Sample records for optical temperature sensor

  1. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, James W. (Aiken, SC)

    1998-01-01T23:59:59.000Z

    An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually using a sensor chip and an accompanying color card.

  2. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1998-06-30T23:59:59.000Z

    An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually using a sensor chip and an accompanying color card. 8 figs.

  3. Dynamic temperature measurements with embedded optical sensors.

    SciTech Connect (OSTI)

    Dolan, Daniel H.,; Seagle, Christopher T; Ao, Tommy

    2013-10-01T23:59:59.000Z

    This report summarizes LDRD project number 151365, %5CDynamic Temperature Measurements with Embedded Optical Sensors%22. The purpose of this project was to develop an optical sensor capable of detecting modest temperature states (<1000 K) with nanosecond time resolution, a recurring diagnostic need in dynamic compression experiments at the Sandia Z machine. Gold sensors were selected because the visible re ectance spectrum of gold varies strongly with temperature. A variety of static and dynamic measurements were performed to assess re ectance changes at di erent temperatures and pressures. Using a minimal optical model for gold, a plausible connection between static calibrations and dynamic measurements was found. With re nements to the model and diagnostic upgrades, embedded gold sensors seem capable of detecting minor (<50 K) temperature changes under dynamic compression.

  4. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1996-01-01T23:59:59.000Z

    An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually or by utilizing an optical fiber and an electrical sensing circuit.

  5. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1996-08-20T23:59:59.000Z

    An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually or by utilizing an optical fiber and an electrical sensing circuit. 7 figs.

  6. Microbend fiber-optic temperature sensor

    DOE Patents [OSTI]

    Weiss, J.D.

    1995-05-30T23:59:59.000Z

    A temperature sensor is made of optical fiber into which quasi-sinusoidal microbends have been permanently introduced. In particular, the present invention includes a graded-index optical fiber directing steady light through a section of the optical fiber containing a plurality of permanent microbends. The microbend section of the optical fiber is contained in a thermally expansive sheath, attached to a thermally expansive structure, or attached to a bimetallic element undergoing temperature changes and being monitored. The microbend section is secured to the thermally expansive sheath which allows the amplitude of the microbends to decrease with temperature. The resultant increase in the optical fiber`s transmission thus allows temperature to be measured. The plural microbend section of the optical fiber is secured to the thermally expansive structure only at its ends and the microbends themselves are completely unconstrained laterally by any bonding agent to obtain maximum longitudinal temperature sensitivity. Although the permanent microbends reduce the transmission capabilities of fiber optics, the present invention utilizes this phenomenon as a transduction mechanism which is optimized to measure temperature. 5 figs.

  7. Microbend fiber-optic temperature sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    1995-01-01T23:59:59.000Z

    A temperature sensor is made of optical fiber into which quasi-sinusoidal microbends have been permanently introduced. In particular, the present invention includes a graded-index optical fiber directing steady light through a section of the optical fiber containing a plurality of permanent microbends. The microbend section of the optical fiber is contained in a thermally expansive sheath, attached to a thermally expansive structure, or attached to a bimetallic element undergoing temperature changes and being monitored. The microbend section is secured to the thermally expansive sheath which allows the amplitude of the microbends to decrease with temperature. The resultant increase in the optical fiber's transmission thus allows temperature to be measured. The plural microbend section of the optical fiber is secured to the thermally expansive structure only at its ends and the microbends themselves are completely unconstrained laterally by any bonding agent to obtain maximum longitudinal temperature sensitivity. Although the permanent microbends reduce the transmission capabilities of fiber optics, the present invention utilizes this phenomenon as a transduction mechanism which is optimized to measure temperature.

  8. Fiber Optic Temperature Sensor for PEM Fuel Cells

    E-Print Network [OSTI]

    Fiber Optic Temperature Sensor for PEM Fuel Cells S.W. Allison, T.J. McIntyre, L.C. Maxey, M a Waveguide Temperature Sensor? · Reliability - fiber optic sensors are immune to oxidizing or reducing Objectives · Develop a low cost, robust temperature sensor for monitoring fuel cell condition and performance

  9. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1994-01-01T23:59:59.000Z

    Optical thermometry is a growing technological field which exploits the ability of certain materials to change their optical properties with temperature. A subclass of such materials are those which change their color as a reversible and reproducible function of temperature. These materials are thermochromic. This invention is a composition to measure temperature utilizing thermochromic semiconductors.

  10. Thin-film fiber optic hydrogen and temperature sensor system

    DOE Patents [OSTI]

    Nave, S.E.

    1998-07-21T23:59:59.000Z

    The invention discloses a sensor probe device for monitoring of hydrogen gas concentrations and temperatures by the same sensor probe. The sensor probe is constructed using thin-film deposition methods for the placement of a multitude of layers of materials sensitive to hydrogen concentrations and temperature on the end of a light transparent lens located within the sensor probe. The end of the lens within the sensor probe contains a lens containing a layer of hydrogen permeable material which excludes other reactive gases, a layer of reflective metal material that forms a metal hydride upon absorbing hydrogen, and a layer of semi-conducting solid that is transparent above a temperature dependent minimum wavelength for temperature detection. The three layers of materials are located at the distal end of the lens located within the sensor probe. The lens focuses light generated by broad-band light generator and connected by fiber-optics to the sensor probe, onto a reflective metal material layer, which passes through the semi-conducting solid layer, onto two optical fibers located at the base of the sensor probe. The reflected light is transmitted over fiber optic cables to a spectrometer and system controller. The absence of electrical signals and electrical wires in the sensor probe provides for an elimination of the potential for spark sources when monitoring in hydrogen rich environments, and provides a sensor free from electrical interferences. 3 figs.

  11. Thin-film fiber optic hydrogen and temperature sensor system

    DOE Patents [OSTI]

    Nave, Stanley E. (Evans, GA)

    1998-01-01T23:59:59.000Z

    The invention discloses a sensor probe device for monitoring of hydrogen gas concentrations and temperatures by the same sensor probe. The sensor probe is constructed using thin-film deposition methods for the placement of a multitude of layers of materials sensitive to hydrogen concentrations and temperature on the end of a light transparent lens located within the sensor probe. The end of the lens within the sensor probe contains a lens containing a layer of hydrogen permeable material which excludes other reactive gases, a layer of reflective metal material that forms a metal hydride upon absorbing hydrogen, and a layer of semi-conducting solid that is transparent above a temperature dependent minimum wavelength for temperature detection. The three layers of materials are located at the distal end of the lens located within the sensor probe. The lens focuses light generated by broad-band light generator and connected by fiber-optics to the sensor probe, onto a reflective metal material layer, which passes through the semi-conducting solid layer, onto two optical fibers located at the base of the sensor probe. The reflected light is transmitted over fiberoptic cables to a spectrometer and system controller. The absence of electrical signals and electrical wires in the sensor probe provides for an elimination of the potential for spark sources when monitoring in hydrogen rich environments, and provides a sensor free from electrical interferences.

  12. Optical Fiber High Temperature Sensor Instrumentation for Energy Intensive Industries

    SciTech Connect (OSTI)

    Cooper, Kristie L.; Wang, Anbo; Pickrell, Gary R.

    2006-11-14T23:59:59.000Z

    This report summarizes technical progress during the program “Optical Fiber High Temperature Sensor Instrumentation for Energy Intensive Industries”, performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. The objective of this program was to use technology recently invented at Virginia Tech to develop and demonstrate the application of self-calibrating optical fiber temperature and pressure sensors to several key energy-intensive industries where conventional, commercially available sensors exhibit greatly abbreviated lifetimes due primarily to environmental degradation. A number of significant technologies were developed under this program, including • a laser bonded silica high temperature fiber sensor with a high temperature capability up to 700°C and a frequency response up to 150 kHz, • the world’s smallest fiber Fabry-Perot high temperature pressure sensor (125 x 20 ?m) with 700°C capability, • UV-induced intrinsic Fabry-Perot interferometric sensors for distributed measurement, • a single crystal sapphire fiber-based sensor with a temperature capability up to 1600°C. These technologies have been well demonstrated and laboratory tested. Our work plan included conducting major field tests of these technologies at EPRI, Corning, Pratt & Whitney, and Global Energy; field validation of the technology is critical to ensuring its usefulness to U.S. industries. Unfortunately, due to budget cuts, DOE was unable to follow through with its funding commitment to support Energy Efficiency Science Initiative projects and this final phase was eliminated.

  13. NEW OPTICAL SENSOR SUITE FOR ULTRAHIGH TEMPERATURE FOSSIL FUEL APPLICATIONS

    SciTech Connect (OSTI)

    Russell G. May; Tony Peng; Tom Flynn

    2004-04-01T23:59:59.000Z

    Accomplishments during the first six months of a program to develop and demonstrate technology for the instrumentation of advanced powerplants are described. Engineers from Prime Research, LC and Babcock and Wilcox Research Center collaborated to generate a list of potential applications for robust photonic sensors in existing and future boiler plants. From that list, three applications were identified as primary candidates for initial development and demonstration of high-temperature sensors in an ultrasupercritical power plant. In addition, progress was made in the development of materials and methods to apply high-temperature optical claddings to sapphire fibers, in order to improve their optical waveguiding properties so that they can be used in the design and fabrication of high-temperature sensors. Through refinements in the processing steps, the quality of the interface between core and cladding of the fibers was improved, which is expected to reduce scattering and attenuation in the fibers.

  14. An investigation of the polarization dependence of a temperature sensor based on an optical microfiber coupler

    E-Print Network [OSTI]

    An investigation of the polarization dependence of a temperature sensor based on an optical is experimentally investigated. The optical microfiber coupler based temperature sensor has a diameter circa 2 m for the development of a range of fiber optic sensors with high sensitivity and microscale dimensions [1

  15. Ultra-High Temperature Sensors Based on Optical Property

    SciTech Connect (OSTI)

    Nabeel Riza

    2008-09-30T23:59:59.000Z

    In this program, Nuonics, Inc. has studied the fundamentals of a new Silicon Carbide (SiC) materials-based optical sensor technology suited for extreme environments of coal-fired engines in power production. The program explored how SiC could be used for sensing temperature, pressure, and potential gas species in a gas turbine environment. The program successfully demonstrated the optical designs, signal processing and experimental data for enabling both temperature and pressure sensing using SiC materials. The program via its sub-contractors also explored gas species sensing using SiC, in this case, no clear commercially deployable method was proven. Extensive temperature and pressure measurement data using the proposed SiC sensors was acquired to 1000 deg-C and 40 atms, respectively. Importantly, a first time packaged all-SiC probe design was successfully operated in a Siemens industrial turbine rig facility with the probe surviving the harsh chemical, pressure, and temperature environment during 28 days of test operations. The probe also survived a 1600 deg-C thermal shock test using an industrial flame.

  16. New Optical Sensor Suite for Ultrahigh Temperature Fossil Fuel Application

    SciTech Connect (OSTI)

    John Coggin; Tom Flynn; Jonas Ivasauskas; Daniel Kominsky; Carrie Kozikowski; Russell May; Michael Miller; Tony Peng; Gary Pickrell; Raymond Rumpf; Kelly Stinson-Bagby; Dan Thorsen; Rena Wilson

    2007-12-31T23:59:59.000Z

    Accomplishments of a program to develop and demonstrate photonic sensor technology for the instrumentation of advanced powerplants and solid oxide fuel cells are described. The goal of this project is the research and development of advanced, robust photonic sensors based on improved sapphire optical waveguides, and the identification and demonstration of applications of the new sensors in advanced fossil fuel power plants, where the new technology will contribute to improvements in process control and monitoring.

  17. Spatially distributed temperatures at the base of two mountain snowpacks measured with fiber-optic sensors

    E-Print Network [OSTI]

    Selker, John

    Spatially distributed temperatures at the base of two mountain snowpacks measured with fiber-optic sensors Scott W. TYLER,1 Susan A. BURAK,2 James P. MCNAMARA,3 Aurele LAMONTAGNE,3 John S. SELKER,4 Jeff, which use the scattered light in a standard telecommunications fiber-optic cable to infer absolute

  18. ULTRA-HIGH TEMPERATURE SENSORS BASED ON OPTICAL PROPERTY MODULATION AND VIBRATION-TOLERANT INTERFEROMETRY

    SciTech Connect (OSTI)

    Nabeel A. Riza

    2005-07-22T23:59:59.000Z

    The goals of the first six months of this project were to begin laying the foundations for both the SiC front-end optical chip fabrication techniques for high pressure gas species sensing as well as the design, assembly, and test of a portable high pressure high temperature calibration test cell chamber for introducing gas species. This calibration cell will be used in the remaining months for proposed first stage high pressure high temperature gas species sensor experimentation and data processing. All these goals have been achieved and are described in detail in the report. Both design process and diagrams for the mechanical elements as well as the optical systems are provided. Photographs of the fabricated calibration test chamber cell, the optical sensor setup with the calibration cell, the SiC sample chip holder, and relevant signal processing mathematics are provided. Initial experimental data from both the optical sensor and fabricated test gas species SiC chips is provided. The design and experimentation results are summarized to give positive conclusions on the proposed novel high temperature high pressure gas species detection optical sensor technology.

  19. Development of Metal Oxide Nanostructure-based Optical Sensors for Fossil Fuel Derived Gases Measurement at High Temperature

    SciTech Connect (OSTI)

    Chen, Kevin

    2014-08-31T23:59:59.000Z

    This final technical report details research works performed supported by a Department of Energy grant (DE-FE0003859), which was awarded under the University Coal Research Program administrated by National Energy Technology Laboratory. This research program studied high temperature fiber sensor for harsh environment applications. It developed two fiber optical sensor platform technology including regenerative fiber Bragg grating sensors and distributed fiber optical sensing based on Rayleigh backscattering optical frequency domain reflectometry. Through the studies of chemical and thermal regenerative techniques for fiber Bragg grating (FBG) fabrication, high-temperature stable FBG sensors were successfully developed and fabricated in air-hole microstructured fibers, high-attenuation fibers, rare-earth doped fibers, and standard telecommunication fibers. By optimizing the laser processing and thermal annealing procedures, fiber grating sensors with stable performance up to 1100oC have been developed. Using these temperature-stable FBG gratings as sensor platform, fiber optical flow, temperature, pressure, and chemical sensors have been developed to operate at high temperatures up to 800oC. Through the integration of on-fiber functional coating, the use of application-specific air-hole microstructural fiber, and application of active fiber sensing scheme, distributed fiber sensor for temperature, pressure, flow, liquid level, and chemical sensing have been demonstrated with high spatial resolution (1-cm or better) with wide temperature ranges. These include the demonstration of 1) liquid level sensing from 77K to the room temperature, pressure/temperature sensing from the room temperature to 800C and from the 15psi to 2000 psi, and hydrogen concentration measurement from 0.2% to 10% with temperature ranges from the room temperature to 700C. Optical sensors developed by this program has broken several technical records including flow sensors with the highest operation temperature up to 750oC, first distributed chemical measurements at the record high temperature up to 700oC, first distributed pressure measurement at the record high temperature up to 800oC, and the fiber laser sensors with the record high operation temperature up to 700oC. The research performed by this program dramatically expand the functionality, adaptability, and applicability of distributed fiber optical sensors with potential applications in a number of high-temperature energy systems such as fossil-fuel power generation, high-temperature fuel cell applications, and potential for nuclear energy systems.

  20. Optical Temperature Sensor Using Infrared-to-Visible-Frequency Upconversion in Er This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Cao, Wenwu

    Optical Temperature Sensor Using Infrared-to-Visible-Frequency Upconversion in Er 3+ /Yb 3. 8 (2011) 087804 Optical Temperature Sensor Using Infrared-to-Visible-Frequency Upconversion in Er3 State University, University Park, Pennsylvania 16802, USA (Received 24 May 2011) An optical temperature

  1. Novel Modified Optical Fibers for High Temperature In-Situ Miniaturized Gas Sensors in Advanced Fossil Energy Systems

    SciTech Connect (OSTI)

    Pickrell, Gary; Scott, Brian

    2014-06-30T23:59:59.000Z

    This report covers the technical progress on the program “Novel Modified Optical Fibers for High Temperature In-Situ Miniaturized Gas Sensors in Advanced Fossil Energy Systems”, funded by the National Energy Technology Laboratory of the U.S. Department of Energy, and performed by the Materials Science & Engineering and Electrical & Computer Engineering Departments at Virginia Tech, and summarizes technical progress from July 1st, 2005 –June 30th, 2014. The objective of this program was to develop novel fiber materials for high temperature gas sensors based on evanescent wave absorption in optical fibers. This project focused on two primary areas: the study of a sapphire photonic crystal fiber (SPCF) for operation at high temperature and long wavelengths, and a porous glass based fiber optic sensor for gas detection. The sapphire component of the project focused on the development of a sapphire photonic crystal fiber, modeling of the new structures, fabrication of the optimal structure, development of a long wavelength interrogation system, testing of the optical properties, and gas and temperature testing of the final sensor. The fabrication of the 6 rod SPCF gap bundle (diameter of 70?m) with a hollow core was successfully constructed with lead-in and lead-out 50?m diameter fiber along with transmission and gas detection testing. Testing of the sapphire photonic crystal fiber sensor capabilities with the developed long wavelength optical system showed the ability to detect CO2 at or below 1000ppm at temperatures up to 1000°C. Work on the porous glass sensor focused on the development of a porous clad solid core optical fiber, a hollow core waveguide, gas detection capabilities at room and high temperature, simultaneous gas species detection, suitable joining technologies for the lead-in and lead-out fibers and the porous sensor, sensor system sensitivity improvement, signal processing improvement, relationship between pore structure and fiber geometry to optical properties, and the development of a sensor packaging prototype for laboratory testing. Analysis and experiments determined that a bonding technique using a CO2 laser is the most suitable joining technique. Pore morphology alteration showed that transmission improved with increasing annealing temperature (producing smaller pores), while the sensor response time increased and the mechanical strength decreased with increasing annealing temperature. Software was developed for data acquisition and signal processing to collect and interpret spectral gas absorption data. Gas detection on porous glass sensors was completed and the detection limit was evaluated using acetylene and was found to be around 1- 200ppm. A complete materials package for porous glass sensors was manufactured for testing.

  2. Analysis of a distributed fiber-optic temperature sensor using single-photon detectors

    E-Print Network [OSTI]

    Shellee D. Dyer; Michael G. Tanner; Burm Baek; Robert H. Hadfield; Sae Woo Nam

    2011-11-17T23:59:59.000Z

    We demonstrate a high-accuracy distributed fiber-optic temperature sensor using superconducting nanowire single-photon detectors and single-photon counting techniques. Our demonstration uses inexpensive single-mode fiber at standard telecommunications wavelengths as the sensing fiber, which enables extremely low-loss experiments and compatibility with existing fiber networks. We show that the uncertainty of the temperature measurement decreases with longer integration periods, but is ultimately limited by the calibration uncertainty. Temperature uncertainty on the order of 3 K is possible with spatial resolution of the order of 1 cm and integration period as small as 60 seconds. Also, we show that the measurement is subject to systematic uncertainties, such as polarization fading, which can be reduced with a polarization diversity receiver.

  3. Fluorescent temperature sensor

    DOE Patents [OSTI]

    Baker, Gary A [Los Alamos, NM; Baker, Sheila N [Los Alamos, NM; McCleskey, T Mark [Los Alamos, NM

    2009-03-03T23:59:59.000Z

    The present invention is a fluorescent temperature sensor or optical thermometer. The sensor includes a solution of 1,3-bis(1-pyrenyl)propane within a 1-butyl-1-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid solvent. The 1,3-bis(1-pyrenyl)propane remains unassociated when in the ground state while in solution. When subjected to UV light, an excited state is produced that exists in equilibrium with an excimer. The position of the equilibrium between the two excited states is temperature dependent.

  4. Extreme temperature robust optical sensor designs and fault-tolerant signal processing

    DOE Patents [OSTI]

    Riza, Nabeel Agha (Oviedo, FL); Perez, Frank (Tujunga, CA)

    2012-01-17T23:59:59.000Z

    Silicon Carbide (SiC) probe designs for extreme temperature and pressure sensing uses a single crystal SiC optical chip encased in a sintered SiC material probe. The SiC chip may be protected for high temperature only use or exposed for both temperature and pressure sensing. Hybrid signal processing techniques allow fault-tolerant extreme temperature sensing. Wavelength peak-to-peak (or null-to-null) collective spectrum spread measurement to detect wavelength peak/null shift measurement forms a coarse-fine temperature measurement using broadband spectrum monitoring. The SiC probe frontend acts as a stable emissivity Black-body radiator and monitoring the shift in radiation spectrum enables a pyrometer. This application combines all-SiC pyrometry with thick SiC etalon laser interferometry within a free-spectral range to form a coarse-fine temperature measurement sensor. RF notch filtering techniques improve the sensitivity of the temperature measurement where fine spectral shift or spectrum measurements are needed to deduce temperature.

  5. Fiber optic sensor and method for making

    DOE Patents [OSTI]

    Vartuli, James Scott; Bousman, Kenneth Sherwood; Deng, Kung-Li; McEvoy, Kevin Paul; Xia, Hua

    2010-05-18T23:59:59.000Z

    A fiber optic sensor including a fiber having a modified surface integral with the fiber wherein the modified surface includes an open pore network with optical agents dispersed within the open pores of the open pore network. Methods for preparing the fiber optic sensor are also provided. The fiber optic sensors can withstand high temperatures and harsh environments.

  6. Fiber optic temperature sensor using a grating on an angled fiber tip 

    E-Print Network [OSTI]

    Varadarajan, Harini

    2000-01-01T23:59:59.000Z

    up to observe the response of the sensor to changes in temperature in a furnace was built and the test results are in general agreement with prediction. The reflected power is observed to vary approximately as a sinusoidal function as expected...

  7. Fiber optic coupled optical sensor

    DOE Patents [OSTI]

    Fleming, Kevin J. (Albuquerque, NM)

    2001-01-01T23:59:59.000Z

    A displacement sensor includes a first optical fiber for radiating light to a target, and a second optical fiber for receiving light from the target. The end of the first fiber is adjacent and not axially aligned with the second fiber end. A lens focuses light from the first fiber onto the target and light from the target onto the second fiber.

  8. Fiber optic vibration sensor

    DOE Patents [OSTI]

    Dooley, Joseph B. (Harriman, TN); Muhs, Jeffrey D. (Lenoir City, TN); Tobin, Kenneth W. (Harriman, TN)

    1995-01-01T23:59:59.000Z

    A fiber optic vibration sensor utilizes two single mode optical fibers supported by a housing with one optical fiber fixedly secured to the housing and providing a reference signal and the other optical fiber having a free span length subject to vibrational displacement thereof with respect to the housing and the first optical fiber for providing a signal indicative of a measurement of any perturbation of the sensor. Damping or tailoring of the sensor to be responsive to selected levels of perturbation is provided by altering the diameter of optical fibers or by immersing at least a portion of the free span length of the vibration sensing optical fiber into a liquid of a selected viscosity.

  9. Fiber optic vibration sensor

    DOE Patents [OSTI]

    Dooley, J.B.; Muhs, J.D.; Tobin, K.W.

    1995-01-10T23:59:59.000Z

    A fiber optic vibration sensor utilizes two single mode optical fibers supported by a housing with one optical fiber fixedly secured to the housing and providing a reference signal and the other optical fiber having a free span length subject to vibrational displacement thereof with respect to the housing and the first optical fiber for providing a signal indicative of a measurement of any perturbation of the sensor. Damping or tailoring of the sensor to be responsive to selected levels of perturbation is provided by altering the diameter of optical fibers or by immersing at least a portion of the free span length of the vibration sensing optical fiber into a liquid of a selected viscosity. 2 figures.

  10. Fiber optic geophysical sensors

    DOE Patents [OSTI]

    Homuth, E.F.

    1991-03-19T23:59:59.000Z

    A fiber optic geophysical sensor is described in which laser light is passed through a sensor interferometer in contact with a geophysical event, and a reference interferometer not in contact with the geophysical event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects. 2 figures.

  11. Optical displacement sensor

    DOE Patents [OSTI]

    Carr, Dustin W. (Albuquerque, NM)

    2008-04-08T23:59:59.000Z

    An optical displacement sensor is disclosed which uses a vertical-cavity surface-emitting laser (VCSEL) coupled to an optical cavity formed by a moveable membrane and an output mirror of the VCSEL. This arrangement renders the lasing characteristics of the VCSEL sensitive to any movement of the membrane produced by sound, vibrations, pressure changes, acceleration, etc. Some embodiments of the optical displacement sensor can further include a light-reflective diffractive lens located on the membrane or adjacent to the VCSEL to control the amount of lasing light coupled back into the VCSEL. A photodetector detects a portion of the lasing light from the VCSEL to provide an electrical output signal for the optical displacement sensor which varies with the movement of the membrane.

  12. Optical and mechanical behavior of the optical fiber infrasound sensor

    E-Print Network [OSTI]

    DeWolf, Scott

    2009-01-01T23:59:59.000Z

    1.2 The Optical Fiber Infrasound Sensor . . . . . . .Fiber Infrasound Sensor Optical fibers are well known forSchnidrig. An optical fiber infrasound sensor: A new lower

  13. Optical Fiber Chemical Sensor with Sol-Gel Derived Refractive Material as Transducer for High Temperature Gas Sensing in Clean Coal Technology

    SciTech Connect (OSTI)

    Shiquan Tao

    2006-12-31T23:59:59.000Z

    The chemistry of sol-gel derived silica and refractive metal oxide has been systematically studied. Sol-gel processes have been developed for preparing porous silica and semiconductor metal oxide materials. Micelle/reversed micelle techniques have been developed for preparing nanometer sized semiconductor metal oxides and noble metal particles. Techniques for doping metal ions, metal oxides and nanosized metal particles into porous sol-gel material have also been developed. Optical properties of sol-gel derived materials in ambient and high temperature gases have been studied by using fiber optic spectroscopic techniques, such as fiber optic ultraviolet/visible absorption spectrometry, fiber optic near infrared absorption spectrometry and fiber optic fluorescence spectrometry. Fiber optic spectrometric techniques have been developed for investigating the optical properties of these sol-gel derived materials prepared as porous optical fibers or as coatings on the surface of silica optical fibers. Optical and electron microscopic techniques have been used to observe the microstructure, such as pore size, pore shape, sensing agent distribution, of sol-gel derived material, as well as the size and morphology of nanometer metal particle doped in sol-gel derived porous silica, the nature of coating of sol-gel derived materials on silica optical fiber surface. In addition, the chemical reactions of metal ion, nanostructured semiconductor metal oxides and nanometer sized metal particles with gas components at room temperature and high temperatures have also been investigated with fiber optic spectrometric methods. Three classes of fiber optic sensors have been developed based on the thorough investigation of sol-gel chemistry and sol-gel derived materials. The first group of fiber optic sensors uses porous silica optical fibers doped with metal ions or metal oxide as transducers for sensing trace NH{sub 3} and H{sub 2}S in high temperature gas samples. The second group of fiber optic sensors uses sol-gel derived porous silica materials doped with nanometer particles of noble metals in the form of fiber or coating for sensing trace H{sub 2}, NH{sub 3} and HCl in gas samples at for applications ambient temperature. The third classes of fiber optic sensors use sol-gel derived semiconductor metal oxide coating on the surface of silica optical fiber as transducers for selectively sensing H{sub 2}, CH{sub 4} and CO at high temperature. In addition, optical fiber temperature sensors use the fluorescence signal of rare-earth metal ions doped porous silica optical fiber or the optical absorption signal of thermochromic metal oxide materials coated on the surface of silica optical fibers have also been developed for monitoring gas temperature of corrosive gas. Based on the results obtained from this project, the principle of fiber optic sensor techniques for monitoring matrix gas components as well as trace components of coal gasification derived syngas has been established. Prototype sensors for sensing trace ammonia and hydrogen sulfide in gasification derived syngas have been built up in our laboratory and have been tested using gas samples with matrix gas composition similar to that of gasification derived fuel gas. Test results illustrated the feasibility of these sensors for applications in IGCC processes.

  14. Integrated optical sensor

    DOE Patents [OSTI]

    Watkins, A.D.; Smartt, H.B.; Taylor, P.L.

    1994-01-04T23:59:59.000Z

    An integrated optical sensor for arc welding having multifunction feedback control is described. The sensor, comprising generally a CCD camera and diode laser, is positioned behind the arc torch for measuring weld pool position and width, standoff distance, and post-weld centerline cooling rate. Computer process information from this sensor is passed to a controlling computer for use in feedback control loops to aid in the control of the welding process. Weld pool position and width are used in a feedback loop, by the weld controller, to track the weld pool relative to the weld joint. Sensor standoff distance is used in a feedback loop to control the contact tip to base metal distance during the welding process. Cooling rate information is used to determine the final metallurgical state of the weld bead and heat affected zone, thereby controlling post-weld mechanical properties. 6 figures.

  15. Integrated optical sensor

    DOE Patents [OSTI]

    Watkins, Arthur D. (Idaho Falls, ID); Smartt, Herschel B. (Idaho Falls, ID); Taylor, Paul L. (Idaho Falls, ID)

    1994-01-01T23:59:59.000Z

    An integrated optical sensor for arc welding having multifunction feedback control. The sensor, comprising generally a CCD camera and diode laser, is positioned behind the arc torch for measuring weld pool position and width, standoff distance, and post-weld centerline cooling rate. Computer process information from this sensor is passed to a controlling computer for use in feedback control loops to aid in the control of the welding process. Weld pool position and width are used in a feedback loop, by the weld controller, to track the weld pool relative to the weld joint. Sensor standoff distance is used in a feedback loop to control the contact tip to base metal distance during the welding process. Cooling rate information is used to determine the final metallurgical state of the weld bead and heat affected zone, thereby controlling post-weld mechanical properties.

  16. Fiber optic hydrogen sensor

    DOE Patents [OSTI]

    Buchanan, B.R.; Prather, W.S.

    1991-01-01T23:59:59.000Z

    Apparatus and method for detecting a chemical substance by exposing an optic fiber having a core and a cladding to the chemical substance so that the chemical substance can be adsorbed onto the surface of the cladding. The optic fiber is coiled inside a container having a pair of valves for controlling the entrance and exit of the substance. Light from a light source is received by one end of the optic fiber, preferably external to the container, and carried by the core of the fiber. Adsorbed substance changes the transmissivity of the fiber as measured by a spectrophotometer at the other end, also preferably external to the container. Hydrogen is detected by the absorption of infrared light carried by an optic fiber with a silica cladding. Since the adsorption is reversible, a sensor according to the present invention can be used repeatedly. Multiple positions in a process system can be monitored using a single container that can be connected to each location to be monitored so that a sample can be obtained for measurement, or, alternatively, containers can be placed near each position and the optic fibers carrying the partially-absorbed light can be multiplexed for rapid sequential reading, by a single spectrophotometer.

  17. Optical humidity sensor

    DOE Patents [OSTI]

    Tarvin, J.A.

    1987-02-10T23:59:59.000Z

    An optical dielectric humidity sensor is disclosed which includes a dielectric mirror having multiple alternating layers of two porous water-adsorbent dielectric materials with differing indices of refraction carried by a translucent substrate. A narrow-band polarized light source is positioned to direct light energy onto the mirror, and detectors are positioned to receive light energy transmitted through and reflected by the mirror. A ratiometer indicates humidity in the atmosphere which surrounds the dielectric mirror as a function of a ratio of light energies incident on the detectors. 2 figs.

  18. Fluorescent optical position sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D.

    2005-11-15T23:59:59.000Z

    A fluorescent optical position sensor and method of operation. A small excitation source side-pumps a localized region of fluorescence at an unknown position along a fluorescent waveguide. As the fluorescent light travels down the waveguide, the intensity of fluorescent light decreases due to absorption. By measuring with one (or two) photodetectors the attenuated intensity of fluorescent light emitted from one (or both) ends of the waveguide, the position of the excitation source relative to the waveguide can be determined by comparing the measured light intensity to a calibrated response curve or mathematical model. Alternatively, excitation light can be pumped into an end of the waveguide, which generates an exponentially-decaying continuous source of fluorescent light along the length of the waveguide. The position of a photodetector oriented to view the side of the waveguide can be uniquely determined by measuring the intensity of the fluorescent light emitted radially at that location.

  19. TRS-Fiber Optic Classifier Sensor Installation

    E-Print Network [OSTI]

    Prevedouros, Panos D.

    TRS-Fiber Optic Classifier Sensor Installation The sensor that the Traffic Recording System (TRS) uses is the Flexsense Portable Fiberoptic Sensor System by Optical Sensor Systems. This includes two is undetected by the TRS. The user must make sure that the sensors do not get bent or twisted or the fiber optic

  20. Buried fiber optic intrusion sensor 

    E-Print Network [OSTI]

    Maier, Eric William

    2004-09-30T23:59:59.000Z

    A distributed fiber optic intrusion sensor capable of detecting intruders from the pressure of their weight on the earth's surface was investigated in the laboratory and in field tests. The presence of an intruder above or in proximity...

  1. Low noise optical position sensor

    DOE Patents [OSTI]

    Spear, J.D.

    1999-03-09T23:59:59.000Z

    A novel optical position sensor is described that uses two component photodiodes electrically connected in parallel, with opposing polarities. A lens provides optical gain and restricts the acceptance angle of the detector. The response of the device to displacements of an optical spot is similar to that of a conventional bi-cell type position sensitive detector. However, the component photodiode design enables simpler electronic amplification with inherently less electrical noise than the bi-cell. Measurements by the sensor of the pointing noise of a focused helium-neon laser as a function of frequency demonstrate high sensitivity and suitability for optical probe beam deflection experiments. 14 figs.

  2. Low noise optical position sensor

    DOE Patents [OSTI]

    Spear, Jonathan David (Berkeley, CA)

    1999-01-01T23:59:59.000Z

    A novel optical position sensor is described that uses two component photodiodes electrically connected in parallel, with opposing polarities. A lens provides optical gain and restricts the acceptance angle of the detector. The response of the device to displacements of an optical spot is similar to that of a conventional bi-cell type position sensitive detector. However, the component photodiode design enables simpler electronic amplification with inherently less electrical noise than the bi-cell. Measurements by the sensor of the pointing noise of a focused helium-neon laser as a function of frequency demonstrate high sensitivity and suitability for optical probe beam deflection experiments.

  3. High temperature, minimally invasive optical sensing modules

    DOE Patents [OSTI]

    Riza, Nabeel Agha (Oviedo, FL); Perez, Frank (Tujunga, CA)

    2008-02-05T23:59:59.000Z

    A remote temperature sensing system includes a light source selectively producing light at two different wavelengths and a sensor device having an optical path length that varies as a function of temperature. The sensor receives light emitted by the light source and redirects the light along the optical path length. The system also includes a detector receiving redirected light from the sensor device and generating respective signals indicative of respective intensities of received redirected light corresponding to respective wavelengths of light emitted by the light source. The system also includes a processor processing the signals generated by the detector to calculate a temperature of the device.

  4. Method and apparatus for optical temperature measurement

    DOE Patents [OSTI]

    O'Rourke, P.E.; Livingston, R.R.; Prather, W.S.

    1994-09-20T23:59:59.000Z

    A temperature probe and a method for using said probe for temperature measurements based on changes in light absorption by the probe are disclosed. The probe comprises a first and a second optical fiber that carry light to and from the probe, and a temperature sensor material, the absorbance of which changes with temperature, through which the light is directed. Light is directed through the first optical fiber, passes through the temperature sensor material, and is transmitted by a second optical fiber from the material to a detector. Temperature-dependent and temperature-independent factors are derived from measurements of the transmitted light intensity. For each sensor material, the temperature T is a function of the ratio, R, of these factors. The temperature function f(R) is found by applying standard data analysis techniques to plots of T versus R at a series of known temperatures. For a sensor having a known temperature function f(R) and known characteristic and temperature-dependent factors, the temperature can be computed from a measurement of R. Suitable sensor materials include neodymium-doped borosilicate glass, accurate to [+-]0.5 C over an operating temperature range of about [minus]196 C to 400 C; and a mixture of D[sub 2]O and H[sub 2]O, accurate to [+-]0.1 C over an operating range of about 5 C to 90 C. 13 figs.

  5. Method and apparatus for optical temperature measurement

    DOE Patents [OSTI]

    O'Rourke, Patrick E. (Martinez, GA); Livingston, Ronald R. (Aiken, SC); Prather, William S. (Augusta, GA)

    1994-01-01T23:59:59.000Z

    A temperature probe and a method for using said probe for temperature measurements based on changes in light absorption by the probe. The probe comprises a first and a second optical fiber that carry light to and from the probe, and a temperature sensor material, the absorbance of which changes with temperature, through which the light is directed. Light is directed through the first optical fiber, passes through the temperature sensor material, and is transmitted by a second optical fiber from the material to a detector. Temperature-dependent and temperature-independent factors are derived from measurements of the transmitted light intensity. For each sensor material, the temperature T is a function of the ratio, R, of these factors. The temperature function f(R) is found by applying standard data analysis techniques to plots of T versus R at a series of known temperatures. For a sensor having a known temperature function f(R) and known characteristic and temperature-dependent factors, the temperature can be computed from a measurement of R. Suitable sensor materials include neodymium-doped boresilicate glass, accurate to .+-.0.5.degree. C. over an operating temperature range of about -196.degree. C. to 400.degree. C.; and a mixture of D.sub.2 O and H.sub.2 O, accurate to .+-.0.1.degree. C. over an operating range of about 5.degree. C. to 90.degree. C.

  6. Battery system with temperature sensors

    DOE Patents [OSTI]

    Wood, Steven J.; Trester, Dale B.

    2012-11-13T23:59:59.000Z

    A battery system to monitor temperature includes at least one cell with a temperature sensing device proximate the at least one cell. The battery system also includes a flexible member that holds the temperature sensor proximate to the at least one cell.

  7. Dual neutron flux/temperature measurement sensor

    DOE Patents [OSTI]

    Mihalczo, J.T.; Simpson, M.L.; McElhaney, S.A.

    1994-10-04T23:59:59.000Z

    Simultaneous measurement of neutron flux and temperature is provided by a single sensor which includes a phosphor mixture having two principal constituents. The first constituent is a neutron sensitive 6LiF and the second is a rare-earth activated Y203 thermophosphor. The mixture is coated on the end of a fiber optic, while the opposite end of the fiber optic is coupled to a light detector. The detected light scintillations are quantified for neutron flux determination, and the decay is measured for temperature determination. 3 figs.

  8. NSTX High Temperature Sensor Systems

    SciTech Connect (OSTI)

    B.McCormack; H.W. Kugel; P. Goranson; R. Kaita; et al

    1999-11-01T23:59:59.000Z

    The design of the more than 300 in-vessel sensor systems for the National Spherical Torus Experiment (NSTX) has encountered several challenging fusion reactor diagnostic issues involving high temperatures and space constraints. This has resulted in unique miniature, high temperature in-vessel sensor systems mounted in small spaces behind plasma facing armor tiles, and they are prototypical of possible high power reactor first-wall applications. In the Center Stack, Divertor, Passive Plate, and vessel wall regions, the small magnetic sensors, large magnetic sensors, flux loops, Rogowski Coils, thermocouples, and Langmuir Probes are qualified for 600 degrees C operation. This rating will accommodate both peak rear-face graphite tile temperatures during operations and the 350 degrees C bake-out conditions. Similar sensor systems including flux loops, on other vacuum vessel regions are qualified for 350 degrees C operation. Cabling from the sensors embedded in the graphite tiles follows narrow routes to exit the vessel. The detailed sensor design and installation methods of these diagnostic systems developed for high-powered ST operation are discussed.

  9. Battery system with temperature sensors

    DOE Patents [OSTI]

    Wood, Steven J; Trester, Dale B

    2014-02-04T23:59:59.000Z

    A battery system includes a platform having an aperture formed therethrough, a flexible member having a generally planar configuration and extending across the aperture, wherein a portion of the flexible member is coextensive with the aperture, a cell provided adjacent the platform, and a sensor coupled to the flexible member and positioned proximate the cell. The sensor is configured to detect a temperature of the cell.

  10. High pressure fiber optic sensor system

    SciTech Connect (OSTI)

    Guida, Renato; Xia, Hua; Lee, Boon K; Dekate, Sachin N

    2013-11-26T23:59:59.000Z

    The present application provides a fiber optic sensor system. The fiber optic sensor system may include a small diameter bellows, a large diameter bellows, and a fiber optic pressure sensor attached to the small diameter bellows. Contraction of the large diameter bellows under an applied pressure may cause the small diameter bellows to expand such that the fiber optic pressure sensor may measure the applied pressure.

  11. Silicon fiber optic sensors

    DOE Patents [OSTI]

    Pocha, Michael D. (Livermore, CA); Swierkowski, Steve P. (Livermore, CA); Wood, Billy E. (Livermore, CA)

    2007-10-02T23:59:59.000Z

    A Fabry-Perot cavity is formed by a partially or wholly reflective surface on the free end of an integrated elongate channel or an integrated bounding wall of a chip of a wafer and a partially reflective surface on the end of the optical fiber. Such a constructed device can be utilized to detect one or more physical parameters, such as, for example, strain, through the optical fiber using an optical detection system to provide measuring accuracies of less than aboutb0.1%.

  12. Buried fiber optic intrusion sensor

    E-Print Network [OSTI]

    Maier, Eric William

    2004-09-30T23:59:59.000Z

    to the buried sensor induces a phase shift in light propagating along the fiber which allows for the detection and localization of intrusions. Through the use of an ultra-stable erbium-doped fiber laser and phase sensitive optical time domain reflectometry...

  13. Optic Flow Sensor Objective: Using optic flow sensors, detect and track

    E-Print Network [OSTI]

    Wirthlin, Michael J.

    Optic Flow Sensor Objective: Using optic flow sensors, detect and track the walls of a rural or urban terrain. Principle Investigators: Tim McLain, Randy Beard Optic Flow Sensor · Computationally factor ­ 1" x 1" x 1.5" · Inexpensive ­ $80 including optics · Fast ­ computes optic flow at 2300 fps2006

  14. Optical high acidity sensor

    DOE Patents [OSTI]

    Jorgensen, B.S.; Nekimken, H.L.; Carey, W.P.; O`Rourke, P.E.

    1997-07-22T23:59:59.000Z

    An apparatus and method for determining acid concentrations in solutions having acid concentrations of from about 0.1 Molar to about 16 Molar is disclosed. The apparatus includes a chamber for interrogation of the sample solution, a fiber optic light source for passing light transversely through the chamber, a fiber optic collector for receiving the collimated light after transmission through the chamber, a coating of an acid resistant polymeric composition upon at least one fiber end or lens, the polymeric composition in contact with the sample solution within the chamber and having a detectable response to acid concentrations within the range of from about 0.1 Molar to about 16 Molar, a measurer for the response of the polymeric composition in contact with the sample solution, and a comparer of the measured response to predetermined standards whereby the acid molarity of the sample solution within the chamber can be determined. Preferably, a first lens is attached to the end of the fiber optic light source, the first lens adapted to collimate light from the fiber optic light source, and a second lens is attached to the end of the fiber optic collector for focusing the collimated light after transmission through the chamber. 10 figs.

  15. Drexel University Temperature Sensors

    SciTech Connect (OSTI)

    K. L. Davis; D. L. Knudson; J. L. Rempe; B. M. Chase

    2014-09-01T23:59:59.000Z

    This document summarizes background information and presents results related to temperature measurements in the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) Drexel University Project 31091 irradiation. The objective of this test was to assess the radiation performance of new ceramic materials for advanced reactor applications. Accordingly, irradiations of transition metal carbides and nitrides were performed using the Hydraulic Shuttle Irradiation System (HSIS) in the B-7 position and in static capsules inserted into the A-3 and East Flux Trap Position 5 locations of the ATR.

  16. Fiber optic moisture sensor

    DOE Patents [OSTI]

    Kirkham, R.R.

    1984-08-03T23:59:59.000Z

    A method and apparatus for sensing moisture changes by utilizing optical fiber technology. One embodiment uses a reflective target at the end of an optical fiber. The reflectance of the target varies with its moisture content and can be detected by a remote unit at the opposite end of the fiber. A second embodiment utilizes changes in light loss along the fiber length. This can be attributed to changes in reflectance of cladding material as a function of its moisture content. It can also be affected by holes or inserts interposed in the cladding material and/or fiber. Changing light levels can also be coupled from one fiber to another in an assembly of fibers as a function of varying moisture content in their overlapping lengths of cladding material.

  17. Double-pulse Brillouin distributed optical fiber sensors: analytical model and experimental validation

    E-Print Network [OSTI]

    Thévenaz, Jacques

    Double-pulse Brillouin distributed optical fiber sensors: analytical model and experimental-pulse Brillouin optical time-domain analysis (DP-BOTDA) sensors. The proposed model is a tool that provides a full. Keywords: Stimulated Brillouin scattering, distributed optical fiber sensor, temperature sensing, strain

  18. Abstract--A low noise optical sensor and biocompatible microscale optical filters for integrated fluorescence sensors

    E-Print Network [OSTI]

    Maryland at College Park, University of

    Abstract--A low noise optical sensor and biocompatible microscale optical filters for integrated sensors. The transmission ratio in the pass-band and suppression ratio in the stop-band of the optical and of the optical filter. Test results comparing sensor and filter performance with competing technologies

  19. Semiconductor sensor for optically measuring polarization rotation of optical wavefronts using rare earth iron garnets

    DOE Patents [OSTI]

    Duncan, Paul G. (8544 Electric Ave., Vienna, VA 22182)

    2002-01-01T23:59:59.000Z

    Described are the design of a rare earth iron garnet sensor element, optical methods of interrogating the sensor element, methods of coupling the optical sensor element to a waveguide, and an optical and electrical processing system for monitoring the polarization rotation of a linearly polarized wavefront undergoing external modulation due to magnetic field or electrical current fluctuation. The sensor element uses the Faraday effect, an intrinsic property of certain rare-earth iron garnet materials, to rotate the polarization state of light in the presence of a magnetic field. The sensor element may be coated with a thin-film mirror to effectively double the optical path length, providing twice the sensitivity for a given field strength or temperature change. A semiconductor sensor system using a rare earth iron garnet sensor element is described.

  20. OPTICAL FIBER SENSOR TECHNOLOGIES FOR EFFICIENT AND ECONOMICAL OIL RECOVERY

    SciTech Connect (OSTI)

    Kristie Cooper; Gary Pickrell; Anbo Wang

    2003-04-01T23:59:59.000Z

    This report summarizes technical progress over the fourth year of the ''Optical Fiber Sensor Technologies for Efficient and Economical Oil Recovery'' program, funded by the Federal Energy Technology Center of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. During the reporting period, research efforts under the program were focused on the development and evaluation of the fiber optic flow sensor system, and field testing in Tulsa, OK and the second field test of the pressure and temperature sensors in Coalinga, CA. The feasibility of a self-compensating fiber optic flow sensor based on a cantilever beam and interferometer for real-time flow rate measurements in the fluid filled pipes of oil field was clearly demonstrated. In addition, field testing of the pressure and temperature sensors deployed downhole continued. These accomplishments are summarized here: (1) Theoretical analysis and simulations were performed to ensure performance of the design. (2) The sensor fabrication and packaging techniques were investigated and improved. (3) Prototype flow sensors were fabricated based on the fabrication experience of hundreds of test sensors. (4) A lab-scale flow testing system was constructed and used for sensor evaluation. (5) Field-testing was performed in both the indoor and outdoor flow testing facility at the University of Tulsa, OK. (6) Testing of a multimode white light pressure and temperature sensor system continued at the oil site of Chevron/Texaco Company (Coalinga CA).

  1. Design guidelines for optical resonator biochemical sensors

    E-Print Network [OSTI]

    Kimerling, Lionel C.

    In this paper, we propose a design tool for dielectric optical resonator-based biochemical refractometry sensors. Analogous to the widely accepted photodetector figure of merit, the detectivity D*, we introduce a new sensor ...

  2. Integrated optical tamper sensor with planar waveguide

    DOE Patents [OSTI]

    Carson, R.F.; Casalnuovo, S.A.

    1993-01-05T23:59:59.000Z

    A monolithic optical tamper sensor, comprising an optical emitter and detector, connected by an optical waveguide and placed into the critical entry plane of an enclosed sensitive region, the tamper sensor having a myriad of scraps of a material optically absorbent at the wavelength of interest, such that when the absorbent material is in place on the waveguide, an unique optical signature can be recorded, but when entry is attempted into the enclosed sensitive region, the scraps of absorbent material will be displaced and the optical/electrical signature of the tamper sensor will change and that change can be recorded.

  3. Integrated optical tamper sensor with planar waveguide

    DOE Patents [OSTI]

    Carson, Richard F. (Albuquerque, NM); Casalnuovo, Stephen A. (Albuquerque, NM)

    1993-01-01T23:59:59.000Z

    A monolithic optical tamper sensor, comprising an optical emitter and detector, connected by an optical waveguide and placed into the critical entry plane of an enclosed sensitive region, the tamper sensor having a myriad of scraps of a material optically absorbent at the wavelength of interest, such that when the absorbent material is in place on the waveguide, an unique optical signature can be recorded, but when entry is attempted into the enclosed sensitive region, the scraps of absorbent material will be displaced and the optical/electrical signature of the tamper sensor will change and that change can be recorded.

  4. Sandia National Laboratories: Sensors & Optical Diagnostics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Optimizing Engines for Alternative Fuels On September 10, 2013, in CRF, Energy, Facilities, News, News & Events, Research & Capabilities, Sensors & Optical Diagnostics,...

  5. Optical sensor of magnetic fields

    DOE Patents [OSTI]

    Butler, M.A.; Martin, S.J.

    1986-03-25T23:59:59.000Z

    An optical magnetic field strength sensor for measuring the field strength of a magnetic field comprising a dilute magnetic semi-conductor probe having first and second ends, longitudinally positioned in the magnetic field for providing Faraday polarization rotation of light passing therethrough relative to the strength of the magnetic field. Light provided by a remote light source is propagated through an optical fiber coupler and a single optical fiber strand between the probe and the light source for providing a light path therebetween. A polarizer and an apparatus for rotating the polarization of the light is provided in the light path and a reflector is carried by the second end of the probe for reflecting the light back through the probe and thence through the polarizer to the optical coupler. A photo detector apparatus is operably connected to the optical coupler for detecting and measuring the intensity of the reflected light and comparing same to the light source intensity whereby the magnetic field strength may be calculated.

  6. Carbon nanotube temperature and pressure sensors

    DOE Patents [OSTI]

    Ivanov, Ilia N; Geohegan, David Bruce

    2013-10-29T23:59:59.000Z

    The present invention, in one embodiment, provides a method of measuring pressure or temperature using a sensor including a sensor element composed of a plurality of carbon nanotubes. In one example, the resistance of the plurality of carbon nanotubes is measured in response to the application of temperature or pressure. The changes in resistance are then recorded and correlated to temperature or pressure. In one embodiment, the present invention provides for independent measurement of pressure or temperature using the sensors disclosed herein.

  7. Electro-optic high voltage sensor

    DOE Patents [OSTI]

    Davidson, James R.; Seifert, Gary D.

    2003-09-16T23:59:59.000Z

    A small sized electro-optic voltage sensor capable of accurate measurement of high voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation. A polarization beam displacer separates the input beam into two beams with orthogonal linear polarizations and causes one linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels effect elliptically polarizes the beam as it travels through the crystal. A reflector redirects the beam back through the crystal and the beam displacer. On the return path, the polarization beam displacer separates the elliptically polarized beam into two output beams of orthogonal linear polarization. The system may include a detector for converting the output beams into electrical signals and a signal processor for determining the voltage based on an analysis of the output beams.

  8. Interferometric fiber optic displacement sensor

    DOE Patents [OSTI]

    Farah, J.

    1999-04-06T23:59:59.000Z

    A method is presented to produce a change in the optical path length in the gap between two single mode optical fibers proportional to the lateral displacement of either fiber end normal to its axis. This is done with the use of refraction or diffraction at the interface between a guiding and non-guiding media to change the direction of propagation of the light in the gap. A method is also presented for laying a waveguide on a cantilever so that the displacement of the tip of the cantilever produces a proportional path length change in the gap by distancing the waveguide from the neutral axis of the cantilever. The fiber is supported as a cantilever or a waveguide is deposited on a micromachined cantilever and incorporated in an interferometer which is made totally on a silicon substrate with the use of integrated-optic technology. A resonant element in the form of a micro-bridge is incorporated in the ridge waveguide and produces a frequency output which is readily digitizeable and immune to laser frequency noise. Finally, monolithic mechanical means for phase modulation are provided on the same sensor substrate. This is done by vibrating the cantilever or micro-bridge either electrically or optically. 23 figs.

  9. Interferometric fiber optic displacement sensor

    DOE Patents [OSTI]

    Farah, John (M.I.T. P.O. Box 397301, Cambridge, MA 02139)

    1999-01-01T23:59:59.000Z

    A method is presented to produce a change in the optical path length in the gap between two single mode optical fibers proportional to the lateral displacement of either fiber end normal to its axis. This is done with the use of refraction or diffraction at the interface between a guiding and non-guiding media to change the direction of propagation of the light in the gap. A method is also presented for laying a waveguide on a cantilever so that the displacement of the tip of the cantilever produces a proportional path length change in the gap by distancing the waveguide from the neutral axis of the cantilever. The fiber is supported as a cantilever or a waveguide is deposited on a micromachined cantilever and incorporated in an interferometer which is made totally on a silicon substrate with the use of integrated-optic technology. A resonant element in the form of a micro-bridge is incorporated in the ridge waveguide and produces a frequency output which is readily digitizeable and immune to laser frequency noise. Finally, monolithic mechanical means for phase modulation are provided on the same sensor substrate. This is done by vibrating the cantilever or micro-bridge either electrically or optically.

  10. Optical Sensor Technology Development and Deployment

    SciTech Connect (OSTI)

    B. G. Parker

    2005-01-24T23:59:59.000Z

    The objectives of this ESP (Enhanced Surveillance) project are to evaluate sensor performance for future aging studies of materials, components and weapon systems. The goal of this project is to provide analysis capability to experimentally identify and characterize the aging mechanisms and kinetics of Core Stack Assembly (CSA) materials. The work on fiber optic light sources, hermetic sealing of fiber optics, fiber optic hydrogen sensors, and detection systems will be discussed.

  11. Temperature Sensor Data Michael W. Bigrigg

    E-Print Network [OSTI]

    Sadeh, Norman M.

    in the room. Sensor networks can be used to identify larger trends in temperature which could be used to report energy usage, HVAC problems, computer failures based on high temperatures, and fire evacuation

  12. NONNEGATIVE UNMIXING METHODOLOGY APPLIED ON BRILLOUIN OPTICAL FIBER SENSOR

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    NONNEGATIVE UNMIXING METHODOLOGY APPLIED ON BRILLOUIN OPTICAL FIBER SENSOR Edouard Buchoud1 As a complement to conventional sensors, Distributed Optical Fiber Sensors (DOFS) have gradually played. In complementary to traditional sensors, distributed fiber optic sensors (DOFS) are an attractive tool for SHM [1

  13. Electro-optic high voltage sensor

    DOE Patents [OSTI]

    Davidson, James R. (Idaho Falls, ID); Seifert, Gary D. (Idaho Falls, ID)

    2002-01-01T23:59:59.000Z

    A small sized electro-optic voltage sensor capable of accurate measurement of high levels of voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation into the sensor. A polarization beam displacer serves as a filter to separate the input beam into two beams with orthogonal linear polarizations. The beam displacer is oriented in such a way as to rotate the linearly polarized beams such that they enter a Pockels crystal having at a preferred angle of 45 degrees. The beam displacer is therefore capable of causing a linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels electro-optic effect induces a differential phase shift on the major and minor axes of the input beam as it travels through the Pockels crystal, which causes the input beam to be elliptically polarized. A reflecting prism redirects the beam back through the crystal and the beam displacer. On the return path, the polarization beam displacer separates the elliptically polarized beam into two output beams of orthogonal linear polarization representing the major and minor axes. The system may include a detector for converting the output beams into electrical signals, and a signal processor for determining the voltage based on an analysis of the output beams. The output beams are amplitude modulated by the frequency of the electric field and the amplitude of the output beams is proportional to the magnitude of the electric field, which is related to the voltage being measured.

  14. Reactive Grasping Using Optical Proximity Sensors

    E-Print Network [OSTI]

    Nangeroni, Paul

    We propose a system for improving grasping using fingertip optical proximity sensors that allows us to perform online grasp adjustments to an initial grasp point without requiring premature object contact or regrasping ...

  15. Mechanical and optical behavior of a novel optical fiber crack sensor and an interferometric strain sensor

    E-Print Network [OSTI]

    Olson, Noah Gale, 1969-

    2002-01-01T23:59:59.000Z

    The proper interpretation of measurements from an optical fiber sensor requires a full understanding of its mechanical response to external action and the corresponding change in optical output. To quantify the mechanical ...

  16. New Optimal Sensor Suite for Ultrahigh Temperature Fossil Fuel Applications

    SciTech Connect (OSTI)

    John Coggin; Jonas Ivasauskas; Russell G. May; Michael B. Miller; Rena Wilson

    2006-09-30T23:59:59.000Z

    Accomplishments during Phase II of a program to develop and demonstrate photonic sensor technology for the instrumentation of advanced powerplants are described. The goal of this project is the research and development of advanced, robust photonic sensors based on improved sapphire optical waveguides, and the identification and demonstration of applications of the new sensors in advanced fossil fuel power plants, where the new technology will contribute to improvements in process control and monitoring. During this program work period, major progress has been experienced in the development of the sensor hardware, and the planning of the system installation and operation. The major focus of the next work period will be the installation of sensors in the Hamilton, Ohio power plant, and demonstration of high-temperature strain gages during mechanical testing of SOFC components.

  17. Optical Fiber Sensor Technologies for Efficient and Economical Oil Recovery

    SciTech Connect (OSTI)

    Wang, a.; Pickrell, G.; Xiao, H.; May, r.

    2003-02-27T23:59:59.000Z

    The overall goal of this project was to develop reliable cost effective sensors for application in the down-hole environment. The physical parameters measured by these sensors were temperature, pressure, flow and acoustic signals. Sensor head configurations for each of the physical measurands were optimized to increase the sensitivity to the particular measurand of interest while decreasing the cross-sensitivity to the other physical measurands and to environmental influences. In addition, the optical signal demodulation electronics was designed to be insensitive to environmental influences while maintaining the required resolution, precision and accuracy of the parameter being sensed. The influence of potentially detrimental agents such as water in the down-hole environment was investigated as well as methods to protect both the optical fiber and the sensor from these detrimental effects.

  18. Electro-optic voltage sensor head

    DOE Patents [OSTI]

    Crawford, Thomas M. (Idaho Falls, ID); Davidson, James R. (Idaho Falls, ID); Woods, Gregory K. (Cornelius, OR)

    1999-01-01T23:59:59.000Z

    The invention is an electro-optic voltage sensor head designed for integration with existing types of high voltage transmission and distribution apparatus. The sensor head contains a transducer, which comprises a transducing material in which the Pockels electro-optic effect is observed. In the practice of the invention at least one beam of electromagnetic radiation is routed into the transducing material of the transducer in the sensor head. The beam undergoes an electro-optic effect in the sensor head when the transducing material is subjected to an E-field. The electro-optic effect is observed as a differential phase a shift, also called differential phase modulation, of the beam components in orthogonal planes of the electromagnetic radiation. In the preferred embodiment the beam is routed through the transducer along an initial axis and then reflected by a retro-reflector back substantially parallel to the initial axis, making a double pass through the transducer for increased measurement sensitivity. The preferred embodiment of the sensor head also includes a polarization state rotator and at least one beam splitter for orienting the beam along major and minor axes and for splitting the beam components into two signals which are independent converse amplitude-modulated signals carrying E-field magnitude and hence voltage information from the sensor head by way of optic fibers.

  19. Electro-optic voltage sensor head

    DOE Patents [OSTI]

    Crawford, T.M.; Davidson, J.R.; Woods, G.K.

    1999-08-17T23:59:59.000Z

    The invention is an electro-optic voltage sensor head designed for integration with existing types of high voltage transmission and distribution apparatus. The sensor head contains a transducer, which comprises a transducing material in which the Pockels electro-optic effect is observed. In the practice of the invention at least one beam of electromagnetic radiation is routed into the transducing material of the transducer in the sensor head. The beam undergoes an electro-optic effect in the sensor head when the transducing material is subjected to an E-field. The electro-optic effect is observed as a differential phase a shift, also called differential phase modulation, of the beam components in orthogonal planes of the electromagnetic radiation. In the preferred embodiment the beam is routed through the transducer along an initial axis and then reflected by a retro-reflector back substantially parallel to the initial axis, making a double pass through the transducer for increased measurement sensitivity. The preferred embodiment of the sensor head also includes a polarization state rotator and at least one beam splitter for orienting the beam along major and minor axes and for splitting the beam components into two signals which are independent converse amplitude-modulated signals carrying E-field magnitude and hence voltage information from the sensor head by way of optic fibers. 6 figs.

  20. Microbend fiber-optic chemical sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    2002-01-01T23:59:59.000Z

    A microbend fiber-optic chemical sensor for detecting chemicals in a sample, and a method for its use, is disclosed. The sensor comprises at least one optical fiber having a microbend section (a section of small undulations in its axis), for transmitting and receiving light. In transmission, light guided through the microbend section scatters out of the fiber core and interacts, either directly or indirectly, with the chemical in the sample, inducing fluorescence radiation. Fluorescence radiation is scattered back into the microbend section and returned to an optical detector for determining characteristics of the fluorescence radiation quantifying the presence of a specific chemical.

  1. Analogic fiber optic position sensor with nanometric resolution Frdric Lamarque

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Analogic fiber optic position sensor with nanometric resolution Frédéric Lamarque Université de of the sensor is presented as well as experimentation results. Keywords Fiber optic sensor, nanometric size is approximately 1.5x2.0x0.6 mm3 and the measurement resolution is 0.1 µm [4]. An optical sensor

  2. Ph.D. Thesis Optical Sensors Based on Dedicated

    E-Print Network [OSTI]

    Ph.D. Thesis Optical Sensors Based on Dedicated Diffractive Optical Elements STEVEN RICHARD KITCHEN;Abstract This thesis deals with the development of optical sensors based on laser diodes and dedicated part of the project deals with development of optical flow sensor systems. Firstly, a new beam splitter

  3. Magneto-optic current sensor

    DOE Patents [OSTI]

    Lanagan, Michael T.; Valsko-Vlasov, Vitalii K.; Fisher, Brandon L.; Welp, Ulrich

    2003-10-07T23:59:59.000Z

    An optical current transducer configured to sense current in the conductor is disclosed. The optical current transducer includes a light source and a polarizer that generates linearly polarized light received from a the light source. The light is communicated to a magneto-optic garnet that includes, among other elements, bismuth, iron and oxygen and is coupled to the conductor. The magneto-optic garnet is configured to rotate the polarization of the linearly polarized light received from the polarizer. The optical current transducer also includes an analyzer in optical communication with the magneto-optic garnet. The analyzer detects the rotation of the linearly polarized light caused by the magneto-optic garnet.

  4. CMOS temperature sensor utilizing interface-trap charge pumping 

    E-Print Network [OSTI]

    Berber, Feyza

    2006-10-30T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . . . . . . 57 35 (a) Expected value and (b) standard deviation (1sigma) of the sensor temperature readings with batch calibration . . . . . . . . . . . . . . 59 36 Sensitivity of the temperature sensor . . . . . . . . . . . . . . . . . . 60 1 CHAPTER I... which require built-in thermal sensors [1]. Semiconductor sensors are also preferred over traditional temperature sensors in some automotive and biomedical applications due to their low?area and low?cost. Semiconductor temperature sensors are generally...

  5. Lensless Magneto-optic speed sensor

    DOE Patents [OSTI]

    Veeser, Lynn R. (Los Alamos, NM); Forman, Peter R. (Los Alamos, NM); Rodriguez, Patrick J. (Santa Fe, NM)

    1998-01-01T23:59:59.000Z

    Lensless magneto-optic speed sensor. The construction of a viable Faraday sensor has been achieved. Multimode fiber bundles are used to collect the light. If coupled directly into a 100 or 200 .mu.m core fiber, light from a light emitting diode (LED) is sufficient to operate the sensor. In addition, LEDs ensure that no birefringence effects in the input fiber are possible, as the output from such light sources have random polarization. No lens is required since the large diameter optical fibers and thin crystals of materials having high Verdet constants (such as iron garnets) employed permit the collection of a substantial quantity of light. No coupler is required. The maximum amount of light which could reach a detector using a coupler is 25%, while the measured throughput of the fiber-optic bundle without a coupler is about 42%. All of the elements employed in the present sensor are planar, and no particular orientation of these elements is required. The present sensor operates over a wide range of distances from magnetic field sources, and observed signals are large. When a tone wheel is utilized, the signals are independent of wheel speed, and the modulation is observed to be about 75%. No sensitivity to bends in the input or output optical fiber leads was observed. Reliable operation was achieved down to zero frequency, or no wheel rotation.

  6. Lensless magneto-optic speed sensor

    DOE Patents [OSTI]

    Veeser, L.R.; Forman, P.R.; Rodriguez, P.J.

    1998-02-17T23:59:59.000Z

    Lensless magneto-optic speed sensor is disclosed. The construction of a viable Faraday sensor has been achieved. Multimode fiber bundles are used to collect the light. If coupled directly into a 100 or 200 {micro}m core fiber, light from a light emitting diode (LED) is sufficient to operate the sensor. In addition, LEDs ensure that no birefringence effects in the input fiber are possible, as the output from such light sources have random polarization. No lens is required since the large diameter optical fibers and thin crystals of materials having high Verdet constants (such as iron garnets) employed permit the collection of a substantial quantity of light. No coupler is required. The maximum amount of light which could reach a detector using a coupler is 25%, while the measured throughput of the fiber-optic bundle without a coupler is about 42%. All of the elements employed in the present sensor are planar, and no particular orientation of these elements is required. The present sensor operates over a wide range of distances from magnetic field sources, and observed signals are large. When a tone wheel is utilized, the signals are independent of wheel speed, and the modulation is observed to be about 75%. No sensitivity to bends in the input or output optical fiber leads was observed. Reliable operation was achieved down to zero frequency, or no wheel rotation. 5 figs.

  7. Fiber-optic displacement sensor system 

    E-Print Network [OSTI]

    Cava, Norayda Nora

    1990-01-01T23:59:59.000Z

    . 54 CHAPTER I INTRODUCTION The implementation of fiber optics in sensor systems is not a new idea; its popularity has steadily increased through the years. Although technological advances have much to do with this, certain characteristic.... The microbending scheme for displacement measurements [10], [11] takes advantage of the fact that when optical fibers are bent at sharp angles, energy will escape through the bent fiber walls. Maximum sensitivity for this scheme is achieved by minimizing...

  8. Biocompatible Force Sensor with Optical Readout and Dimensions of

    E-Print Network [OSTI]

    Straight, Aaron

    Biocompatible Force Sensor with Optical Readout and Dimensions of 6 nm3 Hari Shroff,,§ Bjo1rn M Received June 6, 2005 ABSTRACT We have developed a nanoscopic force sensor with optical readout. The sensor energy transfer. The sensor was calibrated between 0 and 20 pN using a combined magnetic tweezers

  9. CHARACTERIZATION OF AN OPTICAL COLLISION AVOIDANCE SENSOR Kyle Watters

    E-Print Network [OSTI]

    Hornsey, Richard

    CHARACTERIZATION OF AN OPTICAL COLLISION AVOIDANCE SENSOR Kyle Watters , Cyrus Minwalla , Michael, unmanned aerial vehicles, sensor ar- ray 1. INTRODUCTION A prototype optical instrument is described detection' should be at a distance on the order of 5 km [2]. An optical sensor may have advantages in mass

  10. Fiber Optic Sensors for PEM Fuel Cells Nigel David

    E-Print Network [OSTI]

    Victoria, University of

    Fiber Optic Sensors for PEM Fuel Cells by Nigel David B.Sc., Simon Fraser University, 2004 M or other means, without the permission of the author. #12;ii Fiber Optic Sensors for PEM Fuel Cells) and air- water two-phase flow sensors are developed and demonstrated based on optical fibre Bragg gratings

  11. Fiber-optic oxygen sensor using molybdenum chloride cluster luminescence

    E-Print Network [OSTI]

    Ghosh, Ruby N.

    Fiber-optic oxygen sensor using molybdenum chloride cluster luminescence Ruby N. Ghosh,a) Gregory L on a reflection-mode fiber-optic oxygen sensor based on the 3 O2 quenching of the red emission from hexanuclear, and medical applications. In these en- vironments the advantages of fiber-optic chemical sensors are that they

  12. ADHESIVE DISBOND MONITORING WITH MICROSTRUCTURED OPTICAL FIBER BRAGG GRATING SENSORS

    E-Print Network [OSTI]

    Boyer, Edmond

    ADHESIVE DISBOND MONITORING WITH MICROSTRUCTURED OPTICAL FIBER BRAGG GRATING SENSORS Sanne a sensing system that is based on a combination of 3 optical fiber sensors which are non optical fiber and feature an enhanced response to shear stress. The change in response of the sensors

  13. INTRODUCTION Optical sensors have long been used in the Great

    E-Print Network [OSTI]

    INTRODUCTION Optical sensors have long been used in the Great Lakes to track changes Concentrations Measured by Acoustic and Optical Sensors Nathan Hawley* Great Lakes Environmental Research sensitive to particles of different sizes, the simultaneous deployment of acoustic and optical sensors may

  14. Optical fiber sensors for harsh environments

    DOE Patents [OSTI]

    Xu, Juncheng; Wang, Anbo

    2007-02-06T23:59:59.000Z

    A diaphragm optic sensor comprises a ferrule including a bore having an optical fiber disposed therein and a diaphragm attached to the ferrule, the diaphragm being spaced apart from the ferrule to form a Fabry-Perot cavity. The cavity is formed by creating a pit in the ferrule or in the diaphragm. The components of the sensor are preferably welded together, preferably by laser welding. In some embodiments, the entire ferrule is bonded to the fiber along the entire length of the fiber within the ferrule; in other embodiments, only a portion of the ferrule is welded to the fiber. A partial vacuum is preferably formed in the pit. A small piece of optical fiber with a coefficient of thermal expansion chosen to compensate for mismatches between the main fiber and ferrule may be spliced to the end of the fiber.

  15. Sensors and Actuators A xxx (2004) xxxxxx Micromachined silicon force sensor based on diffractive optical

    E-Print Network [OSTI]

    Quake, Stephen R.

    2004-01-01T23:59:59.000Z

    that is designed to only be sensitive to axial deflections of the probe. The optical-encoder force sensor exhibits­membrane interactions under various physiological conditions. The force sensor is an optical encoder based on transSensors and Actuators A xxx (2004) xxx­xxx Micromachined silicon force sensor based on diffractive

  16. Fiber optics spectrochemical emission sensors

    DOE Patents [OSTI]

    Griffin, J.W.; Olsen, K.B.

    1992-02-04T23:59:59.000Z

    A method is described of in situ monitoring of a body of a fluid stored in a tank or groundwater or vadose zone gases in a well for the presence of selected chemical species. The method uses a probe insertable into the well or tank via a cable and having an electrical apparatus for exciting selected chemical species in the body of fluid. The probe can have a pair of electrodes for initiating a spark or a plasma cell for maintaining a plasma to excite the selected chemical species. The probe also has an optical apparatus for receiving optical emissions emitted by the excited species and optically transmitting the emissions via the cable to an analysis location outside the well. The analysis includes detecting a selected wavelength in the emissions indicative of the presence of the selected chemical species. A plurality of probes can be suspended at an end of a respective cable, with the transmitting and analyzing steps for each probe being synchronized sequentially for one set of support equipment and instrumentation to monitor at multiple test points. The optical apparatus is arranged about the light guide axis so that the selected chemical species are excited in the fluid in alignment with the light guide axis. Optical emissions are received from the excited chemical species along such axis. 18 figs.

  17. Fiber optics spectrochemical emission sensors

    DOE Patents [OSTI]

    Griffin, Jeffrey W. (Kennewick, WA); Olsen, Khris B. (West Richland, WA)

    1992-01-01T23:59:59.000Z

    A method of in situ monitoring of a body of a fluid stored in a tank or groundwater or vadose zone gases in a well for the presence of selected chemical species uses a probe insertable into the well or tank via a cable and having electrical apparatus for exciting selected chemical species in the body of fluid. The probe can have a pair of electrodes for initiating a spark or a plasma cell for maintaining a plasma to excite the selected chemical species. The probe also has optical apparatus for receiving optical emissions emitted by the excited species and optically transmitting the emissions via the cable to an analysis location outside the well. The analysis includes detecting a selected wavelength in the emissions indicative of the presence of the selected chemical species. A plurality of probes can be suspended at an end of a respective cable, with the transmitting and analyzing steps for each probe being synchronized sequentially for one set of support equipment and instrumentation to monitor at multiple test points. The optical apparatus is arranged about the light guide axis so that the selected chemical species are excited the fluid in alignment with the light guide axis and optical emissions are received from the excited chemical species along such axis.

  18. Electro-optical voltage sensor head

    DOE Patents [OSTI]

    Woods, Gregory K. (Idaho Falls, ID)

    1998-01-01T23:59:59.000Z

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  19. Multiplexed Sensor for Synthesis Gas Compsition and Temperature

    SciTech Connect (OSTI)

    Steven Buckley; Reza Gharavi; Marco Leon

    2007-10-01T23:59:59.000Z

    The overall goal of this project has been to develop a highly sensitive, multiplexed TDL-based sensor for CO{sub 2}, CO, H{sub 2}O (and temperature), CH{sub 4}, H{sub 2}S, and NH{sub 3}. Such a sensor was designed with so-called 'plug-and-play' characteristics to accommodate additional sensors, and provided in situ path-integrated measurements indicative of average concentrations at speeds suitable for direct gasifier control. The project developed the sensor and culminated in a real-world test of the underlying technology behind the sensor. During the project, new underlying measurements of spectroscopic constants for all of the gases of interest performed, in custom cells built for the project. The envisioned instrument was built from scratch from component lasers, fiber optics, amplifier blocks, detectors, etc. The sensor was tested for nearly a week in an operational power plant. The products of this research are expected to have a direct impact on gasifier technology and the production of high-quality syngas, with substantial broader application to coal and other energy systems. This report is the final technical report on project DE-FG26-04NT42172. During the project we completed all of the milestones planned in the project, with a modification of milestone (7) required due to lack of funding and personnel.

  20. All-optical Fog Sensor for Determining the Fog Visibility Range in Optical Wireless Communication Links

    E-Print Network [OSTI]

    Haddadi, Hamed

    All-optical Fog Sensor for Determining the Fog Visibility Range in Optical Wireless Communication is to use an all optical based fog sensor to study the atmospheric visibility of fog and its constituents on the optical wireless communication (OWC) links in a controlled laboratory test-bid. The fog sensor measures

  1. Dynamic Fiber Optic Sensors Under Intense Radioactive Environments

    SciTech Connect (OSTI)

    Allison, S.W.; Earl, D.D.; Haines, J.R.; Tsai, C.C.

    1998-10-15T23:59:59.000Z

    A liquid mercury target will be used as the neutron source for the proposed Spallation Neutron Source facility. This target is subjected to bombardment by short-pulse, high-energy proton beams. The intense thermal loads caused by interaction of the pulsed proton beam with the mercury create an enormous rate of temperature rise ({approximately}10{sup 7} K/s) during a very brief beam pulse ({approximately } 0.5 {micro}s). The resulting pressure waves in the mercury will interact with the walls of the mercury target and may lead to large stresses. To gain confidence in the mercury target design concept and to benchmark the computer design codes, we tested various electrical and optical sensors for measuring the transient strains on the walls of a mercury container and the pressures in the mercury. The sensors were attached on several sample mercury targets that were tested at various beam facilities: Oak Ridge Electron Linear Accelerator, Los Alamos Neutron Science Center-Weapons Neutron Research, and Brookhaven National Laboratory's Alternating Gradient Synchrotron. The effects of intense background radiation on measured signals for each sensor are described and discussed. Preliminary results of limited tests at these facilities indicate that the fiber optic sensors function well in this intense radiation environment, whereas conventional electrical sensors are dysfunctional.

  2. University of Illinois Temperature Sensors

    SciTech Connect (OSTI)

    K. L. Davis; D. L. Knudson; J. L. Rempe; B. M. Chase

    2014-09-01T23:59:59.000Z

    This document summarizes background information and presents results related to temperature measurements in the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) University of Illinois Project 29609 irradiation. The objective of this test was to assess the radiation performance of ferritic alloys for advanced reactor applications. The FeCr-based alloy system is considered the lead alloy system for a variety of advanced reactor components and applications. Irradiations of FeCr alloy samples were performed using the Hydraulic Shuttle Irradiation System (HSIS) in the B-7 position and in a static capsule in the A-11 position of the ATR.

  3. Fluorescent optical liquid level sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    2001-01-01T23:59:59.000Z

    A liquid level sensor comprising a transparent waveguide containing fluorescent material that is excited by light of a first wavelength and emits at a second, longer wavelength. The upper end of the waveguide is connected to a light source at the first wavelength through a beveled portion of the waveguide such that the input light is totally internally reflected within the waveguide above an air/liquid interface in a tank but is transmitted into the liquid below this interface. Light is emitted from the fluorescent material only in those portions of the waveguide that are above the air/liquid interface, to be collected at the upper end of the waveguide by a detector that is sensitive only to the second wavelength. As the interface moves down in the tank, the signal strength from the detector will increase.

  4. Cloaking a sensor via transformation optics

    E-Print Network [OSTI]

    Allan Greenleaf; Yaroslav Kurylev; Matti Lassas; Gunther Uhlmann

    2010-11-14T23:59:59.000Z

    It is generally believed that transformation optics based cloaking, besides rendering the cloaked region invisible to detection by scattering of incident waves, also shields the region from those same waves. We demonstrate a coupling between the cloaked and uncloaked regions, exposing a difference between cloaking for rays and waves. Interior resonances allow this coupling to be amplified, and careful choice of parameters leads to effective cloaks with degraded shielding. As one application, we describe how to use transformation optics to hide sensors in the cloaked region and yet enable the sensors to efficiently measure waves incident on the exterior of the cloak, an effect similar to the plasmon based approach of Alu' and Engheta.

  5. INTERFACIAL STABILITY OF THIN FILM FIBER-OPTIC HYDROGEN SENSORS

    E-Print Network [OSTI]

    INTERFACIAL STABILITY OF THIN FILM FIBER-OPTIC HYDROGEN SENSORS R. Davis Smith, Ping Liu, Se and utility of these sensors, especially in the configuration that is based upon the optical response hydrogen sensors for use as safety monitors wherever hydrogen is used, stored, or produced. Prior work has

  6. Optical Fiber Sensor Instrumentation for Slagging Coal Gasifiers

    SciTech Connect (OSTI)

    Anbo Wang; Kristie Cooper

    2008-07-19T23:59:59.000Z

    Coal gasifier is one of the most promising solutions for clean fossil energy. Refractory thickness monitoring and online real-time temperature measurement is needed for improved reliability and advanced process control for current and future generation power plants. The objective of this program is to design and implement an optical fiber based sensing system that could potentially be used to monitor refractory wall thickness and temperature inside a coal gasifier. For the thickness monitoring, the system should be able to operate at temperatures up to 1000 C. For this temperature range, silica fiber can still work so it is chosen for the sensor design. The measurement is based on a photon counting optical time domain reflectometer. A narrow light pulse is launched into a silica fiber which could be embedded into the gasifier refractory wall, and is partially reflected by the far end of the fiber. The time of flight of the light pulse in the fiber then gives an indication of the position of the fiber end, which is a function of the wall thickness when the fiber is embedded. Results obtained show a measurement accuracy of {+-}2cm in environment of 1000 C with a saw cut fiber end. When the fiber end is corroded by sodium carbide at 900 C, the accuracy is {+-}3cm. For the temperature measurement, a single crystal sapphire fiber sensor is designed. The sapphire fiber guides the broadband light from a light emitting diode to a sapphire wafer functioning as a Fabry-Perot interferometer and the wafer optical thickness is a function of temperature. The returned optical signal is then demodulated by multimode fiber based whitelight interferometry. The system was tested up to 1500 C with a measurement accuracy of {+-}10 C for the entire measurement range.

  7. A fibre optic sensor for the in situ determination of rock physical properties

    E-Print Network [OSTI]

    Reinsch, Thomas; Milsch, Harald; Bremer, Kort; Lewis, Elfed; Leen, Gabriel; Lochmann, Steffen; 10.1016/j.ijrmms.2012.06.011

    2012-01-01T23:59:59.000Z

    To understand the behaviour of rocks under changing load or temperature conditions, the determination of physical parameters like pore pressure or temperature within the pore space is essential. Within this study, the implementation of a novel fibre optic point sensor for pressure and temperature determination into a high pressure / high temperature triaxial cell is presented. For the first time, pressure was measured directly within the pore space of a Flechtinger sandstone specimen during a hydrostatic compression test at up to 70 MPa. The sensor used within this study consists of a miniature all-silica fibre optic Extrinsic Fabry-Perot Interferometer (EFPI) sensor which has an embedded Fibre Bragg Grating (FBG) reference sensor element to determine temperature and pressure directly at the point of measurement.

  8. Ultra-High Temperature Distributed Wireless Sensors

    SciTech Connect (OSTI)

    May, Russell; Rumpf, Raymond; Coggin, John; Davis, Williams; Yang, Taeyoung; O'Donnell, Alan; Bresnahan, Peter

    2013-03-31T23:59:59.000Z

    Research was conducted towards the development of a passive wireless sensor for measurement of temperature in coal gasifiers and coal-fired boiler plants. Approaches investigated included metamaterial sensors based on guided mode resonance filters, and temperature-sensitive antennas that modulate the frequency of incident radio waves as they are re-radiated by the antenna. In the guided mode resonant filter metamaterial approach, temperature is encoded as changes in the sharpness of the filter response, which changes with temperature because the dielectric loss of the guided mode resonance filter is temperature-dependent. In the mechanically modulated antenna approach, the resonant frequency of a vibrating cantilever beam attached to the antenna changes with temperature. The vibration of the beam perturbs the electrical impedance of the antenna, so that incident radio waves are phase modulated at a frequency equal to the resonant frequency of the vibrating beam. Since the beam resonant frequency depends on temperature, a Doppler radar can be used to remotely measure the temperature of the antenna. Laboratory testing of the guided mode resonance filter failed to produce the spectral response predicted by simulations. It was concluded that the spectral response was dominated by spectral reflections of radio waves incident on the filter. Laboratory testing of the mechanically modulated antenna demonstrated that the device frequency shifted incident radio waves, and that the frequency of the re-radiated waves varied linearly with temperature. Radio wave propagation tests in the convection pass of a small research boiler plant identified a spectral window between 10 and 13 GHz for low loss propagation of radio waves in the interior of the boiler.

  9. Cloaking a Sensor via Transformation Optics Allan Greenleaf

    E-Print Network [OSTI]

    Uhlmann, Gunther

    LM11852 REV IEW CO PY N O T FO R D ISTRIBU TIO N Cloaking a Sensor via Transformation Optics Allan. As one application, we describe how to use transformation optics to hide sensors in the cloaked region optics cloaking at positive frequency, besides rendering the cloaked region invisible to detection

  10. Intensity Histogram CMOS Image Sensor for Adaptive Optics

    E-Print Network [OSTI]

    Cauwenberghs, Gert

    Intensity Histogram CMOS Image Sensor for Adaptive Optics Yu M. Chi, Gary Carhart , Mikhail AAODisturbanceSource Update/Optimize Fig. 1. Intended real-time optical control application. The sensor computes histogram of Bioengineering University of California, San Diego La Jolla, CA 92093 Intelligent Optics Lab U.S. Army Research

  11. Modeling and validation of performance limitations for the optimal design of interferometric and intensity-modulated fiber optic displacement sensors

    E-Print Network [OSTI]

    Moro, Erik Allan

    2012-01-01T23:59:59.000Z

    317 (1996). B. Culshaw, “Optical fiber sensor technologies:Fabry-Perot optical fiber sensors,” Opt. Lett. 16 ( 4), 273-and implementation of optical sensors for use in such

  12. Pendulum Sensor using an Optical Mouse

    E-Print Network [OSTI]

    Randall D. Peters; Sheng-Chiang "John" Lee

    2009-04-20T23:59:59.000Z

    An optical mouse that is in common use with personal computers is employed to measure the motion of a pendulum. The pendulum can be monitored (i) realtime only, or (ii) also with data storage for later detailed analysis using Excel. The software developed for this purpose is a LabView executable algorithm. It allows the user to select among several modes that include filtering operations. The limiting resolution of this position sensor, which is in the neighborhood of 50 micrometers, is determined by the 'dpi' specification of the mouse.

  13. Waveguide-based optical chemical sensor

    DOE Patents [OSTI]

    Grace, Karen M. (Ranchos de Taos, NM); Swanson, Basil I. (Los Alamos, NM); Honkanen, Seppo (Tucson, AZ)

    2007-03-13T23:59:59.000Z

    The invention provides an apparatus and method for highly selective and sensitive chemical sensing. Two modes of laser light are transmitted through a waveguide, refracted by a thin film host reagent coating on the waveguide, and analyzed in a phase sensitive detector for changes in effective refractive index. Sensor specificity is based on the particular species selective thin films of host reagents which are attached to the surface of the planar optical waveguide. The thin film of host reagents refracts laser light at different refractive indices according to what species are forming inclusion complexes with the host reagents.

  14. Signal processing for fiber optic acoustic sensor system

    E-Print Network [OSTI]

    Zhu, Juhong

    2000-01-01T23:59:59.000Z

    pulses from a single mode laser. Signals from multiple sensors in the array are separated and demultiplexed. The acoustic pressure information is determined by processing the returned optical pulses using a fiber Mach-Zehnder interferometer as an optical...

  15. Temperature compensated current sensor using reference magnetic field

    DOE Patents [OSTI]

    Yakymyshyn, Christopher Paul (Seminole, FL); Brubaker, Michael Allen (Loveland, CO); Yakymyshyn, Pamela Jane (Seminole, FL)

    2007-10-09T23:59:59.000Z

    A method is described to provide temperature compensation and self-calibration of a current sensor based on a plurality of magnetic field sensors positioned around a current carrying conductor. A reference magnetic field generated within the current sensor housing is detected by a separate but identical magnetic field sensor and is used to correct variations in the output signal due to temperature variations and aging.

  16. Excess optical quantum noise in atomic sensors

    E-Print Network [OSTI]

    Irina Novikova; Eugeniy E. Mikhailov; Yanhong Xiao

    2014-10-14T23:59:59.000Z

    Enhanced nonlinear optical response of a coherent atomic medium is the basis for many atomic sensors, and their performance is ultimately limited by the quantum fluctuations of the optical read-out. Here we demonstrate that off-resonant interactions can significantly modify the quantum noise of the optical field, even when their effect on the mean signal is negligible. We illustrate this concept by using an atomic magnetometer based on the nonlinear Faraday effect: the rotation of the light polarization is mainly determined by the resonant light-induced spin alignment, which alone does not change the photon statistics of the optical probe. Yet, we found that the minimum noise of output polarization rotation measurements is above the expected shot noise limit. This excess quantum noise is due to off-resonant coupling and grows with atomic density. We also show that the detection scheme can be modified to reduce the measured quantum noise (even below the shot-noise limit) but only at the expense of the reduced rotational sensitivity. These results show the existence of previously unnoticed factors in fundamental limitations in atomic magnetometry and could have impacts in many other atom-light based precision measurements.

  17. Side-emitting fiber optic position sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    2008-02-12T23:59:59.000Z

    A side-emitting fiber optic position sensor and method of determining an unknown position of an object by using the sensor. In one embodiment, a concentrated beam of light source illuminates the side of a side-emitting fiber optic at an unknown axial position along the fiber's length. Some of this side-illuminated light is in-scattered into the fiber and captured. As the captured light is guided down the fiber, its intensity decreases due to loss from side-emission away from the fiber and from bulk absorption within the fiber. By measuring the intensity of light emitted from one (or both) ends of the fiber with a photodetector(s), the axial position of the light source is determined by comparing the photodetector's signal to a calibrated response curve, look-up table, or by using a mathematical model. Alternatively, the side-emitting fiber is illuminated at one end, while a photodetector measures the intensity of light emitted from the side of the fiber, at an unknown position. As the photodetector moves further away from the illuminated end, the detector's signal strength decreases due to loss from side-emission and/or bulk absorption. As before, the detector's signal is correlated to a unique position along the fiber.

  18. Structure, Mechanism and Applications of Sol-Gel Clad Fiber-Optic Sensors

    E-Print Network [OSTI]

    Fellows Olteanu, Marta Sarah

    2010-01-01T23:59:59.000Z

    as a reversible optical sensor for ammonia and acidity [17],well suited to novel optical sensor applications [15][20][of chemical sensors which utilize optical waveguides and or/

  19. MICROSTRUCTURED OPTICAL FIBER BRAGG GRATING SENSORS FOR STRUCTURAL HEALTH MONITORING APPLICATIONS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    MICROSTRUCTURED OPTICAL FIBER BRAGG GRATING SENSORS FOR STRUCTURAL HEALTH MONITORING APPLICATIONS optical fiber Bragg grating (MOFBG) sensors for structural health monitoring applications. We then focus, optical fiber sensor, fiber Bragg grating, structural health monitoring INTRODUCTION Microstructured

  20. An optical water vapor sensor for unmanned aerial vehicles

    SciTech Connect (OSTI)

    Timothy A. Berkoff; Paul L. Kebabian; Robert A. McClatchy; Charles E. Kolb; Andrew Freedman

    1998-12-01T23:59:59.000Z

    The water vapor sensor developed by Aerodyne Research, based on the optical absorption of light at {approximately}935 nm, has been successfully demonstrated on board the Pacific Northwest National Laboratory's Gulfstream-1 research aircraft during the Department of Energy's ARM Intensive Operations Period in August 1998. Data taken during this field campaign show excellent agreement with a chilled mirror and Lyman-alpha hygrometers and measurements confirm the ability to measure rapid, absolute water vapor fluctuations with a high degree of instrument stability and accuracy, with a noise level as low 10 ppmv (1 Hz measurement bandwidth). The construction of this small, lightweight sensor contains several unique elements which result in several significant advantages when compared to other techniques. First, the low power consumption Argon discharge lamp provides an optical beam at a fixed wavelength without a need for temperature or precision current control. The multi-pass absorption cell developed for this instrument provides a compact, low cost method that can survive deployment in the field. Fiber-optic cables, which are used to convey to light between the absorption cell, light source, and detection modules enable remote placement of the absorption cell from the opto-electronics module. Finally, the sensor does not use any moving parts which removes a significant source of potential malfunction. The result is an instrument which maintained its calibration throughout the field measurement campaign, and was not affected by high vibration and large uncontrolled temperature excursions. We believe that the development of an accurate, fast response water vapor monitor described in this report will open up new avenues of aerial-vehicle-based atmospheric research which have been relatively unexplored due to the lack of suitable low-cost, light-weight instrumentation.

  1. Optical fiber pressure and acceleration sensor fabricated on a fiber endface

    DOE Patents [OSTI]

    Zhu, Yizheng; Wang, Xingwei; Xu, Juncheng; Wang, Anbo

    2006-05-30T23:59:59.000Z

    A fiber optic sensor has a hollow tube bonded to the endface of an optical fiber, and a diaphragm bonded to the hollow tube. The fiber endface and diaphragm comprise an etalon cavity. The length of the etalon cavity changes when applied pressure or acceleration flexes the diaphragm. The entire structure can be made of fused silica. The fiber, tube, and diaphragm can be bonded with a fusion splice. The present sensor is particularly well suited for measuring pressure or acceleration in high temperature, high pressure and corrosive environments (e.g., oil well downholes and jet engines). The present sensors are also suitable for use in biological and medical applications.

  2. Proceedings: 3rd EPRI Optical Sensor Systems Workshop

    SciTech Connect (OSTI)

    None

    2002-02-01T23:59:59.000Z

    These are the proceedings of the third Optical Sensor System Workshop, part of an ongoing effort by EPRI to support development of optical sensor technology, to identify benefits for utility users, and to position EPRI members as more ''informed buyers'' and users.

  3. Fibratus tactile sensor using reflection on an optical lever Satoshi Saga

    E-Print Network [OSTI]

    Tachi, Susumu

    Fibratus tactile sensor using reflection on an optical lever Satoshi Saga Tohoku University Shinobu this fibratus tactile sensor. Keywords: tactile sensor, fiber, image sensor, optical measure- ment, optical measure- ments; further, the wiring assembly is complicated. Some optical sensors [Yamada et al. 2002

  4. Evaluations of fiber optic sensors for interior applications

    SciTech Connect (OSTI)

    Sandoval, M.W.; Malone, T.P.

    1996-02-01T23:59:59.000Z

    This report addresses the testing and evaluation of commercial fiber optic intrusion detection systems in interior applications. The applications include laying optical fiber cable above suspended ceilings to detect removal of ceiling tiles, embedding optical fibers inside a tamper or item monitoring blanket that could be placed over an asset, and installing optical fibers on a door to detect movement or penetration. Detection capability of the fiber optic sensors as well as nuisance and false alarm information were focused on during the evaluation. Fiber optic sensor processing, system components, and system setup are described.

  5. High temperature thermometric phosphors for use in a temperature sensor

    DOE Patents [OSTI]

    Allison, Stephen W. (Knoxville, TN); Cates, Michael R. (Oak Ridge, TN); Boatner, Lynn A. (Oak Ridge, TN); Gillies, George T. (Earlysville, VA)

    1998-01-01T23:59:59.000Z

    A high temperature phosphor consists essentially of a material having the general formula LuPO.sub.4 :Dy.sub.(x),Eu.sub.(y), wherein: 0.1 wt %.ltoreq.x.ltoreq.20 wt % and 0.1 wt %.ltoreq.y.ltoreq.20 wt %. The high temperature phosphor is in contact with an article whose temperature is to be determined. The article having the phosphor in contact with it is placed in the environment for which the temperature of the article is to be determined. The phosphor is excited by a laser causing the phosphor to fluoresce. The emission from the phosphor is optically focused into a beam-splitting mirror which separates the emission into two separate emissions, the emission caused by the dysprosium dopant and the emission caused by the europium dopent. The separated emissions are optically filtered and the intensities of the emission are detected and measured. The ratio of the intensity of each emission is determined and the temperature of the article is calculated from the ratio of the intensities of the separate emissions.

  6. High temperature thermometric phosphors for use in a temperature sensor

    DOE Patents [OSTI]

    Allison, S.W.; Cates, M.R.; Boatner, L.A.; Gillies, G.T.

    1998-03-24T23:59:59.000Z

    A high temperature phosphor consists essentially of a material having the general formula LuPO{sub 4}:Dy{sub (x)},Eu{sub (y)}, wherein: 0.1 wt %{<=}x{<=}20 wt % and 0.1 wt %{<=}y{<=}20 wt %. The high temperature phosphor is in contact with an article whose temperature is to be determined. The article having the phosphor in contact with it is placed in the environment for which the temperature of the article is to be determined. The phosphor is excited by a laser causing the phosphor to fluoresce. The emission from the phosphor is optically focused into a beam-splitting mirror which separates the emission into two separate emissions, the emission caused by the dysprosium dopant and the emission caused by the europium dopant. The separated emissions are optically filtered and the intensities of the emission are detected and measured. The ratio of the intensity of each emission is determined and the temperature of the article is calculated from the ratio of the intensities of the separate emissions. 2 figs.

  7. doped Y3Al5O12, NaBi(WO4)2 and LiNbO3 crystals as optical temperature sensors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    the possible applications one should note temperature monitoring in highly corrosive media, electrical power OTS based on absorption coefficient ratio (ACR). Thus the capabilities of lithium niobate crystal

  8. Proceedings of IEEE Sensors 2003 Fiber Optic Oxygen Sensor for Power Plant Applications

    E-Print Network [OSTI]

    Ghosh, Ruby N.

    807 Proceedings of IEEE Sensors 2003 Paper 22-2 Fiber Optic Oxygen Sensor for Power Plant for power plant applications. The sensor utilizes quenching of the bright red fluorescence from inorganic. Motivation Combustion processes in power plants require the correct mix of fuel and oxygen to maximize

  9. doped Y3Al5O12, NaBi(WO4)2 and LiNbO3 crystals as optical temperature sensors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    the possible applications one should note temperature monitoring in highly corrosive media, electrical power ratio (ACR). Thus the capabilities of lithium niobate crystal doped with Yb3+ ions as a material for OTS

  10. A New Generation of Sensors Based on Extraordinary Optical Transmission

    E-Print Network [OSTI]

    Brolo, Alexandre G.

    A New Generation of Sensors Based on Extraordinary Optical Transmission REUVEN GORDON, DAVID SINTON advances in the optical and spectroscopic properties of nanohole arrays in thin gold films optical transmission" (EOT), that is, they are more transparent at certain wavelengths than expected

  11. Process Compensated CMOS Temperature Sensor for Microprocessor Application

    E-Print Network [OSTI]

    Ayazi, Farrokh

    Process Compensated CMOS Temperature Sensor for Microprocessor Application Yaesuk Jeong and Farrokh consumption is 478uW. I. INTRODUCTION With microprocessors scaling to higher performance and faster speed in the microprocessor to monitor its thermal distribution. Many CMOS based temperature sensors have been reported

  12. Lightweight Integrated Optical Sensor for Atmospheric Measurements on Mobile Platforms

    SciTech Connect (OSTI)

    Parameswaran, Krishnan R. [Physical Sciences Inc.

    2013-12-02T23:59:59.000Z

    The goal of the Phase I program was to develop a novel open path sensor platform technology based on integration of semiconductor waveguides with efficient optoelectronic components on a monolithic platform. The successful Phase I effort resulted in demonstration of a novel optical resonator structure based on semiconductor high contrast gratings (HCGs) that will enable implementation of an ultra-compact, low-power gas sensor suitable for use on mobile platforms. Extensive numerical modeling was performed to design a device optimized for measuring CO2 at a wavelength for which a laser was available for proof of concept. Devices were fabricated and tested to match the target wavelength, angle, and operating temperature. This demonstration is the first implementation of HCGs at the wavelengths of interest and shows the flexibility of the proposed architecture for gas sensing applications. The measured cavity Q was lower than anticipated due to fabrication process challenges. The PSI and UC Berkeley team has identified solutions to these challenges and will produce optimized devices in a Phase II program where a prototype sensor will be fabricated and tested.

  13. Self-compensating fiber optic flow sensor having an end of a fiber optics element and a reflective surface within a tube

    DOE Patents [OSTI]

    Peng, Wei; Qi, Bing; Wang, Anbo

    2006-05-16T23:59:59.000Z

    A flow rate fiber optic transducer is made self-compensating for both temperature and pressure by using preferably well-matched integral Fabry-Perot sensors symmetrically located around a cantilever-like structure. Common mode rejection signal processing of the outputs allows substantially all effects of both temperature and pressure to be compensated. Additionally, the integral sensors can individually be made insensitive to temperature.

  14. Novel fiber optic polarimetric torsion sensor based on polarization-maintaining photonic crystal fiber

    E-Print Network [OSTI]

    Wai, Ping-kong Alexander

    Novel fiber optic polarimetric torsion sensor based on polarization- maintaining photonic crystal other engineering applications. Compared with conventional torsion sensors, the fiber optic torsion sensors have the distinct advantages of all-fiber-optical sensing. The fiber optic torsion sensors based

  15. Distributed fiber optic intrusion sensor system for monitoring long perimeters 

    E-Print Network [OSTI]

    Juarez, Juan C.

    2009-06-02T23:59:59.000Z

    A distributed sensor using an optical fiber for detecting and locating intruders over long perimeters (>10 km) is described. Phase changes resulting from either the pressure of the intruder on the ground immediately above the buried fiber or from...

  16. Fiber optic micromirror sensor for volatile organic compounds

    SciTech Connect (OSTI)

    Butler, M.A.; Ricco, A.J.; Buss, R. (Sandia National Lab., Albuquerque, NM (US))

    1990-04-01T23:59:59.000Z

    With the growing concern over environmental pollution, there is a need for sensors to locate and measure the distribution of a wide range of pollutants. In this paper the authors report a fiber optic sensor, based on a thin film micromirror, which responds to a wide range of volatile organic compounds (VOCs). This generic class of sensor will be useful for monitoring applications where the pollutant has already been identified.

  17. Optical sensors and multisensor arrays containing thin film electroluminescent devices

    DOE Patents [OSTI]

    Aylott, Jonathan W. (Ann Arbor, MI); Chen-Esterlit, Zoe (Ann Arbor, MI); Friedl, Jon H. (Ames, IA); Kopelman, Raoul (Ann Arbor, MI); Savvateev, Vadim N. (Ames, IA); Shinar, Joseph (Ames, IA)

    2001-12-18T23:59:59.000Z

    Optical sensor, probe and array devices for detecting chemical biological, and physical analytes. The devices include an analyte-sensitive layer optically coupled to a thin film electroluminescent layer which activates the analyte-sensitive layer to provide an optical response. The optical response varies depending upon the presence of an analyte and is detected by a photodetector and analyzed to determine the properties of the analyte.

  18. Fabry-Perot fiber optic sensor using multimode laser diode

    E-Print Network [OSTI]

    Chu, Siu Yi Andrew

    1993-01-01T23:59:59.000Z

    FABRY-PEROT FIBER OPTIC SENSOR USING MULTIMODE LASER DIODE A Thesis SIU YI ANDREW CHU Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August... 1993 Major Subject: Electrical Engineering FABRY-PEROT FIBER OPTIC SENSOR USING MULTIMODE LASER DIODE A Thesis SIU YI ANDREW CHU Submitted to Texas ARM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE...

  19. Cloaking a sensor for three-dimensional Maxwell's equations: transformation optics approach

    E-Print Network [OSTI]

    Chen, Xudong; Uhlmann, Gunther

    2011-01-01T23:59:59.000Z

    P. Sheng, “Transformation optics and metamaterials,” Nat.sensor via transformation optics,” Phys. Rev. E 83, 016603 (October 2011 / Vol. 19, No. 21 / OPTICS EXPRESS 20518 13. G.

  20. FEASIBILITY OF A STACK INTEGRATED SOFC OPTICAL CHEMICAL SENSOR

    SciTech Connect (OSTI)

    Michael A. Carpenter

    2004-03-30T23:59:59.000Z

    The work performed during the UCR Innovative Concepts phase I program was designed to demonstrate the chemical sensing capabilities of nano-cermet SPR bands at solid oxide fuel cell operating conditions. Key to this proposal is that the materials choice used a YSZ ceramic matrix which upon successful demonstration of this concept, will allow integration directly onto the SOFC stack. Under the Innovative Concepts Program the University at Albany Institute for Materials (UAIM)/UAlbany School of NanoSciences and NanoEngineering synthesized, analyzed and tested Pa, and Au doped YSZ nano-cermets as a function of operating temperature and target gas exposure (hydrogen, carbon monoxide and 1-dodecanethiol). During the aforementioned testing procedure the optical characteristics of the nano-cermets were monitored to determine the sensor selectivity and sensitivity.

  1. INTELLIGENT MONITORING SYSTEM WITH HIGH TEMPERATURE DISTRIBUTED FIBEROPTIC SENSOR FOR POWER PLANT COMBUSTION PROCESSES

    SciTech Connect (OSTI)

    Kwang Y. Lee; Stuart S. Yin; Andre Boheman

    2004-12-26T23:59:59.000Z

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, improvement was made on the performance of in-fiber grating fabricated in single crystal sapphire fibers, test was performed on the grating performance of single crystal sapphire fiber with new fabrication methods, and the fabricated grating was applied to high temperature sensor. Under Task 2, models obtained from 3-D modeling of the Demonstration Boiler were used to study relationships between temperature and NOx, as the multi-dimensionality of such systems are most comparable with real-life boiler systems. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we investigate a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. The 3D temperature data is furnished by the Penn State Energy Institute using FLUENT. Given a set of empirical data with no analytic expression, we first develop an analytic description and then extend that model along a single axis.

  2. High-Temperature Zirconia Oxygen Sensor with Sealed Metal/Metal...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High-Temperature Zirconia Oxygen Sensor with Sealed MetalMetal Oxide Internal Reference High-Temperature Zirconia Oxygen Sensor with Sealed MetalMetal Oxide Internal Reference...

  3. Extrinsic fiber optic displacement sensors and displacement sensing systems

    DOE Patents [OSTI]

    Murphy, K.A.; Gunther, M.F.; Vengsarkar, A.M.; Claus, R.O.

    1994-04-05T23:59:59.000Z

    An extrinsic Fizeau fiber optic sensor comprises a single-mode fiber, used as an input/output fiber, and a multimode fiber, used purely as a reflector, to form an air gap within a silica tube that acts as a Fizeau cavity. The Fresnel reflection from the glass/air interface at the front of the air gap (reference reflection) and the reflection from the air/glass interface at the far end of the air gap (sensing reflection) interfere in the input/output fiber. The two fibers are allowed to move in the silica tube, and changes in the air gap length cause changes in the phase difference between the reference reflection and the sensing reflection. This phase difference is observed as changes in intensity of the light monitored at the output arm of a fused biconical tapered coupler. The extrinsic Fizeau fiber optic sensor behaves identically whether it is surface mounted or embedded, which is unique to the extrinsic sensor in contrast to intrinsic Fabry-Perot sensors. The sensor may be modified to provide a quadrature phase shift extrinsic Fizeau fiber optic sensor for the detection of both the amplitude and the relative polarity of dynamically varying strain. The quadrature light signals may be generated by either mechanical or optical means. A plurality of the extrinsic sensors may connected in cascade and multiplexed to allow monitoring by a single analyzer. 14 figures.

  4. Extrinsic fiber optic displacement sensors and displacement sensing systems

    DOE Patents [OSTI]

    Murphy, Kent A. (Roanoke, VA); Gunther, Michael F. (Blacksburg, VA); Vengsarkar, Ashish M. (Scotch Plains, NJ); Claus, Richard O. (Christiansburg, VA)

    1994-01-01T23:59:59.000Z

    An extrinsic Fizeau fiber optic sensor comprises a single-mode fiber, used as an input/output fiber, and a multimode fiber, used purely as a reflector, to form an air gap within a silica tube that acts as a Fizeau cavity. The Fresnel reflection from the glass/air interface at the front of the air gap (reference reflection) and the reflection from the air/glass interface at the far end of the air gap (sensing reflection) interfere in the input/output fiber. The two fibers are allowed to move in the silica tube, and changes in the air gap length cause changes in the phase difference between the reference reflection and the sensing reflection. This phase difference is observed as changes in intensity of the light monitored at the output arm of a fused biconical tapered coupler. The extrinsic Fizeau fiber optic sensor behaves identically whether it is surface mounted or embedded, which is unique to the extrinsic sensor in contrast to intrinsic Fabry-Perot sensors. The sensor may be modified to provide a quadrature phase shift extrinsic Fizeau fiber optic sensor for the detection of both the amplitude and the relative polarity of dynamically varying strain. The quadrature light signals may be generated by either mechanical or optical means. A plurality of the extrinsic sensors may connected in cascade and multiplexed to allow monitoring by a single analyzer.

  5. Intrinsic Fabry-Perot optical fiber sensors and their multiplexing

    DOE Patents [OSTI]

    Wang, Anbo (Blacksburg, VA)

    2007-12-11T23:59:59.000Z

    An intrinsic Fabry-Perot optical sensor includes a thin film sandwiched between two fiber ends. When light is launched into the fiber, two reflections are generated at the two fiber/thin film interfaces due to a difference in refractive indices between the fibers and the film, giving rise to the sensor output. In another embodiment, a portion of the cladding of a fiber is removed, creating two parallel surfaces. Part of the evanescent fields of light propagating in the fiber is reflected at each of the surfaces, giving rise to the sensor output. In a third embodiment, the refractive index of a small portion of a fiber is changed through exposure to a laser beam or other radiation. Interference between reflections at the ends of the small portion give rise to the sensor output. Multiple sensors along a single fiber are multiplexed using an optical time domain reflectometry method.

  6. Multiplexed Optical Fiber Sensors for Coal Fired Advanced Fossil Energy Systems

    SciTech Connect (OSTI)

    Anbo Wang; Gary Pickrell

    2011-12-31T23:59:59.000Z

    This report summarizes technical progress on the program â??Multiplexed Optical Fiber Sensors for Coal Fired Advanced Fossil Energy Systemsâ? funded by the National Energy Technology Laboratory of the U.S. Department of Energy, and performed jointly by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering and the Department of Materials Science and Engineering at Virginia Tech. This three-year project started on October 1, 2008. In the project, a fiber optical sensing system based on intrinsic Fabry-Perot Interferometer (IFPI) was developed for strain and temperature measurements for Ultra Supercritical boiler condition assessment. Investigations were focused on sensor design, fabrication, attachment techniques and novel materials for high temperature and strain measurements. At the start of the project, the technical requirements for the sensing technology were determined together with our industrial partner Alstom Power. As is demonstrated in Chapter 4, all the technical requirements are successfully met. The success of the technology extended beyond laboratory test; its capability was further validated through the field test at DOE NETL, in which the sensors yielded distributed temperature mapping of a testing coupon installed in the turbine test rig. The measurement results agreed well with prior results generated with thermocouples. In this project, significant improvements were made to the IFPI sensor technology by splicing condition optimization, transmission loss reduction, sensor signal demodulation and sensor system design.

  7. Gallium Nitride Integrated Gas/Temperature Sensors for

    E-Print Network [OSTI]

    precision and accuracy · Field test for reliability and lifetime · 1) Sensor Needs and Requirements://www.ott.doe.gov/pdfs/sensor_needs.pdf #12;4 Approach GaN based devices and circuits are an attractive option for high temperature electronic) and hydrogen (30-70%) 80% Complete 2- Determine confounding effects due to multiple components 80% Complete 3

  8. Fiber optic hydrophone sensor arrays using low reflectance internal mirrors 

    E-Print Network [OSTI]

    Lee, Jong-Seo

    1998-01-01T23:59:59.000Z

    A new design of fiber optic hydrophone sensor arrays phics. using low reflectance internal mirrors in optical fibers is investigated. The mirrors are produced by fusion arc splicing of two fibers, one of which has a thin film of TiO2 on the end. A...

  9. Temperature Sensor Tag for Passive UHF RFID Systems

    E-Print Network [OSTI]

    Elsherbeni, Atef Z.

    Temperature Sensor Tag for Passive UHF RFID Systems Juha Virtanen, Leena Ukkonen, Toni Björninen of Mississippi University, MS 38677, USA atef@olemiss.edu Abstract--This paper presents a novel temperature is used as the temperature sensitive material instead of the more traditional semi-conducting materials

  10. High sensitivity bulk electro-optic modulator field sensor for high voltage environments

    E-Print Network [OSTI]

    Shy,Jow-Tsong

    High sensitivity bulk electro-optic modulator field sensor for high voltage environments Mao December 2004) An optical electric field sensor is an effective instrument for surveying the electric attacked by unexpected electrical shocks through the metal cable of the sensor. Sensing by optical sensors

  11. Fig. 1 Teleoperated slave robot Development of Distributed Optical Torque Sensors for Realization of Local Impedance

    E-Print Network [OSTI]

    Tachi, Susumu

    Fig. 1 Teleoperated slave robot Development of Distributed Optical Torque Sensors for Realization the recent development of optical torque sensor in order to replace expensive strain gauge sensor attached shapes of mechanical structure of sensor as well as optical measurement approaches are given. The results

  12. Sensors and Actuators B 123 (2007) 594605 Fiber optic sensing of liquid refractive index

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    Sensors and Actuators B 123 (2007) 594­605 Fiber optic sensing of liquid refractive index Argha rights reserved. Keywords: Liquid refractive index sensor; Fiber optic refractive index sensor; Refractive index sensitivity of uncladded fiber; Uncladded optical fiber as sensor 1. Introduction

  13. Informed peg-in-hole insertion using optical sensors Eric Paulos John Canny

    E-Print Network [OSTI]

    Paulos, Eric

    Informed peg-in-hole insertion using optical sensors Eric Paulos John Canny Department several very simple, inexpensive, and accurate optical sensors. The self-calibrating feature allows us operations using simple optical sensors. A key to the method is the use of one sensor to compute the position

  14. Intelligent Monitoring System With High Temperature Distributed Fiberoptic Sensor For Power Plant Combustion Processes

    SciTech Connect (OSTI)

    Kwang Y. Lee; Stuart S. Yin; Andre Boheman

    2005-12-26T23:59:59.000Z

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, we set up a dedicated high power, ultrafast laser system for fabricating in-fiber gratings in harsh environment optical fibers, successfully fabricated gratings in single crystal sapphire fibers by the high power laser system, and developed highly sensitive long period gratings (lpg) by electric arc. Under Task 2, relevant mathematical modeling studies of NOx formation in practical combustors. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we investigate a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. The 3D temperature data is furnished by the Penn State Energy Institute using FLUENT. Given a set of empirical data with no analytic expression, we first develop an analytic description and then extend that model along a single axis. Extrapolation capability was demonstrated for estimating enthalpy in a power plant.

  15. Optics-less Sensors for Localization of Radiation Sources

    E-Print Network [OSTI]

    H. J. Caulfield; L. P. Yaroslavsky; Ch. Goerzen; S. Umansky

    2008-08-08T23:59:59.000Z

    A new family of radiation sensors is introduced which do not require any optics. The sensors consist of arrays of elementary sub-sensors with natural cosine-law or similar angular sensitivity supplemented with a signal processing unit that computes optimal statistical estimations of source parameters. We show, both theoretically and by computer simulation, that such sensors are capable of accurate localization and intensity estimation of a given number of radiation sources and of imaging of a given number of sources in known positions. The accuracy is found to be dependent only on the sub-sensors noise level, on the number of sub-sensors and on the spacing between radiation sources.

  16. Optical temperature indicator using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1995-01-01T23:59:59.000Z

    A reversible optical temperature indicator utilizes thermochromic semiconductors which vary in color in response to various temperature levels. The thermochromic material is enclosed in an enamel which provides protection and prevents breakdown at higher temperatures. Cadmium sulfide is the preferred semiconductor material. The indicator may be utilized as a sign or in a striped arrangement to clearly provide a warning to a user. The various color responses provide multiple levels of alarm.

  17. Optical temperature indicator using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1996-01-01T23:59:59.000Z

    A reversible optical temperature indicator utilizes thermochromic semiconductors which vary in color in response to various temperature levels. The thermochromic material is enclosed in an enamel which provides protection and prevents breakdown at higher temperatures. Cadmium sulfide is the preferred semiconductor material. The indicator may be utilized as a sign or in a striped arrangement to clearly provide a warning to a user. The various color responses provide multiple levels of alarm.

  18. Effects of electrostatic discharge on three cryogenic temperature sensor models

    SciTech Connect (OSTI)

    Courts, S. Scott; Mott, Thomas B. [Lake Shore Cryotronics, 575 McCorkle Blvd., Westerville, OH 43082 (United States)

    2014-01-29T23:59:59.000Z

    Cryogenic temperature sensors are not usually thought of as electrostatic discharge (ESD) sensitive devices. However, the most common cryogenic thermometers in use today are thermally sensitive diodes or resistors - both electronic devices in their base form. As such, they are sensitive to ESD at some level above which either catastrophic or latent damage can occur. Instituting an ESD program for safe handling and installation of the sensor is costly and it is desirable to balance the risk of ESD damage against this cost. However, this risk cannot be evaluated without specific knowledge of the ESD vulnerability of the devices in question. This work examines three types of cryogenic temperature sensors for ESD sensitivity - silicon diodes, Cernox(trade mark, serif) resistors, and wire wound platinum resistors, all manufactured by Lake Shore Cryotronics, Inc. Testing was performed per TIA/EIA FOTP129 (Human Body Model). Damage was found to occur in the silicon diode sensors at discharge levels of 1,500 V. For Cernox(trade mark, serif) temperature sensors, damage was observed at 3,500 V. The platinum temperature sensors were not damaged by ESD exposure levels of 9,900 V. At the lower damage limit, both the silicon diode and the Cernox(trade mark, serif) temperature sensors showed relatively small calibration shifts of 1 to 3 K at room temperature. The diode sensors were stable with time and thermal cycling, but the long term stability of the Cernox(trade mark, serif) sensors was degraded. Catastrophic failure occurred at higher levels of ESD exposure.

  19. Temperature measurement method using temperature coefficient timing for resistive or capacitive sensors

    DOE Patents [OSTI]

    Britton, C.L. Jr.; Ericson, M.N.

    1999-01-19T23:59:59.000Z

    A method and apparatus for temperature measurement especially suited for low cost, low power, moderate accuracy implementation. It uses a sensor whose resistance varies in a known manner, either linearly or nonlinearly, with temperature, and produces a digital output which is proportional to the temperature of the sensor. The method is based on performing a zero-crossing time measurement of a step input signal that is double differentiated using two differentiators functioning as respective first and second time constants; one temperature stable, and the other varying with the sensor temperature. 5 figs.

  20. Temperature measurement method using temperature coefficient timing for resistive or capacitive sensors

    DOE Patents [OSTI]

    Britton, Jr., Charles L. (Alcoa, TN); Ericson, M. Nance (Knoxville, TN)

    1999-01-01T23:59:59.000Z

    A method and apparatus for temperature measurement especially suited for low cost, low power, moderate accuracy implementation. It uses a sensor whose resistance varies in a known manner, either linearly or nonlinearly, with temperature, and produces a digital output which is proportional to the temperature of the sensor. The method is based on performing a zero-crossing time measurement of a step input signal that is double differentiated using two differentiators functioning as respective first and second time constants; one temperature stable, and the other varying with the sensor temperature.

  1. Fibre-optic interferometric pressure sensor based on droplet-shaped PDMS elastomer

    E-Print Network [OSTI]

    Vlachos, Kyriakos G.

    Fibre-optic interferometric pressure sensor based on droplet-shaped PDMS elastomer C. Markos1 , K *gkakaran@eie.gr Keywords: white-light interferometer, fibre-optic pressure sensor, PDMS-based Fabry progress in fiber-optic extrinsic Fabry­Perot interferometric sensors ", Optical Fiber Technology, 23, p

  2. Simulation, implementation, and analysis of an optical fiber bundle distance sensor with

    E-Print Network [OSTI]

    Huang, Haiying

    Simulation, implementation, and analysis of an optical fiber bundle distance sensor with single Optical Society of America OCIS codes: 060.2370, 120.2830. 1. Introduction Optical fiber distance sensors. In general, optical fiber distance sensors can be divided into two categories: intensity

  3. Modeling and evaluating the performance of Brillouin distributed optical fiber sensors

    E-Print Network [OSTI]

    Dalang, Robert C.

    Modeling and evaluating the performance of Brillouin distributed optical fiber sensors Marcelo A analysis of the key factors impacting on the performance of Brillouin distributed optical fiber sensors of America OCIS codes: (060.2310) Fiber optics; (060.2370) Fiber optics sensors; (290.5900) Scattering

  4. Implementation of an integrated confocal sensor using planar optics S. Sinzinger, J. Jahns

    E-Print Network [OSTI]

    Jahns, Jürgen

    Implementation of an integrated confocal sensor using planar optics S. Sinzinger, J. Jahns We demonstrate an optical sensor head integrated in planar optics. The sensor is based on the confocal principle which is widely used in microscopy, sensing, and optical data storage. In order to achieve enhanced

  5. Interferometric fiber-optic bending/nano-displacement sensor using plastic dual-core fiber

    E-Print Network [OSTI]

    Skorobogatiy, Maksim

    Interferometric fiber-optic bending/nano-displacement sensor using plastic dual-core fiber H. Qu,1); published August 13, 2014 We demonstrate an interferometric fiber-optic bending/nano-displacement sensor for sensing the displacement. © 2014 Optical Society of America OCIS codes: (060.2370) Fiber optics sensors

  6. A two-mode fiber optic-bending sensor 

    E-Print Network [OSTI]

    Covington, Charles Eric

    1993-01-01T23:59:59.000Z

    relating the bending sensitivity to the shape of the profile's asymmetry are discussed. A temperature and strain compensated bending sensor for bending over arbitrary paths is demonstrated as an application of this technology. Some alternate two...

  7. Fiber optic laser-induced breakdown spectroscopy sensor for molten material analysis

    DOE Patents [OSTI]

    Zhang, Hansheng; Rai, Awadesh K.; Singh, Jagdish P.; Yueh, Fang-Yu

    2004-07-13T23:59:59.000Z

    A fiber optic laser-induced breakdown spectroscopy (LIBS) sensor, including a laser light source, a harmonic separator for directing the laser light, a dichroic mirror for reflecting the laser light, a coupling lens for coupling the laser light at an input of a multimode optical fiber, a connector for coupling the laser light from an output of the multimode optical fiber to an input of a high temperature holder, such as a holder made of stainless steel, and a detector portion for receiving emission signal and analyzing LIBS intensities. In one variation, the multimode optical fiber has silica core and silica cladding. The holder includes optical lenses for collimating and focusing the laser light in a molten alloy to produce a plasma, and for collecting and transmitting an emission signal to the multimode optical fiber.

  8. SINGLE SILVER NANOPARTICLES AS REAL-TIME OPTICAL SENSORS WITH ZEPTOMOLE SENSITIVITY

    E-Print Network [OSTI]

    Shull, Kenneth R.

    SINGLE SILVER NANOPARTICLES AS REAL-TIME OPTICAL SENSORS WITH ZEPTOMOLE SENSITIVITY Adam D. Mc-time sensor technologies. (A) A dark-field optical image of Ag nanoparticles immobilized on a glass substrate

  9. Calibration-free optical chemical sensors

    DOE Patents [OSTI]

    DeGrandpre, Michael D.

    2006-04-11T23:59:59.000Z

    An apparatus and method for taking absorbance-based chemical measurements are described. In a specific embodiment, an indicator-based pCO2 (partial pressure of CO2) sensor displays sensor-to-sensor reproducibility and measurement stability. These qualities are achieved by: 1) renewing the sensing solution, 2) allowing the sensing solution to reach equilibrium with the analyte, and 3) calculating the response from a ratio of the indicator solution absorbances which are determined relative to a blank solution. Careful solution preparation, wavelength calibration, and stray light rejection also contribute to this calibration-free system. Three pCO2 sensors were calibrated and each had response curves which were essentially identical within the uncertainty of the calibration. Long-term laboratory and field studies showed the response had no drift over extended periods (months). The theoretical response, determined from thermodynamic characterization of the indicator solution, also predicted the observed calibration-free performance.

  10. Electro-optic voltage sensor with beam splitting

    DOE Patents [OSTI]

    Woods, Gregory K. (Cornelius, OR); Renak, Todd W. (Idaho Falls, ID); Davidson, James R. (Idaho Falls, ID); Crawford, Thomas M. (Idaho Falls, ID)

    2002-01-01T23:59:59.000Z

    The invention is a miniature electro-optic voltage sensor system capable of accurate operation at high voltages without use of the dedicated voltage dividing hardware typically found in the prior art. The invention achieves voltage measurement without significant error contributions from neighboring conductors or environmental perturbations. The invention employs a transmitter, a sensor, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor. Within the sensor the beam undergoes the Pockels electro-optic effect. The electro-optic effect produces a modulation of the beam's polarization, which is in turn converted to a pair of independent conversely-amplitude-modulated signals, from which the voltage of the E-field is determined by the signal processor. The use of converse AM signals enables the signal processor to better distinguish signal from noise. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  11. Electro-optic voltage sensor with Multiple Beam Splitting

    DOE Patents [OSTI]

    Woods, Gregory K. (Cornelius, OR); Renak, Todd W. (Idaho Falls, ID); Crawford, Thomas M. (Idaho Falls, ID); Davidson, James R. (Idaho Falls, ID)

    2000-01-01T23:59:59.000Z

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages without use of the dedicated voltage dividing hardware. The invention achieves voltage measurement without significant error contributions from neighboring conductors or environmental perturbations. The invention employs a transmitter, a sensor, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor. Within the sensor the beam undergoes the Pockels electro-optic effect. The electro-optic effect produces a modulation of the beam's polarization, which is in turn converted to a pair of independent conversely-amplitude-modulated signals, from which the voltage of the E-field is determined by the signal processor. The use of converse AM signals enables the signal processor to better distinguish signal from noise. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  12. STRAIN MONITORING IN STIFFENED COMPOSITE PANELS USING EMBEDDED FIBRE OPTICAL AND STRAIN GAUGE SENSORS

    E-Print Network [OSTI]

    Boyer, Edmond

    (SHM) system based on Fibre Optic Bragg Grating (FOBG) sensors and standard resistance strain gauges for CFRP fuselage stiffened panels based on fibre optic Bragg grating sensors for the Green Regional. Among these approaches, methods based on optical [1]-[6] sensors are among the most rapidly developing

  13. Comparison of fingerprint quality measures using an optical and a capacitive sensor

    E-Print Network [OSTI]

    Autonoma de Madrid, Universidad

    Comparison of fingerprint quality measures using an optical and a capacitive sensor Fernando Alonso of Cagliari images are expected to be different for optical and capacitive sensors. For example, the effect measure computation. In our opinion, some measures could be suitable for the optical sensor

  14. Planar Integrated Free Space Optic Plasmonic Sensor Christopher A. Jones, Stefan F. Helfert and Jurgen Jahns

    E-Print Network [OSTI]

    Jahns, Jürgen

    Planar Integrated Free Space Optic Plasmonic Sensor Christopher A. Jones, Stefan F. Helfert and J sensor. This sensor could be easily connected to a conventional optical system. The orthogonal interfaces complex operations on the transmitted information. One simple way of achieving this on optical signals

  15. Ico-photonics-delphi2009.org Fibre-optic interferometric pressure sensor based on

    E-Print Network [OSTI]

    Vlachos, Kyriakos G.

    Ico-photonics-delphi2009.org Fibre-optic interferometric pressure sensor based on droplet pressure sensor, PDMS-based Fabry-Perot cavity A range of single-mode fibre-optic based on reflective Fabry­Perot interferometric sensors ", Optical Fiber Technology, 23, p.227- 237, 2006. [2] Florian Schneider , Jan Draheim

  16. Optical efficiency of image sensor pixels Peter B. Catrysse and Brian A. Wandell

    E-Print Network [OSTI]

    Wandell, Brian A.

    Optical efficiency of image sensor pixels Peter B. Catrysse and Brian A. Wandell Department sensor pixel by using a geometrical-optics phase-space approach. We compare the theoretical predictions, we show how to use these optical efficiency calculations to trade off image sensor pixel sensitivity

  17. Fig. 1. Teleoperated slave robot. Optical Torque Sensors for Local Impedance Control

    E-Print Network [OSTI]

    Tachi, Susumu

    Fig. 1. Teleoperated slave robot. Optical Torque Sensors for Local Impedance Control Realization_teterukov@ipc.i.u-tokyo.ac.jp We recently developed an optical torque sensor to replace expensive strain-gauge-based sensor on the anthropomorphic robot arm and realize local impedance control in individual joints. Keywords: Optical torque

  18. 6189-47, Session 10 Optical spatial filtering velocimetry sensor for real-time

    E-Print Network [OSTI]

    6189-47, Session 10 Optical spatial filtering velocimetry sensor for real-time in-plane vibration-contact, low-cost optical sensor for real time detection and active vibration control of mechanical devices sensitivity to any translational vibration. The calibration of the sensor is independent of the optical

  19. SYNTACTIC AND COMPOSITE FOAMS Whispering gallery mode-based micro-optical sensors

    E-Print Network [OSTI]

    Ötügen, Volkan

    SYNTACTIC AND COMPOSITE FOAMS Whispering gallery mode-based micro-optical sensors for structural used in materials include piezoelectric particles, acoustic emission sensors, and optical fibers. Each. Use of fiber-optic sensors is advantageous in composite materials because they can become an integral

  20. Fibre optic sensor for continuous health monitoring in CFRP composite materials

    E-Print Network [OSTI]

    Fibre optic sensor for continuous health monitoring in CFRP composite materials Laurent Rippert on this material. In this research study, fibre optic sensors will be proven to offer an alternative for the robust a quite simple microbend optical sensor contains information on the elastic energy released whenever

  1. Low-speed optic-flow sensor onboard an unmanned helicopter flying outside over fields*

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Low-speed optic-flow sensor onboard an unmanned helicopter flying outside over fields* Guillaume.Fabiani}@onera.fr weight or were not very well characterized, except for the optical mouse sensors [21], with which] in that of 2-D optic flow sensors). It therefore seemed to be worth testing the reliability of the present 1-D

  2. Optical fiber-based fluorescent viscosity sensor Mark A. Haidekker and Walter J. Akers

    E-Print Network [OSTI]

    Theodorakis, Emmanuel

    Optical fiber-based fluorescent viscosity sensor Mark A. Haidekker and Walter J. Akers Department to molecular rotors in solution. An optical fiber-based fluorescent vis- cosity sensor may be used in real, we sought to develop an optical fiber-based sensor that could re- port changes in fluid viscosity

  3. REQUIREMENTS TO ESTABLISH FIBRE-OPTIC SENSORS FOR MONITORING OF STRUCTURES

    E-Print Network [OSTI]

    Boyer, Edmond

    REQUIREMENTS TO ESTABLISH FIBRE-OPTIC SENSORS FOR MONITORING OF STRUCTURES Wolfgang Habel, Vivien-12205 Berlin wolfgang.habel@bam.de ABSTRACT Fibre-optic sensors need to be more established examples where fibre-optic sensors provide outstanding knowledge about the structure's behaviour

  4. Bipolar pulse coding for enhanced performance in Brillouin distributed optical fiber sensors

    E-Print Network [OSTI]

    Thévenaz, Jacques

    Bipolar pulse coding for enhanced performance in Brillouin distributed optical fiber sensors-sideband suppressed-carrier (SSB-SC) modulation in Brillouin optical time-domain analysis (BOTDA) sensors. The SSB conventional unipolar sequences. Keywords: Stimulated Brillouin scattering, distributed optical fiber sensor

  5. 123BLPCn272october/november 2008 Optical fiber strain sensors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    123BLPC·n°272·october/november 2008 Optical fiber strain sensors for use in civil engineering: State-of-the-art, industrial applications and outlook ABSTRACT Optical fiber sensors prove-of-the-art assessment of optical fiber strain sensor use in civil engineering, nearly 20 years after their initial

  6. Accurate Insertion Strategies Using Simple Optical Sensors Eric Paulos John Canny

    E-Print Network [OSTI]

    Paulos, Eric

    Accurate Insertion Strategies Using Simple Optical Sensors Eric Paulos John Canny paulos-calibrating peg-in-hole in- sertion strategy using several very simple, inexpensive, and accurate optical sensors describe a method for performing accurate in- sertion operations using simple optical sensors. A key

  7. Fiber optics sensor for sub-nanometric displacement and wide bandwidth systems

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Fiber optics sensor for sub-nanometric displacement and wide bandwidth systems L. Perret, L. Ruaux, B. Cagneau, Y. Alayli, Fiber optics sensor for sub-nanometric displacement and wide bandwidth systems, Sensors and Actuators A Abstract , 165, 189-193 (2011). In this paper, we report fiber optics

  8. USE OF DISTRIBUTED FIBER OPTIC SENSORS TO DETECT DAMAGE IN A Xavier Chapeleau

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    USE OF DISTRIBUTED FIBER OPTIC SENSORS TO DETECT DAMAGE IN A PAVEMENT Xavier Chapeleau 1 , Juliette strains and crack initiation. These first tests demonstrate that distributed fiber optic sensor based, by monitoring strain profiles in the bituminous layers. KEYWORDS: Distributed fiber optic sensor, asphalt

  9. Vision based navigation using novel optical sensors

    E-Print Network [OSTI]

    Wazni, Karim Patrick

    1999-01-01T23:59:59.000Z

    An optical position measurement system based on Position Sensing Diode technology is tested in its planar version. The system features active target intensity control and signal light modulation. Preliminary calibration procedures are researched...

  10. Vision based navigation using novel optical sensors 

    E-Print Network [OSTI]

    Wazni, Karim Patrick

    1999-01-01T23:59:59.000Z

    An optical position measurement system based on Position Sensing Diode technology is tested in its planar version. The system features active target intensity control and signal light modulation. Preliminary calibration procedures are researched...

  11. Fiber Optic Cryogenic Sensors for Superconducting Magnets and Superconducting Power Transmission lines at CERN

    E-Print Network [OSTI]

    Chiuchiolo, A; Cusano, A; Bajko, M; Perez, J C; Bajas, H; Giordano, M; Breglio, G; Palmieri, L

    2014-01-01T23:59:59.000Z

    The design, fabrication and tests of a new generation of superconducting magnets for the upgrade of the LHC require the support of an adequate, robust and reliable sensing technology. The use of Fiber Optic Sensors is becoming particularly challenging for applications in extreme harsh environments such as ultra-low temperatures, high electromagnetic fields and strong mechanical stresses offering perspectives for the development of technological innovations in several applied disciplines.

  12. Sandia Energy - Sensors & Optical Diagnostics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol Home Distribution GridDocumentsInstitute of AdvancedSecuritySensors &

  13. Impurity-doped optical shock, detonation and damage location sensor

    DOE Patents [OSTI]

    Weiss, J.D.

    1995-02-07T23:59:59.000Z

    A shock, detonation, and damage location sensor providing continuous fiber-optic means of measuring shock speed and damage location, and could be designed through proper cabling to have virtually any desired crush pressure. The sensor has one or a plurality of parallel multimode optical fibers, or a singlemode fiber core, surrounded by an elongated cladding, doped along their entire length with impurities to fluoresce in response to light at a different wavelength entering one end of the fiber(s). The length of a fiber would be continuously shorted as it is progressively destroyed by a shock wave traveling parallel to its axis. The resulting backscattered and shifted light would eventually enter a detector and be converted into a proportional electrical signals which would be evaluated to determine shock velocity and damage location. The corresponding reduction in output, because of the shortening of the optical fibers, is used as it is received to determine the velocity and position of the shock front as a function of time. As a damage location sensor the sensor fiber cracks along with the structure to which it is mounted. The size of the resulting drop in detector output is indicative of the location of the crack. 8 figs.

  14. Impurity-doped optical shock, detonation and damage location sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    1995-01-01T23:59:59.000Z

    A shock, detonation, and damage location sensor providing continuous fiber-optic means of measuring shock speed and damage location, and could be designed through proper cabling to have virtually any desired crush pressure. The sensor has one or a plurality of parallel multimode optical fibers, or a singlemode fiber core, surrounded by an elongated cladding, doped along their entire length with impurities to fluoresce in response to light at a different wavelength entering one end of the fiber(s). The length of a fiber would be continuously shorted as it is progressively destroyed by a shock wave traveling parallel to its axis. The resulting backscattered and shifted light would eventually enter a detector and be converted into a proportional electrical signals which would be evaluated to determine shock velocity and damage location. The corresponding reduction in output, because of the shortening of the optical fibers, is used as it is received to determine the velocity and position of the shock front as a function of time. As a damage location sensor the sensor fiber cracks along with the structure to which it is mounted. The size of the resulting drop in detector output is indicative of the location of the crack.

  15. OPTICAL FIBER SENSOR TECHNOLOGIES FOR EFFICIENT AND ECONOMICAL OIL RECOVERY

    SciTech Connect (OSTI)

    A. Wang; H. Xiao; R. May

    1999-10-29T23:59:59.000Z

    Efficient and complete recovery of petroleum reserves from existing oil wells has proven difficult due to a lack of robust instrumentation that can monitor processes in the downhole environment. Commercially available sensors for measurement of pressure, temperature, and fluid flow exhibit shortened lifetimes in the harsh downhole conditions, which are characterized by high pressures (up to 20 kpsi), temperatures up to 250 C, and exposure to chemically reactive fluids. Development of robust sensors that deliver continuous, real-time data on reservoir performance and petroleum flow pathways will facilitate application of advanced recovery technologies, including horizontal and multi-lateral wells. The main objective of the research program is to develop cost-effective, reliable fiber sensor instrumentation for real-time monitoring and /or control of various key parameters crucial to efficient and economical oil production. This report presents the detailed research work and technical progress from October 1, 1998 to September 30, 1999. The research performed over the first year of the program has followed the schedule as proposed, and solid research progress has been made in specification of the technical requirements, design and fabrication of the SCIIB sensor probes, development of the sensor systems, development of DSP-based signal processing techniques, and construction of the test systems. These technical achievements will significantly help to advance continued research on sensor tests and evaluation during the second year of the program.

  16. Temperature compensated and self-calibrated current sensor using reference magnetic field

    DOE Patents [OSTI]

    Yakymyshyn, Christopher Paul (Seminole, FL); Brubaker, Michael Allen (Loveland, CO); Yakymyshyn, Pamela Jane (Seminole, FL)

    2007-10-09T23:59:59.000Z

    A method is described to provide temperature compensation and self-calibration of a current sensor based on a plurality of magnetic field sensors positioned around a current carrying conductor. A reference magnetic field generated within the current sensor housing is detected by the magnetic field sensors and is used to correct variations in the output signal due to temperature variations and aging.

  17. Optical penetration sensor for pulsed laser welding

    DOE Patents [OSTI]

    Essien, Marcelino (Albuquerque, NM); Keicher, David M. (Albuquerque, NM); Schlienger, M. Eric (Albuquerque, NM); Jellison, James L. (Albuquerque, NM)

    2000-01-01T23:59:59.000Z

    An apparatus and method for determining the penetration of the weld pool created from pulsed laser welding and more particularly to an apparatus and method of utilizing an optical technique to monitor the weld vaporization plume velocity to determine the depth of penetration. A light source directs a beam through a vaporization plume above a weld pool, wherein the plume changes the intensity of the beam, allowing determination of the velocity of the plume. From the velocity of the plume, the depth of the weld is determined.

  18. Modeling a Prototype Optical Collision Avoidance Sensor For Unmanned Aerial Vehicles

    E-Print Network [OSTI]

    Hornsey, Richard

    Modeling a Prototype Optical Collision Avoidance Sensor For Unmanned Aerial Vehicles Cyrus Minwalla) are essential in controlled airspace under visual flight rules (VFR). A prototype optical sensor accomplishes and evaluation of the prototype sensor are presented here, as are preliminary measurements to clarify the roles

  19. Performance characterization of an internsity-modulated fiber optic displacement sensor

    SciTech Connect (OSTI)

    Moro, Erik Allan [Los Alamos National Laboratory; Todd, Michael D [Los Alamos National Laboratory; Puckett, Santhony D [Los Alamos National Laboratory

    2010-09-30T23:59:59.000Z

    A testbed simulating an intensity-modulated fiber optic displacement sensor is experimentally characterized, and the implications regarding sensor design are discussed. Of interest are the intensity distribution of the transmitted optical signal and the relationships between sensor architecture and performance. Particularly, an intensity-modulated sensor's sensitivity, linearity, displacement range, and resolution are functions of the relative positioning of its transmitting and receiving fibers. In this paper, sensor architectures with various combinations of these performance metrics are discussed. A sensor capable of micrometer resolution is reported, and it is concluded that this work could lead to an improved methodology for sensor design.

  20. Application of fiber optic temperature and strain sensing technology to gas hydrates

    SciTech Connect (OSTI)

    Ulrich, Shannon M [ORNL; Madden, Megan Elwood [ORNL; Rawn, Claudia J [ORNL; Szymcek, Phillip [ORNL; Phelps, Tommy Joe [ORNL

    2008-01-01T23:59:59.000Z

    Gas hydrates may have a significant influence on global carbon cycles due to their large carbon storage capacity in the form of greenhouse gases and their sensitivity to small perturbations in local conditions. Characterizing existing gas hydrate and the formation of new hydrate within sediment systems and their response to small changes in temperature and pressure is imperative to understanding how this dynamic system functions. Fiber optic sensing technology offers a way to measure precisely temperature and strain in harsh environments such as the seafloor. Recent large-scale experiments using Oak Ridge National Laboratory's Seafloor Process Simulator were designed to evaluate the potential of fiber optic sensors to study the formation and dissociation of gas hydrates in 4-D within natural sediments. Results indicate that the fiber optic sensors are so sensitive to experimental perturbations (e.g. refrigeration cycles) that small changes due to hydrate formation or dissociation can be overshadowed.

  1. Design and Verification of an Optical System to Interrogate Dermally-implanted Microparticle Sensors 

    E-Print Network [OSTI]

    Long, Ruiqi

    2012-07-16T23:59:59.000Z

    patient adherence to the recommended self-monitoring frequency, non-invasive/ minimally invasive glucose testing approaches are needed. Luminescent microparticle sensor is an attractive solution. For these sensors to be deployed in vivo, a matched optical...

  2. Focal-Plane Image and Beam Quality Sensors for Adaptive Optics

    E-Print Network [OSTI]

    Cauwenberghs, Gert

    Focal-Plane Image and Beam Quality Sensors for Adaptive Optics Marc CohenÝ, Gert Cauwenberghs]. Therefore a critical component in the stochastic control system for adaptive optics is the metric sensor Engineering 3400 North Charles Street, Baltimore, MD 21211 ÞArmy Research Laboratory, Intelligent Optics

  3. Miniaturized optical sensor for cursor control Michael Linde Jakobsen, Henning Larsen, Finn Pedersen, Henrik Pedersen,

    E-Print Network [OSTI]

    20 Miniaturized optical sensor for cursor control Michael Linde Jakobsen, Henning Larsen, Finn and Jørgen Korsgaard OPDI Technologies, Denmark A miniaturized optical displacement sensor that can information of the movement but also to optically establish a dynamic high-pass filtering, thus removing

  4. Radiometric Correctionradiometric correction Radiometric correction is important to ensure that terrestrial variables retrieved from optical satellite sensor

    E-Print Network [OSTI]

    Coburn, Craig

    that terrestrial variables retrieved from optical satellite sensor systems are calibrated to a common physical interactions. Radiometric corrections of optical sensor data consider sensor radiometric calibration, surface reflectance propagated through the atmosphere to the satellite sensor. Given that the optical properties

  5. > REPLACE THIS LINE WITH YOUR PAPER IDENTIFICATION NUMBER (DOUBLE-CLICK HERE TO EDIT) optical fiber sensors (DOFS) have

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    --Distributed optical fiber sensors (DOFS) have gained an increasingly prominent role in structural-health monitoring of electronic equipment at the site. Complementary to these sensors, distributed optical fiber sensors (DOFS optical fiber, and a large number of sensors can be multiplexed to enhance their economic viability. Due

  6. NONLINEAR EFFECTS OF A MODAL DOMAIN OPTICAL FIBER SENSOR IN A VIBRATION SUPPRESSION CONTROL LOOP FOR A FLEXIBLE

    E-Print Network [OSTI]

    Lindner, Douglas K.

    NONLINEAR EFFECTS OF A MODAL DOMAIN OPTICAL FIBER SENSOR IN A VIBRATION SUPPRESSION CONTROL LOOP Recently, a modal domain optical fiber sensor has been demonstrated as a sensor in a control system the region of linear operation in terms of the optical fiber sensor parameters. #12;2 1. INTRODUCTION

  7. JW2A.3.pdf Imaging and Applied Optics Technical Digest 2012 OSA Optical Microfiber Sensors for the Detection of Current

    E-Print Network [OSTI]

    JW2A.3.pdf Imaging and Applied Optics Technical Digest © 2012 OSA Optical Microfiber Sensors microfibers for current sensing are discussed. OCIS codes: (060.2370) Fiber optics sensors; (230.2240) Faraday effect. 1. Introduction Current sensors exploiting the Faraday Effect in optical fibers [1] have

  8. An image sensor with on-die diffractive optics in 0.18m bulk Christopher Thomas, Richard Hornsey

    E-Print Network [OSTI]

    Hornsey, Richard

    An image sensor with on-die diffractive optics in 0.18µm bulk CMOS Christopher Thomas, Richard of reducing package size for imaging and non-imaging optical sensors. While systems incorporating on image sensors, microlenses, diffraction gratings, micro-optics, diffractive optics 1. INTRODUCTION

  9. Fiber optic sensor: Feedback control design and implementation

    SciTech Connect (OSTI)

    Tung, D.; Bertram, L.; Hillaire, R.; Anderson, S.; Leonard, S.; Marburger, S.

    1997-07-01T23:59:59.000Z

    Digital feedback control of Gas Tungsten Arc Welding (GTAW) has been demonstrated on a tube sample of stainless steel and titanium alloy. A fiber optic sensor returns a signal proportional to backside radiance from the workpiece; that signal is used by the controller to compute a compensation weld current. The controller executes 10 times a second on an Intel 486 chip. For travel speeds of 3 to 6 inches per minute and thicknesses between 0.025 and 0.10 inches, constant backside bead width was maintained within 0.02 inches, from startup to tie-in.

  10. Temperature compensated and self-calibrated current sensor using reference current

    DOE Patents [OSTI]

    Yakymyshyn, Christopher Paul (Seminole, FL); Brubaker, Michael Allen (Loveland, CO); Yakymyshyn, Pamela Jane (Seminole, FL)

    2008-01-22T23:59:59.000Z

    A method is described to provide temperature compensation and self-calibration of a current sensor based on a plurality of magnetic field sensors positioned around a current carrying conductor. A reference electrical current carried by a conductor positioned within the sensing window of the current sensor is used to correct variations in the output signal due to temperature variations and aging.

  11. Room-temperature mid-infrared laser sensor for trace gas detection

    E-Print Network [OSTI]

    , and pipeline leak detection. Applications such as landfill emissions monitoring require measurements of gasRoom-temperature mid-infrared laser sensor for trace gas detection Thomas To¨ pfer, Konstantin P of a compact, portable, room-temperature mid-infrared gas sensor is reported. The sensor is based on continuous

  12. A Single SQUID Multiplexer for Arrays of Low Temperature Sensors Jongsoo Yoona)

    E-Print Network [OSTI]

    Richards, Paul L.

    1 A Single SQUID Multiplexer for Arrays of Low Temperature Sensors Jongsoo Yoona) , John Clarkea and experimental evaluation of a superconducting quantum interference device (SQUID) mul- tiplexer for an array of low-temperature sensors. Each sensor is inductively coupled to a superconducting summing loop which

  13. Downhole geothermal well sensors comprising a hydrogen-resistant optical fiber

    DOE Patents [OSTI]

    Weiss, Jonathan D.

    2005-02-08T23:59:59.000Z

    A new class of optical fiber based thermal sensors has been invented. The new sensors comprise hydrogen-resistant optical fibers which are able to withstand a hot, hydrogen-containing environment as is often found in the downhole well environment.

  14. Fabrication and characterization of coaxial scanning near-field optical microscopy cantilever sensors

    E-Print Network [OSTI]

    Aeschlimann, Martin

    -electromechanical (MEMS) fabrication technology in or- der to produce sensors with reproducible optical and mechanicalFabrication and characterization of coaxial scanning near-field optical microscopy cantilever sensors M. Salomo *, D. Bayer, B.R. Schaaf, M. Aeschlimann, E. Oesterschulze * Department of Physics

  15. Lakes as sensors in the landscape: Optical metrics as scalable sentinel responses to climate change

    E-Print Network [OSTI]

    Williamson, Craig E.

    Lakes as sensors in the landscape: Optical metrics as scalable sentinel responses to climate change, Edgewater, Maryland Abstract As the lowest point in the surrounding landscape, lakes act as sensors. Here a novel suite of climate forcing optical indices (CFOI) from lakes across North America is found

  16. Evaluating a genetically encoded optical sensor of neural activity using electrophysiology in intact adult fruit flies

    E-Print Network [OSTI]

    Laurent, Gilles

    Evaluating a genetically encoded optical sensor of neural activity using electrophysiology of America Rafael Yuste, Columbia University, New York City, USA Genetically encoded optical indicators hold. However, the interpretation of images of brain activity produced using such sensors is not straightforward

  17. A planar lightwave circuit based micro interrogator and its applications to the interrogation of multiplexed optical fiber Bragg grating sensors

    E-Print Network [OSTI]

    Yao, Jianping

    of multiplexed optical fiber Bragg grating sensors Gaozhi Xiao a,*, Nezih Mrad b , Honglei Guo c , Zhiyi Zhang Accepted 20 August 2008 Keywords: Micro interrogator Fiber Bragg grating sensors a b s t r a c t Optical have developed a micro optical sensor interrogator using a monolithically integrated planar lightwave

  18. Processing of transient signals from damage in CFRP composite materials monitored with embedded intensity-modulated fiber optic sensors

    E-Print Network [OSTI]

    intensity-modulated fiber optic sensors M. Weversa , L. Ripperta , J.-M. Papyb , S. Van Huffelb a Department-modulated fiber optic sensors, whose working principle is based on the microbending concept, are used to monitor. In this approach fibre optic sensors may offer an alternative for the robust piezoelectric transducers used

  19. NRA-00-OES-08 A one-year pilot study for the inclusion of active optical sensors into PALACE

    E-Print Network [OSTI]

    Boss, Emmanuel S.

    NRA-00-OES-08 1 A one-year pilot study for the inclusion of active optical sensors into PALACE, newly-developed solid-state, active optical sensors that measure chlorophyll a fluorescence in the ocean. The incorporation of this new generation of optical sensors on a even a subset of the ARGO floats

  20. Device for self-verifying temperature measurement and control

    DOE Patents [OSTI]

    Watkins, Arthur D.; Cannon, Collins P.; Tolle, Charles R.

    2004-08-03T23:59:59.000Z

    A measuring instrument includes a first temperature sensor, a second temperature sensor and circuitry. The first and second temperature sensors each generate a signal indicative of the temperature of a medium being detected. The circuitry is configured to activate verification of temperature being sensed with the first sensor. According to one construction, the first temperature sensor comprises at least one thermocouple temperature sensor and the second temperature sensor comprises an optical temperature sensor, each sensor measuring temperature over the same range of temperature, but using a different physical phenomena. Also according to one construction, the circuitry comprises a computer configured to detect failure of one of the thermocouples by comparing temperature of the optical temperature sensor with each of the thermocouple temperature sensors. Even further, an output control signal is generated via a fuzzy inference machine and control apparatus.

  1. IEEE SENSORS JOURNAL, VOL. 10, NO. 6, JUNE 2010 1075 Active Temperature Programming for

    E-Print Network [OSTI]

    Gutierrez-Osuna, Ricardo

    temperature of metal-oxide (MOX) chemical sensors gives rise to gas-specific signatures that provide a wealth. Index Terms--Active sensing, hidden Markov models, metal- oxide (MOX) sensors, partially observable Markov decision pro- cesses (POMDP). I. INTRODUCTION METAL-OXIDE (MOX) gas sensors are robust, inexpen

  2. Development of a 1 x N Fiber Optic Sensor Array for Carbon Sequestration Site Monitoring

    SciTech Connect (OSTI)

    Repasky, Kevin

    2013-09-30T23:59:59.000Z

    A fiber sensor array for sub-surface CO{sub 2} concentrations measurements was developed for monitoring geologic carbon sequestration sites. The fiber sensor array uses a single temperature tunable distributed feedback (DFB) laser operating with a nominal wavelength of 2.004 􀁐m. Light from this DFB laser is direct to one of the 4 probes via an in-line 1 x 4 fiber optic switch. Each of the 4 probes are buried and allow the sub-surface CO{sub 2} to enter the probe through Millipore filters that allow the soil gas to enter the probe but keeps out the soil and water. Light from the DFB laser interacts with the CO{sub 2} before it is directed back through the in-line fiber optic switch. The DFB laser is tuned across two CO{sub 2} absorption features where a transmission measurement is made allowing the CO{sub 2} concentration to be retrieved. The fiber optic switch then directs the light to the next probe where this process is repeated allowing sub-surface CO{sub 2} concentration measurements at each of the probes to be made as a function of time. The fiber sensor array was deployed for fifty-eight days beginning June 19, 2012 at the Zero Emission Research Technology (ZERT) field site where sub-surface CO{sub 2} concentrations were monitored. Background measurements indicate the fiber sensor array can monitor background levels as low as 1,000 parts per million (ppm). A thirty four day sub-surface release of 0.15 tones CO{sub 2}/day began on July 10, 2012. The elevated subsurface CO{sub 2} concentration was easily detected by each of the four probes with values ranging to over 60,000 ppm, a factor of greater than 6 higher than background measurements. The fiber sensor array was also deploy at the Big Sky Carbon Sequestration Partnership (BSCSP) site in north-central Montana between July 9th and August 7th, 2013 where background measurements were made in a remote sequestration site with minimal infrastructure. The project provided opportunities for two graduate students to participate in research directly related to geologic carbon sequestration. Furthermore, commercialization of the technology developed is being pursued with five different companies via the Department of energy SBIR/STTR program

  3. Cloud optical and microphysical properties derived from ground-based and satellite sensors over

    E-Print Network [OSTI]

    Li, Zhanqing

    Cloud optical and microphysical properties derived from ground-based and satellite sensors over of cloud optical and microphysical properties were made at Taihu, a highly polluted site in the central Yangtze Delta region, during a research campaign from May 2008 to December 2009. Cloud optical depth (COD

  4. 300°C Capable Electronics Platform and Temperature Sensor System For Enhanced Geothermal Systems

    Broader source: Energy.gov [DOE]

    Project objectives: Enable geothermal wellbore monitoring through the development of SiC based electronics and ceramic packaging capable of sustained operation at temperatures up to 300?C and 10 km depth. Demonstrate the technology with a temperature sensor system.

  5. Optics-less smart sensors and a possible mechanism of cutaneous vision in nature

    E-Print Network [OSTI]

    Leonid Yaroslavsky; Chad Goerzen; Stanislav Umansky; H. John Caulfield

    2008-08-08T23:59:59.000Z

    Optics-less cutaneous (skin) vision is not rare among living organisms, though its mechanisms and capabilities have not been thoroughly investigated. This paper demonstrates, using methods from statistical parameter estimation theory and numerical simulations, that an array of bare sensors with a natural cosine-law angular sensitivity arranged on a flat or curved surface has the ability to perform imaging tasks without any optics at all. The working principle of this type of optics-less sensor and the model developed here for determining sensor performance may be used to shed light upon possible mechanisms and capabilities of cutaneous vision in nature.

  6. Low-Voltage CMOS Temperature Sensor Design Using Schottky Diode-Based References

    E-Print Network [OSTI]

    Baker, R. Jacob

    have been used for many years in systems such as air conditioners, heating systems, and automotive-delta temperature sensor using Schottky diode-based current references as a replacement for the traditional PN diode as a replacement for the tradition PN junction diode in a temperature sensor. It also explores

  7. DESIGN OF TEMPERATURE SENSOR ARRAY IN SMART ELECTRIC GRID BASED ON SAW RESONATORS

    E-Print Network [OSTI]

    Wang, Ji

    387 DESIGN OF TEMPERATURE SENSOR ARRAY IN SMART ELECTRIC GRID BASED ON SAW RESONATORS Yu-lin HAN1 than 1, and the sensitivity of sensor is up to 4 KHz/. Keywords: SAW; Smart electric grid; Temperature the stability of smart electric grids. Equipment and parts of the power system in urgent need of online

  8. AOI [3] High-Temperature Nano-Derived Micro-H2 and - H2S Sensors

    SciTech Connect (OSTI)

    Perepezko, John; Lu-Steffes, Otto

    2014-08-31T23:59:59.000Z

    The emissions from coal-fired power plants remain a significant concern for air quality. This environmental challenge must be overcome by controlling the emission of sulfur dioxide (SO2) and hydrogen sulfide (H2S) throughout the entire coal combustion process. One of the processes which could specifically benefit from robust, low cost, and high temperature compatible gas sensors is the coal gasification process which converts coal and/or biomass into syngas. Hydrogen (H2), carbon monoxide (CO) and sulfur compounds make up 33%, 43% and 2% of syngas, respectively. Therefore, development of a high temperature (>500°C) chemical sensor for in-situ monitoring of H2, H2S and SO2 levels during coal gasification is strongly desired. The selective detection of SO2/H2S in the presence of H2, is a formidable task for a sensor designer. In order to ensure effective operation of these chemical sensors, the sensor system must inexpensively function within harsh temperature and chemical environment. Currently available sensing approaches, which are based on gas chromatography, electrochemistry, and IR-spectroscopy, do not satisfy the required cost and performance targets. This work focused on the development microsensors that can be applied to this application. In order to develop the high- temperature compatible microsensor, this work addressed various issues related to sensor stability, selectivity, and miniaturization. In the research project entitled “High-Temperature Nano-Derived Micro-H2 and -H2S Sensors”, the team worked to develop micro-scale, chemical sensors and sensor arrays composed of nano-derived, metal-oxide composite materials to detect gases like H2, SO2, and H2S within high-temperature environments (>500?C). The research was completed in collaboration with NexTech Materials, Ltd. (Lewis Center, Ohio). NexTech assisted in the testing of the sensors in syngas with contaminate levels of H2S. The idea of including nanomaterials as the sensing material within resistive-type chemical sensor platforms was to increase the sensitivity (as shown for room temperature applications). Unfortunately, nanomaterials are not stable at high temperatures due to sintering and coarsening processes that are driven by their high surface to volume ratio. Therefore, new hydrogen and sulfur selective nanomaterial systems with high selectivity and stability properties in the proposed harsh environment were investigated. Different nano-morphologies of zirconate, molybdate, and tungstate compounds were investigated. The fabrication of the microsensors consisted of the deposition of the selective nanomaterial systems over metal based interconnects on an inert substrate. This work utilized the chemi-resistive (resistive- type) microsensor architecture where the chemically and structurally stable, high temperature compatible electrodes were sputtered onto a ceramic substrate. The nanomaterial sensing systems were deposited over the electrodes using a lost mold method patterned by conventional optical lithography. The microsensor configuration with optimized nanomaterial system was tested and compared to a millimeter-size sensor e outcomes of this research will contribute to the economical application of sensor arrays for simultaneous sensing of H2, H2S, and SO2.

  9. DEVELOPMENT OF NOVEL CERAMIC NANOFILM-FIBER INTEGRATED OPTICAL SENSORS FOR RAPID DETECTION OF COAL DERIVED SYNTHESIS GAS

    SciTech Connect (OSTI)

    Junhang Dong; Hai Xiao; Xiling Tang; Hongmin Jiang; Kurtis Remmel; Amardeep Kaur

    2012-09-30T23:59:59.000Z

    The overall goal of this project is to conduct fundamental studies on advanced ceramic materials and fiber optic devices for developing new types of high temperature (>500{degree}C) fiber optic chemical sensors (FOCS) for monitoring fossil (mainly coal) and biomass derived gases in power plants. The primary technical objective is to investigate and demonstrate the nanocrystalline doped-ceramic thin film enabled FOCS that possess desired stability, sensitivity and selectivity for in-situ, rapid gas detection in the syngas streams from gasification and combustion flue gases. This report summarizes research works of two integrated parts: (1) development of metal oxide solid thin films as sensing materials for detection and measurement of important gas components relevant to the coal- and biomass-derived syngas and combustion gas streams at high temperatures; and (2) development of fiber optic devices that are potentially useful for constructing FOCS in combination with the solid oxide thin films identified in this program.

  10. The application of fiber optic sensors to the monitoring of roller element bearing systems 

    E-Print Network [OSTI]

    Juarez, Juan Carlos

    2002-01-01T23:59:59.000Z

    A rotating machinery test rig was instrumented with fiber optic Fabry-Perot Interferometer (FFPI) strain sensors for condition monitoring of rolling element bearings. Wavelength division multiplexing (WDM) was utilized to simultaneously monitor...

  11. Adaptive optics wavefront sensors based on photon-counting detector arrays

    E-Print Network [OSTI]

    Aull, Brian F.

    For adaptive optics systems, there is a growing demand for wavefront sensors that operate at higher frame rates and with more pixels while maintaining low readout noise. Lincoln Laboratory has been investigating Geiger-mode ...

  12. An experimental investigation of the sensitivity of a buried fiber optic intrusion sensor 

    E-Print Network [OSTI]

    Kuppuswamy, Harini

    2006-04-12T23:59:59.000Z

    A distributed fiber optic sensor with the ability of detecting and locating intruders on foot and vehicles over long perimeters (>10 km) was studied. The response of the sensor to people walking over or near it and to vehicles driving nearby...

  13. The application of fiber optic sensors to the monitoring of roller element bearing systems

    E-Print Network [OSTI]

    Juarez, Juan Carlos

    2002-01-01T23:59:59.000Z

    THE APPLICATION OF FIBER OPTIC SENSORS TO THE MONITORING OF ROLLER ELEMENT BEARING SYSTEMS A Thesis by JUAN CARLOS JUAREZ Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 2002 Major Subject: Electrical Engineering THE APPLICATION OF FIBER OPTIC SENSORS TO THE MONITORING OF ROLLER ELEMENT BEARING SVSTEMS A Thesis by . IIJAN CARLOS JUAREZ Submitted to Texas A&M University...

  14. Multipoint Pressure and Temperature Sensing Fiber Optic Cable for Monitoring CO2 Sequestration

    SciTech Connect (OSTI)

    Challener, William

    2014-12-31T23:59:59.000Z

    This report describes the work completed on contract DE-FE0010116. The goal of this two year project was to develop and demonstrate in the laboratory a highly accurate multi-point pressure measurement fiber optic cable based on MEMS pressure sensors suitable for downhole deployment in a CO2 sequestration well. The sensor interrogator was also to be demonstrated in a remote monitoring system and environmental testing was to be completed to indicate its downhole survivability over a lengthy period of time (e.g., 20 years). An interrogator system based on a pulsed laser excitation was shown to be capable of multiple (potentially 100+) simultaneous sensor measurements. Two sensors packages were completed and spliced in a cable onto the same fiber and measured. One sensor package was subsequently measured at high temperatures and pressures in supercritical CO2, while the other package was measured prior and after being subjected to high torque stresses to mimic downhole deployment. The environmental and stress tests indicated areas in which the package design should be further improved.

  15. EVALUATION OF AIRBORNE AND SATELLITE ELECTRO-OPTICAL SENSORS PERFORMANCES BY USE OF HIGH-ALTITUDE CLOUDS OCCURRENCE

    E-Print Network [OSTI]

    EVALUATION OF AIRBORNE AND SATELLITE ELECTRO-OPTICAL SENSORS PERFORMANCES BY USE OF HIGH The impact of high-altitude clouds along an electro- optical sensor line of sight has been studied, F-91761 Palaiseau, France, email : karine.caillault@onera.fr KEYWORDS: sensor performance

  16. A 16 mm3 autonomous solar-powered sensor node with bi-directional optical communication for distributed sensor net-

    E-Print Network [OSTI]

    Kahn, Joseph M.

    Abstract A 16 mm3 autonomous solar-powered sensor node with bi- directional optical communication, a 2.6 mm2 SOI solar cell array, and a micromachined four-quadrant corner-cube retroreflector (CCR- idly deployed by unmanned aerial vehicles (UAV), tracking the movements of birds, small animals

  17. Device and method for self-verifying temperature measurement and control

    DOE Patents [OSTI]

    Watkins, Arthur D. (Idaho Falls, ID); Cannon, Collins P. (Kearney, MO); Tolle, Charles R. (Idaho Falls, ID)

    2002-10-29T23:59:59.000Z

    A measuring instrument includes a first temperature sensor, a second temperature sensor and circuitry. The first and second temperature sensors each generate a signal indicative of the temperature of a medium being detected. The circuitry is configured to activate verification of temperature being sensed with the first sensor. According to one construction, the first temperature sensor comprises at least one thermocouple temperature sensor and the second temperature sensor comprises an optical temperature sensor, each sensor measuring temperature over the same range of temperature, but using a different physical phenomena. Also according to one construction, the circuitry comprises a computer configured to detect failure of one of the thermocouples by comparing temperature of the optical temperature sensor with each of the thermocouple temperature sensors. Even further, an output control signal is generated via a fuzzy inference machine and control apparatus.

  18. Fiber-optic sensor for detection of hydrogen peroxide in PEM fuel cells Juan F. Botero-Cadavid

    E-Print Network [OSTI]

    Victoria, University of

    Fiber-optic sensor for detection of hydrogen peroxide in PEM fuel cells by Juan F. Botero of an optical fiber and its small size (125 µm diameter), make the sensors here developed an ideal solution, by photocopy or other means, without the permission of the author. #12;ii Supervisory Committee Fiber-optic

  19. Structural and environmental monitoring of tracker and vertex systems using Fiber Optic Sensors

    E-Print Network [OSTI]

    Moya, David

    2012-01-01T23:59:59.000Z

    Fibre optic sensors (FOS) are an established technique for environmental and deformation monitoring in several areas like civil engineering, aerospace, and energy. Their immunity to electromagnetic and magnetic fields and nuclear environments, its small size, multiplexing capability and the possibility to be embedded make them an attractive technology for the structural and environmental monitoring of collider particle physics experiments. Between all the possible Fibre Optic sensors FBGs (Fiber Bragg Grating) seems to be the best solution for HEP applications. The first step was to characterize FBG sensors for it use in High Energy Physics environment. During last two years we have checked the resistance of the Fibre Bragg Grating sensors to radiation. Two irradiation campaigns with protons have been done at CNA (Centro Nacional de Aceleradores). In the near future these sensors are being planned to be used in detectors (the closest one Belle II.). Several work on integration issues in Belle II PXD-SVD, and ...

  20. ROOM TEMPERATURE STRENGTH DEGRADATION OF OPTICAL FIBERS

    E-Print Network [OSTI]

    Matthewson, M. John

    temperatures. 6 :4 Aging Time (s) Fig. 2. Residual strength of fiber B after aging in deionized water. Aging Time (s) Fig. 4. Data of Griffioen3 for residual strength (strain to failure) of fiber aged in water. 1) Fig. 1 . Residual strength of fiber A after aging in distilled water. io 10 i0 106 io 108 1.0 0.9 0 (0

  1. 1250 IEEE SENSORS JOURNAL VOL. 6, NO. 5, OCTOBER 2006 Room-Temperature Hydrogen Sensitivity

    E-Print Network [OSTI]

    Moritz, Werner

    , the dissociation of hydrogen molecules at the Pd gate electrode, diffusion of the atoms, and formation of a dipole and the mechanism of hydrogen detection at the Pd/oxide interface are summarized in [2]. For this sensor type in the semiconductor. The Pd/SiO2/Si-based sensor was used for hydrogen detection at room temperature, but the behavior

  2. Model Based Sensor System for Temperature Measurement in R744 Air Conditioning Systems

    E-Print Network [OSTI]

    Reitz, Sven; Schneider, Peter

    2008-01-01T23:59:59.000Z

    The goal is the development of a novel principle for the temperature acquisition of refrigerants in CO2 air conditioning systems. The new approach is based on measuring the temperature inside a pressure sensor, which is also needed in the system. On the basis of simulative investigations of different mounting conditions functional relations between measured and medium temperature will be derived.

  3. Langasite SAW temperature and oxygen multi-sensor P. Zheng,1,2

    E-Print Network [OSTI]

    Greve, David.W.

    such as monitoring the exhaust of oxy-fuel combustion systems. In this paper we report on the observed temperature sensors for the control of oxy-fuel combustion systems. In such combustors it is possible to achieve

  4. Micro optical fiber light source and sensor and method of fabrication thereof

    DOE Patents [OSTI]

    Kopelman, Raoul (Ann Arbor, MI); Tan, Weihong (Ames, IA); Shi, Zhong-You (Ann Arbor, MI)

    1997-01-01T23:59:59.000Z

    This invention relates generally to the development of and a method of fabricating a fiber optic micro-light source and sensor (50). An optical fiber micro-light source (50) is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors (22) in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material (60). This process allows significant control of the size of the micro light source (50). Furthermore, photo-chemically attaching an optically active material (60) enables the implementation of the micro-light source in a variety of sensor applications.

  5. Micro optical fiber light source and sensor and method of fabrication thereof

    DOE Patents [OSTI]

    Kopelman, R.; Tan, W.; Shi, Z.Y.

    1997-05-06T23:59:59.000Z

    This invention relates generally to the development of and a method of fabricating a fiber optic micro-light source and sensor. An optical fiber micro-light source is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material. This process allows significant control of the size of the micro light source. Furthermore, photo-chemically attaching an optically active material enables the implementation of the micro-light source in a variety of sensor applications. 10 figs.

  6. Optical position sensor for determining the interface between a clear and an opaque fluid

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    2006-05-23T23:59:59.000Z

    An inexpensive, optical position sensor for measuring a position or length, x, along a one-dimensional curvilinear, coordinate system. The sensor can be used, for example, to determine the position of an interface between a clear and an opaque fluid (such as crude oil and water). In one embodiment, the sensor utilizes the principle of dual-fluorescence, where a primary fiber emits primary fluorescent light and a parallel secondary fiber collects a portion of the primary fluorescent light that is not blocked by the opaque fluid. This, in turn, excites secondary fluorescence in the secondary fiber at a longer wavelength. A light detector measures the intensity of secondary fluorescence emitted from an end of the secondary fiber, which is used to calculate the unknown position or length, x. Side-emitting fibers can be used in place of, or in addition to, fluorescent fibers. The all-optical sensor is attractive for applications involving flammable liquids.

  7. ELEVATED TEMPERATURE SENSORS FOR ON-LINE CRITICAL EQUIPMENT HEALTH MONITORING

    SciTech Connect (OSTI)

    James Sebastian

    2005-03-01T23:59:59.000Z

    The objective of this research program is to improve high temperature piezoelectric aluminum nitride (AlN) sensor technology to make it useful for instrumentation and health monitoring of current and future electrical power generation equipment. The program will extend the temperature range of the sensor from approximately 700 C to above 1000 C, and ultrasonic coupling to objects at these temperatures will be investigated and tailored for use with the sensor. The chemical vapor deposition (CVD) AlN deposition process was successfully transferred from film production on tungsten carbide substrates to titanium alloy and silicon carbide (SiC) substrates in the first year of the program, and additional substrates were evaluated. In the second year of the program, additional substrate research was performed with the goal of improving the performance of using SiC substrates. While greatly improved bandwidth was achieved, sensor survival at elevated temperature remains problematic. The elevated temperature coupling work continued with significant experimentation. Molten glasses were found to work within a limited temperature range, but metal foils applied with heat and pressure were found to have superior performance overall. The final year of the program will be dedicated to making further advances in AlN/ substrate behavior, and the design and implementation of a sensor demonstration experiment at very high temperature in a simulated industrial application.

  8. Elevated Temperature Sensors for On-Line Critical Equipment Health Monitoring

    SciTech Connect (OSTI)

    James Sebastian

    2006-03-31T23:59:59.000Z

    The objective of the program was to improve high temperature piezoelectric aluminum nitride (AlN) sensor technology to make it useful for instrumentation and health monitoring of current and future electrical power generation equipment. Improvements were aimed primarily at extending the useful temperature range of the sensor from approximately 700 C to above 1000 C, and investigating ultrasonic coupling to objects at these temperatures and tailoring high temperature coupling for use with the sensor. During the project, the chemical vapor deposition (CVD) AlN deposition process was successfully transferred from film production on tungsten carbide substrates to titanium alloy and silicon carbide (SiC) substrates. Film adhesion under thermal cycling was found to be poor, and additional substrate materials and surface preparations were evaluated. A new, porous SiC substrate improved the performance but not to the point of making the films useful for sensors. Near the end of the program, a new family of high temperature piezoelectric materials came to the attention of the program. Samples of langasite, the most promising member of this family, were obtained and experimental data showed promise for use up to the 1000 C target temperature. In parallel, research successfully determined that metal foil under moderate pressure provided a practical method of coupling ultrasound at high temperature. A conceptual sensor was designed based upon these methods and was tested in the laboratory.

  9. Microfabricated Optical Sensor Probe for the Detection of Esophageal Cancer 

    E-Print Network [OSTI]

    Chinna Balareddy, Karthik Reddy

    2012-10-19T23:59:59.000Z

    spectrometry. The sensor probe consists of a lithographically patterned polymer waveguides chip and three micromachined positioning substrates and source/collection fibers to achieve 45 degree light incidence and collection of spatially resolved diffuse...

  10. Secure Integrated Routing and Localization in Wireless Optical Sensor Networks

    E-Print Network [OSTI]

    Okorafor, Unoma Ndili

    2009-05-15T23:59:59.000Z

    Wireless ad hoc and sensor networks are envisioned to be self-organizing and autonomous networks, that may be randomly deployed where no fixed infrastructure is either feasible or cost-effective. The successful commercialization of such networks...

  11. Optical fiber sensor having a sol-gel fiber core and a method of making

    DOE Patents [OSTI]

    Tao, Shiquan; Jindal, Rajeev; Winstead, Christopher; Singh, Jagdish P.

    2006-06-06T23:59:59.000Z

    A simple, economic wet chemical procedure is described for making sol-gel fibers. The sol-gel fibers made from this process are transparent to ultraviolet, visible and near infrared light. Light can be guided in these fibers by using an organic polymer as a fiber cladding. Alternatively, air can be used as a low refractive index medium. The sol-gel fibers have a micro pore structure which allows molecules to diffuse into the fiber core from the surrounding environment. Chemical and biochemical reagents can be doped into the fiber core. The sol-gel fiber can be used as a transducer for constructing an optical fiber sensor. The optical fiber sensor having an active sol-gel fiber core is more sensitive than conventional evanescent wave absorption based optical fiber sensors.

  12. A new sensor concept for simultaneous measurement of pressure, temperature and thickness of plate structures using modified wave propagation theory 

    E-Print Network [OSTI]

    Lo, Tzu-Wei

    2005-11-01T23:59:59.000Z

    This thesis presents a multi-purpose sensor concept viable for the simultaneous measurement of pressure, temperature and thickness of plate structures. It also establishes the knowledge base necessary for future sensor ...

  13. Final Technical Report - Advanced Optical Sensors to Minimize Energy Consumption in Polymer Extrusion Processes

    SciTech Connect (OSTI)

    Susan J. Foulk

    2012-07-24T23:59:59.000Z

    Project Objective: The objectives of this study are to develop an accurate and stable on-line sensor system to monitor color and composition on-line in polymer melts, to develop a scheme for using the output to control extruders to eliminate the energy, material and operational costs of off-specification product, and to combine or eliminate some extrusion processes. Background: Polymer extrusion processes are difficult to control because the quality achieved in the final product is complexly affected by the properties of the extruder screw, speed of extrusion, temperature, polymer composition, strength and dispersion properties of additives, and feeder system properties. Extruder systems are engineered to be highly reproducible so that when the correct settings to produce a particular product are found, that product can be reliably produced time after time. However market conditions often require changes in the final product, different products or grades may be processed in the same equipment, and feed materials vary from lot to lot. All of these changes require empirical adjustment of extruder settings to produce a product meeting specifications. Optical sensor systems that can continuously monitor the composition and color of the extruded polymer could detect process upsets, drift, blending oscillations, and changes in dispersion of additives. Development of an effective control algorithm using the output of the monitor would enable rapid corrections for changes in materials and operating conditions, thereby eliminating most of the scrap and recycle of current processing. This information could be used to identify extruder systems issues, diagnose problem sources, and suggest corrective actions in real-time to help keep extruder system settings within the optimum control region. Using these advanced optical sensor systems would give extruder operators real-time feedback from their process. They could reduce the amount of off-spec product produced and significantly reduce energy consumption. Also, because blending and dispersion of additives and components in the final product could be continuously verified, we believe that, in many cases, intermediate compounding steps could be eliminated (saving even more time and energy).

  14. Method and apparatus for packaging optical fiber sensors for harsh environments

    DOE Patents [OSTI]

    Pickrell, Gary; Duan, Yuhong; Wang, Anbo

    2005-08-09T23:59:59.000Z

    A package for an optical fiber sensor having a metal jacket surrounding the sensor, and heat-shrink tubing surrounding the metal jacket. The metal jacket is made of a low melting point metal (e.g. lead, tin). The sensor can be disposed in a rigid tube (e.g. stainless steel or glass) that is surrounded by the metal jacket. The metal jacket provides a hermetic, or nearly hermetic seal for the sensor. The package is made by melting the metal jacket and heating the heat shrink tubing at the same time. As the heat-shrink tubing shrinks, it presses the low melting point metal against the sensor, and squeezes out the excess metal.

  15. A loss-based, magnetic field sensor implemented in a ferrofluid infiltrated microstructured polymer optical fiber

    SciTech Connect (OSTI)

    Candiani, A. [Foundation for Research and Technology-Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), Heraklion 70013 Greece (Greece); Department of Information Engineering (DII), University of Parma, Parma 43124 (Italy); Argyros, A.; Leon-Saval, S. G.; Lwin, R. [Institute of Photonics and Optical Science (IPOS), School of Physics, The University of Sydney, Sydney (Australia); Selleri, S. [Department of Information Engineering (DII), University of Parma, Parma 43124 (Italy); Pissadakis, S., E-mail: pissas@iesl.forth.gr [Foundation for Research and Technology-Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), Heraklion 70013 Greece (Greece)

    2014-03-17T23:59:59.000Z

    We report an in-fiber magnetic field sensor based on magneto-driven optical loss effects, while being implemented in a ferrofluid infiltrated microstructured polymer optical fiber. We demonstrate that magnetic field flux changes up to 2000 gauss can be detected when the magnetic field is applied perpendicular to the fiber axis. In addition, the sensor exhibits high polarization sensitivity for the interrogated wavelengths, providing the possibility of both field flux and direction measurements. The underlying physical and guidance mechanisms of this sensing transduction are further investigated using spectrophotometric, light scattering measurements, and numerical simulations, suggesting photonic Hall effect as the dominant physical, transducing mechanism.

  16. Forty-Four Pass Fibre Optic Loop for Improving the Sensitivity of Surface Plasmon Resonance Sensors

    E-Print Network [OSTI]

    Chin B Su; Jun Kameoka

    2007-09-21T23:59:59.000Z

    A forty-four pass fibre optic surface plasmon resonance sensor that enhances detection sensitivity according to the number of passes is demonstrated for the first time. The technique employs a fibre optic recirculation loop that passes the detection spot forty- four times, thus enhancing sensitivity by a factor of forty-four. Presently, the total number of passes is limited by the onset of lasing action of the recirculation loop. This technique offers a significant sensitivity improvement for various types of plasmon resonance sensors that may be used in chemical and biomolecule detections.

  17. Micro optical fiber light source and sensor and method of fabrication thereof

    DOE Patents [OSTI]

    Kopelman, Raoul (Ann Arbor, MI); Tan, Weihong (Ann Arbor, MI); Shi, Zhong-You (Ann Arbor, MI)

    1994-01-01T23:59:59.000Z

    This invention relates generally to the development of and a method of fabricating a micro optical fiber light source. An optical fiber micro-light source is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material. This process allows significant control of the size of the micro light source. Furthermore, photo-chemically attaching an optically active material enables the implementation of the micro-light source in a variety of sensor applications.

  18. Micro optical fiber light source and sensor and method of fabrication thereof

    DOE Patents [OSTI]

    Kopelman, R.; Tan, W.; Shi, Z.Y.

    1994-11-01T23:59:59.000Z

    This invention relates generally to the development of and a method of fabricating a micro optical fiber light source. An optical fiber micro-light source is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material. This process allows significant control of the size of the micro light source. Furthermore, photo-chemically attaching an optically active material enables the implementation of the micro-light source in a variety of sensor applications. 4 figs.

  19. Towards Fully Integrated High Temperature Wireless Sensors Using GaN-based HEMT Devices

    SciTech Connect (OSTI)

    Kuruganti, Phani Teja [ORNL; Islam, Syed K [ORNL; Huque, Mohammad A [ORNL

    2008-01-01T23:59:59.000Z

    Wireless sensors which are capable of working at extreme environments can significantly improve the efficiency and performance of industrial processes by facilitating better control systems. GaN, a widely researched wide bandgap material, has the potential to be used both as a sensing material and to fabricate control electronics, making it a prime candidate for high temperature integrated wireless sensor fabrication. In this paper we are presenting an experimental study on AlGaN/GaN HEMT's performance at higher temperature (up to 300 C). From test results, DC and microwave parameters at different temperatures were extracted.

  20. December 1, 2000 / Vol. 25, No. 23 / OPTICS LETTERS 1687 Hybrid curvature and gradient wave-front sensor

    E-Print Network [OSTI]

    Dainty, Chris

    Received July 26, 2000 A new wave-front sensor for adaptive optics that gives signals for the curvatureDecember 1, 2000 / Vol. 25, No. 23 / OPTICS LETTERS 1687 Hybrid curvature and gradient wave-front sensor C. Paterson and J. C. Dainty The Blackett Laboratory, Imperial College, London, SW7 2BZ, UK

  1. In the paper, we describe an optical system which is capable of providing external access to both the sensor and

    E-Print Network [OSTI]

    Hua, Hong

    an intermediate image plane which is optically conjugated to the camera sensor. As indicated by its name, a relayAbstract In the paper, we describe an optical system which is capable of providing external access to both the sensor and the lens aperture (i.e., projection center) of a conventional camera. The proposed

  2. Development of Nano-crystalline Doped-Ceramic Enabled Fiber Sensors for High Temperature In-Situ Monitoring of Fossil Fuel Gases

    SciTech Connect (OSTI)

    Hai Xiao; Junhang Dong; Jerry Lin; Van Romero

    2011-12-31T23:59:59.000Z

    This is a final technical report for the first project year from July 1, 2005 to Jan 31, 2012 for DoE/NETL funded project â??DE-FC26-05NT42439: Development of Nanocrystalline Doped-Ceramic Enabled Fiber Sensors for High Temperature In-Situ Monitoring of Fossil Fuel Gases.â? This report summarizes the technical progresses and achievements towards the development of novel nanocrystalline doped ceramic material-enabled optical fiber sensors for in situ and real time monitoring the gas composition of flue or hot gas streams involved in fossil-fuel based power generation and hydrogen production.

  3. Distributed fiber optic intrusion sensor system for monitoring long perimeters

    E-Print Network [OSTI]

    Juarez, Juan C.

    2009-06-02T23:59:59.000Z

    Perturbation ........................ 17 G. Frequency Drift Measurement................................................................... 19 III ERBIUM DOPED FIBER LASER CHARACTERIZATION........................ 22 A. Er:Fiber Laser... .................................................................................................... 22 12. Experimental setup for fiber laser used in the intrusion sensor system ............. 24 13. Spectral linewidth scan of Erbium doped fiber laser ......................................... 24 14. Delayed self-heterodyne test setup...

  4. Manufacturing challenges of optical current and voltage sensors for utility applications

    SciTech Connect (OSTI)

    Yakymyshyn, C.P. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Brubaker, M.A. [Los Alamos National Lab., NM (United States); Johnston, P.M. [Johnston (Paul M.), Raleigh, NC (United States); Reinbold, C. [ABB High Voltage Switchgear, Greensburg, PA (United States)

    1997-12-01T23:59:59.000Z

    Measurement of voltages and currents in power transmission and distribution systems are critical to the electric utility industry for both revenue metering and reliability. Nonconventional instrument transformers based on intensity modulation of optical signals have been reported in the literature for more than 20 years. Recently described devices using passive bulk optical sensor elements include the Electro-Optic Voltage Transducer (EOVT) and Magneto-Optic Current Transducer (MOCT). These technologies offer substantial advantages over conventional instrument transformers in accuracy, optical isolation bandwidth, environmental compatibility, weight and size. This paper describes design and manufacturing issues associated with the EOVT and the Optical Metering Unit (OMU) recently introduced by ABB with field installation results presented for prototype units in the 345 kV and 420 kV voltage classes. The OMU incorporates an EOVT and MOCT to monitor the voltage and current on power transmission lines using a single free-standing device.

  5. MRI-compatible Haptics: Feasibility of using optical fiber Bragg grating strain-sensors to detect deflection of needles in an MRI environment

    E-Print Network [OSTI]

    Park, Yong-Lae

    MRI-compatible Haptics: Feasibility of using optical fiber Bragg grating strain-sensors to detect fiber-optic-based force and deflection sensors based on fiber Bragg grating (FBG) technology have been was developed using a single optical fiber and an MRI compatible biopsy needle (22ga x 15cm). The FBG sensor

  6. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS, VOL. 3, NO. 6, DECEMBER 2009 415 A Cantilever Sensor With an Integrated Optical

    E-Print Network [OSTI]

    Rubloff, Gary W.

    Sensor With an Integrated Optical Readout for Detection of Enzymatically Produced Homocysteine Stephan T--Microcantilever sensors have been recognized as a promising sensor platform for various chemical and biological ap involves elaborate off-chip setups with free-space optics. An improved device, known as the optical

  7. D. A. Cohen, Y. Chang, A. F. J. Levi, H. Fetterman, and I. Newberg: `Optically-controlled serially-fed phased array sensor' page

    E-Print Network [OSTI]

    Levi, Anthony F. J.

    -fed phased array sensor' page IEEE Photonics Technol. Lett. 8, 1683-1685 (1996). 1 Optically Newberg Abstract A new type of RF-photonic sensor design which uses an optical serially-fed phased array. Fetterman, and I. Newberg: `Optically-controlled serially-fed phased array sensor' page IEEE Photonics

  8. Wall shear stress sensor based on the optical resonances of dielectric microspheres This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Ötügen, Volkan

    Wall shear stress sensor based on the optical resonances of dielectric microspheres This article (2011) 075203 (9pp) doi:10.1088/0957-0233/22/7/075203 Wall shear stress sensor based on the optical an optical wall shear stress sensor based on the whispering gallery mode (WGM) shifts of dielectric micro

  9. FLUORESCENCE AND FIBER-OPTICS BASED REAL-TIME THICKNESS SENSOR FOR DYNAMIC LIQUID FILMS

    E-Print Network [OSTI]

    Narain, Amitabh

    /analyzed the incident reflected waves to identify and measure the total transit time of the sound wave (of known wave-speed1 FLUORESCENCE AND FIBER-OPTICS BASED REAL-TIME THICKNESS SENSOR FOR DYNAMIC LIQUID FILMS T. W. Ng/disadvantages of many known liquid film thickness sensing devices (viz. conductivity probes, reflectance based fiber

  10. AISI/DOE Advanced Process Control Program Vol. 1 of 6: Optical Sensors and Controls for Improved Basic Oxygen Furnace Operations

    SciTech Connect (OSTI)

    Sarah Allendorf; David Ottesen; Donald Hardesty

    2002-01-31T23:59:59.000Z

    The development of an optical sensor for basic oxygen furnace (BOF) off-gas composition and temperature in this Advanced Process Control project has been a laboratory spectroscopic method evolve into a pre-commercialization prototype sensor system. The sensor simultaneously detects an infrared tunable diode laser ITDL beam transmitted through the process off-gas directly above the furnace mouth, and the infrared greybody emission from the particulate-laden off-gas stream. Following developmental laboratory and field-testing, the sensor prototype was successfully tested in four long-term field trials at Bethlehem Steel's Sparrows Point plant in Baltimore, MD> The resulting optical data were analyzed and reveal correlations with four important process variables: (1) bath turndown temperature; (2) carbon monoxide post-combustion control; (2) bath carbon concentration; and (4) furnace slopping behavior. The optical sensor measurement of the off-gas temperature is modestly correlated with bath turndown temperature. A detailed regression analysis of over 200 heats suggests that a dynamic control level of +25 Degree F can be attained with a stand-alone laser-based optical sensor. The ability to track off-gas temperatures to control post-combustion lance practice is also demonstrated, and may be of great use in optimizing post-combustion efficiency in electric furnace steelmaking operations. In addition to the laser-based absorption spectroscopy data collected by this sensor, a concurrent signal generated by greybody emission from the particle-laden off-gas was collected and analyzed. A detailed regression analysis shows an excellent correlation of a single variable with final bath turndown carbon concentration. Extended field trials in 1998 and early 1999 show a response range from below 0.03% to a least 0.15% carbon concentration with a precision of +0.0007%. Finally, a strong correlation between prolonged drops in the off-gas emission signal and furnace slopping events was observed. A simple computer algorithm was written that successfully predicts furnace slopping for 90% of the heats observed; over 80% are predicted with at least a 30-second warning prior to the initial slopping events,

  11. Homogenization studies for optical sensors based on sculptured thin films 

    E-Print Network [OSTI]

    Jamaian, Siti Suhana

    2013-07-01T23:59:59.000Z

    In this thesis we investigate theoretically various types of sculptured thin film (STF) envisioned as platforms for optical sensing. A STF consists of an array of parallel nanowires which can be grown on a substrate using ...

  12. High-temperature potentiometric oxygen sensor with internal reference

    DOE Patents [OSTI]

    Routbort, Jules L. (Hinsdale, IL); Singh, Dileep (Naperville, IL); Dutta, Prabir K. (Worthington, OH); Ramasamy, Ramamoorthy (North Royalton, OH); Spirig, John V. (Columbus, OH); Akbar, Sheikh (Hilliard, OH)

    2011-11-15T23:59:59.000Z

    A compact oxygen sensor is provided, comprising a mixture of metal and metal oxide an enclosure containing said mixture, said enclosure capable of isolating said mixture from an environment external of said enclosure, and a first wire having a first end residing within the enclosure and having a second end exposed to the environment. Also provided is a method for the fabrication of an oxygen sensor, the method comprising confining a metal-metal oxide solid mixture to a container which consists of a single material permeable to oxygen ions, supplying an electrical conductor having a first end and a second end, whereby the first end resides inside the container as a reference (PO.sub.2).sup.ref, and the second end resides outside the container in the atmosphere where oxygen partial pressure (PO.sub.2).sup.ext is to be measured, and sealing the container with additional single material such that grain boundary sliding occurs between grains of the single material and grains of the additional single material.

  13. An Experimental Evaluation of HVAC-Grade Carbon-Dioxide Sensors: Part 3, Humidity, Temperature, and Pressure Sensitivity Test Results

    SciTech Connect (OSTI)

    Shrestha, Som S [ORNL; Maxwell, Dr. Gregory [Iowa State University

    2010-01-01T23:59:59.000Z

    This is the third paper in a four-part series reporting on the test and evaluation of typical carbon-dioxide sensors used in building HVAC applications. Fifteen models of NDIR HVAC-grade CO2 sensors were tested and evaluated to determine the humidity, temperature, and pressure sensitivity of the sensors. This paper reports the performance of the sensors at various relative humidity, temperature, and pressure levels common to building HVAC applications and provides a comparison with manufacturer specifications. Among the 15 models tested, eight models have a single-lamp, single-wavelength configuration, four models have a dual-lamp, single-wavelength configuration, and three models have a single-lamp, dual-wavelength configuration. The sensors were tested in a chamber specifically fabricated for this research. A description of the apparatus and the method of test are described in Part 1 (Shrestha and Maxwell 2009). The test result showed a wide variation in humidity, temperature, and pressure sensitivity of CO2 sensors among manufacturers. In some cases, significant variations in sensor performance exist between sensors of the same model. Even the natural variation in relative humidity could significantly vary readings of some CO2 sensor readings. The effects of temperature and pressure variation on NDIR CO2 sensors are unavoidable without an algorithm to compensate for the changes. For the range of temperature and pressure variation in an air-conditioned space, the effect of pressure variation is more significant compared to the effect of temperature variation.

  14. Structural and environmental monitoring of tracker and vertex systems using Fiber Optic Sensors

    E-Print Network [OSTI]

    David Moya; Iván Vila

    2012-03-01T23:59:59.000Z

    Fibre optic sensors (FOS) are an established technique for environmental and deformation monitoring in several areas like civil engineering, aerospace, and energy. Their immunity to electromagnetic and magnetic fields and nuclear environments, its small size, multiplexing capability and the possibility to be embedded make them an attractive technology for the structural and environmental monitoring of collider particle physics experiments. Between all the possible Fibre Optic sensors FBGs (Fiber Bragg Grating) seems to be the best solution for HEP applications. The first step was to characterize FBG sensors for it use in High Energy Physics environment. During last two years we have checked the resistance of the Fibre Bragg Grating sensors to radiation. Two irradiation campaigns with protons have been done at CNA (Centro Nacional de Aceleradores). In the near future these sensors are being planned to be used in detectors (the closest one Belle II.). Several work on integration issues in Belle II PXD-SVD, and checking for environmental and deformation monitoring in the detectors inner part has been done.

  15. Riboswitch-based sensor in low optical background Svetlana V. Harbaugh, Molly E. Davidson, Yaroslav G. Chushak*

    E-Print Network [OSTI]

    Riboswitch-based sensor in low optical background Svetlana V. Harbaugh, Molly E. Davidson, Yaroslav have coupled a synthetic riboswitch to an optical reporter assay based on fluorescence resonance energy protease. Cells expressing the riboswitch showed a marked optical difference in fluorescence emission

  16. Large Dynamic Range Electromagnetic FieldLarge Dynamic Range Electromagnetic Field Sensor based on Domain Inverted Electro-Optic

    E-Print Network [OSTI]

    Texas at Austin, University of

    Large Dynamic Range Electromagnetic FieldLarge Dynamic Range Electromagnetic Field Sensor based on Domain Inverted Electro-Optic Polymer Directional CouplerPolymer Directional Coupler Alan X. Wang Ray T. Chen Omega Optics Inc Austin TXOmega Optics Inc., Austin, TX -1- #12;Application of Electric Field

  17. Electro-optic voltage sensor for sensing voltage in an E-field

    DOE Patents [OSTI]

    Woods, Gregory K. (Idaho Falls, ID); Renak, Todd W. (Idaho Falls, ID)

    1999-01-01T23:59:59.000Z

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  18. Electro-optic voltage sensor for sensing voltage in an E-field

    DOE Patents [OSTI]

    Woods, G.K.; Renak, T.W.

    1999-04-06T23:59:59.000Z

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages is disclosed. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam`s polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured. 18 figs.

  19. A two-mode fiber optic-bending sensor

    E-Print Network [OSTI]

    Covington, Charles Eric

    1993-01-01T23:59:59.000Z

    It is shown that a small slope in the refractive index profile of an optical fiber causes the two lowest order spatial modes to travel different distances from the geometrical center of the fiber. This effect increases by orders of magnitude...

  20. Elevated Temperature Sensors for On-Line Critical Equipment Health Monitoring

    SciTech Connect (OSTI)

    James Sebastian

    2003-09-29T23:59:59.000Z

    The objective of this research program is to improve high temperature piezoelectric aluminum nitride (AlN) sensor technology to make it useful for instrumentation and health monitoring of current and future electrical power generation equipment. The program will extend the temperature range of the sensor from approximately 700 C to above 1000 C, and ultrasonic coupling to objects at these temperatures will be investigated and tailored for use with the sensor. The chemical vapor deposition (CVD) AlN deposition process was successfully transferred from film production on tungsten carbide substrates to titanium alloy and silicon carbide (SiC) substrates. Further evaluation of the piezoelectric films on titanium caused it to be discarded as a candidate material due to an excessive thermal expansion coefficient mismatch, causing film failure upon reheating from room temperature. Deposition on SiC is proceeding well, with a highly conductive grade of silicon carbide required for practical use. Additional substrate materials, including refractory metals and conductive ceramics, have been considered but are generally not promising in light of the experience with titanium. Pulsed laser deposition (PLD) was investigated as an alternate means of creating the films as an alternative to CVD. A concurrent effort has focused on investigation of means of coupling ultrasound from the sensor into the test object at high temperature. A literature search combined with preliminary experimentation has resulted in the selection of two methods for coupling: low melting point glasses and metal foil- pressure couplant. The work in the next two years of the program will include continued improvement of the CVD deposition process, experimental testing of films and coupling at high temperatures, and a laboratory demonstration of the sensor in a simulated industrial application

  1. Modeling and Validation of Performance Limitations for the Optimal Design of Interferometric and Intensity-Modulated Fiber Optic Displacement Sensors

    SciTech Connect (OSTI)

    Moro, Erik A. [Los Alamos National Laboratory

    2012-06-07T23:59:59.000Z

    Optical fiber sensors offer advantages over traditional electromechanical sensors, making them particularly well-suited for certain measurement applications. Generally speaking, optical fiber sensors respond to a desired measurand through modulation of an optical signal's intensity, phase, or wavelength. Practically, non-contacting fiber optic displacement sensors are limited to intensity-modulated and interferometric (or phase-modulated) methodologies. Intensity-modulated fiber optic displacement sensors relate target displacement to a power measurement. The simplest intensity-modulated sensor architectures are not robust to environmental and hardware fluctuations, since such variability may cause changes in the measured power level that falsely indicate target displacement. Differential intensity-modulated sensors have been implemented, offering robustness to such intensity fluctuations, and the speed of these sensors is limited only by the combined speed of the photodetection hardware and the data acquisition system (kHz-MHz). The primary disadvantages of intensity-modulated sensing are the relatively low accuracy (?m-mm for low-power sensors) and the lack of robustness, which consequently must be designed, often with great difficulty, into the sensor's architecture. White light interferometric displacement sensors, on the other hand, offer increased accuracy and robustness. Unlike their monochromatic-interferometer counterparts, white light interferometric sensors offer absolute, unambiguous displacement measurements over large displacement ranges (cm for low-power, 5 mW, sources), necessitating no initial calibration, and requiring no environmental or feedback control. The primary disadvantage of white light interferometric displacement sensors is that their utility in dynamic testing scenarios is limited, both by hardware bandwidth and by their inherent high-sensitivity to Doppler-effects. The decision of whether to use either an intensity-modulated interferometric sensor depends on an appropriate performance function (e.g., desired displacement range, accuracy, robustness, etc.). In this dissertation, the performance limitations of a bundled differential intensity-modulated displacement sensor are analyzed, where the bundling configuration has been designed to optimize performance. The performance limitations of a white light Fabry-Perot displacement sensor are also analyzed. Both these sensors are non-contacting, but they have access to different regions of the performance-space. Further, both these sensors have different degrees of sensitivity to experimental uncertainty. Made in conjunction with careful analysis, the decision of which sensor to deploy need not be an uninformed one.

  2. Temperature Control Framework Using Wireless Sensor Networks and Geostatistical Analysis for Total Spatial Awareness

    E-Print Network [OSTI]

    Fan, Jeffrey

    cooling and heating mechanisms in buildings at every location for improved user comfort. Keywords ­ Smart presents a novel framework for intelligent temperature control in smart homes using Wireless Sensor Analysis; Classical Variography; Ordinary Point Kriging I. INTRODUCTION Research involving smart homes has

  3. Performance Enhancement of Raman-based Distributed Temperature Sensors using Simplex Codes

    E-Print Network [OSTI]

    Park, Namkyoo

    Performance Enhancement of Raman-based Distributed Temperature Sensors using Simplex Codes G, Seoul National University, Korea. E-mail: nkpark@plaza.snu.ac.kr Abstract: Using 63 bit simplex coding]. The use of simplex coding (S-coding) in conjunction with OTDR can be effectively used to enhance

  4. Piezotronic Effect on ZnO Nanowire Film Based Temperature Sensor Limin Zhang,,

    E-Print Network [OSTI]

    Wang, Zhong L.

    film, wet chemical deposition, temperature sensor, bimetallic strip 1. INTRODUCTION Recently, Wurtzite-3 Due to the noncentral symmetric hexagonal structure, a Wurtzite-structured material generates, most of the fabricated piezotronic devices are based on one-dimensional (1D) Wurtzite nanostructures

  5. Special Sensor Microwave Imager and Sounder (SSMIS) Antenna Brightness Temperature Data Record (TDR)

    E-Print Network [OSTI]

    Special Sensor Microwave Imager and Sounder (SSMIS) Antenna Brightness Temperature Data Record (TDR/NESDIS/Center for Satellite Applications and Research Contributors from: Banghua Yan (Lead), QSS/JCSDA Ninghai Sun, IMSG, Metoffice, UK Yong Han, STAR/JCSDA Mark Liu, QSS/JCSDA Distribution to: Ralph Ferrrao, STAR Tom Schott, OSD

  6. Elastomeric optical fiber sensors and method for detecting and measuring events occurring in elastic materials

    DOE Patents [OSTI]

    Muhs, Jeffrey D. (Lenoir City, TN); Capps, Gary J. (Knoxville, TN); Smith, David B. (Oak Ridge, TN); White, Clifford P. (Knoxville, TN)

    1994-01-01T23:59:59.000Z

    Fiber optic sensing means for the detection and measurement of events such as dynamic loadings imposed upon elastic materials including cementitious materials, elastomers, and animal body components and/or the attrition of such elastic materials are provided. One or more optical fibers each having a deformable core and cladding formed of an elastomeric material such as silicone rubber are embedded in the elastic material. Changes in light transmission through any of the optical fibers due the deformation of the optical fiber by the application of dynamic loads such as compression, tension, or bending loadings imposed on the elastic material or by the attrition of the elastic material such as by cracking, deterioration, aggregate break-up, and muscle, tendon, or organ atrophy provide a measurement of the dynamic loadings and attrition. The fiber optic sensors can be embedded in elastomers subject to dynamic loadings and attrition such as commonly used automobiles and in shoes for determining the amount and frequency of the dynamic loadings and the extent of attrition. The fiber optic sensors are also useable in cementitious material for determining the maturation thereof.

  7. Analysis of roll gap heat transfers in hot steel strip rolling through roll temperature sensors and heat transfer models

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Analysis of roll gap heat transfers in hot steel strip rolling through roll temperature sensors and heat transfer models N. Legrand1,a , N. Labbe1,b D. Weisz-Patrault2,c , A. Ehrlacher2,d , T. Luks3,e heat transfers during pilot hot steel strip rolling. Two types of temperature sensors (drilled and slot

  8. An Optical Backscatter Sensor for Particulate Matter Measurement

    SciTech Connect (OSTI)

    Parks, II, James E [ORNL; Prikhodko, Vitaly Y [ORNL; Partridge Jr, William P [ORNL

    2009-01-01T23:59:59.000Z

    Diesel engines are prone to emit particulate matter (PM) emissions under certain operation conditions. In-cylinder production of PM from diesel combustion control can occur under a wide variety of operating conditions, and in some cases, operation of a multi-cylinder engine can further complicate PM emissions due to variations in air or fuel charge due to manifold mixing effects. In this study, a probe for detecting PM in diesel exhaust was evaluated on a light-duty diesel engine. The probe is based on an optical backscattering effect. Due to the optical nature of the probe, PM sensing can occur at high rates. The feasibility of the probe for examining PM emissions in the exhaust manifold will be discussed.

  9. Fiber-optic Fabry-Perot ultrasound sensor

    E-Print Network [OSTI]

    Alcoz, Jorge Jose

    1989-01-01T23:59:59.000Z

    -Perot interferometer. A mirror is produced by joining a fiber coated on the end with a T;02 film to an uncoated fiber by electric arc splicing. The acoustic field changes the index of refraction inside the interferometer cavity through the strain optic effect, thus... displays of-the response of S2 to a 150 KHz wave, for the static phase shift changing x/2. A second harmonic is ge~ when the interferometer is in quadrature . 10. Oscilloscope displays of detected signal for the same 350 KHz acoustic wave a...

  10. Conjugate adaptive optics in widefield microscopy with an extended-source wavefront sensor

    E-Print Network [OSTI]

    Li, Jiang; Paudel, Hari; Barankov, Roman; Bifano, Thomas; Mertz, Jerome

    2015-01-01T23:59:59.000Z

    Adaptive optics is a strategy to compensate for sample-induced aberrations in microscopy applications. Generally, it requires the presence of "guide stars" in the sample to serve as localized reference targets. We describe an implementation of conjugate adaptive optics that is amenable to widefield (i.e. non-scanning) microscopy, and can provide aberration corrections over potentially large fields of view without the use of guide stars. A unique feature of our implementation is that it is based on wavefront sensing with a single-shot partitioned-aperture sensor that provides large dynamic range compatible with extended samples. Combined information provided by this sensor and the imaging camera enable robust image de-blurring based on a rapid estimation of sample and aberrations obtained by closed-loop feedback. We present the theoretical principle of our technique and proof of concept experimental demonstrations.

  11. Environmental temperature sensing using Raman spectra DTS fiber-optic methods

    E-Print Network [OSTI]

    Selker, John

    Environmental temperature sensing using Raman spectra DTS fiber-optic methods Scott W. Tyler,1 John January 2009. [1] Raman spectra distributed temperature sensing (DTS) by fiber-optic cables has recently sensing using Raman spectra DTS fiber-optic methods, Water Resour. Res., 45, W00D23, doi:10.1029/2008WR

  12. Fabrication of Optical Fiber Mechanical Shock Sensors for the Los Alamos HERT (High Explosive Radio Telemetry) Project

    SciTech Connect (OSTI)

    P. E. Klingsporn

    2005-11-14T23:59:59.000Z

    This document lists the requirements for the fiber optic mechanical shock sensor for the Los Alamos HERT (High Explosive Radio Telemetry) project and provides detailed process steps for fabricating, testing, and assembling the fiber shock sensors for delivery to Los Alamos.

  13. A study of semiconductor laser noise and its effect on fiber optic sensor performance 

    E-Print Network [OSTI]

    Lee, Wanku

    1994-01-01T23:59:59.000Z

    A STUDY OF SEMICONDUCTOR LASER NOISE AND ITS EFFECT ON FISER OPTIC SENSOR PERFORMANCE A Thesis by WANKU LEE Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved... as to style and content by: F. aylor (Chair o Committee) D, c 0. Eknoyan (Member) Li ngs ( ember G. Cote (Member) A. , Patton (Head o Department) August 1994 Major Subject: Electrical Engineering ABSTRACT A Study of Semiconductor Laser Noise...

  14. A study of semiconductor laser noise and its effect on fiber optic sensor performance

    E-Print Network [OSTI]

    Lee, Wanku

    1994-01-01T23:59:59.000Z

    A STUDY OF SEMICONDUCTOR LASER NOISE AND ITS EFFECT ON FISER OPTIC SENSOR PERFORMANCE A Thesis by WANKU LEE Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved... as to style and content by: F. aylor (Chair o Committee) D, c 0. Eknoyan (Member) Li ngs ( ember G. Cote (Member) A. , Patton (Head o Department) August 1994 Major Subject: Electrical Engineering ABSTRACT A Study of Semiconductor Laser Noise...

  15. Fiber optic sensor employing successively destroyed coupled points or reflectors for detecting shock wave speed and damage location

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    1995-01-01T23:59:59.000Z

    A shock velocity and damage location sensor providing a means of measuring shock speed and damage location. The sensor consists of a long series of time-of-arrival "points" constructed with fiber optics. The fiber optic sensor apparatus measures shock velocity as the fiber sensor is progressively crushed as a shock wave proceeds in a direction along the fiber. The light received by a receiving means changes as time-of-arrival points are destroyed as the sensor is disturbed by the shock. The sensor may comprise a transmitting fiber bent into a series of loops and fused to a receiving fiber at various places, time-of-arrival points, along the receiving fibers length. At the "points" of contact, where a portion of the light leaves the transmitting fiber and enters the receiving fiber, the loops would be required to allow the light to travel backwards through the receiving fiber toward a receiving means. The sensor may also comprise a single optical fiber wherein the time-of-arrival points are comprised of reflection planes distributed along the fibers length. In this configuration, as the shock front proceeds along the fiber it destroys one reflector after another. The output received by a receiving means from this sensor may be a series of downward steps produced as the shock wave destroys one time-of-arrival point after another, or a nonsequential pattern of steps in the event time-of-arrival points are destroyed at any point along the sensor.

  16. Fiber optic sensor employing successively destroyed coupled points or reflectors for detecting shock wave speed and damage location

    DOE Patents [OSTI]

    Weiss, J.D.

    1995-08-29T23:59:59.000Z

    A shock velocity and damage location sensor providing a means of measuring shock speed and damage location is disclosed. The sensor consists of a long series of time-of-arrival ``points`` constructed with fiber optics. The fiber optic sensor apparatus measures shock velocity as the fiber sensor is progressively crushed as a shock wave proceeds in a direction along the fiber. The light received by a receiving means changes as time-of-arrival points are destroyed as the sensor is disturbed by the shock. The sensor may comprise a transmitting fiber bent into a series of loops and fused to a receiving fiber at various places, time-of-arrival points, along the receiving fibers length. At the ``points`` of contact, where a portion of the light leaves the transmitting fiber and enters the receiving fiber, the loops would be required to allow the light to travel backwards through the receiving fiber toward a receiving means. The sensor may also comprise a single optical fiber wherein the time-of-arrival points are comprised of reflection planes distributed along the fibers length. In this configuration, as the shock front proceeds along the fiber it destroys one reflector after another. The output received by a receiving means from this sensor may be a series of downward steps produced as the shock wave destroys one time-of-arrival point after another, or a nonsequential pattern of steps in the event time-of-arrival points are destroyed at any point along the sensor. 6 figs.

  17. Optical Sensors for Post Combustion Control in Electric Arc Furnace Steelmaking (TRP 9851)

    SciTech Connect (OSTI)

    Sarah W. Allendorf; David K. Ottesen; Robert W. Green; Donald R. Hardesty; Robert Kolarik; Howard Goodfellow; Euan Evenson; Marshall Khan; Ovidiu Negru; Michel Bonin; Soren Jensen

    2003-12-31T23:59:59.000Z

    Working in collaboration with Stantec Global Technologies, Process Metrix Corporation, and The Timken Company, Sandia National Laboratories constructed and evaluated a novel, laser-based off-gas sensor at the electric arc furnace facility of Timken's Faircrest Steel Plant (Canton, Ohio). The sensor is based on a mid-infrared tunable diode laser (TDL), and measures the concentration and temperature of specific gas species present in the off-gas emanating from the EAF. The laser beam is transmitted through the gas stream at the fourth hole of the EAF, and provides a real-time, in situ measurement that can be used for process optimization. Two sets of field tests were performed in parallel with Stantec's extractive probe off-gas system, and the tests confirm the TDL sensor's operation and applicability for electric steel making. The sensor measures real-time, in situ line-of-sight carbon monoxide (CO) concentrations between 5% and 35% CO, and measures off-gas temperature in the range of 1400 to 1900 K. In order to achieve commercial-ready status, future work is required to extend the sensor for simultaneous CO and CO{sub 2} concentration measurements. In addition, long-term endurance tests including process optimization must be completed.

  18. Sensors and Actuators A 125 (2006) 170177 Thin film temperature sensor for real-time measurement

    E-Print Network [OSTI]

    Mench, Matthew M.

    2006-01-01T23:59:59.000Z

    , a Fuel Cell Dynamic and Diagnostic Laboratory, and Department of Mechanical and Nuclear Engineering of electrolyte temperature in a polymer electrolyte fuel cell Suhao Hea, Matthew M. Mencha, Srinivas Tadigadapab electrolyte fuel cell (PEFC). A patterned thin film gold thermistor embedded in a 16 m thick parylene film

  19. Testing of Performance of Optical Fibers Under Irradiation in Intense Radiation Fields, When Subjected to Very High Temperatures

    SciTech Connect (OSTI)

    Blue, Thomas; Windl, Wolfgang; Dickerson, Bryan

    2013-01-03T23:59:59.000Z

    The primary objective of this project is to measure and model the performance of optical fibers in intense radiation fields when subjected to very high temperatures. This research will pave the way for fiber optic and optically based sensors under conditions expected in future high-temperature gas-cooled reactors. Sensor life and signal-to-noise ratios are susceptible to attenuation of the light signal due to scattering and absorbance in the fibers. This project will provide an experimental and theoretical study of the darkening of optical fibers in high-radiation and high-temperature environments. Although optical fibers have been studied for moderate radiation fluence and flux levels, the results of irradiation at very high temperatures have not been published for extended in-core exposures. Several previous multi-scale modeling efforts have studied irradiation effects on the mechanical properties of materials. However, model-based prediction of irradiation-induced changes in silica�s optical transport properties has only recently started to receive attention due to possible applications as optical transmission components in fusion reactors. Nearly all damage-modeling studies have been performed in the molecular-dynamics domain, limited to very short times and small systems. Extended-time modeling, however, is crucial to predicting the long-term effects of irradiation at high temperatures, since the experimental testing may not encompass the displacement rate that the fibers will encounter if they are deployed in the VHTR. The project team will pursue such extended-time modeling, including the effects of the ambient and recrystallization. The process will be based on kinetic MC modeling using the concept of amorphous material consisting of building blocks of defect-pairs or clusters, which has been successfully applied to kinetic modeling in amorphized and recrystallized silicon. Using this procedure, the team will model compensation for rate effects, and the interplay of rate effects with the effects of annealing, to accurately predict the fibers� reliability and expected lifetime

  20. Characterization of neutron transmutation doped (NTD) Ge for low temperature sensor development

    E-Print Network [OSTI]

    S. Mathimalar; V. Singh; N. Dokania; V. Nanal; R. G. Pillay; S. Pal; S. Ramakrishnan; A. Shrivastava; Priya Maheshwari; P. K. Pujari; S. Ojha; D. Kanjilal; K. C. Jagadeesan; S. V. Thakare

    2014-12-05T23:59:59.000Z

    Development of NTD Ge sensors has been initiated for low temperature (mK) thermometry in The India-based Tin detector (TIN.TIN). NTD Ge sensors are prepared by thermal neutron irradiation of device grade Ge samples at Dhruva reactor, BARC, Mumbai. Detailed measurements have been carried out in irradiated samples for estimating the carrier concentration and fast neutron induced defects. The Positron Annihilation Lifetime Spectroscopy (PALS) measurements indicated monovacancy type defects for all irradiated samples, while Channeling studies employing RBS with 2 MeV alpha particles, revealed no significant defects in the samples exposed to fast neutron fluence of $\\sim 4\\times10^{16}/cm^2$. Both PALS and Channeling studies have shown that vacuum annealing at 600 $^\\circ$C for $\\sim2$ hours is sufficient to recover the damage in the irradiated samples, thereby making them suitable for the sensor development.

  1. Development of High Temperature/High Sensitivity Novel Chemical Resistive Sensor

    SciTech Connect (OSTI)

    Chen, Chonglin; Nash, Patrick; Ma, Chunrui; Enriquez, Erik; Wang, Haibing; Xu, Xing; Bao, Shangyong; Collins, Gregory

    2013-08-13T23:59:59.000Z

    The research has been focused to design, fabricate, and develop high temperature/high sensitivity novel multifunctional chemical sensors for the selective detection of fossil energy gases used in power and fuel systems. By systematically studying the physical properties of the LnBaCo{sub 2}O{sub 5+d} (LBCO) [Ln=Pr or La] thin?films, a new concept chemical sensor based high temperature chemical resistant change has been developed for the application for the next generation highly efficient and near zero emission power generation technologies. We also discovered that the superfast chemical dynamic behavior and an ultrafast surface exchange kinetics in the highly epitaxial LBCO thin films. Furthermore, our research indicates that hydrogen can superfast diffuse in the ordered oxygen vacancy structures in the highly epitaxial LBCO thin films, which suggest that the LBCO thin film not only can be an excellent candidate for the fabrication of high temperature ultra sensitive chemical sensors and control systems for power and fuel monitoring systems, but also can be an excellent candidate for the low temperature solid oxide fuel cell anode and cathode materials.

  2. channel voltage sensor+ether--go-go K Optical detection of rate-determining ion-modulated conformational changes of the

    E-Print Network [OSTI]

    Bezanilla, Francisco

    channel voltage sensor+ether-à-go-go K Optical detection of rate-determining ion electrophysiological and optical approach. We find that a fluorescent probe attached near S4 in the voltage sensor.pnas.org/misc/reprints.shtml To order reprints, see: Notes: #12;Optical detection of rate-determining ion-modulated conformational

  3. Journal of Materials Science, 2009. 44(6): p. 1560-1571 Whispering Gallery Mode-Based Micro-Optical Sensors for Structural Health Monitoring

    E-Print Network [OSTI]

    Gupta, Nikhil

    used in materials include piezoelectric particles, acoustic emission sensors and optical fibers. Each. Use of fiber-optic sensors is advantageous in composite materials because they can become an integral1560 Journal of Materials Science, 2009. 44(6): p. 1560-1571 Whispering Gallery Mode-Based Micro-Optical

  4. Development of an Acoustic Sensor On-Line Gas Temperature Measurement in Gasifiers

    SciTech Connect (OSTI)

    Peter Ariessohn

    2008-06-30T23:59:59.000Z

    This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) Program Solicitation DE-PS26-02NT41422 and specifically addresses Technical Topical Area 2 - Gasification Technologies. The project team includes Enertechnix, Inc. as the main contractor and ConocoPhillips Company as a technical partner, who also provides access to the SG Solutions Gasification Facility (formerly Wabash River Energy Limited), host for the field-testing portion of the research. The objective of this project was to adapt acoustic pyrometer technology to make it suitable for measuring gas temperature inside a coal gasifier, to develop a prototype sensor based on this technology, and to demonstrate its performance through testing on a commercial gasifier. The project was organized in three phases, each of approximately one year duration. The first phase consisted of researching a variety of sound generation and coupling approaches suitable for use with a high pressure process, evaluation of the impact of gas composition variability on the acoustic temperature measurement approach, evaluation of the impact of suspended particles and gas properties on sound attenuation, evaluation of slagging issues and development of concepts to deal with this issue, development and testing of key prototype components to allow selection of the best approaches, and development of a conceptual design for a field prototype sensor that could be tested on an operating gasifier. The second phase consisted of designing and fabricating a series of prototype sensors, testing them in the laboratory, and developing a conceptual design for a field prototype sensor. The third phase consisted of designing and fabricating the field prototype, and testing it in the lab and in a commercial gasifier to demonstrate the ability to obtain accurate measurements of gas temperature in an operating gasifier. Following the completion of the initial 3 year project, several continuations were awarded by the Department of Energy to allow Enertechnix to conduct extended testing of the sensor at the Wabash River facility. In February, 2008 the sensor was installed on the gasifier in preparation for a long-term test. During the initial testing of the sensor a stainless steel tube on the sensor failed and allowed syngas to escape. The syngas self-ignited and the ensuing small fire damaged some of the components on the sensor. There was no damage to the gasifier or other equipment and no injuries resulted from this incident. Two meetings were held to identify the root causes of the incident-one at Wabash River and one at Enertechnix. A list of recommended improvements that would have addressed the causes of the incident was created and presented to the Department of Energy on May 2, 2008. However, the DOE decided not to pursue these improvements and terminated the project. This report describes all of the activities conducted during the project and reports the findings of each activity in detail. The investigation of potential sound generation and coupling methods led to the selection of a reflected shock method which has been developed into a functioning prototype device. The principles of operation of this device and its performance characteristics are described in the report. Modeling of the attenuation of sound by suspended particles and by interaction of the sound pulses with the high temperature syngas inside the gasifier was conducted and the predictions of those models were used to determine the required sound pulse intensity to allow the sound pulses to be detected after passage through the gasifier environment. These modeling results are presented in this report. A study of the likely spatial and temporal variability of gas composition inside the gasifier was performed and the results of that study was used to predict the impact of that variability on the accuracy of the acoustic temperature method. These results are reported here. A design for a port rodding mechanism was developed to deal with potential slagging issues and was incorporated i

  5. Fiber-optic voltage sensor with cladded fiber and evanescent wave variation detection

    DOE Patents [OSTI]

    Wood, C.B.

    1992-12-15T23:59:59.000Z

    A fiber optic voltage sensor is described which includes a source of light, a reference fiber for receiving a known percentage of the light and an electrostrictive element having terminals across which is applied, a voltage to be measured. The electrostrictive element is responsive to the applied voltage to assume an altered physical state. A measuring fiber also receives a known percentage of light from the light source and is secured about the electrostrictive element. The measuring fiber is provided with a cladding and exhibits an evanescent wave in the cladding. The measuring fiber has a known length which is altered when the electrostrictive element assumes its altered physical state. A differential sensor is provided which senses the intensity of light in both the reference fiber and the measuring fiber and provides an output indicative of the difference between the intensities. 3 figs.

  6. Fiber-optic voltage sensor with cladded fiber and evanescent wave variation detection

    DOE Patents [OSTI]

    Wood, Charles B. (Lakewood, CO)

    1992-01-01T23:59:59.000Z

    A fiber optic voltage sensor is described which includes a source of light, a reference fiber for receiving a known percentage of the light and an electrostrictive element having terminals across which is applied, a voltage to be measured. The electrostrictive element is responsive to the applied voltage to assume an altered physical state. A measuring fiber also receives a known percentage of light from the light source and is secured about the electrostrictive element. The measuring fiber is provided with a cladding and exhibits an evanescent wave in the cladding. The measuring fiber has a known length which is altered when the electrostrictive element assumes its altered physical state. A differential sensor is provided which senses the intensity of light in both the reference fiber and the measuring fiber and provides an output indicative of the difference between the intensities.

  7. Optical Detection and Manipulation of Single Molecules in Room-Temperature Solutions

    E-Print Network [OSTI]

    Zare, Richard N.

    CONCEPTS Optical Detection and Manipulation of Single Molecules in Room-Temperature Solutions. Keywords: single-moleculedetection - single-moleculema- nipulation - laser-induced fluorescence * optical, frcquency-modulated optical ab- sorption and fluorescence excitation have been used to investi- gate

  8. Distributed fiber-optic temperature sensing for hydrologic systems John S. Selker,1,2

    E-Print Network [OSTI]

    Selker, John

    Distributed fiber-optic temperature sensing for hydrologic systems John S. Selker,1,2 Luc The; accepted 27 October 2006; published 6 December 2006. [1] Instruments for distributed fiber-optic m with temporal resolution of fractions of a minute along standard fiber-optic cables used

  9. Near-Field Scanning Optical Microscopy of Temperature-and Thickness-Dependent Morphology and

    E-Print Network [OSTI]

    Buratto, Steve

    Near-Field Scanning Optical Microscopy of Temperature- and Thickness-Dependent Morphology 21, 2000 We use near-field scanning optical microscopy (NSOM) to probe the local optical spectroscopy with bulk techniques such as differ- ential scanning calorimetry (DSC) and X-ray diffractom- etry

  10. Development Of An Acoustice Sensor For On-Line Gas Temperature Measurement In Gasifiers

    SciTech Connect (OSTI)

    Peter Ariessohn; Hans Hornung

    2006-10-01T23:59:59.000Z

    This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) Program Solicitation DE-PS26-02NT41422 and specifically addresses Technical Topical Area 2 - Gasification Technologies. The project team includes Enertechnix, Inc. as the main contractor and ConocoPhillips Company as a technical partner, who also provides access to the SG Solutions Gasification Facility (formerly Wabash River Energy Limited), host for the field-testing portion of the research. The objective of this project was to adapt acoustic pyrometer technology to make it suitable for measuring gas temperature inside a coal gasifier, to develop a prototype sensor based on this technology, and to demonstrate its performance through testing on a commercial gasifier. The project was organized in three phases, each of approximately one year duration. The first phase consisted of researching a variety of sound generation and coupling approaches suitable for use with a high pressure process, evaluation of the impact of gas composition variability on the acoustic temperature measurement approach, evaluation of the impact of suspended particles and gas properties on sound attenuation, evaluation of slagging issues and development of concepts to deal with this issue, development and testing of key prototype components to allow selection of the best approaches, and development of a conceptual design for a field prototype sensor that could be tested on an operating gasifier. The second phase consisted of designing and fabricating a series of prototype sensors, testing them in the laboratory, and developing a conceptual design for a field prototype sensor. The third phase consisted of designing and fabricating the field prototype, and testing it in the lab and in a commercial gasifier to demonstrate the ability to obtain accurate measurements of gas temperature in an operating gasifier. This report describes all of the activities conducted during the project and reports the findings of each activity in detail. The investigation of potential sound generation and coupling methods led to the selection of a reflected shock method which has been developed into a functioning prototype device. The principles of operation of this device and its performance characteristics are described in the report. Modeling of the attenuation of sound by suspended particles and by interaction of the sound pulses with the high temperature syngas inside the gasifier was conducted and the predictions of those models were used to determine the required sound pulse intensity to allow the sound pulses to be detected after passage through the gasifier environment. These modeling results are presented in this report. A study of the likely spatial and temporal variability of gas composition inside the gasifier was performed and the results of that study was used to predict the impact of that variability on the accuracy of the acoustic temperature method. These results are reported here. A design for a port rodding mechanism was developed to deal with potential slagging issues and was incorporated into the prototype sensor. This port rodding mechanism operated flawlessly during the field testing, but because these tests were performed in a region of the gasifier that experiences little slagging, the effectiveness of the rodding mechanism in dealing with highly slagging conditions was not fully demonstrated. This report describes the design and operation of the automated Gasifier Acoustic Pyrometer (autoGAP) which was tested at the Wabash River facility. The results of the tests are reported and analyzed in detail. All of the objectives of the project have been achieved. A field prototype acoustic pyrometer sensor has been successfully tested at the Wabash River gasifier plant. Acoustic signals were propagated through the gases inside the gasifier and were detected by the receiver unit, the times of flight of these sound pulses were measured and these propagation times were converted into temperatures which agreed very well with thermocouple measurements m

  11. QUALIFICATION OF A TRULY DISTRIBUTED FIBER OPTIC TECHNIQUE FOR STRAIN AND TEMPERATURE MEASUREMENTS IN CONCRETE STRUCTURES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ) and insensitive to electromagnetic fields. Thanks to the low attenuation of the transmitted light signal monitoring is a key factor in life cycle management of infrastructures. Truly distributed fiber optic sensors experiments seem very promising since measurements performed with distributed sensing systems are found

  12. Voltage sensor with fiber Fabry-Perot interferometer

    E-Print Network [OSTI]

    Wann, Been-Huey

    1992-01-01T23:59:59.000Z

    INTRODUCTION. Page II RESEARCH DESCRIPTION. . . A. Optical Fiber Fabry-Perot Interferometer. . . . . B. Piezoelectricity. . C. Modulating Point in 60 Hz Voltage Measurement. . . . . . D. Temperature Control Circuit . . . . 18 . . . 26 III EXPERIMENTAL... PROCEDURES AND RESULTS. . . . . . A. Fabrication of the Optical Fiber Fabry-Perot Interferometer B. Selection of Piezoelectric Materials. C. Implementation of Temperature Control Circuit. . . . D. Experiments of Optical Fiber Voltage Sensor...

  13. Detection of pico-Tesla magnetic fields using magneto-electric sensors at room temperature

    SciTech Connect (OSTI)

    Zhai Junyi; Xing Zengping; Dong Shuxiang; Li Jiefang; Viehland, D. [Department of Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2006-02-06T23:59:59.000Z

    The measurement of low-frequency (10{sup -2}-10{sup 3} Hz) minute magnetic field variations (10{sup -12} Tesla) at room temperature in a passive mode of operation would be critically enabling for deployable neurological signal interfacing and magnetic anomaly detection applications. However, there is presently no magnetic field sensor capable of meeting all of these requirements. Here, we present new bimorph and push-pull magneto-electric laminate composites, which incorporate a charge compensation mechanism (or bridge) that dramatically enhances noise rejection, enabling achievement of such requirements.

  14. Effect of Temperature and Charged Particle Fluence on the Resistivity of Polycrystalline CVD Diamond Sensors

    E-Print Network [OSTI]

    Rui Wang; Martin Hoeferkamp; Sally Seidel

    2013-10-09T23:59:59.000Z

    The resistivity of polycrystalline chemical vapor deposition diamond sensors is studied in samples exposed to fluences relevant to the environment of the High Luminosity Large Hadron Collider. We measure the leakage current for a range of bias voltages on samples irradiated with 800 MeV protons up to 1.6\\times 10^{16} p/cm^2. The proton beam at LANSCE, Los Alamos National Laboratory, was applied to irradiate the samples. The devices' resistivity is extracted for temperatures in the -10^\\circC to +20^\\circC range.

  15. Effect of Temperature and Charged Particle Fluence on the Resistivity of Polycrystalline CVD Diamond Sensors

    E-Print Network [OSTI]

    Wang, Rui; Seidel, Sally

    2013-01-01T23:59:59.000Z

    The resistivity of polycrystalline chemical vapor deposition diamond sensors is studied in samples exposed to fluences relevant to the environment of the High Luminosity Large Hadron Collider. We measure the leakage current for a range of bias voltages on samples irradiated with 800 MeV protons up to 1.6\\times 10^{16} p/cm^2. The proton beam at LANSCE, Los Alamos National Laboratory, was applied to irradiate the samples. The devices' resistivity is extracted for temperatures in the -10^\\circC to +20^\\circC range.

  16. An investigation of sea surface temperature patterns in the Gulf of Mexico as determined by an airborne infrared sensor

    E-Print Network [OSTI]

    Drennan, Kirby Lee

    1967-01-01T23:59:59.000Z

    AN INVESTIGATION OF SEA SURFACE TF"PERATURE PATTERNS IN THE GULF OF IKXICO AS DETERMINED BY AN AIRBORNE INFRARED SENSOR A Thesis by KIRBY IEE DRENNAN Submitted to the Graduate College of the Texas API University in partial tulfillment... of the requirements for the degree of 14IASTER OF SCIENCE August 1967 Physical Oceanography AN INVESTIGATION OF SEA SURFACE TEMPERATURE PATIERNS IN THE GULF OF MEXICO AS DETERMINED BY AN AIRBORNE INFRARED SENSOR A Thesis by KIRBY LEE DRENNAN Approved...

  17. Pt silicide/poly-Si Schottky diodes as temperature sensors for bolometers

    E-Print Network [OSTI]

    Yuryev, V A; Chapnin, V A; Mironov, S A; Dubkov, V P; Uvarov, O V; Kalinushkin, V P; Senkov, V M; Nalivaiko, O Y; Novikau, A G; Gaiduk, P I

    2015-01-01T23:59:59.000Z

    Platinum silicide Schottky diodes formed on films of polycrystalline Si doped by phosphorus are demonstrated to be efficient and manufacturable CMOS-compatible temperature sensors for microbolometer detectors of radiation. Thin-film platinum silicide/poly-Si diodes have been produced by a CMOS-compatible process on artificial Si$_3$N$_4$/SiO$_2$/Si(001) substrates simulating the bolometer cells. Layer structure and phase composition of the original Pt/poly-Si films and the Pt silicide/poly-Si films synthesized by a low-temperature process have been studied by means of the scanning transmission electron microscopy; they have also been explored by means of the two-wavelength X-ray structural phase analysis and the X-ray photoelectron spectroscopy. Temperature coefficient of voltage for the forward current of a single diode is shown to reach the value of about $-$2%/$^{\\circ}$C in the temperature interval from 25 to 50$^{\\circ}$C.

  18. Optical gain and lasing from band-engineered Ge-on-Si at room temperature

    E-Print Network [OSTI]

    Liu, Jifeng

    We present theoretical modeling and experimental results of optical gain and lasing from tensile-strained, n[superscript +] Ge-on-Si at room temperature. Compatible with silicon CMOS, these devices are ideal for large-scale ...

  19. Optical-Engine Study of a Low-Temperature Combustion Strategy...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Study of a Low-Temperature Combustion Strategy Employing a Dual-Row, Narrow-Included-Angle Nozzle and Early, Direct Injection of Diesel Fuel Optical-Engine Study of a...

  20. Spark-plug-mounted fiber optic sensor for measuring in-cylinder pressure in engines 

    E-Print Network [OSTI]

    Bae, Taehan

    2001-01-01T23:59:59.000Z

    , with an optoelectronic signal conditioning unit containing a chirped distributed feedback laser used to interrogate the sensor. The response of the fiber sensor was compared with that of a piezoelectric pressure sensor used as a reference transducer. Tests were carried...

  1. Detecting high-frequency gravitational waves with optically-levitated sensors

    E-Print Network [OSTI]

    Asimina Arvanitaki; Andrew A. Geraci

    2013-01-02T23:59:59.000Z

    We propose a tunable resonant sensor to detect gravitational waves in the frequency range of 50-300 kHz using optically trapped and cooled dielectric microspheres or micro-discs. The technique we describe can exceed the sensitivity of laser-based gravitational wave observatories in this frequency range, using an instrument of only a few percent of their size. Such a device extends the search volume for gravitational wave sources above 100 kHz by 1 to 3 orders of magnitude, and could detect monochromatic gravitational radiation from the annihilation of QCD axions in the cloud they form around stellar mass black holes within our galaxy due to the superradiance effect.

  2. Temperature inversion on the surface of externally heated optically thick multigrain dust clouds

    E-Print Network [OSTI]

    Dejan Vinkovic

    2006-12-01T23:59:59.000Z

    It was recently discovered that the temperature in the surface layer of externally heated optically thick gray dust clouds increases with the optical depth for some distance from the surface, as opposed to the normal decrease in temperature with distance in the rest of the cloud. This temperature inversion is a result of efficient absorption of diffuse flux from the cloud interior by the surface dust exposed to the external radiation. A micron or bigger size grains experience this effect when the external flux is of stellar spectrum. We explore what happens to the effect when dust is a mixture of grain sizes (multigrain). Two possible boundary conditions are considered: i) a constant external flux without constrains on the dust temperature, and ii) the maximum dust temperature set to the sublimation temperature. We find that the first condition allows small grains to completely suppress the temperature inversion of big grains if the overall opacity is dominated by small grains. The second condition enables big grains to maintain the inversion even when they are a minor contributor to the opacity. In reality, the choice of boundary condition depends on the dust dynamics. When applied to the physics of protoplanetary disks, the temperature inversion leads to a previously unrecognized disk structure where optically thin dust can exist inside the dust destruction radius of an optically thick disk. We conclude that the transition between the dusty disk and the gaseous inner clearing is not a sharp edge, but rather a large optically thin region.

  3. Optical gain from the direct gap transition of Ge-on-Si at room temperature

    E-Print Network [OSTI]

    Liu, Jifeng

    We report direct band gap optical gain of tensile strained n+ epitaxial Ge-on-Si at room temperature, which confirms that band-engineered Ge-on-Si is a promising gain medium for monolithic optical amplifiers and lasers on Si.

  4. Organic light emitting diodes (OLEDS) and OLED-based structurally integrated optical sensors

    SciTech Connect (OSTI)

    Cai, Yuankun

    2010-05-16T23:59:59.000Z

    General introduction to OLED basics and OLED-based structurally integrated sensors was provided in chapter 1 and chapter 2. As discussed in chapter 3, OLEDs were developed or improved using novel engineering methods for better charge injection (increased by over 1 order of magnitude) and efficiency. As the excitation sources, these OLEDs have preferred characteristics for sensor applications, including narrowed emission, emission at desired wavelength, and enhanced output for reduced EL background, higher absorption and improved device lifetime. In addition to OLEDs with desired performance, sensor integration requires oxidase immobilization with the sensor film for O{sub 2}-based biological and chemical sensing. Nanoparticles such as ZnO have large surface area and high isoelectric point ({approx}9.5), which favors enzyme immobilization via physical adsorption as well as Coulombic bonding. In chapter 4, it was demonstrated that ZnO could be used for this purpose, although future work is needed to further bond the ZnO to the sensor film. In chapter 5, single unit sensor was extended to multianalyte parallel sensing based on an OLED platform, which is compact and integrated with silicon photodiodes and electronics. Lactate and glucose were simultaneously monitored with a low limit of detection 0.02 mM, fast response time ({approx} 1 minute) and dynamic range from 0-8.6 ppm of dissolved oxygen. As discovered in previous work, the dynamic range covers 0-100% gas phase O{sub 2} or 0-40 ppm dissolved oxygen at room temperature. PL decay curve, which is used to extract the decay time, is usually not a simple exponential at high O{sub 2} concentration, which indicates that O{sub 2} is not equally accessible for different luminescent sites. This creates a challenge for data analysis, which however was successfully processed by stretched exponential as shown in chapter 6. This also provides an insight about the distribution of O{sub 2}:dye collisional quenching rate due to microheterogeneity. Effect of TiO{sub 2} doping was also discussed. Stretched exponential analysis also generates calibration curves with higher sensitivity, which is preferred from the operational point of view. The work of enhanced integration was shown in chapter 7 with a polymer photodetector, which enables the preferred operation mode, decay time measurement, due to fast reponse (<20 {mu}s). Device thickness was enlarged for maximum absorption of the PL, which was realized by slow spincoating rate and shorter spincoating time. Film prepared this way shows more crystalline order by Raman spectra, probably due to slow evaporation. This also ensures charge transport is not affected even with a thick film as indicated in the response time. Combination of OLEDs and polymer photodetectors present opportunities for solution processed all-organic sensors, which enables cheap processing at large scale. Future development can focus on monolithically integration of OLEDs and organic photodetectors (OPD) on the same substrate at a small scale, which could be enabled by inkjet printing. As OLED and OPD technologies continue to advance, small-sized, flexible and all-organic structurally integrated sensor platforms will become true in the near future.

  5. Robust high temperature composite and CO sensor made from such composite

    DOE Patents [OSTI]

    Dutta, Prabir K.; Ramasamy, Ramamoorthy; Li, Xiaogan; Akbar, Sheikh A.

    2010-04-13T23:59:59.000Z

    Described herein is a composite exhibiting a change in electrical resistance proportional to the concentration of a reducing gas present in a gas mixture, detector and sensor devices comprising the composite, a method for making the composite and for making devices comprising the composite, and a process for detecting and measuring a reducing gas in an atmosphere. In particular, the reducing gas may be carbon monoxide and the composite may comprise rutile-phase TiO2 particles and platinum nanoclusters. The composite, upon exposure to a gas mixture containing CO in concentrations of up to 10,000 ppm, exhibits an electrical resistance proportional to the concentration of the CO present. The composite is useful for making sensitive, low drift, fast recovering detectors and sensors, and for measuring CO concentrations in a gas mixture present at levels from sub-ppm up to 10,000 ppm. The composites, and devices made from the composites, are stable and operable in a temperature range of from about 450.degree. C. to about 700.degree. C., such as may be found in a combustion chamber.

  6. GFOC Project results: High Temperature / High Pressure, Hydrogen Tolerant Optical Fiber

    SciTech Connect (OSTI)

    E. Burov; A. Pastouret; E. Aldea; B. Overton; F. Gooijer; A. Bergonzo

    2012-02-12T23:59:59.000Z

    Tests results are given for exposure of multimode optical fiber to high temperatures (300 deg. C) and high partial pressure (15 bar) hydrogen. These results demonstrate that fluorine down doped optical fibers are much more hydrogen tolerant than traditional germanium doped multimode optical fibers. Also demonstrated is the similar hydrogen tolerance of carbon coated and non-carbon coated fibers. Model for reversible H2 impact in fiber versus T{sup o}C and H2 pressure is given. These results have significant impact for the longevity of use for distributed temperature sensing applications in harsh environments such as geothermal wells.

  7. Temperature-insensitive phase-matched optical harmonic conversion crystal

    DOE Patents [OSTI]

    Barker, C.E.; Eimerl, D.; Velsko, S.P.; Roberts, D.

    1993-11-23T23:59:59.000Z

    Temperature-insensitive, phase-matched harmonic frequency conversion of laser light at a preferred wavelength of 1.064 microns can be achieved by use of a crystal of deuterated l-arginine phosphate. The crystal is cut and oriented so that the laser light propagates inside the crystal along one of several required directions, which correspond to a temperature-insensitive, phase-matching locus. The method of measuring and calculating the temperature-insensitive, phase-matching angles can be extended to other fundamental wavelengths and other crystal compositions. 12 figures.

  8. Temperature-insensitive phase-matched optical harmonic conversion crystal

    DOE Patents [OSTI]

    Barker, Charles E. (Sunnyvale, CA); Eimerl, David (Livermore, CA); Velsko, Stephan P. (Livermore, CA); Roberts, David (Sagamore Hills, OH)

    1993-01-01T23:59:59.000Z

    Temperature-insensitive, phase-matched harmomic frequency conversion of laser light at a preferred wavelength of 1.064 microns can be achieved by use of a crystal of deuterated l-arginine phosphate. The crystal is cut and oriented so that the laser light propagates inside the crystal along one of several required directions, which correspond to a temperature-insensitive, phase-matching locus. The method of measuring and calculating the temperature-insensitive, phase-matching angles can be extended to other fundamental wavelengths and other crystal compositions.

  9. Exciton-Phonon coupling in the finite temperature optical absorption of

    E-Print Network [OSTI]

    Marini, Andrea

    and absorption spectra PRL 95, 247401 (2005) PRB 36, 4821 (1987) Phonons are responsible for the temperature temperature optics in the polaronic approximation A phononic self-energy for the exciton #12;PRB 23, 1495 (1981)LH and SL, Solid. State Phys. 23, 1 (1969); RvL, PRB 69, 115110 (2004) I Is Cardona-Allen further

  10. Experimental setup for investigation of nanoclusters at cryogenic temperatures by electron spin resonance and optical spectroscopies

    SciTech Connect (OSTI)

    Mao, S., E-mail: maoshunghost@tamu.edu; Meraki, A.; McColgan, P. T.; Khmelenko, V. V.; Lee, D. M. [Institute for Quantum Science and Engineering and Department of Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States); Shemelin, V. [Cornell Laboratory for Accelerator-based Science and Education, Cornell University, Ithaca, New York 14853 (United States)

    2014-07-15T23:59:59.000Z

    We present the design and performance of an experimental setup for simultaneous electron spin resonance (ESR) and optical studies of nanoclusters with stabilized free radicals at cryogenic temperatures. A gas mixture of impurities and helium after passing through a RF discharge for dissociation of molecules is directed onto the surface of superfluid helium to form the nanoclusters of impurities. A specially designed ESR cavity operated in the TE{sub 011} mode allows optical access to the sample. The cavity is incorporated into a homemade insert which is placed inside a variable temperature insert of a Janis {sup 4}He cryostat. The temperature range for sample investigation is 1.25–300 K. A Bruker EPR 300E and Andor 500i optical spectrograph incorporated with a Newton EMCCD camera are used for ESR and optical registration, respectively. The current experimental system makes it possible to study the ESR and optical spectra of impurity-helium condensates simultaneously. The setup allows a broad range of research at low temperatures including optically detected magnetic resonance, studies of chemical processes of the active species produced by photolysis in solid matrices, and investigations of nanoclusters produced by laser ablation in superfluid helium.

  11. High-sensitivity optical monitoring of a micro-mechanical resonator with a quantum-limited optomechanical sensor

    E-Print Network [OSTI]

    O. Arcizet; P. -F. Cohadon; T. Briant; M. Pinard; A. Heidmann; J. -M. Mackowski; C. Michel; L. Pinard; O. Francais; L. Rousseau

    2006-05-19T23:59:59.000Z

    We experimentally demonstrate the high-sensitivity optical monitoring of a micro-mechanical resonator and its cooling by active control. Coating a low-loss mirror upon the resonator, we have built an optomechanical sensor based on a very high-finesse cavity (30000). We have measured the thermal noise of the resonator with a quantum-limited sensitivity at the 10^-19 m/rootHz level, and cooled the resonator down to 5K by a cold-damping technique. Applications of our setup range from quantum optics experiments to the experimental demonstration of the quantum ground state of a macroscopic mechanical resonator.

  12. A diamond-based scanning probe spin sensor operating at low temperature in ultra-high vacuum

    SciTech Connect (OSTI)

    Schaefer-Nolte, E.; Wrachtrup, J. [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany) [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany); 3rd Institute of Physics and Research Center SCoPE, University Stuttgart, 70569 Stuttgart (Germany); Reinhard, F. [3rd Institute of Physics and Research Center SCoPE, University Stuttgart, 70569 Stuttgart (Germany)] [3rd Institute of Physics and Research Center SCoPE, University Stuttgart, 70569 Stuttgart (Germany); Ternes, M., E-mail: m.ternes@fkf.mpg.de [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany); Kern, K. [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany) [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany); Institut de Physique de la Matière Condenseé, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne (Switzerland)

    2014-01-15T23:59:59.000Z

    We present the design and performance of an ultra-high vacuum (UHV) low temperature scanning probe microscope employing the nitrogen-vacancy color center in diamond as an ultrasensitive magnetic field sensor. Using this center as an atomic-size scanning probe has enabled imaging of nanoscale magnetic fields and single spins under ambient conditions. In this article we describe an experimental setup to operate this sensor in a cryogenic UHV environment. This will extend the applicability to a variety of molecular systems due to the enhanced target spin lifetimes at low temperature and the controlled sample preparation under UHV conditions. The instrument combines a tuning-fork based atomic force microscope (AFM) with a high numeric aperture confocal microscope and the facilities for application of radio-frequency (RF) fields for spin manipulation. We verify a sample temperature of <50 K even for strong laser and RF excitation and demonstrate magnetic resonance imaging with a magnetic AFM tip.

  13. Acoustic Source Localization via Time Difference of Arrival Estimation for Distributed Sensor Networks Using Tera-Scale Optical Core Devices

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Imam, Neena; Barhen, Jacob

    2009-01-01T23:59:59.000Z

    For real-time acoustic source localization applications, one of the primary challenges is the considerable growth in computational complexity associated with the emergence of ever larger, active or passive, distributed sensor networks. These sensors rely heavily on battery-operated system components to achieve highly functional automation in signal and information processing. In order to keep communication requirements minimal, it is desirable to perform as much processing on the receiver platforms as possible. However, the complexity of the calculations needed to achieve accurate source localization increases dramatically with the size of sensor arrays, resulting in substantial growth of computational requirements that cannot bemore »readily met with standard hardware. One option to meet this challenge builds upon the emergence of digital optical-core devices. The objective of this work was to explore the implementation of key building block algorithms used in underwater source localization on the optical-core digital processing platform recently introduced by Lenslet Inc. This demonstration of considerably faster signal processing capability should be of substantial significance to the design and innovation of future generations of distributed sensor networks.« less

  14. Spark-plug-mounted fiber optic sensor for measuring in-cylinder pressure in engines

    E-Print Network [OSTI]

    Bae, Taehan

    2001-01-01T23:59:59.000Z

    A new design for an in-cylinder fiber Fabry-Perot interferometer (FFPI) pressure sensor suitable for automotive engines has been investigated experimentally. The FFPI sensor consists of a single mode fiber containing two internal mirrors which form...

  15. Negative ion source with low temperature transverse divergence optical system

    DOE Patents [OSTI]

    Whealton, J.H.; Stirling, W.L.

    1985-03-04T23:59:59.000Z

    A negative ion source is provided which has extremely low transverse divergence as a result of a unique ion focusing system in which the focal line of an ion beam emanating from an elongated, concave converter surface is outside of the ion exit slit of the source and the path of the exiting ions. The beam source operates with a minimum ion temperature which makes possible a sharply focused (extremely low transverse divergence) ribbon like negative ion beam.

  16. Negative ion source with low temperature transverse divergence optical system

    DOE Patents [OSTI]

    Whealton, John H. (Oak Ridge, TN); Stirling, William L. (Oak Ridge, TN)

    1986-01-01T23:59:59.000Z

    A negative ion source is provided which has extremely low transverse divergence as a result of a unique ion focusing system in which the focal line of an ion beam emanating from an elongated, concave converter surface is outside of the ion exit slit of the source and the path of the exiting ions. The beam source operates with a minimum ion temperature which makes possible a sharply focused (extremely low transverse divergence) ribbon like negative ion beam.

  17. Short-wavelength upconversion emissions in codoped glass ceramic and the optical

    E-Print Network [OSTI]

    Cao, Wenwu

    of electrical engineering, Yanshan University, Qinhuangdao, 066004, China 3 Laboratory of Sono- and photo. In addition, an optical temperature sensor based on the blue upconversion emissions from 5 F2,3/3 K85 I8 and 5 ceramic be a promising candidate for sensitive optical temperature sensor with high resolution and good

  18. Performance of miniaturized optical fiber interconnects between sensor-embedded composite panels

    E-Print Network [OSTI]

    Miller, Ethan L.

    the performance of low-profile multi-fiber connectors between sensor- embedded composite panels and Sensor Technologies P.O. Box 11704 Blacksburg, VA 24061-1704, (703) 231-4224 ABSTRACT This paper reports to locally weaken the material and to expose the fiber sensor channel to the external environment. We report

  19. Optical sensing elements for nitrogen dioxide (NO.sub.2) gas detection, a sol-gel method for making the sensing elements and fiber optic sensors incorporating nitrogen dioxide gas optical sensing elements

    DOE Patents [OSTI]

    Mechery, Shelly John (Mississippi State, MS); Singh, Jagdish P. (Starkville, MS)

    2007-07-03T23:59:59.000Z

    A sensing element, a method of making a sensing element, and a fiber optic sensor incorporating the sensing element are described. The sensor can be used for the quantitative detection of NO.sub.2 in a mixture of gases. The sensing element can be made by incorporating a diazotizing reagent which reacts with nitrous ions to produce a diazo compound and a coupling reagent which couples with the diazo compound to produce an azo dye into a sol and allowing the sol to form an optically transparent gel. The sensing element changes color in the presence of NO.sub.2 gas. The temporal response of the absorption spectrum at various NO.sub.2 concentrations has also been recorded and analyzed. Sensors having different design configurations are described. The sensing element can detect NO.sub.2 gas at levels of parts per billion.

  20. Long-Term, Autonomous Measurement of Atmospheric Carbon Dioxide Using an Ormosil Nanocomposite-Based Optical Sensor

    SciTech Connect (OSTI)

    Kisholoy Goswami

    2005-10-11T23:59:59.000Z

    The goal of this project is to construct a prototype carbon dioxide sensor that can be commercialized to offer a low-cost, autonomous instrument for long-term, unattended measurements. Currently, a cost-effective CO2 sensor system is not available that can perform cross-platform measurements (ground-based or airborne platforms such as balloon and unmanned aerial vehicle (UAV)) for understanding the carbon sequestration phenomenon. The CO2 sensor would support the research objectives of DOE-sponsored programs such as AmeriFlux and the North American Carbon Program (NACP). Global energy consumption is projected to rise 60% over the next 20 years and use of oil is projected to increase by approximately 40%. The combustion of coal, oil, and natural gas has increased carbon emissions globally from 1.6 billion tons in 1950 to 6.3 billion tons in 2000. This figure is expected to reach 10 billon tons by 2020. It is important to understand the fate of this excess CO2 in the global carbon cycle. The overall goal of the project is to develop an accurate and reliable optical sensor for monitoring carbon dioxide autonomously at least for one year at a point remote from the actual CO2 release site. In Phase I of this project, InnoSense LLC (ISL) demonstrated the feasibility of an ormosil-monolith based Autonomous Sensor for Atmospheric CO2 (ASAC) device. All of the Phase I objectives were successfully met.

  1. Embedded Fiber Optic Sensors for Measuring Transient Detonation/Shock Behavior;Time-of-Arrival Detection and Waveform Determination.

    SciTech Connect (OSTI)

    Chavez, Marcus Alexander; Willis, Michael David; Covert, Timothy T.

    2014-09-01T23:59:59.000Z

    The miniaturization of explosive components has driven the need for a corresponding miniaturization of the current diagnostic techniques available to measure the explosive phenomena. Laser interferometry and the use of spectrally coated optical windows have proven to be an essential interrogation technique to acquire particle velocity time history data in one- dimensional gas gun and relatively large-scale explosive experiments. A new diagnostic technique described herein allows for experimental measurement of apparent particle velocity time histories in microscale explosive configurations and can be applied to shocks/non-shocks in inert materials. The diagnostic, Embedded Fiber Optic Sensors (EFOS), has been tested in challenging microscopic experimental configurations that give confidence in the technique's ability to measure the apparent particle velocity time histories of an explosive with pressure outputs in the tenths of kilobars to several kilobars. Embedded Fiber Optic Sensors also allow for several measurements to be acquired in a single experiment because they are microscopic, thus reducing the number of experiments necessary. The future of EFOS technology will focus on further miniaturization, material selection appropriate for the operating pressure regime, and extensive hydrocode and optical analysis to transform apparent particle velocity time histories into true particle velocity time histories as well as the more meaningful pressure time histories.

  2. Optics & Laser Technology 40 (2008) 625631 Three-dimensional non-destructive optical evaluation

    E-Print Network [OSTI]

    Chen, Zhongping

    2008-01-01T23:59:59.000Z

    . A pyrometer, an infrared radiation sensor, is used to monitor surface temperature variation in laser brazingOptics & Laser Technology 40 (2008) 625­631 Three-dimensional non-destructive optical evaluation of laser-processing performance using optical coherence tomography Youngseop Kima , Eun Seo Choia

  3. Planar optical waveguide based sandwich assay sensors and processes for the detection of biological targets including early detection of cancers

    DOE Patents [OSTI]

    Martinez, Jennifer S. (Santa Fe, NM); Swanson, Basil I. (Los Alamos, NM); Shively, John E. (Arcadia, CA); Li, Lin (Monrovia, CA)

    2009-06-02T23:59:59.000Z

    An assay element is described including recognition ligands adapted for binding to carcinoembryonic antigen (CEA) bound to a film on a single mode planar optical waveguide, the film from the group of a membrane, a polymerized bilayer membrane, and a self-assembled monolayer containing polyethylene glycol or polypropylene glycol groups therein and an assay process for detecting the presence of CEA is described including injecting a possible CEA-containing sample into a sensor cell including the assay element, maintaining the sample within the sensor cell for time sufficient for binding to occur between CEA present within the sample and the recognition ligands, injecting a solution including a reporter ligand into the sensor cell; and, interrogating the sample within the sensor cell with excitation light from the waveguide, the excitation light provided by an evanescent field of the single mode penetrating into the biological target-containing sample to a distance of less than about 200 nanometers from the waveguide thereby exciting any bound reporter ligand within a distance of less than about 200 nanometers from the waveguide and resulting in a detectable signal.

  4. Comparison of the high temperature heat flux sensor to traditional heat flux gages under high heat flux conditions.

    SciTech Connect (OSTI)

    Blanchat, Thomas K.; Hanks, Charles R.

    2013-04-01T23:59:59.000Z

    Four types of heat flux gages (Gardon, Schmidt-Boelter, Directional Flame Temperature, and High Temperature Heat Flux Sensor) were assessed and compared under flux conditions ranging between 100-1000 kW/m2, such as those seen in hydrocarbon fire or propellant fire conditions. Short duration step and pulse boundary conditions were imposed using a six-panel cylindrical array of high-temperature tungsten lamps. Overall, agreement between all gages was acceptable for the pulse tests and also for the step tests. However, repeated tests with the HTHFS with relatively long durations at temperatures approaching 1000%C2%B0C showed a substantial decrease (10-25%) in heat flux subsequent to the initial test, likely due to the mounting technique. New HTHFS gages have been ordered to allow additional tests to determine the cause of the flux reduction.

  5. Fiber Optic Based Thermometry System for Superconducting RF Cavities

    SciTech Connect (OSTI)

    Dr. Kochergin, Vladimir [Microxact Inc.] [Microxact Inc.

    2013-05-06T23:59:59.000Z

    Thermometry is recognized as the best technique to identify and characterize losses in SRF cavities. The most widely used and reliable apparatus for temperature mapping at cryogenic temperatures is based on carbon resistors (RTDs). The use of this technology on multi-cell cavities is inconvenient due to the very large number of sensors required to obtain sufficient spatial resolution. Recent developments make feasible the use of multiplexible fiber optic sensors for highly distributed temperature measurements. However, sensitivity of multiplexible cryogenic temperature sensors was found extending only to 12K at best and thus was not sufficient for SRF cavity thermometry. During the course of the project the team of MicroXact, JLab and Virginia Tech developed and demonstrated the multiplexible fiber optic sensor with adequate response below 20K. The demonstrated temperature resolution is by at least a factor of 60 better than that of the best multiplexible fiber optic temperature sensors reported to date. The clear path toward at least 10times better temperature resolution is shown. The first to date temperature distribution measurements with ~2.5mm spatial resolution was done with fiber optic sensors at 2K to4K temperatures. The repeatability and accuracy of the sensors were verified only at 183K, but at this temperature both parameters significantly exceeded the state of the art. The results of this work are expected to find a wide range of applications, since the results are enabling the whole new testing capabilities, not accessible before.

  6. Temperature-driven band inversion in Pb?.??Sn?.??Se: Optical and Hall-effect studies

    SciTech Connect (OSTI)

    Anand, Naween [Univ. of Florida, Gainesville, FL (United States); Gu, Genda [Brookhaven National Lab. (BNL), Upton, NY (United States); Buvaev, Sanal [Univ. of Florida, Gainesville, FL (United States); Hebard, A. F. [Univ. of Florida, Gainesville, FL (United States); Tanner, D. B. [Univ. of Florida, Gainesville, FL (United States); Chen, Zhiguo [Florida State Univ., Tallahassee, FL (United States); Li, Zhiqiang [Florida State Univ., Tallahassee, FL (United States); Choudhary, Kamal [Univ. of Florida, Gainesville, FL (United States); Sinnott, S. B. [Univ. of Florida, Gainesville, FL (United States); Martin, C. [Ramapo College, Mahwah, NJ (United States)

    2014-12-01T23:59:59.000Z

    Optical and Hall-effect measurements have been performed on single crystals of Pb?.??Sn?.??Se, a IV-VI mixed chalcogenide. The temperature dependent (10–300 K) reflectance was measured over 40–7000 cm?¹ (5–870 meV) with an extension to 15,500 cm?¹ (1.92 eV) at room temperature. The reflectance was fit to the Drude-Lorentz model using a single Drude component and several Lorentz oscillators. The optical properties at the measured temperatures were estimated via Kramers-Kronig analysis as well as by the Drude-Lorentz fit. The carriers were p-type with the carrier density determined by Hall measurements. A signature of valence intraband transition is found in the low-energy optical spectra. It is found that the valence-conduction band transition energy as well as the free carrier effective mass reach minimum values at 100 K, suggesting temperature-driven band inversion in the material. Density function theory calculation for the electronic band structure also make similar predictions.

  7. New Sensors for In-Pile Temperature Measurement at the Advanced Test Reactor National Scientific User Facility

    SciTech Connect (OSTI)

    J. L. Rempe; D. L. Knudson; J. E. Daw; K. G. Condie

    2011-09-01T23:59:59.000Z

    The U.S. Department of Energy (DOE) designated the Advanced Test Reactor (ATR) a National Scientific User Facility (NSUF) in April 2007 to support U.S. research in nuclear science and technology. As a user facility, the ATR is supporting new users from universities, laboratories, and industry, as they conduct basic and applied nuclear research and development to advance the nation’s energy security needs. A key component of the ATR NSUF effort is to develop and evaluate new in-pile instrumentation techniques that are capable of providing measurements of key parameters during irradiation. This paper describes the strategy for determining what instrumentation is needed and the program for developing new or enhanced sensors that can address these needs. Accomplishments from this program are illustrated by describing new sensors now available and under development for in-pile detection of temperature at various irradiation locations in the ATR.

  8. New Sensors for In-Pile Temperature Detection at the Advanced Test Reactor National Scientific User Facility

    SciTech Connect (OSTI)

    J. L. Rempe; D. L. Knudson; J. E. Daw; K. G. Condie; S. Curtis Wilkins

    2009-09-01T23:59:59.000Z

    The Department of Energy (DOE) designated the Advanced Test Reactor (ATR) as a National Scientific User Facility (NSUF) in April 2007 to support U.S. leadership in nuclear science and technology. As a user facility, the ATR is supporting new users from universities, laboratories, and industry, as they conduct basic and applied nuclear research and development to advance the nation’s energy security needs. A key component of the ATR NSUF effort is to develop and evaluate new in-pile instrumentation techniques that are capable of providing measurements of key parameters during irradiation. This paper describes the strategy for determining what instrumentation is needed and the program for developing new or enhanced sensors that can address these needs. Accomplishments from this program are illustrated by describing new sensors now available and under development for in-pile detection of temperature at various irradiation locations in the ATR.

  9. Investigation of Temperature Dependent Optical Modes in GexAs35-xSe65 Thin Films: Structure Specific Raman, FIR and Optical Absorption Spectroscopy

    E-Print Network [OSTI]

    Khan, Pritam; Joshy, Abin; Sathe, Vasant; Deshpande, Uday; Adarsh, K V

    2015-01-01T23:59:59.000Z

    In this article, we present a comprehensive study of temperature and composition dependent Raman spectroscopy of GexAs35-xSe65 thin films to understand different structural units responsible for optical properties. Strikingly, our experimental results uncover the ratio of GeSe4/2 tetrahedral and AsSe3/2 pyramidal units in GexAs35-xSe65 thin films and their linear scaling relationship with temperature and x. An important notable outcome of our study is the formation of Se8 rings at lower temperatures. Our experimental results further provide interesting optical features, thermally and compositionally tunable optical absorption spectra. Detailed structure specific FIR data at room temperature also present direct information on the structural units in consistent with Raman data. We foresee that our studies are useful in determining the lightinduced response of these films and also for their potential applications in optics and optoelectronics.

  10. Design and fabrication of an optical pressure micro sensor for skin mechanics studies

    E-Print Network [OSTI]

    Kumar, Siddarth

    2006-01-01T23:59:59.000Z

    The mechanics of skin is as central to touch as optics is to vision and acoustics is to hearing. With the advent of novel imaging technologies such as the Optical Coherence Tomography (OCT), we are now able to view structures ...

  11. Electric field sensor based on electro-optic polymer refilled silicon slot photonic crystal waveguide coupled with bowtie antenna

    E-Print Network [OSTI]

    Zhang, Xingyu; Xu, Xiaochuan; Wang, Shiyi; Zhan, Qiwen; Zou, Yi; Chakravarty, Swapnajit; Chen, Ray T

    2014-01-01T23:59:59.000Z

    We present the design of a compact and highly sensitive electric field sensor based on a bowtie antenna-coupled slot photonic crystal waveguide (PCW). An electro-optic (EO) polymer with a large EO coefficient, r33=100pm/V, is used to refill the PCW slot and air holes. Bowtie-shaped electrodes are used as both poling electrodes and as receiving antenna. The slow-light effect in the PCW is used to increase the effective in-device r33>1000pm/V. The slot PCW is designed for low-dispersion slow light propagation, maximum poling efficiency as well as optical mode confinement inside the EO polymer. The antenna is designed for operation at 10GHz.

  12. Anomalous Fiber Optic Gyroscope Signals Observed above Spinning Rings at Low Temperature

    E-Print Network [OSTI]

    M. Tajmar; F. Plesescu; B. Seifert

    2008-06-25T23:59:59.000Z

    Precision fiber optic gyroscopes were mounted mechanically de-coupled above spinning rings inside a cryostat. Below a critical temperature (typically <30 K), the gyroscopes measure a significant deviation from their usual offset due to Earth's rotation. This deviation is proportional to the applied angular ring velocity with maximum signals towards lower temperatures. The anomalous gyroscope signal is about 8 orders of magnitude smaller then the applied angular ring velocity, compensating about one third of the Earth rotation offset at an angular top speed of 420 rad/s. Moreover, our data shows a parity violation as the effect appears to be dominant for rotation against the Earth's spin. No systematic effect was found to explain this effect including the magnetic environment, vibration and helium gas friction suggesting that our observation is a new low temperature phenomenon. Tests in various configurations suggest that the rotating low temperature helium may be the source of our anomalous signals.

  13. An optical fiber Faraday effect current sensor for power system applications 

    E-Print Network [OSTI]

    Short, Shayne Xavier

    1995-01-01T23:59:59.000Z

    is compared to a high performance, commercially available, instrumentation current transducer. Specifically, the responses of the two sensors are compared in real time during various operating conditions. Concurrently, a theoretical analysis of the test...

  14. Application and modeling of frequency-domain lifetime spectroscopy for microsphere-based optical glucose sensors 

    E-Print Network [OSTI]

    Liang, Feng

    2009-05-15T23:59:59.000Z

    A new glucose affinity sensor based on a homogeneous fluorescence resonance energy transfer (FRET) assay system was developed to monitor the competitive binding between concanavalin A (ConA) and dextran. The FRET quenching kinetics of the donor were...

  15. Utilizing Distributed Temperature Sensors in Predicting Flow Rates in Multilateral Wells 

    E-Print Network [OSTI]

    Al Mulla, Jassim Mohammed A.

    2012-07-16T23:59:59.000Z

    gradient. Thus the need of accurate and high precision gauges becomes critical. The trade-off of high resolution sensors is the related cost and resulting complication in modeling. Interpreting measured data at real-time to a downhole flow profile...

  16. Blue-phase-polymer-templated nematic with sub-millisecond broad-temperature range electro-optic switching

    E-Print Network [OSTI]

    Jie Xiang; Oleg D. Lavrentovich

    2013-07-31T23:59:59.000Z

    We report on fast electro-optic switching (response time 0.1 ms) of a blue-phase-polymer templated nematic with a broad-temperature range of thermodynamic stability and hysteresis-free performance. The nematic fills a polymer template that imposes a periodic structure with cubic symmetry and submicron period. In the field-free state, the nematic in polymer template is optically isotropic. An applied electric field causes non-zero optical retardance. The approach thus combines beneficial structural and optical features of the blue phase (cubic structure with submicron periodicity) and superior thermodynamic stability and electro-optic switching ability of the nematic filler.

  17. Temperature-driven band inversion in Pb?.??Sn?.??Se: Optical and Hall-effect studies

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Anand, Naween; Gu, Genda; Buvaev, Sanal; Hebard, A. F.; Tanner, D. B.; Chen, Zhiguo; Li, Zhiqiang; Choudhary, Kamal; Sinnott, S. B.; Martin, C.

    2014-12-01T23:59:59.000Z

    Optical and Hall-effect measurements have been performed on single crystals of Pb?.??Sn?.??Se, a IV-VI mixed chalcogenide. The temperature dependent (10–300 K) reflectance was measured over 40–7000 cm?¹ (5–870 meV) with an extension to 15,500 cm?¹ (1.92 eV) at room temperature. The reflectance was fit to the Drude-Lorentz model using a single Drude component and several Lorentz oscillators. The optical properties at the measured temperatures were estimated via Kramers-Kronig analysis as well as by the Drude-Lorentz fit. The carriers were p-type with the carrier density determined by Hall measurements. A signature of valence intraband transition is found in the low-energy opticalmore »spectra. It is found that the valence-conduction band transition energy as well as the free carrier effective mass reach minimum values at 100 K, suggesting temperature-driven band inversion in the material. Density function theory calculation for the electronic band structure also make similar predictions.« less

  18. Fiber optic spectroscopic digital imaging sensor and method for flame properties monitoring

    DOE Patents [OSTI]

    Zelepouga, Serguei A. (Hoffman Estates, IL); Rue, David M. (Chicago, IL); Saveliev, Alexei V. (Chicago, IL)

    2011-03-15T23:59:59.000Z

    A system for real-time monitoring of flame properties in combustors and gasifiers which includes an imaging fiber optic bundle having a light receiving end and a light output end and a spectroscopic imaging system operably connected with the light output end of the imaging fiber optic bundle. Focusing of the light received by the light receiving end of the imaging fiber optic bundle by a wall disposed between the light receiving end of the fiber optic bundle and a light source, which wall forms a pinhole opening aligned with the light receiving end.

  19. Fast nondestructive temperature measurement of two-electron atoms in a magneto-optical trap

    SciTech Connect (OSTI)

    Cristiani, Matteo; Valenzuela, Tristan; Gothe, Hannes; Eschner, Juergen [ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, E-08860 Castelldefels (Barcelona) (Spain)

    2010-06-15T23:59:59.000Z

    We extend the technique originally proposed by [Honda et al., Phys. Rev. A 59, R934 (1999)] to measure the temperature of ytterbium and alkaline-earth-metal atoms confined in a magneto-optical trap (MOT). The method is based on the analysis of excitation spectra obtained by probing the {sup 1}S{sub 0}{yields}{sup 3}P{sub 1} intercombination line. Thanks to a careful analysis and modeling of the effects caused by the MOT light on the probe transition we overcome the resolution and precision limits encountered in previous works. Ground-state light shift and Rabi broadening are measured and successfully compared with calculated values. This knowledge allows us to properly extract the Doppler contribution to the linewidth, thus obtaining a reliable measurement of the cloud temperature. We finally show how spectroscopy on free-falling atoms provides an alternative method to determine the sample temperature which resembles the standard time-of-flight technique.

  20. Experimental & Numerical Investigation of Pool Boiling on Engineered Surfaces with Integrated Thin-flim Temperature Sensors 

    E-Print Network [OSTI]

    Sathyamurthi, Vijaykumar

    2011-02-22T23:59:59.000Z

    The objective of this investigation is to measure and analyze surface temperature fluctuations in pool boiling. The surface temperature fluctuations were recorded on silicon surfaces with and without multi-walled carbon nanotubes (MWCNT). Novel Thin...

  1. Dependences of the Al thickness and annealing temperature on the structural, optical and electrical properties in ZnO/Al multilayers

    E-Print Network [OSTI]

    Huang, Jung-Chun

    displays, electrochromic windows, electro-optical devices, gas sensors and solar cells. Nowadays, tin (TCO) films are currently of great commercial and scientific importance for applications in flat panel

  2. HIGH TEMPERATURE IRRADIATION RESISTANT THERMOCOUPLES – A LOW COST SENSOR FOR IN-PILE TESTING AT HIGH TEMPERATURES

    SciTech Connect (OSTI)

    Joy L. Rempe; Darrell L. Knudson; Keith G. Condie; S. Curtis Wilkins; Joshua E. Daw

    2008-06-01T23:59:59.000Z

    Several options have been identified to improve recently-developed Idaho National Laboratory (INL) High Temperature Irradiation Resistant ThermoCouples (HTIR-TCs) for in-pile testing. These options have the potential to reduce fabrication costs and allow HTIR-TC use in higher temperature applications (up to at least 1800 °C). The INL and the University of Idaho (UI) investigated these options with the ultimate objective of providing recommendations for alternate thermocouple designs that are optimized for various applications. This paper summarizes results from these INL/UI investigations. Specifically, results are reported about several options found to enhance HTIR-TC performance, such as improved heat treatments, alternate geometries, alternate fabrication techniques, and the use of copper/nickel alloys as soft extension cable.

  3. The monitoring and multiplexing of fiber optic sensors using chirped laser sources 

    E-Print Network [OSTI]

    Wan, Xiaoke

    2004-09-30T23:59:59.000Z

    . Linearization of the chirp rate has been achieved using feedback from a fiber Fabry-Perot interferometer (FFPI) to adjust the voltage ramp which drives the rotating mirror. In a demonstration of monitoring an array of two fiber Bragg grating (FBG) sensors, a...

  4. Fiber optic temperature sensor using a grating on an angled fiber tip

    E-Print Network [OSTI]

    Varadarajan, Harini

    2000-01-01T23:59:59.000Z

    CHAPTER Page 2. Spinning the Photo Resist. 20 3. Laser Exposure 21 4. Photo Resist Developing. . . . 25 5. Etching the Fiber. 26 B. Testing 29 1. Test Setup. 2. Test Results 29 30 V CONCLUSIONS. . 40 VI RECOMMENDED FUTURE RESEARCH . . 41.... Reusable Polishing Puck. . 14 . 17 11. Fibers in the Polishing Puck. 12. Polish Pad Surfaces. 13. Profile of Polished Fibers. 14. Photograph of Polished Fibers on Metal Puck 18 19 . 19 . 20 15. Argon Laser Setup. 22 16. Laser Setup Details. 23...

  5. A synergetic use of satellite imagery from SAR and optical sensors to improve coastal flood mapping in the Gulf of Mexico

    E-Print Network [OSTI]

    Central Florida, University of

    A synergetic use of satellite imagery from SAR and optical sensors to improve coastal flood mapping for inundation mapping and have a great potential for evaluating wetting/drying algorithms of inland and coastal and near infrared domains. Images acquired in these wavelengths (i.e. visible and near infrared

  6. Thermal history sensors for non-destructive temperature measurements in harsh environments

    SciTech Connect (OSTI)

    Pilgrim, C. C. [Mechanical Engineering, Imperial College London, London, SW7 2AZ, UK and Sensor Coating Systems, Imperial Incubator, Bessemer Building, Level 1 and 2, Imperial College London, London SW7 2AZ (United Kingdom); Heyes, A. L. [Energy Technology and Innovation Initiative, University of Leeds, Leeds, LS2 9JT (United Kingdom); Feist, J. P. [Sensor Coating Systems, Imperial Incubator, Bessemer Building, Level 1 and 2, Imperial College London, London SW7 2AZ (United Kingdom)

    2014-02-18T23:59:59.000Z

    The operating temperature is a critical physical parameter in many engineering applications, however, can be very challenging to measure in certain environments, particularly when access is limited or on rotating components. A new quantitative non-destructive temperature measurement technique has been proposed which relies on thermally induced permanent changes in ceramic phosphors. This technique has several distinct advantages over current methods for many different applications. The robust ceramic material stores the temperature information allowing long term thermal exposures in harsh environment to be measured at a convenient time. Additionally, rare earth dopants make the ceramic phosphorescent so that the temperature information can be interpreted by automated interrogation of the phosphorescent light. This technique has been demonstrated by application of YAG doped with dysprosium and europium as coatings through the air-plasma spray process. Either material can be used to measure temperature over a wide range, namely between 300°C and 900°C. Furthermore, results show that the material records the peak exposure temperature and prolonged exposure at lower temperatures would have no effect on the temperature measurement. This indicates that these materials could be used to measure peak operating temperatures in long-term testing.

  7. Optical fiber sensor technique for strain measurement during materials deposition, chemical reaction, and relaxation

    DOE Patents [OSTI]

    Butler, M.A.; Ginley, D.S.

    1988-01-21T23:59:59.000Z

    Laser light from a common source is split and conveyed through two similar optical fibers and emitted at their respective ends to form an interference pattern, one of the optical fibers having a portion thereof subjected to a strain. Changes in the strain cause changes in the optical path length of the strain fiber, and generate corresponding changes in the interference pattern. The interference pattern is received and transduced into signals representative of fringe shifts corresponding to changes in the strain experienced by the strained one of the optical fibers. These signals are then processed to evaluate strain as a function of time, typical examples of the application of the apparatus including electrodeposition of a metallic film on a conductive surface provided on the outside of the optical fiber being strained, so that strains generated in the optical fiber during the course of the electrodeposition are measurable as a function of time. In one aspect of the invention, signals relating to the fringe shift are stored for subsequent processing and analysis, whereas in another aspect of the invention the signals are processed for real-time display of the strain changes under study. 9 figs.

  8. Matchstick: A Room-to-Room Thermal Model for Predicting Indoor Temperature from Wireless Sensor Data

    E-Print Network [OSTI]

    Hazas, Mike

    that our model can predict future indoor temperature trends with a 90th percentile aggregate error between thermo- stat actuates the heating, ventilation, and air condition- ing (HVAC) infrastructure to bring and these energy approaches, a heating model could allow future temperature trends to be predicted using

  9. Power inverter with optical isolation

    DOE Patents [OSTI]

    Duncan, Paul G.; Schroeder, John Alan

    2005-12-06T23:59:59.000Z

    An optically isolated power electronic power conversion circuit that includes an input electrical power source, a heat pipe, a power electronic switch or plurality of interconnected power electronic switches, a mechanism for connecting the switch to the input power source, a mechanism for connecting comprising an interconnecting cable and/or bus bar or plurality of interconnecting cables and/or input bus bars, an optically isolated drive circuit connected to the switch, a heat sink assembly upon which the power electronic switch or switches is mounted, an output load, a mechanism for connecting the switch to the output load, the mechanism for connecting including an interconnecting cable and/or bus bar or plurality of interconnecting cables and/or output bus bars, at least one a fiber optic temperature sensor mounted on the heat sink assembly, at least one fiber optic current sensor mounted on the load interconnection cable and/or output bus bar, at least one fiber optic voltage sensor mounted on the load interconnection cable and/or output bus bar, at least one fiber optic current sensor mounted on the input power interconnection cable and/or input bus bar, and at least one fiber optic voltage sensor mounted on the input power interconnection cable and/or input bus bar.

  10. Real time perfusion and oxygenation monitoring in an implantable optical sensor

    E-Print Network [OSTI]

    Subramanian, Hariharan

    2006-04-12T23:59:59.000Z

    in operating rooms. In the late 1970s Scott Wilbur of the Biox corporation designed an ear sensor that used light emitting diode and solid state photodetectors to develop a clinically accepted pulse oximeter. The fiberoptic cables of previous ear oximeters.... Traditional oximeters use two light emitting diodes that emit light at 660nm (red) and 940nm (infrared) wavelengths. At these wavelengths both oxyhemoglobin and reduced hemoglobin have different absorption spectra (Fig. 1). The ratio of absorbances...

  11. Real time perfusion and oxygenation monitoring in an implantable optical sensor 

    E-Print Network [OSTI]

    Subramanian, Hariharan

    2006-04-12T23:59:59.000Z

    in operating rooms. In the late 1970s Scott Wilbur of the Biox corporation designed an ear sensor that used light emitting diode and solid state photodetectors to develop a clinically accepted pulse oximeter. The fiberoptic cables of previous ear oximeters.... Traditional oximeters use two light emitting diodes that emit light at 660nm (red) and 940nm (infrared) wavelengths. At these wavelengths both oxyhemoglobin and reduced hemoglobin have different absorption spectra (Fig. 1). The ratio of absorbances...

  12. Observation of optical spin injection into Ge-based structures at room temperature

    SciTech Connect (OSTI)

    Yasutake, Yuhsuke; Hayashi, Shuhei; Fukatsu, Susumu [Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902 (Japan)] [Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902 (Japan); Yaguchi, Hiroyuki [Graduate School of Science and Engineering, Saitama University, Shimo-Okubo 255, Sakura, Saitama 338-8570 (Japan)] [Graduate School of Science and Engineering, Saitama University, Shimo-Okubo 255, Sakura, Saitama 338-8570 (Japan)

    2013-06-17T23:59:59.000Z

    Non-zero spin polarization induced by optical orientation was clearly observed at room temperature in a Ge/Ge{sub 0.8}Si{sub 0.2} quantum well grown on Ge and a Ge layer grown on Si by molecular beam epitaxy, whereas it was absent in bulk Ge. This occurred because indirect-gap photoluminescence (PL), which can obscure the spin-polarization information carried by the direct-gap PL, was quenched by unintentional growth-related defects in the epitaxial layers. Such interpretation was confirmed by applying time gating that effectively removed the indirect-gap PL characterized by a slower rise time, which allowed us to demonstrate the existence of room-temperature spin polarization in bulk Ge.

  13. Method for measuring surface temperature

    DOE Patents [OSTI]

    Baker, Gary A. (Los Alamos, NM); Baker, Sheila N. (Los Alamos, NM); McCleskey, T. Mark (Los Alamos, NM)

    2009-07-28T23:59:59.000Z

    The present invention relates to a method for measuring a surface temperature using is a fluorescent temperature sensor or optical thermometer. The sensor includes a solution of 1,3-bis(1-pyrenyl)propane within a 1-butyl-1-1-methyl pyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid solvent. The 1,3-bis(1-pyrenyl)propane remains unassociated when in the ground state while in solution. When subjected to UV light, an excited state is produced that exists in equilibrium with an excimer. The position of the equilibrium between the two excited states is temperature dependent.

  14. A low temperature nonlinear optical rotational anisotropy spectrometer for the determination of crystallographic and electronic symmetries

    SciTech Connect (OSTI)

    Torchinsky, Darius H.; Hsieh, David [Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Department of Physics, California Institute of Technology, Pasadena, California 91125 (United States); Chu, Hao [Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Department of Applied Physics, California Institute of Technology, Pasadena, California 91125 (United States); Qi, Tongfei; Cao, Gang [Center for Advanced Materials, Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506 (United States)

    2014-08-15T23:59:59.000Z

    Nonlinear optical generation from a crystalline material can reveal the symmetries of both its lattice structure and underlying ordered electronic phases and can therefore be exploited as a complementary technique to diffraction based scattering probes. Although this technique has been successfully used to study the lattice and magnetic structures of systems such as semiconductor surfaces, multiferroic crystals, magnetic thin films, and multilayers, challenging technical requirements have prevented its application to the plethora of complex electronic phases found in strongly correlated electron systems. These requirements include an ability to probe small bulk single crystals at the ?m length scale, a need for sensitivity to the entire nonlinear optical susceptibility tensor, oblique light incidence reflection geometry, and incident light frequency tunability among others. These measurements are further complicated by the need for extreme sample environments such as ultra low temperatures, high magnetic fields, or high pressures. In this review we present a novel experimental construction using a rotating light scattering plane that meets all the aforementioned requirements. We demonstrate the efficacy of our scheme by making symmetry measurements on a ?m scale facet of a small bulk single crystal of Sr{sub 2}IrO{sub 4} using optical second and third harmonic generation.

  15. A Wireless Passive RCS-based Temperature Sensor using Liquid Metal and Microfluidics Technologies

    E-Print Network [OSTI]

    Tentzeris, Manos

    problem in electronic device maintenance, refrigerated food transport, agriculture and nuclear waste allow for the power/cost-efficient real-time temperature monitoring in agriculture and other mass

  16. Utilizing Distributed Temperature Sensors in Predicting Flow Rates in Multilateral Wells

    E-Print Network [OSTI]

    Al Mulla, Jassim Mohammed A.

    2012-07-16T23:59:59.000Z

    The new advancement in well monitoring tools have increased the amount of data that could be retrieved with great accuracy. Downhole pressure and temperature could be precisely determined now by using modern instruments. The new challenge that we...

  17. February 8, 2010 2.7V, SOT-23 or TO-92 Temperature Sensor

    E-Print Network [OSTI]

    Bezrukov, Sergei

    than 110 A, self-heating is limited to a very low 0.1°C in still air in the SOT-23 package. Shutdown Temperature Profile specifications. Refer to www.national.com/packaging. (Note 4) Electrical Characteristics

  18. Performance optimization of apodized FBG-based temperature sensors in single and quasi-distributed DWDM systems with new and different apodization profiles

    SciTech Connect (OSTI)

    Mohammed, Nazmi A. [Research Center, Smart Village, College of Engineering, Arab Academy for Science, Technology, and Maritime Transport, Cairo (Egypt)] [Research Center, Smart Village, College of Engineering, Arab Academy for Science, Technology, and Maritime Transport, Cairo (Egypt); Ali, Taha A., E-mail: Taha25@gmail.com; Aly, Moustafa H. [Department of Electronics and Communications Engineering, College of Engineering, Arab Academy for Science, Technology, and Maritime Transport, Cairo (Egypt)] [Department of Electronics and Communications Engineering, College of Engineering, Arab Academy for Science, Technology, and Maritime Transport, Cairo (Egypt)

    2013-12-15T23:59:59.000Z

    In this work, different FBG temperature sensors are designed and evaluated with various apodization profiles. Evaluation is done under a wide range of controlling design parameters like sensor length and refractive index modulation amplitude, targeting a remarkable temperature sensing performance. New judgment techniques are introduced such as apodization window roll-off rate, asymptotic sidelobe (SL) decay level, number of SLs, and average SL level (SLav). Evaluation techniques like reflectivity, Full width at Half Maximum (FWHM), and Sidelobe Suppression Ratio (SLSR) are also used. A “New” apodization function is proposed, which achieves better performance like asymptotic decay of 18.4 dB/nm, high SLSR of 60 dB, high channel isolation of 57.9 dB, and narrow FWHM less than 0.15 nm. For a single accurate temperature sensor measurement in extensive noisy environment, optimum results are obtained by the Nuttall apodization profile and the new apodization function, which have remarkable SLSR. For a quasi-distributed FBG temperature sensor the Barthann and the new apodization profiles obtain optimum results. Barthann achieves a high asymptotic decay of 40 dB/nm, a narrow FWHM (less than 25 GHZ), a very low SLav of ?45.3 dB, high isolation of 44.6 dB, and a high SLSR of 35 dB. The new apodization function achieves narrow FWHM of 0.177 nm, very low SL of ?60.1, very low SLav of ?63.6 dB, and very high SLSR of ?57.7 dB. A study is performed on including an unapodized sensor among apodized sensors in a quasi-distributed sensing system. Finally, an isolation examination is performed on all the discussed apodizations and a linear relation between temperature and the Bragg wavelength shift is observed experimentally and matched with the simulated results.

  19. An Optical Offgas Sensor Network Incorporating a HG Cavity Ringdown Spectrometer and IR Diode Lasers

    SciTech Connect (OSTI)

    George P. Miller

    2007-12-30T23:59:59.000Z

    A multi-element cavity ringdown system was evaluated with the objective of developing an intelligent sensor network to be incorporated into the control systems for advanced coal combustion facilities. Using a combination of a YAG-pumped dye laser and a tunable NIR/IR laser a dual cavity was constructed and a labview program was developed to provide multi-channel, real-time data to permit the real-time monitoring of typical exhaust emission gases, (for example: CO{sub 2}, SO{sub 2}, and mercury) of concern to the next generation of coal-powered facilities.

  20. Fiberoptic Fabry-Perot engine pressure sensor system using a continuous wave laser source 

    E-Print Network [OSTI]

    Choi, Han-Sun

    1994-01-01T23:59:59.000Z

    A fiber optic Fabry-Perot engine pressure sensor using a continuous wave laser source is implemented and tested. The operating point of the Fabrv-Perot sensor is locked to the quadrature point by electronic feedback control of laser temperature...

  1. Nanocomposite thin films for high temperature optical gas sensing of hydrogen

    DOE Patents [OSTI]

    Ohodnicki, Jr., Paul R.; Brown, Thomas D.

    2013-04-02T23:59:59.000Z

    The disclosure relates to a plasmon resonance-based method for H.sub.2 sensing in a gas stream at temperatures greater than about 500.degree. C. utilizing a hydrogen sensing material. The hydrogen sensing material is comprised of gold nanoparticles having an average nanoparticle diameter of less than about 100 nanometers dispersed in an inert matrix having a bandgap greater than or equal to 5 eV, and an oxygen ion conductivity less than approximately 10.sup.-7 S/cm at a temperature of 700.degree. C. Exemplary inert matrix materials include SiO.sub.2, Al.sub.2O.sub.3, and Si.sub.3N.sub.4 as well as modifications to modify the effective refractive indices through combinations and/or doping of such materials. At high temperatures, blue shift of the plasmon resonance optical absorption peak indicates the presence of H.sub.2. The method disclosed offers significant advantage over active and reducible matrix materials typically utilized, such as yttria-stabilized zirconia (YSZ) or TiO.sub.2.

  2. In Vitro and In Vivo Comparison of Optics and Performance of a Distal Sensor Ureteroscope Versus a Standard Fiberoptic Ureteroscope

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    characteristics and optics of the X C with a stan- dardand In Vivo Comparison of Optics and Performance of a Distalperformance characteristics and optics of a new generation

  3. Abstract An application of gas sensors for rapid bio-analysis is presented. An array of temperature-modulated

    E-Print Network [OSTI]

    Gutierrez-Osuna, Ricardo

    Abstract An application of gas sensors for rapid bio- analysis is presented. An array by a chemical compound. This finding suggests the possibility of using cross-selective gas-sensor arrays conditions of the cells. Electronic nose systems, which rely on a combination of cross-selective gas sensors

  4. FIBER OPTICAL MICRO-DETECTORS FOR OXYGEN SENSING IN POWER PLANTS

    SciTech Connect (OSTI)

    Gregory L. Baker; Ruby N. Ghosh; D.J. Osborn III

    2004-10-01T23:59:59.000Z

    A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. High temperature measurements of the emission of clusters in sol gel films show that the luminescence intensity from the films follow a 1/T relationship from room temperature to 150 C, and then declines at a slower rate at higher temperatures. The large number of photons available at 230 C is consistent with simple low cost optics for fiber optic probes based on the emission from clusters in sol gel films.

  5. An optical fiber Faraday effect current sensor for power system applications

    E-Print Network [OSTI]

    Short, Shayne Xavier

    1995-01-01T23:59:59.000Z

    sensing applications, the magnetic field that is employed is that which is induced by a current passing through a conductor. The Faraday efi'ect has been under continual study for over thirty years for mag- netic field sensing, with emphasis in recent... the conductor. For these applications, the Verdet constant is commonly given in terms of the current passing through the conductor. The most common Verdet constant value used for single-mode optical fiber is shown below. This is the value used...

  6. SU-E-T-111: Development of Proton Dosimetry System Using Fiber-Optic Cerenkov Radiation Sensor Array

    SciTech Connect (OSTI)

    Son, J [National Cancer Center, Ilsan, Gyeonggi-do, Korea University, Seoul (Korea, Republic of); Kim, M; Shin, D; Lim, Y; Lee, S; Kim, J; Kim, J [National Cancer Center, Goyangsi, Gyeonggi-do (Korea, Republic of); Hwang, U [National Medical Center in Korea, Seoul, Seoul (Korea, Republic of); Yoon, M [Korea University, Seoul (Korea, Republic of)

    2014-06-01T23:59:59.000Z

    Purpose: We had developed and evaluated a new dosimetric system for proton therapy using array of fiber-optic Cerenkov radiation sensor (FOCRS) which can measure a percent depth dose (PDD) instantly. In this study, the Bragg peaks and spread out Bragg peak (SOBP) of the proton beams measured by FOCRS array were compared with those measured by an ion chamber. Methods and Method: We fabricated an optical fiber array of FOCRS in a handmade phantom which is composed of poly-methyl methacrylate (PMMA). There are 75 holes of 1mm diameter inside the phantom which is designed to be exposed in direction of beam when it is emerged in water phantom. The proton beam irradiation was carried out using IBA cyclotron PROTEUS 235 at national cancer center in Korea and a commercial data acquisition system was used to digitize the analog signal. Results: The measured Bragg peak and SOBP for the proton ranges of 7? 20 cm were well matched with the result from ion chamber. The comparison results show that the depth of proton beam ranges and the width of SOBP measured by array of FOCRS are comparable with the measurement from multi-layer ion chamber (MLIC) although there are some uncertainty in the measurement of FOCRS array for some specific beam ranges. Conclusion: The newly developed FOCRS array based dosimetric system for proton therapy can efficiently reduce the time and effort needed for proton beam range measurement compared to the conventional method and has the potential to be used for the proton pencil beam application.

  7. Effect of ultraviolet radiation exposure on room-temperature hydrogen sensitivity of nanocrystalline doped tin oxide sensor incorporated into microelectromechanical systems device

    SciTech Connect (OSTI)

    Shukla, Satyajit; Agrawal, Rajnikant; Cho, Hyoung J.; Seal, Sudipta; Ludwig, Lawrence; Parish, Clyde [Advanced Materials Processing and Analysis Center (AMPAC) and Mechanical Materials Aerospace Engineering (MMAE) Department, Engineering 381, University of Central Florida, 4000 Central Florida Boulevard, Orlando, Florida 32816 (United States); National Aeronautics and Space Administration (NASA), John F. Kennedy Space Center, Kennedy Space Center (KSC), Florida 32899 (United States)

    2005-03-01T23:59:59.000Z

    The effect of ultraviolet (UV) radiation exposure on the room-temperature hydrogen (H{sub 2}) sensitivity of nanocrystalline indium oxide (In{sub 2}O{sub 3})-doped tin oxide (SnO{sub 2}) thin-film gas sensor is investigated in this article. The present sensor is incorporated into microelectromechanical systems device using sol-gel dip-coating technique. The present sensor exhibits a very high sensitivity, as high as 65 000-110 000, at room temperature, for 900 ppm of H{sub 2} under the dynamic test condition without UV exposure. The H{sub 2} sensitivity is, however, observed to reduce to 200 under UV radiation, which is contrary to the literature data, where an enhanced room-temperature gas sensitivity has been reported under UV radiation. The observed phenomenon is attributed to the reduced surface coverage by the chemisorbed oxygen ions under UV radiation, which is in consonance with the prediction of the constitutive equation, proposed recently by the authors, for the gas sensitivity of nanocrystalline semiconductor oxide thin-film sensors.

  8. Morphology and Optical Properties of Mg Doped GaNNanowires in Dependence of Growth Temperature

    SciTech Connect (OSTI)

    Sutter, E.

    2010-06-17T23:59:59.000Z

    The influence of the substrate temperature and Mg doping on the morphological and optical properties of catalyst-free GaN nanowires grown by plasma-assisted molecular beam epitaxy on Si(111) has been investigated in a large temperaturerange between 665 °C and 785 °C. The density and wire sizes in Mg-doped nanowires are found to change with substrate temperature in a similar way as undoped nanowires. Between 725 °C and 785 °C a trimodal size distribution and an increase of the wire density from 5.0x109 cm-2 to 9.5x109 cm-2 were observed. Transmission electron microscopy indicates that the upper parts of the nanowires are free of structural defects. Raman spectroscopy measurements confirm a high crystalline quality of doped wires, with a line width of the E2 H of 3.3 cm-1 for samples grown at Ts=785 °C. Photoluminescence measurements show a strong influence of Mg on the emission properties, namely the increase of thedonor-acceptor pair emission and its phonon replicas.

  9. How do A-train Sensors Intercompare in the Retrieval of Above-Cloud Aerosol Optical Depth? A Case Study-based Assessment

    SciTech Connect (OSTI)

    Jethva, H. T.; Torres, O.; Waquet, F.; Chand, Duli; Hu, Yong X.

    2014-01-16T23:59:59.000Z

    We inter-compare the above-cloud aerosol optical depth (ACAOD) of biomass burning plumes retrieved from different A-train sensors, i.e., MODIS, CALIOP, POLDER, and OMI. These sensors have shown independent capabilities to detect and retrieve aerosol loading above marine boundary layer clouds--a kind of situation often found over the Southeast Atlantic Ocean during dry burning season. A systematic one-to-one comparison reveals that, in general, all passive sensors and CALIOP-based research methods derive comparable ACAOD with differences mostly within 0.2 over homogeneous cloud fields. The 532-nm ACAOD retrieved by CALIOP operational algorithm is largely underestimated; however, it’s 1064-nm AOD when converted to 500 nm shows closer agreement to the passive sensors. Given the different types of sensor measurements processed with different algorithms, the close agreement between them is encouraging. Due to lack of adequate direct measurements above cloud, the validation of satellite-based ACAOD retrievals remains an open challenge. The inter-satellite comparison, however, can be useful for the relative evaluation and consistency check.

  10. Shape memory alloy thaw sensors

    SciTech Connect (OSTI)

    Shahinpoor, Mohsen (Albuquerque, NM); Martinez, David R. (Albuquerque, NM)

    1998-01-01T23:59:59.000Z

    A sensor permanently indicates that it has been exposed to temperatures exceeding a critical temperature for a predetermined time period. An element of the sensor made from shape memory alloy changes shape when exposed, even temporarily, to temperatures above the Austenitic temperature of the shape memory alloy. The shape change of the SMA element causes the sensor to change between two readily distinguishable states.

  11. Use of sensors in monitoring civil structures

    E-Print Network [OSTI]

    Daher, Bassam William, 1979-

    2004-01-01T23:59:59.000Z

    This thesis surveys the use of sensors and sensor networks in monitoring civil structures, with particular emphasis on the monitoring of bridges and highways using fiber optic sensors. Following a brief review of the most ...

  12. The influence of substrate temperature on the structural and optical properties of ZnS thin films

    SciTech Connect (OSTI)

    Ashraf, M.; Akhtar, S. M. J.; Ali, Z. [Optics Laboratories (Pakistan); Qayyum, A., E-mail: qayyum@pinstech.org.pk [Pakistan Institute of Nuclear Science and Technology, P.O. Nilore, Physics Division (Pakistan)

    2011-05-15T23:59:59.000Z

    Thin films of ZnS were deposited on soda lime glass substrates by a modified close-space sublimation technique. The change in optical and structural properties of the films deposited at various substrate temperatures (150-450 Degree-Sign C) was investigated. X-ray diffraction spectra showed that films were polycrystalline in nature having cubic structure oriented only along (111) plan. The crystallinity of films increased with the substrate temperature up to 250 Degree-Sign C. However, crystallinity decreased with further increase of substrate temperature and films became amorphous at 450 Degree-Sign C. The atomic force microscopy data revealed that the films become more uniform and dense with the increase of substrate temperature. Optical properties of the films were determined from the transmittance data using Swanepoel model. It was observed that the energy band gap is increased from 3.52 to 3.65 eV and refractive index of the films are decreased with the increase of substrate temperature. Moreover, considerable improvement in blue response of the films was noticed with increasing substrate temperature.

  13. Planar optical waveguide based sandwich assay sensors and processes for the detection of biological targets including protein markers, pathogens and cellular debris

    DOE Patents [OSTI]

    Martinez, Jennifer S. (Santa Fe, NM); Swanson, Basil I. (Los Alamos, NM); Grace, Karen M. (Los Alamos, NM); Grace, Wynne K. (Los Alamos, NM); Shreve, Andrew P. (Santa Fe, NM)

    2009-06-02T23:59:59.000Z

    An assay element is described including recognition ligands bound to a film on a single mode planar optical waveguide, the film from the group of a membrane, a polymerized bilayer membrane, and a self-assembled monolayer containing polyethylene glycol or polypropylene glycol groups therein and an assay process for detecting the presence of a biological target is described including injecting a biological target-containing sample into a sensor cell including the assay element, with the recognition ligands adapted for binding to selected biological targets, maintaining the sample within the sensor cell for time sufficient for binding to occur between selected biological targets within the sample and the recognition ligands, injecting a solution including a reporter ligand into the sensor cell; and, interrogating the sample within the sensor cell with excitation light from the waveguide, the excitation light provided by an evanescent field of the single mode penetrating into the biological target-containing sample to a distance of less than about 200 nanometers from the waveguide thereby exciting the fluorescent-label in any bound reporter ligand within a distance of less than about 200 nanometers from the waveguide and resulting in a detectable signal.

  14. A Comparative Study of Optical and Ultraviolet Effective Temperatures for DA White Dwarfs from the IUE Archive

    E-Print Network [OSTI]

    C. -P. Lajoie; P. Bergeron

    2007-06-20T23:59:59.000Z

    We present a comparative study of effective temperatures determined from the hydrogen Balmer lines and from the UV energy distribution for 140 DA white dwarfs drawn from the IUE archive. Our results indicate that the optical and UV temperatures of the majority of stars below T~40,000 K and within ~75 pc are in fairly good agreement given the uncertainties. At higher temperatures and/or larger distances, however, significant discrepancies are observed. Several mechanisms are investigated to account for these discrepancies including the effect of interstellar reddening, the presence of metals in the photosphere, and the existence of unresolved binary white dwarfs. The results of our analysis reveal that wavelength-dependent extinction is the most natural explanation for the observed temperature differences. We also attempt to predict the differences in optical and UV temperatures expected from unresolved degenerate binaries by performing an exhaustive simulation of composite model spectra. In light of these simulations, we then discuss some known double degenerates and identify new binary candidates by restricting our analysis to stars located within 75 pc where the effect of interstellar reddening is significantly reduced.

  15. Moisture sensor based on evanescent wave light scattering by porous sol-gel silica coating

    DOE Patents [OSTI]

    Tao, Shiquan; Singh, Jagdish P.; Winstead, Christopher B.

    2006-05-02T23:59:59.000Z

    An optical fiber moisture sensor that can be used to sense moisture present in gas phase in a wide range of concentrations is provided, as well techniques for making the same. The present invention includes a method that utilizes the light scattering phenomenon which occurs in a porous sol-gel silica by coating an optical fiber core with such silica. Thus, a porous sol-gel silica polymer coated on an optical fiber core forms the transducer of an optical fiber moisture sensor according to an embodiment. The resulting optical fiber sensor of the present invention can be used in various applications, including to sense moisture content in indoor/outdoor air, soil, concrete, and low/high temperature gas streams.

  16. Fiber Optical Micro-detectors for Oxygen Sensing in Power Plants

    SciTech Connect (OSTI)

    Gregory L. Baker; Ruby N. Ghosh; D. J. Osborn; Po Zhang

    2006-09-30T23:59:59.000Z

    A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. Our approach towards immobilizing the potassium salt of the molybdenum cluster, K{sub 2}Mo{sub 6}Cl{sub 14}, at the far end of an optical fiber is to embed the cluster in a thermally cured sol-gel matrix particle. Due to the improved mechanical properties of this approach high temperature sensor measurements were performed up to 100 C. These are promising results for a high temperature fiber optical oxygen sensor based on molybdenum chloride clusters.

  17. Buried fiber optic sensor

    E-Print Network [OSTI]

    Park, Jaehee

    1992-01-01T23:59:59.000Z

    , and TMom modes. Otherwise vm gives the HEv hm and EHv-hm modest20] 18 Table I. Parameters of the laser source and the fused silica fiber which are used in this experiment. n=n1=1. 4527 n2= 1. 4483 D (core diameter )= 8 um Cladding Diameter = 125 um... Interferometer . B. Frequency Chirping of Laser Diode C. Pressure Sensitivity to Uniform Pressure . . . . . . . . . . D. Pressure Sensitivity to Transverse Pressure . . . . E. Pressure Sensitivity to Longitudinal Pressure . . . . . . . . . . I 3 . . . . 20...

  18. Comparison of junction temperature evaluations in a power IGBT module using an IR camera and three thermo-sensitive electrical parameters

    E-Print Network [OSTI]

    and electrical methods. The main optical methods are local infrared sensors [3,4], optical fibers [5], infraredComparison of junction temperature evaluations in a power IGBT module using an IR camera and three information of the actual chip temperature distribution. In this paper, we propose to use infrared (IR

  19. An evaluation of an optically-based, cylinder pressure sensor in a single-cylinder, research, diesel engine 

    E-Print Network [OSTI]

    Turner, Timothy Troy

    1994-01-01T23:59:59.000Z

    in head bolts were tested under a variety of operating conditions on a single cylinder, research, diesel engine. The sensors' pressure vs. crank angle output was compared with the output of a piezoelectric pressure transducer mounted, in the engine head...

  20. Fiber Optic Hydrogen Sensor Development: Cooperative Research and Development Final Report, CRADA number CRD-05-00158

    SciTech Connect (OSTI)

    Ringer, M.

    2010-07-01T23:59:59.000Z

    NREL and Nuclear Filter Technology collaborated to develop a prototype product for a hydrogen threshold sensor that was used to monitor hydrogen production in the transport of nuclear waste transport containers.

  1. Correlation of optical properties and temperature-induced irreversible phase transitions in europium-doped yttrium carbonate nanoparticles

    SciTech Connect (OSTI)

    Gunawidjaja, Ray; Myint, Thandar [Applied Sciences Laboratory, Institute for Shock Physics, Washington State University, Spokane, WA 99210-1495 (United States); Eilers, Hergen, E-mail: eilers@wsu.edu [Applied Sciences Laboratory, Institute for Shock Physics, Washington State University, Spokane, WA 99210-1495 (United States)

    2011-12-15T23:59:59.000Z

    Nanophase europium-doped yttrium carbonate precursors are subjected to heat treatments, ranging from 300 Degree-Sign C to 1100 Degree-Sign C for dwell times of 5 min, 30 min, and 180 min. XRD, TEM, FT-IR, fluorescence, fluorescence excitation, and fluorescence lifetime measurements are used to characterize the materials. Upon heating, the material transitions through several amorphous stages until it reaches the crystalline cubic Y{sub 2}O{sub 3} phase. DSC measurements show an exothermic transition at 665.7 Degree-Sign C, indicating the formation of crystalline Y{sub 2}O{sub 3}. The grain size development is fitted by the relaxation equation and yields an activation energy of 50.3 kJ/mol. The amorphous phases are characterized by inhomogenously broadened optical spectra. Heating up to 700 Degree-Sign C leads to an increased fluorescence lifetime (from about 1 ms to 2.4 ms). As the material is heated to higher temperatures and completes the formation of the crystalline cubic Y{sub 2}O{sub 3} phase, the optical spectra become narrower and the fluorescence lifetime decreases to about 1.2 ms. - Graphical abstract: Fluorescence lifetimes of Eu-doped Y{sub 2}O{sub 3} precursors heated for 5, 30, and 180 min to various temperatures. Highlights: Black-Right-Pointing-Pointer Irreversible phase transitions in nanoparticles are of interest for thermometry. Black-Right-Pointing-Pointer Eu-doped nanophase yttrium carbonate precursors were heat-treated. Black-Right-Pointing-Pointer The material undergoes decomposition and crystallization. Black-Right-Pointing-Pointer Morphological and optical properties are measured. Black-Right-Pointing-Pointer Optical properties can be used to deduce the temperature.

  2. Complete Fiber/Copper Cable Solution for Long-Term Temperature and Pressure Measurement in Supercritical Reservoirs and EGS Wells

    Broader source: Energy.gov [DOE]

    Project objectives: 1. Optical fibers that resist hydrogen darkening? for several months instead of hours and days at 300 deg. C and higher. 2. Tube encapsulated cable (TEC) construction that functions as a distributed temperature sensor (DTS) and a power source for a downhole pressure sensor.

  3. Sensor assembly

    DOE Patents [OSTI]

    Bennett, Thomas E.; Nelson, Drew V.

    2004-04-13T23:59:59.000Z

    A ribbon-like sensor assembly is described wherein a length of an optical fiber embedded within a similar lengths of a prepreg tow. The fiber is ""sandwiched"" by two layers of the prepreg tow which are merged to form a single consolidated ribbon. The consolidated ribbon achieving a generally uniform distribution of composite filaments near the embedded fiber such that excess resin does not ""pool"" around the periphery of the embedded fiber.

  4. Geographically distributed environmental sensor system

    DOE Patents [OSTI]

    French, Patrick; Veatch, Brad; O'Connor, Mike

    2006-10-03T23:59:59.000Z

    The present invention is directed to a sensor network that includes a number of sensor units and a base unit. The base station operates in a network discovery mode (in which network topology information is collected) in a data polling mode (in which sensed information is collected from selected sensory units). Each of the sensor units can include a number of features, including an anemometer, a rain gauge, a compass, a GPS receiver, a barometric pressure sensor, an air temperature sensor, a humidity sensor, a level, and a radiant temperature sensor.

  5. Final Technical Report - 300���°C Capable Electronics Platform and Temperature Sensor System For Enhanced Geothermal Systems

    SciTech Connect (OSTI)

    Cheng-Po Chen; David Shaddock; Peter Sandvik; Rich Saia; Amita Patil, Alexey Vert; Tan Zhang

    2012-11-30T23:59:59.000Z

    A silicon carbide (SiC) based electronic temperature sensor prototype has been demonstrated to operate at 300���°C. We showed continuous operation of 1,000 hours with SiC operational amplifier and surface mounted discreet resistors and capacitors on a ceramic circuit board. This feasibility demonstration is a major milestone in the development of high temperature electronics in general and high temperature geothermal exploration and well management tools in particular. SiC technology offers technical advantages that are not found in competing technologies such as silicon-on-insulator (SOI) at high temperatures of 200���°C to 300���°C and beyond. The SiC integrated circuits and packaging methods can be used in new product introduction by GE Oil and Gas for high temperature down-hole tools. The existing SiC fabrication facility at GE is sufficient to support the quantities currently demanded by the marketplace, and there are other entities in the United States and other countries capable of ramping up SiC technology manufacturing. The ceramic circuit boards are different from traditional organic-based electronics circuit boards, but the fabrication process is compatible with existing ceramic substrate manufacturing. This project has brought high temperature electronics forward, and brings us closer to commercializing tools that will enable and reduce the cost of enhanced geothermal technology to benefit the public in terms of providing clean renewable energy at lower costs.

  6. Growth-temperature dependence of optical spin-injection dynamics in self-assembled InGaAs quantum dots

    SciTech Connect (OSTI)

    Yamamura, Takafumi; Kiba, Takayuki; Yang, Xiaojie; Takayama, Junichi; Subagyo, Agus; Sueoka, Kazuhisa; Murayama, Akihiro, E-mail: murayama@ist.hokudai.ac.jp [Graduate School of Information Science and Technology, Hokkaido University, Kita 14, Nishi 9, Kita-ku, Sapporo 060-0814 (Japan)

    2014-09-07T23:59:59.000Z

    The growth-temperature dependence of the optical spin-injection dynamics in self-assembled quantum dots (QDs) of In{sub 0.5}Ga{sub 0.5}As was studied by increasing the sheet density of the dots from 2?×?10{sup 10} to 7?×?10{sup 10}?cm{sup ?2} and reducing their size through a decrease in growth temperature from 500 to 470?°C. The circularly polarized transient photoluminescence (PL) of the resulting QD ensembles was analyzed after optical excitation of spin-polarized carriers in GaAs barriers by using rate equations that take into account spin-injection dynamics such as spin-injection time, spin relaxation during injection, spin-dependent state-filling, and subsequent spin relaxation. The excitation-power dependence of the transient circular polarization of PL in the QDs, which is sensitive to the state-filling effect, was also examined. It was found that a systematic increase occurs in the degree of circular polarization of PL with decreasing growth temperature, which reflects the transient polarization of exciton spin after spin injection. This is attributed to strong suppression of the filling effect for the majority-spin states as the dot-density of the QDs increases.

  7. Accuracy of Distributed Optical Fiber Temperature Sensing for Use in Leak Detection of Subsea Pipelines

    E-Print Network [OSTI]

    Madabhushi, S.; Elshafie, M. Z. E. B.; Haigh, S. K.

    2014-09-25T23:59:59.000Z

    described later. A change of density causes a phonon wave to travel through the medium. Brillouin scattering is the interaction of an electromagnetic wave with this density wave; photon-phonon scattering. The frequency at which the backscattered signal... m to accommodate a 3 m spatial resolution. The applied temperature was modelled as a square pulse of magnitude equal to the applied temperature for the exposed length, and ambient temperature elsewhere. Figure 3 shows the expected output from...

  8. Special Issue "Underwater Sensor Nodes and Underwater Sensor Networks" A special issue of Sensors (ISSN 1424-8220)

    E-Print Network [OSTI]

    Chen, Min

    aquatic environments. Marine surveillance, pollution detection and monitoring, and oceanographic data (salinity, conductivity, turbidity, pH, oxygen, temperature, depth, etc.) - Sediments and pollution sensor nodes - Acoustic sensors - Underwater sensor network architectures - Wired and wireless protocols

  9. Optical keyboard

    DOE Patents [OSTI]

    Veligdan, James T. (Manorville, NY); Feichtner, John D. (Fiddletown, CA); Phillips, Thomas E. (San Diego, CA)

    2001-01-01T23:59:59.000Z

    An optical keyboard includes an optical panel having optical waveguides stacked together. First ends of the waveguides define an inlet face, and opposite ends thereof define a screen. A projector transmits a light beam outbound through the waveguides for display on the screen as a keyboard image. A light sensor is optically aligned with the inlet face for sensing an inbound light beam channeled through the waveguides from the screen upon covering one key of the keyboard image.

  10. Multiparameter fiber optic sensing system for monitoring enhanced geothermal systems

    SciTech Connect (OSTI)

    William A. Challener

    2014-12-04T23:59:59.000Z

    The goal of this project was to design, fabricate and test an optical fiber cable which supports multiple sensing modalities for measurements in the harsh environment of enhanced geothermal systems. To accomplish this task, optical fiber was tested at both high temperatures and strains for mechanical integrity, and in the presence of hydrogen for resistance to darkening. Both single mode (SM) and multimode (MM) commercially available optical fiber were identified and selected for the cable based on the results of these tests. The cable was designed and fabricated using a tube-within-tube construction containing two MM fibers and one SM fiber, and without supporting gel that is not suitable for high temperature environments. Commercial fiber optic sensing instruments using Raman DTS (distributed temperature sensing), Brillouin DTSS (distributed temperature and strain sensing), and Raleigh COTDR (coherent optical time domain reflectometry) were selected for field testing. A microelectromechanical systems (MEMS) pressure sensor was designed, fabricated, packaged, and calibrated for high pressure measurements at high temperatures and spliced to the cable. A fiber Bragg grating (FBG) temperature sensor was also spliced to the cable. A geothermal well was selected and its temperature and pressure were logged. The cable was then deployed in the well in two separate field tests and measurements were made on these different sensing modalities. Raman DTS measurements were found to be accurate to ���±5���°C, even with some residual hydrogen darkening. Brillouin DTSS measurements were in good agreement with the Raman results. The Rayleigh COTDR instrument was able to detect some acoustic signatures, but was generally disappointing. The FBG sensor was used to determine the effects of hydrogen darkening, but drift over time made it unreliable as a temperature or pressure sensor. The MEMS sensor was found to be highly stable and accurate to better than its 0.1% calibration.

  11. OFDR DISTRIBUTED TEMPERATURE AND STRAIN MEASUREMENTS WITH OPTICAL FIBRE SENSING CABLES: APPLICATION TO DRAIN

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    sodium coolant fast breeder reactor in current dismantling). Measurements have been performed during measurements, have been qualified and afterwards installed along a sodium drain line at Superphénix NPP (liquid capacity along a single optical fibre. 1 SCOPE AND MOTIVATION In a liquid metal coolant reactor, all

  12. Shape memory alloy thaw sensors

    DOE Patents [OSTI]

    Shahinpoor, M.; Martinez, D.R.

    1998-04-07T23:59:59.000Z

    A sensor permanently indicates that it has been exposed to temperatures exceeding a critical temperature for a predetermined time period. An element of the sensor made from shape memory alloy changes shape when exposed, even temporarily, to temperatures above the austenitic temperature of the shape memory alloy. The shape change of the SMA element causes the sensor to change between two readily distinguishable states. 16 figs.

  13. Fiber Optical Micro-detectors for Oxygen Sensing in Power Plants

    SciTech Connect (OSTI)

    Gregory L. Baker; Ruby N. Ghosh; D.J. Osborn; Po Zhang

    2006-06-30T23:59:59.000Z

    A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. Our approach towards immobilizing the potassium salt of the molybdenum cluster, K{sub 2}Mo{sub 6}Cl{sub 14}, at the far end of an optical fiber is to embed the cluster in a thermally cured sol-gel matrix particle. This particle-in-binder approach affords fibers with greatly improved mechanical properties, as compared to previous approaches. The sensor was characterized in 2-21% gas phase oxygen at 40, 70 and 100 C. These are promising results for a high temperature fiber optical oxygen sensor based on molybdenum chloride clusters.

  14. Visibility of cold atomic gases in optical lattices for finite temperatures

    SciTech Connect (OSTI)

    Hoffmann, Alexander [Arnold Sommerfeld Center, Ludwig Maximilian Universitaet, Theresienstrasse 37, 80333 Muenchen (Germany); Pelster, Axel [Fachbereich Physik, Universitaet Duisburg-Essen, Lotharstrasse 1, 47048 Duisburg (Germany); Fachbereich Physik, Freie Universitaet Berlin, Arnimallee 14, 14195 Berlin (Germany)

    2009-05-15T23:59:59.000Z

    In nearly all experiments with ultracold atoms time-of-flight pictures are the only data available. In this paper we present an analytical strong-coupling calculation for those time-of-flight pictures of bosons in a three-dimensional optical lattice in the Mott phase. This allows us to determine the visibility, which quantifies the contrast of peaks in the time-of-flight pictures, and we suggest how to use it as a thermometer.

  15. BetaScint{trademark} fiber-optic sensor for detecting strontium-90 and uranium-238 in soil. Innovative technology summary report

    SciTech Connect (OSTI)

    NONE

    1998-12-01T23:59:59.000Z

    Accurate measurements of radioactivity in soils contaminated with Strontium-90 (Sr-90) or Uranium-238 (U-238) are essential for many DOE site remediation programs. These crucial measurements determine if excavation and soil removal is necessary, where remediation efforts should be focused, and/or if a site has reached closure. Measuring soil contamination by standard EPA laboratory methods typically takes a week (accelerated analytical test turnaround) or a month (standard analytical test turnaround). The time delay extends to operations involving heavy excavation equipment and associated personnel which are the main costs of remediation. This report describes an application of the BetaScint{trademark} fiber-optic sensor that measures Sr-90 or U-238 contamination in soil samples on site in about 20 minutes, at a much lower cost than time-consuming laboratory methods, to greatly facilitate remediation. This report describes the technology, its performance, its uses, cost, regulatory and policy issues, and lessons learned.

  16. In-situ, Real-Time Monitoring of Mechanical and Chemical Structure Changes in a V2O5 Battery Electrode Using a MEMS Optical Sensor

    SciTech Connect (OSTI)

    Jung, H. [University of Maryland; Gerasopoulos, K. [University of Maryland; Gnerlich, Markus [University of Maryland; Talin, A. Alec [Sandia National Laboratories; Ghodssi, Reza [University of Maryland

    2014-06-01T23:59:59.000Z

    This work presents the first demonstration of a MEMS optical sensor for in-situ, real-time monitoring of both mechanical and chemical structure evolutions in a V2O5 lithium-ion battery (LIB) cathode during battery operation. A reflective membrane forms one side of a Fabry-Perot (FP) interferometer, while the other side is coated with V2O5 and exposed to electrolyte in a half-cell LIB. Using one microscope and two laser sources, both the induced membrane deflection and the corresponding Raman intensity changes are observed during lithium cycling. Results are in good agreement with the expected mechanical behavior and disorder change of the V2O5 layers, highlighting the significant potential of MEMS as enabling tools for advanced scientific investigations.

  17. Development of an Integrated Raman and Turbidity Fiber Optic Sensor for the In-Situ Analysis of High Level Nuclear Waste - 13532

    SciTech Connect (OSTI)

    Gasbarro, Christina; Bello, Job [EIC Laboratories, Inc., 111 Downey St., Norwood, MA, 02062 (United States)] [EIC Laboratories, Inc., 111 Downey St., Norwood, MA, 02062 (United States); Bryan, Samuel; Lines, Amanda; Levitskaia, Tatiana [Pacific Northwest National Laboratory, PO Box 999, Richland, WA, 99352 (United States)] [Pacific Northwest National Laboratory, PO Box 999, Richland, WA, 99352 (United States)

    2013-07-01T23:59:59.000Z

    Stored nuclear waste must be retrieved from storage, treated, separated into low- and high-level waste streams, and finally put into a disposal form that effectively encapsulates the waste and isolates it from the environment for a long period of time. Before waste retrieval can be done, waste composition needs to be characterized so that proper safety precautions can be implemented during the retrieval process. In addition, there is a need for active monitoring of the dynamic chemistry of the waste during storage since the waste composition can become highly corrosive. This work describes the development of a novel, integrated fiber optic Raman and light scattering probe for in situ use in nuclear waste solutions. The dual Raman and turbidity sensor provides simultaneous chemical identification of nuclear waste as well as information concerning the suspended particles in the waste using a common laser excitation source. (authors)

  18. Development of an Integrated Raman and Turbidity Fiber Optic Sensor for the In-Situ Analysis of High Level Nuclear Waste

    SciTech Connect (OSTI)

    Gasbarro, Christina; Bello, Job M.; Bryan, Samuel A.; Lines, Amanda M.; Levitskaia, Tatiana G.

    2013-02-24T23:59:59.000Z

    Stored nuclear waste must be retrieved from storage, treated, separated into low- and high-level waste streams, and finally put into a disposal form that effectively encapsulates the waste and isolates it from the environment for a long period of time. Before waste retrieval can be done, waste composition needs to be characterized so that proper safety precautions can be implemented during the retrieval process. In addition, there is a need for active monitoring of the dynamic chemistry of the waste during storage since the waste composition can become highly corrosive. This work describes the development of a novel, integrated fiber optic Raman and light scattering probe for in situ use in nuclear waste solutions. The dual Raman and turbidity sensor provides simultaneous chemical identification of nuclear waste as well as information concerning the suspended particles in the waste using a common laser excitation source.

  19. Polymer-Ceramic MEMS Bimorphs as Thermal Infrared Sensors

    E-Print Network [OSTI]

    Warren, Clinton Gregory

    2010-01-01T23:59:59.000Z

    the testing and evaluation of sensors by both optical and4: Results and Evaluation The results of sensor fabrication,of testing and evaluation. A double beam sensor which

  20. A Distributed Fiber Optic Sensor Network for Online 3-D Temperature and Neutron Fluence Mapping in a VHTR Environment

    SciTech Connect (OSTI)

    Tsvetkov, Pavel; Dickerson, Bryan; French, Joseph; McEachern, Donald; Ougouag, Abderrafi

    2014-04-30T23:59:59.000Z

    Robust sensing technologies allowing for 3D in-core performance monitoring in real time are of paramount importance for already established LWRs to enhance their reliability and availability per year, and therefore, to further facilitate their economic competitiveness via predictive assessment of the in-core conditions.

  1. Volume 171,number I,2 CHEMICAL PHYSICS LETTERS 27 July 1990 High temperature optical dephasing mechanism

    E-Print Network [OSTI]

    Fayer, Michael D.

    ,11,13,19,20,24-261. This is the time regime where tunnelling two-level systems (TLS) control the dynamics [27,28]. The TLS model the power law is observed. Dephasing data on a number of systems above z 5 K are fit well to a model times are identical and individual decays at the same temperature from the two systems

  2. Effect of optical pumping on the refractive index and temperature in the core of active fibre

    SciTech Connect (OSTI)

    Gainov, V V; Ryabushkin, Oleg A [V.A.Kotel'nikov Institute of Radio Engineering and Electronics, Fryazino Branch, Russian Academy of Sciences, Fryazino, Moscow Region (Russian Federation)

    2011-09-30T23:59:59.000Z

    This paper examines the refractive index change (RIC) induced in the core of Yb{sup 3+}-doped active silica fibres by pulsed pumping. RIC kinetic measurements with a Mach - Zehnder interferometer make it possible to separately assess the contributions of the electronic and thermal mechanisms to the RIC and evaluate temperature nonuniformities in the fibre.

  3. Electric field and temperature measurement using ultra wide bandwidth pigtailed electro-optic probes

    E-Print Network [OSTI]

    Boyer, Edmond

    .1364/AO.47.002470 #12;2 Introduction In the field of high power microwave (HPM) measurements, ultra wideHz-GHz frequency range) and allowing getting simultaneously one specific component of the HPM E field and the probe determining the energy of a single shot HPM signal by measuring the temperature increase of an EO probe

  4. Multifunctional Nanowire/film Composites based Bi-modular Sensors for In-situ and Real-time High Temperature Gas Detection

    SciTech Connect (OSTI)

    Gao, Pu-Xian; Lei, Yu

    2013-06-01T23:59:59.000Z

    This final report to the Department of Energy/National Energy Technology Laboratory for DE-FE0000870 covers the period from 2009 to June, 2013 and summarizes the main research accomplishments, which can be divided in sensing materials innovation, bimodular sensor demonstration, and new understanding and discoveries. As a matter of fact, we have successfully completed all the project tasks in June 1, 2013, and presented the final project review presentation on the 9th of July, 2013. Specifically, the major accomplishments achieved in this project include: 1) Successful development of a new class of high temperature stable gas sensor nanomaterials based on composite nano-array strategy in a 3D or 2D fashion using metal oxides and perovskite nanostructures. 2) Successful demonstration of bimodular nanosensors using 2D nanofibrous film and 3D composite nanowire arrays using electrical resistance mode and electrochemical electromotive force mode. 3) Series of new discoveries and understandings based on the new composite nanostructure platform toward enhancing nanosensor performance in terms of stability, selectivity, sensitivity and mass flux sensing. In this report, we highlight some results toward these accomplishments.

  5. A new sensor concept for simultaneous measurement of pressure, temperature and thickness of plate structures using modified wave propagation theory

    E-Print Network [OSTI]

    Lo, Tzu-Wei

    2005-11-01T23:59:59.000Z

    -Acousto Photonic Non-Destructive Evaluation (TAP-NDE) is employed to remotely initiate and acquire interrogating ultrasonic waves. Parameters including pressure, temperature and plate thickness are determined through exploring the dispersion features...

  6. Enhancement of the resolution of full-field optical coherence tomography by using a colour image sensor

    SciTech Connect (OSTI)

    Kalyanov, A L; Lychagov, V V; Smirnov, I V; Ryabukho, V P [N.G. Chernyshevsky Saratov State University, Saratov (Russian Federation)

    2013-08-31T23:59:59.000Z

    The influence of white balance in a colour image detector on the resolution of a full-field optical coherence tomograph (FFOCT) is studied. The change in the interference pulse width depending on the white balance tuning is estimated in the cases of a thermal radiation source (incandescent lamp) and a white light emitting diode. It is shown that by tuning white balance of the detector in a certain range, the FFOCT resolution can be increased by 20 % as compared to the resolution, attained with the use of a monochrome detector. (optical coherence tomography)

  7. Multi-Sensor Fusion of Electro-Optic and Infrared Signals for High Resolution Visible Images: Part II

    E-Print Network [OSTI]

    of high resolution and low noise level, but they cannot reflect information about the temperature the properties of low resolution and high noise level, but IR images can reflect information about temperature variation of objects in the daytime via high-resolution EO images. The proposed novel framework

  8. Ris-PhD-19(EN) Self Calibrating Interferometric Sensor

    E-Print Network [OSTI]

    Interferometric Sensor Department: Optics and Plasma Research Department Risø-PhD-19(EN) January 2006 This thesis

  9. Gas sensor

    DOE Patents [OSTI]

    Schmid, Andreas K.; Mascaraque, Arantzazu; Santos, Benito; de la Figuera, Juan

    2014-09-09T23:59:59.000Z

    A gas sensor is described which incorporates a sensor stack comprising a first film layer of a ferromagnetic material, a spacer layer, and a second film layer of the ferromagnetic material. The first film layer is fabricated so that it exhibits a dependence of its magnetic anisotropy direction on the presence of a gas, That is, the orientation of the easy axis of magnetization will flip from out-of-plane to in-plane when the gas to be detected is present in sufficient concentration. By monitoring the change in resistance of the sensor stack when the orientation of the first layer's magnetization changes, and correlating that change with temperature one can determine both the identity and relative concentration of the detected gas. In one embodiment the stack sensor comprises a top ferromagnetic layer two mono layers thick of cobalt deposited upon a spacer layer of ruthenium, which in turn has a second layer of cobalt disposed on its other side, this second cobalt layer in contact with a programmable heater chip.

  10. Thermal microphotonic sensor and sensor array

    DOE Patents [OSTI]

    Watts, Michael R. (Albuquerque, NM); Shaw, Michael J. (Tijeras, NM); Nielson, Gregory N. (Albuquerque, NM); Lentine, Anthony L. (Albuquerque, NM)

    2010-02-23T23:59:59.000Z

    A thermal microphotonic sensor is disclosed for detecting infrared radiation using heat generated by the infrared radiation to shift the resonant frequency of an optical resonator (e.g. a ring resonator) to which the heat is coupled. The shift in the resonant frequency can be determined from light in an optical waveguide which is evanescently coupled to the optical resonator. An infrared absorber can be provided on the optical waveguide either as a coating or as a plate to aid in absorption of the infrared radiation. In some cases, a vertical resonant cavity can be formed about the infrared absorber to further increase the absorption of the infrared radiation. The sensor can be formed as a single device, or as an array for imaging the infrared radiation.

  11. Abstract--Mobile devices are becoming increasingly sophisti-cated and now incorporate many diverse and powerful sensors.

    E-Print Network [OSTI]

    Weiss, Gary

    sensors, direc- tion sensors (compasses), and acceleration sensors. In this paper we describe and evaluate diverse and powerful sensors. The latest generation of smart phones is especially laden with sensors, including GPS sensors, vision sensors (cameras), audio sensors (microphones), light sensors, temperature

  12. Multi-channel optical pyrometer for sub-nanosecond temperature measurements at NDCX-I/II

    SciTech Connect (OSTI)

    Ni, P.A.; Bieniosek, F.M.; Waldron, W.L.

    2011-04-13T23:59:59.000Z

    We present a detailed technical description of a fast multi-channel pyrometer designed for warm-dense-matter (WDM) experiments with intense heavy ion beams at the neutralized-drift-compression-experiment linear accelerator (NDCX-I/II) at Lawrence Berkeley National Laboratory (LBNL). The unique features of the described instrument are its sub-nanosecond temporal resolution (100 ps rise-time) and a broad range, 1,500 K - 12,000 K of measurable brightness temperatures in the visible and near-infrared regions of the spectrum. The working scheme, calibration procedure, experimental data obtained with the pyrometer and future applications are presented.

  13. Algal biomass and sea surface temperature in the Mediterranean Basin Intercomparison of data from various satellite sensors, and implications for

    E-Print Network [OSTI]

    Bricaud, Annick

    Algal biomass and sea surface temperature in the Mediterranean Basin Intercomparison of data from and to increasing anthropogenic inputs, is an appropriate test site for observing the evolution of algal biomass progress in the knowledge of spatial and temporal variations in algal biomass in various regions

  14. Zero-temperature phase diagram of Bose-Fermi gaseous mixtures in optical lattices

    SciTech Connect (OSTI)

    Polak, T. P.; Kopec, T. K. [Faculty of Physics, Adam Mickiewicz University of Poznan, Umultowska 85, PL-61-614 Poznan (Poland); Institute for Low Temperatures and Structure Research, Polish Academy of Sciences, Post Office Box 1410, PL-50-950 Wroclaw 2 (Poland)

    2010-04-15T23:59:59.000Z

    We study the ground-state phase diagram of a mixture of bosonic and fermionic cold atoms confined on two- and three-dimensional optical lattices. The coupling between bosonic fluctuations and fermionic atoms can be attractive or repulsive and has similarities with electron-phonon coupling in crystals. We investigate behavior of the mixtures in the limit, where the Bogoliubov sound velocity that dictates bosonic dynamics is comparable to the Fermi velocity, hence the retardation effects are an important part of the physics. The dynamic Lindhard response function of the fermionic density to changes in the bosonic number of particles above some critical frequency can alter the sign, and consequently the interspecies interaction between particles becomes repulsive in contrast to the static limit (instantaneous and always attractive). Considering the above, we show that the structure of the phase diagrams crucially depends on the difference in masses of the bosons and fermions. We discuss the situations where integrating out the fermionic field provides an additional interaction that can decrease or increase bosonic coherence.

  15. Ultrafast (370 GHz bandwidth) p-i-n traveling wave photodetector using low-temperature-grown GaAs

    E-Print Network [OSTI]

    Bowers, John

    measured with a thermocouple temperature sensor and then in situ annealed at 590 °C for 10 min. We found photodetectors utilizing low-temperature-grown GaAs as the absorption layer. The electro-optically measured-efficiency product. By dis- tributing the RC elements and impedance matching to exter- nal circuits, both p

  16. Microscale autonomous sensor and communications module

    DOE Patents [OSTI]

    Okandan, Murat; Nielson, Gregory N

    2014-03-25T23:59:59.000Z

    Various technologies pertaining to a microscale autonomous sensor and communications module are described herein. Such a module includes a sensor that generates a sensor signal that is indicative of an environmental parameter. An integrated circuit receives the sensor signal and generates an output signal based at least in part upon the sensor signal. An optical emitter receives the output signal and generates an optical signal as a function of the output signal. An energy storage device is configured to provide power to at least the integrated circuit and the optical emitter, and wherein the module has a relatively small diameter and thickness.

  17. Core-shell multi-quantum wells in ZnO / ZnMgO nanowires with high optical efficiency at room temperature

    E-Print Network [OSTI]

    Thierry, Robin; Jouneau, Pierre-Henri; Ferret, Pierre; Feuillet, Guy; 10.1088/0957-4484/23/8/085705

    2013-01-01T23:59:59.000Z

    Nanowire-based light-emitting devices require multi-quantum well heterostructures with high room temperature optical efficiencies. We demonstrate that such efficiencies can be attained through the use of ZnO/Zn(1-x)MgxO core shell quantum well heterostructures grown by metal organic vapour phase epitaxy. Varying the barrier Mg concentration from x=0.15 to x=0.3 leads to the formation of misfit induced dislocations in the multi quantum wells. Correlatively, temperature dependant photoluminescence reveals that the radial well luminescence intensity decreases much less rapidly with increasing temperature for the lower Mg concentration. Indeed, about 54% of the 10K intensity is retained at room temperature with x=0.15, against 2% with x=0.30. Those results open the way to the realization of high optical efficiency nanowire-based light emitting diodes.

  18. An integrated quantum photonic sensor based on Hong-Ou-Mandel interference

    E-Print Network [OSTI]

    Sahar Basiri-Esfahani; Casey R. Myers; Ardalan Armin; Joshua Combes; Gerard J. Milburn

    2015-06-10T23:59:59.000Z

    Photonic-crystal-based integrated optical systems have been used for a broad range of sensing applications with great success. This has been motivated by several advantages such as high sensitivity, miniaturization, remote sensing, selectivity and stability. Many photonic crystal sensors have been proposed with various fabrication designs that result in improved optical properties. In parallel, integrated optical systems are being pursued as a platform for photonic quantum information processing using linear optics and Fock states. Here we propose a novel integrated Fock state optical sensor architecture that can be used for force, refractive index and possibly local temperature detection. In this scheme, two coupled cavities behave as an "effective beam splitter". The sensor works based on fourth order interference (the Hong-Ou-Mandel effect) and requires a sequence of single photon pulses and consequently has low pulse power. Changes in the parameter to be measured induce variations in the effective beam splitter reflectivity and result in changes to the visibility of interference. We demonstrate this generic scheme in coupled L3 photonic crystal cavities as an example and find that this system, which only relies on photon coincidence detection and does not need any spectral resolution, can estimate forces as small as $10^{-7}$ Newtons and can measure one part per million change in refractive index using a very low input power of $10^{-10}$W. Thus linear optical quantum photonic architectures can achieve comparable sensor performance to semiclassical devices.

  19. Sensor Network Demonstration for In Situ Decommissioning - 13332

    SciTech Connect (OSTI)

    Lagos, L.; Varona, J.; Awwad, A. [Applied Research Center, Florida International University, 10555 West Flagler Street, Suite 2100, Miami, FL 33174 (United States)] [Applied Research Center, Florida International University, 10555 West Flagler Street, Suite 2100, Miami, FL 33174 (United States); Rivera, J.; McGill, J. [Department of Energy - DOE, Environmental Management Office (United States)] [Department of Energy - DOE, Environmental Management Office (United States)

    2013-07-01T23:59:59.000Z

    Florida International University's (FIU's) Applied Research Center is currently supporting the Department of Energy's (DOE) Environmental Management Office of D and D and Facility Engineering program. FIU is supporting DOE's initiative to improve safety, reduce technical risks, and limit uncertainty within D and D operations by identifying technologies suitable to meet specific facility D and D requirements, assessing the readiness of those technologies for field deployment, and conducting feasibility studies and large scale demonstrations of promising technologies. During FY11, FIU collaborated with Savannah River National Laboratory in the development of an experimental test site for the demonstration of multiple sensor systems for potential use in the in situ decommissioning process. In situ decommissioning is a process in which the above ground portion of a facility is dismantled and removed, and the underground portion is filled with a cementious material such as grout. In such a scenario, the question remains on how to effectively monitor the structural health of the grout (cracking, flexing, and sinking), as well as track possible migration of contaminants within and out of the grouted monolith. The right types of sensors can aid personnel in better understanding the conditions within the entombed structure. Without sensors embedded in and around the monolith, it will be very difficult to estimate structural integrity and contaminant transport. Yet, to fully utilize the appropriate sensors and the provided data, their performance and reliability must be evaluated outside a laboratory setting. To this end, a large scale experimental setup and demonstration was conducted at FIU. In order to evaluate a large suite of sensor systems, FIU personnel designed and purchased a pre-cast concrete open-top cube, which served as a mock-up of an in situ DOE decommissioned facility. The inside of the cube measures 10 ft x 10 ft x 8 ft. In order to ensure that the individual sensors would be immobilized during the grout pouring activities, a set of nine sensor racks were designed. The 270 sensors provided by Idaho National Laboratory (INL), Mississippi State University (MSU), University of Houston (UH), and University of South Carolina (USC) were secured to these racks based on predetermined locations. Once sensor racks were installed inside the test cube, connected and debugged, approximately 32 cubic yards of special grout material was used to entomb the sensors. MSU provided and demonstrated four types of fiber loop ring-down (FLR) sensors for detection of water, temperature, cracks, and movement of fluids. INL provided and demonstrated time differenced 3D electrical resistivity tomography (ERT), advanced tensiometers for moisture content, and thermocouples for temperature measurements. University of Houston provided smart aggregate (SA) sensors, which detect crack severity and water presence. An additional UH sensor system demonstrated was a Fiber Bragg Grating (FBG) fiber optic system measuring strain, presence of water, and temperature. USC provided a system which measured acoustic emissions during cracking, as well as temperature and pH sensors. All systems were connected to a Sensor Remote Access System (SRAS) data networking and collection system designed, developed and provided by FIU. The purpose of SRAS was to collect and allow download of the raw sensor data from all the sensor system, as well as allow upload of the processed data and any analysis reports and graphs. All this information was made available to the research teams via the Deactivation and Decommissioning Knowledge Management and Information Tool (D and D KM-IT). As a current research effort, FIU is performing an energy analysis, and transferring several sensor systems to a Photovoltaic (PV) System to continuously monitor energy consumption parameters and overall power demands. Also, One final component of this research is focusing on developing an integrated data network to capture, log and analyze sensor system data in near real time from a single inte

  20. FIBER OPTICAL MICRO-DETECTORS FOR OXYGEN SENSING IN POWER PLANTS

    SciTech Connect (OSTI)

    Gregory L. Baker; Ruby N. Ghosh; D.J. Osborn III

    2004-07-01T23:59:59.000Z

    A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. Alkali salts of Mo{sub 6}Cl{sub 12} were synthesized and heated to 280 C for one hour in air. Optical measurements of the thermally treated material confirm the potential of the salts as lumophores in high temperature fiber optic sensors. In addition sol-gel films containing Mo{sub 6}Cl{sub 12} were dip coated on quartz substrates and heated at 200 C for one hour. Conditions were developed for successfully immobilizing monomeric complexes that are compatible with sol-gel processing.

  1. Size-dependent shifts of the Néel temperature and optical band-gap in NiO nanoparticles

    SciTech Connect (OSTI)

    Thota, Subhash, E-mail: mseehra@wvu.edu, E-mail: subhasht@iitg.ac.in [Department of Physics, Indian Institute of Technology, Guwahati, Assam 781039 (India); Shim, J. H.; Seehra, M. S., E-mail: mseehra@wvu.edu, E-mail: subhasht@iitg.ac.in [Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2013-12-07T23:59:59.000Z

    Bulk NiO is a well-known antiferromagnet with Neel temperature T{sub N}(?)?=?524?K and an optical band-gap E{sub g}?=?4.3?eV. With decrease in particle size D from 40?nm to 4?nm of NiO, systematic changes of T{sub N} and E{sub g} are observed and discussed here. From magnetic measurements, the changes in T{sub N} with D are found to fit finite-size scaling equation T{sub N}(D)?=?T{sub N}(?) [1 ? (?{sub o}/D){sup ?}] with ??=?3.2?±?0.5 and ?{sub o}?=?3.2?±?0.2?nm, in good agreement with the predictions for a Heisenberg system. The observed blue shifts of E{sub g} with decrease in D reaching E{sub g}?=?5.12?eV for D???4?nm are likely due to quantum confinement and non-stoichiometry.

  2. Aerogel Growth, Optical Birefringence Characterization, and Use in Ultra Low Temperature Superfluid 3 He Experiments Senior Honors Thesis

    E-Print Network [OSTI]

    Kent Shirer; Advisor Prof; William Halperin

    Superfluid 3 He has important implications in studying condensed matter physics, specifically in its phases at very low temperatures. The understanding of these phases not only expands our knowledge of 3 He itself, but is also a paradigm for recently discovered unconventional superconductors such as strontium ruthenate (SrRuO3) and uranium platinum three (UPt3). Superfluid 3 He’s relation to superconductors is not in its pure form, but in dirty superfluid 3 He, where impurities from external sources are present. This is because real superconductors, unlike ideal ones, contain unavoidable impurities. In 3 He, however, we can control the number of impurities and how they are distributed in space. These impurities are introduced by filling the extremely porous structure of silica aerogel with 3 He. The aerogel pore size is on a scale that causes 3 He particles to scatter, similar to the behavior brought about by impurities in other unconventional systems. The microstructure of the aerogel plays an integral role in the modification of the 3 He system. Presented here are aerogel growth methods developed to control this microstructure, and the employment of optical birefringence as an aerogel characterization technique. Introduction and Motivation

  3. Optical absorption measurement system

    DOE Patents [OSTI]

    Draggoo, Vaughn G. (Livermore, CA); Morton, Richard G. (San Diego, CA); Sawicki, Richard H. (Pleasanton, CA); Bissinger, Horst D. (Livermore, CA)

    1989-01-01T23:59:59.000Z

    The system of the present invention contemplates a non-intrusive method for measuring the temperature rise of optical elements under high laser power optical loading to determine the absorption coefficient. The method comprises irradiating the optical element with a high average power laser beam, viewing the optical element with an infrared camera to determine the temperature across the optical element and calculating the absorption of the optical element from the temperature.

  4. Structural, Electrical, and Optical Properties of SnO2:Sb Films Prepared on Flexible Substrate at Room Temperature

    E-Print Network [OSTI]

    Boo, Jin-Hyo

    , and solar cells.1­5) The increased utilization of many transparent electrodes has recently accelerated for application in various fields such as gas sensors, optoelec- tronic devices, flat panel displays, heat mirrors

  5. Fluorescent fluid interface position sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D.

    2004-02-17T23:59:59.000Z

    A new fluid interface position sensor has been developed, which is capable of optically determining the location of an interface between an upper fluid and a lower fluid, the upper fluid having a larger refractive index than a lower fluid. The sensor functions by measurement, of fluorescence excited by an optical pump beam which is confined within a fluorescent waveguide where that waveguide is in optical contact with the lower fluid, but escapes from the fluorescent waveguide where that waveguide is in optical contact with the upper fluid.

  6. Shot-noise-limited magnetometer with sub-pT sensitivity at room temperature

    E-Print Network [OSTI]

    Vito Giovanni Lucivero; Pawel Anielski; Wojciech Gawlik; Morgan W. Mitchell

    2014-11-20T23:59:59.000Z

    We report a photon shot-noise-limited (SNL) optical magnetometer based on amplitude modulated optical rotation using a room-temperature $^{85}$Rb vapor in a cell with anti-relaxation coating. The instrument achieves a room-temperature sensitivity of $70$ fT/$\\sqrt{\\mathrm{Hz}}$ at $7.6$ $\\mu$T. Experimental scaling of noise with optical power, in agreement with theoretical predictions, confirms the SNL behaviour from $5$ $\\mu$T to $75$ $\\mu$T. The combination of best-in-class sensitivity and SNL operation makes the system a promising candidate for application of squeezed light to a state-of-the-art atomic sensor.

  7. Distributed optical fiber vibration sensing 

    E-Print Network [OSTI]

    Yu, Hui

    2001-01-01T23:59:59.000Z

    This thesis presents a distributed optical fiber vibration sensor. The purpose of this sensing system is to monitor, in real time, the status of railcars by burying an optical fiber underground beside the rails. Using a coherent homodyne technique...

  8. An integrated quantum photonic sensor based on Hong-Ou-Mandel interference

    E-Print Network [OSTI]

    Basiri-Esfahani, Sahar; Armin, Ardalan; Combes, Joshua; Milburn, Gerard J

    2015-01-01T23:59:59.000Z

    Photonic-crystal-based integrated optical systems have been used for a broad range of sensing applications with great success. This has been motivated by several advantages such as high sensitivity, miniaturization, remote sensing, selectivity and stability. Many photonic crystal sensors have been proposed with various fabrication designs that result in improved optical properties. Here we propose a novel multi-purpose sensor architecture that can be used for force, refractive index and possibly local temperature detection. In this scheme, two coupled cavities behave as an "effective beam splitter". The sensor works based on fourth order interference (the Hong-Ou-Mandel effect) and requires a sequence of single photon pulses and consequently has low pulse power. Changes in the parameter to be measured induce variations in the effective beam splitter reflectivity and result in changes to the visibility of interference. We demonstrate this generic scheme in coupled L3 photonic crystal cavities as an example and...

  9. Optically Isolated HVIGBT Based MW Cascade Inverter Building...

    Broader source: Energy.gov (indexed) [DOE]

    Sensor 22.5KV 3" Solid Conductor Sensor 34.5KV Overhead Sensor Pole-Mounted Electro-Optics Benefits for Customer: - Complete Data Acquisition, Processing, Storage (up to 1...

  10. High temperature liquid level sensor

    DOE Patents [OSTI]

    Tokarz, Richard D. (West Richland, WA)

    1983-01-01T23:59:59.000Z

    A length of metal sheathed metal oxide cable is perforated to permit liquid access to the insulation about a pair of conductors spaced close to one another. Changes in resistance across the conductors will be a function of liquid level, since the wetted insulation will have greater electrical conductivity than that of the dry insulation above the liquid elevation.

  11. Influence of growth temperature on electrical, optical, and plasmonic properties of aluminum:zinc oxide films grown by radio frequency magnetron sputtering

    SciTech Connect (OSTI)

    Dondapati, Hareesh; Santiago, Kevin; Pradhan, A. K. [Center for Materials Research, Norfolk State University, 700 Park Avenue, Norfolk, Virginia 23504 (United States)] [Center for Materials Research, Norfolk State University, 700 Park Avenue, Norfolk, Virginia 23504 (United States)

    2013-10-14T23:59:59.000Z

    We have investigated the responsible mechanism for the observation of metallic conductivity at room temperature and metal-semiconductor transition (MST) at lower temperatures for aluminum-doped zinc oxide (AZO) films. AZO films were grown on glass substrates by radio-frequency magnetron sputtering with varying substrate temperatures (T{sub s}). The films were found to be crystalline with the electrical resistivity close to 1.1 × 10{sup ?3} ? cm and transmittance more than 85% in the visible region. The saturated optical band gap of 3.76 eV was observed for the sample grown at T{sub s} of 400 °C, however, a slight decrease in the bandgap was noticed above 400 °C, which can be explained by Burstein–Moss effect. Temperature dependent resistivity measurements of these highly conducting and transparent films showed a MST at ?110 K. The observed metal-like and metal-semiconductor transitions are explained by taking into account the Mott phase transition and localization effects due to defects. All AZO films demonstrate crossover in permittivity from positive to negative and low loss in the near-infrared region, illustrating its applications for plasmonic metamaterials, including waveguides for near infrared telecommunication region. Based on the results presented in this study, the low electrical resistivity and high optical transmittance of AZO films suggested a possibility for the application in the flexible electronic devices, such as transparent conducting oxide film on LEDs, solar cells, and touch panels.

  12. Nuclear sensor signal processing circuit

    DOE Patents [OSTI]

    Kallenbach, Gene A. (Bosque Farms, NM); Noda, Frank T. (Albuquerque, NM); Mitchell, Dean J. (Tijeras, NM); Etzkin, Joshua L. (Albuquerque, NM)

    2007-02-20T23:59:59.000Z

    An apparatus and method are disclosed for a compact and temperature-insensitive nuclear sensor that can be calibrated with a non-hazardous radioactive sample. The nuclear sensor includes a gamma ray sensor that generates tail pulses from radioactive samples. An analog conditioning circuit conditions the tail-pulse signals from the gamma ray sensor, and a tail-pulse simulator circuit generates a plurality of simulated tail-pulse signals. A computer system processes the tail pulses from the gamma ray sensor and the simulated tail pulses from the tail-pulse simulator circuit. The nuclear sensor is calibrated under the control of the computer. The offset is adjusted using the simulated tail pulses. Since the offset is set to zero or near zero, the sensor gain can be adjusted with a non-hazardous radioactive source such as, for example, naturally occurring radiation and potassium chloride.

  13. Waveguide-based Ultrasonic and Far-field Electromagnetic Sensors...

    Office of Environmental Management (EM)

    ultrasonic and farfield electromagnetic sensors to measure key Enhanced Geothermal Systems (EGS) reservoir parameters, including directional temperature, pressure,...

  14. Etalon-induced Baseline Drift And Correction In Atom Flux Sensors Based On Atomic Absorption Spectroscopy

    SciTech Connect (OSTI)

    Du, Yingge; Chambers, Scott A.

    2014-10-20T23:59:59.000Z

    Atom flux sensors based on atomic absorption (AA) spectroscopy are of significant interest in thin film growth as they can provide unobtrusive, element specific, real-time flux sensing and control. The ultimate sensitivity and performance of the sensors are strongly affected by the long-term and short term baseline drift. Here we demonstrate that an etalon effect resulting from temperature changes in optical viewport housings is a major source of signal instability which has not been previously considered or corrected by existing methods. We show that small temperature variations in the fused silica viewports can introduce intensity modulations of up to 1.5%, which in turn significantly deteriorate AA sensor performance. This undesirable effect can be at least partially eliminated by reducing the size of the beam and tilting the incident light beam off the viewport normal.

  15. Gamma-insensitive optical sensor

    DOE Patents [OSTI]

    Kruger, H.W.

    1994-03-15T23:59:59.000Z

    An ultraviolet/visible/infrared gamma-insensitive gas avalanche focal plane array is described comprising a planar photocathode and a planar anode pad array separated by a gas-filled gap and across which is applied an electric potential. Electrons ejected from the photocathode are accelerated sufficiently between collisions with the gas molecules to ionize them, forming an electron avalanche. The gap acts like a proportional counter. The array of anode pad are mounted on the front of an anode plate and are connected to matching contact pads on the back of the anode via feed through wires. Connection of the anode to signal processing electronics is made from the contact pads using standard indium bump techniques, for example. 6 figures.

  16. FIBER OPTICAL MICRO-DETECTORS FOR OXYGEN SENSING IN POWER PLANTS

    SciTech Connect (OSTI)

    Gregory L. Baker; Ruby N. Ghosh; D.J. Osborn III; Po Zhang

    2005-04-01T23:59:59.000Z

    A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. One of the critical materials issues is to demonstrate that the luminescent cluster immobilized in the sol-gel porous support can withstand high temperature. At the same time the sol-gel matrix must have a high permeability to oxygen. Using a potassium salt of the molybdenum clusters, K{sub 2}Mo{sub 6}Cl{sub 14}, we have established the conditions necessary for deposition of optical quality sol-gel films. From spectroscopic measurements of the film we have shown that the cluster luminescence is stable following heat cycling of 54 hours at 200 C. Quenching of a factor of 1.5X between pure nitrogen and 21% oxygen was observed from in-situ measurements of films heated directly at 200 C. An automated system for characterizing fiber optic oxygen sensors up to 220 C with a temporal resolution better than 10 s is under construction. We estimate a signal of 6 x 10{sup 8} photons/s after complete quenching in 21% oxygen. These are promising results for a high temperature fiber optical oxygen sensor based on molybdenum chloride clusters.

  17. Application of Luminescent Materials to Optical Sensing 

    E-Print Network [OSTI]

    Ritter, Sarah C

    2014-09-05T23:59:59.000Z

    Development of sensors for detection of various chemical and biological species is an important and ever-growing field. In particular, optical-based sensors enable a remote, rapid method for continuous or on-demand monitoring. Monitoring humidity...

  18. Small, Inexpensive Combined NOx Sensor and O2 Sensor

    SciTech Connect (OSTI)

    W. N. Lawless; C. F. Clark, Jr.

    2008-09-08T23:59:59.000Z

    It has been successfully demonstrated in this program that a zirconia multilayer structure with rhodium-based porous electrodes performs well as an amperometric NOx sensor. The sensitivity of the sensor bodies operating at 650 to 700 C is large, with demonstrated current outputs of 14 mA at 500 ppm NOx from sensors with 30 layers. The sensor bodies are small (4.5 x 4.2 x 3.1 mm), rugged, and inexpensive. It is projected the sensor bodies will cost $5 - $10 in production. This program has built on another successful development program for an oxygen sensor based on the same principles and sponsored by DOE. This oxygen sensor is not sensitive to NOx. A significant technical hurdle has been identified and solved. It was found that the 100% Rh electrodes oxidize rapidly at the preferred operating temperatures of 650 - 700 C, and this oxidation is accompanied by a volume change which delaminates the sensors. The problem was solved by using alloys of Rh and Pt. It was found that a 10%/90% Rh/Pt alloy dropped the oxidation rate of the electrodes by orders of magnitude without degrading the NOx sensitivity of the sensors, allowing long-term stable operation at the preferred operating temperatures. Degradation in the sensor output caused by temperature cycling was identified as a change in resistance at the junction between the sensor body and the external leads attached to the sensor body. The degradation was eliminated by providing strong mechanical anchors for the wire and processing the junctions to obtain good electrical bonds. The NOx sensors also detect oxygen and therefore the fully-packaged sensor needs to be enclosed with an oxygen sensor in a small, heated zirconia chamber exposed to test gas through a diffusion plug which limits the flow of gas from the outside. Oxygen is pumped from the interior of the chamber to lower the oxygen content and the combination of measurements from the NOx and oxygen sensors yields the NOx content of the gas. Two types of electronic control units were designed and built. One control unit provides independent constant voltages to the NOx and oxygen sensors and reads the current from them (that is, detects the amount of test gas present). The second controller holds the fully-assembled sensor at the desired operating temperature and controllably pumps excess oxygen from the test chamber. While the development of the sensor body was a complete success, the development of the packaging was only partially successful. All of the basic principles were demonstrated, but the packaging was too complex to optimize the operation within the resources of the program. Thus, no fully-assembled sensors were sent to outside labs for testing of cross-sensitivities, response times, etc. Near the end of the program, Sensata Technologies of Attleboro, MA tested the sensor bodies and confirmed the CeramPhysics measurements as indicated in the following attached letter. Sensata was in the process of designing their own packaging for the sensor and performing cross-sensitivity tests when they stopped all sensor development work due to the automotive industry downturn. Recently Ceramatec Inc. of Salt Lake City has expressed an interest in testing the sensor, and other licensing opportunities are being pursued.

  19. Application of an all-solid-state diode-laser-based sensor for carbon monoxide detection by optical absorption in the 4.4 ? 4.8 µm spectral region

    E-Print Network [OSTI]

    Rodolfo, Barron Jimenez

    2005-02-17T23:59:59.000Z

    for operation in harsh combustion environments but much improvement in the sensor design and operation was required. Experiments in near-adiabatic hydrogen/air CO 2 -doped flames were performed featuring two-line thermometry in the 4.8 ?m spectral region... performed in the 0.32 m room temperature gas cell filled with 1010 ppm CO in N 2 at pressures: a) 6.66 kPa and b) 13.33 kPa. GF CO , X CO , and rms noise of the fit are shown for both measured data sets Absorption 1 and 2...

  20. Fabrication and Characterization of Poly(2-Hydroxyethyl Methacrylate) Microparticle Sensors 

    E-Print Network [OSTI]

    Philip, Merene

    2013-04-24T23:59:59.000Z

    Optical biosensors are desired for the monitoring of various biochemical markers, which are relevant indicators in the treatment and diagnosis of diseases. Specifically, luminescence sensors are favorable for optical interrogation since...

  1. The optical applications of 3D sub-wavelength block-copolymer nanostructured functional materials

    E-Print Network [OSTI]

    Poole, Zsolt; Ohodnicki, Paul; Chen, Kevin

    2015-01-01T23:59:59.000Z

    A method to engineer the refractive indices of functional materials (TiO2, ZnO, SnO2, SiO2), by nanostructuring in the deep sub-wavelength regime (optical design techniques such as thin film optimization methods, transformation optics and conformal mapping. Refractive index optimized multi-layer anti-reflection coatings on crystalline silicon, which reduce light reflections from 38% down to ~3% with a wide angular span, are demonstrated with the developed wet processing route. A high temperature oxygen free fiber optic hydrogen sensor realized by accessing nano-engine...

  2. Lump detection with a gelsight sensor

    E-Print Network [OSTI]

    Jia, Xiaodan

    A GelSight sensor is a tactile sensing device comprising a clear elastomeric pad covered with a reflective membrane, coupled with optics to measure the membrane's deformations. When the pad is pressed against an object's ...

  3. Optical analyzer

    DOE Patents [OSTI]

    Hansen, A.D.

    1987-09-28T23:59:59.000Z

    An optical analyzer wherein a sample of particulate matter, and particularly of organic matter, which has been collected on a quartz fiber filter is placed in a combustion tube, and light from a light source is passed through the sample. The temperature of the sample is raised at a controlled rate and in a controlled atmosphere. The magnitude of the transmission of light through the sample is detected as the temperature is raised. A data processor, differentiator and a two pen recorder provide a chart of the optical transmission versus temperature and the rate of change of optical transmission versus temperature signatures (T and D) of the sample. These signatures provide information as to physical and chemical processes and a variety of quantitative and qualitative information about the sample. Additional information is obtained by repeating the run in different atmospheres and/or different rates or heating with other samples of the same particulate material collected on other filters. 7 figs.

  4. A Robust MEMS Based Multi-Component Sensor for 3D Borehole Seismic Arrays

    SciTech Connect (OSTI)

    Paulsson Geophysical Services

    2008-03-31T23:59:59.000Z

    The objective of this project was to develop, prototype and test a robust multi-component sensor that combines both Fiber Optic and MEMS technology for use in a borehole seismic array. The use such FOMEMS based sensors allows a dramatic increase in the number of sensors that can be deployed simultaneously in a borehole seismic array. Therefore, denser sampling of the seismic wave field can be afforded, which in turn allows us to efficiently and adequately sample P-wave as well as S-wave for high-resolution imaging purposes. Design, packaging and integration of the multi-component sensors and deployment system will target maximum operating temperature of 350-400 F and a maximum pressure of 15000-25000 psi, thus allowing operation under conditions encountered in deep gas reservoirs. This project aimed at using existing pieces of deployment technology as well as MEMS and fiber-optic technology. A sensor design and analysis study has been carried out and a laboratory prototype of an interrogator for a robust borehole seismic array system has been assembled and validated.

  5. Optical Measurement Technologies for High Temperature, Radiation Exposure, and Corrosive Environments—Significant Activities and Findings: In-vessel Optical Measurements for Advanced SMRs

    SciTech Connect (OSTI)

    Anheier, Norman C.; Cannon, Bret D.; Qiao, Hong (Amy) [Amy; Suter, Jonathan D.

    2012-09-01T23:59:59.000Z

    Development of advanced Small Modular Reactors (aSMRs) is key to providing the United States with a sustainable, economically viable, and carbon-neutral energy source. The aSMR designs have attractive economic factors that should compensate for the economies of scale that have driven development of large commercial nuclear power plants to date. For example, aSMRs can be manufactured at reduced capital costs in a factory and potentially shorter lead times and then be shipped to a site to provide power away from large grid systems. The integral, self-contained nature of aSMR designs is fundamentally different than conventional reactor designs. Future aSMR deployment will require new instrumentation and control (I&C) architectures to accommodate the integral design and withstand the extreme in-vessel environmental conditions. Operators will depend on sophisticated sensing and machine vision technologies that provide efficient human-machine interface for in-vessel telepresence, telerobotic control, and remote process operations. The future viability of aSMRs is dependent on understanding and overcoming the significant technical challenges involving in-vessel reactor sensing and monitoring under extreme temperatures, pressures, corrosive environments, and radiation fluxes

  6. Optical caliper with compensation for specimen deflection and method

    DOE Patents [OSTI]

    Bernacki, B.E.

    1997-12-09T23:59:59.000Z

    An optical non-contact profilometry system and method provided by an optical caliper with matched optical sensors that are arranged conjugate to each other so that the surface profile and thickness of an article can be measured without using a fixed reference surface and while permitting the article to deflect in space within the acquisition range of the optical sensors. The output signals from the two optical sensors are algebraically added to compensate for any such deflection of the article and provide a so compensated signal, the balance and sign of which provides a measurement of the actual thickness of the article at the optical sensors. 2 figs.

  7. Optical caliper with compensation for specimen deflection and method

    DOE Patents [OSTI]

    Bernacki, Bruce E. (Knoxville, TN)

    1997-01-01T23:59:59.000Z

    An optical non-contact profilometry system and method provided by an optical caliper with matched optical sensors that are arranged conjugate to each other so that the surface profile and thickness of an article can be measured without using a fixed reference surface and while permitting the article to deflect in space within the acquisition range of the optical sensors. The output signals from the two optical sensors are algebraically added to compensate for any such deflection of the article and provide a so compensated signal, the balance and sign of which provides a measurement of the actual thickness of the article at the optical sensors.

  8. Determination of the electron temperature by optical emission spectroscopy in a 13.56 MHz dusty methane plasma: Influence of the power

    SciTech Connect (OSTI)

    Massereau-Guilbaud, Veronique; Geraud-Grenier, Isabelle; Plain, Andre [Groupe de Recherches sur l'Energetique des Milieux Ionises (GREMI), UMR 6606 CNRS/Universite d'Orleans, Faculte des Sciences, Site de Bourges, rue Gaston Berger, BP 4043, 18028 Bourges Cedex (France)

    2009-12-01T23:59:59.000Z

    Optical emission spectroscopy is applied to the study of a radiofrequency (13.56 MHz) discharge in methane used to obtain hydrogenated carbon films and particles. The methane dissociation allows the creation of species in the plasma bulk as H{sub 2}, H, and CH. The emission lines of these species are studied as a function of time and of incident rf power. The electron temperature is determined from the two line radiance ratio method and the corona balance model using the Balmer lines (H{sub alpha}, H{sub beta}, and H{sub gamma}). The incident rf power enhancement in the range 40-120 W leads to the increase in the emission line intensities as the electron temperature decreases. The temporal variations of CH and hydrogen emission lines, of the dc self-bias voltage, and of the electron temperature are correlated both with the particle behavior and growth in the plasma, and with the coating that grows onto the powered electrode.

  9. The effects of high temperature processing on the structural and optical properties of oxygenated CdS window layers in CdTe solar cells

    SciTech Connect (OSTI)

    Paudel, Naba R.; Grice, Corey R.; Xiao, Chuanxiao; Yan, Yanfa [Department of Physics and Astronomy, and Wright Center for Photovoltaics Innovation and Commercialization, The University of Toledo, Toledo, Ohio 43606 (United States)

    2014-07-28T23:59:59.000Z

    High efficiency CdTe solar cells typically use oxygenated CdS (CdS:O) window layers. We synthesize CdS:O window layers at room temperature (RT) and 270?°C using reactive sputtering. The band gaps of CdS:O layers deposited at RT increase when O{sub 2}/(O{sub 2}?+?Ar) ratios in the deposition chamber increase. On the other hand, the band gaps of CdS:O layers deposited at 270?°C decrease as the O{sub 2}/(O{sub 2}?+?Ar) ratios increase. Interestingly, however, our high temperature closed-space sublimation (CSS) processed CdTe solar cells using CdS:O window layers deposited at RT and 270?°C exhibit very similar cell performance, including similar short-circuit current densities. To understand the underlying reasons, CdS:O thin films deposited at RT and 270?°C are annealed at temperatures that simulate the CSS process of CdTe deposition. X-ray diffraction, atomic force microscopy, and UV-visible light absorption spectroscopy characterization of the annealed films reveals that the CdS:O films deposited at RT undergo grain regrowth and/or crystallization and exhibit reduced band gaps after the annealing. Our results suggest that CdS:O thin films deposited at RT and 270?°C should exhibit similar optical properties after the deposition of CdTe layers, explaining the similar cell performance.

  10. Thermal sensor with an improved coating

    DOE Patents [OSTI]

    LaDelfe, Peter C. (Los Alamos, NM); Stotlar, Suzanne C. (Los Alamos, NM)

    1986-01-01T23:59:59.000Z

    The disclosure is directed to an apparatus for detecting radiation having wavelengths from about 0.4 .mu.m to about 5.6 .mu.m. An optical coating is applied to a thermal sensor that is normally transparent to radiation with such wavelengths. The optical coating is thin and light and includes a modifier and an absorber. The thermal sensor can be a pyroelectric detector such as strontium barium niobate.

  11. Emissive sensors and devices incorporating these sensors

    DOE Patents [OSTI]

    Swager, Timothy M; Zhang, Shi-Wei

    2013-02-05T23:59:59.000Z

    The present invention generally relates to luminescent and/or optically absorbing compositions and/or precursors to those compositions, including solid films incorporating these compositions/precursors, exhibiting increased luminescent lifetimes, quantum yields, enhanced stabilities and/or amplified emissions. The present invention also relates to sensors and methods for sensing analytes through luminescent and/or optically absorbing properties of these compositions and/or precursors. Examples of analytes detectable by the invention include electrophiles, alkylating agents, thionyl halides, and phosphate ester groups including phosphoryl halides, cyanides and thioates such as those found in certain chemical warfare agents. The present invention additionally relates to devices and methods for amplifying emissions, such as those produced using the above-described compositions and/or precursors, by incorporating the composition and/or precursor within a polymer having an energy migration pathway. In some cases, the compositions and/or precursors thereof include a compound capable of undergoing a cyclization reaction.

  12. "Towards Optics-Based Measurements in Ocean Observatories"

    E-Print Network [OSTI]

    Boss, Emmanuel S.

    /JPSS ­ UAV ­ Ocean optics, Biological ­ Laser penetration New opportunity · Insitu Sensors ­ (Gliders"Towards Optics-Based Measurements in Ocean Observatories" "Ocean Observatories Contributions to Ocean Models and Data Assimilation For Ecosystems" Ocean Optics 2012 Glasgow Scotland Robert Arnone

  13. Silica–silica Polyimide Buffered Optical Fibre Irradiation and Strength Experiment at Cryogenic Temperatures for 355 nm Pulsed Lasers

    E-Print Network [OSTI]

    Takala, E; Bordini, B; Bottura, L; Bremer, J; Rossi, L

    2012-01-01T23:59:59.000Z

    A controlled UV-light delivery system is envisioned to be built in order to study the stability properties of superconducting strands. The application requires a wave guide from room temperature to cryogenic temperatures. Hydrogen loaded and unloaded polyimide buffered silica–silica 100 microm core fibres were tested at cryogenic temperatures. A thermal stress test was done at 1.9 K and at 4.2 K which shows that the minimal mechanical bending radius for the fibre can be 10 mm for testing (transmission was not measured). The cryogenic transmission loss was measured for one fibre to assess the magnitude of the transmission decrease due to microbending that takes place during cooldown. UV-irradiation degradation measurements were done for bent fibres at 4.2 K with a deuterium lamp and 355 nm pulsed lasers. The irradiation tests show that the fibres have transmission degradation only for wavelengths smaller than 330 nm due to the two photon absorption. The test demonstrates that the fibres are suitable for the ...

  14. Observation of room temperature optical absorption in InP/GaAs type-II ultrathin quantum wells and quantum dots

    SciTech Connect (OSTI)

    Singh, S. D., E-mail: devsh@rrcat.gov.in; Porwal, S.; Mondal, Puspen; Srivastava, A. K.; Mukherjee, C.; Dixit, V. K.; Sharma, T. K.; Oak, S. M. [Raja Ramanna Centre for Advanced Technology, Indore-452013, Madhya Pradesh (India)

    2014-06-14T23:59:59.000Z

    Room temperature optical absorption process is observed in ultrathin quantum wells (QWs) and quantum dots (QDs) of InP/GaAs type-II band alignment system using surface photovoltage spectroscopy technique, where no measurable photoluminescence signal is available. Clear signature of absorption edge in the sub band gap region of GaAs barrier layer is observed for the ultrathin QWs and QDs, which red shifts with the amount of deposited InP material. Movement of photogenerated holes towards the sample surface is proposed to be the main mechanism for the generation of surface photovoltage in type-II ultrathin QWs and QDs. QDs of smaller size are found to be free from the dislocations as confirmed by the high resolution transmission electron microscopy images.

  15. Fiber optic sensing technology for measuring in-cylinder pressure in automotive engines 

    E-Print Network [OSTI]

    Bae, Taehan

    2006-10-30T23:59:59.000Z

    . Field tests were carried out in a 3-cylinder automotive engine with a piezoelectric pressure sensor as a reference transducer up to about 3500 rpm. The fiber optic sensor data generally matched those measured by the piezoelectric reference sensor...

  16. Harsh Environment Silicon Carbide Sensor Technology for Geothermal Instrumentation

    Broader source: Energy.gov [DOE]

    Project objectives: Develop advanced sensor technology for the direct monitoring of geothermal reservoirs. Engineer sensors to survive and operate in H2O pressures up to 220 bar and temperatures as high as 374o C.

  17. Universal signal processing method for multimode reflective sensors 

    E-Print Network [OSTI]

    Larson, Robert Eugene

    1988-01-01T23:59:59.000Z

    sensitivity, but the sensor configuration is complicated and requires the use of expensive lasers and single mode fibers. Amplitude modulation trades sensitivity for low cost and ease of configuration by using light emitting diodes and multimode fibers. A... fiber optic based sensor using amplitude modulation would provide a simple, low cost solution to the interference problem inherent in the use of composite materials. CHAPTER II BACKGROUND Development of optical fiber sensors started around 1977 [1...

  18. Development of All-Solid-State Sensors for Measurement of Nitric Oxide and Ammonia Concentrations by Optical Absorption in Particle-Laden Combusion Exhaust Streams

    SciTech Connect (OSTI)

    Jerald A. Caton; Kalyan Annamalai

    2003-09-24T23:59:59.000Z

    An all-solid-state continuous-wave (cw) laser system for ultraviolet absorption measurements of the nitric oxide (NO) molecule has been developed and demonstrated. For the NO sensor, 250 nW of tunable cw ultraviolet radiation is produced by sum-frequency-mixing of 532-nm radiation from a diode-pumped Nd:YAG laser and tunable 395-nm radiation from an external cavity diode laser (ECDL). The sum-frequency-mixing process occurs in a beta-barium borate crystal. The nitric oxide absorption measurements are performed by tuning the ECDL and scanning the sum-frequency-mixed radiation over strong nitric oxide absorption lines near 226 nm. The nitric oxide sensor has been used for measurements in the exhaust of a coal-fired laboratory combustion facility. The Texas A&M University boiler burner facility is a 30 kW (100,000 Btu/hr) downward-fired furnace with a steel shell encasing ceramic insulation. Measurements of nitric oxide concentration in the exhaust stream were performed after modification of the facility for laser based NOx diagnostics. The diode-laser-based sensor measurements showed good agreement with the results from physical probe sampling of the combustion exhaust. The diode-laser-based ultraviolet absorption measurements were successful even when the beam was severely attenuated by particulate in the exhaust stream and window fouling. Single-laser-sweep measurements were demonstrated with an effective time resolution of 100 msec, limited at this time by the scan rate of our mechanically tuned ECDL system. Future planned modifications will lead to even faster response times at sensitivity levels at or below 1 ppm.

  19. Sensitive And Selective Chemical Sensor With Nanostructured Surfaces.

    DOE Patents [OSTI]

    Pipino, Andrew C. R. (Gaithersburg, MD)

    2003-02-04T23:59:59.000Z

    A chemical sensor is provided which includes an optical resonator including a nanostructured surface comprising a plurality of nanoparticles bound to one or more surfaces of the resonator. The nanoparticles provide optical absorption and the sensor further comprises a detector for detecting the optical absorption of the nanoparticles or their environment. In particular, a selective chemical interaction is provided which modifies the optical absorption of the nanoparticles or their environment, and an analyte is detected based on the modified optical absorption. A light pulse is generated which enters the resonator to interrogate the modified optical absorption and the exiting light pulse is detected by the detector.

  20. Effect of electrolytes and temperature on dications and radical cations of carotenoids: Electrochemical, optical absorption, and high-performance liquid chromatography studies

    SciTech Connect (OSTI)

    He, Z.; Kispert, L.D.

    1999-11-25T23:59:59.000Z

    The effect of supporting electrolytes and temperature on the behavior of dications and radical cations of carotenoids is studied. Cyclic voltammograms (CVs) of canthaxanthin (I) at 23 and {minus}25 C show that Car{sup sm{underscore}bullet+} of I has similar stability during the time of the CV scan, when using tetrabutylammonium perchlorate (TBAPC), tetrabutylammonium tetrafluoroborate (TBATFB), or tetrabutylammonium hexafluorophosphate (TBAHFP) as supporting electrolyte. However, the stability of Car{sup 2+} decreases when using TBAPC or TBATFB; {beta}-carotene (II) shows similar behavior. The CV of I at {minus}25 C shows a strong cathodic wave (wave 6) near {minus}0.15 V (vs Ag) with an intensity about half that of the neutral oxidation wave when TBAPC or TBATFB is the supporting electrolyte. When TBAHFP is used, wave 6 (ca. {minus}0.05 V vs Ag) is ca. 8 times weaker than when TBAPC or TBATFB is used. This wave results from the reduction of a species that may be a decay product of Car{sup 2+} of I. Results show that these electrolytes commonly used in electrochemical studies may affect the studied systems to different extents. In simultaneous bulk electrolysis (BE) and optical absorption spectroscopic measurements, the absorption band of Car{sup 2+} of I in the presence of 0.1 M TBAHFP can be observed by lowering the BE temperature to {minus}20 C. In the presence of 0.1 M TBAPC or TBATFB, this band is not observed, even at {minus}50 C. Isomerization of neutral I (as shown by HPLC and its blue absorption band shift) is observed only when the Car{sup 2+} absorption band is absent during BE. This observation, along with an increase of the neutral absorption band after stopping BE, suggests that the equilibrium Car + Car{sup 2+} {r{underscore}equilibrium} 2Car{sup {sm{underscore}bullet}+} is shifted to the left because Car{sup 2+} decays more quickly than Car{sup {sm{underscore}bullet}+} in the presence of electrolyte and this is a major path for formation of cis neutral species from cis Car{sup {sm{underscore}bullet}+}. The optical absorption of Car{sup 2+} of I at 18 C in the presence of 0.1 M TBAHFP is obtained, which suggests that Car{sup 2+} of I is not as unstable at room temperature in the presence of TBAHFP as was thought before.

  1. A DSP embedded optical naviagtion system

    E-Print Network [OSTI]

    Gunnam, Kiran Kumar

    2004-09-30T23:59:59.000Z

    of alternative technologies. One such technology is the vision-based navigation (VISNAV) sensor system developed at Texas A&M University. VISNAV comprises an electro-optical sensor combined with light sources or beacons. This patented sensor has an analog...

  2. A DSP embedded optical naviagtion system 

    E-Print Network [OSTI]

    Gunnam, Kiran Kumar

    2004-09-30T23:59:59.000Z

    of alternative technologies. One such technology is the vision-based navigation (VISNAV) sensor system developed at Texas A&M University. VISNAV comprises an electro-optical sensor combined with light sources or beacons. This patented sensor has an analog...

  3. RFID tag antenna based temperature sensing

    E-Print Network [OSTI]

    Bhattacharyya, Rahul

    Temperature monitoring is important in a number of fields, particularly cold supply chain applications. Most commercial wireless temperature sensors consist of transceivers, memory and batteries to maintain a temperature ...

  4. Annealing temperature and barrier thickness effect on the structural and optical properties of silicon nanocrystals/SiO{sub 2} superlattices

    SciTech Connect (OSTI)

    López-Vidrier, J., E-mail: jlopezv@el.ub.edu; Hernández, S.; López-Conesa, L.; Peiró, F.; Garrido, B. [MIND–IN2UB, Electronics Department, University of Barcelona, Martí i Franquès 1, E–08028 Barcelona (Spain); Hiller, D.; Gutsch, S.; Zacharias, M. [IMTEK, Faculty of Engineering, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 103, D-79110 Freiburg (Germany); Estradé, S. [MIND–IN2UB, Electronics Department, University of Barcelona, Martí i Franquès 1, E–08028 Barcelona (Spain); TEM–MAT, CCiT–UB, Scientific and Technological Center - University of Barcelona, Solé i Sabarís 1, E–08028 Barcelona (Spain)

    2014-10-07T23:59:59.000Z

    The effect of the annealing temperature and the SiO{sub 2} barrier thickness of silicon nanocrystal (NC)/SiO{sub 2} superlattices (SLs) on their structural and optical properties is investigated. Energy-filtered transmission electron microscopy (TEM) revealed that the SL structure is maintained for annealing temperatures up to 1150?°C, with no variation on the nanostructure morphology for different SiO{sub 2} barrier thicknesses. Nevertheless, annealing temperatures as high as 1250?°C promote diffusion of Si atoms into the SiO{sub 2} barrier layers, which produces larger Si NCs and the loss of the NC size control expected from the SL approach. Complementary Raman scattering measurements corroborated these results for all the SiO{sub 2} and Si-rich oxynitride layer thicknesses. In addition, we observed an increasing crystalline fraction up to 1250?°C, which is related to a decreasing contribution of the suboxide transition layer between Si NCs and the SiO{sub 2} matrix due to the formation of larger NCs. Finally, photoluminescence measurements revealed that the emission of the superlattices exhibits a Gaussian-like lineshape with a maximum intensity after annealing at 1150?°C, indicating a high crystalline degree in good agreement with Raman results. Samples submitted to higher annealing temperatures display a progressive emission broadening, together with an increase in the central emission wavelength. Both effects are related to a progressive broadening of the size distribution with a larger mean size, in agreement with TEM observations. On the other hand, whereas the morphology of the Si NCs is unaffected by the SiO{sub 2} barrier thickness, the emission properties are slightly modified. These observed modifications in the emission lineshape allow monitoring the precipitation process of Si NCs in a direct non-destructive way. All these experimental results evidence that an annealing temperature of 1150?°C and 1-nm SiO{sub 2} barrier can be reached whilst preserving the SL structure, being thus the optimal structural SL parameters for their use in optoelectronics.

  5. Effect of temperature on the optical and structural properties of hexadecylamine capped ZnS nanoparticles using Zinc(II) N-ethyl-N-phenyldithiocarbamate as single source precursor

    SciTech Connect (OSTI)

    Onwudiwe, Damian C., E-mail: dconwudiwe@webmail.co.za [Chemical Resource Beneficiation, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Strydom, Christien [Chemical Resource Beneficiation, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa)] [Chemical Resource Beneficiation, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Oluwafemi, Oluwatobi S., E-mail: oluwafemi.oluwatobi@gmail.com [Department of Chemistry and Chemical Technology, Walter Sisulu University, Mthatha Campus, Private Bag X1, Mthatha (South Africa); Songca, Sandile P. [Faculty of Science, Engineering and Technology, Walter Sisulu University, P.O. Box 19712, Tecoma, East London (South Africa)] [Faculty of Science, Engineering and Technology, Walter Sisulu University, P.O. Box 19712, Tecoma, East London (South Africa)

    2012-12-15T23:59:59.000Z

    Graphical abstract: Display Omitted Highlights: ? HDA-capped ZnS nanoparticles were synthesized via thermolysis of a single source precursor. ? Zinc(II) N-ethyl-N-phenyldithiocarbamate was used as the single source precursor. ? The growth temperature was varied to study the optical properties of the nanocrystals. ? Change in growth temperature affects the structural properties of the ZnS nanoparticles. ? Hexagonal wurtzite phase was obtained at lower temperatures while cubic sphalerite phase was obtained at higher growth temperatures. -- Abstract: Reported in this work is the synthesis of HDA (hexadecylamine)-capped ZnS nanoparticles by a single source route using Zinc(II) N-ethyl-N-phenyldithiocarbamate as a precursor. By varying the growth temperature, the temporal evolution of the optical properties and morphology of the nanocrystals were investigated. The as-synthesized nanoparticles were characterized using UV–vis absorption and photoluminescence (PL) spectroscopy, transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). All the particles exhibited quantum confinement in their optical properties with band edge emission at the early stage of the reaction. The XRD showed transition from hexagonal wurtzite phase to cubic sphalerite phase as the growth temperature increases. The TEM image showed that the particles are small and spherical in shape while the HRTEM image confirmed the crystalline nature of the material.

  6. Probing channel temperature profiles in Al{sub x}Ga{sub 1?x}N/GaN high electron mobility transistors on 200?mm diameter Si(111) by optical spectroscopy

    SciTech Connect (OSTI)

    Kyaw, L. M., E-mail: a0048661@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore); Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology, and Research), Singapore 117602 (Singapore); Bera, L. K.; Dolmanan, S. B.; Tan, H. R.; Bhat, T. N.; Tripathy, S., E-mail: tripathy-sudhiranjan@imre.a-star.edu.sg [Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology, and Research), Singapore 117602 (Singapore); Liu, Y.; Bera, M. K.; Singh, S. P.; Chor, E. F. [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore)

    2014-08-18T23:59:59.000Z

    Using micro-Raman and photoluminescence (PL) techniques, the channel temperature profile is probed in Al{sub x}Ga{sub 1-x}N/GaN high electron mobility transistors (HEMTs) fabricated on a 200?mm diameter Si(111) substrate. In particular, RuO{sub x}-based gate is used due to the semitransparent nature to the optical excitation wavelengths, thus allowing much accurate thermal investigations underneath the gate. To determine the channel temperature profile in devices subjected to different electrical bias voltages, the GaN band-edge PL peak shift calibration with respect to temperature is used. PL analyses show a maximum channel temperature up to 435?K underneath the gate edge between gate and drain, where the estimated thermal resistance in such a HEMT structure is about 13.7 KmmW{sup ?1} at a power dissipation of ?10?W/mm. The temperature profiles from micro-Raman measurements are also addressed from the E{sub 2}-high optical phonon peak shift of GaN, and this method also probes the temperature-induced peak shifts of optical phonon from Si thus showing the nature of thermal characteristics at the AlN/Si substrate interface.

  7. Sensor Relocation with Mobile Sensors:Sensor Relocation with Mobile Sensors: Design,Design,

    E-Print Network [OSTI]

    Schindelhauer, Christian

    Sensor Relocation with Mobile Sensors:Sensor Relocation with Mobile Sensors: Design,Design, Implementation, and EvaluationImplementation, and Evaluation Jie Teng, Tim Bolbrock, Guohong Cao, and Tom La of Freiburg #12;OverviewOverview · Sensor networks · mobile sensor · mobile robot · Mote · sensor relocation

  8. Optical microphone

    DOE Patents [OSTI]

    Veligdan, James T. (Manorville, NY)

    2000-01-11T23:59:59.000Z

    An optical microphone includes a laser and beam splitter cooperating therewith for splitting a laser beam into a reference beam and a signal beam. A reflecting sensor receives the signal beam and reflects it in a plurality of reflections through sound pressure waves. A photodetector receives both the reference beam and reflected signal beam for heterodyning thereof to produce an acoustic signal for the sound waves. The sound waves vary the local refractive index in the path of the signal beam which experiences a Doppler frequency shift directly analogous with the sound waves.

  9. Temperature-sensitive optrode

    DOE Patents [OSTI]

    Hirschfeld, T.B.

    1985-09-24T23:59:59.000Z

    Method and apparatus are provided for measuring temperature and for generating optical signals related to temperature. Light from a fiber optic is directed to a material whose fluorescent response varies with ambient temperature. The same fiber optic delivering the excitation beam also collects a portion of the fluorescent emission for analysis. Signal collection efficiency of the fiber optic is enhanced by requiring that the fluorescent probe material be in the shape of an oblong parabolically tapered solid. Reproducibility is enhanced by using Raman backscatter to monitor excitation beam fluctuations, and by using measurements of fluorescence lifetime. 10 figs.

  10. Micromachined pressure sensors: Review and recent developments

    SciTech Connect (OSTI)

    Eaton, W.P.; Smith, J.H. [Sandia National Labs., Albuquerque, NM (United States). Intelligent Micromachines Dept.

    1997-03-01T23:59:59.000Z

    Since the discovery of piezoresistivity in silicon in the mid 1950s, silicon-based pressure sensors have been widely produced. Micromachining technology has greatly benefited from the success of the integrated circuits industry, burrowing materials, processes, and toolsets. Because of this, microelectromechanical systems (MEMS) are now poised to capture large segments of existing sensor markets and to catalyze the development of new markets. Given the emerging importance of MEMS, it is instructive to review the history of micromachined pressure sensors, and to examine new developments in the field. Pressure sensors will be the focus of this paper, starting from metal diaphragm sensors with bonded silicon strain gauges, and moving to present developments of surface-micromachined, optical, resonant, and smart pressure sensors. Considerations for diaphragm design will be discussed in detail, as well as additional considerations for capacitive and piezoresistive devices.

  11. Dissolved oxygen and pH monitoring within cell culture media using a hydrogel microarray sensor 

    E-Print Network [OSTI]

    Lee, Seung Joon

    2009-05-15T23:59:59.000Z

    based on the fluorescence image of the sensor. The system included a blue LED as an illumination source, coupling optics, interference filters and a compact moisture resistant CCD camera. Various tests were performed for the sensor (sensitivity...

  12. SEA SURFACE CURRENT FIELDS IN THE BALTIC SEA DERIVED FROM MULTI-SENSOR SATELLITE DATA

    E-Print Network [OSTI]

    Hamburg,.Universität

    -sensor, algae blooms, surface currents, optical flow ABSTRACT: Mesoscale dynamic sea surface features demonstrate the use of multi- sensor / multi-channel satellite images for the computation of mesoscale surface

  13. Development of Tools for Measuring Temperature, Flow, Pressure...

    Broader source: Energy.gov (indexed) [DOE]

    3 4.4.3 Development of Tools for Measuring Temperature, Flow, Pressure, and Seismicity of EGS Reservoirs - 300 C Capable Electronics Platform and Temperature Sensor System for...

  14. Distributed Temperature Sensing: Review of Technology and Applications

    E-Print Network [OSTI]

    Ukil, A; Krippner, P

    2015-01-01T23:59:59.000Z

    Distributed temperature sensors (DTS) measure temperatures by means of optical fibers. Those optoelectronic devices provide a continuous profile of the temperature distribution along the cable. Initiated in the 1980s, DTS systems have undergone significant improvements in the technology and the application scenario over the last decades. The main measuring principles are based on detecting the back-scattering of light, e.g., detecting via Rayleigh, Raman, Brillouin principles. The application domains span from traditional applications in the distributed temperature or strain sensing in the cables, to the latest smart grid initiative in the power systems, etc. In this paper, we present comparative reviews of the different DTS technologies, different applications, standard and upcoming, different manufacturers.

  15. A fiber optic probe for oxygen partial pressure sensing 

    E-Print Network [OSTI]

    Schlain, Leslie Ariel

    1986-01-01T23:59:59.000Z

    of the electronic circuitry, and Steve Spar for software development. TABLE OF CONTENTS INTRODUCTION Purpose Current Status of Conventional Oxygen Sensors Optical Sensors Technical Obj ect ives 1 5 10 MATERIAL AND METHODS 14 Transducer Design... the partial pressure of oxygen (p02) in solutions. The research effort was specifically aimed at the development of an oxygen sensor suitable for physiological applications. The sensor described in this thesis is an application of a generic fiber optic...

  16. Development of All-Solid-State Sensors for Measurement of Nitric Oxide and Ammonia Concentrations by Optical Absorption in Particle-Laden Combustion Exhaust Streams

    SciTech Connect (OSTI)

    Jerald A. Caton; Kalyan Annamalai; Robert P. Lucht

    2006-12-31T23:59:59.000Z

    An all-solid-state continuous-wave (cw) laser system for ultraviolet absorption measurements of the nitric oxide (NO) molecule has been developed and demonstrated. For the NO sensor, 250 nW of tunable cw ultraviolet radiation is produced by sum-frequency-mixing of 532-nm radiation from a diode-pumped Nd:YAG laser and tunable 395-nm radiation from an external cavity diode laser (ECDL). The sum-frequency-mixing process occurs in a beta-barium borate crystal. The nitric oxide absorption measurements are performed by tuning the ECDL and scanning the sum-frequency-mixed radiation over strong nitric oxide absorption lines near 226 nm. In Year 1 of the research, the nitric oxide sensor was used for measurements in the exhaust of a coal-fired laboratory combustion facility. The Texas A&M University boiler burner facility is a 30 kW (100,000 Btu/hr) downward-fired furnace with a steel shell encasing ceramic insulation. Measurements of nitric oxide concentration in the exhaust stream were performed after modification of the facility for laser based NOx diagnostics. The diode-laser-based ultraviolet absorption measurements were successful even when the beam was severely attenuated by particulate in the exhaust stream and window fouling. Single-laser-sweep measurements were demonstrated with an effective time resolution of 100 msec, limited at this time by the scan rate of our mechanically tuned ECDL system. In Year 2, the Toptica ECDL in the original system was replaced with a Sacher Lasers ECDL. The mode-hop-free tuning range and tuning rate of the Toptica ECDL were 25 GHz and a few Hz, respectively. The mode-hop-free tuning range and tuning rate of the Sacher Lasers ECDL were 90 GHz and a few hundred Hz, respectively. The Sacher Lasers ECDL thus allows us to scan over the entire NO absorption line and to determine the absorption baseline with increased accuracy and precision. The increased tuning rate is an advantage in that data can be acquired much more rapidly and the absorption measurements are less susceptible to the effects of transient fluctuations in the properties of the coal combustor exhaust stream. Gas cell measurements were performed using the NO sensor with the new ECDL, and a few spectra were acquired from the coal exhaust stream. However, the laser diode in the new ECDL failed during the coal combustor tests. In Year 3, however, we obtained a new GaN laser diode for our ECDL system, installed it, and completed an extensive series of measurements in the Texas A&M coal-fired laboratory combustion facility. The combustor was operated with coal and coal/biomass as fuels, with and without reburn, and with and without ammonia injection. Several different fuel equivalence ratios were investigated for each operating condition.

  17. Development of All-Solid-State Sensors for Measurement of Nitric Oxide and Ammonia Concentrations by Optical Absorption in Particle-Laden Combustion Exhaust Streams

    SciTech Connect (OSTI)

    Jerald A. Caton; Kalyan Annamalai; Robert P. Lucht

    2005-09-30T23:59:59.000Z

    An all-solid-state continuous-wave (cw) laser system for ultraviolet absorption measurements of the nitric oxide (NO) molecule has been developed and demonstrated. For the NO sensor, 250 nW of tunable cw ultraviolet radiation is produced by sum-frequency-mixing of 532-nm radiation from a diode-pumped Nd:YAG laser and tunable 395-nm radiation from an external cavity diode laser (ECDL). The sum-frequency-mixing process occurs in a beta-barium borate crystal. The nitric oxide absorption measurements are performed by tuning the ECDL and scanning the sum-frequency-mixed radiation over strong nitric oxide absorption lines near 226 nm. In Year 1 of the research, the nitric oxide sensor was used for measurements in the exhaust of a coal-fired laboratory combustion facility. The Texas A&M University boiler burner facility is a 30 kW (100,000 Btu/hr) downward-fired furnace with a steel shell encasing ceramic insulation. Measurements of nitric oxide concentration in the exhaust stream were performed after modification of the facility for laser based NOx diagnostics. The diode-laser-based ultraviolet absorption measurements were successful even when the beam was severely attenuated by particulate in the exhaust stream and window fouling. Single-laser-sweep measurements were demonstrated with an effective time resolution of 100 msec, limited at this time by the scan rate of our mechanically tuned ECDL system. In Year 2, the Toptica ECDL in the original system was replaced with a Sacher Lasers ECDL. The mode-hop-free tuning range and tuning rate of the Toptica ECDL were 25 GHz and a few Hz, respectively. The mode-hop-free tuning range and tuning rate of the Sacher Lasers ECDL were 90 GHz and a few hundred Hz, respectively. The Sacher Lasers ECDL thus allows us to scan over the entire NO absorption line and to determine the absorption baseline with increased accuracy and precision. The increased tuning rate is an advantage in that data can be acquired much more rapidly and the absorption measurements are less susceptible to the effects of transient fluctuations in the properties of the coal combustor exhaust stream. Gas cell measurements were performed using the NO sensor with the new ECDL, and a few spectra were acquired from the coal exhaust stream. However, the laser diode in the new ECDL failed during the coal combustor tests. In Year 3, however, we obtained a new GaN laser diode for our ECDL system, installed it, and completed an extensive series of measurements in the Texas A&M coal-fired laboratory combustion facility. The combustor was operated with coal and coal/biomass as fuels, with and without reburn, and with and without ammonia injection. Several different fuel equivalence ratios were investigated for each operating condition. A series of spectral simulations was performed using the HITRAN code to investigate the potential sensitivity of absorption measurements of ammonia in different spectral regions. It was concluded that ammonia absorption features in the 3000-nm spectral region would be hard to measure due to water vapor interferences. We will concentrate on the spectral region near 1530 nm, where other researchers have had some success in measuring ammonia.

  18. DEVELOPMENT OF ALL-SOLID-STATE SENSORS FOR MEASUREMENT OF NITRIC OXIDE AND AMMONIA CONCENTRATIONS BY OPTICAL ABSORPTION IN PARTICLE-LADEN COMBUSTION EXHAUST STREAMS

    SciTech Connect (OSTI)

    Jerald A. Caton; Kalyan Annamalai; Robert P. Lucht

    2004-09-30T23:59:59.000Z

    An all-solid-state continuous-wave (cw) laser system for ultraviolet absorption measurements of the nitric oxide (NO) molecule has been developed and demonstrated. For the NO sensor, 250 nW of tunable cw ultraviolet radiation is produced by sum-frequency-mixing of 532-nm radiation from a diode-pumped Nd:YAG laser and tunable 395-nm radiation from an external cavity diode laser (ECDL). The sum-frequency-mixing process occurs in a beta-barium borate crystal. The nitric oxide absorption measurements are performed by tuning the ECDL and scanning the sum-frequency-mixed radiation over strong nitric oxide absorption lines near 226 nm. In Year 1 of the research, the nitric oxide sensor was used for measurements in the exhaust of a coal-fired laboratory combustion facility. The Texas A&M University boiler burner facility is a 30 kW (100,000 Btu/hr) downward-fired furnace with a steel shell encasing ceramic insulation. Measurements of nitric oxide concentration in the exhaust stream were performed after modification of the facility for laser based NOx diagnostics. The diode-laser-based ultraviolet absorption measurements were successful even when the beam was severely attenuated by particulate in the exhaust stream and window fouling. Single-laser-sweep measurements were demonstrated with an effective time resolution of 100 msec, limited at this time by the scan rate of our mechanically tuned ECDL system. In Year 2 described in this progress report, the Toptica ECDL in the original system was replaced with a Sacher Lasers ECDL. The mode-hop-free tuning range and tuning rate of the Toptica ECDL were 25 GHz and a few Hz, respectively. The mode-hop-free tuning range and tuning rate of the Sacher Lasers ECDL were 90 GHz and a few hundred Hz, respectively. The Sacher Lasers ECDL thus allows us to scan over the entire NO absorption line and to determine the absorption baseline with increased accuracy and precision. The increased tuning rate is an advantage in that data can be acquired much more rapidly and the absorption measurements are less susceptible to the effects of transient fluctuations in the properties of the coal combustor exhaust stream. Gas cell measurements were performed using the NO sensor with the new ECDL, and a few spectra were acquired from the coal exhaust stream. However, the laser diode in the new ECDL failed during the coal combustor tests. A series of spectral simulations was performed using the HITRAN code to investigate the potential sensitivity of absorption measurements of ammonia in different spectral regions. It was concluded that ammonia absorption features in the 3000-nm spectral region would be hard to measure due to water vapor interferences.

  19. Sensor Development for PEM Fuel Cell Systems

    SciTech Connect (OSTI)

    Steve Magee; Richard Gehman

    2005-07-12T23:59:59.000Z

    This document reports on the work done by Honeywell Sensing and Control to investigate the feasibility of modifying low cost Commercial Sensors for use inside a PEM Fuel Cell environment. Both stationary and automotive systems were considered. The target environment is hotter (100 C) than the typical commercial sensor maximum of 70 C. It is also far more humid (100% RH condensing) than the more typical 95% RH non-condensing at 40 C (4% RH maximum at 100 C). The work focused on four types of sensors, Temperature, Pressure, Air Flow and Relative Humidity. Initial design goals were established using a market research technique called Market Driven Product Definition (MDPD). A series of interviews were conducted with various users and system designers in their facilities. The interviewing team was trained in data taking and analysis per the MDPD process. The final result was a prioritized and weighted list of both requirements and desires for each sensor. Work proceeded on concept development for the 4 types of sensors. At the same time, users were developing the actual fuel cell systems and gaining knowledge and experience in the use of sensors and controls systems. This resulted in changes to requirements and desires that were not anticipated during the MDPD process. The concepts developed met all the predicted requirements. At the completion of concept development for the Pressure Sensor, it was determined that the Fuel Cell developers were happy with off-the-shelf automotive pressure sensors. Thus, there was no incentive to bring a new Fuel Cell Specific Pressure Sensor into production. Work was therefore suspended. After the experience with the Pressure Sensor, the requirements for a Temperature Sensor were reviewed and a similar situation applied. Commercially available temperature sensors were adequate and cost effective and so the program was not continued from the Concept into the Design Phase.

  20. Application of Multizone HVAC Control Using Wireless Sensor Networks and Actuating Vent Registers

    E-Print Network [OSTI]

    Watts, W.; Koplow, M.; Redfern, A.; Wright, P.

    2007-01-01T23:59:59.000Z

    on an embedded server, and temperature sensors that were distributed throughout the house. The residence is divided into four Control Zones. Zone 1 contains the downstairs living, dining, and kitchen area. Zone 2 contains the bathrooms and laundry... radiation. The temperature and humidity sensors are manufactured by Sensirion, models SH11 and SH15. The light sensors consist of a thermally sensitive radiation sensor (TSR) and a photosynthetic active radiation sensor, manufactured by Hamamatsu...