National Library of Energy BETA

Sample records for near-field scanning optical

  1. Observation of nonlinear bands in near-field scanning optical microscopy of a photonic-crystal waveguide

    SciTech Connect (OSTI)

    Singh, A.; Huisman, S. R.; Ctistis, G. Mosk, A. P.; Pinkse, P. W. H.; Korterik, J. P.; Herek, J. L.

    2015-01-21

    We have measured the photonic bandstructure of GaAs photonic-crystal waveguides with high resolution in energy as well as in momentum using near-field scanning optical microscopy. Intriguingly, we observe additional bands that are not predicted by eigenmode solvers, as was recently demonstrated by Huisman et al. [Phys. Rev. B 86, 155154 (2012)]. We study the presence of these additional bands by performing measurements of these bands while varying the incident light power, revealing a non-linear power dependence. Here, we demonstrate experimentally and theoretically that the observed additional bands are caused by a waveguide-specific near-field tip effect not previously reported, which can significantly phase-modulate the detected field.

  2. Remote optical sensing on the nanometer scale with a bowtie aperture nano-antenna on a fiber tip of scanning near-field optical microscopy

    SciTech Connect (OSTI)

    Atie, Elie M.; Xie, Zhihua; El Eter, Ali; Salut, Roland; Baida, Fadi I.; Grosjean, Thierry; Nedeljkovic, Dusan; Tannous, Tony

    2015-04-13

    Plasmonic nano-antennas have proven the outstanding ability of sensing chemical and physical processes down to the nanometer scale. Sensing is usually achieved within the highly confined optical fields generated resonantly by the nano-antennas, i.e., in contact to the nanostructures. In this paper, we demonstrate the sensing capability of nano-antennas to their larger scale environment, well beyond their plasmonic confinement volume, leading to the concept of “remote” (non contact) sensing on the nanometer scale. On the basis of a bowtie-aperture nano-antenna (BNA) integrated at the apex of a SNOM (Scanning Near-field Optical Microscopy) fiber tip, we introduce an ultra-compact, moveable, and background-free optical nanosensor for the remote sensing of a silicon surface (up to distance of 300 nm). Sensitivity of the BNA to its large scale environment is high enough to expect the monitoring and control of the spacing between the nano-antenna and a silicon surface with sub-nanometer accuracy. This work paves the way towards an alternative class of nanopositioning techniques, based on the monitoring of diffraction-free plasmon resonance, that are alternative to nanomechanical and diffraction-limited optical interference-based devices.

  3. Scanning tip microwave near field microscope

    DOE Patents [OSTI]

    Xiang, Xiao-Dong; Schultz, Peter G.; Wei, Tao

    1998-01-01

    A microwave near field microscope has a novel microwave probe structure wherein the probing field of evanescent radiation is emitted from a sharpened metal tip instead of an aperture or gap. This sharpened tip, which is electrically and mechanically connected to a central electrode, extends through and beyond an aperture in an endwall of a microwave resonating device such as a microwave cavity resonator or a microwave stripline resonator. Since the field intensity at the tip increases as the tip sharpens, the total energy which is radiated from the tip and absorbed by the sample increases as the tip sharpens. The result is improved spatial resolution without sacrificing sensitivity.

  4. Scanning tip microwave near field microscope

    DOE Patents [OSTI]

    Xiang, X.D.; Schultz, P.G.; Wei, T.

    1998-10-13

    A microwave near field microscope has a novel microwave probe structure wherein the probing field of evanescent radiation is emitted from a sharpened metal tip instead of an aperture or gap. This sharpened tip, which is electrically and mechanically connected to a central electrode, extends through and beyond an aperture in an end wall of a microwave resonating device such as a microwave cavity resonator or a microwave stripline resonator. Since the field intensity at the tip increases as the tip sharpens, the total energy which is radiated from the tip and absorbed by the sample increases as the tip sharpens. The result is improved spatial resolution without sacrificing sensitivity. 17 figs.

  5. Near-Field Magneto-Optical Microscope

    SciTech Connect (OSTI)

    Vlasko-Vlasov, Vitalii; Welp, Ulrich; and Crabtree, George W.

    2005-12-06

    A device and method for mapping magnetic fields of a sample at a resolution less than the wavelength of light without altering the magnetic field of the sample is disclosed. A device having a tapered end portion with a magneto-optically active particle positioned at the distal end thereof in communication with a fiber optic for transferring incoming linearly polarized light from a source thereof to the particle and for transferring reflected light from the particle is provided. The fiber optic has a reflective material trapping light within the fiber optic and in communication with a light detector for determining the polarization of light reflected from the particle as a function of the strength and direction of the magnetic field of the sample. Linearly polarized light from the source thereof transferred to the particle positioned proximate the sample is affected by the magnetic field of the sample sensed by the particle such that the difference in polarization of light entering and leaving the particle is due to the magnetic field of the sample. Relative movement between the particle and sample enables mapping.

  6. Near Field Magneto-Optical Microscope

    DOE Patents [OSTI]

    Vlasko-Vlasov, Vitalii K.; Welp, Ulrich; Crabtree, George W.

    2005-12-06

    A device and method for mapping magnetic fields of a sample at a resolution less than the wavelength of light without altering the magnetic field of the sample is disclosed. A device having a tapered end portion with a magneto-optically active particle positioned at the distal end thereof in communication with a fiber optic for transferring incoming linearly polarized light from a source thereof to the particle and for transferring reflected light from the particle is provided. The fiber optic has a reflective material trapping light within the fiber optic and in communication with a light detector for determining the polarization of light reflected from the particle as a function of the strength and direction of the magnetic field of the sample. Linearly polarized light from the source thereof transferred to the particle positioned proximate the sample is affected by the magnetic field of the sample sensed by the particle such that the difference in polarization of light entering and leaving the particle is due to the magnetic field of the sample. Relative movement between the particle and sample enables mapping.

  7. Dynamic near-field optical interaction between oscillating nanomechanical structures

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

    Ahn, Phillip; Chen, Xiang; Zhang, Zhen; Ford, Matthew; Rosenmann, Daniel; Jung, II Woong; Sun, Cheng; Balogun, Oluwaseyi

    2015-05-27

    Near-field optical techniques exploit light-matter interactions at small length scales for mechanical sensing and actuation of nanomechanical structures. Here, we study the optical interaction between two mechanical oscillators—a plasmonic nanofocusing probe-tip supported by a low frequency cantilever, and a high frequency nanomechanical resonator—and leverage their interaction for local detection of mechanical vibrations. The plasmonic nanofocusing probe provides a confined optical source to enhance the interaction between the two oscillators. Dynamic perturbation of the optical cavity between the probe-tip and the resonator leads to nonlinear modulation of the scattered light intensity at the sum and difference of their frequencies. This double-frequencymore » demodulation scheme is explored to suppress unwanted background and to detect mechanical vibrations with a minimum detectable displacement sensitivity of 0.45pm/Hz1/2, which is limited by shot noise and electrical noise. We explore the demodulation scheme for imaging the bending vibration mode shape of the resonator with a lateral spatial resolution of 20nm. We also demonstrate the time-resolved aspect of the local optical interaction by recording the ring-down vibrations of the resonator at frequencies of up to 129MHz. The near-field optical technique is promising for studying dynamic mechanical processes in individual nanostructures.« less

  8. Dynamic near-field optical interaction between oscillating nanomechanical structures

    SciTech Connect (OSTI)

    Ahn, Phillip; Chen, Xiang; Zhang, Zhen; Ford, Matthew; Rosenmann, Daniel; Jung, II Woong; Sun, Cheng; Balogun, Oluwaseyi

    2015-05-27

    Near-field optical techniques exploit light-matter interactions at small length scales for mechanical sensing and actuation of nanomechanical structures. Here, we study the optical interaction between two mechanical oscillators—a plasmonic nanofocusing probe-tip supported by a low frequency cantilever, and a high frequency nanomechanical resonator—and leverage their interaction for local detection of mechanical vibrations. The plasmonic nanofocusing probe provides a confined optical source to enhance the interaction between the two oscillators. Dynamic perturbation of the optical cavity between the probe-tip and the resonator leads to nonlinear modulation of the scattered light intensity at the sum and difference of their frequencies. This double-frequency demodulation scheme is explored to suppress unwanted background and to detect mechanical vibrations with a minimum detectable displacement sensitivity of 0.45pm/Hz1/2, which is limited by shot noise and electrical noise. We explore the demodulation scheme for imaging the bending vibration mode shape of the resonator with a lateral spatial resolution of 20nm. We also demonstrate the time-resolved aspect of the local optical interaction by recording the ring-down vibrations of the resonator at frequencies of up to 129MHz. The near-field optical technique is promising for studying dynamic mechanical processes in individual nanostructures.

  9. Near field optical probe for critical dimension measurements

    DOE Patents [OSTI]

    Stallard, B.R.; Kaushik, S.

    1999-05-18

    A resonant planar optical waveguide probe for measuring critical dimensions on an object in the range of 100 nm and below is disclosed. The optical waveguide includes a central resonant cavity flanked by Bragg reflector layers with input and output means at either end. Light is supplied by a narrow bandwidth laser source. Light resonating in the cavity creates an evanescent electrical field. The object with the structures to be measured is translated past the resonant cavity. The refractive index contrasts presented by the structures perturb the field and cause variations in the intensity of the light in the cavity. The topography of the structures is determined from these variations. 8 figs.

  10. Multipass laser amplification with near-field far-field optical separation

    DOE Patents [OSTI]

    Hagen, Wilhelm F.

    1979-01-01

    This invention discloses two classes of optical configurations for high power laser amplification, one allowing near-field and the other allowing far-field optical separation, for the multiple passage of laser pulses through one or more amplifiers over an open optical path. These configurations may reimage the amplifier or any other part of the cavity on itself so as to suppress laser beam intensity ripples that arise from diffraction and/or non-linear effects. The optical cavities combine the features of multiple passes, spatial filtering and optical reimaging and allow sufficient time for laser gain recovery.

  11. Near field optical scanning system employing microfabricated solid immersion lens

    DOE Patents [OSTI]

    Cozier, Kenneth B.; Fletcher, Daniel A.; Kino, Gordon S.; Quate, Calvin F.; Soh, Hyongsok T.

    2002-08-27

    A solid immersion lens integrated on a flexible support such as a cantilever or membrane is described, together with a method of forming the integrated structure.

  12. Direct measurement of optical force induced by near-field plasmonic cavity using dynamic mode AFM

    SciTech Connect (OSTI)

    Guan, Dongshi; Hang, Zhi Hong; Marset, Zsolt; Liu, Hui; Kravchenko, Ivan I.; Chan, Ho Bun; Chan, C. T.; Tong, Penger

    2015-11-20

    Plasmonic nanostructures have attracted much attention in recent years because of their potential applications in optical manipulation through near-field enhancement. Continuing experimental efforts have been made to develop accurate techniques to directly measure the near-field optical force induced by the plasmonic nanostructures in the visible frequency range. In this work, we report a new application of dynamic mode atomic force microscopy (DM-AFM) in the measurement of the enhanced optical force acting on a nano-structured plasmonic resonant cavity. The plasmonic cavity is made of an upper gold-coated glass sphere and a lower quartz substrate patterned with an array of subwavelength gold disks. In the near-field when the sphere is positioned close to the disk array, plasmonic resonance is excited in the cavity and the induced force by a 1550 nm infrared laser is found to be increased by an order of magnitude compared with the photon pressure generated by the same laser light. Lastly, the experiment demonstrates that DM-AFM is a powerful tool for the study of light induced forces and their enhancement in plasmonic nanostructures.

  13. Direct measurement of optical force induced by near-field plasmonic cavity using dynamic mode AFM

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

    Guan, Dongshi; Hang, Zhi Hong; Marset, Zsolt; Liu, Hui; Kravchenko, Ivan I.; Chan, Ho Bun; Chan, C. T.; Tong, Penger

    2015-11-20

    Plasmonic nanostructures have attracted much attention in recent years because of their potential applications in optical manipulation through near-field enhancement. Continuing experimental efforts have been made to develop accurate techniques to directly measure the near-field optical force induced by the plasmonic nanostructures in the visible frequency range. In this work, we report a new application of dynamic mode atomic force microscopy (DM-AFM) in the measurement of the enhanced optical force acting on a nano-structured plasmonic resonant cavity. The plasmonic cavity is made of an upper gold-coated glass sphere and a lower quartz substrate patterned with an array of subwavelength goldmore » disks. In the near-field when the sphere is positioned close to the disk array, plasmonic resonance is excited in the cavity and the induced force by a 1550 nm infrared laser is found to be increased by an order of magnitude compared with the photon pressure generated by the same laser light. Lastly, the experiment demonstrates that DM-AFM is a powerful tool for the study of light induced forces and their enhancement in plasmonic nanostructures.« less

  14. Conference Paper NFO-7:7th International Conference on Near-Field Optics and Related Technologies

    SciTech Connect (OSTI)

    Prof.Dr. Lukas Novotny

    2004-10-18

    The seventh conference in the NFO conference series, held here in Rochester, provided to be the principal forum for advances in sub-wavelength optics, near-field optical microscopy, local field enhancement, instrumental developments and the ever-increasing range of applications. This conference brought together the diverse scientific communities working on the theory and application of near-field optics (NFO) and related techniques.

  15. Near-Field Magneto-Optical Microscope (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Publication: United States Language: English Subject: 47 OTHER INSTRUMENTATION; FIBER OPTICS; MAGNETIC FIELDS; MICROSCOPES; POLARIZATION; RESOLUTION; DESIGN; OPERATION Word Cloud...

  16. Optical scanning apparatus

    DOE Patents [OSTI]

    Villarreal, R.A.

    1985-11-06

    An optical scanner employed in a radioactive environment for reading indicia imprinted about a cylindrical surface of an article by means of an optical system including metallic reflective and mirror surfaces resistant to degradation and discoloration otherwise imparted to glass surfaces exposed to radiation is described.

  17. Attosecond nanoscale near-field sampling

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

    Forg, B.; Schotz, J.; SuBmann, F.; Forster, M.; Kruger, M.; Ahn, B.; Okell, W. A.; Wintersperger, K.; Zherebtsov, S.; Guggenmos, A.; et al

    2016-05-31

    The promise of ultrafast light-field-driven electronic nanocircuits has stimulated the development of the new research field of attosecond nanophysics. An essential prerequisite for advancing this new area is the ability to characterize optical near fields from light interaction with nanostructures, with sub-cycle resolution. Here we experimentally demonstrate attosecond near-field retrieval for a tapered gold nanowire. Furthermore, by comparison of the results to those obtained from noble gas experiments and trajectory simulations, the spectral response of the nanotaper near field arising from laser excitation can be extracted.

  18. Spectroscopic infrared near-field microscopy and x-ray reflectivity studies of order and clustering in lipid membranes

    SciTech Connect (OSTI)

    Generosi, J.; Margaritondo, G.; Sanghera, J. S.; Aggarwal, I. D.; Tolk, N. H.; Piston, D. W.; Castellano, A. Congiu; Cricenti, A.

    2006-12-04

    Lipid membranes were studied by infrared scanning near-field optical microscopy at several wavelengths and by x-ray reflectivity. Together with the x-ray data, the optical images indicate the formation of locally ordered multiple bilayers, and the topographical micrographs reveal the presence of islands at the surface, both critically important features for biotechnology and medical applications such as biosensors and gene therapy.

  19. Scanning optical microscope with long working distance objective

    DOE Patents [OSTI]

    Cloutier, Sylvain G.

    2010-10-19

    A scanning optical microscope, including: a light source to generate a beam of probe light; collimation optics to substantially collimate the probe beam; a probe-result beamsplitter; a long working-distance, infinity-corrected objective; scanning means to scan a beam spot of the focused probe beam on or within a sample; relay optics; and a detector. The collimation optics are disposed in the probe beam. The probe-result beamsplitter is arranged in the optical paths of the probe beam and the resultant light from the sample. The beamsplitter reflects the probe beam into the objective and transmits resultant light. The long working-distance, infinity-corrected objective is also arranged in the optical paths of the probe beam and the resultant light. It focuses the reflected probe beam onto the sample, and collects and substantially collimates the resultant light. The relay optics are arranged to relay the transmitted resultant light from the beamsplitter to the detector.

  20. Terahertz near-field imaging of surface plasmon waves in graphene structures

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

    Mitrofanov, O.; Yu, W.; Thompson, R. J.; Jiang, Y.; Greenberg, Z. J.; Palmer, J.; Brener, I.; Pan, W.; Berger, C.; de Heer, W. A.; et al

    2015-09-08

    In this study, we introduce a near-field scanning probe terahertz (THz) microscopy technique for probing surface plasmon waves on graphene. Based on THz time-domain spectroscopy method, this near-field imaging approach is well suited for studying the excitation and evolution of THz plasmon waves on graphene as well as for mapping of graphene properties at THz frequencies on the sub-wavelength scale.

  1. SCAN+

    SciTech Connect (OSTI)

    Kenneth Krebs, John Svoboda

    2009-11-01

    SCAN+ is a software application specifically designed to control the positioning of a gamma spectrometer by a two dimensional translation system above spent fuel bundles located in a sealed spent fuel cask. The gamma spectrometer collects gamma spectrum information for the purpose of spent fuel cask fuel loading verification. SCAN+ performs manual and automatic gamma spectrometer positioning functions as-well-as exercising control of the gamma spectrometer data acquisitioning functions. Cask configuration files are used to determine the positions of spent fuel bundles. Cask scanning files are used to determine the desired scan paths for scanning a spent fuel cask allowing for automatic unattended cask scanning that may take several hours.

  2. Near-field/altered-zone models report

    SciTech Connect (OSTI)

    Hardin, E. L., LLNL

    1998-03-01

    lithophysal units. These units are made up of moderately to densely welded, devitrified, fractured tuff. The rock's chemical composition is comparable to that of typical granite, but has textural features and mineralogical characteristics of large-scale, silicic volcanism. Because the repository horizon will be approximately 300 m below the ground surface and 200 m above the water table, the repository will be partially saturated. The welded tuff matrix in the host units is highly impermeable, but water and gas flow readily through fractures. The degree of fracturing in these units is highly variable, and the hydrologic significance of fracturing is an important aspect of site investigation. This report describes the characterization and modeling of a region around the potential repository--the altered zone--a region in which the temperature will be increased significantly by waste-generated heat. Numerical simulation has shown that, depending on the boundary conditions, rock properties, and repository design features incorporated in the models, the altered zone (AZ) may extend from the water table to the ground surface. This report also describes models of the near field, the region comprising the repository emplacement drifts and the surrounding rock, which are critical to the performance of engineered components. Investigations of near-field and altered-zone (NF/AZ) processes support the design of underground repository facilities and engineered barriers and also provide constraint data for probabilistic calculations of waste-isolation performance (i.e., performance assessment). The approach to investigation, which is an iterative process involving hypothesis testing and experimentation, has relied on conceptualizing engineered barriers and on performance analysis. This report is a collection, emphasizing conceptual and numerical models, of the recent results contributed from studies of NF/AZ processes and of quantitative measures of NF/AZ performance. The selection and

  3. SCAN+

    Energy Science and Technology Software Center (OSTI)

    2009-11-01

    SCAN+ is a software application specifically designed to control the positioning of a gamma spectrometer by a two dimensional translation system above spent fuel bundles located in a sealed spent fuel cask. The gamma spectrometer collects gamma spectrum information for the purpose of spent fuel cask fuel loading verification. SCAN+ performs manual and automatic gamma spectrometer positioning functions as-well-as exercising control of the gamma spectrometer data acquisitioning functions. Cask configuration files are used to determinemore » the positions of spent fuel bundles. Cask scanning files are used to determine the desired scan paths for scanning a spent fuel cask allowing for automatic unattended cask scanning that may take several hours.« less

  4. SCAN+

    Energy Science and Technology Software Center (OSTI)

    2009-11-01

    SCAN+ is a software application specifically designed to control the positioning of a gamma spectrometer by a two dimensional translation system above spent fuel bundles located in a sealed spent fuel cask. The gamma spectrometer collects gamma spectrum information for the purpose of spent fuel cask fuel loading verification. SCAN+ performs manual and automatic gamma spectrometer positioning functions as-well-as exercising control of the gamma spectrometer data acquisitioning functions. Cask configuration files are used to determinemorethe positions of spent fuel bundles. Cask scanning files are used to determine the desired scan paths for scanning a spent fuel cask allowing for automatic unattended cask scanning that may take several hours.less

  5. A unidirectional subwavelength focusing near-field plate

    SciTech Connect (OSTI)

    Imani, Mohammadreza F.; Grbic, Anthony

    2014-01-28

    Near-field plates consist of non-periodically patterned surfaces that can overcome the diffraction limit and confine electromagnetic fields to subwavelength dimensions. Previous near-field plates experimentally demonstrated extreme field tailoring capabilities. However, their performance suffered from radiation/reflection in undesired directions, those other than the subwavelength focus. This issue can limit the practical use of near-field plates. In this paper, we address this issue by designing a unidirectional near-field plate that can form a subwavelength focal pattern, while suppressing the field radiated/reflected in other directions. The design and operation of the proposed unidirectional near-field plate are verified through full-wave simulation. The unidirectional near-field plate may find application in high resolution imaging and probing, high density data storage, and wireless power transfer systems. As an example, its utility as a high resolution probe is demonstrated through full-wave electromagnetic simulation.

  6. Optical scanning apparatus for indicia imprinted about a cylindrical axis

    DOE Patents [OSTI]

    Villarreal, Richard A.

    1987-01-01

    An optical scanner employed in a radioactive environment for reading indicia imprinted about a cylindrical surface of an article by means of an optical system including metallic reflective and mirror surfaces resistant to degradation and discoloration otherwise imparted to glass surfaces exposed to radiation.

  7. High-Resolution Photocurrent Microscopy Using Near-FieldCathodolumine...

    Office of Scientific and Technical Information (OSTI)

    High-Resolution Photocurrent Microscopy Using Near-Field Cathodoluminescence of Quantum Dots. Citation Details In-Document Search Title: High-Resolution Photocurrent Microscopy ...

  8. Graphene-assisted near-field radiative heat transfer between corrugated polar materials

    SciTech Connect (OSTI)

    Liu, X. L.; Zhang, Z. M.

    2014-06-23

    Graphene has attracted great attention in nanoelectronics, optics, and energy harvesting. Here, the near-field radiative heat transfer between graphene-covered corrugated silica is investigated based on the exact scattering theory. It is found that graphene can improve the radiative heat flux between silica gratings by more than one order of magnitude and alleviate the performance sensitivity to lateral shift. The underlying mechanism is mainly attributed to the improved photon tunneling of modes away from phonon resonances. Besides, coating with graphene leads to nonlocal radiative transfer that breaks Derjaguin's proximity approximation and enables corrugated silica to outperform bulk silica in near-field radiation.

  9. Resonance hybridization and near field properties of strongly coupled plasmonic ring dimer-rod nanosystem

    SciTech Connect (OSTI)

    Koya, Alemayehu Nana; Ji, Boyu; Hao, Zuoqiang; Lin, Jingquan

    2015-09-21

    Combined effects of polarization, split gap, and rod width on the resonance hybridization and near field properties of strongly coupled gold dimer-rod nanosystem are comparatively investigated in the light of the constituent nanostructures. By aligning polarization of the incident light parallel to the long axis of the nanorod, introducing small split gaps to the dimer walls, and varying width of the nanorod, we have simultaneously achieved resonance mode coupling, huge near field enhancement, and prolonged plasmon lifetime. As a result of strong coupling between the nanostructures and due to an intense confinement of near fields at the split and dimer-rod gaps, the extinction spectrum of the coupled nanosystem shows an increase in intensity and blueshift in wavelength. Consequently, the near field lifespan of the split-nanosystem is prolonged in contrast to the constituent nanostructures and unsplit-nanosystem. On the other hand, for polarization of the light perpendicular to the long axis of the nanorod, the effect of split gap on the optical responses of the coupled nanosystem is found to be insignificant compared to the parallel polarization. These findings and such geometries suggest that coupling an array of metallic split-ring dimer with long nanorod can resolve the huge radiative loss problem of plasmonic waveguide. In addition, the Fano-like resonances and immense near field enhancements at the split and dimer-rod gaps imply the potentials of the nanosystem for practical applications in localized surface plasmon resonance spectroscopy and sensing.

  10. Scanning optical pyrometer for measuring temperatures in hollow cathodes

    SciTech Connect (OSTI)

    Polk, J. E.; Marrese-Reading, C. M.; Thornber, B.; Dang, L.; Johnson, L. K.; Katz, I.

    2007-09-15

    Life-limiting processes in hollow cathodes are determined largely by the temperature of the electron emitter. To support cathode life assessment, a noncontact temperature measurement technique which employs a stepper motor-driven fiber optic probe was developed. The probe is driven inside the hollow cathode and collects light radiated by the hot interior surface of the emitter. Ratio pyrometry is used to determine the axial temperature profile. Thermocouples on the orifice plate provide measurements of the external temperature during cathode operation and are used to calibrate the pyrometer system in situ with a small oven enclosing the externally heated cathode. The diagnostic method and initial measurements of the temperature distribution in a hollow cathode are discussed.

  11. THz near-field microscopy of graphene structures. (Conference...

    Office of Scientific and Technical Information (OSTI)

    Title: THz near-field microscopy of graphene structures. Abstract not provided. Authors: Pan, Wei ; Brener, Igal ; Mitrofanov, O ; Thompson, R ; Yu, W ; berger, c ; de heer, w.a. ; ...

  12. Apparatus comprising a tunable nanomechanical near-field grating and method for controlling far-field emission

    DOE Patents [OSTI]

    Carr, Dustin Wade; Bogart, Gregory Robert

    2007-02-06

    A tunable nanomechanical near-field grating is disclosed which is capable of varying the intensity of a diffraction mode of an optical output signal. The tunable nanomechanical near-field grating includes two sub-gratings each having line-elements with width and thickness less than the operating wavelength of light with which the grating interacts. Lateral apertures in the two sub-gratings are formed from the space between one line-element of the first sub-grating and at least one line-element of the second sub-grating. One of the sub-gratings is capable of motion such that at least one of aperture width and aperture depth changes, causing a perturbation to the near-field intensity distribution of the tunable nanomechanical near-field grating and a corresponding change to the far-field emission of thereof.

  13. X-ray optics for scanning fluorescence microscopy and other applications

    SciTech Connect (OSTI)

    Ryon, R.W.; Warburton, W.K.

    1992-05-01

    Scanning x-ray fluorescence microscopy is analogous to scanning electron microscopy. Maps of chemical element distribution are produced by scanning with a very small x-ray beam. Goal is to perform such scanning microscopy with resolution in the range of <1 to 10 {mu}m, using standard laboratory x-ray tubes. We are investigating mirror optics in the Kirkpatrick-Baez (K-B) configuration. K-B optics uses two curved mirrors mounted orthogonally along the optical axis. The first mirror provides vertical focus, the second mirror provides horizontal focus. We have used two types of mirrors: synthetic multilayers and crystals. Multilayer mirrors are used with lower energy radiation such as Cu K{alpha}. At higher energies such as Ag K{alpha}, silicon wafers are used in order to increase the incidence angles and thereby the photon collection efficiency. In order to increase the surface area of multilayers which reflects x-rays at the Bragg angle, we have designed mirrors with the spacing between layers graded along the optic axis in order to compensate for the changing angle of incidence. Likewise, to achieve a large reflecting surface with silicon, the wafers are placed on a specially designed lever arm which is bent into a log spiral by applying force at one end. In this way, the same diffracting angle is maintained over the entire surface of the wafer, providing a large solid angle for photon collection.

  14. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P.; Chernobrod, Boris M.

    2010-07-13

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  15. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P.; Chernobrod, Boris M.

    2009-11-10

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of impaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  16. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P.; Chernobrod, Boris M.

    2007-12-11

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  17. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P.; Chernobrod, Boris M.

    2010-06-29

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  18. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P.; Chernobrod, Boris M.

    2009-10-27

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  19. Near-field radiative heat transfer between metamaterials coated with silicon carbide thin films

    SciTech Connect (OSTI)

    Basu, Soumyadipta Yang, Yue; Wang, Liping

    2015-01-19

    In this letter, we study the near-field radiative heat transfer between two metamaterial substrates coated with silicon carbide (SiC) thin films. It is known that metamaterials can enhance the near-field heat transfer over ordinary materials due to excitation of magnetic plasmons associated with s polarization, while strong surface phonon polariton exists for SiC. By careful tuning of the optical properties of metamaterial, it is possible to excite electrical and magnetic resonances for the metamaterial and surface phonon polaritons for SiC at different spectral regions, resulting in the enhanced heat transfer. The effect of the SiC film thickness at different vacuum gaps is investigated. Results obtained from this study will be beneficial for application of thin film coatings for energy harvesting.

  20. 3?m aperture probes for near-field terahertz transmission microscopy...

    Office of Scientific and Technical Information (OSTI)

    3?m aperture probes for near-field terahertz transmission microscopy. Citation Details In-Document Search Title: 3?m aperture probes for near-field terahertz transmission ...

  1. Mechanical Behavior of the Near-field Host Rock Surrounding Excavation...

    Office of Scientific and Technical Information (OSTI)

    Mechanical Behavior of the Near-field Host Rock Surrounding Excavations Citation Details In-Document Search Title: Mechanical Behavior of the Near-field Host Rock Surrounding ...

  2. Near-field effects of asteroid impacts in deep water

    SciTech Connect (OSTI)

    Gisler, Galen R; Weaver, Robert P; Gittings, Michael L

    2009-06-11

    Our previous work has shown that ocean impacts of asteroids below 500 m in diameter do not produce devastating long-distance tsunamis. Nevertheless, a significant portion of the ocean lies close enough to land that near-field effects may prove to be the greatest danger from asteroid impacts in the ocean. Crown splashes and central jets that rise up many kilometres into the atmosphere can produce, upon their collapse, highly non-linear breaking waves that could devastate shorelines within a hundred kilometres of the impact site. We present illustrative calculations, in two and three dimensions, of such impacts for a range of asteroid sizes and impact angles. We find that, as for land impacts, the greatest dangers from oceanic impacts are the short-term near-field, and long-term atmospheric effects.

  3. Near-field NanoThermoMechanical memory

    SciTech Connect (OSTI)

    Elzouka, Mahmoud; Ndao, Sidy

    2014-12-15

    In this letter, we introduce the concept of NanoThermoMechanical Memory. Unlike electronic memory, a NanoThermoMechanical memory device uses heat instead of electricity to record, store, and recover data. Memory function is achieved through the coupling of near-field thermal radiation and thermal expansion resulting in negative differential thermal resistance and thermal latching. Here, we demonstrate theoretically via numerical modeling the concept of near-field thermal radiation enabled negative differential thermal resistance that achieves bistable states. Design and implementation of a practical silicon based NanoThermoMechanical memory device are proposed along with a study of its dynamic response under write/read cycles. With more than 50% of the world's energy losses being in the form of heat along with the ever increasing need to develop computer technologies which can operate in harsh environments (e.g., very high temperatures), NanoThermoMechanical memory and logic devices may hold the answer.

  4. System and method for chromatography and electrophoresis using circular optical scanning

    DOE Patents [OSTI]

    Balch, Joseph W.; Brewer, Laurence R.; Davidson, James C.; Kimbrough, Joseph R.

    2001-01-01

    A system and method is disclosed for chromatography and electrophoresis using circular optical scanning. One or more rectangular microchannel plates or radial microchannel plates has a set of analysis channels for insertion of molecular samples. One or more scanning devices repeatedly pass over the analysis channels in one direction at a predetermined rotational velocity and with a predetermined rotational radius. The rotational radius may be dynamically varied so as to monitor the molecular sample at various positions along a analysis channel. Sample loading robots may also be used to input molecular samples into the analysis channels. Radial microchannel plates are built from a substrate whose analysis channels are disposed at a non-parallel angle with respect to each other. A first step in the method accesses either a rectangular or radial microchannel plate, having a set of analysis channels, and second step passes a scanning device repeatedly in one direction over the analysis channels. As a third step, the scanning device is passed over the analysis channels at dynamically varying distances from a centerpoint of the scanning device. As a fourth step, molecular samples are loaded into the analysis channels with a robot.

  5. Nanomovement of azo polymers induced by metal tip enhanced near-field irradiation

    SciTech Connect (OSTI)

    Ishitobi, Hidekazu; Tanabe, Mamoru; Sekkat, Zouheir; Kawata, Satoshi

    2007-08-27

    Nanomovement of azo polymers induced by metal tip enhanced near-field illumination was studied. A protrusion with 47 nm full width at half maximum was induced with a resolution beyond the diffraction limit. At the top of the protrusion, an anisotropic movement occurs in a direction nearly parallel to the polarization of the incident light, and suggests the existence at the tip end of not only a longitudinal but also a lateral component of the electric field of light. The anisotropic photofluidity and the optical gradient force played important roles in the process of the light induced polymer movement.

  6. High-resolution adaptive optics scanning laser ophthalmoscope with multiple deformable mirrors

    DOE Patents [OSTI]

    Chen, Diana C.; Olivier, Scot S.; Jones; Steven M.

    2010-02-23

    An adaptive optics scanning laser ophthalmoscopes is introduced to produce non-invasive views of the human retina. The use of dual deformable mirrors improved the dynamic range for correction of the wavefront aberrations compared with the use of the MEMS mirror alone, and improved the quality of the wavefront correction compared with the use of the bimorph mirror alone. The large-stroke bimorph deformable mirror improved the capability for axial sectioning with the confocal imaging system by providing an easier way to move the focus axially through different layers of the retina.

  7. Unidirectional wireless power transfer using near-field plates

    SciTech Connect (OSTI)

    Imani, Mohammadreza F.; Grbic, Anthony

    2015-05-14

    One of the obstacles preventing wireless power transfer from becoming ubiquitous is their leakage of power: high-amplitude electromagnetic fields that can interfere with other electronic devices, increase health concerns, or hinder power metering. In this paper, we present near-field plates (NFPs) as a novel method to tailor the electromagnetic fields generated by a wireless power transfer system while maintaining high efficiency. NFPs are modulated arrays or surfaces designed to form prescribed near-field patterns. The NFP proposed in this paper consists of an array of loaded loops that are designed to confine the electromagnetic fields of a resonant transmitting loop to the desired direction (receiving loop) while suppressing fields in other directions. The step-by-step design procedure for this device is outlined. Two NFPs are designed and examined in full-wave simulation. Their performance is shown to be in close agreement with the design predictions, thereby verifying the proposed design and operation. A NFP is also fabricated and experimentally shown to form a unidirectional wireless power transfer link with high efficiency.

  8. Carrier redistribution between different potential sites in semipolar (202{sup ¯}1) InGaN quantum wells studied by near-field photoluminescence

    SciTech Connect (OSTI)

    Marcinkevičius, S.; Gelžinytė, K.; Zhao, Y.; Nakamura, S.; DenBaars, S. P.; Speck, J. S.

    2014-09-15

    Scanning near-field photoluminescence (PL) spectroscopy at different excitation powers was applied to study nanoscale properties of carrier localization and recombination in semipolar (202{sup ¯}1) InGaN quantum wells (QWs) emitting in violet, blue, and green-yellow spectral regions. With increased excitation power, an untypical PL peak energy shift to lower energies was observed. The shift was attributed to carrier density dependent carrier redistribution between nm-scale sites of different potentials. Near-field PL scans showed that in (202{sup ¯}1) QWs the in-plane carrier diffusion is modest, and the recombination properties are uniform, which is advantageous for photonic applications.

  9. Near-field microwave microscopy of high-? oxides grown on graphene with an organic seeding layer

    SciTech Connect (OSTI)

    Tselev, Alexander Kalinin, Sergei V.; Sangwan, Vinod K.; Jariwala, Deep; Lauhon, Lincoln J.; Marks, Tobin J.; Hersam, Mark C.; Department of Chemistry, Northwestern University, Evanston, Illinois 60208

    2013-12-09

    Near-field scanning microwave microscopy (SMM) is used for non-destructive nanoscale characterization of Al{sub 2}O{sub 3} and HfO{sub 2} films grown on epitaxial graphene on SiC by atomic layer deposition using a self-assembled perylene-3,4,9,10-tetracarboxylic dianhydride seeding layer. SMM allows imaging of buried inhomogeneities in the dielectric layer with a spatial resolution close to 100?nm. The results indicate that, while topographic features on the substrate surface cannot be eliminated as possible sites of defect nucleation, the use of a vertically heterogeneous Al{sub 2}O{sub 3}/HfO{sub 2} stack suppresses formation of large outgrowth defects in the oxide film, ultimately improving lateral uniformity of the dielectric film.

  10. Scanning Near-Field Microwave Microscopy of VO2 and CVD Graphene...

    Office of Scientific and Technical Information (OSTI)

    Resource Type: Journal Article Resource Relation: Journal Name: Advanced Materials; Journal Volume: 23; Journal Issue: 20 Research Org: Oak Ridge National Laboratory (ORNL); Center ...

  11. A novel mathematical model for controllable near-field electrospinning

    SciTech Connect (OSTI)

    Ru, Changhai E-mail: luojun@shu.edu.cn; Robotics and Microsystems Center, Soochow University, Suzhou 215021 ; Chen, Jie; Shao, Zhushuai; Pang, Ming; Luo, Jun E-mail: luojun@shu.edu.cn

    2014-01-15

    Near-field electrospinning (NFES) had better controllability than conventional electrospinning. However, due to the lack of guidance of theoretical model, precise deposition of micro/nano fibers could only accomplished by experience. To analyze the behavior of charged jet in NFES using mathematical model, the momentum balance equation was simplified and a new expression between jet cross-sectional radius and axial position was derived. Using this new expression and mass conservation equation, expressions for jet cross-sectional radius and velocity were derived in terms of axial position and initial jet acceleration in the form of exponential functions. Based on Slender-body theory and Giesekus model, a quadratic equation for initial jet acceleration was acquired. With the proposed model, it was able to accurately predict the diameter and velocity of polymer fibers in NFES, and mathematical analysis rather than experimental methods could be applied to study the effects of the process parameters in NFES. Moreover, the movement velocity of the collector stage can be regulated by mathematical model rather than experience. Therefore, the model proposed in this paper had important guiding significance to precise deposition of polymer fibers.

  12. Photoconductive terahertz near-field detector with a hybrid nanoantenna array cavity

    SciTech Connect (OSTI)

    Mitrofanov, Oleg; Brener, Igal; Luk, Ting S.; Reno, John L.

    2015-11-19

    Nanoscale structuring of optical materials leads to modification of their properties and can be used for improving efficiencies of photonic devices and for enabling new functionalities. In ultrafast optoelectronic switches for generation and detection of terahertz (THz) radiation, incorporation of nanostructures allows us to overcome inherent limitations of photoconductive materials. We propose and demonstrate a nanostructured photoconductive THz detector for sampling highly localized THz fields, down to the level of λ/150. The nanostructure that consists of an array of optical nanoantennas and a distributed Bragg reflector forms a hybrid cavity, which traps optical gate pulses within the photoconductive layer. The effect of photon trapping is observed as enhanced absorption at a designed wavelength. This optically thin photoconductive THz detector allows us to detect highly confined evanescent THz fields coupled through a deeply subwavelength aperture as small as 2 μm (λ/150 at 1 THz). As a result, by monolithically integrating the THz detector with apertures ranging from 2 to 5 μm we realize higher spatial resolution and higher sensitivity in aperture-type THz near-field microscopy and THz time-domain spectroscopy.

  13. Photoconductive terahertz near-field detector with a hybrid nanoantenna array cavity

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

    Mitrofanov, Oleg; Brener, Igal; Luk, Ting S.; Reno, John L.

    2015-11-19

    Nanoscale structuring of optical materials leads to modification of their properties and can be used for improving efficiencies of photonic devices and for enabling new functionalities. In ultrafast optoelectronic switches for generation and detection of terahertz (THz) radiation, incorporation of nanostructures allows us to overcome inherent limitations of photoconductive materials. We propose and demonstrate a nanostructured photoconductive THz detector for sampling highly localized THz fields, down to the level of λ/150. The nanostructure that consists of an array of optical nanoantennas and a distributed Bragg reflector forms a hybrid cavity, which traps optical gate pulses within the photoconductive layer. Themore » effect of photon trapping is observed as enhanced absorption at a designed wavelength. This optically thin photoconductive THz detector allows us to detect highly confined evanescent THz fields coupled through a deeply subwavelength aperture as small as 2 μm (λ/150 at 1 THz). As a result, by monolithically integrating the THz detector with apertures ranging from 2 to 5 μm we realize higher spatial resolution and higher sensitivity in aperture-type THz near-field microscopy and THz time-domain spectroscopy.« less

  14. Simultaneous observation of the quantization and the interference pattern of a plasmonic near-field

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

    Piazza, L.; Lummen, T. T. A.; Quiñonez, E.; Murooka, Y.; Reed, B. W.; Barwick, B.; Carbone, F.

    2015-03-02

    Surface plasmon polaritons can confine electromagnetic fields in subwavelength spaces and are of interest for photonics, optical data storage devices and biosensing applications. In analogy to photons, they exhibit wave–particle duality, whose different aspects have recently been observed in separate tailored experiments. Here we demonstrate the ability of ultrafast transmission electron microscopy to simultaneously image both the spatial interference and the quantization of such confined plasmonic fields. Our experiments are accomplished by spatiotemporally overlapping electron and light pulses on a single nanowire suspended on a graphene film. The resulting energy exchange between single electrons and the quanta of the photoinducedmore » near-field is imaged synchronously with its spatial interference pattern. In conclusion, this methodology enables the control and visualization of plasmonic fields at the nanoscale, providing a promising tool for understanding the fundamental properties of confined electromagnetic fields and the development of advanced photonic circuits.« less

  15. Near-field modeling in Frenchman Flat, Nevada Test Site

    SciTech Connect (OSTI)

    Pohlmann, K.; Shirley, C.; Andricevic, R.

    1996-12-01

    The US Department of Energy (DOE) is investigating the effects of nuclear testing in underground test areas (the UGTA program) at the Nevada Test Site. The principal focus of the UGTA program is to better understand and define subsurface radionuclide migration. The study described in this report focuses on the development of tools for generating maps of hydrogeologic characteristics of subsurface Tertiary volcanic units at the Frenchman Flat corrective Action Unit (CAU). The process includes three steps. The first step involves generation of three-dimensional maps of the geologic structure of subsurface volcanic units using geophysical logs to distinguish between two classes: densely welded tuff and nonwelded tuff. The second step generates three-dimensional maps of hydraulic conductivity utilizing the spatial distribution of the two geologic classes obtained in the first step. Each class is described by a correlation structure based on existing data on hydraulic conductivity, and conditioned on the generated spatial location of each class. The final step demonstrates the use of the maps of hydraulic conductivity for modeling groundwater flow and radionuclide transport in volcanic tuffs from an underground nuclear test at the Frenchman Flat CAU. The results indicate that the majority of groundwater flow through the volcanic section occurs through zones of densely welded tuff where connected fractures provide the transport pathway. Migration rates range between near zero to approximately four m/yr, with a mean rate of 0.68 m/yr. This report presents the results of work under the FY96 Near-Field Modeling task of the UGTA program.

  16. Nonlinear optical properties of bulk cuprous oxide using single beam Z-scan at 790?nm

    SciTech Connect (OSTI)

    Serna, J.; Rueda, E.; Garca, H.

    2014-11-10

    The two-photon absorption (TPA) coefficient ? and the nonlinear index of refraction n{sub 2} for bulk cuprous oxide (Cu{sub 2}O) direct gap semiconductor single crystal have been measured by using a balance-detection Z-scan single beam technique, with an excellent signal to noise ratio. Both coefficients were measured at 790?nm using a 65 fs laser pulse at a repetition rate of 90.9?MHz, generated by a Ti:Sapphire laser oscillator. The experimental values for ? were explained by using a model that includes allowed-allowed, forbidden-allowed, and forbidden-forbidden transitions. It was found that the forbidden-forbidden transition is the dominant mechanism, which is consistent with the band structure of Cu{sub 2}O. The low value for ? found in bulk, as compared with respect to thin film, is explained in terms of the structural change in thin films that result in opposite parities of the conduction and valence band. The n{sub 2} is also theoretically calculated by using the TPA dispersion curve and the Kramers-Kronig relations for nonlinear optics.

  17. Scanned Copy

    Office of Environmental Management (EM)

    Scanned Copy

  18. Range-gated imaging for near-field target identification

    SciTech Connect (OSTI)

    Yates, G.J.; Gallegos, R.A.; McDonald, T.E.

    1996-12-01

    The combination of two complementary technologies developed independently at Los Alamos National Laboratory (LANL) and Sandia National Laboratory (SNL) has demonstrated feasibility of target detection and image capture in a highly light-scattering, medium. The technique uses a compact SNL developed Photoconductive Semiconductor Switch/Laser Diode Array (PCSS/LDA) for short-range (distances of 8 to 10 m) large Field-Of-View (FOV) target illumination. Generation of a time-correlated echo signal is accomplished using a photodiode. The return image signal is recorded with a high-speed shuttered Micro-Channel-Plate Image Intensifier (MCPII), declined by LANL and manufactured by Philips Photonics. The MCPII is rated using a high-frequency impedance-matching microstrip design to produce 150 to 200 ps duration optical exposures. The ultra first shuttering producer depth resolution of a few inches along the optic axis between the MCPII and the target, producing enhanced target images effectively deconvolved from noise components from the scattering medium in the FOV. The images from the MCPII are recorded with an RS-170 Charge-Coupled-Device camera and a Big Sky, Beam Code, PC-based digitizer frame grabber and analysis package. Laser pulse data were obtained by the but jitter problems and spectral mismatches between diode spectral emission wavelength and MCPII photocathode spectral sensitivity prevented the capture of fast gating imaging with this demonstration system. Continued development of the system is underway.

  19. Determination of pigments in colour layers on walls of some selected historical buildings using optical and scanning electron microscopy

    SciTech Connect (OSTI)

    Skapin, A. Sever Ropret, P. Bukovec, P.

    2007-11-15

    For successful restoration of painted walls and painted coloured finishing coats it is necessary to determine the composition of the original colour layers. Identification of the pigments used in The Cistercian Abbey of Sticna and The Manor of Novo Celje was carried out using optical and scanning electron microscopy. Selected samples of wall paintings were inspected by the combined application of an optical microscope and a low-vacuum Scanning Electron Microscope to determine their colour and structural features and to identify the position of individual pigment grains. Energy dispersive spectroscopy was used to determine the elemental distribution on selected surfaces and elemental composition of individual pigments. It was found that the most abundantly used pigments were iron oxide red, cinnabar, green earth, umber, calcium carbonate white, ultramarine, yellow ochre and carbon black. These identifications have allowed us to compare the use of various pigments in buildings from different historical periods.

  20. Electromagnetically induced transparency with large delay-bandwidth product induced by magnetic resonance near field coupling to electric resonance

    SciTech Connect (OSTI)

    Li, Hai-ming; Liu, Shao-bin Liu, Si-yuan; Zhang, Hai-feng; Bian, Bo-rui; Kong, Xiang-kun; Wang, Shen-yun

    2015-03-16

    In this paper, we numerically and experimentally demonstrate electromagnetically induced transparency (EIT)-like spectral response with magnetic resonance near field coupling to electric resonance. Six split-ring resonators and a cut wire are chosen as the bright and dark resonator, respectively. An EIT-like transmission peak located between two dips can be observed with incident magnetic field excitation. A large delay bandwidth product (0.39) is obtained, which has potential application in quantum optics and communications. The experimental results are in good agreement with simulated results.

  1. THz near-field microscopy of graphene nano-ribbon arrays. (Conference...

    Office of Scientific and Technical Information (OSTI)

    Title: THz near-field microscopy of graphene nano-ribbon arrays. Authors: Pan, Wei ; Brener, Igal ; Mitrofanov, O. ; Thompson, R ; Yu, W. ; berger, c ; de heer, w.a. ; Jiang, Z. ...

  2. Elucidating the sole contribution from electromagnetic near-fields in plasmon-enhanced Cu2O photocathodes

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

    DuChene, Joseph S.; Williams, Benjamin P.; Johnston-Peck, Aaron C.; Qiu, Jingjing; Gomes, Mathieu; Amilhau, Maxime; Bejleri, Donald; Weng, Jiena; Su, Dong; Huo, Fengwei; et al

    2015-11-05

    Despite many promising reports of plasmon-enhanced photocatalysis, the inability to identify the individual contributions from multiple enhancement mechanisms has delayed the development of general design rules for engineering efficient plasmonic photocatalysts. Herein, we construct a plasmonic photocathode comprised of Au@SiO2 (core@shell) nanoparticles embedded within a Cu2O nanowire network to exclusively examine the contribution from one such mechanism: electromagnetic near-field enhancement. The influence of the local electromagnetic field intensity is correlated with the overall light-harvesting efficiency of the device through variation of the SiO2 shell thickness (5—22 nm) to systematically tailor the distance between the plasmonic Au nanoparticles and the Cu2Omore » nanowires. A three-fold increase in device photocurrent is achieved upon integrating the Au@SiO2 nanoparticles into the Cu2O nanowire network, further enabling a ~40% reduction in semiconductor film thickness while maintaining photocathode performance. Photoelectrochemical results are further correlated with photoluminescence studies and optical simulations to confirm that the near-field enhancement is the sole mechanism responsible for increased light absorption in the plasmonic photocathode.« less

  3. Parallel-plate submicron gap formed by micromachined low-density pillars for near-field radiative heat transfer

    SciTech Connect (OSTI)

    Ito, Kota; Miura, Atsushi; Iizuka, Hideo; Toshiyoshi, Hiroshi

    2015-02-23

    Near-field radiative heat transfer has been a subject of great interest due to the applicability to thermal management and energy conversion. In this letter, a submicron gap between a pair of diced fused quartz substrates is formed by using micromachined low-density pillars to obtain both the parallelism and small parasitic heat conduction. The gap uniformity is validated by the optical interferometry at four corners of the substrates. The heat flux across the gap is measured in a steady-state and is no greater than twice of theoretically predicted radiative heat flux, which indicates that the parasitic heat conduction is suppressed to the level of the radiative heat transfer or less. The heat conduction through the pillars is modeled, and it is found to be limited by the thermal contact resistance between the pillar top and the opposing substrate surface. The methodology to form and evaluate the gap promotes the near-field radiative heat transfer to various applications such as thermal rectification, thermal modulation, and thermophotovoltaics.

  4. Noise analysis for near field 3-D FM-CW radar imaging systems

    SciTech Connect (OSTI)

    Sheen, David M.

    2015-06-19

    Near field radar imaging systems are used for several applications including concealed weapon detection in airports and other high-security venues. Despite the near-field operation, phase noise and thermal noise can limit the performance in several ways including reduction in system sensitivity and reduction of image dynamic range. In this paper, the effects of thermal noise, phase noise, and processing gain are analyzed in the context of a near field 3-D FM-CW imaging radar as might be used for concealed weapon detection. In addition to traditional frequency domain analysis, a time-domain simulation is employed to graphically demonstrate the effect of these noise sources on a fast-chirping FM-CW system.

  5. Electromagnetic Simulation of the Near-Field Distribution around a Wind Farm

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

    Yang, Shang-Te; Ling, Hao

    2013-01-01

    An efficienmore » t approach to compute the near-field distribution around and within a wind farm under plane wave excitation is proposed. To make the problem computationally tractable, several simplifying assumptions are made based on the geometry problem. By comparing the approximations against full-wave simulations at 500 MHz, it is shown that the assumptions do not introduce significant errors into the resulting near-field distribution. The near fields around a 3 × 3 wind farm are computed using the developed methodology at 150 MHz, 500 MHz, and 3 GHz. Both the multipath interference patterns and the forward shadows are predicted by the proposed method.« less

  6. Near-Field Spectroscopy and Imaging of Subwavelength Plasmonic Terahertz Resonators

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

    Mitrofanov, Oleg; Khromova, Irina; Siday, Thomas; Thompson, Robert J.; Ponomarev, Andrey N.; Brener, Igal; Reno, John L.

    2016-04-22

    We describe the temporal evolution of the terahertz (THz) field leading to the excitation of plasmonic resonances in carbon microfibers. The field evolution is mapped in space and time for the 3/2 wavelength resonance using a subwavelength aperture THz near-field probe with an embedded THz photoconductive detector. The excitation of surface waves at the fiber tips leads to the formation of a standing wave along the fiber. Local THz time-domain spectroscopy at one of the standing wave crests shows a clear third-order resonance peak at 1.65 THz, well described by the Lorentz model. Lastly, this application of the subwavelength aperturemore » THz near-field microscopy for mode mapping and local spectroscopy demonstrates the potential of near-field methods for studies of subwavelength plasmonic THz resonators.« less

  7. Near field and altered zone environmental report Volume I: technical bases for EBS design

    SciTech Connect (OSTI)

    Wilder, D. G., LLNL

    1997-08-01

    This report presents an updated summary of results for the waste package (WP) and engineered barrier system (EBS) evaluations, including materials testing, waste-form characterization, EBS performance assessments, and near-field environment (NFE) characterization. Materials testing, design criteria and concept development, and waste-form characterization all require an understanding of the environmental conditions that will interact with the WP and EBS. The Near-Field Environment Report (NFER) was identified in the Waste Package Plan (WPP) (Harrison- Giesler, 1991) as the formal means for transmitting and documenting this information.

  8. Benchmark Modeling of the Near-Field and Far-Field Wave Effects of Wave Energy Arrays

    SciTech Connect (OSTI)

    Rhinefrank, Kenneth E; Haller, Merrick C; Ozkan-Haller, H Tuba

    2013-01-26

    This project is an industry-led partnership between Columbia Power Technologies and Oregon State University that will perform benchmark laboratory experiments and numerical modeling of the near-field and far-field impacts of wave scattering from an array of wave energy devices. These benchmark experimental observations will help to fill a gaping hole in our present knowledge of the near-field effects of multiple, floating wave energy converters and are a critical requirement for estimating the potential far-field environmental effects of wave energy arrays. The experiments will be performed at the Hinsdale Wave Research Laboratory (Oregon State University) and will utilize an array of newly developed Buoys' that are realistic, lab-scale floating power converters. The array of Buoys will be subjected to realistic, directional wave forcing (1:33 scale) that will approximate the expected conditions (waves and water depths) to be found off the Central Oregon Coast. Experimental observations will include comprehensive in-situ wave and current measurements as well as a suite of novel optical measurements. These new optical capabilities will include imaging of the 3D wave scattering using a binocular stereo camera system, as well as 3D device motion tracking using a newly acquired LED system. These observing systems will capture the 3D motion history of individual Buoys as well as resolve the 3D scattered wave field; thus resolving the constructive and destructive wave interference patterns produced by the array at high resolution. These data combined with the device motion tracking will provide necessary information for array design in order to balance array performance with the mitigation of far-field impacts. As a benchmark data set, these data will be an important resource for testing of models for wave/buoy interactions, buoy performance, and far-field effects on wave and current patterns due to the presence of arrays. Under the proposed project we will initiate high

  9. Photon sorting in the near field using subwavelength cavity arrays in the near-infrared

    SciTech Connect (OSTI)

    Mandel, Isroel M. Lansey, Eli; Gollub, Jonah N.; Sarantos, Chris H.; Akhmechet, Roman; Golovin, Andrii B.; Crouse, David T.

    2013-12-16

    A frequency selective metasurface capable of sorting photons in the near-infrared spectral range is designed, fabricated, and characterized. The metasurface, a periodic array of dielectric cylindrical cavities in a gold film, localizes and transmits light of two spectral frequency bands into spatially separated cavities, resulting in near-field light splitting. The design and fabrication methodologies of the metasurface are discussed. The transmittance and photon sorting properties of the designed structure is simulated numerically and the measured transmission is presented.

  10. Laminar and turbulent nozzle-jet flows and their acoustic near-field

    SciTech Connect (OSTI)

    Bhler, Stefan; Obrist, Dominik; Kleiser, Leonhard

    2014-08-15

    We investigate numerically the effects of nozzle-exit flow conditions on the jet-flow development and the near-field sound at a diameter-based Reynolds number of Re{sub D} = 18?100 and Mach number Ma = 0.9. Our computational setup features the inclusion of a cylindrical nozzle which allows to establish a physical nozzle-exit flow and therefore well-defined initial jet-flow conditions. Within the nozzle, the flow is modeled by a potential flow core and a laminar, transitional, or developing turbulent boundary layer. The goal is to document and to compare the effects of the different jet inflows on the jet flow development and the sound radiation. For laminar and transitional boundary layers, transition to turbulence in the jet shear layer is governed by the development of Kelvin-Helmholtz instabilities. With the turbulent nozzle boundary layer, the jet flow development is characterized by a rapid changeover to a turbulent free shear layer within about one nozzle diameter. Sound pressure levels are strongly enhanced for laminar and transitional exit conditions compared to the turbulent case. However, a frequency and frequency-wavenumber analysis of the near-field pressure indicates that the dominant sound radiation characteristics remain largely unaffected. By applying a recently developed scaling procedure, we obtain a close match of the scaled near-field sound spectra for all nozzle-exit turbulence levels and also a reasonable agreement with experimental far-field data.

  11. Geochemistry of Natural Components in the Near-Field Environment, Yucca Mountain, Nevada

    SciTech Connect (OSTI)

    Peterman, Zell E.; Oliver, Thomas A.

    2007-07-01

    The natural near-field environment in and around the emplacement drifts of the proposed nuclear waste repository at Yucca Mountain, Nevada, includes the host rock, dust, seepage, and pore water. The chemical compositions of these components have been determined for assessing possible chemical and mineralogical reactions that may occur after nuclear waste is emplaced. The rock hosting the proposed repository is relatively uniform as shown by a mean coefficient of variation (CV) of 9 percent for major elements. In contrast, compositional variations of dust (bulk and water-soluble fractions), pore water, and seepage are large with mean CVs ranging from 28 to 64 percent. (authors)

  12. Low level absorptance measurements and scans of high performance optical coatings for atomic vapor laser isotope separation applications

    SciTech Connect (OSTI)

    Chow, R.; Taylor, J.R.; Wu, Z.L.; Krupka, R.; Yang, T.

    1998-01-24

    A surface thermal lensing and a radiometric technique was used to characterize the absorptance dependence on time, power, site, and technique of low absorptance optical multilayered coatings.

  13. Indium tin oxide nanowires as hyperbolic metamaterials for near-field radiative heat transfer

    SciTech Connect (OSTI)

    Chang, Jui-Yung; Basu, Soumyadipta Wang, Liping

    2015-02-07

    We investigate near-field radiative heat transfer between Indium Tin Oxide (ITO) nanowire arrays which behave as type 1 and 2 hyperbolic metamaterials. Using spatial dispersion dependent effective medium theory to model the dielectric function of the nanowires, the impact of filling fraction on the heat transfer is analyzed. Depending on the filling fraction, it is possible to achieve both types of hyperbolic modes. At 150?nm vacuum gap, the heat transfer between the nanowires with 0.5 filling fraction can be 11 times higher than that between two bulk ITOs. For vacuum gaps less than 150?nm the heat transfer increases as the filling fraction decreases. Results obtained from this study will facilitate applications of ITO nanowires as hyperbolic metamaterials for energy systems.

  14. Dipolar resonances in conductive carbon micro-fibers probed by near-field terahertz spectroscopy

    SciTech Connect (OSTI)

    Khromova, I.; Navarro-Cía, M.; Brener, I.; Reno, J. L.; Ponomarev, A.; Mitrofanov, O.

    2015-07-13

    In this study, we observe dipole resonances in thin conductive carbon micro-fibers by detecting an enhanced electric field in the near-field of a single fiber at terahertz (THz) frequencies. Time-domain analysis of the electric field shows that each fiber sustains resonant current oscillations at the frequency defined by the fiber's length. Strong dependence of the observed resonance frequency and degree of field enhancement on the fibers' conductive properties enable direct non-contact probing of the THz conductivity in single carbon micro-fibers. We find the conductivity of the fibers to be within the range of 1– 5∙104 S/m. This approach is suitable for experimental characterization of individual doped semiconductor resonators for THz metamaterials and devices.

  15. Dipolar resonances in conductive carbon micro-fibers probed by near-field terahertz spectroscopy

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

    Khromova, I.; Navarro-Cía, M.; Brener, I.; Reno, J. L.; Ponomarev, A.; Mitrofanov, O.

    2015-07-13

    In this study, we observe dipole resonances in thin conductive carbon micro-fibers by detecting an enhanced electric field in the near-field of a single fiber at terahertz (THz) frequencies. Time-domain analysis of the electric field shows that each fiber sustains resonant current oscillations at the frequency defined by the fiber's length. Strong dependence of the observed resonance frequency and degree of field enhancement on the fibers' conductive properties enable direct non-contact probing of the THz conductivity in single carbon micro-fibers. We find the conductivity of the fibers to be within the range of 1– 5∙104 S/m. This approach is suitablemore » for experimental characterization of individual doped semiconductor resonators for THz metamaterials and devices.« less

  16. Near-Field Hydrology Data Package for the Immobilized Low-Activity Waste 2001 Performance Assessment

    SciTech Connect (OSTI)

    PD Meyer; RJ Serne

    1999-12-21

    Lockheed Martin Hanford Company (LMHC) is designing and assessing the performance of disposal facilities to receive radioactive wastes that are currently stored in single- and double-shell tanks at the Hanford Site. The preferred method for disposing of the portion that is classified as immobilized low-activity waste (ILAW) is to vitrify the waste and place the product in new-surface, shallow land burial facilities. The LMHC project to assess the performance of these disposal facilities is the Hanford ILAW Performance Assessment (PA) Activity. The goal of this project is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface water resources, and inadvertent intruders. Achieving this goal will require prediction of contaminant migration from the facilities. This migration is expected to occur primarily via the movement of water through the facilities and the consequent transport of dissolved contaminants in the pore water of the vadose zone. Pacific Northwest National Laboratory (PNNL) assists LMHC in its performance assessment activities. One of PNNL's tasks is to provide estimates of the physical, hydraulic, and transport properties of the materials comprising the disposal facilities and the disturbed region around them. These materials are referred to as the near-field materials. Their properties are expressed as parameters of constitutive models used in simulations of subsurface flow and transport. In addition to the best-estimate parameter values, information on uncertainty in the parameter values and estimates of the changes in parameter values over time are required to complete the PA. These parameter estimates and information are contained in this report, the Near-Field Hydrology Data Package.

  17. Elucidating the sole contribution from electromagnetic near-fields in plasmon-enhanced Cu2O photocathodes

    SciTech Connect (OSTI)

    DuChene, Joseph S.; Williams, Benjamin P.; Johnston-Peck, Aaron C.; Qiu, Jingjing; Gomes, Mathieu; Amilhau, Maxime; Bejleri, Donald; Weng, Jiena; Su, Dong; Huo, Fengwei; Stach, Eric A.; Wei, Wei David

    2015-11-05

    Despite many promising reports of plasmon-enhanced photocatalysis, the inability to identify the individual contributions from multiple enhancement mechanisms has delayed the development of general design rules for engineering efficient plasmonic photocatalysts. Herein, we construct a plasmonic photocathode comprised of Au@SiO2 (core@shell) nanoparticles embedded within a Cu2O nanowire network to exclusively examine the contribution from one such mechanism: electromagnetic near-field enhancement. The influence of the local electromagnetic field intensity is correlated with the overall light-harvesting efficiency of the device through variation of the SiO2 shell thickness (5—22 nm) to systematically tailor the distance between the plasmonic Au nanoparticles and the Cu2O nanowires. A three-fold increase in device photocurrent is achieved upon integrating the Au@SiO2 nanoparticles into the Cu2O nanowire network, further enabling a ~40% reduction in semiconductor film thickness while maintaining photocathode performance. Photoelectrochemical results are further correlated with photoluminescence studies and optical simulations to confirm that the near-field enhancement is the sole mechanism responsible for increased light absorption in the plasmonic photocathode.

  18. Near-field acoustic microbead trapping as remote anchor for single particle manipulation

    SciTech Connect (OSTI)

    Hwang, Jae Youn; Cheon, Dong Young; Shin, Hyunjune; Kim, Hyun Bin; Lee, Jungwoo

    2015-05-04

    We recently proposed an analytical model of a two-dimensional acoustic trapping of polystyrene beads in the ray acoustics regime, where a bead diameter is larger than the wavelength used. As its experimental validation, this paper demonstrates the transverse (or lateral) trapping of individual polystyrene beads in the near field of focused ultrasound. A 100 μm bead is immobilized on the central beam axis by a focused sound beam from a 30 MHz single element lithium niobate transducer, after being laterally displaced through hundreds of micrometers. Maximum displacement, a longest lateral distance at which a trapped bead can be directed towards the central axis, is thus measured over a discrete frequency range from 24 MHz to 36 MHz. The displacement data are found to be between 323.7 μm and 470.2 μm, depending on the transducer's driving frequency and input voltage amplitude. The experimental results are compared with their corresponding model values, and their relative errors lie between 0.9% and 3.9%. The results suggest that this remote maneuvering technique may be employed to manipulate individual cells through solid microbeads, provoking certain cellular reactions to localized mechanical disturbance without direct contact.

  19. Nanomechanical near-field grating apparatus and acceleration sensor formed therefrom

    DOE Patents [OSTI]

    Carr, Dustin Wade; Bogart, Gregory Robert; Keeler, Bianca E. N.

    2008-03-04

    A nanomechanical near-field grating device is disclosed which includes two sub-gratings vertically spaced by a distance less than or equal to an operating wavelength. Each sub-grating includes a plurality of line-elements spaced apart by a distance less than or equal to the operating wavelength. A light source (e.g., a VCSEL or LED) can provide light at the operating wavelength for operation of the device. The device can operate as an active grating, with the intensity of a reflected or transmitted portion of the light varying as the relative positions of the sub-gratings are controlled by an actuator. The device can also operate as a passive grating, with the relative positions of the sub-gratings changing in response to an environmentally-induced force due to acceleration, impact, shock, vibration, gravity, etc. Since the device can be adapted to sense an acceleration that is directed laterally or vertically, a plurality of devices can be located on a common substrate to form a multi-axis acceleration sensor.

  20. Photothermal imaging scanning microscopy

    DOE Patents [OSTI]

    Chinn, Diane; Stolz, Christopher J.; Wu, Zhouling; Huber, Robert; Weinzapfel, Carolyn

    2006-07-11

    Photothermal Imaging Scanning Microscopy produces a rapid, thermal-based, non-destructive characterization apparatus. Also, a photothermal characterization method of surface and subsurface features includes micron and nanoscale spatial resolution of meter-sized optical materials.

  1. Near-Field Hydrology Data Package for the Integrated Disposal Facility 2005 Performance Assessment

    SciTech Connect (OSTI)

    Meyer, Philip D.; Saripalli, Prasad; Freedman, Vicky L.

    2004-06-25

    CH2MHill Hanford Group, Inc. (CHG) is designing and assessing the performance of an Integrated Disposal Facility (IDF) to receive immobilized low-activity waste (ILAW), Low-Level and Mixed Low-Level Wastes (LLW/MLLW), and the Waste Treatment Plant (WTP) melters used to vitrify the ILAW. The IDF Performance Assessment (PA) assesses the performance of the disposal facility to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface water resources, and inadvertent intruders. The PA requires prediction of contaminant migration from the facilities, which is expected to occur primarily via the movement of water through the facilities and the consequent transport of dissolved contaminants in the pore water of the vadose zone. Pacific Northwest National Laboratory (PNNL) assists CHG in its performance assessment activities. One of PNNLs tasks is to provide estimates of the physical, hydraulic, and transport properties of the materials comprising the disposal facilities and the disturbed region around them. These materials are referred to as the near-field materials. Their properties are expressed as parameters of constitutive models used in simulations of subsurface flow and transport. In addition to the best-estimate parameter values, information on uncertainty in the parameter values and estimates of the changes in parameter values over time are required to complete the PA. These parameter estimates and information were previously presented in a report prepared for the 2001 ILAW PA. This report updates the parameter estimates for the 2005 IDF PA using additional information and data collected since publication of the earlier report.

  2. Electromagnetic model for near-field microwave microscope with atomic resolution: Determination of tunnel junction impedance

    SciTech Connect (OSTI)

    Reznik, Alexander N.

    2014-08-25

    An electrodynamic model is proposed for the tunneling microwave microscope with subnanometer space resolution as developed by Lee et al. [Appl. Phys. Lett. 97, 183111 (2010)]. Tip-sample impedance Z{sub a} was introduced and studied in the tunneling and non-tunneling regimes. At tunneling breakdown, the microwave current between probe and sample flows along two parallel channels characterized by impedances Z{sub p} and Z{sub t} that add up to form overall impedance Z{sub a}. Quantity Z{sub p} is the capacitive impedance determined by the near field of the probe and Z{sub t} is the impedance of the tunnel junction. By taking into account the distance dependences of effective tip radius r{sub 0}(z) and tunnel resistance R{sub t}(z)?=?Re[Z{sub t}(z)], we were able to explain the experimentally observed dependences of resonance frequency f{sub r}(z) and quality factor Q{sub L}(z) of the microscope. The obtained microwave resistance R{sub t}(z) and direct current tunnel resistance R{sub t}{sup dc}(z) exhibit qualitatively similar behavior, although being largely different in both magnitude and the characteristic scale of height dependence. Interpretation of the microwave images of the atomic structure of test samples proved possible by taking into account the inductive component of tunnel impedance ImZ{sub t}?=??L{sub t}. Relation ?L{sub t}/R{sub t}???0.235 was obtained.

  3. Report on THMC Modeling of the Near Field Evolution of a Generic Clay Repository: Model Validation and Demonstration Rev 2

    Broader source: Energy.gov [DOE]

    Shale and clay-rich rock formations have been considered as potential host rocks for geological disposal of high-level radioactive waste throughout the world: modeling thermal, hydrological, mechanical, and chemical (THMC) of the near field of generic clay repository is discussed.

  4. Near Field Intensity Trends of Main Laser Alignment Images in the National Ignition Facility (NIF)

    SciTech Connect (OSTI)

    Leach, R R; Beltsar, I; Burkhart, S; Lowe-Webb, R; Kamm, V M; Salmon, T; Wilhelmsen, K

    2015-01-22

    The National Ignition Facility (NIF) utilizes 192 high-energy laser beams focused with enough power and precision on a hydrogen-filled spherical, cryogenic target to potentially initiate a fusion reaction. NIF has been operational for six years; during that time, thousands of successful laser firings or shots have been executed. Critical instrument measurements and camera images are carefully recorded for each shot. The result is a massive and complex database or ‘big data’ archive that can be used to investigate the state of the laser system at any point in its history or to locate and track trends in the laser operation over time. In this study, the optical light throughput for more than 1600 NIF shots for each of the 192 main laser beams and 48 quads was measured over a three year period from January 2009 to October 2012. The purpose was to verify that the variation in the transmission of light through the optics over time performed within design expectations during this time period. Differences between average or integrated intensity from images recorded by the input sensor package (ISP) and by the output sensor package (OSP) in the NIF beam-line were examined. A metric is described for quantifying changes in the integrated intensity measurements and was used to view potential trends. Results are presented for the NIF input and output sensor package trends and changes over the three year time-frame.

  5. The propagation characteristics of electromagnetic waves through plasma in the near-field region of low-frequency loop antenna

    SciTech Connect (OSTI)

    Liu, DongLin Li, XiaoPing; Xie, Kai; Liu, ZhiWei

    2015-10-15

    A high-speed vehicle flying through the atmosphere between 100 and 20 km may suffer from a “communication blackout.” In this paper, a low frequency system with an on-board loop antenna to receive signals is presented as a potential blackout mitigation method. Because the plasma sheath is in the near-field region of the loop antenna, the traditional scattering matrix method that is developed for the far-field region may overestimate the electromagnetic (EM) wave's attenuation. To estimate the EM wave's attenuation in the near-field region, EM interference (EMI) shielding theory is introduced. Experiments are conducted, and the results verify the EMI shielding theory's effectiveness. Simulations are also conducted with different plasma parameters, and the results obtained show that the EM wave's attenuation in the near-field region is far below than that in the far-field region. The EM wave's attenuation increases with the increase in electron density and decreases with the increase in collision frequency. The higher the frequency, the larger is the EM wave's attenuation. During the entire re-entry phase of a RAM-C module, the EM wave's attenuations are below 10 dB for EM waves with a frequency of 1 MHz and below 1 dB for EM waves with a frequency of 100 kHz. Therefore, the low frequency systems (e.g., Loran-C) may provide a way to transmit some key information to high-speed vehicles even during the communication “blackout” period.

  6. Scanning evanescent electro-magnetic microscope

    DOE Patents [OSTI]

    Xiang, Xiao-Dong; Gao, Chen; Schultz, Peter G.; Wei, Tao

    2003-01-01

    A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

  7. Scanning evanescent electro-magnetic microscope

    DOE Patents [OSTI]

    Xiang, Xiao-Dong; Gao, Chen

    2001-01-01

    A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

  8. Scanning Probe Microscopy with Spectroscopic Molecular Recognition - Energy

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

    Innovation Portal Scanning Probe Microscopy with Spectroscopic Molecular Recognition Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryORNL researchers developed an innovative imaging method that possesses the imaging capability of scanning near-field ultrasound holography and the chemical specificity of reverse photoacoustic spectroscopy. This imaging method can achieve chemical differentiation with nanometer resolution. DescriptionAtomic force

  9. Scanning computed confocal imager

    DOE Patents [OSTI]

    George, John S. (Los Alamos, NM)

    2000-03-14

    There is provided a confocal imager comprising a light source emitting a light, with a light modulator in optical communication with the light source for varying the spatial and temporal pattern of the light. A beam splitter receives the scanned light and direct the scanned light onto a target and pass light reflected from the target to a video capturing device for receiving the reflected light and transferring a digital image of the reflected light to a computer for creating a virtual aperture and outputting the digital image. In a transmissive mode of operation the invention omits the beam splitter means and captures light passed through the target.

  10. Optical microspectrometer

    DOE Patents [OSTI]

    Sweatt, William C.; Christenson, Todd R.

    2004-05-25

    An optical microspectrometer comprises a grism to disperse the spectra in a line object. A single optical microspectrometer can be used to sequentially scan a planar object, such as a dye-tagged microchip. Because the optical microspectrometer is very compact, multiple optical microspectrometers can be arrayed to provide simultaneous readout across the width of the planar object The optical microspectrometer can be fabricated with lithographic process, such as deep X-ray lithography (DXRL), with as few as two perpendicular exposures.

  11. Salton Sea Geothermal Field, California, as a near-field natural analog of a radioactive waste repository in salt

    SciTech Connect (OSTI)

    Elders, W.A.; Cohen, L.H.

    1983-11-01

    Since high concentrations of radionuclides and high temperatures are not normally encountered in salt domes or beds, finding an exact geologic analog of expected near-field conditions in a mined nuclear waste repository in salt will be difficult. The Salton Sea Geothermal Field, however, provides an opportunity to investigate the migration and retardation of naturally occurring U, Th, Ra, Cs, Sr and other elements in hot brines which have been moving through clay-rich sedimentary rocks for up to 100,000 years. The more than thirty deep wells drilled in this field to produce steam for electrical generation penetrate sedimentary rocks containing concentrated brines where temperatures reach 365/sup 0/C at only 2 km depth. The brines are primarily Na, K, Ca chlorides with up to 25% of total dissolved solids; they also contain high concentrations of metals such as Fe, Mn, Li, Zn, and Pb. This report describes the geology, geophysics and geochemistry of this system as a prelude to a study of the mobility of naturally occurring radionuclides and radionuclide analogs within it. The aim of this study is to provide data to assist in validating quantitative models of repository behavior and to use in designing and evaluating waste packages and engineered barriers. 128 references, 33 figures, 13 tables.

  12. Near-field thermal radiative transfer and thermoacoustic effects from vapor plumes produced by pulsed CO{sub 2} laser ablation of bulk water

    SciTech Connect (OSTI)

    Kudryashov, S. I.; Lyon, Kevin; Allen, S. D.

    2006-12-15

    Submillimeter deep heating of bulk water by thermal radiation from ablative water plumes produced by a 10.6 {mu}m transversely excited atmospheric CO{sub 2} laser and the related acoustic generation has been studied using a contact time-resolved photoacoustic technique. Effective penetration depths of thermal radiation in water were measured as a function of incident laser fluence and the corresponding plume temperatures were estimated. The near-field thermal and thermoacoustic effects of thermal radiation in laser-ablated bulk water and their potential near-field implications are discussed.

  13. Ultrafast scanning probe microscopy

    DOE Patents [OSTI]

    Weiss, S.; Chemla, D.S.; Ogletree, D.F.; Botkin, D.

    1995-05-16

    An ultrafast scanning probe microscopy method is described for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample. 6 Figs.

  14. Ultrafast scanning probe microscopy

    DOE Patents [OSTI]

    Weiss, Shimon; Chemla, Daniel S.; Ogletree, D. Frank; Botkin, David

    1995-01-01

    An ultrafast scanning probe microscopy method for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample.

  15. Final Technical Report for Interagency Agreement No. DE-SC0005453 “Characterizing Aerosol Distributions, Types, and Optical and Microphysical Properties using the NASA Airborne High Spectral Resolution Lidar (HSRL) and the Research Scanning Polarimeter (RSP)”

    SciTech Connect (OSTI)

    Hostetler, Chris; Ferrare, Richard

    2015-01-13

    Measurements of the vertical profile of atmospheric aerosols and aerosol optical and microphysical characteristics are required to: 1) determine aerosol direct and indirect radiative forcing, 2) compute radiative flux and heating rate profiles, 3) assess model simulations of aerosol distributions and types, and 4) establish the ability of surface and space-based remote sensors to measure the indirect effect. Consequently the ASR program calls for a combination of remote sensing and in situ measurements to determine aerosol properties and aerosol influences on clouds and radiation. As part of our previous DOE ASP project, we deployed the NASA Langley airborne High Spectral Resolution Lidar (HSRL) on the NASA B200 King Air aircraft during major field experiments in 2006 (MILAGRO and MaxTEX), 2007 (CHAPS), 2009 (RACORO), and 2010 (CalNex and CARES). The HSRL provided measurements of aerosol extinction (532 nm), backscatter (532 and 1064 nm), and depolarization (532 and 1064 nm). These measurements were typically made in close temporal and spatial coincidence with measurements made from DOE-funded and other participating aircraft and ground sites. On the RACORO, CARES, and CalNEX missions, we also deployed the NASA Goddard Institute for Space Studies (GISS) Research Scanning Polarimeter (RSP). RSP provided intensity and degree of linear polarization over a broad spectral and angular range enabling column-average retrievals of aerosol optical and microphysical properties. Under this project, we analyzed observations and model results from RACORO, CARES, and CalNex and accomplished the following objectives. 1. Identified aerosol types, characterize the vertical distribution of the aerosol types, and partition aerosol optical depth by type, for CARES and CalNex using HSRL data as we have done for previous missions. 2. Investigated aerosol microphysical and macrophysical properties using the RSP. 3. Used the aerosol backscatter and extinction profiles measured by the HSRL

  16. Reflective optical imaging system

    DOE Patents [OSTI]

    Shafer, David R.

    2000-01-01

    An optical system compatible with short wavelength (extreme ultraviolet) radiation comprising four reflective elements for projecting a mask image onto a substrate. The four optical elements are characterized in order from object to image as convex, concave, convex and concave mirrors. The optical system is particularly suited for step and scan lithography methods. The invention increases the slit dimensions associated with ringfield scanning optics, improves wafer throughput and allows higher semiconductor device density.

  17. Expected near-field thermal environments in a sequentially loaded spent-fuel or high-level waste repository in salt

    SciTech Connect (OSTI)

    Rickertsen, L.D.; Arbital, J.G.; Claiborne, H.C.

    1982-01-01

    This report describes the effect of realistic waste emplacement schedules on repository thermal environments. Virtually all estimates to date have been based on instantaneous loading of wastes having uniform properties throughout the repository. However, more realistic scenarios involving sequential emplacement of wastes reflect the gradual filling of the repository over its lifetime. These cases provide temperatures that can be less extreme than with the simple approximation. At isolated locations in the repository, the temperatures approach the instantaneous-loading limit. However, for most of the repository, temperature rises in the near-field are 10 to 40 years behind the conservative estimates depending on the waste type and the location in the repository. Results are presented for both spent-fuel and high-level reprocessing waste repositories in salt, for a regional repository concept, and for a single national repository concept. The national repository is filled sooner and therefore more closely approximates the instantaneously loaded repository. However, temperatures in the near-field are still 20/sup 0/C or more below the values in the simple model for 40 years after startup of repository emplacement operations. The results suggest that current repository design concepts based on the instantaneous-loading predictions are very conservative. Therefore, experiments to monitor temperatures in a test and evaluation facility, for example, will need to take into account the reduced temperatures in order to provide data used in predicting repository performance.

  18. Analytical scanning evanescent microwave microscope and control stage

    DOE Patents [OSTI]

    Xiang, Xiao-Dong; Gao, Chen; Duewer, Fred; Yang, Hai Tao; Lu, Yalin

    2013-01-22

    A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling. The SEMM can be used to measure electrical properties of both dielectric and electrically conducting materials.

  19. Analytical scanning evanescent microwave microscope and control stage

    DOE Patents [OSTI]

    Xiang, Xiao-Dong; Gao, Chen; Duewer, Fred; Yang, Hai Tao; Lu, Yalin

    2009-06-23

    A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling. The SEMM can be used to measure electrical properties of both dielectric and electrically conducting materials.

  20. Simultaneous near-field and far-field imaging of the 11.9-nm Ni-like Sn soft-x-ray laser

    SciTech Connect (OSTI)

    Staub, F.; Braud, M.; Balmer, J.E.; Nilsen, J.; Bajt, S.

    2004-07-01

    We report on two-dimensional near-field imaging experiments of the 11.9-nm Sn x-ray laser that were performed with a set of Mo/Y multilayer mirrors having reflectivities of up to {approx}45% at normal and at 45 deg. incidence. Second-moment analysis of the x-ray laser emission was used to determine values of the x-ray beam propagation factor M{sup 2} for a range of irradiation parameters. The results reveal a reduction of M{sup 2} with increasing prepulse amplitude. The spatial size of the output is a factor of {approx}2 smaller than previously measured for the 14.7-nm Pd x-ray laser, while the distance of the x-ray emission with respect to the target surface remains roughly the same.

  1. High throughput optical scanner

    DOE Patents [OSTI]

    Basiji, David A. (Seattle, WA); van den Engh, Gerrit J. (Seattle, WA)

    2001-01-01

    A scanning apparatus is provided to obtain automated, rapid and sensitive scanning of substrate fluorescence, optical density or phosphorescence. The scanner uses a constant path length optical train, which enables the combination of a moving beam for high speed scanning with phase-sensitive detection for noise reduction, comprising a light source, a scanning mirror to receive light from the light source and sweep it across a steering mirror, a steering mirror to receive light from the scanning mirror and reflect it to the substrate, whereby it is swept across the substrate along a scan arc, and a photodetector to receive emitted or scattered light from the substrate, wherein the optical path length from the light source to the photodetector is substantially constant throughout the sweep across the substrate. The optical train can further include a waveguide or mirror to collect emitted or scattered light from the substrate and direct it to the photodetector. For phase-sensitive detection the light source is intensity modulated and the detector is connected to phase-sensitive detection electronics. A scanner using a substrate translator is also provided. For two dimensional imaging the substrate is translated in one dimension while the scanning mirror scans the beam in a second dimension. For a high throughput scanner, stacks of substrates are loaded onto a conveyor belt from a tray feeder.

  2. Speckle averaging system for laser raster-scan image projection

    DOE Patents [OSTI]

    Tiszauer, Detlev H.; Hackel, Lloyd A.

    1998-03-17

    The viewers' perception of laser speckle in a laser-scanned image projection system is modified or eliminated by the addition of an optical deflection system that effectively presents a new speckle realization at each point on the viewing screen to each viewer for every scan across the field. The speckle averaging is accomplished without introduction of spurious imaging artifacts.

  3. Speckle averaging system for laser raster-scan image projection

    DOE Patents [OSTI]

    Tiszauer, D.H.; Hackel, L.A.

    1998-03-17

    The viewers` perception of laser speckle in a laser-scanned image projection system is modified or eliminated by the addition of an optical deflection system that effectively presents a new speckle realization at each point on the viewing screen to each viewer for every scan across the field. The speckle averaging is accomplished without introduction of spurious imaging artifacts. 5 figs.

  4. ARM Scanning Radar

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

    (fixed elevation) 3. Sector scan (for cloud tracking) 4. Staring mode 3D-Cloud Products Case Study - Marine Stratocumulus 75 o Horizontal Wind Height In-cloud horizontal wind and...

  5. Solid state optical microscope

    DOE Patents [OSTI]

    Young, Ian T.

    1983-01-01

    A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

  6. Solid state optical microscope

    DOE Patents [OSTI]

    Young, I.T.

    1983-08-09

    A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal. 2 figs.

  7. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, J.M.; Leighton, J.F.

    1988-02-05

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

  8. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, James M.; Leighton, James F.

    1990-01-01

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.

  9. Only critical information was scanned

    Office of Legacy Management (LM)

    Only critical information was scanned. Entire document is available upon request - Click here to email a

  10. Scanning micro-sclerometer

    DOE Patents [OSTI]

    Oliver, Warren C.; Blau, Peter J.

    1994-01-01

    A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch.

  11. Scanning micro-sclerometer

    DOE Patents [OSTI]

    Oliver, W.C.; Blau, P.J.

    1994-11-01

    A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch. 2 figs.

  12. Fly-scan ptychography

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

    Huang, Xiaojing; Lauer, Kenneth; Clark, Jesse N.; Xu, Weihe; Nazaretski, Evgeny; Harder, Ross; Robinson, Ian K.; Chu, Yong S.

    2015-03-13

    We report an experimental ptychography measurement performed in fly-scan mode. With a visible-light laser source, we demonstrate a 5-fold reduction of data acquisition time. By including multiple mutually incoherent modes into the incident illumination, high quality images were successfully reconstructed from blurry diffraction patterns. This approach significantly increases the throughput of ptychography, especially for three-dimensional applications and the visualization of dynamic systems.

  13. Reflective optical imaging method and circuit

    DOE Patents [OSTI]

    Shafer, David R.

    2001-01-01

    An optical system compatible with short wavelength (extreme ultraviolet) radiation comprising four reflective elements for projecting a mask image onto a substrate. The four optical elements are characterized in order from object to image as convex, concave, convex and concave mirrors. The optical system is particularly suited for step and scan lithography methods. The invention increases the slit dimensions associated with ringfield scanning optics, improves wafer throughput and allows higher semiconductor device density.

  14. Molecular near-field antenna effect in resonance hyper-Raman scattering: Intermolecular vibronic intensity borrowing of solvent from solute through dipole-dipole and dipole-quadrupole interactions

    SciTech Connect (OSTI)

    Shimada, Rintaro; Hamaguchi, Hiro-o

    2014-05-28

    We quantitatively interpret the recently discovered intriguing phenomenon related to resonance Hyper-Raman (HR) scattering. In resonance HR spectra of all-trans-?-carotene (?-carotene) in solution, vibrations of proximate solvent molecules are observed concomitantly with the solute ?-carotene HR bands. It has been shown that these solvent bands are subject to marked intensity enhancements by more than 5 orders of magnitude under the presence of ?-carotene. We have called this phenomenon the molecular-near field effect. Resonance HR spectra of ?-carotene in benzene, deuterated benzene, cyclohexane, and deuterated cyclohexane have been measured precisely for a quantitative analysis of this effect. The assignments of the observed peaks are made by referring to the infrared, Raman, and HR spectra of neat solvents. It has been revealed that infrared active and some Raman active vibrations are active in the HR molecular near-field effect. The observed spectra in the form of difference spectra (between benzene/deuterated benzene and cyclohexane/deuterated cyclohexane) are quantitatively analyzed on the basis of the extended vibronic theory of resonance HR scattering. The theory incorporates the coupling of excited electronic states of ?-carotene with the vibrations of a proximate solvent molecule through solutesolvent dipoledipole and dipolequadrupole interactions. It is shown that the infrared active modes arise from the dipoledipole interaction, whereas Raman active modes from the dipolequadrupole interaction. It is also shown that vibrations that give strongly polarized Raman bands are weak in the HR molecular near-field effect. The observed solvent HR spectra are simulated with the help of quantum chemical calculations for various orientations and distances of a solvent molecule with respect to the solute. The observed spectra are best simulated with random orientations of the solvent molecule at an intermolecular distance of 10.

  15. Deep-subwavelength imaging of both electric and magnetic localized optical fields by plasmonic campanile nanoantenna

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

    Caselli, Niccolò; La China, Federico; Bao, Wei; Riboli, Francesco; Gerardino, Annamaria; Li, Lianhe; Linfield, Edmund H.; Pagliano, Francesco; Fiore, Andrea; Schuck, P. James; et al

    2015-06-05

    Tailoring the electromagnetic field at the nanoscale has led to artificial materials exhibiting fascinating optical properties unavailable in naturally occurring substances. Besides having fundamental implications for classical and quantum optics, nanoscale metamaterials provide a platform for developing disruptive novel technologies, in which a combination of both the electric and magnetic radiation field components at optical frequencies is relevant to engineer the light-matter interaction. Thus, an experimental investigation of the spatial distribution of the photonic states at the nanoscale for both field components is of crucial importance. Here we experimentally demonstrate a concomitant deep-subwavelength near-field imaging of the electric and magneticmore » intensities of the optical modes localized in a photonic crystal nanocavity. We take advantage of the “campanile tip”, a plasmonic near-field probe that efficiently combines broadband field enhancement with strong far-field to near-field coupling. In conclusion, by exploiting the electric and magnetic polarizability components of the campanile tip along with the perturbation imaging method, we are able to map in a single measurement both the electric and magnetic localized near-field distributions.« less

  16. Deep-subwavelength imaging of both electric and magnetic localized optical fields by plasmonic campanile nanoantenna

    SciTech Connect (OSTI)

    Caselli, Niccolò; La China, Federico; Bao, Wei; Riboli, Francesco; Gerardino, Annamaria; Li, Lianhe; Linfield, Edmund H.; Pagliano, Francesco; Fiore, Andrea; Schuck, P. James; Cabrini, Stefano; Weber-Bargioni, Alexander; Gurioli, Massimo; Intonti, Francesca

    2015-06-05

    Tailoring the electromagnetic field at the nanoscale has led to artificial materials exhibiting fascinating optical properties unavailable in naturally occurring substances. Besides having fundamental implications for classical and quantum optics, nanoscale metamaterials provide a platform for developing disruptive novel technologies, in which a combination of both the electric and magnetic radiation field components at optical frequencies is relevant to engineer the light-matter interaction. Thus, an experimental investigation of the spatial distribution of the photonic states at the nanoscale for both field components is of crucial importance. Here we experimentally demonstrate a concomitant deep-subwavelength near-field imaging of the electric and magnetic intensities of the optical modes localized in a photonic crystal nanocavity. We take advantage of the “campanile tip”, a plasmonic near-field probe that efficiently combines broadband field enhancement with strong far-field to near-field coupling. In conclusion, by exploiting the electric and magnetic polarizability components of the campanile tip along with the perturbation imaging method, we are able to map in a single measurement both the electric and magnetic localized near-field distributions.

  17. Free motion scanning system

    DOE Patents [OSTI]

    Sword, Charles K.

    2000-01-01

    The present invention relates to an ultrasonic scanner system and method for the imaging of a part system, the scanner comprising: a probe assembly spaced apart from the surface of the part including at least two tracking signals for emitting radiation and a transmitter for emitting ultrasonic waves onto a surface in order to induce at least a portion of the waves to be reflected from the part, at least one detector for receiving the radiation wherein the detector is positioned to receive the radiation from the tracking signals, an analyzer for recognizing a three-dimensional location of the tracking signals based on the emitted radiation, a differential converter for generating an output signal representative of the waveform of the reflected waves, and a device such as a computer for relating said tracking signal location with the output signal and projecting an image of the resulting data. The scanner and method are particularly useful to acquire ultrasonic inspection data by scanning the probe over a complex part surface in an arbitrary scanning pattern.

  18. ARM - Measurement - Aerosol optical depth

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

    Sky-Scanning, Sun Tracking Atmospheric Research SAM : Sun and Aureole Measurement UAV-GNAT : UAV-General Atomics GNAT Value-Added Products AOD : Aerosol Optical Depth, derived from ...

  19. Reflective optical imaging system with balanced distortion

    DOE Patents [OSTI]

    Chapman, Henry N.; Hudyma, Russell M.; Shafer, David R.; Sweeney, Donald W.

    1999-01-01

    An optical system compatible with short wavelength (extreme ultraviolet) An optical system compatible with short wavelength (extreme ultraviolet) radiation comprising four reflective elements for projecting a mask image onto a substrate. The four optical elements comprise, in order from object to image, convex, concave, convex and concave mirrors. The optical system is particularly suited for step and scan lithography methods. The invention enables the use of larger slit dimensions associated with ring field scanning optics, improves wafer throughput and allows higher semiconductor device density. The inventive optical system is characterized by reduced dynamic distortion because the static distortion is balanced across the slit width.

  20. Analysis of Contribution from Edge Radiation to Optical Diffraction Radiation

    SciTech Connect (OSTI)

    C. Liu, P. Evtushenko, A. Freyberger, C. Liu, A.H. Lumpkin

    2009-05-01

    Beam size measurement with near-field optical diffraction radiation (ODR) has been carried out successfully at CEBAF. The ODR station is installed on the Hall-A beam line after eight bending magnets. The ODR images were affected by an unexpected radiation. Some calculations for analyzing the source of the radiation will be presented. Furthermore, two schemes will be proposed to alleviate the contamination.

  1. Spectrometer for Sky-Scanning Sun-Tracking Atmospheric Research (4STAR): Instrument Technology

    SciTech Connect (OSTI)

    Dunagan, Stephen; Johnson, Roy; Zavaleta, Jhony; Russell, P. B.; Schmid, Beat; Flynn, Connor J.; Redemann, Jens; Shinozuka, Yohei; Livingston, J.; Segal Rozenhaimer, Michal

    2013-08-06

    The Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) combines airborne sun tracking and sky scanning with diffraction spectroscopy, to improve knowledge of atmospheric constituents and their links to air-pollution/climate. Direct beam hyper-spectral measurement of optical depth improves retrievals of gas constituents and determination of aerosol properties. Sky scanning enhances retrievals of aerosol type and size distribution. 4STAR measurements will tighten the closure between satellite and ground-based measurements. 4STAR incorporates a modular sun-tracking/ sky-scanning optical head with fiber optic signal transmission to rack mounted spectrometers, permitting miniaturization of the external optical head, and future detector evolution. Technical challenges include compact optical collector design, radiometric dynamic range and stability, and broad spectral coverage. Test results establishing the performance of the instrument against the full range of operational requirements are presented, along with calibration, engineering flight test, and scientific field campaign data and results.

  2. Optical field emission from resonant gold nanorods driven by femtosecond mid-infrared pulses

    SciTech Connect (OSTI)

    Kusa, F.; Echternkamp, K. E.; Herink, G.; Ropers, C.; Ashihara, S.

    2015-07-15

    We demonstrate strong-field photoelectron emission from gold nanorods driven by femtosecond mid-infrared optical pulses. The maximum photoelectron yield is reached at the localized surface plasmon resonance, indicating that the photoemission is governed by the resonantly-enhanced optical near-field. The wavelength- and field-dependent photoemission yield allows for a noninvasive determination of local field enhancements, and we obtain intensity enhancement factors close to 1300, in good agreement with finite-difference time domain computations.

  3. LANL Robotic Vessel Scanning

    SciTech Connect (OSTI)

    Webber, Nels W.

    2015-11-25

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.The project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.

  4. Continuous scanning mode for ptychography

    SciTech Connect (OSTI)

    Clark, Jesse N.; Huang, Xiaojing; Harder, Ross J.; Robinson, Ian K.

    2014-10-15

    We outline how ptychographic imaging can be performed without the need for discrete scan positions. Through an idealized experiment, we demonstrate how a discrete-position scan regime can be replaced with a continuously scanned one with suitable modification of the reconstruction scheme based on coherent modes. The impact of this is that acquisition times can be reduced, significantly aiding ptychographic imaging with x rays, electrons, or visible light.

  5. Reflective optical imaging systems with balanced distortion

    DOE Patents [OSTI]

    Hudyma, Russell M.

    2001-01-01

    Optical systems compatible with extreme ultraviolet radiation comprising four reflective elements for projecting a mask image onto a substrate are described. The four optical elements comprise, in order from object to image, convex, concave, convex and concave mirrors. The optical systems are particularly suited for step and scan lithography methods. The invention enables the use of larger slit dimensions associated with ring field scanning optics, improves wafer throughput, and allows higher semiconductor device density. The inventive optical systems are characterized by reduced dynamic distortion because the static distortion is balanced across the slit width.

  6. ARM: X-Band Scanning ARM Cloud Radar (XSACR) Cross-Wind RHI Scan...

    Office of Scientific and Technical Information (OSTI)

    Cross-Wind RHI Scan Title: ARM: X-Band Scanning ARM Cloud Radar (XSACR) Cross-Wind RHI Scan X-Band Scanning ARM Cloud Radar (XSACR) Cross-Wind RHI Scan Authors: Dan Nelson ; Joseph ...

  7. Lidar arc scan uncertainty reduction through scanning geometry optimization

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

    Wang, H.; Barthelmie, R. J.; Pryor, S. C.; Brown, G.

    2015-10-07

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine powermoreperformance analysis and annual energy production. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation when arc scans are used for wind resource assessment.less

  8. Transverse section radionuclide scanning system

    DOE Patents [OSTI]

    Kuhl, David E.; Edwards, Roy Q.

    1976-01-01

    This invention provides a transverse section radionuclide scanning system for high-sensitivity quantification of brain radioactivity in cross-section picture format in order to permit accurate assessment of regional brain function localized in three-dimensions. High sensitivity crucially depends on overcoming the heretofore known raster type scanning, which requires back and forth detector movement involving dead-time or partial enclosure of the scan field. Accordingly, this invention provides a detector array having no back and forth movement by interlaced detectors that enclose the scan field and rotate as an integral unit around one axis of rotation in a slip ring that continuously transmits the detector data by means of laser emitting diodes, with the advantages that increased amounts of data can be continuously collected, processed and displayed with increased sensitivity according to a suitable computer program.

  9. DECOVALEX-THMC Task D: Long-Term Permeability/Porosity Changes inthe EDZ and Near Field due to THM and THC Processes in Volcanic andCrystaline-Bentonite Systems, Status Report October 2005

    SciTech Connect (OSTI)

    Birkholzer, J.; Rutqvist, J.; Sonnenthal, E.; Barr, D.

    2005-11-01

    The DECOVALEX project is an international cooperativeproject initiated by SKI, the Swedish Nuclear Power Inspectorate, withparticipation of about 10 international organizations. The name DECOVALEXstands for DEvelopment of COupled models and their VALidation againstExperiments. The general goal of this project is to encouragemultidisciplinary interactive and cooperative research on modelingcoupled processes in geologic formations in support of the performanceassessment for underground storage of radioactive waste. Three multi-yearproject stages of DECOVALEX have been completed in the past decade,mainly focusing on coupled thermal-hydrological-mechanicalprocesses.Currently, a fourth three-year project stage of DECOVALEX isunder way, referred to as DECOVALEX-THMC. THMC stands for Thermal,Hydrological, Mechanical, and Chemical processes. The new project stageaims at expanding the traditional geomechanical scope of the previousDECOVALEX project stages by incorporating geochemical processes importantfor repository performance. The U.S. Department of Energy (DOE) leadsTask D of the new DECOVALEX phase, entitled "Long-termPermeability/Porosity Changes in the EDZ and Near Field due to THC andTHM Processes for Volcanic and Crystalline-Bentonite Systems." In itsleadership role for Task D, DOE coordinates and sets the direction forthe cooperative research activities of the international research teamsengaged in Task D.

  10. Final Optics

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

    final optics Final Optics Schematic layout of NIF's final optics assembly (FOA). The suite of optics for one beamline is on the right. The final optics assemblies (FOAs) are the last element of the main laser system and the first of the target area systems. Each FOA contains four integrated optics modules (IOMs) that incorporate beam conditioning, frequency conversion, focusing, diagnostic sampling, and debris shielding capabilities into a single compact assembly. These optics are shown in the

  11. Optical Distance Measurement Device And Method Thereof

    DOE Patents [OSTI]

    Bowers, Mark W.

    2004-06-15

    A system and method of efficiently obtaining distance measurements of a target by scanning the target. An optical beam is provided by a light source and modulated by a frequency source. The modulated optical beam is transmitted to an acousto-optical deflector capable of changing the angle of the optical beam in a predetermined manner to produce an output for scanning the target. In operation, reflected or diffused light from the target may be received by a detector and transmitted to a controller configured to calculate the distance to the target as well as the measurement uncertainty in calculating the distance to the target.

  12. Fiber optic based optical coherence tomography (OCT) for dental applications

    SciTech Connect (OSTI)

    Everett, M. J., LLNL

    1998-06-02

    We have developed a hand-held fiber optic based optical coherence tomography (OCT) system for scanning of the oral cavity We have produced, using this scanning device, in viva cross-sectional images of hard and soft dental tissues in human volunteers Clinically relevant anatomical structures, including the gingival margin, periodontal sulcus, and dento-enamel junction, were visible in all the images The dento-enamel junction and the alveolar bone were identifiable in approximately two thirds of the images These images represent, to our knowledge, the first in viva OCT images of human dental tissue.

  13. Apertureless scanning microscope probe as a detector of semiconductor laser emission

    SciTech Connect (OSTI)

    Dunaevskiy, Mikhail; Dontsov, Anton; Monakhov, Andrei; Alekseev, Prokhor; Titkov, Alexander; Baranov, Alexei; Girard, Paul; Arinero, Richard; Teissier, Roland

    2015-04-27

    An operating semiconductor laser has been studied using a scanning probe microscope. A shift of the resonance frequency of probe that is due to its heating by laser radiation has been analyzed. The observed shift is proportional to the absorbed radiation and can be used to measure the laser near field or its output power. A periodical dependence of the measured signal has been observed as a function of distance between the probe and the surface of the laser due to the interference of the outgoing and cantilever-reflected waves. Due to the multiple reflections resulting in the interference, the light absorption by the probe cantilever is greatly enhanced compared with a single pass case. Interaction of infrared emission of a diode laser with different probes has been studied.

  14. Scanning probe microscopy competency development

    SciTech Connect (OSTI)

    Hawley, M.E.; Reagor, D.W.; Jia, Quan Xi

    1998-12-31

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The project collaborators developed an ultra-high vacuum scanning tunneling microscope (UHV-STM) capability, integrated it with existing scanning probe microscopes, and developed new, advanced air-based scanning force techniques (SPMs). Programmatic, basic, and industrially related laboratory research requires the existence of SPMs, as well as expertise capable of providing local nano-scale information. The UHV-STM capability, equipped with load-lock system and several surface science techniques, will allow introduction, examination, and reaction of surfaces prepared under well-controlled vacuum conditions, including the examination of morphology and local bonding associated with the initial stages of film growth under controlled growth conditions. The resulting capabilities will enable the authors to respond to a variety of problems requiring local characterization of conducting and nonconducting surfaces in liquids, air, and UHV.

  15. Solid-state optical microscope

    DOE Patents [OSTI]

    Young, I.T.

    1981-01-07

    A solid state optical microscope is described wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. Means for scanning in one of two orthogonal directions are provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

  16. Optical extensometer

    DOE Patents [OSTI]

    Walker, Ray A.; Reich, Fred R.; Russell, James T.

    1978-01-01

    An optical extensometer is described using sequentially pulsed light beams for measuring the dimensions of objects by detecting two opposite edges of the object without contacting the object. The light beams may be of different distinguishable light characteristics, such as polarization or wave length, and are time modulated in an alternating manner at a reference frequency. The light characteristics are of substantially the same total light energy and are distributed symmetrically. In the preferred embodiment two light beam segments of one characteristic are on opposite sides of a middle segment of another characteristic. As a result, when the beam segments are scanned sequentially across two opposite edges of the object, they produce a readout signal at the output of a photoelectric detector that is compared with the reference signal by a phase comparator to produce a measurement signal with a binary level transition when the light beams cross an edge. The light beams may be of different cross sectional geometries, including two superimposed and concentric circular beam cross sections of different diameter, or two rectangular cross sections which intersect with each other substantially perpendicular so only their central portions are superimposed. Alternately, a row of three light beams can be used including two outer beams on opposite sides and separate from a middle beam. The three beams may all be of the same light characteristic. However it is preferable that the middle beam be of a different characteristic but of the same total energy as the two outer beams.

  17. Lidar arc scan uncertainty reduction through scanning geometry optimization

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

    Wang, Hui; Barthelmie, Rebecca J.; Pryor, Sara C.; Brown, Gareth.

    2016-04-13

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annualmore » energy production prediction. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30% of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. As a result, large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation.« less

  18. Lidar arc scan uncertainty reduction through scanning geometry optimization

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

    Wang, Hui; Barthelmie, Rebecca J.; Pryor, Sara C.; Brown, Gareth.

    2016-04-13

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annualmore » energy production prediction. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation.« less

  19. Quantum Optics

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

    Energy Frontier Research Centers: Solid-State Lighting Science Center for Frontiers of ... Quantum Optics HomeEnergy ResearchEFRCsSolid-State Lighting Science EFRCQuantum Optics ...

  20. Scanning tunneling microscope nanoetching method

    DOE Patents [OSTI]

    Li, Yun-Zhong; Reifenberger, Ronald G.; Andres, Ronald P.

    1990-01-01

    A method is described for forming uniform nanometer sized depressions on the surface of a conducting substrate. A tunneling tip is used to apply tunneling current density sufficient to vaporize a localized area of the substrate surface. The resulting depressions or craters in the substrate surface can be formed in information encoding patterns readable with a scanning tunneling microscope.

  1. NREL: Measurements and Characterization - Scanning Probe Microscopy

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

    Scanning Probe Microscopy Photo of NREL researcher using scanning probe microscope. Capability of use with ultra-high vacuum makes NREL Scanning Probe Microscopy particularly valuable for certain applications. Scanning probe microscopy (SPM) provides surface images at up to atomic scale and other valuable high-resolution data. SPM encompasses a group of techniques that use very sharp tips that scan extremely closely (several nm) to or in contact with the material being analyzed. The interaction

  2. Method for producing damage resistant optics

    DOE Patents [OSTI]

    Hackel, Lloyd A.; Burnham, Alan K.; Penetrante, Bernardino M.; Brusasco, Raymond M.; Wegner, Paul J.; Hrubesh, Lawrence W.; Kozlowski, Mark R.; Feit, Michael D.

    2003-01-01

    The present invention provides a system that mitigates the growth of surface damage in an optic. Damage to the optic is minimally initiated. In an embodiment of the invention, damage sites in the optic are initiated, located, and then treated to stop the growth of the damage sites. The step of initiating damage sites in the optic includes a scan of the optic using a laser to initiate defects. The exact positions of the initiated sites are identified. A mitigation process is performed that locally or globally removes the cause of subsequent growth of the damaged sites.

  3. Optical probe

    DOE Patents [OSTI]

    Hencken, Kenneth; Flower, William L.

    1999-01-01

    A compact optical probe is disclosed particularly useful for analysis of emissions in industrial environments. The instant invention provides a geometry for optically-based measurements that allows all optical components (source, detector, rely optics, etc.) to be located in proximity to one another. The geometry of the probe disclosed herein provides a means for making optical measurements in environments where it is difficult and/or expensive to gain access to the vicinity of a flow stream to be measured. Significantly, the lens geometry of the optical probe allows the analysis location within a flow stream being monitored to be moved while maintaining optical alignment of all components even when the optical probe is focused on a plurality of different analysis points within the flow stream.

  4. Optical keyboard

    DOE Patents [OSTI]

    Veligdan, James T.; Feichtner, John D.; Phillips, Thomas E.

    2001-01-01

    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.

  5. The Film Scanning and Reanalysis Project

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

    The Film Scanning National Security Science Latest Issue:July 2015 past issues All Issues submit The Film Scanning and Reanalysis Project Scientists on a search-and-rescue...

  6. Three-dimensional scanning confocal laser microscope

    DOE Patents [OSTI]

    Anderson, R. Rox; Webb, Robert H.; Rajadhyaksha, Milind

    1999-01-01

    A confocal microscope for generating an image of a sample includes a first scanning element for scanning a light beam along a first axis, and a second scanning element for scanning the light beam at a predetermined amplitude along a second axis perpendicular to the first axis. A third scanning element scans the light beam at a predetermined amplitude along a third axis perpendicular to an imaging plane defined by the first and second axes. The second and third scanning element are synchronized to scan at the same frequency. The second and third predetermined amplitudes are percentages of their maximum amplitudes. A selector determines the second and third predetermined amplitudes such that the sum of the percentages is equal to one-hundred percent.

  7. NREL: Measurements and Characterization - Scanning Defect Mapping

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

    Photoluminescence Spectroscopy Minority-Carrier Lifetime Spectroscopy Fourier-Transform Infrared & Raman Spectroscopy Spectroscopic Ellipsometry Capacitance Techniques Scanning ...

  8. ARM: X-Band Scanning ARM Cloud Radar (XSACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Dan Nelson; Joseph Hardin; Iosif (Andrei) Lindenmaier; Bradley Isom; Karen Johnson; Nitin Bharadwaj

    X-Band Scanning ARM Cloud Radar (XSACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

  9. ARM: W-Band Scanning ARM Cloud Radar (W-SACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Dan Nelson; Joseph Hardin; Iosif (Andrei) Lindenmaier; Bradley Isom; Karen Johnson; Nitin Bharadwaj

    W-Band Scanning ARM Cloud Radar (W-SACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

  10. ARM: Ka-Band Scanning ARM Cloud Radar (KASACR) Hemispherical Sky RHI Scan (6 horizon-to-horizon scans at 30-degree azimuth intervals)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Dan Nelson; Joseph Hardin; Iosif (Andrei) Lindenmaier; Bradley Isom; Karen Johnson; Nitin Bharadwaj

    Ka-Band Scanning ARM Cloud Radar (KASACR) Hemispherical Sky RHI Scan (6 horizon-to-horizon scans at 30-degree azimuth intervals)

  11. ARM: Ka-Band Scanning ARM Cloud Radar (KASACR) Hemispherical Sky RHI Scan (6 horizon-to-horizon scans at 30-degree azimuth intervals)

    SciTech Connect (OSTI)

    Joseph Hardin; Dan Nelson; Iosif Lindenmaier; Bradley Isom; Karen Johnson; Alyssa Matthews; Nitin Bharadwaj

    2011-05-24

    Ka-Band Scanning ARM Cloud Radar (KASACR) Hemispherical Sky RHI Scan (6 horizon-to-horizon scans at 30-degree azimuth intervals)

  12. ARM: X-Band Scanning ARM Cloud Radar (XSACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

    SciTech Connect (OSTI)

    Dan Nelson; Joseph Hardin; Iosif Lindenmaier; Bradley Isom; Karen Johnson; Nitin Bharadwaj

    2011-09-14

    X-Band Scanning ARM Cloud Radar (XSACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

  13. ARM: W-Band Scanning ARM Cloud Radar (W-SACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Joseph Hardin; Dan Nelson; Iosif (Andrei) Lindenmaier; Bradley Isom; Karen Johnson; Alyssa Matthews; Nitin Bharadwaj

    1990-01-01

    W-Band Scanning ARM Cloud Radar (W-SACR) Hemispherical Sky RHI Scans (6 horizon-to-horizon scans at 30-degree azimuth intervals)

  14. Optical Switch

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

    seven wonders / optical switch Optical Switch A key component in the laser chain, an optical switch called a plasma electrode Pockels cell (PEPC), was invented and developed at LLNL. A Pockels cell rotates the polarization of a laser beam when a voltage is applied across an electro-optic crystal. Depending on the voltage applied, the Pockels cell either allows light to pass through or to reflect off a polarizer, creating an optical switch. For each of NIF's 192 beamlines, a PEPC allows the laser

  15. Scanning ARM Cloud Radar Handbook

    SciTech Connect (OSTI)

    Widener, K; Bharadwaj, N; Johnson, K

    2012-06-18

    The scanning ARM cloud radar (SACR) is a polarimetric Doppler radar consisting of three different radar designs based on operating frequency. These are designated as follows: (1) X-band SACR (X-SACR); (2) Ka-band SACR (Ka-SACR); and (3) W-band SACR (W-SACR). There are two SACRs on a single pedestal at each site where SACRs are deployed. The selection of the operating frequencies at each deployed site is predominantly determined by atmospheric attenuation at the site. Because RF attenuation increases with atmospheric water vapor content, ARM's Tropical Western Pacific (TWP) sites use the X-/Ka-band frequency pair. The Southern Great Plains (SGP) and North Slope of Alaska (NSA) sites field the Ka-/W-band frequency pair. One ARM Mobile Facility (AMF1) has a Ka/W-SACR and the other (AMF2) has a X/Ka-SACR.

  16. Developing new optical imaging techniques for single particle and molecule tracking in live cells

    SciTech Connect (OSTI)

    Sun, Wei

    2010-12-15

    cells. New rotational information was obtained: (1) during endocytosis, cargoes lost their rotation freedom at the late stage of internalization; (2) cargoes performed train-like motion when they were transported along the microtubule network by motor proteins inside live cells; (3) During the pause stage of fast axonal transport, cargoes were still bound to the microtubule tracks by motor proteins. Total internal reflection fluorescence microscopy (TIRFM) is another non-invasive and far-field optical imaging technique. Because of its near-field illumination mechanism, TIRFM has better axial resolution than epi-fluorescence microscopy and confocal microscopy. In this work, an auto-calibrated, prism type, angle-scanning TIRFM instrument was built. The incident angle can range from subcritical angles to nearly 90{sup o}, with an angle interval less than 0.2{sup o}. The angle precision of the new instrument was demonstrated through the finding of the surface plasmon resonance (SPR) angle of metal film coated glass slide. The new instrument improved significantly the precision in determining the axial position. As a result, the best obtained axial resolution was {approx} 8 nm, which is better than current existing instruments similar in function. The instrument was further modified to function as a pseudo TIRF microscope. The illumination depth can be controlled by changing the incident angle of the excitation laser beam or adjusting the horizontal position of the illumination laser spot on the prism top surface. With the new technique, i.e., variable-illumination-depth pseudo TIRF microscopy, the whole cell body from bottom to top was scanned.

  17. New ALS Technique Gives Nanoscale Views of Complex Systems

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

    a newer technique called infrared scattering-scanning near-field optical microscopy (IR s-SNOM) and an older tried-and-true technique called Fourier transform infrared...

  18. Effect of nonlinear absorption on electric field applied lead chloride by Z-scan technique

    SciTech Connect (OSTI)

    Rejeena, I.; Lillibai,; Nampoori, V. P. N.; Radhakrishnan, P.; Rahimkutty, M. H.

    2014-10-15

    The preparation, spectral response and optical nonlinearity of gel grown lead chloride single crystals subjected to electric field of 20V using parallel plate arrangements have been investigated. Optical band gap of the samples were determined using linear absorption spectra. Open aperture z-scan was employed for the determination of nonlinear absorption coefficient of PbCl{sub 2} solution. The normalized transmittance curve exhibits a valley shows reverse saturable absorption. The non linear absorption at different input fluences were recorded using a single Gaussian laser beam in tight focus geometry. The RSA nature of the sample makes it suitable for optical limiting applications.

  19. Flashback: Rapid scanning for radiological threats

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

    Flashback: Rapid scanning for radiological threats Flashback: Rapid scanning for radiological threats The ability to identify distinct material density enables the Multi-Mode Passive Detection System (MMPDS)to quickly detect unshielded to heavily shielded nuclear threats, as well as gamma rays, with near-zero false alarms. November 1, 2015 Decision Science Decision Science Decision Sciences' Multi-Mode Passive Detection System: Rapid scanning forradiological threats Click on headline to go to

  20. NREL: Measurements and Characterization - Scanning Electron Microscopy

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

    Electron Microscopy Researcher using field-emission scanning electron microscope. Field emission scanning electron microscope (FE-SEM) JEOL 6320F. This FE-SEM equipped with a cold field-emission source and in-lens detectors is designed for ultra-high resolution at low accelerating voltage. Compositional mapping by energy-dispersive microscopy and Electron Backscattered Diffraction are available. In basic scanning electron microscopy (SEM), a beam of highly energetic (0.1-50 keV) electrons is

  1. Nanomaterials Analysis using a Scanning Electron Microscope ...

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

    Nanomaterials Analysis using a Scanning Electron Microscope Technology available for licensing: Steradian X-ray detection system increases the detection capability of SEMs during...

  2. Scanned_Agreement.pdf | Department of Energy

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

    Agreement.pdf ScannedAgreement.pdf (625.33 KB) More Documents & Publications MOEDoftheItalianRepublic.PDF InternationalAgreementsJanuary2001December2004.pdf Implementing ...

  3. ScanArc ASA | Open Energy Information

    Open Energy Info (EERE)

    to: navigation, search Name: ScanArc ASA Place: Hoyanger, Norway Product: Norway-based firm that provides advice on and develops processes and applications of plasma energy....

  4. H2Scan LLC | Open Energy Information

    Open Energy Info (EERE)

    search Name: H2Scan LLC Place: Valencia, California Zip: 91355 Sector: Hydro, Hydrogen Product: Hydrogen specific sensing systems, uniquely able to detect hydrogen against...

  5. Fiber optic coupled optical sensor

    DOE Patents [OSTI]

    Fleming, Kevin J. (Albuquerque, NM)

    2001-01-01

    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.

  6. Scanning tunneling microscope assembly, reactor, and system

    DOE Patents [OSTI]

    Tao, Feng; Salmeron, Miquel; Somorjai, Gabor A

    2014-11-18

    An embodiment of a scanning tunneling microscope (STM) reactor includes a pressure vessel, an STM assembly, and three spring coupling objects. The pressure vessel includes a sealable port, an interior, and an exterior. An embodiment of an STM system includes a vacuum chamber, an STM reactor, and three springs. The three springs couple the STM reactor to the vacuum chamber and are operable to suspend the scanning tunneling microscope reactor within the interior of the vacuum chamber during operation of the STM reactor. An embodiment of an STM assembly includes a coarse displacement arrangement, a piezoelectric fine displacement scanning tube coupled to the coarse displacement arrangement, and a receiver. The piezoelectric fine displacement scanning tube is coupled to the coarse displacement arrangement. The receiver is coupled to the piezoelectric scanning tube and is operable to receive a tip holder, and the tip holder is operable to receive a tip.

  7. ARM: X-Band Scanning ARM Cloud Radar (XSACR) RHI Scans, which...

    Office of Scientific and Technical Information (OSTI)

    X-Band Scanning ARM Cloud Radar (XSACR) RHI Scans, which can vary in elevation range and azimuth Authors: Dan Nelson ; Joseph Hardin ; Iosif 1 ; Bradley Isom ; Karen Johnson ; ...

  8. ARM - Field Campaign - NSA Scanning Radar IOP

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

    Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : NSA Scanning Radar IOP ... Low-level mixed-phase clouds, frequently present over the North Slope of Alaska (NSA) ...

  9. Scanning fluorescent microthermal imaging apparatus and method

    DOE Patents [OSTI]

    Barton, Daniel L.; Tangyunyong, Paiboon

    1998-01-01

    A scanning fluorescent microthermal imaging (FMI) apparatus and method is disclosed, useful for integrated circuit (IC) failure analysis, that uses a scanned and focused beam from a laser to excite a thin fluorescent film disposed over the surface of the IC. By collecting fluorescent radiation from the film, and performing point-by-point data collection with a single-point photodetector, a thermal map of the IC is formed to measure any localized heating associated with defects in the IC.

  10. Scanning fluorescent microthermal imaging apparatus and method

    DOE Patents [OSTI]

    Barton, D.L.; Tangyunyong, P.

    1998-01-06

    A scanning fluorescent microthermal imaging (FMI) apparatus and method is disclosed, useful for integrated circuit (IC) failure analysis, that uses a scanned and focused beam from a laser to excite a thin fluorescent film disposed over the surface of the IC. By collecting fluorescent radiation from the film, and performing point-by-point data collection with a single-point photodetector, a thermal map of the IC is formed to measure any localized heating associated with defects in the IC. 1 fig.

  11. Quantum optics with single nanodiamonds flying over gold films: Towards a Robust quantum plasmonics

    SciTech Connect (OSTI)

    Mollet, O.; Drezet, A.; Huant, S.

    2013-12-04

    A nanodiamond (ND) hosting nitrogen-vacancy (NV) color centers is attached on the apex of an optical tip for near-field microscopy. Its fluorescence is used to launch surface plasmon-polaritons (SPPs) in a thin polycrystalline gold film. It is shown that the quantum nature of the initial source of light is preserved after conversion to SPPs. This opens the way to a deterministic quantum plasmonics, where single SPPs can be injected at well-defined positions in a plasmonic device produced by top-down approaches.

  12. Optical characterization of femtosecond laser induced active channel waveguides in lithium fluoride crystals

    SciTech Connect (OSTI)

    Chiamenti, I.; Kalinowski, H. J.; Bonfigli, F.; Montereali, R. M.; Gomes, A. S. L.; Michelotti, F.

    2014-01-14

    We successfully realized broad-band light-emitting color center waveguides buried in LiF crystals by using femtosecond laser pulses. The characterization of the waveguides was performed by optical microscopy, photoluminescence spectra, loss measurements and near-field profiling. The experimental results show that the direct-writing fabrication process induces low-index contrast active channel waveguides: their wavelength-dependent refractive index changes, estimated from 10{sup −3} to 10{sup −4} depending on the writing conditions, allow supporting few modes at visible and near-infrared wavelengths.

  13. Optical coupler

    DOE Patents [OSTI]

    Majewski, Stanislaw; Weisenberger, Andrew G.

    2004-06-15

    In a camera or similar radiation sensitive device comprising a pixilated scintillation layer, a light guide and an array of position sensitive photomultiplier tubes, wherein there exists so-called dead space between adjacent photomultiplier tubes the improvement comprising a two part light guide comprising a first planar light spreading layer or portion having a first surface that addresses the scintillation layer and optically coupled thereto at a second surface that addresses the photomultiplier tubes, a second layer or portion comprising an array of trapezoidal light collectors defining gaps that span said dead space and are individually optically coupled to individual position sensitive photomultiplier tubes. According to a preferred embodiment, coupling of the trapezoidal light collectors to the position sensitive photomultiplier tubes is accomplished using an optical grease having about the same refractive index as the material of construction of the two part light guide.

  14. Optical analyzer

    DOE Patents [OSTI]

    Hansen, A.D.

    1987-09-28

    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.

  15. Optical memory

    DOE Patents [OSTI]

    Mao, Samuel S; Zhang, Yanfeng

    2013-07-02

    Optical memory comprising: a semiconductor wire, a first electrode, a second electrode, a light source, a means for producing a first voltage at the first electrode, a means for producing a second voltage at the second electrode, and a means for determining the presence of an electrical voltage across the first electrode and the second electrode exceeding a predefined voltage. The first voltage, preferably less than 0 volts, different from said second voltage. The semiconductor wire is optically transparent and has a bandgap less than the energy produced by the light source. The light source is optically connected to the semiconductor wire. The first electrode and the second electrode are electrically insulated from each other and said semiconductor wire.

  16. Optical switch

    DOE Patents [OSTI]

    Reedy, Robert P.

    1987-01-01

    An optical switching device (10) is provided whereby light from a first glass fiber (16) or a second glass fiber (14) may be selectively transmitted into a third glass fiber (18). Each glass fiber is provided with a focusing and collimating lens system (26, 28, 30). In one mode of operation, light from the first glass fiber (16) is reflected by a planar mirror (36) into the third glass fiber (18). In another mode of operation, light from the second glass fiber (14) passes directly into the third glass fiber (18). The planar mirror (36) is attached to a rotatable table (32) which is rotated to provide the optical switching.

  17. Optical switch

    DOE Patents [OSTI]

    Reedy, R.P.

    1987-11-10

    An optical switching device is provided whereby light from a first glass fiber or a second glass fiber may be selectively transmitted into a third glass fiber. Each glass fiber is provided with a focusing and collimating lens system. In one mode of operation, light from the first glass fiber is reflected by a planar mirror into the third glass fiber. In another mode of operation, light from the second glass fiber passes directly into the third glass fiber. The planar mirror is attached to a rotatable table which is rotated to provide the optical switching. 3 figs.

  18. Novel Scanning Lens Instrument for Evaluating Fresnel Lens Performance: Equipment Development and Initial Results (Presentation)

    SciTech Connect (OSTI)

    Herrero, R.; Miller, D. C.; Kurtz, S. R.; Anton, I.; Sala, G.

    2013-07-01

    A system dedicated to the optical transmittance characterization of Fresnel lenses has been developed at NREL, in collaboration with the UPM. The system quantifies the optical efficiency of the lens by generating a performance map. The shape of the focused spot may also be analyzed to understand change in the lens performance. The primary instrument components (lasers and CCD detector) have been characterized to confirm their capability for performing optical transmittance measurements. Measurements performed on SoG and PMMA lenses subject to a variety of indoor conditions (e.g., UV and damp heat) identified differences in the optical efficiency of the evaluated lenses, demonstrating the ability of the Scanning Lens Instrument (SLI) to distinguish between the aged lenses.

  19. A simple scanning spectrometer based on a stretchable elastomeric reflective grating

    SciTech Connect (OSTI)

    Ghisleri, C.; Milani, P., E-mail: paolo.milani@mi.infn.it [CIMAINA and Dipartimento di Fisica, Universit di Milano, via Celoria 16, 20133 Milano (Italy); WISE srl, Piazza Duse 2, 20122 Milano (Italy); Potenza, M. A. C.; Bellacicca, A. [CIMAINA and Dipartimento di Fisica, Universit di Milano, via Celoria 16, 20133 Milano (Italy); Ravagnan, L. [WISE srl, Piazza Duse 2, 20122 Milano (Italy)

    2014-02-10

    We report a scanning optical spectrometer based on the use of a stretchable elastomeric reflective grating. The grating is obtained by supersonic cluster beam implantation of silver nanoparticles on polydimethylsiloxane previously grooved by molding to create a replica of a commercial digital versatile disk grating. The use of a stretchable grating allows the spectrometer spanning the whole optical wavelength range by solely extending the diffraction element by more than 100% of its original dimensions. The stretchable reflective optical grating shows excellent performances and stability upon thousands of stretching cycles. The use of this elastomeric element makes the optical layout and the mechanics of the spectrometer extremely simple and advantageous for those applications where spectral resolution is not a major requirement. As a proof of principle, we present the absorption spectrum of Rhodamine B in solution obtained by our spectrometer and compared to commercial instruments.

  20. Optical Measurement Technology For Aluminium Extrusions

    SciTech Connect (OSTI)

    Moe, Per Thomas; Willa-Hansen, Arnfinn; Stoeren, Sigurd

    2007-04-07

    Optical measurement techniques such as laser scanning, structured light scanning and photogrammetry can be used for accurate shape control for aluminum extrusion and downstream processes. The paper presents the fundamentals of optical shape measurement. Furthermore, it focuses on how full-field in- and off-line shape measurement during pure-bending of aluminum extrusions has been performed with stripe projection (structured light) using white light. Full field shape measurement is difficult to implement industrially, but is very useful as a laboratory tool. For example, it has been clearly shown how moderate internal air pressure (less than 5 bars) can significantly reduce undesirable cross-sectional shape distortions during pure bending, and how buckling of the compressive flange occurs at an early stage. Finally, a stretch-bending set-up with adaptive shape control using internal gas pressure and optical techniques is presented.

  1. ARM - Campaign Instrument - scan-irt

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

    govInstrumentsscan-irt Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign Instrument : Scanning IRT (SCAN-IRT) Instrument Categories Radiometric Campaigns Cloudiness Inter-Comparison IOP [ Download Data ] Southern Great Plains, 2003.02.21 - 2003.04.21 Cloudiness Inter-Comparison IOP [ Download Data ] Southern Great Plains, 2003.02.21 - 2003.04.21 Primary Measurements Taken The following measurements are those considered scientifically

  2. Scanning and storage of electrophoretic records

    DOE Patents [OSTI]

    McKean, Ronald A.; Stiegman, Jeff

    1990-01-01

    An electrophoretic record that includes at least one gel separation is mounted for motion laterally of the separation record. A light source is positioned to illuminate at least a portion of the record, and a linear array camera is positioned to have a field of view of the illuminated portion of the record and orthogonal to the direction of record motion. The elements of the linear array are scanned at increments of motion of the record across the field of view to develop a series of signals corresponding to intensity of light at each element at each scan increment.

  3. Quantum Optics

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

    Quantum Optics - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced Nuclear

  4. ARM: X-SAPR Surveillance scan (Dataset) | Data Explorer

    Office of Scientific and Technical Information (OSTI)

    Title: ARM: X-SAPR Surveillance scan X-SAPR Surveillance scan Authors: Widener, Kevin ; Nelson, Dan ; Bharadwaj, Nitin ; Lindenmaier, Iosif 1 ; Collis, Scott + Show Author ...

  5. TSI Model 3936 Scanning Mobility Particle Spectrometer Instrument...

    Office of Scientific and Technical Information (OSTI)

    TSI Model 3936 Scanning Mobility Particle Spectrometer Instrument Handbook Citation Details In-Document Search Title: TSI Model 3936 Scanning Mobility Particle Spectrometer ...

  6. Optical analyzer

    DOE Patents [OSTI]

    Hansen, Anthony D.

    1989-01-01

    An optical analyzer (10) wherein a sample (19) of particulate matter, and particularly of organic matter, which has been collected on a quartz fiber filter (20) is placed in a combustion tube (11), and light from a light source (14) is passed through the sample (19). The temperature of the sample (19) is raised at a controlled rate and in a controlled atmosphere. The magnitude of the transmission of light through the sample (19) is detected (18) as the temperature is raised. A data processor (23), differentiator (28) and a two pen recorder (24) 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 (19). These signatures provide information as to physical and chemical processes and a variety of quantitative and qualitative information about the sample (19). Additional information is obtained by repeating the run in different atmospheres and/or different rates of heating with other samples of the same particulate material collected on other filters.

  7. Apparatus for controlling the scan width of a scanning laser beam

    DOE Patents [OSTI]

    Johnson, Gary W. (Livermore, CA)

    1996-01-01

    Swept-wavelength lasers are often used in absorption spectroscopy applications. In experiments where high accuracy is required, it is desirable to continuously monitor and control the range of wavelengths scanned (the scan width). A system has been demonstrated whereby the scan width of a swept ring-dye laser, or semiconductor diode laser, can be measured and controlled in real-time with a resolution better than 0.1%. Scan linearity, or conformity to a nonlinear scan waveform, can be measured and controlled. The system of the invention consists of a Fabry-Perot interferometer, three CAMAC interface modules, and a microcomputer running a simple analysis and proportional-integral control algorithm. With additional modules, multiple lasers can be simultaneously controlled. The invention also includes an embodiment implemented on an ordinary PC with a multifunction plug-in board.

  8. Apparatus for controlling the scan width of a scanning laser beam

    DOE Patents [OSTI]

    Johnson, G.W.

    1996-10-22

    Swept-wavelength lasers are often used in absorption spectroscopy applications. In experiments where high accuracy is required, it is desirable to continuously monitor and control the range of wavelengths scanned (the scan width). A system has been demonstrated whereby the scan width of a swept ring-dye laser, or semiconductor diode laser, can be measured and controlled in real-time with a resolution better than 0.1%. Scan linearity, or conformity to a nonlinear scan waveform, can be measured and controlled. The system of the invention consists of a Fabry-Perot interferometer, three CAMAC interface modules, and a microcomputer running a simple analysis and proportional-integral control algorithm. With additional modules, multiple lasers can be simultaneously controlled. The invention also includes an embodiment implemented on an ordinary PC with a multifunction plug-in board. 8 figs.

  9. Fiber optic monitoring device

    DOE Patents [OSTI]

    Samborsky, James K.

    1993-01-01

    A device for the purpose of monitoring light transmissions in optical fibers comprises a fiber optic tap that optically diverts a fraction of a transmitted optical signal without disrupting the integrity of the signal. The diverted signal is carried, preferably by the fiber optic tap, to a lens or lens system that disperses the light over a solid angle that facilitates viewing. The dispersed light indicates whether or not the monitored optical fiber or system of optical fibers is currently transmitting optical information.

  10. Cement paste surface roughness analysis using coherence scanning interferometry and confocal microscopy

    SciTech Connect (OSTI)

    Apedo, K.L.; Munzer, C.; He, H.; Montgomery, P.; Serres, N.; Fond, C.; Feugeas, F.

    2015-02-15

    Scanning electron microscopy and scanning probe microscopy have been used for several decades to better understand the microstructure of cementitious materials. Very limited work has been performed to date to study the roughness of cementitious materials by optical microscopy such as coherence scanning interferometry (CSI) and chromatic confocal sensing (CCS). The objective of this paper is to better understand how CSI can be used as a tool to analyze surface roughness and topography of cement pastes. Observations from a series of images acquired using this technique on both polished and unpolished samples are described. The results from CSI are compared with those from a STIL confocal microscopy technique (SCM). Comparison between both optical techniques demonstrates the ability of CSI to measure both polished and unpolished cement pastes. - Highlights: • Coherence scanning interferometry (CSI) was used to analyze cement paste surfaces. • The results from the CSI were compared with those from a confocal microscopy. • 3D roughness parameters were obtained using the window resizing method. • Polished and unpolished cement pastes were studied.

  11. Local extinction and near-field structure in piloted turbulent...

    Office of Scientific and Technical Information (OSTI)

    Additional Journal Information: Journal Volume: 162; Journal Issue: 10; Journal ID: ISSN 0010-2180 Publisher: Elsevier Sponsoring Org: USDOE Office of Science (SC), Basic Energy ...

  12. Electromagnetic Near Field Measurements of Two Critical Assemblies

    SciTech Connect (OSTI)

    Goettee, Jeffrey David

    2015-11-03

    The reactors employed, Godiva IV and WSMR Fast Burst Reactor, are described first. Then the point reactor kinetics model, electromagnetic potential, and the measurement of kinetics quantities are successively discussed. In summary, reactor power produces measurable electric energy. The electric signal mimics power curve for prompt burst operations - features in logarithmic derivatives match. The electric signature should be dependent on the power and not the derivative; therefore, steady-state modes should be measurable.

  13. Power optics

    SciTech Connect (OSTI)

    Apollonov, V V

    2014-02-28

    By using the theory we developed in the early 1970s, a broad range of phenomena is considered for an optical surface of a solid body that is exposed to radiation arbitrarily varying in time and producing temperature fields, thermoelastic stresses and thermal deformations on the surface layer. The examination is based on the relations (which are similar to Duhamel's integral formula from the theory of heat conduction) between the quantities characterising the thermal stress state in any nonstationary regimes of energy input into a solid. A peculiar feature of the analysis of the thermal stress state in this case consists in the fact that this relation comprises time as a parameter, which in turn is a consequence of incoherence of the quasi-stationary problem of thermoelasticity. This phenomenon is particularly important for the optics of high-power, high-pulse repetition rate lasers, which are being actively developed. In the review, we have recently published in Laser Physics, the thermal stress state of a solid is analysed. In this state, time is treated as an independent variable used in differentiation. Such an approach greatly reduces the applicability of the method. The review published contains data on the use of capillary porous structures made of various materials with different degrees of the surface development. Moreover, such structures can be efficiently employed to increase the heat exchange at a temperature below the boiling point of the coolant. In the present review we discuss the dependences of the limiting laser intensities on the duration of a pulse or a pulse train, corresponding to the three stages of the state of the reflecting surface and leading to unacceptable elastic deformations of the surface, to the plastic yield of the material accompanied by the formation of residual stresses and to the melting of the surface layer. We also analyse the problem of heat exchange in the surface layer with a liquid metal coolant pumped through it. The

  14. Vertically aligned nanostructure scanning probe microscope tips

    DOE Patents [OSTI]

    Guillorn, Michael A.; Ilic, Bojan; Melechko, Anatoli V.; Merkulov, Vladimir I.; Lowndes, Douglas H.; Simpson, Michael L.

    2006-12-19

    Methods and apparatus are described for cantilever structures that include a vertically aligned nanostructure, especially vertically aligned carbon nanofiber scanning probe microscope tips. An apparatus includes a cantilever structure including a substrate including a cantilever body, that optionally includes a doped layer, and a vertically aligned nanostructure coupled to the cantilever body.

  15. Parallel optical sampler

    DOE Patents [OSTI]

    Tauke-Pedretti, Anna; Skogen, Erik J; Vawter, Gregory A

    2014-05-20

    An optical sampler includes a first and second 1.times.n optical beam splitters splitting an input optical sampling signal and an optical analog input signal into n parallel channels, respectively, a plurality of optical delay elements providing n parallel delayed input optical sampling signals, n photodiodes converting the n parallel optical analog input signals into n respective electrical output signals, and n optical modulators modulating the input optical sampling signal or the optical analog input signal by the respective electrical output signals, and providing n successive optical samples of the optical analog input signal. A plurality of output photodiodes and eADCs convert the n successive optical samples to n successive digital samples. The optical modulator may be a photodiode interconnected Mach-Zehnder Modulator. A method of sampling the optical analog input signal is disclosed.

  16. Hadamard multimode optical imaging transceiver

    DOE Patents [OSTI]

    Cooke, Bradly J; Guenther, David C; Tiee, Joe J; Kellum, Mervyn J; Olivas, Nicholas L; Weisse-Bernstein, Nina R; Judd, Stephen L; Braun, Thomas R

    2012-10-30

    Disclosed is a method and system for simultaneously acquiring and producing results for multiple image modes using a common sensor without optical filtering, scanning, or other moving parts. The system and method utilize the Walsh-Hadamard correlation detection process (e.g., functions/matrix) to provide an all-binary structure that permits seamless bridging between analog and digital domains. An embodiment may capture an incoming optical signal at an optical aperture, convert the optical signal to an electrical signal, pass the electrical signal through a Low-Noise Amplifier (LNA) to create an LNA signal, pass the LNA signal through one or more correlators where each correlator has a corresponding Walsh-Hadamard (WH) binary basis function, calculate a correlation output coefficient for each correlator as a function of the corresponding WH binary basis function in accordance with Walsh-Hadamard mathematical principles, digitize each of the correlation output coefficient by passing each correlation output coefficient through an Analog-to-Digital Converter (ADC), and performing image mode processing on the digitized correlation output coefficients as desired to produce one or more image modes. Some, but not all, potential image modes include: multi-channel access, temporal, range, three-dimensional, and synthetic aperture.

  17. Optical microphone

    DOE Patents [OSTI]

    Veligdan, James T.

    2000-01-11

    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.

  18. Optical devices

    DOE Patents [OSTI]

    Chaves, Julio C.; Falicoff, Waqidi; Minano, Juan C.; Benitez, Pablo; Dross, Oliver; Parkyn, Jr., William A.

    2010-07-13

    An optical manifold for efficiently combining a plurality of blue LED outputs to illuminate a phosphor for a single, substantially homogeneous output, in a small, cost-effective package. Embodiments are disclosed that use a single or multiple LEDs and a remote phosphor, and an intermediate wavelength-selective filter arranged so that backscattered photoluminescence is recycled to boost the luminance and flux of the output aperture. A further aperture mask is used to boost phosphor luminance with only modest loss of luminosity. Alternative non-recycling embodiments provide blue and yellow light in collimated beams, either separately or combined into white.

  19. Optical microfluidics

    SciTech Connect (OSTI)

    Kotz, K.T.; Noble, K.A.; Faris, G.W. [Molecular Physics Laboratory, SRI International, 333 Ravenswood Avenue, Menlo Park, California 94025 (United States)

    2004-09-27

    We present a method for the control of small droplets based on the thermal Marangoni effect using laser heating. With this approach, droplets covering five orders of magnitude in volume ({approx}1.7 {mu}L to 14 pL), immersed in decanol, were moved on an unmodified polystyrene surface, with speeds of up to 3 mm/s. When two droplets were brought into contact, they spontaneously fused and rapidly mixed in less than 33 ms. This optically addressed microfluidic approach has many advantages for microfluidic transport, including exceptional reconfigurability, low intersample contamination, large volume range, extremely simple substrates, no electrical connections, and ready scaling to large arrays.

  20. Optical interconnect assembly

    DOE Patents [OSTI]

    Laughlin, Daric; Abel, Philip

    2015-06-09

    An optical assembly includes a substrate with a first row of apertures and a second row of apertures. A first optical die includes a first plurality of optical transducer elements and is mounted on the substrate such that an optical signal interface of each transducer element is aligned with an aperture of the first row of optical apertures. A second optical die includes a second plurality of optical transducer elements and is mounted on the substrate such that an optical signal interface of each of the second plurality of optical transducer elements is aligned with an aperture of the second row of optical apertures. A connector configured to mate with the optical assembly supports a plurality of optical fibers. A terminal end of each optical fiber protrudes from the connector and extends into one of the apertures when the connector is coupled with the optical assembly.

  1. Controlling potential barrier height by changing V-shaped pit size and the effect on optical and electrical properties for InGaN/GaN based light-emitting diodes

    SciTech Connect (OSTI)

    Okada, Narihito Kashihara, Hiroyuki; Sugimoto, Kohei; Yamada, Yoichi; Tadatomo, Kazuyuki

    2015-01-14

    The internal quantum efficiency (IQE) of InGaN/GaN multiple quantum wells (MQWs) with blue light emission was improved by inserting an InGaN/GaN superlattice (SL) beneath the MQWs. While the SL technique is useful for improving the light-emitting diode (LED) performance, its effectiveness from a multilateral point of view requires investigation. V-shaped pits (V-pits), which generate a potential barrier and screen the effect of the threading dislocation, are one of the candidates for increasing the light emission efficiency of LEDs exceptionally. In this research, we investigated the relationship between the V-pit and SL and revealed that the V-pit diameter is strongly correlated with the IQE by changing the number of SL periods. Using scanning near-field optical microscopy and photoluminescence measurements, we demonstrated the distinct presence of the potential barrier formed by the V-pits around the dislocations. The relationship between the V-pit and the number of SL periods resulted in changing the potential barrier height, which is related to the V-pit diameter determined by the number of SL periods. In addition, we made an attempt to insert pit expansion layers (PELs) composed of combination of SL and middle temperature grown GaN layer instead of only SL structure. As a result of the evaluation of LEDs using SL or PEL, the EL intensity was strongly related to pit diameter regardless of the structures to form the V-pits. In addition, it was clear that larger V-pits reduce the efficiency droop, which is considered to be suppression of the carrier loss at high injection current.

  2. High-speed massively parallel scanning

    DOE Patents [OSTI]

    Decker, Derek E.

    2010-07-06

    A new technique for recording a series of images of a high-speed event (such as, but not limited to: ballistics, explosives, laser induced changes in materials, etc.) is presented. Such technique(s) makes use of a lenslet array to take image picture elements (pixels) and concentrate light from each pixel into a spot that is much smaller than the pixel. This array of spots illuminates a detector region (e.g., film, as one embodiment) which is scanned transverse to the light, creating tracks of exposed regions. Each track is a time history of the light intensity for a single pixel. By appropriately configuring the array of concentrated spots with respect to the scanning direction of the detection material, different tracks fit between pixels and sufficient lengths are possible which can be of interest in several high-speed imaging applications.

  3. Macroscopic model of scanning force microscope

    DOE Patents [OSTI]

    Guerra-Vela, Claudio; Zypman, Fredy R.

    2004-10-05

    A macroscopic version of the Scanning Force Microscope is described. It consists of a cantilever under the influence of external forces, which mimic the tip-sample interactions. The use of this piece of equipment is threefold. First, it serves as direct way to understand the parts and functions of the Scanning Force Microscope, and thus it is effectively used as an instructional tool. Second, due to its large size, it allows for simple measurements of applied forces and parameters that define the state of motion of the system. This information, in turn, serves to compare the interaction forces with the reconstructed ones, which cannot be done directly with the standard microscopic set up. Third, it provides a kinematics method to non-destructively measure elastic constants of materials, such as Young's and shear modules, with special application for brittle materials.

  4. Laser scanning system for object monitoring

    DOE Patents [OSTI]

    McIntyre, Timothy James [Knoxville, TN; Maxey, Lonnie Curtis [Powell, TN; Chiaro, Jr; John, Peter [Clinton, TN

    2008-04-22

    A laser scanner is located in a fixed position to have line-of-sight access to key features of monitored objects. The scanner rapidly scans pre-programmed points corresponding to the positions of retroreflecting targets affixed to the key features of the objects. The scanner is capable of making highly detailed scans of any portion of the field of view, permitting the exact location and identity of targets to be confirmed. The security of an object is verified by determining that the cooperative target is still present and that its position has not changed. The retroreflecting targets also modulate the reflected light for purposes of returning additional information back to the location of the scanner.

  5. CS-Studio Scan System Parallelization

    SciTech Connect (OSTI)

    Kasemir, Kay; Pearson, Matthew R

    2015-01-01

    For several years, the Control System Studio (CS-Studio) Scan System has successfully automated the operation of beam lines at the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) and Spallation Neutron Source (SNS). As it is applied to additional beam lines, we need to support simultaneous adjustments of temperatures or motor positions. While this can be implemented via virtual motors or similar logic inside the Experimental Physics and Industrial Control System (EPICS) Input/Output Controllers (IOCs), doing so requires a priori knowledge of experimenters requirements. By adding support for the parallel control of multiple process variables (PVs) to the Scan System, we can better support ad hoc automation of experiments that benefit from such simultaneous PV adjustments.

  6. NREL: Measurements and Characterization - Transmission/Scanning

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

    Transmission Electron Microscopy Transmission/Scanning Transmission Electron Microscopy In transmission electron microscopy (TEM), a thin sample, typically less than 200 nm, is bombarded by a highly focused beam of single-energy electrons. The beam has enough energy for the electrons to be transmitted through the sample, and the transmitted or scattered electron signal is greatly magnified by a series of electromagnetic lenses. The magnified signal may be observed by electron diffraction,

  7. Circular zig-zag scan video format

    DOE Patents [OSTI]

    Peterson, C. Glen; Simmons, Charles M.

    1992-01-01

    A circular, ziz-zag scan for use with vidicon tubes. A sine wave is generated, rectified and its fourth root extracted. The fourth root, and its inverse, are used to generate horizontal ramp and sync signals. The fourth root is also used to generate a vertical sync signal, and the vertical sync signal, along with the horizontal sync signal, are used to generate the vertical ramp signal. Cathode blanking and preamplifier clamp signals are also obtained from the vertical sync signal.

  8. Rapid Scan AERI Observations: Benefits and Analysis

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

    Rapid Scan AERI Observations: Benefits and Analysis W. F. Feltz, D. D. Turner, R. O. Knuteson, and R. G. Dedecker Space Science and Engineering Center Cooperative Institute of Mesoscale Meteorological Studies University of Wisconsin-Madison Madison, Wisconsin D. D. Turner Pacific Northwest National Laboratory Richland, Washington Introduction The U.S. Department of Energy's (DOE's) Atmospheric Radiation Measurement (ARM) Program has funded the development of the atmospheric emitted radiance

  9. Scanning magnetoresistance microscopy of atom chips

    SciTech Connect (OSTI)

    Volk, M.; Whitlock, S.; Wolff, C. H.; Hall, B. V.; Sidorov, A. I.

    2008-02-15

    Surface based geometries of microfabricated wires or patterned magnetic films can be used to magnetically trap and manipulate ultracold neutral atoms or Bose-Einstein condensates. We investigate the magnetic properties of such atom chips using a scanning magnetoresistive (MR) microscope with high spatial resolution and high field sensitivity. By comparing MR scans of a permanent magnetic atom chip to field profiles obtained using ultracold atoms, we show that MR sensors are ideally suited to observe small variations of the magnetic field caused by imperfections in the wires or magnetic materials which ultimately lead to fragmentation of ultracold atom clouds. Measurements are also provided for the magnetic field produced by a thin current-carrying wire with small geometric modulations along the edge. Comparisons of our measurements with a full numeric calculation of the current flow in the wire and the subsequent magnetic field show excellent agreement. Our results highlight the use of scanning MR microscopy as a convenient and powerful technique for precisely characterizing the magnetic fields produced near the surface of atom chips.

  10. Optical manifold

    DOE Patents [OSTI]

    Falicoff, Waqidi; Chaves, Julio C.; Minano, Juan Carlos; Benitez, Pablo; Dross, Oliver; Parkyn, Jr., William A.

    2010-02-23

    Optical systems are described that have at least one source of a beam of blue light with divergence under 15.degree.. A phosphor emits yellow light when excited by the blue light. A collimator is disposed with the phosphor and forms a yellow beam with divergence under 15.degree.. A dichroic filter is positioned to transmit the beam of blue light to the phosphor and to reflect the beam of yellow light to an exit aperture. In different embodiments, the beams of blue and yellow light are incident upon said filter with central angles of 15.degree., 22.degree., and 45.degree.. The filter may reflect all of one polarization and part of the other polarization, and a polarization rotating retroreflector may then be provided to return the unreflected light to the filter.

  11. Experimental stress–strain analysis of tapered silica optical fibers with nanofiber waist

    SciTech Connect (OSTI)

    Holleis, S.; Hoinkes, T.; Wuttke, C.; Schneeweiss, P.; Rauschenbeutel, A.

    2014-04-21

    We experimentally determine tensile force–elongation diagrams of tapered optical fibers with a nanofiber waist. The tapered optical fibers are produced from standard silica optical fibers using a heat and pull process. Both, the force–elongation data and scanning electron microscope images of the rupture points indicate a brittle material. Despite the small waist radii of only a few hundred nanometers, our experimental data can be fully explained by a nonlinear stress–strain model that relies on material properties of macroscopic silica optical fibers. This is an important asset when it comes to designing miniaturized optical elements as one can rely on the well-founded material characteristics of standard optical fibers. Based on this understanding, we demonstrate a simple and non-destructive technique that allows us to determine the waist radius of the tapered optical fiber. We find excellent agreement with independent scanning electron microscope measurements of the waist radius.

  12. Optical data latch

    DOE Patents [OSTI]

    Vawter, G. Allen

    2010-08-31

    An optical data latch is formed on a substrate from a pair of optical logic gates in a cross-coupled arrangement in which optical waveguides are used to couple an output of each gate to an photodetector input of the other gate. This provides an optical bi-stability which can be used to store a bit of optical information in the latch. Each optical logic gate, which can be an optical NOT gate (i.e. an optical inverter) or an optical NOR gate, includes a waveguide photodetector electrically connected in series with a waveguide electroabsorption modulator. The optical data latch can be formed on a III-V compound semiconductor substrate (e.g. an InP or GaAs substrate) from III-V compound semiconductor layers. A number of optical data latches can be cascaded to form a clocked optical data shift register.

  13. Circular zig-zag scan video format

    DOE Patents [OSTI]

    Peterson, C.G.; Simmons, C.M.

    1992-06-09

    A circular, ziz-zag scan for use with vidicon tubes is disclosed. A sine wave is generated, rectified and its fourth root extracted. The fourth root, and its inverse, are used to generate horizontal ramp and sync signals. The fourth root is also used to generate a vertical sync signal, and the vertical sync signal, along with the horizontal sync signal, are used to generate the vertical ramp signal. Cathode blanking and preamplifier clamp signals are also obtained from the vertical sync signal. 10 figs.

  14. Copy of Bound Original For Scanning

    Office of Legacy Management (LM)

    Copy of Bound Original For Scanning Document # 1\1\ i g -b DOE/El/-0005/6 Formerly Utilized IVIEWAEC Site! Remedial Action Progrhn, F@diilogical Survey of the Seaway Industrial Par Tonawanda, New Yor May 197 Final Repel Prepared f U.S. Department of Enerc Assistant Secretary for Environme Division of Environmental Control Technolo Washington, D.C. 205, uric Contract No. W-7405-ENG- - - - Available from: ' : -. National Technical Information Service (NTIS) U.S. Department of Comnerce 5285 Port

  15. Optical absorption measurement system

    DOE Patents [OSTI]

    Draggoo, Vaughn G.; Morton, Richard G.; Sawicki, Richard H.; Bissinger, Horst D.

    1989-01-01

    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.

  16. Advanced Optical Technologies

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

    The Advanced Optical Components and Technologies program develops, creates and provides critical optical components for laser-based missions at LLNL. Past projects focused on ...

  17. Optical NAND gate

    DOE Patents [OSTI]

    Skogen, Erik J.; Raring, James; Tauke-Pedretti, Anna

    2011-08-09

    An optical NAND gate is formed from two pair of optical waveguide devices on a substrate, with each pair of the optical waveguide devices consisting of an electroabsorption modulator and a photodetector. One pair of the optical waveguide devices is electrically connected in parallel to operate as an optical AND gate; and the other pair of the optical waveguide devices is connected in series to operate as an optical NOT gate (i.e. an optical inverter). The optical NAND gate utilizes two digital optical inputs and a continuous light input to provide a NAND function output. The optical NAND gate can be formed from III-V compound semiconductor layers which are epitaxially deposited on a III-V compound semiconductor substrate, and operates at a wavelength in the range of 0.8-2.0 .mu.m.

  18. V-119: IBM Security AppScan Enterprise Multiple Vulnerabilities...

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

    9: IBM Security AppScan Enterprise Multiple Vulnerabilities V-119: IBM Security AppScan Enterprise Multiple Vulnerabilities March 26, 2013 - 12:56am Addthis PROBLEM: IBM Security...

  19. REC ScanWafer AS | Open Energy Information

    Open Energy Info (EERE)

    ScanWafer AS Jump to: navigation, search Name: REC ScanWafer AS Place: Hovik, Norway Zip: 1323 Product: Norwegian manufacturer of multicrystalline wafers. Coordinates: 58.002571,...

  20. Smart align -- A new tool for robust non-rigid registration of scanning microscope data

    SciTech Connect (OSTI)

    Jones, Lewys; Yang, Hao; Pennycook, Timothy J.; Marshall, Matthew S. J.; Van Aert, Sandra; Browning, Nigel D.; Castell, Martin R.; Nellist, Peter D.

    2015-07-10

    Many microscopic investigations of materials may benefit from the recording of multiple successive images. This can include techniques common to several types of microscopy such as frame averaging to improve signal-to-noise ratios (SNR) or time series to study dynamic processes or more specific applications. In the scanning transmission electron microscope, this might include focal series for optical sectioning or aberration measurement, beam damage studies or camera-length series to study the effects of strain; whilst in the scanning tunnelling microscope, this might include bias voltage series to probe local electronic structure. Whatever the application, such investigations must begin with the careful alignment of these data stacks, an operation that is not always trivial. In addition, the presence of low-frequency scanning distortions can introduce intra-image shifts to the data. Here, we describe an improved automated method of performing non-rigid registration customised for the challenges unique to scanned microscope data specifically addressing the issues of low-SNR data, images containing a large proportion of crystalline material and/or local features of interest such as dislocations or edges. Careful attention has been paid to artefact testing of the non-rigid registration method used, and the importance of this registration for the quantitative interpretation of feature intensities and positions is evaluated.

  1. Smart align -- A new tool for robust non-rigid registration of scanning microscope data

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

    Jones, Lewys; Yang, Hao; Pennycook, Timothy J.; Marshall, Matthew S. J.; Van Aert, Sandra; Browning, Nigel D.; Castell, Martin R.; Nellist, Peter D.

    2015-07-10

    Many microscopic investigations of materials may benefit from the recording of multiple successive images. This can include techniques common to several types of microscopy such as frame averaging to improve signal-to-noise ratios (SNR) or time series to study dynamic processes or more specific applications. In the scanning transmission electron microscope, this might include focal series for optical sectioning or aberration measurement, beam damage studies or camera-length series to study the effects of strain; whilst in the scanning tunnelling microscope, this might include bias voltage series to probe local electronic structure. Whatever the application, such investigations must begin with the carefulmore » alignment of these data stacks, an operation that is not always trivial. In addition, the presence of low-frequency scanning distortions can introduce intra-image shifts to the data. Here, we describe an improved automated method of performing non-rigid registration customised for the challenges unique to scanned microscope data specifically addressing the issues of low-SNR data, images containing a large proportion of crystalline material and/or local features of interest such as dislocations or edges. Careful attention has been paid to artefact testing of the non-rigid registration method used, and the importance of this registration for the quantitative interpretation of feature intensities and positions is evaluated.« less

  2. Scanning systems for particle cancer therapy

    DOE Patents [OSTI]

    Trbojevic, Dejan

    2015-08-04

    A particle beam to treat malignant tissue is delivered to a patient by a gantry. The gantry includes a plurality of small magnets sequentially arranged along a beam tube to transfer the particle beam with strong focusing and a small dispersion function, whereby a beam size is very small, allowing for the small magnet size. Magnets arranged along the beam tube uses combined function magnets where the magnetic field is a combination of a bending dipole field with a focusing or defocusing quadrupole field. A triplet set of combined function magnets defines the beam size at the patient. A scanning system of magnets arranged along the beam tube after the bending system delivers the particle beam in a direction normal to the patient, to minimize healthy skin and tissue exposure to the particle beam.

  3. Rapid scanning system for fuel drawers

    DOE Patents [OSTI]

    Caldwell, John T.; Fehlau, Paul E.; France, Stephen W.

    1981-01-01

    A nondestructive method for uniqely distinguishing among and quantifying the mass of individual fuel plates in situ in fuel drawers utilized in nuclear reactors is described. The method is both rapid and passive, eliminating the personnel hazard of the commonly used irradiation techniques which require that the analysis be performed in proximity to an intense neutron source such as a reactor. In the present technique, only normally decaying nuclei are observed. This allows the analysis to be performed anywhere. This feature, combined with rapid scanning of a given fuel drawer (in approximately 30 s), and the computer data analysis allows the processing of large numbers of fuel drawers efficiently in the event of a loss alert.

  4. Rapid scanning system for fuel drawers

    DOE Patents [OSTI]

    Caldwell, J.T.; Fehlau, P.E.; France, S.W.

    A nondestructive method for uniquely distinguishing among and quantifying the mass of individual fuel plates in situ in fuel drawers utilized in nuclear reactors is described. The method is both rapid and passive, eliminating the personnel hazard of the commonly used irradiation techniques which require that the analysis be performed in proximity to an intense neutron source such as a reactor. In the present technique, only normally decaying nuclei are observed. This allows the analysis to be performed anywhere. This feature, combined with rapid scanning of a given fuel drawer (in approximately 30 s), and the computer data analysis allows the processing of large numbers of fuel drawers efficiently in the event of a loss alert.

  5. SPIE Optics + Photonics 2011

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

    SPIE Optics + Photonics 2011 August 21-25, 2011 San Diego Convention Center San Diego

  6. Scanning ARM Cloud Radars Part I: Operational Sampling Strategies

    SciTech Connect (OSTI)

    Kollias, Pavlos; Bharadwaj, Nitin; Widener, Kevin B.; Jo, Ieng; Johnson, Karen

    2014-03-01

    Probing clouds in three-dimensions has never been done with scanning millimeter-wavelength (cloud) radars in a continuous operating environment. The acquisition of scanning cloud radars by the Atmospheric Radiation Measurement (ARM) program and research institutions around the world generate the need for developing operational scan strategies for cloud radars. Here, the first generation of sampling strategies for the Scanning ARM Cloud Radars (SACRs) is discussed. These scan strategies are designed to address the scientific objectives of the ARM program, however, they introduce an initial framework for operational scanning cloud radars. While the weather community uses scan strategies that are based on a sequence of scans at constant elevations, the SACRs scan strategies are based on a sequence of scans at constant azimuth. This is attributed to the cloud properties that are vastly different for rain and snow shafts that are the primary target of precipitation radars. A cloud surveillance scan strategy is introduced (HS-RHI) based on a sequence of horizon-to-horizon Range Height Indicator (RHI) scans that sample the hemispherical sky (HS). The HS-RHI scan strategy is repeated every 30 min to provide a static view of the cloud conditions around the SACR location. Between HS-RHI scan strategies other scan strategies are introduced depending on the cloud conditions. The SACRs are pointing vertically in the case of measurable precipitation at the ground. The radar reflectivities are corrected for water vapor attenuation and non-meteorological detection are removed. A hydrometeor detection mask is introduced based on the difference of cloud and noise statistics is discussed.

  7. Optical NOR gate

    DOE Patents [OSTI]

    Skogen, Erik J.; Tauke-Pedretti, Anna

    2011-09-06

    An optical NOR gate is formed from two pair of optical waveguide devices on a substrate, with each pair of the optical waveguide devices consisting of an electroabsorption modulator electrically connected in series with a waveguide photodetector. The optical NOR gate utilizes two digital optical inputs and a continuous light input to provide a NOR function digital optical output. The optical NOR gate can be formed from III-V compound semiconductor layers which are epitaxially deposited on a III-V compound semiconductor substrate, and operates at a wavelength in the range of 0.8-2.0 .mu.m.

  8. Optical XOR gate

    DOE Patents [OSTI]

    Vawter, G. Allen

    2013-11-12

    An optical XOR gate is formed as a photonic integrated circuit (PIC) from two sets of optical waveguide devices on a substrate, with each set of the optical waveguide devices including an electroabsorption modulator electrically connected in series with a waveguide photodetector. The optical XOR gate utilizes two digital optical inputs to generate an XOR function digital optical output. The optical XOR gate can be formed from III-V compound semiconductor layers which are epitaxially deposited on a III-V compound semiconductor substrate, and operates at a wavelength in the range of 0.8-2.0 .mu.m.

  9. Fiber optic connector

    DOE Patents [OSTI]

    Rajic, S.; Muhs, J.D.

    1996-10-22

    A fiber optic connector and method for connecting composite materials within which optical fibers are imbedded are disclosed. The fiber optic connector includes a capillary tube for receiving optical fibers at opposing ends. The method involves inserting a first optical fiber into the capillary tube and imbedding the unit in the end of a softened composite material. The capillary tube is injected with a coupling medium which subsequently solidifies. The composite material is machined to a desired configuration. An external optical fiber is then inserted into the capillary tube after fluidizing the coupling medium, whereby the optical fibers are coupled. 3 figs.

  10. Molecular Foundry

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

    Imaging and Manipulation of Nanostructures This Facility's staff applies and develops techniques to characterize and manipulate a broad variety of nanostructures, from hard to very soft matter, including liquid structures. Imaging methods span electron, optical and scanning probe microscopy, including combined electron-scanning probe and near-field optical-scanning probe instruments. In situ experiments are performed by combining microscopy with manipulation tools and controlled environments.

  11. Calibrating bead displacements in optical tweezers using acousto-optic deflectors

    SciTech Connect (OSTI)

    Vermeulen, Karen C.; Mameren, Joost van; Stienen, Ger J.M.; Peterman, Erwin J.G.; Wuite, Gijs J.L.; Schmidt, Christoph F.

    2006-01-15

    Displacements of optically trapped particles are often recorded using back-focal-plane interferometry. In order to calibrate the detector signals to displacements of the trapped object, several approaches are available. One often relies either on scanning a fixed bead across the waist of the laser beam or on analyzing the power spectrum of movements of the trapped bead. Here, we introduce an alternative method to perform this calibration. The method consists of very rapidly scanning the laser beam across the solvent-immersed, trapped bead using acousto-optic deflectors while recording the detector signals. It does not require any knowledge of solvent viscosity and bead diameter, and works in all types of samples, viscous or viscoelastic. Moreover, it is performed with the same bead as that used in the actual experiment. This represents marked advantages over established methods.

  12. Complete information acquisition in scanning probe microscopy

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

    Belianinov, Alex; Kalinin, Sergei V.; Jesse, Stephen

    2015-03-13

    In the last three decades, scanning probe microscopy (SPM) has emerged as a primary tool for exploring and controlling the nanoworld. A critical part of the SPM measurements is the information transfer from the tip-surface junction to a macroscopic measurement system. This process reduces the many degrees of freedom of a vibrating cantilever to relatively few parameters recorded as images. Similarly, the details of dynamic cantilever response at sub-microsecond time scales of transients, higher-order eigenmodes and harmonics are averaged out by transitioning to millisecond time scale of pixel acquisition. Hence, the amount of information available to the external observer ismore » severely limited, and its selection is biased by the chosen data processing method. Here, we report a fundamentally new approach for SPM imaging based on information theory-type analysis of the data stream from the detector. This approach allows full exploration of complex tip-surface interactions, spatial mapping of multidimensional variability of material s properties and their mutual interactions, and SPM imaging at the information channel capacity limit.« less

  13. Complete information acquisition in scanning probe microscopy

    SciTech Connect (OSTI)

    Belianinov, Alex; Kalinin, Sergei V; Jesse, Stephen

    2015-01-01

    In the last three decades, scanning probe microscopy (SPM) has emerged as a primary tool for exploring and controlling the nanoworld. A critical part of the SPM measurements is the information transfer from the tip-surface junction to a macroscopic measurement system. This process reduces the many degrees of freedom of a vibrating cantilever to relatively few parameters recorded as images. Similarly, the details of dynamic cantilever response at sub-microsecond time scales of transients, higher-order eigenmodes and harmonics are averaged out by transitioning to millisecond time scale of pixel acquisition. Hence, the amount of information available to the external observer is severely limited, and its selection is biased by the chosen data processing method. Here, we report a fundamentally new approach for SPM imaging based on information theory-type analysis of the data stream from the detector. This approach allows full exploration of complex tip-surface interactions, spatial mapping of multidimensional variability of material s properties and their mutual interactions, and SPM imaging at the information channel capacity limit.

  14. Optical Design for Extremely Large Telescope Adaptive Optics...

    Office of Scientific and Technical Information (OSTI)

    Large Telescope Adaptive Optics Systems Citation Details In-Document Search Title: Optical Design for Extremely Large Telescope Adaptive Optics Systems You are accessing a ...

  15. Optical Design for Extremely Large Telescope Adaptive Optics...

    Office of Scientific and Technical Information (OSTI)

    ThesisDissertation: Optical Design for Extremely Large Telescope Adaptive Optics Systems Citation Details In-Document Search Title: Optical Design for Extremely Large Telescope ...

  16. Femtosecond optical clock

    SciTech Connect (OSTI)

    Bagaev, Sergei N; Denisov, Vladimir I; Zakharyash, Valerii F; Kashirsky, Aleksandr V; Klementyev, Vasilii M; Kuznetsov, Sergei A; Korel', I I; Pivtsov, V S

    2004-12-31

    New advances in the field of synthesis of optical frequencies and the development of a new generation of optical clocks are considered. The use of mode-locked femtosecond lasers and fibre emission-spectrum stretchers allows the synthesis of any frequencies (from radio-frequencies to the UV region) and drastically simplifies the structure of an optical clock. The schemes of femtosecond optical clock are presented and the application of tapered optical fibres in them is described. (optical metrology and quantum frequency standards)

  17. Latching micro optical switch

    DOE Patents [OSTI]

    Garcia, Ernest J; Polosky, Marc A

    2013-05-21

    An optical switch reliably maintains its on or off state even when subjected to environments where the switch is bumped or otherwise moved. In addition, the optical switch maintains its on or off state indefinitely without requiring external power. External power is used only to transition the switch from one state to the other. The optical switch is configured with a fixed optical fiber and a movable optical fiber. The movable optical fiber is guided by various actuators in conjunction with a latching mechanism that configure the switch in one position that corresponds to the on state and in another position that corresponds to the off state.

  18. Active optical zoom system

    DOE Patents [OSTI]

    Wick, David V.

    2005-12-20

    An active optical zoom system changes the magnification (or effective focal length) of an optical imaging system by utilizing two or more active optics in a conventional optical system. The system can create relatively large changes in system magnification with very small changes in the focal lengths of individual active elements by leveraging the optical power of the conventional optical elements (e.g., passive lenses and mirrors) surrounding the active optics. The active optics serve primarily as variable focal-length lenses or mirrors, although adding other aberrations enables increased utility. The active optics can either be LC SLMs, used in a transmissive optical zoom system, or DMs, used in a reflective optical zoom system. By appropriately designing the optical system, the variable focal-length lenses or mirrors can provide the flexibility necessary to change the overall system focal length (i.e., effective focal length), and therefore magnification, that is normally accomplished with mechanical motion in conventional zoom lenses. The active optics can provide additional flexibility by allowing magnification to occur anywhere within the FOV of the system, not just on-axis as in a conventional system.

  19. On-the-fly scans for X-ray ptychography

    SciTech Connect (OSTI)

    Pelz, Philipp M.; Guizar-Sicairos, Manuel; Johnson, Ian; Holler, Mirko; Menzel, Andreas; Thibault, Pierre

    2014-12-22

    With the increasing importance of nanotechnology, the need for reliable real-time imaging of mesoscopic objects with nanometer resolution is rising. For X-ray ptychography, a scanning microscopy technique that provides nanometric resolution on extended fields of view, and the settling time of the scanning system is one of the bottlenecks for fast imaging. Here, we demonstrate that ptychographic on-the-fly scans, i.e., collecting diffraction patterns while the sample is scanned with constant velocity, can be modelled as a state mixture of the probing radiation and allow for reliable image recovery. Characteristics of the probe modes are discussed for various scan parameters, and the application to significantly reducing the scanning time is considered.

  20. System and method for compressive scanning electron microscopy

    DOE Patents [OSTI]

    Reed, Bryan W

    2015-01-13

    A scanning transmission electron microscopy (STEM) system is disclosed. The system may make use of an electron beam scanning system configured to generate a plurality of electron beam scans over substantially an entire sample, with each scan varying in electron-illumination intensity over a course of the scan. A signal acquisition system may be used for obtaining at least one of an image, a diffraction pattern, or a spectrum from the scans, the image, diffraction pattern, or spectrum representing only information from at least one of a select subplurality or linear combination of all pixel locations comprising the image. A dataset may be produced from the information. A subsystem may be used for mathematically analyzing the dataset to predict actual information that would have been produced by each pixel location of the image.

  1. ''Atomic Optics'': Nonimaging Optics on the Nanoscale

    SciTech Connect (OSTI)

    Roland Winston Joseph O'Gallagher

    2005-01-15

    This is the final report for a one year close out extension of our basic research program that was established at the University of Chicago more than sixteen years ago to explore and develop the optical sub-discipline that has come to be known as ''nonimaging optics''. This program has been extremely fruitful, having both broadened the range of formalism available for workers in this field and led to the discovery of many new families of optical devices. These devices and techniques have applications wherever the efficient transport and transformation of light distributions are important, in particular in illumination, fiber optics, collection and concentration of sunlight, and the detection of faint light signals in physics and astrophysics. Over the past thirty years, Nonimaging Optics (Welford and Winston, 1989) has brought a fresh approach to the analysis of many problems in classical macro-scale optics. Through the application of phase-space concepts, statistical methods, thermodynamic arguments, etc., many previously established performance limits were able to be broken and many technical surprises with exciting practical applications were discovered. The most recent three-year phase of our long-term continuing program ended in late 2002 and emphasized extending our work in geometrical optics and expanding it to include some interesting questions in physical optics as well as in the new field of statistical optics. This report presents a survey of the basic history and concepts of nonimaging optics and reviews highlights and significant accomplishments over the past fifteen years. This is followed by a more detailed summary of recent research directions and accomplishments during the last three years. This most recent phase was marked by the broadening in scope to include a separate project involving a collaboration with an industrial partner, Science Applications International Corporation (SAIC). This effort was proposed and approved in 1998 and was

  2. Results from Vernier scans during the RHIC 2008 PP Run

    SciTech Connect (OSTI)

    Drees,A.; D Ottavio, T.

    2009-05-04

    Using the vernier scan or Van der Meer scan technique, where one beam is swept stepwise across the other while measuring the collision rate as a function of beam displacement, the transverse beam profiles, the luminosity and the effective cross section of the detector in question can be measured. This report briefly recalls the vernier scan method and presents results from the 100 GeV 2008 RHIC polarized proton (pp) run.

  3. High bandwidth optical mount

    DOE Patents [OSTI]

    Bender, D.A.; Kuklo, T.

    1994-11-08

    An optical mount, which directs a laser beam to a point by controlling the position of a light-transmitting optic, is stiffened so that a lowest resonant frequency of the mount is approximately one kilohertz. The optical mount, which is cylindrically-shaped, positions the optic by individually moving a plurality of carriages which are positioned longitudinally within a sidewall of the mount. The optical mount is stiffened by allowing each carriage, which is attached to the optic, to move only in a direction which is substantially parallel to a center axis of the optic. The carriage is limited to an axial movement by flexures or linear bearings which connect the carriage to the mount. The carriage is moved by a piezoelectric transducer. By limiting the carriage to axial movement, the optic can be kinematically clamped to a carriage. 5 figs.

  4. High bandwidth optical mount

    DOE Patents [OSTI]

    Bender, Donald A.; Kuklo, Thomas

    1994-01-01

    An optical mount, which directs a laser beam to a point by controlling the position of a light-transmitting optic, is stiffened so that a lowest resonant frequency of the mount is approximately one kilohertz. The optical mount, which is cylindrically-shaped, positions the optic by individually moving a plurality of carriages which are positioned longitudinally within a sidewall of the mount. The optical mount is stiffened by allowing each carriage, which is attached to the optic, to move only in a direction which is substantially parallel to a center axis of the optic. The carriage is limited to an axial movement by flexures or linear bearings which connect the carriage to the mount. The carriage is moved by a piezoelectric transducer. By limiting the carriage to axial movement, the optic can be kinematically clamped to a carriage.

  5. Demonstration of scan path optimization in proton therapy

    SciTech Connect (OSTI)

    Kang, Joanne H.; Wilkens, Jan J.; Oelfke, Uwe

    2007-09-15

    A three-dimensional (3D) intensity modulated proton therapy treatment plan to be delivered by magnetic scanning may comprise thousands of discrete beam positions. This research presents the minimization of the total scan path length by application of a fast simulated annealing (FSA) optimization algorithm. Treatment plans for clinical prostate and head and neck cases were sequenced for continuous raster scanning in two ways, and the resulting scan path lengths were compared: (1) A simple back-and-forth, top-to-bottom (zigzag) succession, and (2) an optimized path produced as a solution of the FSA algorithm. Using a first approximation of the scanning dynamics, the delivery times for the scan sequences before and after path optimization were calculated for comparison. In these clinical examples, the FSA optimization shortened the total scan path length for the 3D target volumes by approximately 13%-56%. The number of extraneous spilled particles was correspondingly reduced by about 13%-54% due to the more efficient scanning maps that eliminated multiple crossings through regions of zero fluence. The relative decrease in delivery time due to path length minimization was estimated to be less than 1%, due to both a high scanning speed and time requirements that could not be altered by optimization (e.g., time required to change the beam energy). In a preliminary consideration of application to rescanning techniques, the decrease in delivery time was estimated to be 4%-20%.

  6. ARM: AOS: Scanning-Mobility Particle Sizer; temperature and RH...

    Office of Scientific and Technical Information (OSTI)

    AOS: Scanning-Mobility Particle Sizer; temperature and RH output Authors: Derek Hageman ; Bill Behrens ; Janek Uin ; Robert Bullard ; Cynthia Salwen ; Cynthia Salwen ; Annette ...

  7. Deployment of ARM Aerial Facility (AAF) Scanning Mobility Particle...

    Office of Scientific and Technical Information (OSTI)

    Mobility Particle Sizer Field Campaign Report Citation Details In-Document Search Title: Deployment of ARM Aerial Facility (AAF) Scanning Mobility Particle Sizer Field ...

  8. Multi-level scanning method for defect inspection

    DOE Patents [OSTI]

    Bokor, Jeffrey; Jeong, Seongtae

    2002-01-01

    A method for performing scanned defect inspection of a collection of contiguous areas using a specified false-alarm-rate and capture-rate within an inspection system that has characteristic seek times between inspection locations. The multi-stage method involves setting an increased false-alarm-rate for a first stage of scanning, wherein subsequent stages of scanning inspect only the detected areas of probable defects at lowered values for the false-alarm-rate. For scanning inspection operations wherein the seek time and area uncertainty is favorable, the method can substantially increase inspection throughput.

  9. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, Richard; Kotter, Dale

    1994-01-01

    An optical voltage reference for providing an alternative to a battery source. The optical reference apparatus provides a temperature stable, high precision, isolated voltage reference through the use of optical isolation techniques to eliminate current and impedance coupling errors. Pulse rate frequency modulation is employed to eliminate errors in the optical transmission link while phase-lock feedback is employed to stabilize the frequency to voltage transfer function.

  10. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, R.; Kotter, D.

    1994-04-26

    An optical voltage reference for providing an alternative to a battery source is described. The optical reference apparatus provides a temperature stable, high precision, isolated voltage reference through the use of optical isolation techniques to eliminate current and impedance coupling errors. Pulse rate frequency modulation is employed to eliminate errors in the optical transmission link while phase-lock feedback is employed to stabilize the frequency to voltage transfer function. 2 figures.