National Library of Energy BETA

Sample records for diodes leds displace

  1. Demonstration Assessment of Light Emitting Diode (LED) Street...

    Energy Savers [EERE]

    Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report This...

  2. Demonstration Assessment of Light-Emitting Diode (LED) Freezer...

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

    Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting This document is a report...

  3. Demonstration Assessment of Light-Emitting Diode (LED) Street...

    Office of Scientific and Technical Information (OSTI)

    Street Lighting Host Site: Lija Loop, Portland, Oregon Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Street Lighting Host Site:...

  4. Demonstration Assessment of Light-Emitting Diode (LED) Accent...

    Office of Scientific and Technical Information (OSTI)

    Accent Lighting at the Field Museum in Chicago, IL Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Accent Lighting at the Field...

  5. Demonstration Assessment of Light-Emitting Diode (LED) Parking...

    Office of Scientific and Technical Information (OSTI)

    Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting at T.J.Maxx in Manchester, NH Phase I A report describing the process and results of...

  6. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting

    SciTech Connect (OSTI)

    None

    2009-11-01

    A U.S. Department of Energy Solid-State Lighting Gateway Report on a Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting in Lija Loop, Portland, Oregon.

  7. Demonstration Assessment of Light-Emitting Diode (LED) Area Lights for a Commercial Garage

    SciTech Connect (OSTI)

    None

    2008-11-01

    This U.S. Department of Energy GATEWAY Demonstration project studied the applicability of light-emitting diode (LED) luminaires for commercial parking garage applications.

  8. Depth of cure and compressive strength of dental composites cured with blue light emitting diodes (LEDs)

    E-Print Network [OSTI]

    Ashworth, Stephen H.

    Depth of cure and compressive strength of dental composites cured with blue light emitting diodes with either a light emitting diode (LED) based light curing unit (LCU) or a conventional halogen LCU do reserved. Keywords: Blue light emitting diodes; Light curing unit; Composites; Irradiance; Spectrum; Depth

  9. Demonstration Assessment of Light-Emitting Diode (LED) Post-Top...

    Office of Scientific and Technical Information (OSTI)

    Central Park in New York City A review of five post-top light-emitting diode (LED) pedestrian luminaires installed in New York City's Central Park for possible replacement to the...

  10. Demonstration Assessment of Light-Emitting Diode (LED) Roadway...

    Office of Scientific and Technical Information (OSTI)

    a three-year evaluation of the LED luminaires in this installation in order to develop new longitudinal field data on LED performance in a challenging, real-world environment....

  11. Demonstration of Light-Emitting Diode (LED) Retrofit Lamps

    SciTech Connect (OSTI)

    Miller, N.

    2011-09-01

    GATEWAY program report on a demonstration of LED retrofit lamps at the Jordan Schnitzer Museum of art in Eugene, OR

  12. TESLA-FEL 2007-03 Application of low cost GaAs LED as neutron

    E-Print Network [OSTI]

    neutrons in unbiased Gallium Arsenide (GaAs) Light Emitting Diodes (LED) resulted in a reduction Keywords: COTS components, Displacement damage, Electron Linear Accelerator, GaAs Light emitting diode (LED) Gallium Arsenide (GaAs) light emitting diode (LED) for the assessment of integrated neutron fluence

  13. Development of substrate-removal-free vertical ultraviolet light-emitting diode (RefV-LED)

    SciTech Connect (OSTI)

    Kurose, N., E-mail: kurose@fc.ritsumei.ac.jp; Aoyagi, Y. [The Research Organization of Science and Technology, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga 525-8577 (Japan)] [The Research Organization of Science and Technology, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga 525-8577 (Japan); Shibano, K.; Araki, T. [Department of Science and Technology, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga 525-8577 (Japan)] [Department of Science and Technology, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga 525-8577 (Japan)

    2014-02-15

    A vertical ultraviolet (UV) light-emitting diode (LED) that does not require substrate removal is developed. Spontaneous via holes are formed in n-AlN layer epitaxially grown on a high conductive n+Si substrate and the injected current flows directly from the p-electrode to high doped n{sup +} Si substrate through p-AlGaN, multi-quantum wells, n-AlGaN and spontaneous via holes in n-AlN. The spontaneous via holes were formed by controlling feeding-sequence of metal-organic gas sources and NH{sub 3} and growth temperature in MOCVD. The via holes make insulating n-AlN to be conductive. We measured the current-voltage, current-light intensity and emission characteristics of this device. It exhibited a built-in voltage of 3.8 V and emission was stated at 350 nm from quantum wells with successive emission centered at 400?nm. This UV LED can be produced, including formation of n and p electrodes, without any resist process.

  14. Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Phase III Continuation

    SciTech Connect (OSTI)

    None

    2008-11-01

    This report summarizes the third phase of an LED street lighting assessment project in Oakland, California, conducted to study the applicability of LED luminaires in a street lighting application.

  15. Demonstration Assessment of Light-Emitting Diode (LED) Retrofit Lamps at the Lobby of the Bonneville Power Administration, Portland, OR

    SciTech Connect (OSTI)

    Miller, Naomi

    2011-07-01

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology in the lobby of the Bonneville Power Administration (BPA) headquarters building in Portland, Oregon. The project involved a simple retrofit of 32 track lights used to illuminate historical black-and-white photos and printed color posters from the 1930s and 1940s. BPA is a federal power marketing agency in the Northwestern United States, and selected this prominent location to demonstrate energy efficient light-emitting diode (LED) retrofit options that not only can reduce the electric bill for their customers but also provide attractive alternatives to conventional products, in this case accent lighting for BPA's historical artwork.

  16. Demonstration Assessment of Light Emitting Diode (LED) Commercial Garage Lights In the Providence Portland Medical Center, Portland, Oregon

    SciTech Connect (OSTI)

    Ton, My K.; Richman, Eric E.; Gilbride, Theresa L.

    2008-11-11

    This U.S. Department of Energy GATEWAY Demonstration project studied the applicability of light-emitting diode (LED) luminaires for commercial parking garage applications. High-pressure sodium (HPS) area luminaires were replaced with new LED area luminaires. The project was supported under the U.S. Department of Energy (DOE) Solid State Lighting Program. Other participants in the demonstration project included Providence Portland Medical Center in Portland, Oregon, the Energy Trust of Oregon, and Lighting Sciences Group (LSG) Inc. Pacific Northwest National Laboratory (PNNL) conducted the measurements and analysis of the results. PNNL manages GATEWAY demonstrations for DOE and represents their perspective in the conduct of the work. Quantitative and qualitative measurements of light and electrical power were taken at the site for both HPS and LED light sources. Economic costs were estimated and garage users’ responses to the new light sources were gauged with a survey. Six LED luminaires were installed in the below-ground parking level A, replacing six existing 150W HPS lamps spread out over two rows of parking spaces. Illuminance measurements were taken at floor level approximately every 4 ft on a 60-ft x 40-ft grid to measure light output of these LED luminaires which were termed the “Version 1” luminaires. PNNL conducted power measurements of the circuit in the garage to which the 6 luminaires were connected and determined that they drew an average of 82 W per lamp. An improved LED luminaire, Version 2, was installed in Level B of the parking garage. Illuminance measurements were not made of this second luminaire on site due to higher traffic conditions, but photometric measurements of this lamp and Version 1 were made in an independent testing laboratory and power usage for Version 2 was also measured. Version 1 was found to produce 3600 lumens and Version 2 was found to produce 4700 lumens of light and to consume 78 Watts. Maximum and minimum light levels were measured for the HPS and LED Version 1 luminaires and projected for the Version 2 luminaires. Maximum light levels were 23.51 foot candles, 20.54 fc, and 26.7 fc respectively and minimum light levels were 1.49 fc, 1.45 fc, and 1.88 fc. These results indicate very similar or even slightly higher light levels produced by the LED lamps, despite the higher lumen output of the HPS lamp. The LED lamps provide higher luminaire efficacy because all of the light is directed down and out. None of it is “lost” in the fixture. Also the HPS luminaire had poorly designed optics and a plastic covering that tended to get dirty and cracked, further decreasing the realized light output.[is this an accurate way to say this?] Consumer perceptions of the Version 2 LED were collected via a written survey form given to maintenance and security personnel. More than half felt the LED luminaires provided more light than the HPS lamps and a majority expressed a preference for the new lamps when viewing the relamped area through a security camera. Respondents commented that the LED luminaires were less glary, created less shadows, had a positive impact on visibility, and improved the overall appearance of the area. PNNL conducted an economic analysis and found that the Version 1 lamp produced annual energy savings of 955 kWh and energy cost savings of $76.39 per lamp at electricity rates of 6.5 cents per kWh and $105.03 at 11 cents per kWh. PNNL found that the Version 2 lamp produced annual energy savings of 991 kWh and energy cost savings of $79.26 per lamp at electricity rates of 6.5 cents per kWh and $108.98 at 11 cents per kWh. PNNL also calculated simple payback and found that Version 1 showed paybacks of 5.4 yrs at 6.5c/kWh and 4.1 yrs at 11c/kWh while Version 2 showed paybacks of 5.2 yrs at 6.5c/kWh and 3.9 yrs at 11c/kWh.

  17. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting, I-35W Bridge, Minneapolis, Minnesota, Phase II Report

    SciTech Connect (OSTI)

    Kinzey, B. R.; Davis, R. G.

    2014-09-30

    On the I-35W Bridge in Minneapolis, Minnesota, the GATEWAY program conducted a two-phase demonstration of LED roadway lighting on the main span, which is one of the country's oldest continuously operated exterior LED lighting installations. The Phase II report documents longer-term performance of the LED lighting system that was installed in 2008, and is the first report on the longer-term performance of LED lighting in the field.

  18. LED Frequently Asked Questions

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

    term for semiconductors used to convert electricity into light. LED - light-emitting diode. CCT - correlated color temperature; a measure of the color appearance of a white...

  19. LED Lighting Basics

    Broader source: Energy.gov [DOE]

    Light-Emitting diodes (LEDs) efficiently produce light in a fundamentally different way than any legacy or traditional source of light.

  20. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting, I-35W Bridge, Minneapolis, Minnesota, Phase I Report

    SciTech Connect (OSTI)

    None

    2009-08-01

    On the I-35W Bridge in Minneapolis, Minnesota, the GATEWAY program conducted a two-phase demonstration of LED roadway lighting on the main span, which is one of the country's oldest continuously operated exterior LED lighting installations. The Phase I report provides an overview of initial project results including lighting performance, economic performance, and potential energy savings.

  1. Demonstration Assessment of Light Emitting Diode (LED) Residential Downlights and Undercabinet Lights in the Lane County Tour of Homes, Eugene, Oregon

    SciTech Connect (OSTI)

    Ton, My K.; Richman, Eric E.; Gilbride, Theresa L.

    2008-11-10

    In August 2008 the Pacific Northwest National Laboratory (PNNL) conducted a light emitting diode (LED) residential lighting demonstration project for the U.S. Department of Energy (DOE), Office of Building Technologies, as part of DOE’s Solid State Lighting (SSL) Technology Demonstration Gateway Program. Two lighting technologies, an LED replacement for downlight lamps (bulbs) and an LED undercabinet lighting fixture, were tested in the demonstration which was conducted in two homes built for the 2008 Tour of Homes in Eugene, Oregon. The homes were built by the Lane County Home Builders Association (HBA), and Future B Homes. The Energy Trust of Oregon (ETO) also participated in the demonstration project. The LED downlight product, the LR6, made by Cree LED Lighting Solutions acts as a screw-in replacement for incandescent and halogen bulbs in recessed can downlights. The second product tested is Phillips/Color Kinetics’ eW® Profile Powercore undercabinet fixture designed to mount under kitchen cabinets to illuminate the countertop and backsplash surfaces. Quantitative and qualitative measurements of light performance and electrical power usage were taken at each site before and after initially installed halogen and incandescent lamps were replaced with the LED products. Energy savings and simple paybacks were also calculated and builders who toured the homes were surveyed for their responses to the LED products. The LED downlight product drew 12 Watts of power, cutting energy use by 82% compared to the 65W incandescent lamp and by 84% compared to the 75W halogen lamp. The LED undercabinet fixture drew 10 watts, cutting energy use by 83% to 90% compared to the halogen product, which was tested at two power settings: a low power 60W setting and a high power 105W setting. The LED downlight consistently provided more light than the halogen and incandescent lamps in horizontal measurements at counter height and floor level. It also outperformed in vertical illuminance measurements taken on the walls, indicating better lateral dispersion of the light. The undercabinet fixture’s light output was midway between the low and high power halogen undercabinet fixture light outputs (35.8 foot candle versus 13.4 fc and 53.4 fc) but it produced a more uniform light (max/min ratio of 7.0 versus 10.8). The color correlated temperature (CCT, the blue or yellowness) of the LED light correlated well with the halogen and incandescent lights (2675 K vs 2700 K). The color rendering of the LED downlight also correlated well at 92 CRI compared to 100 CRI for the halogen and incandescent lamps. The LED undercabinet fixture had measures of 2880 K CCT and 71 CRI compared to the 2700 K and 100 CRI scores for the halogen undercabinet fixture. Builders who toured the homes were surveyed; they gave the LED downlight high marks for brightness, said the undercabinet improved shadows and glare and said both products improved overall visibility, home appearance, and home value. Paybacks on the LED downlight ranged from 7.6 years (assuming electricity cost of 11 c/kWh) to 13.5 years (at 5C/kWh). Paybacks on the LED undercabinet fixture in a new home ranged from 4.4 years (11c/kWh electricity) to 7.6 years (5c/kWh) based on product costs of $95 per LED downlight and $140 per LED undercabinet fixture at 3 hrs per day of usage for the downlight and 2 hrs per day for the undercabinet lighting.

  2. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting on Residential and Commercial Streets in Palo Alto, CA

    SciTech Connect (OSTI)

    Myer, Michael; Kinzey, Bruce R.; Tam, Christine

    2010-06-24

    This report is part of a GATEWAY demonstration that replaced existing HPS streetlights with two different types of LED products and one induction product. Energy savings ranged from 6% to 44%.

  3. Potential Environmental Impacts from the Metals in Incandescent, Compact Fluorescent Lamp (CFL), and Light-Emitting Diode (LED)

    E-Print Network [OSTI]

    Short, Daniel

    Potential Environmental Impacts from the Metals in Incandescent, Compact Fluorescent Lamp (CFL, previous studies have investigated various environmental impacts from incandescent, CFL, and LED bulbs. There is uncertainty about the potential environmental impacts of these components and whether special provisions must

  4. Demonstration Assessment of Light Emitting Diode (LED) Walkway Lighting at the Federal Aviation Administration William J. Hughes Technical Center, in Atlantic City, New Jersey

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Myer, Michael

    2008-03-18

    This report documents the results of a collaborative project to demonstrate a solid state lighting (SSL) general illumination product in an outdoor area walkway application. In the project, six light-emitting diode (LED) luminaires were installed to replace six existing high pressure sodium (HPS) luminaires mounted on 14-foot poles on a set of exterior walkways and stairs at the Federal Aviation Administration (FAA) William J. Hughes Technical Center in Atlantic City, New Jersey, during December, 2007. The effort was a U.S. Department of Energy (DOE) SSL Technology Gateway Demonstration that involved a collaborative teaming agreement between DOE, FAA and Ruud Lighting (and their wholly owned division, Beta LED). Pre- and post-installation power and illumination measurements were taken and used in calculations of energy savings and related economic payback, while personnel impacted by the new lights were provided questionnaires to gauge their perceptions and feedback. The SSL product demonstrated energy savings of over 25% while maintaining illuminance levels and improving illuminance uniformity. PNNL's economic analysis yielded a variety of potential payback results depending on the assumptions used. In the best case, replacing HPS with the LED luminaire can yield a payback as low as 3 years. The new lamps were quite popular with the affected personnel, who gave the lighting an average score of 4.46 out of 5 for improvement.

  5. LED lamp

    DOE Patents [OSTI]

    Galvez, Miguel; Grossman, Kenneth; Betts, David

    2013-11-12

    There is herein described a lamp for providing white light comprising a plurality of light sources positioned on a substrate. Each of said light sources comprises a blue light emitting diode (LED) and a dome that substantially covers said LED. A first portion of said blue light from said LEDs is transmitted through said domes and a second portion of said blue light is converted into a red light by a first phosphor contained in said domes. A cover is disposed over all of said light sources that transmits at least a portion of said red and blue light emitted by said light sources. The cover contains a second phosphor that emits a yellow light in response to said blue light. The red, blue and yellow light combining to form the white light and the white light having a color rendering index (CRI) of at least about 80.

  6. GATEWAY Demonstrations: LED Street Lighting

    SciTech Connect (OSTI)

    Cook, Tyson; Shackelford, Jordan; Pang, Terrance Pang

    2008-12-01

    This report summarizes an assessment project conducted to study the performance of light emitting diode (LED) luminaires in a street lighting application in San Francisco, CA.

  7. LED Update

    SciTech Connect (OSTI)

    Johnson, Mark L.; Gordon, Kelly L.

    2006-09-01

    This article, which will appear in RESIDENTIAL LIGHTING MAGAZINE, interviews PNNL's Kelly Gordon and presents the interview in question and answer format. The topic is a light emitting diode (LED) lighting also known as solid state lighting. Solid state lighting will be a new category in an energy efficient lighting fixture design competition called Lighting for Tomorrow sponsored by the US Department of Energy Emerging Technologies Office, the American Institute for Lighting, and the Consortium for Energy Efficiency. LED technology has been around since the ’60s, but it has been used mostly for indicator lights on electronics equipment. The big breakthrough was the development in the 1990s of blue LEDs which can be combined with the red and green LEDs that already existed to make white light. LEDs produce 25 to 40 lumens of light per watt of energy used, almost as much as a CFL (50 lumens per watt) and much more efficient than incandescent sources, which are around 15 lumens per watt. They are much longer lived and practical in harsh environments unsuitable for incandescent lighting. They are ready for niche applications now, like under-counter lighting and may be practical for additional applications as technological challenges are worked out and the technology is advancing in leaps and bounds.

  8. LED ProspectsLED Prospects photometric units

    E-Print Network [OSTI]

    Pulfrey, David L.

    -life incandescent with LED. · 10 light fixtures/home, lights on for 6h/day, 333 days/yr. · Electricity 0.12 $/kWh. W Illuminated by: (a) high-CRI source (b) low-CRI source EFS #12;6 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;7 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;8 http://www.ecse.rpi.edu/~schubert/Light

  9. COMMUNIQU DE PRESSE NATIONAL I PARIS I 31 JANVIER 2014 La course la miniaturisation des diodes lectroluminescentes (DEL, en anglais : Light-

    E-Print Network [OSTI]

    Arleo, Angelo

    diodes électroluminescentes (DEL, en anglais : Light- Emitting Diode, LED) vient sans doute de franchir l

  10. Toward ZnO Light Emitting Diode

    E-Print Network [OSTI]

    Liu, Jianlin

    2008-01-01

    applications such as light emitting diodes (LEDs) and laser009 "Toward ZnO Light Emitting Diode" Jianlin Liu July 2008Title: “Toward ZnO Light Emitting Diode” Sponsor: UC Energy

  11. Demonstration Assessment of Light-Emitting Diode (LED) Retrofit Lamps at an Exhibit of 19th Century Photography at the Getty Museum

    SciTech Connect (OSTI)

    Miller, N. J.; Druzik, J. R.

    2012-03-01

    GATEWAY program report on a demonstration of LED retrofit lamps at the J. Paul Getty Museum in Malibu, CA.

  12. An Brief Overview Of Using LEDs In Lab

    E-Print Network [OSTI]

    Baas, Bevan

    (~zero current) ­ Forward biased (high current flow) Regular (Non-Light-Emitting) Diode Operation 0 V 5 V Current ~0 high (too high); typically ~2-3V 5 V 0 V I anode cathode #12;3 Light-Emitting Diodes · A Light-Emitting Diode (LED) is a special type of diode that emits photons (light) when current flows through the diode

  13. LED Lighting | Department of Energy

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

    focusing light in ways that are useful in homes and commercial settings. The light-emitting diode (LED) is one of today's most energy-efficient and rapidly-developing lighting...

  14. LED Lighting | Department of Energy

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

    are directional, focusing light in ways that are useful in homes and commercial settings. The light-emitting diode (LED) is one of today's most energy-efficient and...

  15. LIGHT EMITTING DIODE CHARACTERISTICS (SAMPLE LAB WRITEUP)

    E-Print Network [OSTI]

    McNeill, John A.

    1 LIGHT EMITTING DIODE CHARACTERISTICS (SAMPLE LAB WRITEUP) John A. McNeill ECE Box 000 January 19, 1997 ABSTRACT This lab investigates the V-I characteristic of a light-emitting diode (LED

  16. Energy Savings Estimates of Light Emitting Diodes

    Broader source: Energy.gov [DOE]

    This report is an analysis of niche markets and applications for light emitting diodes (LEDs), undertaken on behalf of the U.S. Department of Energy

  17. CALiPER Benchmark Report: Performance of Halogen Incandescent MR16 Lamps and LED Replacement

    SciTech Connect (OSTI)

    None

    2008-11-01

    This benchmark report addresses the halogen MR16 lamp and its commercially available light-emitting diode (LED) replacements.

  18. Color Maintenance of LEDs in Laboratory and Field Applications...

    Office of Scientific and Technical Information (OSTI)

    Royer, Michael P.; Tuttle, Ralph; Rosenfeld, Scott M.; Miller, Naomi J. Light-emitting diode (LED), color shift, color stability, color maintenance, warranty Light-emitting...

  19. Application Assessment of Bi-Level LED Parking Lot Lighting

    SciTech Connect (OSTI)

    None

    2009-02-01

    This report summarizes an assessment project conducted to evaluate light-emitting diode (LED) luminaires with bi-level operation in an outdoor parking lot application.

  20. Purchasing Energy-Efficient Commercial and Industrial LED Luminaires

    Broader source: Energy.gov [DOE]

    The Federal Energy Management Program (FEMP) provides acquisition guidance for commercial and industrial light emitting diode (LED) luminaires, a product category covered by FEMP efficiency...

  1. Demonstration Assessment of LED Freezer Case Lighting

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

    Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting Host Site: Albertsons Grocery, Eugene, Oregon Final Report prepared in support of the U.S. DOE Solid...

  2. A merged two-stage converter for LED lighting applications

    E-Print Network [OSTI]

    Ranson, John (John David)

    2012-01-01

    Light Emitting Diodes (LEDs) are a very promising technology for developing more efficient lighting. For high-efficiency applications, a switching current regulator is necessary to control the power drawn by an LED string. ...

  3. Seeing the Light: LED Under-Cabinet and Recessed Downlights ...

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

    operating at their optimum energy efficiency. I'm definitely drawn to the light-emitting diode (LED) under-cabinet and recessed downlights-just two of the many LED products....

  4. LEDs: The Future of Lighting is Here | Department of Energy

    Energy Savers [EERE]

    and the common household light bulb have in common? If your answer is that light emitting diode (LED) technology can power all these things, then you're pretty bright. LEDs...

  5. Today LED Holiday Lights, Tomorrow the World?

    SciTech Connect (OSTI)

    Gordon, Kelly L.

    2004-12-20

    This article for The APEM Advantage, the quarterly newsletter of the Association of Professional Energy Managers (APEM) describes the recent increase in the popularity of light emitting diode (LED) lighting and compares LED light output with that of incandescent and compact fluorescent lighting.

  6. LED Light Fixture Project FC1 Director's Conference Room: Life Cycle Cost and Break-even Analysis

    E-Print Network [OSTI]

    Johnston, Daniel

    . A light-emitting diode (LED) is a solid-state lighting source that switches on instantly, is readily

  7. Flexible LEDs bring light to fingertips Oct 19, 2010

    E-Print Network [OSTI]

    Rogers, John A.

    Flexible LEDs bring light to fingertips Oct 19, 2010 Glowing gloves Light-emitting diodes ­ or LEDs counterparts, known as holes, are driven into the well where they combine to emit light. LEDs are normally made that is populated with red LEDs. Stitches incorporating these tiny light emitters have been inserted

  8. LED ProspectsLED Prospects photometric units

    E-Print Network [OSTI]

    Pulfrey, David L.

    Illuminated by: (a) high-CRI source (b) low-CRI source EFS #12;6 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;7 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;8 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;9 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;10 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes

  9. LEDs_2LEDs_2 radiative recombination efficiency

    E-Print Network [OSTI]

    Pulfrey, David L.

    (E) lead to a peak in the light intensity. E.F. Schubert, Light-Emitting Diodes, CUP, 2006 [EFS] #12

  10. Demonstration of a semipolar (10(1)over-bar(3)over-bar) InGaN/GaN green light emitting diode

    E-Print Network [OSTI]

    2005-01-01

    InGaN / GaN green light emitting diode R. Sharma, a? P. M.green ??525 nm? light emitting diode ?LED?. The fabricated

  11. Thermal pumping of light-emitting diodes

    E-Print Network [OSTI]

    Gray, Dodd (Dodd J.)

    2011-01-01

    The work presented here is a study of thermally enhanced injection in light-emitting diodes (LEDs). This effect, which we refer to as "thermal pumping", results from Peltier energy exchange from the lattice to charge ...

  12. White light emitting diode as liquid crystal display backlight

    E-Print Network [OSTI]

    Soon, Chian Myau

    2007-01-01

    The discovery of high brightness (white) light emitting diode (LED) is considered as a real threat to the current lighting industry in various applications. One of the most promising sectors would be using white LED to ...

  13. CALiPER Benchmark Report: Performance of Incandescent A Type and Decorative Lamps and LED Replacements

    SciTech Connect (OSTI)

    None

    2008-11-01

    This benchmark report addresses common omnidirectional incandescent lamps - A-type and small decorative, candelabra-type lamps - and their commercially available light-emitting diode (LED) replacements.

  14. New Family of Tiny Crystals Glow Bright in LED Lights | Advanced...

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

    crystals that glow different colors may be the missing ingredient for white light-emitting diode (LED) lighting that illuminates homes and offices as effectively as natural...

  15. Abbreviated MOVPE nucleation of III-nitride light-emitting diodes on nano-patterned sapphire

    E-Print Network [OSTI]

    Gilchrist, James F.

    -patterned AGOG sapphire demonstrated a 24% enhancement of output power enhancement over that of LEDs grown) light-emitting diodes (LEDs) on both templates were compared. The InGaN QWs LEDs grown on the nano- emitting diodes (LEDs) in solid state lighting applications [1 À11]. In conventional metalorganic vapor

  16. Energy - LEDs to light UT arena | ornl.gov

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

    to 85 percent more efficient than conventional arena metal halide lights. The light-emitting diode fixtures developed by Oak Ridge-based LED North America incorporate an Oak...

  17. EECBG Success Story: Solar LED Light Pilot Project Illuminates...

    Broader source: Energy.gov (indexed) [DOE]

    courtesy of Lionel Green, Sand Mountain Reporter. A strip of new solar-powered light emitting-diode (LED) streetlights in Boaz, Alabama were installed with grant funds from the...

  18. LED Traffic Light as a Communications Device Grantham Pang, Thomas Kwan, Chi-Ho Chan, Hugh Liu.

    E-Print Network [OSTI]

    Pang, Grantham

    :http://www.eee.hku.hk/~gpang Abstract The visible light from an LED (light emitting diode) traffic light can be modulated and encoded on the description of an audio information system made up of high brightness, visible light emitting diodes (LEDs messages 1. Introduction Recently, high intensity light emitting diodes for traffic signals are available

  19. A description and evaluation of light-emitting diode displays for generation of visual stimuli*

    E-Print Network [OSTI]

    Massaro, Dominic

    A description and evaluation of light-emitting diode displays for generation of visual stimuli 53706 A description of the design and function of light-emitting diode (LED) display modules is given (Time, April 1972). Light-emitting diodes (L~Ds) are examples of these spin-offs, LED display devices

  20. spectroscopic techniques A Multi-Source Portable Light Emitting Diode Spectrofluorometer

    E-Print Network [OSTI]

    spectroscopic techniques A Multi-Source Portable Light Emitting Diode Spectrofluorometer SAFWAN only 1.5 kg that uses multiple light emitting diodes (LEDs) as excitation sources was developed emitting diodes; LEDs; Animal forage; Excitation-emission matrices; EEM. INTRODUCTION Movement of chemical

  1. Color-tunable light emitting diodes based on quantum dot suspension

    E-Print Network [OSTI]

    Wu, Shin-Tson

    Color-tunable light emitting diodes based on quantum dot suspension Zhenyue Luo, Haiwei Chen, Yifan March 2015 We propose a color-tunable light emitting diode (LED) consisting of a blue LED as the light, rendering and metamerism; (230.3670) Light-emitting diodes. http://dx.doi.org/10.1364/AO.54.002845 1

  2. A strategy for the use of light emitting diodes by autonomous underwater vehicles

    E-Print Network [OSTI]

    Curran, Joseph R. (Joseph Robinson)

    2004-01-01

    Light Emitting Diode (LED) technology has advanced dramatically in a few short years. An expensive and difficult to manufacture LED array containing nearly 100 individual LEDs and measuring at least 5 cm² can now be replaced ...

  3. Ruofan Wu, Hieu Pham Trung Nguyen and Zetian Mi INTRODUCTION TO LEDs

    E-Print Network [OSTI]

    Barthelat, Francois

    -in-a-Wire Light Emitting Diodes and Prevention Method Nano-electronic Devices and Materials, Electrical Computer., Efficiency droop in nitride-based light-emitting diodes. Physica Status Solidi a-Applications and Materials history. Nature Photonics 2007, 1 (4), 189-192. [4] Holonyak, N., Is the light emitting diode (LED

  4. Coupled optical and electronic simulations of electrically pumped photonic-crystal-based LEDs

    E-Print Network [OSTI]

    Dutton, Robert W.

    to investigate design tradeoffs in electrically pumped photonic crystal light emitting diodes. A finite. Keywords: Photonic crystal light emitting diode, electrically pumped device 1. INTRODUCTION Recently optoelectronic devices, such as light emitting diodes (LEDs) and lasers. It has been suggested that a thin slab

  5. Quantum Dot Light Emitting Diode

    SciTech Connect (OSTI)

    Keith Kahen

    2008-07-31

    The project objective is to create low cost coatable inorganic light emitting diodes, composed of quantum dot emitters and inorganic nanoparticles, which have the potential for efficiencies equivalent to that of LEDs and OLEDs and lifetime, brightness, and environmental stability between that of LEDs and OLEDs. At the end of the project the Recipient shall gain an understanding of the device physics and properties of Quantum-Dot LEDs (QD-LEDs), have reliable and accurate nanocrystal synthesis routines, and have formed green-yellow emitting QD-LEDs with a device efficiency greater than 3 lumens/W, a brightness greater than 400 cd/m2, and a device operational lifetime of more than 1000 hours. Thus the aim of the project is to break the current cost-efficiency paradigm by creating novel low cost inorganic LEDs composed of inorganic nanoparticles.

  6. Quantum Dot Light Emitting Diode

    SciTech Connect (OSTI)

    Kahen, Keith

    2008-07-31

    The project objective is to create low cost coatable inorganic light emitting diodes, composed of quantum dot emitters and inorganic nanoparticles, which have the potential for efficiencies equivalent to that of LEDs and OLEDs and lifetime, brightness, and environmental stability between that of LEDs and OLEDs. At the end of the project the Recipient shall gain an understanding of the device physics and properties of Quantum-Dot LEDs (QD-LEDs), have reliable and accurate nanocrystal synthesis routines, and have formed green-yellow emitting QD-LEDs with a device efficiency greater than 3 lumens/W, a brightness greater than 400 cd/m{sup 2}, and a device operational lifetime of more than 1000 hours. Thus the aim of the project is to break the current cost-efficiency paradigm by creating novel low cost inorganic LEDs composed of inorganic nanoparticles.

  7. An Investigation into the Perception of Color under LED White Composite Spectra with Modulated Color Rendering

    E-Print Network [OSTI]

    O'Reilly, Una-May

    emitting diodes, LEDs. We examined seven LED white composite spectra with different color rendering of a pilot study that evaluates the perceptual impact of modulation of color rendering using multi-chip light

  8. Multispectral imaging of the ocular fundus using light emitting diode illumination

    E-Print Network [OSTI]

    Claridge, Ela

    Multispectral imaging of the ocular fundus using light emitting diode illumination N. L. Everdell,1 on light emitting diode LED illumination that produces multispectral optical images of the human ocular

  9. Multicolor, High Efficiency, Nanotextured LEDs

    SciTech Connect (OSTI)

    Jung Han; Arto Nurmikko

    2011-09-30

    We report on research results in this project which synergize advanced material science approaches with fundamental optical physics concepts pertaining to light-matter interaction, with the goal of solving seminal problems for the development of very high performance light emitting diodes (LEDs) in the blue and green for Solid State Lighting applications. Accomplishments in the duration of the contract period include (i) heteroepitaxy of nitrogen-polar LEDs on sapphire, (ii) heteroepitaxy of semipolar (11{bar 2}2) green LEDs on sapphire, (iii) synthesis of quantum-dot loaded nanoporous GaN that emits white light without phosphor conversion, (iv) demonstration of the highest quality semipolar (11{bar 2}2) GaN on sapphire using orientation-controlled epitaxy, (v) synthesis of nanoscale GaN and InGaN medium, and (vi) development of a novel liftoff process for manufacturing GaN thin-film vertical LEDs. The body of results is presented in this report shows how a solid foundation has been laid, with several noticeable accomplishments, for innovative research, consistent with the stated milestones.

  10. LEDs_3LEDs_3 current efficiency

    E-Print Network [OSTI]

    Pulfrey, David L.

    1 LEDs_3LEDs_3 LECTURE 12 · current efficiency · extraction efficiency · wall-plug efficiency efficiencySec. 8.4 How much power gets out for GaAs? Adapted from Schubert, loc. cit. #12;5 Design to improve extraction efficiencyDesign to improve extraction efficiencySec. 8.4 What are the features of this LED from

  11. Optical Wireless based on High Brightness Visible LEDs Grantham Pang, Thomas Kwan, Hugh Liu, Chi-Ho Chan

    E-Print Network [OSTI]

    Pang, Grantham

    tolerance to humidity, low power consumption and minimal heat generation. Light-emitting diodes (LEDsOptical Wireless based on High Brightness Visible LEDs Grantham Pang, Thomas Kwan, Hugh Liu, Chi use of lighting or signaling devices constructed by light-emitting diodes (LEDs). The idea

  12. High Performance Green LEDs by Homoepitaxial

    SciTech Connect (OSTI)

    Wetzel, Christian; Schubert, E Fred

    2009-11-22

    This work's objective was the development of processes to double or triple the light output power from green and deep green (525 - 555 nm) AlGaInN light emitting diode (LED) dies within 3 years in reference to the Lumileds Luxeon II. The project paid particular effort to all aspects of the internal generation efficiency of light. LEDs in this spectral region show the highest potential for significant performance boosts and enable the realization of phosphor-free white LEDs comprised by red-green-blue LED modules. Such modules will perform at and outperform the efficacy target projections for white-light LED systems in the Department of Energy's accelerated roadmap of the SSL initiative.

  13. A NEW LED-LED PORTABLE CO2 GAS SENSOR BASED ON AN INTERCHANGEABLE MEMBRANE SYSTEM FOR INDUSTRIAL APPLICATIONS

    E-Print Network [OSTI]

    Lee, Hyowon

    to oxygen scavenging [5]. High CO2 levels (10- 80 %) are desirable for foods such as meat and poultryA NEW LED-LED PORTABLE CO2 GAS SENSOR BASED ON AN INTERCHANGEABLE MEMBRANE SYSTEM FOR INDUSTRIAL APPLICATIONS Abstract A new system for CO2 measurement (0-100%) by based on a paired emitter-detector diode

  14. LED Market Intelligence Report

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

    around dimming capabilities. 16 LED Market Intelligence Report Home Depot Walmart Cree Philips TCP GE LSG Osram Feit Costco Lowe's Retail, Regulations, and LEDs Like...

  15. Energy Savings Estimates of Light Emitting Diodes in Niche Lighting Applications

    SciTech Connect (OSTI)

    none,

    2011-01-01

    This report is an analysis of niche markets and applications for light-emitting diodes (LEDs), undertaken on behalf of the U.S. Department of Energy.

  16. Energy Savings Estimates of Light Emitting Diodes in Niche Lighting Applications

    SciTech Connect (OSTI)

    None

    2008-10-01

    This report is an analysis of niche markets and applications for light-emitting diodes (LEDs), undertaken on behalf of the U.S. Department of Energy.

  17. Pousset, Obein, Razet, LED lighting quality with CQS samples CIE 2010 : Lighting Quality and Energy Efficiency, 14-17 March 2010, Vienna, Austria 1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A psychophysical experiment developed to evaluate light quality of Light Emitting Diodes (LEDs) is described. Keywords: Light Emitting Diode, quality of light, Color Rendering Index, Color Quality Scale, visual

  18. Wide band-gap nanowires for light emitting diodes

    E-Print Network [OSTI]

    Chesin, Jordan (Jordan Paul)

    2015-01-01

    Wide band-gap nanowires composed of GaN and ZnO are promising materials for unique designs and potential efficiency improvement of light emitting diodes (LEDs) for solid state lighting. The large surface-to-volume ratio ...

  19. Thermo-electrically pumped semiconductor light emitting diodes

    E-Print Network [OSTI]

    Santhanam, Parthiban

    2014-01-01

    Thermo-electric heat exchange in semiconductor light emitting diodes (LEDs) allows these devices to emit optical power in excess of the electrical power used to drive them, with the remaining power drawn from ambient heat. ...

  20. Space charge spectroscopy of integrated quantum well infrared photodetectorlight emitting diode

    E-Print Network [OSTI]

    Perera, A. G. Unil

    Space charge spectroscopy of integrated quantum well infrared photodetector±light emitting diode M ± light emitting diode (QWIP-LED). Quasistatic capacitance±voltage (C±V ) characteristics under reverse.V. All rights reserved. Keywords: Quantum-well infrared photodetector; Light-emitting diode; Space charge

  1. Displacer for Stirling engine

    SciTech Connect (OSTI)

    Brown, A. T.

    1985-12-24

    In a Stirling engine and the like, a displacer piston having a plurality of internal baffles and insulation so as to prevent undesired heat transfer across the displacer piston.

  2. Energy Efficiency of LEDs

    Broader source: Energy.gov [DOE]

    This fact sheet discusses the current state of the LED market and discusses package efficacy, luminaire efficacy, and application efficacy.

  3. Broadband light-emitting diode

    DOE Patents [OSTI]

    Fritz, I.J.; Klem, J.F.; Hafich, M.J.

    1998-07-14

    A broadband light-emitting diode is disclosed. The broadband light-emitting diode (LED) comprises a plurality of III-V compound semiconductor layers grown on a semiconductor substrate, with the semiconductor layers including a pair of cladding layers sandwiched about a strained-quantum-well active region having a plurality of different energy bandgaps for generating light in a wavelength range of about 1.3--2 {micro}m. In one embodiment of the present invention, the active region may comprise a first-grown quantum-well layer and a last-grown quantum-well layer that are oppositely strained; whereas in another embodiment of the invention, the active region is formed from a short-period superlattice structure (i.e. a pseudo alloy) comprising alternating thin layers of InGaAs and InGaAlAs. The use a short-period superlattice structure for the active region allows different layers within the active region to be simply and accurately grown by repetitively opening and closing one or more shutters in an MBE growth apparatus to repetitively switch between different growth states therein. The broadband LED may be formed as either a surface-emitting LED or as an edge-emitting LED for use in applications such as chemical sensing, fiber optic gyroscopes, wavelength-divisionmultiplexed (WDM) fiber-optic data links, and WDM fiber-optic sensor networks for automobiles and aircraft. 10 figs.

  4. Broadband light-emitting diode

    DOE Patents [OSTI]

    Fritz, Ian J. (Albuquerque, NM); Klem, John F. (Sandia Park, NM); Hafich, Michael J. (Albuquerque, NM)

    1998-01-01

    A broadband light-emitting diode. The broadband light-emitting diode (LED) comprises a plurality of III-V compound semiconductor layers grown on a semiconductor substrate, with the semiconductor layers including a pair of cladding layers sandwiched about a strained-quantum-well active region having a plurality of different energy bandgaps for generating light in a wavelength range of about 1.3-2 .mu.m. In one embodiment of the present invention, the active region may comprise a first-grown quantum-well layer and a last-grown quantum-well layer that are oppositely strained; whereas in another embodiment of the invention, the active region is formed from a short-period superlattice structure (i.e. a pseudo alloy) comprising alternating thin layers of InGaAs and InGaAlAs. The use a short-period superlattice structure for the active region allows different layers within the active region to be simply and accurately grown by repetitively opening and closing one or more shutters in an MBE growth apparatus to repetitively switch between different growth states therein. The broadband LED may be formed as either a surface-emitting LED or as an edge-emitting LED for use in applications such as chemical sensing, fiber optic gyroscopes, wavelength-division-multiplexed (WDM) fiber-optic data links, and WDM fiber-optic sensor networks for automobiles and aircraft.

  5. Demonstration Assessment of Light-Emitting Diode (LED) Parking...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; COMMERCIAL BUILDINGS; CONSTRUCTION; DEMONSTRATION PROGRAMS;...

  6. Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i n c i pStateDOEAnalysis,DepartmentAbove onDepartment of

  7. Demonstration Assessment of Light Emitting Diode (LED) Street Lighting,

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum Based| Department8, 20153Daniel BoffDepartmentbegins on K-25's NorthPeerFinal

  8. Conference 5739, SPIE International Symposium Integrated Optoelectronic Devices, 22-27 Jan 2005, San Jose, CA Development of high power green light emitting diode dies in

    E-Print Network [OSTI]

    Wetzel, Christian M.

    , San Jose, CA Development of high power green light emitting diode dies in piezoelectric Ga in green light emitting diodes is one of the big challenges towards all-solid- state lighting. The prime,3], and commercialization [4,5] of high brightness light emitting diodes LEDs has led to a 1.82 Billion-$/year world market

  9. ZnO:Sb/ZnO:Ga Light Emitting Diode on c-Plane Sapphire by Molecular Beam Epitaxy Zheng Yang, Sheng Chu, Winnie V. Chen1

    E-Print Network [OSTI]

    Yang, Zheng

    ZnO:Sb/ZnO:Ga Light Emitting Diode on c-Plane Sapphire by Molecular Beam Epitaxy Zheng Yang, Sheng substrates using plasma-assisted molecular-beam epitaxy. Mesa geometry light emitting diodes (LEDs) were demonstrated in recent years, such as photodetectors,8,9) light-emitting diodes (LEDs),10­13) and random lasing

  10. Microcavity enhanced vertical-cavity light-emitting diodes U. Keller, G. R. Jacobovitz-Veselka, J. E. Cunningham, W. Y. Jan, B. Tell,

    E-Print Network [OSTI]

    Keller, Ursula

    Microcavity enhanced vertical-cavity light-emitting diodes U. Keller, G. R. Jacobovitz-Veselka, J-cavity light-emitting diode (LED) by continuously changing the microcavity resonance with respect for optical interconnects seems to be the light emitting diode (LED), or better yet, the microcavity en

  11. LED Lighting Retrofit 

    E-Print Network [OSTI]

    Shaw-Meadow, N.

    2011-01-01

    kWh is the one that never gets used? ?Dedicated to making environmentally responsible products? Ringdale Introduction LED Roadway Lighting Better Light, Fewer Watts. Period. Nathan Shaw-Meadow LED Lighting Specialist Ringdale ActiveLED ESL.../exponential efficiency growth often deters investment today 7 Challenges to Implementation ESL-KT-11-11-57 CATEE 2011, Dallas, Texas, Nov. 7 ? 9, 2011 ? Municipal Street Light Case Study 8 ? Replaced 400W High Pressure Sodium fixtures with 52W Active...

  12. LED Market Adoption

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT PDFLEDLED MR16LED

  13. General Service LED Lamps

    Broader source: Energy.gov [DOE]

    A U.S. DOE SSL technology fact sheet that compares general service LED light bulbs with incandescent and CFL bulbs.

  14. Psychophysical evaluations of modulated color rendering for energy performance of LED-based architectural lighting

    E-Print Network [OSTI]

    Thompson, Maria do Rosário

    2007-01-01

    This thesis is focused on the visual perception evaluation of colors within an environment of a highly automated lighting control strategy. Digitally controlled lighting systems equipped with light emitting diodes, LEDs, ...

  15. Deposition of colloidal quantum dots by microcontact printing for LED display technology

    E-Print Network [OSTI]

    Kim, LeeAnn

    2006-01-01

    This thesis demonstrates a new deposition method of colloidal quantum dots within a quantum dot organic light-emitting diode (QD-LED). A monolayer of quantum dots is microcontact printed as small as 20 ,Lm lines as well ...

  16. Precision displacement reference system

    DOE Patents [OSTI]

    Bieg, Lothar F. (Albuquerque, NM); Dubois, Robert R. (Albuquerque, NM); Strother, Jerry D. (Edgewood, NM)

    2000-02-22

    A precision displacement reference system is described, which enables real time accountability over the applied displacement feedback system to precision machine tools, positioning mechanisms, motion devices, and related operations. As independent measurements of tool location is taken by a displacement feedback system, a rotating reference disk compares feedback counts with performed motion. These measurements are compared to characterize and analyze real time mechanical and control performance during operation.

  17. Nanoscale LEDs DOI: 10.1002/smll.200600628

    E-Print Network [OSTI]

    Odom, Teri W.

    of macroscale organic light-emitting diodes (OLEDs) for full-color dis- plays have created interestNanoscale LEDs DOI: 10.1002/smll.200600628 Addressable, Large-Area Nanoscale Organic Light in generating OLEDs at the nanoscale.[1,2] Reducing the size of an OLED can produce higher device densities per

  18. Photovoltaic-module bypass-diode encapsulation. Annual report

    SciTech Connect (OSTI)

    Not Available

    1983-06-20

    The design and processing techniques necessary to incorporate bypass diodes within the module encapsulant are presented in this annual report. A comprehensive survey of available pad-mounted PN junction and Schottky diodes led to the selection of Semicon PN junction diode cells for this application. Diode junction-to-heat spreader thermal resistance measurements, performed on a variety of mounted diode chip types and sizes, have yielded values which are consistently below 1/sup 0/C per watt, but show some instability when thermally cycled over the temperature range from -40 to 150/sup 0/C. Based on the results of a detailed thermal analysis, which covered the range of bypass currents from 2 to 20 amperes, three representative experimental modules, each incorporating integral bypass diode/heat spreader assemblies of various sizes, were designed and fabricated. Thermal testing of these modules has enabled the formation of a recommended heat spreader plate sizing relationship. The production cost of three encapsulated bypass diode/heat spreader assemblies were compared with similarly rated externally-mounted packaged diodes. An assessment of bypass diode reliability, which relies heavily on rectifying diode failure rate data, leads to the general conclusion that, when proper designed and installed, these devices will improve the overall reliability of a terrestrial array over a 20 year design lifetime.

  19. Efficiency enhancement in a light-emitting diode with a two-dimensional surface grating photonic crystal

    E-Print Network [OSTI]

    Baba, Toshihiko

    Efficiency enhancement in a light-emitting diode with a two-dimensional surface grating photonic 21 November 2003 We demonstrate a light-emitting diode exhibiting 1.7­2.7-fold enhancement in light light emitting diode LED , the ef- ficiency is limited to several percents by a low light extrac- tion

  20. Optical Safety of LEDs

    SciTech Connect (OSTI)

    none,

    2013-06-01

    Solid-state lighting program technology fact sheet that clarifies the issue of LED lighting safety for the human eye and takes a look at current standards for photobiological safety.

  1. LED Directional Lamps

    SciTech Connect (OSTI)

    2012-11-01

    Solid-state lighting program technology fact sheet that provides an overview of the current performance of LED PAR-, BR-, R-, and AR-shaped lamps, which were all investigated by CALiPER in 2012.

  2. White LED with High Package Extraction Efficiency

    SciTech Connect (OSTI)

    Yi Zheng; Matthew Stough

    2008-09-30

    The goal of this project is to develop a high efficiency phosphor converting (white) Light Emitting Diode (pcLED) 1-Watt package through an increase in package extraction efficiency. A transparent/translucent monolithic phosphor is proposed to replace the powdered phosphor to reduce the scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is proposed between blue LED die and phosphor layer to recover inward yellow emission. At the end of the project we expect to recycle approximately 50% of the unrecovered backward light in current package construction, and develop a pcLED device with 80 lm/W{sub e} using our technology improvements and commercially available chip/package source. The success of the project will benefit luminous efficacy of white LEDs by increasing package extraction efficiency. In most phosphor-converting white LEDs, the white color is obtained by combining a blue LED die (or chip) with a powdered phosphor layer. The phosphor partially absorbs the blue light from the LED die and converts it into a broad green-yellow emission. The mixture of the transmitted blue light and green-yellow light emerging gives white light. There are two major drawbacks for current pcLEDs in terms of package extraction efficiency. The first is light scattering caused by phosphor particles. When the blue photons from the chip strike the phosphor particles, some blue light will be scattered by phosphor particles. Converted yellow emission photons are also scattered. A portion of scattered light is in the backward direction toward the die. The amount of this backward light varies and depends in part on the particle size of phosphors. The other drawback is that yellow emission from phosphor powders is isotropic. Although some backward light can be recovered by the reflector in current LED packages, there is still a portion of backward light that will be absorbed inside the package and further converted to heat. Heat generated in the package may cause a deterioration of encapsulant materials, affecting the performance of both the LED die and phosphor, leading to a decrease in the luminous efficacy over lifetime. Recent studies from research groups at Rensselaer Polytechnic Institute found that, under the condition to obtain a white light, about 40% of the light is transmitted outward of the phosphor layer and 60% of the light is reflected inward.1,2 It is claimed that using scattered photon extraction (SPE) technique, luminous efficacy is increased by 60%. In this project, a transparent/translucent monolithic phosphor was used to replace the powdered phosphor layer. In the normal pcLED package, the powdered phosphor is mixed with silicone either to be deposited on the top of LED die forming a chip level conversion (CLC) white LED or to be casted in the package forming a volume conversion white LED. In the monolithic phosphors there are no phosphor powder/silicone interfaces so it can reduce the light scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is inserted in the white LED package between the blue LED die and phosphor layer. It will selectively transmit the blue light from the LED die and reflect the phosphor's yellow inward emission outward. The two technologies try to recover backward light to the outward direction in the pcLED package thereby improving the package extraction efficiency.

  3. GaSb-based Type-I QW LEDs and addressable arrays operated at wavelengths up to 3.66 m

    E-Print Network [OSTI]

    Sb-based quantum wells (QW) light emitting diodes (LED) and LED arrays operating at room temperature at wavelengths. Kipshidze, D.Westerfeld, D. Snyder, M.Johnson, G. Belenky, "GaSb-Based Type I Quantum Well Light Emitting Diode Addressable Array Operated at Wavelengths up to 3.66 µm", IEEE Photonics Technol. Lett. 21, 1087

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

    E-Print Network [OSTI]

    Chu, Siu Yi Andrew

    1993-01-01

    irm. CD laser diodes are a candidate to be considered as a light source for our proposed fiber optic sensing scheme. A cost effective fiber sensing scheme would enable production of high volume affordable sensing devices for commercial... etc. The input light source of a fiber optic sensing scheme is usually a semiconductor singlemode laser diode, a high coherence light source; or a LED, a low coherence light source. The input optical power is launched into a singlemode or multimode...

  5. A Single-phase Rectifier With Ripple-power Decoupling and Application to LED Lighting 

    E-Print Network [OSTI]

    Tian, Bo

    2015-05-12

    In recent years, Light-Emitting-Diode (LED) is widely used in lighting applications for its high efficacy and high reliability. However, the rectifier, which is required by the LEDs to convert the AC power from the grid into DC power, suffers from...

  6. DUAL USE OF LEDS: SIGNALING AND COMMUNICATIONS IN ITS Grantham Pang, Chi-ho Chan, Hugh Liu, Thomas Kwan

    E-Print Network [OSTI]

    Pang, Grantham

    lights with LEDs is a reduction in power consumption [7]. In addition, incandescent traffic signals burn1 DUAL USE OF LEDS: SIGNALING AND COMMUNICATIONS IN ITS Grantham Pang, Chi-ho Chan, Hugh Liu of light-emitting diodes (LEDs) over incandescent lights is well-supported. This is due to their high

  7. LED Retrofit Project in TSH Basement On July 14 2014, McMaster Facilities Services completed an energy conservation lighting

    E-Print Network [OSTI]

    Thompson, Michael

    replaced with the new LED (light emitting diode) tubes. LEDs have better lighting quality, lower energyLED Retrofit Project in TSH Basement On July 14 2014, McMaster Facilities Services completed an energy conservation lighting retrofit project. About 150 lamps in Togo Salmon Hall basement hallways were

  8. Design and fabrication of high-index-contrast self-assembled texture for light extraction enhancement in LEDs

    E-Print Network [OSTI]

    Sheng, Xing

    We developed a high-index-contrast photonic structure for improving the light extraction efficiency of light-emitting diodes (LEDs) by a self-assembly approach. In this approach, a two-dimensional grating can be ...

  9. Fabrication of poly(p-phenyleneacetylene) light-emitting diodes

    DOE Patents [OSTI]

    Shinar, Joseph (Ames, IA); Swanson, Leland S. (Ames, IA); Lu, Feng (Ames, IA); Ding, Yiwei (Ames, IA)

    1994-08-02

    Acetylene containing poly(p-phenyleneacetylene) (PPA) - based light-emitting diodes (LEDs) are provided. The LEDs are fabricated by coating a hole-injecting electrode, preferably an indium tin oxide (ITO) coated glass substrate, with a PPA polymer, such as a 2,5-dibutoxy or a 2,5-dihexoxy derivative of PPA, dissolved in an organic solvent. This is then followed by evaporating a layer of material capable of injecting electrons, such as A1 or A1/Ca, onto the polymer to form a base electrode. This composition is then annealed to form efficient EL diodes.

  10. Poly (p-phenyleneneacetylene) light-emitting diodes

    DOE Patents [OSTI]

    Shinar, Joseph (Ames, IA); Swanson, Leland S. (Ames, IA); Lu, Feng (Ames, IA); Ding, Yiwei (Ames, IA); Barton, Thomas J. (Ames, IA); Vardeny, Zeev V. (Salt Lake City, UT)

    1994-10-04

    Acetylene containing poly(p-phenyleneacetylene) (PPA) - based light-emitting diodes (LEDs) are provided. The LEDs are fabricated by coating a hole-injecting electrode, preferably an indium tin oxide (ITO) coated glass substrate, with a PPA polymer, such as a 2,5-dibutoxy or a 2,5-dihexoxy derivative of PPA, dissolved in an organic solvent. This is then followed by evaporating a layer of material capable of injecting electrons, such as Al or Al/Ca, onto the polymer to form a base electrode. This composition is then annealed to form efficient EL diodes.

  11. Fabrication of poly(p-phenyleneacetylene) light-emitting diodes

    DOE Patents [OSTI]

    Shinar, J.; Swanson, L.S.; Lu, F.; Ding, Y.

    1994-08-02

    Acetylene-containing poly(p-phenyleneacetylene) (PPA)-based light-emitting diodes (LEDs) are provided. The LEDs are fabricated by coating a hole-injecting electrode, preferably an indium tin oxide (ITO) coated glass substrate, with a PPA polymer, such as a 2,5-dibutoxy or a 2,5-dihexoxy derivative of PPA, dissolved in an organic solvent. This is then followed by evaporating a layer of material capable of injecting electrons, such as Al or Al/Ca, onto the polymer to form a base electrode. This composition is then annealed to form efficient EL diodes. 8 figs.

  12. Vortex diode jet

    DOE Patents [OSTI]

    Houck, Edward D. (Idaho Falls, ID)

    1994-01-01

    A fluid transfer system that combines a vortex diode with a jet ejector to transfer liquid from one tank to a second tank by a gas pressurization method having no moving mechanical parts in the fluid system. The vortex diode is a device that has a high resistance to flow in one direction and a low resistance to flow in the other.

  13. Researchers Say They've Solved the Mystery of LED Lighting "Droop"

    Broader source: Energy.gov [DOE]

    Despite being cool, ultra-efficient and long lasting, the light-emitting diode (LED) faces a problem called “efficiency droop.” New findings from simulations carried out at the National Energy Research Scientific Computer Center (NERSC) have unearthed droop’s elusive cause, researchers say, paving the way for wider LED use. An illustration of nitride-based LEDs.| Courtesy of the National Energy Research Scientific Computing Center.

  14. Coupled optical and electronic simulations of electrically pumped photonic-crystal-based light-emitting diodes

    E-Print Network [OSTI]

    Dutton, Robert W.

    trade-offs in electrically pumped photonic-crystal-based light-emitting diodes. A finite- toelectronic devices, such as light-emitting diodes LEDs and lasers. It has been suggested that a thin slabCoupled optical and electronic simulations of electrically pumped photonic-crystal-based light-emitting

  15. Genetic algorithms used for the optimization of light-emitting diodes and solar thermal collectors

    E-Print Network [OSTI]

    Mayer, Alexandre

    Genetic algorithms used for the optimization of light-emitting diodes and solar thermal collectors developed for the optimization of light-emitting diodes (LED) and solar thermal collectors. The surface a light-extraction efficiency of only 3.7%). The solar thermal collector we considered consists

  16. LED Market Intelligence Report

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousand CubicResource and JobLCLS Operating3 DocumentReview1ImageLED

  17. Colloidal semiconductor nanocrystals as nanoscale emissive probes in light emitting diodes and cell biology

    E-Print Network [OSTI]

    Huang, Hao, Ph. D. Massachusetts Institute of Technology

    2008-01-01

    This thesis employs colloidal semiconductor nanocrystals (NCs) as nanoscale emissive probes to investigate the physics of light emitting diodes (LEDs), as well as to unveil properties of cells that conventional imaging ...

  18. Efficiency loss mechanisms in colloidal quantum-dot light-emitting diodes

    E-Print Network [OSTI]

    Shirasaki, Yasuhiro

    2013-01-01

    Saturated and tunable emission colors make colloidal quantum-dot light-emitting diodes (QD-LEDs) interesting for the next generation of display and lighting technologies. However, there still remain various hurdles to the ...

  19. C. Wetzel et al MRS Internet J. Nitride Semicond. Res. 10, 2 (2005) 1 Development of High Power Green Light Emitting Diode Chips

    E-Print Network [OSTI]

    Wetzel, Christian M.

    2005-01-01

    Power Green Light Emitting Diode Chips C. Wetzel and T. Detchprohm Future Chips Constellation Abstract The development of high emission power green light emitting diodes chips using GaInN/GaN multi production-scale implementation of this green LED die process. Keywords: nitrides, light emitting diode

  20. The Junction Diode Basic Operation

    E-Print Network [OSTI]

    Leach Jr.,W. Marshall

    biased diode. Figure 1(b) shows the diode with a battery connected across it. The polarity of the battery in the p-type side away from the junction. No current can flow. The diode is said to be reverse biased. Figure 1(c) shows the diode with the battery polarity reversed. The battery now tends to cancel out

  1. Transient digitizer with displacement current samplers

    DOE Patents [OSTI]

    McEwan, T.E.

    1996-05-21

    A low component count, high speed sample gate, and digitizer architecture using the sample gates is based on use of a signal transmission line, a strobe transmission line and a plurality of sample gates connected to the sample transmission line at a plurality of positions. The sample gates include a strobe pickoff structure near the strobe transmission line which generates a charge displacement current in response to propagation of the strobe signal on the strobe transmission line sufficient to trigger the sample gate. The sample gate comprises a two-diode sampling bridge and is connected to a meandered signal transmission line at one end and to a charge-holding cap at the other. The common cathodes are reverse biased. A voltage step is propagated down the strobe transmission line. As the step propagates past a capacitive pickoff, displacement current i=c(dv/dT), flows into the cathodes, driving the bridge into conduction and thereby charging the charge-holding capacitor to a value related to the signal. A charge amplifier converts the charge on the charge-holding capacitor to an output voltage. The sampler is mounted on a printed circuit board, and the sample transmission line and strobe transmission line comprise coplanar microstrips formed on a surface of the substrate. Also, the strobe pickoff structure may comprise a planar pad adjacent the strobe transmission line on the printed circuit board. 16 figs.

  2. Transient digitizer with displacement current samplers

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1996-01-01

    A low component count, high speed sample gate, and digitizer architecture using the sample gates is based on use of a signal transmission line, a strobe transmission line and a plurality of sample gates connected to the sample transmission line at a plurality of positions. The sample gates include a strobe pickoff structure near the strobe transmission line which generates a charge displacement current in response to propagation of the strobe signal on the strobe transmission line sufficient to trigger the sample gate. The sample gate comprises a two-diode sampling bridge and is connected to a meandered signal transmission line at one end and to a charge-holding cap at the other. The common cathodes are reverse biased. A voltage step is propagated down the strobe transmission line. As the step propagates past a capacitive pickoff, displacement current i=c(dv/dT), flows into the cathodes, driving the bridge into conduction and thereby charging the charge-holding capacitor to a value related to the signal. A charge amplifier converts the charge on the charge-holding capacitor to an output voltage. The sampler is mounted on a printed circuit board, and the sample transmission line and strobe transmission line comprise coplanar microstrips formed on a surface of the substrate. Also, the strobe pickoff structure may comprise a planar pad adjacent the strobe transmission line on the printed circuit board.

  3. Tunnel junction multiple wavelength light-emitting diodes

    DOE Patents [OSTI]

    Olson, Jerry M. (Lakewood, CO); Kurtz, Sarah R. (Golden, CO)

    1992-01-01

    A multiple wavelength LED having a monolithic cascade cell structure comprising at least two p-n junctions, wherein each of said at least two p-n junctions have substantially different band gaps, and electrical connector means by which said at least two p-n junctions may be collectively energized; and wherein said diode comprises a tunnel junction or interconnect.

  4. Tunnel junction multiple wavelength light-emitting diodes

    DOE Patents [OSTI]

    Olson, J.M.; Kurtz, S.R.

    1992-11-24

    A multiple wavelength LED having a monolithic cascade cell structure comprising at least two p-n junctions, wherein each of said at least two p-n junctions have substantially different band gaps, and electrical connector means by which said at least two p-n junctions may be collectively energized; and wherein said diode comprises a tunnel junction or interconnect. 5 figs.

  5. LED Chips and Packaging for 120 LPW SSL Component

    SciTech Connect (OSTI)

    James Ibbetson

    2009-09-30

    Cree has developed a new, high-efficiency, low-cost, light emitting diode (LED) lamp module that should be capable of replacing standard, halogen, fluorescent and metal halide lamps based on the total cost of ownership. White LEDs are produced by combining one or more saturated color LEDs with a phosphor or other light down-converting media to achieve white broad-band illumination. This two year project addressed LED chip and package efficiency improvements to establish a technology platform suitable for low-cost, high-efficiency commercial luminaires. Novel photonic-crystal LEDs were developed to improve the light extraction efficiency of blue GaN-based LEDs compared to the baseline technology. Improved packaging designs that reduced down-conversion and absorption related light losses, led to a higher overall LED efficiency. Specifically, blue LEDs were demonstrated with light output nearing 600 mW and an external quantum efficiency greater than 60 percent (using 1 mm2 chips at an operating current of 350 mA). The results were achieved using a novel, production capable photonic-crystal LED fabrication process. These LEDs formed the basis for a multi-chip white lamp module prototype, which provided 510 lumens light output at a correlated color temperature (CCT) of 3875 K and an operating current of 350 mA per 1mm2 chip. The overall conversion efficiency at 4100 K improved to ~ 65%. The resulting efficacy is 112 lumens per watt (LPW) â?? a 33% improvement over the start of the project. In addition, a proof-of-concept luminaire was demonstrated that provided a flux of 1700 lumens at a 3842 K CCT.

  6. LED Record Efficacy and Brightness

    Broader source: Energy.gov [DOE]

    Designed for general lighting applications such as street, industrial, and parking garage lighting, the Cree XLamp® power LED sets new records for LED brightness and efficacy, up to 85 lm/W at 350 mA. The XLamp utilizes Cree's performance breakthrough EZBright™ LED chip; both products include technology that was developed in part with R&D funding support from DOE.

  7. Tests gauge LED sensors for fuel-dye measurements

    SciTech Connect (OSTI)

    Ozanich, Richard M.; Lucke, Richard B.; Melville, Angela M.; Wright, Bob W.

    2009-10-19

    The goal of this work was to develop a low cost, robust sensor to allow direct measurement of Solvent Red 164 dye concentration in off-road fuel at refineries and fuel terminals. Optical absorption sensors based on light emitting diodes (LEDs) are rugged, low-cost, have low power consumption, and can be designed to be intrinsically safe.LED-based systems have been used in a variety of chemical detection applications including heavy metals, pH, CO2, and O2. The approach for this work was to develop a sensor that could be mounted on a pipeline sight glass, precluding the need for direct contact of the sensor with the fuel. Below is described the design and testing of three different LED/photodiode sensors utilizing reflectance spectrometry for the measurement of dye concentration.

  8. Development of an LED reference light source for calibration of radiographic imaging detectors

    E-Print Network [OSTI]

    M. Weierganz; D. Bar; B. Bromberger; V. Dangendorf; G. Feldman; M. B. Goldberg; M. Lindemann; I. Mor; K. Tittelmeier; D. Vartsky

    2010-02-08

    A stable reference light source based on an LED (Light Emission Diode) is presented for stabilizing the conversion gain of the opto-electronic system of a gamma- and fast-neutron radiographic and tomographic imaging device. A constant fraction of the LED light is transported to the image plane of the camera and provides a stable reference exposure. This is used to normalize the images during off-line image processing. We have investigated parameters influencing the stability of LEDs and developed procedures and criteria to prepare and select LEDs suitable for delivering stable light outputs for several 100 h of operation.

  9. Improved hole distribution in InGaN/GaN light-emitting diodes with graded thickness quantum barriers

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    is 48.3%. Moreover, the light output power was enhanced from 770 mW for the ETQB LEDs to 870 m; accepted 3 June 2013; published online 19 June 2013) InGaN/GaN light-emitting diodes (LEDs) with graded , which is much smaller than that of the conventional equal-thickness quantum barriers (ETQB) LED, which

  10. Flip-chip light emitting diode with resonant optical microcavity

    SciTech Connect (OSTI)

    Gee, James M.; Bogart, Katherine H.A.; Fischer, Arthur J.

    2005-11-29

    A flip-chip light emitting diode with enhanced efficiency. The device structure employs a microcavity structure in a flip-chip configuration. The microcavity enhances the light emission in vertical modes, which are readily extracted from the device. Most of the rest of the light is emitted into waveguided lateral modes. Flip-chip configuration is advantageous for light emitting diodes (LEDs) grown on dielectric substrates (e.g., gallium nitride LEDs grown on sapphire substrates) in general due to better thermal dissipation and lower series resistance. Flip-chip configuration is advantageous for microcavity LEDs in particular because (a) one of the reflectors is a high-reflectivity metal ohmic contact that is already part of the flip-chip configuration, and (b) current conduction is only required through a single distributed Bragg reflector. Some of the waveguided lateral modes can also be extracted with angled sidewalls used for the interdigitated contacts in the flip-chip configuration.

  11. Junction temperature, spectral shift, and efficiency in GaInN-based blue and green light emitting diodes

    E-Print Network [OSTI]

    Wetzel, Christian M.

    Keywords: GaInN/GaN Light emitting diode temperature Micro-Raman Photoluminescence Electroluminescence well light emitting diode (LED) dies is analyzed by micro-Raman, photoluminescence, cathodoluminescenceJunction temperature, spectral shift, and efficiency in GaInN-based blue and green light emitting

  12. Thickness-dependent changes in the optical properties of PPV-and PF-based polymer light emitting diodes

    E-Print Network [OSTI]

    Carter, Sue

    the thickness-dependent optical properties of single layer polymer light emitting diodes for two materials, poly the electronic and optical properties of these materials in light emitting diode LED structures.2 OurThickness-dependent changes in the optical properties of PPV- and PF-based polymer light emitting

  13. LOW-COST LED LUMINAIRE FOR GENERAL ILLUMINATION

    SciTech Connect (OSTI)

    Lowes, Ted

    2014-07-31

    During this two-year Solid-State Lighting (SSL) Manufacturing R&D project Cree developed novel light emitting diode (LED) technologies contributing to a cost-optimized, efficient LED troffer luminaire platform emitting at ~3500K correlated color temperature (CCT) at a color rendering index (CRI) of >90. To successfully achieve program goals, Cree used a comprehensive approach to address cost reduction of the various optical, thermal and electrical subsystems in the luminaire without impacting performance. These developments built on Cree’s high- brightness, low-cost LED platforms to design a novel LED component architecture that will enable low-cost troffer luminaire designs with high total system efficacy. The project scope included cost reductions to nearly all major troffer subsystems as well as assembly costs. For example, no thermal management components were included in the troffer, owing to the optimized distribution of compact low- to mid-power LEDs. It is estimated that a significant manufacturing cost savings will result relative to Cree’s conventional troffers at the start of the project. A chief project accomplishment was the successful development of a new compact, high-efficacy LED component geometry with a broad far-field intensity distribution and even color point vs. emission angle. After further optimization and testing for production, the Cree XQ series of LEDs resulted. XQ LEDs are currently utilized in Cree’s AR series troffers, and they are being considered for use in other platforms. The XQ lens geometry influenced the independent development of Cree’s XB-E and XB-G high-voltage LEDs, which also have a broad intensity distribution at high efficacy, and are finding wide implementation in Cree’s omnidirectional A-lamps.

  14. Improved Cognitive Function After Transcranial, Light-Emitting Diode Treatments in Chronic, Traumatic Brain Injury: Two Case Reports

    E-Print Network [OSTI]

    Naeser, Margaret A.

    Objective: Two chronic, traumatic brain injury (TBI) cases, where cognition improved following treatment with red and near-infrared light-emitting diodes (LEDs), applied transcranially to forehead and scalp areas, are ...

  15. Metacapacitors for LED Lighting: Metacapacitors

    SciTech Connect (OSTI)

    None

    2010-09-02

    ADEPT Project: The CUNY Energy Institute is developing less expensive, more efficient, smaller, and longer-lasting power converters for energy-efficient LED lights. LEDs produce light more efficiently than incandescent lights and last significantly longer than compact fluorescent bulbs, but they require more sophisticated power converter technology, which increases their cost. LEDs need more sophisticated converters because they require a different type of power (low voltage direct current, or DC) than what's generally supplied by power outlets. The CUNY Energy Institute is developing sophisticated power converters for LEDs that contain capacitors made from new, nanoscale materials. Capacitors are electrical components that are used to store energy. CUNY's unique capacitors are configured with advanced power circuits to more efficiently control and convert power to the LED lighting source. They also eliminate the need for large magnetic components, instead relying on networks of capacitors that can be easily printed on plastic substrate. CUNY's prototype LED power converter already meets DOE's 2020 projections for the energy efficiency of LED power converters.

  16. Recessed LED Downlights | Department of Energy

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

    Recessed LED Downlights Recessed LED Downlights A Dept of Energy Solid-State Lighting Program technology fact sheet on recessed LED downlights. recesseddownlight.pdf More...

  17. LED Frequently Asked Questions | Department of Energy

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

    Frequently Asked Questions LED Frequently Asked Questions EERE Solid-State Lighting LED Factsheet ledbasics.pdf More Documents & Publications LED Frequently Asked Questions SSL...

  18. Demonstration Assessment of LED Roadway Lighting: Philadelphia...

    Office of Scientific and Technical Information (OSTI)

    LED Roadway Lighting: Philadelphia, PA Royer, Michael P.; Tuenge, Jason R.; Poplawski, Michael E. Roadway Lighting; Solid-state lighting; LED lighting; SSL; LED; GATEWAY Roadway...

  19. LED Lighting: Applying Lessons Learned from the CFL Experience

    SciTech Connect (OSTI)

    McCullough, Jeffrey J.; Gilbride, Theresa L.; Gordon, Kelly L.; Ledbetter, Marc R.; Sandahl, Linda J.; Ton, My K.

    2008-08-20

    Light emitting diode (LED) technology has emerged as an exciting new lighting alternative with the potential for significant energy savings. There is concern, however, that white light LEDs for general illumination could take a long, bumpy course similar to another energy-efficient lighting technology – compact fluorescent lights (CFLs). Recognizing the significant potential energy-efficient lighting has to reduce U.S. energy consumption, Congress mandated in the Energy Policy Act of 2005 that the U.S. Department of Energy (DOE) develop Solid State Lighting (SSL) through a Next Generation Lighting Initiative. DOE’s first step was to analyze the market introduction of compact fluorescent lighting to determine what lessons could be learned to smooth the introduction of SSL in the United States (Sandahl et al. 2006). This paper summarizes applicable lessons learned from the market introduction of CFLs and describe how DOE and others are applying those lessons to speed the development and market introduction of energy-efficient LED lighting for general illumination applications. A description of the current state of LED technology and compares LEDs to incandescent, fluorescent, and halogen lights is also provided.

  20. Regenerative rotary displacer Stirling engine

    SciTech Connect (OSTI)

    Isshiki, Naotsugu; Watanabe, Hiroichi; Raggi, L.; Isshiki, Seita; Hirata, Koichi

    1996-12-31

    A few rotary displacer Stirling engines in which the displacer has one gas pocket space at one side and rotates in a main enclosed cylinder, which is heated from one side and cooled from opposite side without any regenerator, have been studied for some time by the authors. The authors tried to improve this engine by equipping it with a regenerator, because without a regenerator, pressure oscillation and efficiency are too small. Here, several types of regenerative rotary displacer piston Stirling engines are proposed. One is the contra-rotating tandem two disc type displacer engine using axial heat conduction through side walls or by heat pipes and another is a single disc type with circulating fluid regenerator or heat pipes. Stirling engines of this new rotary displacer type are thought to attain high speed. Here, experimental results of the original rotary displacer Stirling engine without a regenerator, and one contra-rotating tandem displacer engine with side wall regenerator by axial heat conduction are reported accompanied with a discussion of the results.

  1. Maintenance Practices for LED Streetlights

    Broader source: Energy.gov [DOE]

    This April 14, 2014 webinar answered important questions about the maintenance and reliability of LED streetlights, and how to take these issues into account when planning and preparing for a...

  2. A hole modulator for InGaN/GaN light-emitting diodes Zi-Hui Zhang, Zabu Kyaw, Wei Liu, Yun Ji, Liancheng Wang, Swee Tiam Tan, Xiao Wei Sun, and Hilmi Volkan

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    well on optical power of light-emitting diodes Appl. Phys. Lett. 96, 051113 (2010); 10-emitting diodes (LEDs) due to the ineffective hole injection into the InGaN/GaN multiple quantum well (MQW) active in the p-GaN layer can be enhanced. Furthermore, the hole modulator is adopted in the InGaN/GaN LEDs, which

  3. The Laser DiodeThe Laser Diode Jason HillJason Hill

    E-Print Network [OSTI]

    La Rosa, Andres H.

    a Laser Diode Works Edge Emitting Laser Diode Operates similar to a Light Emitting DiodeOperates similar to a Light Emitting Diode Active medium is a semiconductor pActive medium is a semiconductor p--n junctionn Operates similar to a Light Emitting DiodeOperates similar to a Light Emitting Diode Active medium

  4. Literature Review of Displacement Ventilation 

    E-Print Network [OSTI]

    Cho, S.; Im, P.; Haberl, J. S.

    2005-01-01

    Performance Evaluation and Design Guidelines for Displacement Ventilation” by Chen and Clicksman (2003), were used to begin the literature search. Their references include papers, articles, and web sites presenting major contributions to the understanding...

  5. Displacement sensing system and method

    DOE Patents [OSTI]

    VunKannon, Jr., Robert S

    2006-08-08

    A displacement sensing system and method addresses demanding requirements for high precision sensing of displacement of a shaft, for use typically in a linear electro-dynamic machine, having low failure rates over multi-year unattended operation in hostile environments. Applications include outer space travel by spacecraft having high-temperature, sealed environments without opportunity for servicing over many years of operation. The displacement sensing system uses a three coil sensor configuration, including a reference and sense coils, to provide a pair of ratio-metric signals, which are inputted into a synchronous comparison circuit, which is synchronously processed for a resultant displacement determination. The pair of ratio-metric signals are similarly affected by environmental conditions so that the comparison circuit is able to subtract or nullify environmental conditions that would otherwise cause changes in accuracy to occur.

  6. LASER DIODE TECHNOLOGY AND APPLICATIONS Submitted to

    E-Print Network [OSTI]

    La Rosa, Andres H.

    and a normal diode and a light emitting diode. I will also define the terms homojunction and heterojunction, and is the main source of light in a light-emitting diode. Under suitable conditions, the electron and the hole

  7. Thermoelectric Generator (TEG) Fuel Displacement Potential using...

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

    Fuel Displacement Potential using Engine-in-the-Loop and Simulation Thermoelectric Generator (TEG) Fuel Displacement Potential using Engine-in-the-Loop and Simulation Assessment...

  8. Clean Cities Regional Support & Petroleum Displacement Awards...

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

    Regional Support & Petroleum Displacement Awards Clean Cities Regional Support & Petroleum Displacement Awards 2009 DOE Hydrogen Program and Vehicle Technologies Program Annual...

  9. Diffusion injected multi-quantum well light-emitting diode structure

    SciTech Connect (OSTI)

    Riuttanen, L., E-mail: lauri.riuttanen@aalto.fi; Nykänen, H.; Svensk, O.; Suihkonen, S.; Sopanen, M. [Department of Micro- and Nanosciences, Aalto University, P.O. Box 13500, FI-00076 Aalto (Finland); Kivisaari, P.; Oksanen, J.; Tulkki, J. [Department of Biomedical Engineering and Computational Science, Aalto University, P.O. Box 12200, FI-00076 Aalto (Finland)

    2014-02-24

    The attention towards light-emitting diode (LED) structures based on nanowires, surface plasmon coupled LEDs, and large-area high-power LEDs has been increasing for their potential in increasing the optical output power and efficiency of LEDs. In this work we demonstrate an alternative way to inject charge carriers into the active region of an LED, which is based on completely different current transport mechanism compared to conventional current injection approaches. The demonstrated structure is expected to help overcoming some of the challenges related to current injection with conventional structures. A functioning III-nitride diffusion injected light-emitting diode structure, in which the light-emitting active region is located outside the pn-junction, is realized and characterized. In this device design, the charge carriers are injected into the active region by bipolar diffusion, which could also be utilized to excite otherwise challenging to realize light-emitting structures.

  10. High efficiency III-nitride light-emitting diodes

    DOE Patents [OSTI]

    Crawford, Mary; Koleske, Daniel; Cho, Jaehee; Zhu, Di; Noemaun, Ahmed; Schubert, Martin F; Schubert, E. Fred

    2013-05-28

    Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.

  11. SciTech Connect: "light emitting diode"

    Office of Scientific and Technical Information (OSTI)

    light emitting diode" Find + Advanced Search Term Search Semantic Search Advanced Search All Fields: "light emitting diode" Semantic Semantic Term Title: Full Text:...

  12. Enhancement of light extraction efficiency of InGaN quantum wells light emitting diodes using SiO2/polystyrene microlens arrays

    E-Print Network [OSTI]

    Gilchrist, James F.

    in the Fresnel reflection. Improvement of output power by 219% for InGaN quantum wells LEDs emitting at peakGaN quantum wells light emitting diodes LEDs using SiO2/polystyrene microspheres was demonstrated experimentally. The utilization of SiO2/polystyrene microlens arrays on InGaN quantum wells LEDs, deposited via

  13. LED lamp color control system and method

    DOE Patents [OSTI]

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A.M.

    2013-02-05

    An LED lamp color control system and method including an LED lamp having an LED controller 58; and a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 determines whether the LED source 80 is in a feedback controllable range, stores measured optical flux for the LED source 80 when the LED source 80 is in the feedback controllable range, and bypasses storing the measured optical flux when the LED source 80 is not in the feedback controllable range.

  14. LED lamp power management system and method

    DOE Patents [OSTI]

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A. M.

    2013-03-19

    An LED lamp power management system and method including an LED lamp having an LED controller 58; a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 reduces power loss in one of the channel switch 62 and the shunt switch 68 when LED lamp electronics power loss (P.sub.loss) exceeds an LED lamp electronics power loss limit (P.sub.lim); and each of the channel switches 62 receives a channel switch control signal 63 from the LED controller 58 and each of the shunt switches 68 receives a shunt switch control signal 69 from the LED controller 58.

  15. Magical Mystery Devices or Not: How do LED Lamps and Luminaires Really Measure-Up?

    SciTech Connect (OSTI)

    Paget, Maria L.; McCullough, Jeffrey J.; Steward, Heidi E.

    2008-08-15

    Solid-state lighting products for general lighting applications are now gaining a market presence, and more and more people are asking, “Which of these are ‘good’ products? Do they perform as claimed? How do they compare? Light Emitting Diodes (LEDs) differ from other light sources enough to require new procedures for measuring their performance and comparing to other lighting options, so both manufacturers and buyers are facing a learning curve. The energy-efficiency community has traditionally compared light sources based on system efficacy: rated lamp lumens divided by power into the system. This doesn’t work for LEDs because there are no standard LED “lamp” packages and no lamp ratings, and because LED performance depends heavily on thermal, electrical, and optical design of complete lighting unit or ‘luminaire’. Luminaire efficacy is the preferred metric for LEDs because it measures the net light output from the luminaire divided by power into the system.

  16. INTRODUCTION TO ARDUINO AND LEDS

    E-Print Network [OSTI]

    7/16/13 1 INTRODUCTION TO ARDUINO AND LEDS Activity one: Make sure everybody is up and running Arduino #12;7/16/13 2 Arduino USB Interface External Power ATmega328 Analog Inputs Digital I Arduino Programming Load Examples - Basics - Blink Arduino SW system Two required functions void setup

  17. Current crowding in GaInN / GaN LEDs grown on insulating substrates X. Guo, E. F. Schubert and J. Jahns

    E-Print Network [OSTI]

    Jahns, Jürgen

    Current crowding in GaInN / GaN LEDs grown on insulating substrates X. Guo, E. F. Schubert and J. Jahns Current crowding in mesa-structure GaInN/GaN light-emitting diodes (LEDs) grown on insulating and a saturation of the optical output power at high injection currents. It is shown that the optical power

  18. DISPLACEMENT BASED SEISMIC DESIGN METHODS.

    SciTech Connect (OSTI)

    HOFMAYER,C.MILLER,C.WANG,Y.COSTELLO,J.

    2003-07-15

    A research effort was undertaken to determine the need for any changes to USNRC's seismic regulatory practice to reflect the move, in the earthquake engineering community, toward using expected displacement rather than force (or stress) as the basis for assessing design adequacy. The research explored the extent to which displacement based seismic design methods, such as given in FEMA 273, could be useful for reviewing nuclear power stations. Two structures common to nuclear power plants were chosen to compare the results of the analysis models used. The first structure is a four-story frame structure with shear walls providing the primary lateral load system, referred herein as the shear wall model. The second structure is the turbine building of the Diablo Canyon nuclear power plant. The models were analyzed using both displacement based (pushover) analysis and nonlinear dynamic analysis. In addition, for the shear wall model an elastic analysis with ductility factors applied was also performed. The objectives of the work were to compare the results between the analyses, and to develop insights regarding the work that would be needed before the displacement based analysis methodology could be considered applicable to facilities licensed by the NRC. A summary of the research results, which were published in NUREGICR-6719 in July 2001, is presented in this paper.

  19. Philadelphia International Airport Apron Lighting: LED System...

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

    Philadelphia International Airport Apron Lighting: LED System Performance in a Trial Installation Philadelphia International Airport Apron Lighting: LED System Performance in a...

  20. Testimonials - Partnerships in LED Lighting - Philips Lumileds...

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

    LED Lighting - Philips Lumileds Lighting, LLC Testimonials - Partnerships in LED Lighting - Philips Lumileds Lighting, LLC Addthis An error occurred. Try watching this video on...

  1. Laterally injected light-emitting diode and laser diode

    DOE Patents [OSTI]

    Miller, Mary A.; Crawford, Mary H.; Allerman, Andrew A.

    2015-06-16

    A p-type superlattice is used to laterally inject holes into an III-nitride multiple quantum well active layer, enabling efficient light extraction from the active area. Laterally-injected light-emitting diodes and laser diodes can enable brighter, more efficient devices that impact a wide range of wavelengths and applications. For UV wavelengths, applications include fluorescence-based biological sensing, epoxy curing, and water purification. For visible devices, applications include solid state lighting and projection systems.

  2. Free displacer and Ringbom displacer for a Malone refrigerator

    SciTech Connect (OSTI)

    Swift, G.W.; Brown, A.O.

    1994-05-01

    Malone refrigeration uses a liquid near its critical point (instead of the customary gas) as the working fluid in a Stirling, Brayton, or similar regenerative or recuperative cycle. Thus far, we have focused on the Stirling cycle, to avoid the difficult construction of the high-pressure-difference counterflow recuperator required for a Brayton machine. Our first Malone refrigerator used liquid propylene (C{sub 3}H{sub 6}) in a double-acting 4-cylinder Stirling configuration. First measurements with a free displacer used in a liquid working fluid are presented. The displacer was operated both in harmonic mode and in Ringbom mode, in liquid carbon dioxide. The results are in reasonable agreement with expectations.

  3. Development of ZnO Based Light Emitting Diodes and Laser Diodes

    E-Print Network [OSTI]

    Kong, Jieying

    2012-01-01

    E. Fred Schubert, Light-Emitting Diodes, New York (2006) [8]ZnO homojunction light emitting diode 3. 1. Motivation ofAlGaAs red light-emitting diodes, in: G.B. Stringfellow, M.

  4. Amber light-emitting diode comprising a group III-nitride nanowire active region

    DOE Patents [OSTI]

    Wang, George T.; Li, Qiming; Wierer, Jr., Jonathan J.; Koleske, Daniel

    2014-07-22

    A temperature stable (color and efficiency) III-nitride based amber (585 nm) light-emitting diode is based on a novel hybrid nanowire-planar structure. The arrays of GaN nanowires enable radial InGaN/GaN quantum well LED structures with high indium content and high material quality. The high efficiency and temperature stable direct yellow and red phosphor-free emitters enable high efficiency white LEDs based on the RGYB color-mixing approach.

  5. Photoionization of optically trapped ultracold atoms with a high-power light-emitting diode

    SciTech Connect (OSTI)

    Goetz, Simone; Hoeltkemeier, Bastian; Amthor, Thomas; Weidemueller, Matthias [Physikalisches Institut, Universitaet Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg (Germany)

    2013-04-15

    Photoionization of laser-cooled atoms using short pulses of a high-power light-emitting diode (LED) is demonstrated. Light pulses as short as 30 ns have been realized with the simple LED driver circuit. We measure the ionization cross section of {sup 85}Rb atoms in the first excited state, and show how this technique can be used for calibrating efficiencies of ion detector assemblies.

  6. LEDS | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EAInvervar HydroElectric Cooperative(Redirected fromUni LandLEDS Home

  7. Demonstration of LED Street Lighting

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnical Report:Speeding accessby aLED Street Lighting Host Site: City of Kansas City,

  8. Advanced Leds | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowaWisconsin: Energy Resources JumpAdelan UK LtdWisconsin:Missouri:LLCLeadLeds

  9. Enhanced vbasis laser diode package

    DOE Patents [OSTI]

    Deri, Robert J.; Chen, Diana; Bayramian, Andy; Freitas, Barry; Kotovsky, Jack

    2014-08-19

    A substrate having an upper surface and a lower surface is provided. The substrate includes a plurality of v-grooves formed in the upper surface. Each v-groove includes a first side and a second side perpendicular to the first side. A laser diode bar assembly is disposed within each of the v-grooves and attached to the first side. The laser diode bar assembly includes a first adhesion layer disposed on the first side of the v-groove, a metal plate attached to the first adhesion layer, a second adhesion layer disposed over the metal plate, and a laser diode bar attached to the second adhesion layer. The laser diode bar has a coefficient of thermal expansion (CTE) substantially similar to that of the metal plate.

  10. Design for enhanced thermo-electric pumping in light emitting diodes Dodd J. Gray Jr., Parthiban Santhanam, and Rajeev J. Ram

    E-Print Network [OSTI]

    Ram, Rajeev J.

    of EL cooling in an LED, the low light power ($70 pW or $1.1 Â 10À9 W mmÀ2 ) and elevated LED tem for optimization of thermo-electric pumping in light emitting diodes (LEDs). We use a finite element model for charge transport in a GaInAsSb/GaSb double hetero-junction LED that is verified experimentally

  11. Flexible Fiber Nanogenerator with 209 V Output Voltage Directly Powers a Light-Emitting Diode

    E-Print Network [OSTI]

    Wang, Zhong L.

    a commercial light-emitting diode (LED) without the energy storage process. KEYWORDS: Nanogenerator, high and so on. Among these systems, many of them need an energy storage unit to make them work properly. This energy storage circuit adds much complexity to the self-powered system and hinders its capacity to work

  12. Water Mist Suppression in Conjunction with Displacement

    E-Print Network [OSTI]

    Hickman, Mark

    Water Mist Suppression in Conjunction with Displacement Ventilation By Benjamin Piers Hume-2758 #12;#12;Displacement Water Mist System Masters of Fire Engineering Thesis 2003 i A man of genius makes Water Mist System Masters of Fire Engineering Thesis 2003 ii #12;Displacement Water Mist System Masters

  13. White Light Emitting Diode Development for General Illumination Applications

    SciTech Connect (OSTI)

    James Ibbetson

    2006-05-01

    This report contains a summary of technical achievements during a 3-year project aimed at developing the chip and packaging technology necessary to demonstrate efficient, high flux light-emitting diode (LED) arrays using Cree's gallium nitride/silicon carbide (GaN/SiC) LED technology as the starting point. Novel chip designs and fabrication processes are described that led to high power blue LEDs that achieved 310 mW of light output at 350 mA drive current, corresponding to quantum and wall plug efficiencies of 32.5% and 26.5%, respectively. When combined with phosphor, high power white LEDs with luminous output of 67 lumens and efficacy of 57 lumens per watt were also demonstrated. Advances in packaging technology are described that enabled compact, multi-chip white LED lamp modules with 800-1000 lumens output at efficacies of up to 55 lumens per watt. Lamp modules with junction-to-ambient thermal resistance as low as 1.7 C/watt have also been demonstrated.

  14. Light emitting diode package element with internal meniscus for bubble free lens placement

    DOE Patents [OSTI]

    Tarsa, Eric; Yuan, Thomas C.; Becerra, Maryanne; Yadev, Praveen

    2010-09-28

    A method for fabricating a light emitting diode (LED) package comprising providing an LED chip and covering at least part of the LED chip with a liquid encapsulant having a radius of curvature. An optical element is provided having a bottom surface with at least a portion having a radius of curvature larger than the liquid encapsulant. The larger radius of curvature portion of the optical element is brought into contact with the liquid encapsulant. The optical element is then moved closer to the LED chip, growing the contact area between said optical element and said liquid encapsulant. The liquid encapsulant is then cured. A light emitting diode comprising a substrate with an LED chip mounted to it. A meniscus ring is on the substrate around the LED chip with the meniscus ring having a meniscus holding feature. An inner encapsulant is provided over the LED chip with the inner encapsulant having a contacting surface on the substrate, with the meniscus holding feature which defines the edge of the contacting surface. An optical element is included having a bottom surface with at least a portion that is concave. The optical element is arranged on the substrate with the concave portion over the LED chip. A contacting encapsulant is included between the inner encapsulant and optical element.

  15. A Comparison of Infrared Light Emitting Diodes (IR-LED) versus Infrared

    E-Print Network [OSTI]

    Girard, James W.; Bogin, Gregory E; Mack, John Hunter; Chen, J-Y; Dibble, Rober W

    2005-01-01

    since combustion in lean premixed gas turbines takes placePremixed Gas Turbines”, 26th Symp. (Intern. ) on Combustion,

  16. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting, Phase I

    SciTech Connect (OSTI)

    Myer, M. A.; Goettel, R. T.

    2010-06-22

    U.S. DOE Solid-State Lighting Technology Demonstration GATEWAY Program Report on the TJMaxx Demonstration.

  17. Demonstration Assessment of Light-Emitting Diode (LED) Residential Downlights and Undercabinet Lights

    SciTech Connect (OSTI)

    None

    2008-10-01

    This document is a report of observations and results obtained from a lighting demonstration project conducted under the U.S. Department of Energy (DOE) Solid-State Lighting (SSL) GATEWAY Demonstration Program.

  18. Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting

    SciTech Connect (OSTI)

    None

    2009-10-01

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology combined with occupancy sensors in a set of upright grocery store freezer cases.

  19. DOE Science Showcase - Light-emitting Diode (LED) Lighting Research | OSTI,

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal GasAdministration Medal01TechnicalScientific and TechnicalOfficeScientificUS Dept of

  20. Demonstration Assessment of Light-Emitting Diode (LED) Post-Top Lighting at

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnical Report: Achievements ofCOMPOSITION OF VAPORSSeries)SupportedDavid J.andCentral Park

  1. Demonstration Assessment of Light-Emitting Diode (LED) Accent Lighting at

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(Journal Article) |the

  2. Demonstration Assessment of Light-Emitting Diode (LED) Accent Lighting at

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(Journal Article) |thethe

  3. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(Journal Article) |thetheat

  4. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(Journal Article)

  5. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(Journal Article)in

  6. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(Journal Article)inin

  7. Demonstration Assessment of Light-Emitting Diode (LED) Post-Top Lighting at

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(Journal

  8. Demonstration Assessment of Light-Emitting Diode (LED) Post-Top Lighting at

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(JournalCentral Park in New

  9. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(JournalCentral Park in

  10. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(JournalCentral Park inthe

  11. Demonstration Assessment of Light-Emitting Diode (LED) Street Lighting Host

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(JournalCentral Park

  12. Demonstration Assessment of Light-Emitting Diode (LED) Street Lighting Host

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interaction (Journal Article)(JournalCentral ParkSite:

  13. LEDs for Street Lighting—Here Today

    SciTech Connect (OSTI)

    2013-11-29

    Fact sheet that provides a brief overview of the viability of LED street lighting in municipalities and highlights case studies of two cities—Los Angeles and Seattle—that have invested in LED street lighting.

  14. UNDERSTANDING LED COLOR-TUNABLE PRODUCTS

    Broader source: Energy.gov [DOE]

    LED luminaires with the ability to deliver varying light color have been on the architectural lighting market since the early days of LED lighting, but improved efficacy, colors, controls, and...

  15. LED Solutions for the Dark Hours

    Energy Savers [EERE]

    technologies 5 LEDs for Street and Roadway Lighting Portland, OR Philadelphia, PA New York, NY Kansas City, MO 6 Boston Las Vegas Seattle Number of LED Replacements to Date (4...

  16. DOE ZERH Webinar: LED Lighting Efficiency

    Broader source: Energy.gov [DOE]

    Description: LED lighting offers efficiency and performance benefits we've never seen in traditional lighting technologies. Commercial buildings have seen rapid growth in LED deployment, and in the...

  17. Smart Lighting: LED Implementation and Ambient Communication Applications

    E-Print Network [OSTI]

    Agogino, Alice M.

    Smart Lighting: LED Implementation and Ambient Communication Applications by Nicholas Adrian Galano............................................................................................................................................1 LED Implementation..........................................................................................................................2 LED Energy Usage

  18. Interferometric fiber optic displacement sensor

    DOE Patents [OSTI]

    Farah, J.

    1999-04-06

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

  19. Interferometric fiber optic displacement sensor

    DOE Patents [OSTI]

    Farah, John (M.I.T. Branch P.O. Box 301, Cambridge, MA 02139)

    1995-01-01

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

  20. Interferometric fiber optic displacement sensor

    DOE Patents [OSTI]

    Farah, J.

    1995-05-30

    A method is presented to produce a change in the optical path length in the gap between two single mode optical fibers proportional to the lateral displacement of either fiber end normal to its axis. This is done with the use of refraction or diffraction at the interface between a guiding and non-guiding media to change the direction of propagation of the light in the gap. A method is also presented for laying a waveguide on a cantilever so that the displacement of the tip of the cantilever produces a proportional path length change in the gap by distancing the waveguide from the neutral axis of the cantilever. The fiber is supported as a cantilever or a waveguide is deposited on a micromachined cantilever and incorporated in an interferometer which is made totally on a silicon substrate with the use of integrated-optic technology. A resonant element in the form of a micro-bridge is incorporated in the ridge waveguide and produces a frequency output which is readily digitizeable and immune to laser frequency noise. Finally, monolithic mechanical means for phase modulation are provided on the same sensor substrate. This is done by vibrating the cantilever or micro-bridge either electrically or optically. 29 figs.

  1. Interferometric fiber optic displacement sensor

    DOE Patents [OSTI]

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

    1999-01-01

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

  2. LED Watch: The Outlook for OLEDs

    Broader source: Energy.gov [DOE]

    December 2014 LED Watch: The Outlook for OLEDs James Brodrick, U.S. Department of Energy LD+A Magazine

  3. Enhancement of light extraction efficiency of InGaN quantum wells light emitting diodes using Si O 2 /polystyrene microlens arrays

    E-Print Network [OSTI]

    Gilchrist, James F.

    November 2007 Improvement of light extraction efficiency of InGaN quantum wells light emitting diodes LEDs microlens arrays on InGaN quantum wells LEDs, deposited via rapid convective deposition, allows the increase of the effective photon escape cone and reduction in the Fresnel reflection. Improvement of output power by 219

  4. InGaN/GaN multiple-quantum-well light-emitting diodes with a grading InN composition suppressing the Auger recombination

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    ) In conventional InGaN/GaN light-emitting diodes (LEDs), thin InGaN quantum wells are usually adopted to mitigate recombination scales with the third power of the carrier density. As a result, the efficiency droop of the Auger recombination severely limits the LED performance. Here, we proposed and showed wide InGaN quantum wells

  5. Method of making diode structures

    DOE Patents [OSTI]

    Compaan, Alvin D.; Gupta, Akhlesh

    2006-11-28

    A method of making a diode structure includes the step of depositing a transparent electrode layer of any one or more of the group ZnO, ZnS and CdO onto a substrate layer, and depositing an active semiconductor junction having an n-type layer and a p-type layer onto the transparent electrode layer under process conditions that avoid substantial degradation of the electrode layer. A back electrode coating layer is applied to form a diode structure.

  6. Software Enabled Virtually Variable Displacement Pumps -Theoretical and Experimental Studies

    E-Print Network [OSTI]

    Li, Perry Y.

    Software Enabled Virtually Variable Displacement Pumps - Theoretical and Experimental Studies the functional equivalent of a variable displacement pump. This approach combines a fixed displacement pump valve control, without many of the shortcomings of commercially available variable displacement pumps

  7. Feedback-Controlled LED Photobioreactor for Photophysiological Studies of Cyanobacteria

    SciTech Connect (OSTI)

    Melnicki, Matthew R.; Pinchuk, Grigoriy E.; Hill, Eric A.; Kucek, Leo A.; Stolyar, Sergey; Fredrickson, Jim K.; Konopka, Allan; Beliaev, Alex S.

    2013-04-09

    A custom photobioreactor (PBR) was designed to enable automatic light adjustments using computerized feedback control. A black anodized aluminum enclosure, constructed to surround the borosilicate reactor vessel, prevents the transmission of ambient light and serves as a mount for arrays of light-emitting diodes (LEDs). The high-output LEDs provide narrow-band light of either 630 or 680 nm for preferential excitation of the cyanobacterial light-harvesting pigments, phycobilin or chlorophyll a, respectively. Custom developed software BioLume provides automatic control of optical properties and a computer feedback loop can automatically adjust the incident irradiance as necessary to maintain a fixed transmitted light through the culture, based on user-determined set points. This feedback control serves to compensate for culture dynamics which have optical effects, (e.g., changing cell density, pigment adaptations) and thus can determine the appropriate light conditions for physiological comparisons or to cultivate light-sensitive strains, without prior analyses. The LED PBR may also be controlled as a turbidostat, using a feedback loop to continuously adjust the rate of media-dilution based on the transmitted light measurements, with a fast and precise response. This cultivation system gains further merit as a high-performance analytical device, using non-invasive tools (e.g., dissolved gas sensors, online mass spectrometry) to automate real-time measurements, thus permitting unsupervised experiments to search for optimal growth conditions, to monitor physiological responses to perturbations, as well as to quantitate photophysiological parameters using an in situ light-saturation response routine.

  8. LED-Induced Fluorescence System for Tea Classification and Quality Assessment

    E-Print Network [OSTI]

    Dong, Yongjiang; Mei, Liang; Feng, Chao; Yan, Chunsheng; He, Sailing

    2013-01-01

    A fluorescence system is developed by using several light emitting diodes (LEDs) with different wavelengths as excitation light sources. The fluorescence detection head consists of multi LED light sources and a multimode fiber for fluorescence collection, where the LEDs and the corresponding filters can be easily chosen to get appropriate excitation wavelengths for different applications. By analyzing fluorescence spectra with the principal component analysis method, the system is utilized in the classification of four types of green tea beverages and two types of black tea beverages. Qualities of the Xihu Longjing tea leaves of different grades, as well as the corresponding liquid tea samples, are studied to further investigate the ability and application of the system in the evaluation of classification/quality of tea and other foods.

  9. Characterization of failure modes in deep UV and deep green LEDs utilizing advanced semiconductor localization techniques.

    SciTech Connect (OSTI)

    Tangyunyong, Paiboon; Miller, Mary A.; Cole, Edward Isaac, Jr.

    2012-03-01

    We present the results of a two-year early career LDRD that focused on defect localization in deep green and deep ultraviolet (UV) light-emitting diodes (LEDs). We describe the laser-based techniques (TIVA/LIVA) used to localize the defects and interpret data acquired. We also describe a defect screening method based on a quick electrical measurement to determine whether defects should be present in the LEDs. We then describe the stress conditions that caused the devices to fail and how the TIVA/LIVA techniques were used to monitor the defect signals as the devices degraded and failed. We also describe the correlation between the initial defects and final degraded or failed state of the devices. Finally we show characterization results of the devices in the failed conditions and present preliminary theories as to why the devices failed for both the InGaN (green) and AlGaN (UV) LEDs.

  10. Dual LED/incandescent security fixture

    DOE Patents [OSTI]

    Gauna, Kevin Wayne

    2005-06-21

    A dual LED and incandescent security lighting system uses a hybrid approach to LED illumination. It combines an ambient LED illuminator with a standard incandescent lamp on a motion control sensor. The LED illuminator will activate with the onset of darkness (daylight control) and typically remain on during the course of the night ("always on"). The LED illumination, typically amber, is sufficient to provide low to moderate level lighting coverage to the wall and ground area adjacent to and under the fixture. The incandescent lamp is integrated with a motion control circuit and sensor. When movement in the field of view is detected (after darkness), the incandescent lamp is switched on, providing an increased level of illumination to the area. Instead of an "always on" LED illuminator, the LEDs may also be switched off when the incandescent lamp is switched on.

  11. Variable delivery, fixed displacement pump

    DOE Patents [OSTI]

    Sommars, Mark F. (Sparland, IL)

    2001-01-01

    A variable delivery, fixed displacement pump comprises a plurality of pistons reciprocated within corresponding cylinders in a cylinder block. The pistons are reciprocated by rotation of a fixed angle swash plate connected to the pistons. The pistons and cylinders cooperate to define a plurality of fluid compression chambers each have a delivery outlet. A vent port is provided from each fluid compression chamber to vent fluid therefrom during at least a portion of the reciprocal stroke of the piston. Each piston and cylinder combination cooperates to close the associated vent port during another portion of the reciprocal stroke so that fluid is then pumped through the associated delivery outlet. The delivery rate of the pump is varied by adjusting the axial position of the swash plate relative to the cylinder block, which varies the duration of the piston stroke during which the vent port is closed.

  12. Displacement of crude oil by carbon dioxide 

    E-Print Network [OSTI]

    Omole, Olusegun

    1980-01-01

    DISPLACEMENT OF CRUDE OIL BY CARBON DIOXIDE A Thesis by OLUSEGUN OMOLE Submitted to the Graduate College of Texas ASM University in part';al fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1980 Major Subject...: Petroleum Engineering DISPLACEMENT OF CRUDE OIL BY CARBON DIOXIDE A Thesis by OLUSEGUN OMOLE Approved as to style and content by: hairman of Committee / (Member (Member (Member (Hea o Depart ent December 1980 ABSTRACT Displacement of Crude Oil...

  13. Displacing Natural Gas Consumption and Lowering Emissions

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

    for Refinery and Chemical Plant Process Heaters ADVANCED MANUFACTURING OFFICE Displacing Natural Gas Consumption and Lowering Emissions By enabling process heaters to utilize...

  14. Thermal And Mechanical Analysis of High-power Light-emitting Diodes with Ceramic Packages

    E-Print Network [OSTI]

    J. Hu; L. Yang; M. -W. Shin

    2008-01-07

    In this paper we present the thermal and mechanical analysis of high-power light-emitting diodes (LEDs) with ceramic packages. Transient thermal measurements and thermo-mechanical simulation were performed to study the thermal and mechanical characteristics of ceramic packages. Thermal resistance from the junction to the ambient was decreased from 76.1 oC/W to 45.3 oC/W by replacing plastic mould to ceramic mould for LED packages. Higher level of thermo-mechanical stresses in the chip were found for LEDs with ceramic packages despite of less mismatching coefficients of thermal expansion comparing with plastic packages. The results suggest that the thermal performance of LEDs can be improved by using ceramic packages, but the mounting process of the high power LEDs with ceramic packages is critically important and should be in charge of delaminating interface layers in the packages.

  15. System Reliability for LED-Based Products

    SciTech Connect (OSTI)

    Davis, J Lynn; Mills, Karmann; Lamvik, Michael; Yaga, Robert; Shepherd, Sarah D; Bittle, James; Baldasaro, Nick; Solano, Eric; Bobashev, Georgiy; Johnson, Cortina; Evans, Amy

    2014-04-07

    Results from accelerated life tests (ALT) on mass-produced commercially available 6” downlights are reported along with results from commercial LEDs. The luminaires capture many of the design features found in modern luminaires. In general, a systems perspective is required to understand the reliability of these devices since LED failure is rare. In contrast, components such as drivers, lenses, and reflector are more likely to impact luminaire reliability than LEDs.

  16. LED Street Lighting Conversion Workshop Presentations

    Broader source: Energy.gov [DOE]

    This page provides links to the presentations given at the National League of Cities Mobile Workshop, LED Street Lighting Conversion: Saving Your Community Money, While Improving Public Safety,...

  17. A Practical Primer to LED Technology

    Energy Savers [EERE]

    ssl.energy.gov 2011 LED Transformations, LLC 60 Acknowledgements Support for the development and presentation of this educational seminar was provided by the US Department of...

  18. Challenges in LED Research and Development

    Broader source: Energy.gov [DOE]

    View the video about LED lighting technology, where it is headed, and the DOE’s role in its continued R&D.

  19. LED Outdoor Area Lighting Fact Sheet

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

    Outdoor Area Lighting LED technology is rapidly becoming competitive with high-intensity discharge light sources for outdoor area lighting. This document reviews the major design...

  20. Solid State Lighting LED Manufacturing Roundtable Summary

    SciTech Connect (OSTI)

    None

    2010-03-31

    Summary of a meeting of LED experts to develop proposed priority tasks for the Manufacturing R&D initiative, including task descriptions, discussion points, recommendations, and presentation highlights.

  1. Municipal Consortium LED Street Lighting Workshop Presentations...

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

    Controls Norma Isahakian, City of Los Angeles Bureau of Street Lighting San Jose's "Smart" LED Streetlights: Controlled Amy Olay, City of San Jose Adaptive Lighting Controls...

  2. Municipal Consortium LED Street Lighting Workshop Presentations...

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

    Boston, MA Municipal Consortium LED Street Lighting Workshop Presentations and Materials-Boston, MA This page provides links to the presentations given at the DOE Municipal...

  3. Municipal Consortium LED Street Lighting Workshop Presentations...

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

    Dallas, TX Municipal Consortium LED Street Lighting Workshop Presentations and Materials-Dallas, TX This page provides links to the presentations given at the DOE Municipal...

  4. Low Emission Development Strategies (LEDS): Technical, Institutional...

    Open Energy Info (EERE)

    Low Emission Development Strategies (LEDS): Technical, Institutional and Policy Lessons Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Low Emission Development...

  5. LED Replacements for Linear Fluorescent Lamps Webcast

    Broader source: Energy.gov [DOE]

    In this June 20, 2011 webcast on LED products marketed as replacements for linear fluorescent lamps, Jason Tuenge of the Pacific Northwest National Laboratory (PNNL) discussed current Lighting...

  6. LED Linear Lamps and Troffer Lighting

    Broader source: Energy.gov [DOE]

    The CALiPER program performed a series of investigations on linear LED lamps. Each report in the series covers the performance of up to 31 linear LED lamps, which were purchased in late 2012 or 2013. The first report focuses on bare lamp performance of LED T8 replacement lamps and subsequent reports examine performance in various troffers, as well as cost-effectiveness. There is also a concise guidance document that describes the findings of the Series 21 studies and provides practical advice to manufacturers, specifiers, and consumers (Report 21.4: Summary of Linear (T8) LED Lamp Testing , 5 pages, June 2014).

  7. Note: A portable, light-emitting diode-based ruby fluorescence spectrometer for high-pressure calibration

    SciTech Connect (OSTI)

    Feng Yejun [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2011-04-15

    Ruby (Al{sub 2}O{sub 3}, with {approx}0.5 wt. % Cr doping) is one of the most widely used manometers at the giga-Pascal scale. Traditionally, its fluorescence is excited with intense laser sources. Here, I present a simple, robust, and portable design that employs light-emitting diodes (LEDs) instead. This LED-based system is safer in comparison with laser-based ones.

  8. Displacement Hull Catamaran July 26, 2006

    E-Print Network [OSTI]

    Wood, Stephen L.

    Systems for the funds given during the project, as well as Structural Composites Inc. of West Melbourne was to design and build a prototype displacement catamaran vessel to the scale of the existing planing catamaran was to test the displacement catamaran hull and acquire meaningful performance data using multi

  9. Some considerations of the design of displacers for Ringbom Stirling engines

    SciTech Connect (OSTI)

    Fauvel, O.R.; Kentfield, J.A.C.; Walker, G.

    1984-08-01

    The Ringbom Stirling engine is a hybrid of the kinematic Stirling engine having shaft output power and variable speed and of the free piston engine in which the components are driven by changes in working space pressure. Experiments with Ringbom Stirling engines have led to the suspicion that the 'weak link' of the engine is the free displacer. This paper examines some of the factors which must be addressed in the design of displacers for these engines with reference to the thermal, pressure, and dynamical considerations.

  10. Journal of Light Emitting Diodes Vol 2 N0 1, April 2010 1 Abstract--Semiconductor nanocrystal quantum dots (NQD)

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    of energy saving and carbon dioxide emission reduction [1]. By extrapolating from current rates convertors integrated on light-emitting diodes (LEDs). The use of nonradiative energy transfer, also known as Förster-type resonance energy transfer (FRET), in such NQD nanophosphors provides additional benefits

  11. Megahertz organic/polymer diodes

    DOE Patents [OSTI]

    Katz, Howard Edan; Sun, Jia; Pal, Nath Bhola

    2012-12-11

    Featured is an organic/polymer diode having a first layer composed essentially of one of an organic semiconductor material or a polymeric semiconductor material and a second layer formed on the first layer and being electrically coupled to the first layer such that current flows through the layers in one direction when a voltage is applied in one direction. The second layer is essentially composed of a material whose characteristics and properties are such that when formed on the first layer, the diode is capable of high frequency rectifications on the order of megahertz rectifications such as for example rectifications at one of above 100KHz, 500KhZ, IMHz, or 10 MHz. In further embodiments, the layers are arranged so as to be exposed to atmosphere.

  12. Solving the 'Green Gap' in LED Technology

    Broader source: Energy.gov [DOE]

    One long-standing high-priority research area for DOE is to increase the efficiency of deep green LEDs. Although most products today use phosphor conversion (PC) to produce white light from a blue LED, having a good green source could lead to color-mixed white sources that would avoid the losses associated with the PC approach.

  13. 100 LPW 800 Lm Warm White LED

    SciTech Connect (OSTI)

    Decai Sun

    2010-10-31

    An illumination grade warm white (WW) LED, having correlated color temperature (CCT) between 2800 K and 3500K and capable of producing 800 lm output at 100 lm/W, has been developed in this program. The high power WW LED is an ideal source for use as replacement for incandescent, and Halogen reflector and general purpose lamps of similar lumen value. Over the two year period, we have made following accomplishments: developed a high power warm white LED product and made over 50% improvements in light output and efficacy. The new high power WW LED product is a die on ceramic surface mountable LED package. It has four 1x1 mm{sup 2} InGaN pump dice flip chip attached to a ceramic submount in 2x2 array, covered by warm white phosphor ceramic platelets called Lumiramicâ?¢ and an overmolded silicone lens encapsulating the LED array. The performance goal was achieved through breakthroughs in following key areas: (1) High efficiency pump LED development through pump LED active region design and epi growth quality improvement (funded by internal programs). (2) Increase in injection efficiency (IE) represented by reduction in forward voltage (V{sub f}) through the improvement of the silver-based p-contact and a reduction in spreading resistance. The injection efficiency was increased from 80% at the start of the program to 96% at the end of the program at 700 mA/mm{sup 2}. (3) Improvement in thermal design as represented by reduction in thermal resistance from junction to case, through improvement of the die to submount connection in the thin film flip chip (TFFC) LED and choosing the submount material of high thermal conductivity. A thermal resistance of 1.72 K/W was demonstrated for the high power LED package. (4) Improvement in extraction efficiency from the LED package through improvement of InGaN die level and package level optical extraction efficiency improvement. (5) Improvement in phosphor system efficiency by improving the lumen equivalent (LE) and phosphor package efficiency (PPE) through improvement in phosphor-package interactions. Another achievement in the development of the phosphor integration technology is the demonstration of tight color control. The high power WW LED product developed has been proven to have good reliability. The manufacturing of the product will be done in Philips Lumiledsâ?? LUXEON Rebel production line which has produced billions of high power LEDs. The first high power WW LED product will be released to the market in 2011.

  14. Long-term Testing Results for the 2008 Installation of LED Luminaires at the I-35 West Bridge in Minneapolis

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Davis, Robert G.

    2014-09-30

    This document reports the long-term testing results from an extended GATEWAY project that was first reported in “Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at the I-35W Bridge, in Minneapolis, MN,” August 2009. That original report presented the results of lighting the newly reconstructed I 35W Bridge using LEDs in place of conventional high-pressure sodium (HPS) roadway luminaires, comparing energy use and illuminance levels with a simulated baseline condition. That installation was an early stage implementation of LED lighting and remains one of the oldest installations in continued operation today. This document provides an update of the LED system’s performance since its installation in September 2008.

  15. Physics and Applications of Laser Diode Chaos

    E-Print Network [OSTI]

    Sciamanna, Marc

    2015-01-01

    An overview of chaos in laser diodes is provided which surveys experimental achievements in the area and explains the theory behind the phenomenon. The fundamental physics underpinning this behaviour and also the opportunities for harnessing laser diode chaos for potential applications are discussed. The availability and ease of operation of laser diodes, in a wide range of configurations, make them a convenient test-bed for exploring basic aspects of nonlinear and chaotic dynamics. It also makes them attractive for practical tasks, such as chaos-based secure communications and random number generation. Avenues for future research and development of chaotic laser diodes are also identified.

  16. Physics and Applications of Laser Diode Chaos

    E-Print Network [OSTI]

    Marc Sciamanna; K. Alan Shore

    2015-07-31

    An overview of chaos in laser diodes is provided which surveys experimental achievements in the area and explains the theory behind the phenomenon. The fundamental physics underpinning this behaviour and also the opportunities for harnessing laser diode chaos for potential applications are discussed. The availability and ease of operation of laser diodes, in a wide range of configurations, make them a convenient test-bed for exploring basic aspects of nonlinear and chaotic dynamics. It also makes them attractive for practical tasks, such as chaos-based secure communications and random number generation. Avenues for future research and development of chaotic laser diodes are also identified.

  17. High Power UV LED Industrial Curing Systems

    SciTech Connect (OSTI)

    Karlicek, Robert, F., Jr; Sargent, Robert

    2012-05-14

    UV curing is a green technology that is largely underutilized because UV radiation sources like Hg Lamps are unreliable and difficult to use. High Power UV LEDs are now efficient enough to replace Hg Lamps, and offer significantly improved performance relative to Hg Lamps. In this study, a modular, scalable high power UV LED curing system was designed and tested, performing well in industrial coating evaluations. In order to achieve mechanical form factors similar to commercial Hg Lamp systems, a new patent pending design was employed enabling high irradiance at long working distances. While high power UV LEDs are currently only available at longer UVA wavelengths, rapid progress on UVC LEDs and the development of new formulations designed specifically for use with UV LED sources will converge to drive more rapid adoption of UV curing technology. An assessment of the environmental impact of replacing Hg Lamp systems with UV LED systems was performed. Since UV curing is used in only a small portion of the industrial printing, painting and coating markets, the ease of use of UV LED systems should increase the use of UV curing technology. Even a small penetration of the significant number of industrial applications still using oven curing and drying will lead to significant reductions in energy consumption and reductions in the emission of green house gases and solvent emissions.

  18. Joint Visible Light Communication and Navigation via LEDs

    E-Print Network [OSTI]

    Zheng, Dongfang

    2014-01-01

    modulated automobile LED lightings to estimate the vehiclemodulates the automobile LED lighting - either taillights orpositioning using lighting led and image sensor. In Computer

  19. Getting Ready for LEDs: LED Lighting Video Series Explains the Basics

    Broader source: Energy.gov [DOE]

    A new video series from ElectricTV.net explains the changes and opportunities offered by LED lighting.

  20. Internal efficiency of InGaN light-emitting diodes: Beyond a quasiequilibrium model

    SciTech Connect (OSTI)

    Chow, Weng W.; Crawford, Mary H.; Tsao, Jeffrey Y.; Kneissl, Michael

    2010-01-01

    We propose a model to better investigate InGaN light-emitting diode (LED) internal efficiency by extending beyond the usual total carrier density rate equation approach. To illustrate its capability, the model is applied to study intrinsic performance differences between violet and green LEDs. The simulations show performance differences, at different current densities and temperatures, arising from variations in spontaneous emission and heat loss rates. By tracking the momentum-resolved carrier populations, these rate changes are, in turn, traced to differences in bandstructure and plasma heating. The latter leads to carrier distributions that deviate from the quasiequilibrium ones at lattice temperature.

  1. High Efficiency m-plane LEDs on Low Defect Density Bulk GaN Substrates

    SciTech Connect (OSTI)

    David, Aurelien

    2012-10-15

    Solid-state lighting is a key technology for reduction of energy consumption in the US and worldwide. In principle, by replacing standard incandescent bulbs and other light sources with sources based on light-emitting diodes (LEDs), ultimate energy efficiency can be achieved. The efficiency of LEDs has improved tremendously over the past two decades, however further progress is required for solid- state lighting to reach its full potential. The ability of an LED at converting electricity to light is quantified by its internal quantum efficiency (IQE). The material of choice for visible LEDs is Gallium Nitride (GaN), which is at the basis of blue-emitting LEDs. A key factor limiting the performance of GaN LEDs is the so-called efficiency droop, whereby the IQE of the LED decreases significantly at high current density. Despite decades of research, efficiency droop remains a major issue. Since high-current operation is necessary for practical lighting applications, reducing droop is a major challenge for the scientific community and the LED industry. Our approach to solving the droop issue is the use of newly available low-defect-density bulk GaN non-polar substrates. In contrast to the standard foreign substrates (sapphire, silicon carbide, silicon) used in the industry, we have employed native bulk GaN substrates with very low defect density, thus ensuring exquisite material quality and high IQE. Whereas all commercial LEDs are grown along the c-plane crystal direction of GaN, we have used m-plane non-polar substrates; these drastically modify the physical properties of the LED and enable a reduction of droop. With this approach, we have demonstrated very high IQE performance and low droop. Our results focused on violet and blue LEDs. For these, we have demonstrated very high peak IQEs and current droops of 6% and 10% respectively (up to a high current density of 200A.cm-2). All these results were obtained under electrical operation. These high IQE and low droop values are in line with the program’s milestones. They demonstrate that bulk non-polar GaN substrates represent a disruptive technology for LED performance. Application of this technology to real-world products is feasible, provided that the cost of GaN substrates is compatible with the market’s requirement.

  2. Temperature-dependent light-output characteristics of GaInN light-emitting diodes with different dislocation densities

    SciTech Connect (OSTI)

    Chhajed, Sameer; Cho, Jaehee; Schubert, E. Fred; Kim, Jong Kyu; Koleske, Daniel D.; Crawford, Mary H.

    2011-01-01

    We have experimentally investigated the temperature dependence of optical-output power of light-emitting diodes (LEDs) with different threading dislocation densities (TDDs) to assess the influence of the TDD on the temperature stability of LEDs. Whereas the LED with high TDD shows a 64% decrease in optical-output power when the ambient temperature increases from 20 to 150?°C, the LED with low TDD shows only a 54% decrease. The temperature dependence of the optical-output power and current dependence of the characteristic temperature T{sub ch} of LEDs shows that short radiative recombination lifetime and low TDDs are essential to obtain LED characteristics that are tolerant of high temperatures.

  3. Light-Emitting Diodes on Semipolar Bulk Gallium Nitride Substrate...

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

    Light-Emitting Diodes on Semipolar Bulk Gallium Nitride Substrate Light-Emitting Diodes on Semipolar Bulk Gallium Nitride Substrate Presenter: Arpan Chakraborty, Soraa Inc. This...

  4. Heat diode effect and negative differential thermal conductance...

    Office of Scientific and Technical Information (OSTI)

    Heat diode effect and negative differential thermal conductance across nanoscale metal-dielectric interfaces Citation Details In-Document Search Title: Heat diode effect and...

  5. Advanced method for increasing the efficiency of white light quantum dot LEDs

    SciTech Connect (OSTI)

    Duty, Chad E [ORNL; Bennett, Charlee J C [ORNL; Sabau, Adrian S [ORNL; Jellison Jr, Gerald Earle [ORNL; Boudreaux, Philip R [ORNL; Walker, Steven C [ORNL; Ott, Ronald D [ORNL

    2011-01-01

    Covering a light-emitting diode (LED) with quantum dots (QDs) can produce a broad spectrum of white light. However, current techniques for applying QDs to LEDs suffer from a high density of defects and a non-uniform distribution of QDs, which, respectively, diminish the efficiency and quality of emitted light. Oak Ridge National Laboratory (ORNL) has the unique capability to thermally anneal QD structures at extremely high power densities for very short durations. This process, called pulse thermal processing (PTP), reduces the number of point defects while maintaining the size and shape of the original QD nanostructure. Therefore, the efficiency of the QD wavelength conversion layer is improved without altering the emission spectrum defined by the size distribution of theQD nanoparticles. The current research uses a thermal model to predict annealing temperatures during PTP and demonstrates up to a 300% increase in photoluminescence for QDs on passive substrates.

  6. Characterising and Testing Deep UV LEDs for Use in Space Applications

    E-Print Network [OSTI]

    Hollington, D; Sumner, T J; Wass, P J

    2015-01-01

    Deep ultraviolet (DUV) light sources are used to neutralise isolated test masses in highly sensitive space-based gravitational experiments. An example is the LISA Pathfinder charge management system, which uses low-pressure mercury lamps. A future gravitational-wave observatory such as eLISA will use UV light-emitting diodes (UV LEDs), which offer numerous advantages over traditional discharge lamps. Such devices have limited space heritage but are are now available from a number of commercial suppliers. Here we report on a test campaign that was carried out to quantify the general properties of three types of commercially available UV LEDs and demonstrate their suitability for use in space. Testing included general electrical and UV output measurements, spectral stability, pulsed performance, temperature dependence as well as thermal vacuum, radiation and vibration survivability.

  7. Scale model studies of displacement ventilation

    E-Print Network [OSTI]

    Okutan, Galip Mehmet

    1995-01-01

    Displacement ventilation is an air conditioning method that provides conditioned air to indoor environments with the goal to improve air quality while reducing energy consumption. This study investigates the performance ...

  8. Management of Internal Displacement in Nigeria

    E-Print Network [OSTI]

    Olagunju, Olajide

    This research examined the management of IDP’s (internally displaced persons) in Nigeria based on the February/May 2000 communal conflict at Kaduna, Northern Nigeria, as an example and a focus for the study. The research ...

  9. Displacement speeds in turbulent premixed flame simulations

    E-Print Network [OSTI]

    Day, Marcus S.; Shepherd, Ian G.; Bell, J.; Grcar, Joseph F.; Lijewski, Michael J.

    2008-01-01

    elds for reaction rate progress and ?uid velocity. Thefor the velocity ?elds and the scalar measure of reactionvelocity and the temperature. To evaluate the displacement speed we de?ne a reaction

  10. LED Color Stability: 10 Important Questions

    Broader source: Energy.gov [DOE]

    This April 15, 2014 webinar examined the causes of color shift, and took a look at existing metrics used to describe color shift/color stability in LED lighting. The lumen maintenance lifetime of...

  11. Text-Alternative Version LED Lighting Forecast

    Broader source: Energy.gov [DOE]

    The DOE report Energy Savings Forecast of Solid-State Lighting in General Illumination Applications estimates the energy savings of LED white-light sources over the analysis period of 2013 to 2030....

  12. LED Essentials- Technology, Applications, Advantages, Disadvantages

    Broader source: Energy.gov [DOE]

    On October 11, 2007, Kevin Dowling, VP of Innovation for Philips Solid-State Lighting Solutions, presented a broad introduction to LED technology, and discussed the technology status, advantages...

  13. All inorganic colloidal quantum dot LEDs

    E-Print Network [OSTI]

    Wood, Vanessa Claire

    2007-01-01

    This thesis presents the first colloidal quantum dot light emitting devices (QD-LEDs) with metal oxide charge transport layers. Colloidally synthesized quantum dots (QDs) have shown promise as the active material in ...

  14. SPECIFYING LED COLOR-TUNABLE PRODUCTS

    Broader source: Energy.gov [DOE]

    Specifying LED color-tunable luminaires is dependent on being able to make accurate comparisons between products. Yet reporting performance values for color-tunable products is much more...

  15. DOE Hosts LED Industry Standards Workshop

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy hosted an LED Industry Standards Workshop on March 1, 2006 in Washington, D.C. The Workshop provided a forum to encourage greater cooperation and coordination among...

  16. Sidewall passivation for InGaN/GaN nanopillar light emitting diodes

    SciTech Connect (OSTI)

    Choi, Won Hyuck; Abraham, Michael; Yu, Shih-Ying [Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); You, Guanjun; Liu, Jie; Wang, Li; Xu, Jian, E-mail: jianxu@engr.psu.edu [Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Mohney, Suzanne E., E-mail: mohney@ems.psu.edu [Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2014-07-07

    We studied the effect of sidewall passivation on InGaN/GaN multiquantum well-based nanopillar light emitting diode (LED) performance. In this research, the effects of varying etch rate, KOH treatment, and sulfur passivation were studied for reducing nanopillar sidewall damage and improving device efficiency. Nanopillars prepared under optimal etching conditions showed higher photoluminescence intensity compared with starting planar epilayers. Furthermore, nanopillar LEDs with and without sulfur passivation were compared through electrical and optical characterization. Suppressed leakage current under reverse bias and four times higher electroluminescence (EL) intensity were observed for passivated nanopillar LEDs compared with unpassivated nanopillar LEDs. The suppressed leakage current and EL intensity enhancement reflect the reduction of non-radiative recombination at the nanopillar sidewalls. In addition, the effect of sulfur passivation was found to be very stable, and further insight into its mechanism was gained through transmission electron microscopy.

  17. LED ADOPTION REPORT | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT PDF icon Report:

  18. LED MR16 Lamps | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT PDFLED

  19. LED MR16 Lamps | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT PDFLEDLED MR16

  20. LED Market Adoption: Status and Trends

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT PDFLEDLED

  1. LED PAR38 Lamps | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT

  2. LED Roundtable Reports | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORTLEDLED Roundtable

  3. It's 2015: Should All Your Sockets be Filled with LEDs?

    Energy Savers [EERE]

    - mid-power LEDs on PCb used in 2x4 troffers 4 LED Modules and Light Engines GE Infusion Philips Fortimo Osram PrevaLED 5 LEDs: A New Light Source for Everything * Outdoor...

  4. A portable time-domain LED fluorimeter for nanosecond fluorescence lifetime measurements

    SciTech Connect (OSTI)

    Wang, Hongtao; Salthouse, Christopher D., E-mail: salthouse@ecs.umass.edu [Electrical and Computer Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Qi, Ying; Mountziaris, T. J. [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States) [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Chemical Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States)

    2014-05-15

    Fluorescence lifetime measurements are becoming increasingly important in chemical and biological research. Time-domain lifetime measurements offer fluorescence multiplexing and improved handling of interferers compared with the frequency-domain technique. In this paper, an all solid-state, filterless, and highly portable light-emitting-diode based time-domain fluorimeter (LED TDF) is reported for the measurement of nanosecond fluorescence lifetimes. LED based excitation provides more wavelengths options compared to laser diode based excitation, but the excitation is less effective due to the uncollimated beam, less optical power, and longer latency in state transition. Pulse triggering and pre-bias techniques were implemented in our LED TDF to improve the peak optical power to over 100 mW. The proposed pulsing circuit achieved an excitation light fall time of less than 2 ns. Electrical resetting technique realized a time-gated photo-detector to remove the interference of the excitation light with fluorescence. These techniques allow the LED fluorimeter to accurately measure the fluorescence lifetime of fluorescein down to concentration of 0.5 ?M. In addition, all filters required in traditional instruments are eliminated for the non-attenuated excitation/emission light power. These achievements make the reported device attractive to biochemical laboratories seeking for highly portable lifetime detection devices for developing sensors based on fluorescence lifetime changes. The device was initially validated by measuring the lifetimes of three commercial fluorophores and comparing them with reported lifetime data. It was subsequently used to characterize a ZnSe quantum dot based DNA sensor.

  5. LEDS GP Success Story: Fostering Coordinated LEDS Support in Kenya (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-03-01

    The LEDS Global Partnership (LEDS GP) strives to advance climate-resilient, low-emission development through catalyzing collaboration, information exchange, and action on the ground. The Government of Kenya is a key LEDS GP member and offers an inspiring example of how LEDS GP is having an impact globally. The 2012 LEDS Collaboration in Action workshop in London provided an interactive space for members to share experiences on cross-ministerial LEDS leadership and to learn about concrete development impacts of LEDS around the world. Inspired by these stories, the Kenya's Ministry of State for Planning, National Development and Vision 2030 (MPND) began to collaborate closely with the Ministry of Environment and Mineral Resources to create strong links between climate change action and development in the country, culminating in the integration of Kenya's National Climate Change Action Plan and the country's Medium Term Development Plan.

  6. Quantum-dot light-emitting diodes utilizing CdSe/ZnS nanocrystals embedded in TiO{sub 2} thin film

    SciTech Connect (OSTI)

    Kang, Seung-Hee; Kumar, Ch. Kiran; Kim, Eui-Tae; Lee, Zonghoon; Kim, Kyung-Hyun; Huh, Chul

    2008-11-10

    Quantum-dot (QD) light-emitting diodes (LEDs) are demonstrated on Si wafers by embedding core-shell CdSe/ZnS nanocrystals in TiO{sub 2} thin films via plasma-enhanced metallorganic chemical vapor deposition. The n-TiO{sub 2}/QDs/p-Si LED devices show typical p-n diode current-voltage and efficient electroluminescence characteristics, which are critically affected by the removal of QD surface ligands. The TiO{sub 2}/QDs/Si system we presented can offer promising Si-based optoelectronic and electronic device applications utilizing numerous nanocrystals synthesized by colloidal solution chemistry.

  7. Pittsburgh LED Street Lighting Research Project Performance Criteria

    Office of Energy Efficiency and Renewable Energy (EERE)

    A Pittsburgh LED Street Lighting Research Project document on Technical and Aesthetic Performance for Business District LED Lighting.

  8. Light source comprising a common substrate, a first led device and a second led device

    DOE Patents [OSTI]

    Choong, Vi-En (Carlsbad, CA)

    2010-02-23

    At least one stacked organic or polymeric light emitting diode (PLEDs) devices to comprise a light source is disclosed. At least one of the PLEDs includes a patterned cathode which has regions which transmit light. The patterned cathodes enable light emission from the PLEDs to combine together. The light source may be top or bottom emitting or both.

  9. A STOCHASTIC METHOD FOR MODELING FLUID DISPLACEMENT IN PETROLEUM RESERVOIRS

    E-Print Network [OSTI]

    Anderson, C.

    2011-01-01

    FLUID DISPLACEMENT IN PETROLEUM RESERVOIRS C. Anderson andFLUID DISPLACEMENT IN PETROLEUM RESERVOIRS C. Anderson andachieve optimal recovery of petroleum from a reservoir, it

  10. Laser diode package with enhanced cooling

    DOE Patents [OSTI]

    Deri, Robert J. (Pleasanton, CA); Kotovsky, Jack (Oakland, CA); Spadaccini, Christopher M. (Oakland, CA)

    2012-06-12

    A laser diode package assembly includes a reservoir filled with a fusible metal in close proximity to a laser diode. The fusible metal absorbs heat from the laser diode and undergoes a phase change from solid to liquid during the operation of the laser. The metal absorbs heat during the phase transition. Once the laser diode is turned off, the liquid metal cools off and resolidifies. The reservoir is designed such that that the liquid metal does not leave the reservoir even when in liquid state. The laser diode assembly further includes a lid with one or more fin structures that extend into the reservoir and are in contact with the metal in the reservoir.

  11. Laser diode package with enhanced cooling

    DOE Patents [OSTI]

    Deri, Robert J. (Pleasanton, CA); Kotovsky, Jack (Oakland, CA); Spadaccini, Christopher M. (Oakland, CA)

    2011-09-13

    A laser diode package assembly includes a reservoir filled with a fusible metal in close proximity to a laser diode. The fusible metal absorbs heat from the laser diode and undergoes a phase change from solid to liquid during the operation of the laser. The metal absorbs heat during the phase transition. Once the laser diode is turned off, the liquid metal cools off and resolidifies. The reservoir is designed such that that the liquid metal does not leave the reservoir even when in liquid state. The laser diode assembly further includes a lid with one or more fin structures that extend into the reservoir and are in contact with the metal in the reservoir.

  12. Laser diode package with enhanced cooling

    DOE Patents [OSTI]

    Deri, Robert J.; Kotovsky, Jack; Spadaccini, Christopher M.

    2012-06-26

    A laser diode package assembly includes a reservoir filled with a fusible metal in close proximity to a laser diode. The fusible metal absorbs heat from the laser diode and undergoes a phase change from solid to liquid during the operation of the laser. The metal absorbs heat during the phase transition. Once the laser diode is turned off, the liquid metal cools off and resolidifies. The reservoir is designed such that that the liquid metal does not leave the reservoir even when in liquid state. The laser diode assembly further includes a lid with one or more fin structures that extend into the reservoir and are in contact with the metal in the reservoir.

  13. A hole accelerator for InGaN/GaN light-emitting diodes Zi-Hui Zhang, Wei Liu, Swee Tiam Tan, Yun Ji, Liancheng Wang, Binbin Zhu, Yiping Zhang, Shunpeng Lu,

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    GaN/GaN light-emitting diodes (LEDs) has been significantly limited by the insufficient hole injection, the effectiveness of the hole ac- celerator is experimentally shown through achieving improved optical output power and reduced efficiency droop for the proposed InGaN/GaN LED. VC 2014 AIP Publishing LLC. [http://dx.doi.org/10

  14. Influence of n-type versus p-type AlGaN electron-blocking layer on InGaN/GaN multiple quantum wells light-emitting diodes

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    to be further improved in order for the high- power LEDs to penetrate into the consumer market of gen- eral to higher optical output power and external quantum efficiency, compared to the devices with p-AlGaN EBLGaN/GaN based light-emitting diodes (LEDs) possess unique advantages including high energy conversion effi

  15. InGaN/GaN light-emitting diode with a polarization tunnel junction Zi-Hui Zhang, Swee Tiam Tan, Zabu Kyaw, Yun Ji, Wei Liu et al.

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    to the enhanced optical output power and external quantum efficiency. Compared to the reference InGaN/GaN LEDs; accepted 29 April 2013; published online 15 May 2013) We report InGaN/GaN light-emitting diodes (LED have been devoted to boosting the optical output power and enhancing the external quantum efficiency

  16. High-power LEDs based on InGaAsP/InP heterostructures

    SciTech Connect (OSTI)

    Rakovics, V. [Hungarian Academy of Sciences, Institute of Technical Physics and Materials Science, Research Centre for Natural Sciences (Hungary); Imenkov, A. N.; Sherstnev, V. V.; Serebrennikova, O. Yu.; Il’inskaya, N. D.; Yakovlev, Yu. P., E-mail: Yak@iropt1.ioffe.ru [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

    2014-12-15

    High-power light-emitting diodes (LEDs) with mesa diameters of 100, 200, and 300 ?m are developed on the basis of InGaAsP/InP heterostructures. The mesas are close in shape to a truncated cone with a generatrix inclination angle of ?45° in the vicinity of the active region of the LED, with a ring etched around the mesa serving as a reflector. The emission spectra and directivity patterns of these LEDs are studied in a wide range of current densities and it is shown that radiative recombination is dominant to a current density of ?5000 A/cm{sup 2}, which makes these structures promising for the development of high-power LEDs. An emission power of ?14 mW is obtained in the continuous-wave mode (I = 0.2 A, ? = 1.1 ?m), and that of 77 mW, in the pulsed mode (I = 2 A, ? = 1.1 ?m), which corresponds to external quantum efficiencies of 6.2 and 3.4%, respectively.

  17. Lab 4--Signal Processing III: Diodes PHYS 309 Name

    E-Print Network [OSTI]

    Herman, Rhett

    Lab 4--Signal Processing III: Diodes PHYS 309 Name: A. Introduction Diodes are essentially one it into . B. Basic circuits and signal processing Build the circuit shown below. Note the ground! Use a = 100 is set on "dc." Lab 4-1 #12;Lab 4--Signal Processing III: Diodes PHYS 309 Name: Now add a diode to your

  18. Displacement Echoes: Classical Decay and Quantum Freeze

    E-Print Network [OSTI]

    Cyril Petitjean; Diego V. Bevilaqua; Eric J. Heller; Philippe Jacquod

    2007-04-23

    Motivated by neutron scattering experiments, we investigate the decay of the fidelity with which a wave packet is reconstructed by a perfect time-reversal operation performed after a phase space displacement. In the semiclassical limit, we show that the decay rate is generically given by the Lyapunov exponent of the classical dynamics. For small displacements, we additionally show that, following a short-time Lyapunov decay, the decay freezes well above the ergodic value because of quantum effects. Our analytical results are corroborated by numerical simulations.

  19. Fiber-optic displacement sensor system 

    E-Print Network [OSTI]

    Cava, Norayda Nora

    1990-01-01

    FIBER-OPTIC DISPLACEMENT SENSOR SYSTEM A Thesis by NORAYDA NORA CAVA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1990 Major Subject...: Electrical Engineering FIBER-OPTIC DISPLACEMENT SENSOR SYSTEM A Thesis by NORAYDA NORA CAVA Approved as to style and content by: H nry F. Taylor (Chair of Committee) Brian Y ng (Member) Raghve n ey ( ember) Sohi Rastegar (Member) Jo owze (Head...

  20. Displacement Echoes: Classical Decay and Quantum Freeze

    SciTech Connect (OSTI)

    Petitjean, Cyril [Departement de Physique Theorique, Universite de Geneve, CH-1211 Geneva 4 (Switzerland); Bevilaqua, Diego V. [Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States); Heller, Eric J. [Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States); Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138 (United States); Jacquod, Philippe [Physics Department, University of Arizona, Tucson, Arizona 85721 (United States)

    2007-04-20

    Motivated by neutron scattering experiments, we investigate the decay of the fidelity with which a wave packet is reconstructed by a perfect time-reversal operation performed after a phase-space displacement. In the semiclassical limit, we show that the decay rate is generically given by the Lyapunov exponent of the classical dynamics. For small displacements, we additionally show that, following a short-time Lyapunov decay, the decay freezes well above the ergodic value because of quantum effects. Our analytical results are corroborated by numerical simulations.

  1. Fusion Energy An Industry-Led Initiative

    E-Print Network [OSTI]

    business not big science InternationalCompetitivenessissue - $26T/yr energy market with $300B/yr futureFusion Energy An Industry-Led Initiative September 10,1993 ATeam Effort TRW General Dynamics;Energy Supply and Needs Global per capita energy usage Global Per Capita energy usage will increase even

  2. LED Lighting in a Performing Arts Building

    SciTech Connect (OSTI)

    Miller, N. J.; Kaye, S. M.; Coleman, P. M.; Wilkerson, A. M.; Perrin, T. E.; Sullivan, G. P.

    2014-07-31

    At the University of Florida in Gainesville, the DOE Solid-State Lighting GATEWAY program evaluated LED architectural and theatrical lighting in four academic/performance-related spaces within the Nadine McGuire Theatre + Dance Pavilion. Due to a wise choice of products and luminaire light distributions, the change brought significant quality improvements including improved controllability and color.

  3. LED structure with enhanced mirror reflectivity

    DOE Patents [OSTI]

    Bergmann, Michael; Donofrio, Matthew; Heikman, Sten; Schneider, Kevin S; Haberern, Kevin W; Edmond, John A

    2014-04-01

    Embodiments of the present invention are generally related to LED chips having improved overall emission by reducing the light-absorbing effects of barrier layers adjacent mirror contacts. In one embodiment, a LED chip comprises one or more LEDs, with each LED having an active region, a first contact under the active region having a highly reflective mirror, and a barrier layer adjacent the mirror. The barrier layer is smaller than the mirror such that it does not extend beyond the periphery of the mirror. In another possible embodiment, an insulator is further provided, with the insulator adjacent the barrier layer and adjacent portions of the mirror not contacted by the active region or by the barrier layer. In yet another embodiment, a second contact is provided on the active region. In a further embodiment, the barrier layer is smaller than the mirror such that the periphery of the mirror is at least 40% free of the barrier layer, and the second contact is below the first contact and accessible from the bottom of the chip.

  4. 12RESEARCHERS Western-led creation of

    E-Print Network [OSTI]

    Denham, Graham

    delegation to Brazil, accompanied by Governor General David Johnston, in April 2012 alternative energy Next-generation renewable energy sources from wind, sun and biofuels for a greener world BRAZIL Impact / Reputation globalbrazil #12;BRAZIL Investment 12RESEARCHERS Western-led creation of Canada Visiting Chair

  5. Air Emissions and Oil Displacement Benefits

    E-Print Network [OSTI]

    McGaughey, Alan

    and the U.S. costs of oil consumption, including supply disruption risks, increases in world oil prices dueAir Emissions and Oil Displacement Benefits from Plug-in Vehicles The electrification of passenger; and (3) reduce gasoline consumption, helping to diminish dependency on imported oil. Current policy

  6. Wien's Displacement Law in Rindler Space

    E-Print Network [OSTI]

    De, Sanchari; Ghosh, Sutapa; Chakrabarty, Somenath

    2015-01-01

    In this article we have developed a formalism to obtained the modified form of Wien's displacement law when the wall of the enclosure containing a photon gas is expanding adiabatically with a uniform acceleration. We have also studied the gravitational redshift of photons inside the enclosure using the prescription of extended relativistic dynamics with an upper limit of acceleration.

  7. Coreflood experimental study of steam displacement 

    E-Print Network [OSTI]

    Cerutti, Andres Enrique

    1997-01-01

    The main objective of this study was to verify experimentally whether or not a Buckley-Leverett shock front exists when steam displaces oil in a porous medium, as assumed in the Aydelotte-Pope steamflood predictive model. Experiments were conducted...

  8. Low-Cost Illumination-Grade LEDs

    SciTech Connect (OSTI)

    Epler, John

    2013-08-31

    Solid State Lighting is a cost-effective, energy-conserving technology serving a rapidly expand- ing multi-billion dollar market. This program was designed to accelerate this lighting revolution by reducing the manufacturing cost of Illumination-Grade LEDs. The technical strategy was to investigate growth substrate alternatives to standard planar sapphire, select the most effective and compatible option, and demonstrate a significant increase in Lumen/$ with a marketable LED. The most obvious alternate substrate, silicon, was extensively studied in the first two years of the program. The superior thermal and mechanical properties of Si were expected to improve wavelength uniformity and hence color yield in the manufacture of high-power illumination- grade LEDs. However, improvements in efficiency and epitaxy uniformity on standard c-plane sapphire diminished the advantages of switching to Si. Furthermore, the cost of sapphire decreased significantly and the cost of processing Si devices using our thin film process was higher than expected. We concluded that GaN on Si was a viable technology but not a practical option for Philips Lumileds. Therefore in 2012 and 2013, we sought and received amendments which broadened the scope to include other substrates and extended the time of execution. Proprietary engineered substrates, off-axis (non-c-plane) sapphire, and c-plane patterned sapphire substrates (PSS) were all investigated in the final 18 months of this program. Excellent epitaxy quality was achieved on all three candidates; however we eliminated engineered substrates and non-c-plane sapphire because of their higher combined cost of substrate, device fabrication and packaging. Ultimately, by fabricating a flip-chip (FC) LED based upon c-plane PSS we attained a 42% reduction in LED manufacturing cost relative to our LUXEON Rebel product (Q1-2012). Combined with a flux gain from 85 to 102 Lm, the LUXEON Q delivered a 210% increase in Lm/$ over this time period. The technology was commercialized in our LUXEON Q product in Sept., 2013. Also, the retention of the sapphire increased the robustness of the device, enabling sales of low-cost submount-free chips to lighting manufacturers. Thus, blue LED die sales were initiated in the form of a PSS-FC in February, 2013.

  9. Sustainable LED Fluorescent Light Replacement Technology

    SciTech Connect (OSTI)

    2011-06-30

    Ilumisys and the National Center for Manufacturing Sciences (NCMS) partnered on a three-year project awarded by the United States (U.S.) Department of Energy (DOE), to quantify the impacts of LED lamps, incandescent lamps and fluorescent benchmark lamps over a product lifecycle – i.e. to develop a sustainable design and manufacturing strategy that addresses product manufacturing, use, recycling and disposal scenarios for LED-based lighting. Based on the knowledge gained from extensive product tear-down studies of fluorescent and screw-in lighting products, lifecycle assessment tools, and accelerated lifecycle testing protocols, an interactive Sustainable LED Design Guide has been developed to aid architectural and lighting designers and engineers in making design decisions that consider three important environmental impacts (greenhouse gas emissions, energy use and mercury emission) across all phases of the life of an LED lighting product. Critical information developed for the lifecycle analysis and product feature comparisons is the useful life of the lighting product as well as its performance. The Design Guide is available at www.ncms.org, and was developed based on operational and durability testing of a variety of lighting products including power consumption, light output, and useful life of a lamp in order to allow a more realistic comparison of lamp designs. This report describes the main project tasks, results and innovative features of the lifecycle assessment (LCA)-based design tools, and the key considerations driving the sustainable design of LED lighting systems. The Design Guide incorporates the following three novel features for efficiently evaluating LED lighting features in value-chains: • Bill-of-Materials (BOM) Builder – Designers may import process data for each component and supply functional data for the product, including power, consumption, lumen output and expected useful life. • Environmental Impact Review – Designs are comparable across lifecycle phases, subsystems, and environmental impact category, and can be normalized to a userdefined functional unit. • Drill-down Review – These provide an indepth look at individual lamp designs with the ability to review across subsystem or lifecycle phase.

  10. A spin light emitting diode incorporating ability of electrical helicity switching

    SciTech Connect (OSTI)

    Nishizawa, N., E-mail: nishizawa@isl.titech.ac.jp; Nishibayashi, K.; Munekata, H. [Imaging Science and Engineering Laboratory, Tokyo Institute of Technology, 4259-J3-15 Nagatsuta, Midori-ku, Yokohama 226-8503 (Japan)

    2014-03-17

    Fabrication and optical characteristics of a spin light-emitting-diode (spin-LED) having dual spin-injection electrodes with anti-parallel magnetization configuration are reported. Alternating a current between the two electrodes using a computer-driven current source has led us to the observation of helicity switching of circular polarization at the frequency of 1 kHz. Neither external magnetic fields nor optical delay modulators were used. Sending dc-currents to both electrodes with appropriate ratio has resulted in continuous variation of circular polarization between the two opposite helicity, including the null polarization. These results suggest that the tested spin-LED has the feasibility of a monolithic light source whose circular polarization can be switched or continuously tuned all electrically.

  11. Is it viable to improve light output efficiency by nano-light-emitting diodes?

    SciTech Connect (OSTI)

    Wang, Chao-Hung; Huang, Yu-Wen [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China)] [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China); Wu, Shang-En [Genesis Photonics Incorporation, Tainan 70101, Taiwan (China)] [Genesis Photonics Incorporation, Tainan 70101, Taiwan (China); Liu, Chuan-Pu, E-mail: cpliu@mail.ncku.edu.tw [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China) [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China); Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan 70101, Taiwan (China); Research Center for Energy Technology and Strategy, National Cheng Kung University, Tainan 70101, Taiwan (China)

    2013-12-02

    Nanopillar arrays with InGaN/GaN multiple-quantum-disks (MQDs) are fabricated by focused-ion-beam milling with surface damage layer removed by KOH wet etching. Nano-light-emitting diodes (Nano-LEDs) made of the InGaN/GaN MQD nanopillars are found to have 19.49% less output power than that of a conventional LED. The reasons are analyzed in detail and considering their current-voltage and electroluminescence characteristics, internal quantum efficiency, external quantum efficiency, light extraction, and wall-plug efficiency. Our results suggest that nanopillar-LED can outperform if the density can be increased to 2.81?×?10{sup 9}?cm{sup ?2} with the size unchanged or the size can be increased to 854.4?nm with the density unchanged.

  12. Stacked switchable element and diode combination

    DOE Patents [OSTI]

    Branz, Howard M.; Wang, Qi

    2006-06-27

    A device (10) comprises a semiconductor diode (12) and a switchable element (14) positioned in stacked adjacent relationship so that the semiconductor diode (12) and the switchable element (14) are electrically connected in series with one another. The switchable element (14) is switchable from a low-conductance state to a high-conductance state in response to the application of a forming voltage to the switchable element (14).

  13. Bypass diode for a solar cell

    DOE Patents [OSTI]

    Rim, Seung Bum (Palo Alto, CA); Kim, Taeseok (San Jose, CA); Smith, David D. (Campbell, CA); Cousins, Peter J. (Menlo Park, CA)

    2012-03-13

    Bypass diodes for solar cells are described. In one embodiment, a bypass diode for a solar cell includes a substrate of the solar cell. A first conductive region is disposed above the substrate, the first conductive region of a first conductivity type. A second conductive region is disposed on the first conductive region, the second conductive region of a second conductivity type opposite the first conductivity type.

  14. Stacked Switchable Element and Diode Combination

    DOE Patents [OSTI]

    Branz, H. M.; Wang, Q.

    2006-06-27

    A device (10) comprises a semiconductor diode (12) and a switchable element (14) positioned in stacked adjacent relationship so that the semiconductor diode (12) and the switchable element (14) are electrically connected in series with one another. The switchable element (14) is switchable from a low-conductance state to a high-conductance state in response to the application of a forming voltage to the switchable element (14).

  15. Fundamental Studies and Development of III-N Visible LEDs for High-Power Solid-State Lighting Applications

    SciTech Connect (OSTI)

    Dupuis, Russell

    2012-02-29

    The goal of this program is to understand in a fundamental way the impact of strain, defects, polarization, and Stokes loss in relation to unique device structures upon the internal quantum efficiency (IQE) and efficiency droop (ED) of III-nitride (III-N) light-emitting diodes (LEDs) and to employ this understanding in the design and growth of high-efficiency LEDs capable of highly-reliable, high-current, high-power operation. This knowledge will be the basis for our advanced device epitaxial designs that lead to improved device performance. The primary approach we will employ is to exploit new scientific and engineering knowledge generated through the application of a set of unique advanced growth and characterization tools to develop new concepts in strain-, polarization-, and carrier dynamics-engineered and low-defect materials and device designs having reduced dislocations and improved carrier collection followed by efficient photon generation. We studied the effects of crystalline defect, polarizations, hole transport, electron-spillover, electron blocking layer, underlying layer below the multiplequantum- well active region, and developed high-efficiency and efficiency-droop-mitigated blue LEDs with a new LED epitaxial structures. We believe new LEDs developed in this program will make a breakthrough in the development of high-efficiency high-power visible III-N LEDs from violet to green spectral region.

  16. Measured Off-Grid LED Lighting System Performance

    E-Print Network [OSTI]

    Granderson, Jessica

    2009-01-01

    4 Measured Off-Grid LED Lighting System Performance Jessicapeople, the quality of LED lighting products remains acomponents of off-grid LED lighting systems (e.g. light

  17. To Bridge LEDs' Green Gap, Scientists Think Small

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

    To Bridge LEDs' Green Gap, Scientists Think Small To Bridge LEDs' Green Gap, Scientists Think Small Nanostructures Half a DNA Strand-Wide Show Promise for Efficient LEDs April 4,...

  18. LED Performance Specification Series: T8 Replacement Lamps

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

    the better fixture efficiency measured with LED T8s compared to fluorescent. Note that luminous efficacy for the LED T8 is not specified. This is because LED T8 watt- age...

  19. Room temperature thermo-electric pumping in mid-infrared light-emitting diodes Parthiban Santhanam, Duanni Huang, Rajeev J. Ram, Maxim A. Remennyi, and Boris A. Matveev

    E-Print Network [OSTI]

    Ram, Rajeev J.

    -emitting diodes (LEDs) to convert electrical power into optical power above 100% wall-plug efficiency was recently of 100% electrical-to-optical power conversion efficiency. At low forward bias, lattice heat is absorbed results. Although non-radiative recombination limits the power density available above unity efficiency

  20. LED Roadway Lighting | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICE INDUSTRIALU.S. DepartmentJeanKeyLANL SustainableRoadway Lighting LED

  1. Yellow-green emission for ETS-LEDs and lasers based on a strainedInGaP quantum well heterostructure grown on a transparent, compositionally graded AlInGaP buffer

    E-Print Network [OSTI]

    diodes have been fabricated utilizing simple top and bottom contacts. The highest LED power of 0.18µW perYellow-green emission for ETS-LEDs and lasers based on a strained­InGaP quantum well with a reduced power of 0.08µW per facet at 20mA. For a quantum well composition of In0.37Ga0.63P and an overall

  2. Which LED Lighting Products Would You Consider Trying?

    Broader source: Energy.gov [DOE]

    Which LED lighting products would you consider trying? Or, if you're already using LEDs, what do you think of them?

  3. (Expired) Nationwide Limited Public Interest Waiver for LED Lighting...

    Energy Savers [EERE]

    (Expired) Nationwide Limited Public Interest Waiver for LED Lighting and HVAC Units: February 11, 2010 (Expired) Nationwide Limited Public Interest Waiver for LED Lighting and HVAC...

  4. Demonstration of LED Street Lighting in Kansas City, MO Kinzey...

    Office of Scientific and Technical Information (OSTI)

    Street Lighting in Kansas City, MO Kinzey, Bruce R.; Royer, Michael P.; Hadjian, M.; Kauffman, Rick LED streetlighting; field illuminance measurement LED streetlighting; field...

  5. Technical Feasibility Assessment of LED Roadway Lighting on the...

    Office of Scientific and Technical Information (OSTI)

    Technical Feasibility Assessment of LED Roadway Lighting on the Golden Gate Bridge Tuenge, Jason R. LED; induction; ceramic metal halide; plasma; roadway lighting; Golden Gate...

  6. Titanium-dioxide nanotube p-n homojunction diode

    SciTech Connect (OSTI)

    Alivov, Yahya E-mail: pnagpal@colorado.edu; Ding, Yuchen; Singh, Vivek; Nagpal, Prashant E-mail: pnagpal@colorado.edu

    2014-12-29

    Application of semiconductors in functional optoelectronic devices requires precise control over their doping and formation of junction between p- and n-doped semiconductors. While doped thin films have led to several semiconductor devices, need for high-surface area nanostructured devices for photovoltaic, photoelectrochemical, and photocatalytic applications has been hindered by lack of desired doping in nanostructures. Here, we show titanium-dioxide (TiO{sub 2}) nanotubes doped with nitrogen (N) and niobium (Nb) as acceptors and donors, respectively, and formation of TiO{sub 2} nanotubes p-n homojunction. This TiO{sub 2}:N/TiO{sub 2}:Nb homojunction showed distinct diode-like behaviour with rectification ratio of 1115 at ±5?V and exhibited good photoresponse for ultraviolet light (??=?365?nm) with sensitivity of 0.19?A/W at reverse bias of ?5?V. These results can have important implications for development of nanostructured metal-oxide solar-cells, photodiodes, LED's, photocatalysts, and photoelectrochemical devices.

  7. Abbreviated epitaxial growth mode (AGM) method for reducing cost and improving quality of LEDs and lasers

    DOE Patents [OSTI]

    Tansu, Nelson; Chan, Helen M; Vinci, Richard P; Ee, Yik-Khoon; Biser, Jeffrey

    2013-09-24

    The use of an abbreviated GaN growth mode on nano-patterned AGOG sapphire substrates, which utilizes a process of using 15 nm low temperature GaN buffer and bypassing etch-back and recovery processes during epitaxy, enables the growth of high-quality GaN template on nano-patterned AGOG sapphire. The GaN template grown on nano-patterned AGOG sapphire by employing abbreviated growth mode has two orders of magnitude lower threading dislocation density than that of conventional GaN template grown on planar sapphire. The use of abbreviated growth mode also leads to significant reduction in cost of the epitaxy. The growths and characteristics of InGaN quantum wells (QWs) light emitting diodes (LEDs) on both templates were compared. The InGaN QWs LEDs grown on the nano-patterned AGOG sapphire demonstrated at least a 24% enhancement of output power enhancement over that of LEDs grown on conventional GaN templates.

  8. High-Efficiency Non-Polar GaN-Based LEDs

    SciTech Connect (OSTI)

    Paul Fini

    2010-11-30

    Inlustra Technologies with subcontractor U.C. Santa Barbara conducted a project with the principle goal of demonstrating high internal quantum efficiency blue (430 nm) and green (540nm) light emitting diodes (LEDs) on low-defect density non-polar GaN wafers. Inlustra pursued the fabrication of smooth thick a-plane and m-plane GaN films, as well as defect reduction techniques such as lateral epitaxial overgrowth (LEO) to uniformly lower dislocation density in these films. Limited free-standing wafers were produced as well. By the end of the reporting period, Inlustra had met its milestone of dislocation reduction to < 5 x 10{sup 6} cm{sup -2}. Stacking faults were still present in appreciable density ({approx} 1 x 10{sup 5} cm{sup -1}), but were not the primary focus of defect reduction since there have been no published studies establishing their detrimental effects on LED performance. Inlustra's LEO progress built a solid foundation upon which further commercial development of GaN substrates will occur. UCSB encountered multiple delays in its LED growth and fabrication efforts due to unavoidable facilities outages imposed by ongoing construction in an area adjacent to the metalorganic chemical vapor deposition (MOCVD) laboratory. This, combined with the large amount of ab initio optimization required for the MOCVD system used during the project, resulted in unsatisfactory LED progress. Although numerous blue-green photoluminescence results were obtained, only a few LED structures exhibited electroluminescence at appreciable levels. UCSB also conducting extensive modeling (led by Prof. Van de Walle) on the problem of non-radiative Auger recombination in GaN-based LED structures, which has been posited to contribute to LED efficiency 'droop' at elevated current density. Unlike previous modeling efforts, UCSB's approach was truly a first-principles ab initio methodology. Building on solid numerical foundations, the Auger recombination rates of In{sub x}Ga{sub 1-x}N alloys were calculated from first-principles density-functional and many-body-perturbation theory. The differing mechanisms of inter- and intra-band recombination were found to affect different parts of the emission spectrum. In the blue to green spectral region and at room temperature the Auger coefficient was calculated to be as large as 2 x 10{sup -30} cm{sup 6} s{sup -1}; in the infrared it is even larger. These results indicated that Auger recombination may be responsible for the loss of quantum efficiency that affects InGaN-based light emitters, whether on non-polar or polar crystal planes.

  9. Fidelity Decay for Phase Space Displacements

    E-Print Network [OSTI]

    Diego V. Bevilaqua; Eric J. Heller

    2004-09-03

    In this letter we analyse the behavior of fidelity decay under a very specific kind of perturbation: phase space displacements. Under these perturbations, systems will decay following the Lyapunov regime only. Others universal regimes discussed in the literature are not presented in this case; instead, for small values of the perturbation we observe quantum freeze of the fidelity. We also show that it is possible to connect this result with the incoherent neutron scattering problem

  10. EC-LEDS Transport | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTIONRobertsdale, Alabama (UtilityInstrumentsAreafor GeothermalNorthWorldwideMitigation | OpenEC-LEDS

  11. Category:LEDS Toolkit | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar Energy LLCLtd Jump to: navigation, searchsource History ViewEnFederalLEDS

  12. LED Green Power Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EAInvervar HydroElectric Cooperative(Redirected fromUni Land JV JumpLED

  13. SemiLEDs | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EIS Report UrlNM-bRenewableSMUDSectional Modelof the| OpenSemiLEDs Jump

  14. LedEngin Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource History ViewInformationWinds Jump to:Laredo RidgeLaymanJersey:LedEngin Inc

  15. 2 Gb/s ?LED-APD Based Visible Light Communications Using Feed-forward Pre-equalization and PAM-4 Modulation

    E-Print Network [OSTI]

    Li, X.; Bamiedakis, N.; Guo, X.; McKendry, J. J. D.; Xie, E.; Ferreira, R.; Gu, E.; Dawson, M. D.; Penty, R. V.; White, I. H.

    2015-10-01

    ) , E. Gu (2) , M. D. Dawson (2) , R. V. Penty (2) , I. H. White (2) ((1) Electrical Engineering Division, Engineering Department, University of Cambridge, Cambridge CB3 0FA, UK; Email address: xl336@cam.ac.uk (2) Institute of Photonics, SUPA... as light-emitting diodes (LEDs) can provide high-speed data transmission as well as illumination. Such LED- based optical wireless systems are a potential solution to the spectrum crunch in radio frequency systems as they can make use of hundreds...

  16. LED Surgical Task Lighting Scoping Study: A Hospital Energy Alliance Project

    SciTech Connect (OSTI)

    Tuenge, Jason R.

    2011-01-17

    Tungsten-halogen (halogen) lamps have traditionally been used to light surgical tasks in hospitals, even though they are in many respects ill-suited to the application due to the large percentage of radiant energy outside the visible spectrum and issues with color rendering/quality. Light-emitting diode (LED) technology offers potential for adjustable color and improved color rendition/quality, while simultaneously reducing side-effects from non-visible radiant energy. It also has the potential for significant energy savings, although this is a fairly narrow application in the larger commercial building energy use sector. Based on analysis of available products and Hospital Energy Alliance member interest, it is recommended that a product specification and field measurement procedure be developed for implementation in demonstration projects.

  17. Electrical spin injection using GaCrN in a GaN based spin light emitting diode

    SciTech Connect (OSTI)

    Banerjee, D.; Ganguly, S.; Saha, D.; Adari, R.; Sankaranarayan, S.; Kumar, A.; Aldhaheri, R. W.; Hussain, M. A.; Balamesh, A. S.

    2013-12-09

    We have demonstrated electrical spin-injection from GaCrN dilute magnetic semiconductor (DMS) in a GaN-based spin light emitting diode (spin-LED). The remanent in-plane magnetization of the thin-film semiconducting ferromagnet has been used for introducing the spin polarized electrons into the non-magnetic InGaN quantum well. The output circular polarization obtained from the spin-LED closely follows the normalized in-plane magnetization curve of the DMS. A saturation circular polarization of ?2.5% is obtained at 200?K.

  18. New and Underutilized Technology: High Bay LED Lighting

    Broader source: Energy.gov [DOE]

    The following information outlines key deployment considerations for high bay LED lighting within the Federal sector.

  19. Text-Alternative Version: LED Essentials- Technology, Applications, Advantages, Disadvantages

    Office of Energy Efficiency and Renewable Energy (EERE)

    Below is the text-alternative version of the LED Essentials - Technology, Applications, Advantages, Disadvantages webcast.

  20. GaN-Ready Aluminum Nitride Substrates for Cost-Effective, Very Low Dislocation Density III-Nitride LED's

    SciTech Connect (OSTI)

    Sandra Schujman; Leo Schowalter

    2010-10-15

    The objective of this project was to develop and then demonstrate the efficacy of a costeffective approach for a low defect density substrate on which AlInGaN LEDs can be fabricated. The efficacy of this “GaN-ready” substrate would then be tested by growing high efficiency, long lifetime InxGa1-xN blue LEDs. The approach used to meet the project objectives was to start with low dislocation density AlN single-crystal substrates and grow graded AlxGa1-xN layers on top. Pseudomorphic AlxGa1-xN epitaxial layers grown on bulk AlN substrates were used to fabricate light emitting diodes and demonstrate better device performance as a result of the low defect density in these layers when benched marked against state-of-the-art LEDs fabricated on sapphire substrates. The pseudomorphic LEDs showed excellent output powers compared to similar wavelength devices grown on sapphire substrates, with lifetimes exceeding 10,000 hours (which was the longest time that could reliably be estimated). In addition, high internal quantum efficiencies were demonstrated at high driving current densities even though the external quantum efficiencies were low due to poor photon extraction. Unfortunately, these pseudomorphic LEDs require high Al content so they emit in the ultraviolet. Sapphire based LEDs typically have threading dislocation densities (TDD) > 108 cm-2 while the pseudomorphic LEDs have TDD ? 105 cm-2. The resulting TDD, when grading the AlxGa1-xN layer all the way to pure GaN to produce a “GaN-ready” substrate, has varied between the mid 108 down to the 106 cm-2. These inconsistencies are not well understood. Finally, an approach to improve the LED structures on AlN substrates for light extraction efficiency was developed by thinning and roughening the substrate.

  1. Ultraviolet emission from a multi-layer graphene/MgZnO/ZnO light-emitting diode

    SciTech Connect (OSTI)

    Kang, Jang-Won; Choi, Yong-Seok; Goo Kang, Chang; Hun Lee, Byoung [School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Kim, Byeong-Hyeok [Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Tu, C. W. [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093-0407 (United States); Park, Seong-Ju, E-mail: sjpark@gist.ac.kr [School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

    2014-02-03

    We report on ultraviolet emission from a multi-layer graphene (MLG)/MgZnO/ZnO light-emitting diodes (LED). The p-type MLG and MgZnO in the MLG/MgZnO/ZnO LED are used as transparent hole injection and electron blocking layers, respectively. The current-voltage characteristics of the MLG/MgZnO/ZnO LED show that current transport is dominated by tunneling processes in the MgZnO barrier layer under forward bias conditions. The holes injected from p-type MLG recombine efficiently with the electrons accumulated in ZnO, and the MLG/MgZnO/ZnO LED shows strong ultraviolet emission from the band edge of ZnO and weak red-orange emission from the deep levels of ZnO.

  2. Enhancement in light emission and electrical efficiencies of a silicon nanocrystal light-emitting diode by indium tin oxide nanowires

    SciTech Connect (OSTI)

    Huh, Chul, E-mail: chuh@etri.re.kr; Kim, Bong Kyu; Ahn, Chang-Geun; Kim, Sang-Hyeob [IT Convergence Technology Research Laboratory, Electronics and Telecommunications Research Institute, Daejeon 305-350 (Korea, Republic of); Choi, Chel-Jong [Department of BIN Fusion Technology, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2014-07-21

    We report an enhancement in light emission and electrical efficiencies of a Si nanocrystal (NC) light-emitting diode (LED) by employing indium tin oxide (ITO) nanowires (NWs). The formed ITO NWs (diameter?LED were significantly improved, which was attributed to an enhancement in the current spreading property due to densely interconnecting ITO NWs. In addition, light output power and wall-plug efficiency from the Si NC LED were enhanced by 45% and 38%, respectively. This was originated from an enhancement in the escape probability of the photons generated in the Si NCs due to multiple scatterings at the surface of ITO NWs acting as a light waveguide. We show here that the use of the ITO NWs can be very useful for realizing a highly efficient Si NC LED.

  3. Tailoring of polarization in electron blocking layer for electron confinement and hole injection in ultraviolet light-emitting diodes

    SciTech Connect (OSTI)

    Lu, Yu-Hsuan; Pilkuhn, Manfred H. [Department of Electrical Engineering, Institute of Microelectronics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China); Fu, Yi-Keng; Chu, Mu-Tao [Electronics and Optoelectronics Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan (China); Huang, Shyh-Jer, E-mail: yksu@mail.ncku.edu.tw, E-mail: totaljer48@gmail.com [Department of Electrical Engineering, Institute of Microelectronics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China); Department of Electrical Engineering, University of California at Los Angeles, Los Angeles, California 90095 (United States); Su, Yan-Kuin, E-mail: yksu@mail.ncku.edu.tw, E-mail: totaljer48@gmail.com [Department of Electrical Engineering, Institute of Microelectronics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China); Department of Electronic Engineering, Kun-Shan University, Tainan 71003, Taiwan (China); Wang, Kang L. [Department of Electrical Engineering, University of California at Los Angeles, Los Angeles, California 90095 (United States)

    2014-03-21

    The influence of the AlGaN electron blocking layer (EBL) with graded aluminum composition on electron confinement and hole injection in AlGaN-based ultraviolet light-emitting diodes (LEDs) are investigated. The light output power of LED with graded AlGaN EBL was markedly improved, comparing to LED with conventional EBL. In experimental results, a high increment of 86.7% can be obtained in light output power. Simulation analysis shows that via proper modification of the barrier profile from the last barrier of the active region to EBL, not only the elimination of electron overflow to p-type layer can be achieved but also the hole injection into the active region can be enhanced, compared to a conventional LED structure. The dominant factor to the performance improvement is shown to be the modulation of polarization field by the graded Al composition in EBL.

  4. High-Performance Organic Light-Emitting Diodes Using ITO

    E-Print Network [OSTI]

    Ho, Seng-Tiong

    High-Performance Organic Light-Emitting Diodes Using ITO Anodes Grown on Plastic by Room,* Mark E. Madsen, Antonio DiVenere, and Seng-Tiong Ho Organic light-emitting diodes (OLEDs) fabricated

  5. Electroluminescence from Organometallic Lead Halide Perovskite - Conjugated Polymer Diodes

    E-Print Network [OSTI]

    Sadhanala, Aditya; Kumar, Abhishek; Pathak, Sandeep; Rao, Akshay; Steiner, Ullrich; Greenham, Neil C.; Snaith, Henry J.; Friend, Richard H.

    2015-02-19

    Organometallic lead perovskite-based solar cells can be converted to light-emitting diodes by engineering the current density. Diodes are fabricated with adjacent perovskite and conjugated polymer layers using orthogonal solvents. Under forward bias...

  6. Evaluation of Metal Halide, Plasma, and LED Lighting Technologies for a Hydrogen Fuel Cell Mobile Light (H 2 LT)

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

    Miller, L. B.; Donohoe, S. P.; Jones, M. H.; White, W. A.; Klebanoff, L. E.; Velinsky, S. A.

    2015-04-22

    This article reports on the testing and comparison of a prototype hydrogen fuel cell light tower (H2LT) and a conventional diesel-powered metal halide light trailer for use in road maintenance and construction activities. The prototype was originally outfitted with plasma lights and then with light-emitting diode (LED) luminaires. Light output and distribution, lighting energy efficiency (i.e., efficacy), power source thermal efficiency, and fuel costs are compared. The metal halide luminaires have 2.2 and 3.1 times more light output than the plasma and LED luminaires, respectively, but they require more power/lumen to provide that output. The LED luminaires have 1.6 timesmore »better light efficacy than either the metal halide or plasma luminaires. The light uniformity ratios produced by the plasma and LED towers are acceptable. The fuel cell thermal efficiency at the power required to operate the plasma lights is 48%, significantly higher than the diesel generator efficiency of 23% when operating the metal halide lights. Due to the increased efficiency of the fuel cell and the LED lighting, the fuel cost per lumen-hour of the H2LT is 62% of the metal halide diesel light tower assuming a kilogram of hydrogen is twice the cost of a gallon of diesel fuel.« less

  7. PN JUNCTIONS; DIODES Lecture 10-V

    E-Print Network [OSTI]

    Smith, Nathanael J.

    ://www.instructables.com/id/LED-Throwies/ http://ftechblog.com/comparison-between-lcd-and-led-tv/ #12;Applications II ­ Photovoltaics 15 http://en.wikipedia.org/wiki/Solar_panel

  8. Demonstration Assessment of Light-Emitting Diode (LED) Retrofit Lamps at Intercontinental Hotel in San Francisco, CA

    SciTech Connect (OSTI)

    Miller, Naomi J.; Curry, Ku'Uipo J.

    2010-11-01

    This document is a report of observations and results obtained from a lighting demonstration project conducted under the U.S. Department of Energy (DOE) GATEWAY Demonstration Program. The program supports demonstrations of high-performance solid-state lighting (SSL) products in order to develop empirical data and experience with in-the-field applications of this advanced lighting technology. The DOE GATEWAY Demonstration Program focuses on providing a source of independent, third-party data for use in decision-making by lighting users and professionals; this data should be considered in combination with other information relevant to the particular site and application under examination. Each GATEWAY Demonstration compares SSL products against the incumbent technologies used in that location. Depending on available information and circumstances, the SSL product may also be compared to alternate lighting technologies. Though products demonstrated in the GATEWAY program have been prescreened and tested to verify their actual performance, DOE does not endorse any commercial product or in any way guarantee that users will achieve the same results through use of these products.

  9. Aalborg Universitet Water cooling of high power light emitting diode

    E-Print Network [OSTI]

    Berning, Torsten

    Aalborg Universitet Water cooling of high power light emitting diode Sørensen, Henrik Published in Citation for published version (APA): Sørensen, H. (2012). Water cooling of high power light emitting diode from vbn.aau.dk on: juli 07, 2015 #12;Water Cooling of High Power Light Emitting Diode Henrik Sørensen

  10. Organic Light-Emitting Diodes Having Carbon Nanotube Anodes

    E-Print Network [OSTI]

    Gruner, George

    , flexible anodes for organic light-emitting diodes (OLEDs). For polymer-based OLEDs having the structure applications. Polymer and small molecule-based organic light-emitting diodes (OLEDs) are rapidly approachingOrganic Light-Emitting Diodes Having Carbon Nanotube Anodes Jianfeng Li, Liangbing Hu, Lian Wang

  11. Correlation of Beam Electron and LED Signal Losses under Irradiation and Long-term Recovery of Lead Tungstate Crystals

    E-Print Network [OSTI]

    V. A. Batarin; J. Butler; A. M. Davidenko; A. A. Derevschikov; Y. M. Goncharenko; V. N. Grishin; V. A. Kachanov; A. S. Konstantinov; V. I. Kravtsov; Y. Kubota; V. S. Lukanin; Y. A. Matulenko; Y. M. Melnick; A. P. Meschanin; N. E. Mikhalin; N. G. Minaev; V. V. Mochalov; D. A. Morozov; L. V. Nogach; A. V. Ryazantsev; P. A. Semenov; V. K. Semenov; K. E. Shestermanov; L. F. Soloviev; S. Stone; A. V. Uzunian; A. N. Vasiliev; A. E. Yakutin; J. Yarba

    2005-04-13

    Radiation damage in lead tungstate crystals reduces their transparency. The calibration that relates the amount of light detected in such crystals to incident energy of photons or electrons is of paramount importance to maintaining the energy resolution the detection system. We report on tests of lead tungstate crystals, read out by photomultiplier tubes, exposed to irradiation by monoenergetic electron or pion beams. The beam electrons themselves were used to measure the scintillation light output, and a blue light emitting diode (LED) was used to track variations of crystals transparency. We report on the correlation of the LED measurement with radiation damage by the beams and also show that it can accurately monitor the crystals recovery from such damage.

  12. Integrated injection-locked semiconductor diode laser

    DOE Patents [OSTI]

    Hadley, G. Ronald (Albuquerque, NM); Hohimer, John P. (Albuquerque, NM); Owyoung, Adelbert (Albuquerque, NM)

    1991-01-01

    A continuous wave integrated injection-locked high-power diode laser array is provided with an on-chip independently-controlled master laser. The integrated injection locked high-power diode laser array is capable of continuous wave lasing in a single near-diffraction limited output beam at single-facet power levels up to 125 mW (250 mW total). Electronic steering of the array emission over an angle of 0.5 degrees is obtained by varying current to the master laser. The master laser injects a laser beam into the slave array by reflection of a rear facet.

  13. Integrated injection-locked semiconductor diode laser

    DOE Patents [OSTI]

    Hadley, G.R.; Hohimer, J.P.; Owyoung, A.

    1991-02-19

    A continuous wave integrated injection-locked high-power diode laser array is provided with an on-chip independently-controlled master laser. The integrated injection locked high-power diode laser array is capable of continuous wave lasing in a single near-diffraction limited output beam at single-facet power levels up to 125 mW (250 mW total). Electronic steering of the array emission over an angle of 0.5 degrees is obtained by varying current to the master laser. The master laser injects a laser beam into the slave array by reflection of a rear facet. 18 figures.

  14. Diode amplifier of modulated optical beam power

    SciTech Connect (OSTI)

    D'yachkov, N V; Bogatov, A P; Gushchik, T I; Drakin, A E [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2014-11-30

    Analytical relations are obtained between characteristics of modulated light at the output and input of an optical diode power amplifier operating in the highly saturated gain regime. It is shown that a diode amplifier may act as an amplitude-to-phase modulation converter with a rather large bandwidth (?10 GHz). The low sensitivity of the output power of the amplifier to the input beam power and its high energy efficiency allow it to be used as a building block of a high-power multielement laser system with coherent summation of a large number of optical beams. (lasers)

  15. Superconducting inductive displacement detection of a microcantilever

    SciTech Connect (OSTI)

    Vinante, A., E-mail: anvinante@fbk.eu [Istituto di Fotonica e Nanotecnologie, CNR - Fondazione Bruno Kessler, I-38123 Povo, Trento (Italy)

    2014-07-21

    We demonstrate a superconducting inductive technique to measure the displacement of a micromechanical resonator. In our scheme, a type I superconducting microsphere is attached to the free end of a microcantilever and approached to the loop of a dc Superconducting Quantum Interference Device (SQUID) microsusceptometer. A local magnetic field as low as 100??T, generated by a field coil concentric to the SQUID, enables detection of the cantilever thermomechanical noise at 4.2?K. The magnetomechanical coupling and the magnetic spring are in good agreement with image method calculations assuming pure Meissner effect. These measurements are relevant to recent proposals of quantum magnetomechanics experiments based on levitating superconducting microparticles.

  16. Displacement Transfer Zone | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTIONRobertsdale, Alabama (UtilityInstrumentsArea (DOE GTP)Displacement Transfer Zone Jump to:

  17. Spin-current diode with a ferromagnetic semiconductor

    SciTech Connect (OSTI)

    Sun, Qing-Feng Xie, X. C.

    2015-05-04

    Diode is a key device in electronics: the charge current can flow through the device under a forward bias, while almost no current flows under a reverse bias. Here, we propose a corresponding device in spintronics: the spin-current diode, in which the forward spin current is large but the reversed one is negligible. We show that the lead/ferromagnetic quantum dot/lead system and the lead/ferromagnetic semiconductor/lead junction can work as spin-current diodes. The spin-current diode, a low dissipation device, may have important applications in spintronics, as the conventional charge-current diode does in electronics.

  18. Synthesis and optical properties of cadmium selenide quantum dots for white light-emitting diode application

    SciTech Connect (OSTI)

    Xu, Xianmei; Wang, Yilin; Gule, Teri; Luo, Qiang [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 53000 (China); Zhou, Liya, E-mail: zhouliyatf@163.com [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 53000 (China); Gong, Fuzhong [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 53000 (China)

    2013-03-15

    Highlights: ? Stable CdSe QDs were synthesized by the one-step and two-level process respectively. ? The fabricated white LEDs show good white balance. ? CdSe QDs present well green to yellow band luminescence. ? CdSe QDs displayed a broad excitation band. - Abstract: Yellow light-emitting cadmium selenide quantum dots were synthesized using one-step and two-step methods in an aqueous medium. The structural luminescent properties of these quantum dots were investigated. The obtained cadmium selenide quantum dots displayed a broad excitation band suitable for blue or near-ultraviolet light-emitting diode applications. White light-emitting diodes were fabricated by coating the cadmium selenide samples onto a 460 nm-emitting indium gallium nitrite chip. Both samples exhibited good white balance. Under a 20 mA working current, the white light-emitting diode fabricated via the one-step and two-step methods showed Commission Internationale de l’Éclairage coordinates at (0.27, 0.23) and (0.27, 0.33), respectively, and a color rendering index equal to 41 and 37, respectively. The one-step approach was simpler, greener, and more effective than the two-step approach. The one-step approach can be enhanced by combining cadmium selenide quantum dots with proper phosphors.

  19. Entangled Light Emission From a Diode

    SciTech Connect (OSTI)

    Stevenson, R. M.; Shields, A. J. [Toshiba Research Europe Limited, 208 Cambridge Science Park, Cambridge CB4 0GZ (United Kingdom); Salter, C. L. [Toshiba Research Europe Limited, 208 Cambridge Science Park, Cambridge CB4 0GZ (United Kingdom); Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Farrer, I.; Nicoll, C. A.; Ritchie, D. A. [Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom)

    2011-12-23

    Electrically-driven entangled photon generation is demonstrated for the first time using a single semiconductor quantum dot embedded in a light emitting diode structure. The entanglement fidelity is shown to be of sufficient quality for applications such as quantum key distribution.

  20. The role of triplet states in the emission mechanism of polymer light-emitting diodes

    E-Print Network [OSTI]

    M. Arif; S. Mukhopadhyay; S. Ramasesha; S. Guha

    2009-03-01

    The blue emission of polyfluorene (PF) based light-emitting diodes (LEDs) is known to degrade due to a low energy green emission, which hitherto has been attributed to oxidative defects. By studying the electroluminescence from ethyl-hexyl substituted PF LEDs in the presence of oxygen and in an inert atmosphere, and by using trace quantities of paramagnetic impurities (PM) in the polymer, we show that the triplet states play a major role in the low energy emission mechanism. Our time-dependent many-body studies show that there is a large cross-section for the triplet formation in the electron-hole recombination process in presence of PM, and intersystem crossing from excited singlet to triplet states.

  1. A hole accelerator for InGaN/GaN light-emitting diodes

    SciTech Connect (OSTI)

    Zhang, Zi-Hui; Liu, Wei; Tan, Swee Tiam; Ji, Yun; Wang, Liancheng; Zhu, Binbin; Zhang, Yiping; Lu, Shunpeng; Zhang, Xueliang; Hasanov, Namig; Sun, Xiao Wei, E-mail: EXWSUN@ntu.edu.sg, E-mail: VOLKAN@stanfordalumni.org [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Demir, Hilmi Volkan, E-mail: EXWSUN@ntu.edu.sg, E-mail: VOLKAN@stanfordalumni.org [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Department of Electrical and Electronics, Department of Physics, and UNAM-Institute of Material Science and Nanotechnology, Bilkent University, TR-06800 Ankara (Turkey)

    2014-10-13

    The quantum efficiency of InGaN/GaN light-emitting diodes (LEDs) has been significantly limited by the insufficient hole injection, and this is caused by the inefficient p-type doping and the low hole mobility. The low hole mobility makes the holes less energetic, which hinders the hole injection into the multiple quantum wells (MQWs) especially when a p-type AlGaN electron blocking layer (EBL) is adopted. In this work, we report a hole accelerator to accelerate the holes so that the holes can obtain adequate kinetic energy, travel across the p-type EBL, and then enter the MQWs more efficiently and smoothly. In addition to the numerical study, the effectiveness of the hole accelerator is experimentally shown through achieving improved optical output power and reduced efficiency droop for the proposed InGaN/GaN LED.

  2. Revolutionary Method for Increasing the Efficiency of White Light Quantum Dot LEDs

    SciTech Connect (OSTI)

    Duty, Chad E [ORNL; Bennett, Charlee J C [ORNL; Sabau, Adrian S [ORNL; Jellison Jr, Gerald Earle [ORNL; Boudreaux, Philip R [ORNL; Walker, Steven C [ORNL; Ott, Ronald D [ORNL

    2011-01-01

    Covering a light-emitting diode (LED) with quantum dots (QDs) can produce a broad spectrum of white light. However, current techniques for applying QDs to LEDs suffer from a high density of defects and a non-uniform distribution of QDs, which respec-tively diminish the efficiency and quality of emitted light. Oak Ridge National Laboratory (ORNL) has the unique capability to thermally anneal QD structures at extremely high power densities for very short durations. This process, called pulse thermal proc-essing (PTP), reduces the number of point defects while main-taining the size and shape of the original QD nanostructure. Therefore, the efficiency of the QD wavelength conversion layer is improved without altering the emission spectrum defined by the size distribution of the quantum dot nanoparticles. The cur-rent research uses a thermal model to predict annealing tempera-tures during PTP and demonstrates up to a 300% increase in pho-toluminescence for QDs on passive substrates

  3. Demonstration of LED Retrofit Lamps at the Jordan Schnitzer Museum of Art

    SciTech Connect (OSTI)

    Miller, Naomi J.

    2011-09-01

    The Jordan Schnitzer Museum of Art in Eugene, Oregon, houses a remarkable permanent collection of Asian art and antiquities, modern art, and sculpture, and also hosts traveling exhibitions. In the winter and spring of 2011, a series of digital photographs by artist Chris Jordan, titled "Running the Numbers," was exhibited in the Coeta and Donald Barker Special Exhibitions Gallery. These works graphically illustrate waste (energy, money, health, consumer objects, etc.) in contemporary culture. The Bonneville Power Administration and the Eugene Water and Electricity Board provided a set of Cree 12W light-emitting diode (LED) PAR38 replacement lamps (Cree LRP38) for the museum to test for accent lighting in lieu of their standard Sylvania 90W PAR38 130V Narrow Flood lamps (which draw 78.9W at 120V). At the same time, the museum tested LED replacement lamps from three other manufacturers, and chose the Cree lamp as the most versatile and most appropriate color product for this exhibit. The lamps were installed for the opening of the show in January 2011. This report describes the process for the demonstration, the energy and economic results, and results of a survey of the museum staff and gallery visitors on four similar clusters of art lighted separately by four PAR38 lamps.

  4. Regenerative braking on bicycles to power LED safety flashers

    E-Print Network [OSTI]

    Collier, Ian M

    2005-01-01

    This work develops a method for capturing some of the kinetic energy ordinarily lost during braking on bicycles to power LED safety flashers. The system is designed to eliminate: (a) battery changing in popular LED flashers, ...

  5. Model Specification for LED Roadway Luminaires, V2.0

    Office of Energy Efficiency and Renewable Energy (EERE)

    Version 2.0 of the Model Specification for LED Roadway Luminaires is now available. Changes are substantial and include streamlined structure and formatting, new diagrams, updated references, and leveraging of LED Lighting Facts® program guidance.

  6. DOE Publishes GATEWAY Report on LED Lighting in a Performing...

    Energy Savers [EERE]

    LED Lighting in a Performing Arts Setting DOE Publishes GATEWAY Report on LED Lighting in a Performing Arts Setting August 6, 2014 - 2:46pm Addthis The U.S. Department of Energy...

  7. New DOE Report Estimates LED Savings in Common Lighting Applications...

    Energy Savers [EERE]

    New DOE Report Estimates LED Savings in Common Lighting Applications New DOE Report Estimates LED Savings in Common Lighting Applications July 24, 2015 - 11:00am Addthis The U.S....

  8. EECBG Success Story: Solar LED Light Pilot Project Illuminates...

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

    LED Light Pilot Project Illuminates the Way in Alabama This is one of the 100 decorative solar-powered LED lights that replaced natural gas-powered streetlights in the city of...

  9. Text-Alternative Version: Challenges in LED Research and Development

    Broader source: Energy.gov [DOE]

    Narrator: LEDs have made remarkable progress in the past decade and gained a strong foothold in the US marketplace. In 2012, LED lighting saved an estimated 71 trillion BTUs, equivalent to annual...

  10. Reducing LED Costs Through Innovation | Department of Energy

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

    Reducing LED Costs Through Innovation Reducing LED Costs Through Innovation November 19, 2013 - 3:49pm Addthis A combination solid-state laser turret cutter and stamping machine...

  11. Design, construction and analysis of an LED strobe controller

    E-Print Network [OSTI]

    Villalva, Nicholas E

    2012-01-01

    In this thesis, I describe an LED strobe controller that I designed and built. With the advent of much brighter LEDs, it is possible to create stroboscopes with both high intensity output and high maximum flash rates. ...

  12. MOF Coating a Promising Path to White LEDs

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

    MOF Coating a Promising Path to White LEDs MOF Coating a Promising Path to White LEDs Print Friday, 27 February 2015 17:11 Hu et al. designed a new yellow phosphor with high...

  13. LEDs Go Ivy League: Princeton’s Dillon Gymnasium

    Broader source: Energy.gov [DOE]

    View the video about LED lighting in Dillon Gymnasium, a focal point of sports and recreation at Princeton since 1947. William Evans discusses measurable benefits of LED lighting in the gym and...

  14. LED Parking Lot Lighting Working Group Fact Sheet

    SciTech Connect (OSTI)

    2008-10-01

    This fact sheet describes the Retailer Energy Alliance LED Parking Lot Lighting Working Group and its Technology Procurement Project.

  15. Text-Alternative Version: LED Replacements for Linear Fluorescent Lamps

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "LED Replacements for Linear Fluorescent Lamps" webcast, held June 20, 2011.

  16. Text-Alternative Version: Evaluating LED Street Lighting Solutions

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the Evaluating LED Street Lighting Solutions webcast, held July 20, 2010.

  17. Text-Alternative Version: LEDs for Interior Office Applications

    Office of Energy Efficiency and Renewable Energy (EERE)

    Below is the text-alternative version of the LEDs for Interior Office Applications webcast, held March 18, 2010.

  18. The Elusive “Life” of LEDs: How TM-21 Contributes to the Solution

    SciTech Connect (OSTI)

    Richman, Eric E.

    2011-11-18

    This magazine article discusses the issue of LED 'lifetime' and explains where TM-21 plays as part of the solution to this issue. In August 2011, the Illuminating Engineering Society (IES) published the TM-21 document entitled 'Lumen degradation lifetime estimation method for LED light sources.' TM-21 is the IES-recommended method for projecting lumen degradation of an LED package, array or module based on data collected according to LM-80. The lighting community expects TM-21 to become the standard method for projecting useful LED lighting product life at realistic operating temperature. This article presents the development process behind TM-21, and clarifies how and when to apply the lifetime extrapolation method to arrive at reasonable and useful estimations. Why TM-21 and why now? We are all familiar with the very real but sometimes exaggerated long-life attributes of LED technology. Not the least of these is the potential for very long life that helps make it an attractive design choice. The trick has been and continues to be how to measure or estimate this longevity to provide assurance to users of this technology's reliability (life) compared to other options. We also understand that the overall reliability of a complete LED lighting fixture can be affected by the reliability of individual product components (driver, lens, etc.) and should be accounted for in lifetime estimations. The useful life of standard lighting technologies is defined as the time to filament or cathode failure. For most of these lamps, the time period prior to failure exhibits acceptable levels of light output, as shown with the solid lines in Fig. 1. This makes it easy to determine when to replace the lamp. However, LEDs do not have filament burn-out that conveniently announces the end of life (dashed line in Fig. 1). Further, the rapid development of the technology and the desire to bring products to market in a timely manner does not allow for actual testing verification of the long lives claimed (100,000 or even 35,000 hours). As a result, the industry has come to accept a definition of the end of the useful life of an LED as the point when it no longer provides a specified level of light output. And finally, the life and performance of LED lighting products depends greatly on excess heat retained at the diode. This is why LEDs require testing at multiple temperatures such that when a source is installed in a luminaire, its actual operating temperature can be measured and lumen depreciation of the product can be derived. Therefore, to serve the solid-state lighting industry, the Technical Procedures Committee (TPC) of the IES proceeded to develop appropriate tests for use in rating LED product longevity. The initial need was a measure of the basic lumen degradation of LED source components identified by a module, package, or array of diodes and this came in the form of LM-80. Importantly, LM-80 only specifies how to measure lumen depreciation to a minimum of 6000 hours (but recommends testing to 10,000 hours or longer). LM-80 stops short of using that data to estimate any depreciation after that, which is where TM-21 comes in. The TM-21 working group (WG) as part of the IES TPC was formed to develop the lumen depreciation projection method and spent over three years exploring many options. The WG evaluated various projection options starting with an analysis of various mathematical, engineering-based models to provide effective depreciation fit and a useful projection method. Next, the WG analyzed LED lumen maintenance behavior using over 40 sets of LM-80-08 test data (20 sets with 10,000 hours or more) collected from four major LED manufacturers. The working group also examined the accuracy of proposed projections using various proposed models and LM-80 data that extended up to 15,000 hours.

  19. Semiconductors 4-bit I2C LED dimmer

    E-Print Network [OSTI]

    Berns, Hans-Gerd

    LEDs to 25 mA · Edge rate control on outputs · No glitch on power-up · Supports hot insertion · LowPhilips Semiconductors PCA9533 4-bit I2C LED dimmer Product data sheet Supersedes data of 2003 Sep 19 2004 Oct 01 INTEGRATED CIRCUITS #12;Philips Semiconductors Product data sheet PCA95334-bit I2C LED

  20. Breakthrough Makes LED Lights More Versatile Author: Andrea Thompson

    E-Print Network [OSTI]

    Rogers, John A.

    Breakthrough Makes LED Lights More Versatile Author: Andrea Thompson Source: http these limitations by combining the best of two worlds of LEDs to make ultrathin, ultrasmall and flexible light-sized inorganic LEDs after a request from Ford Motor Co. to create a third brake light for cars that would

  1. Aalborg Universitet Current-voltage model of LED light sources

    E-Print Network [OSTI]

    Munk-Nielsen, Stig

    Aalborg Universitet Current-voltage model of LED light sources Beczkowski, Szymon; Munk version (APA): Beczkowski, S., & Munk-Nielsen, S. (2012). Current-voltage model of LED light sources from vbn.aau.dk on: juli 06, 2015 #12;Current-voltage model of LED light sources Szymon Bczkowski, Stig

  2. CALiPER Snapshot Report: Indoor LED Luminaires

    SciTech Connect (OSTI)

    2014-04-01

    Snapshot reports use data from DOE's LED Lighting Facts product list to compare the LED performance to standard technologies, and are designed to help lighting retailers, distributors, designers, utilities, energy efficiency program sponsors, and other stakeholders understand the current state of the LED market and its trajectory.

  3. DOE Publishes Report on Color Stability of LED Lighting Products

    Broader source: Energy.gov [DOE]

    DOE has published a new GATEWAY report on color maintenance of LEDs in laboratory and field applications, summarizing color shift data of LED lamps used in real-world applications as well as LED products monitored by the CALiPER program in a lab

  4. Centrifugal deterministic lateral displacement separation system

    E-Print Network [OSTI]

    Mingliang Jiang; Aaron D. Mazzeo; German Drazer

    2015-07-22

    This work investigates the migration of spherical particles of different sizes in a centrifuge-driven deterministic lateral displacement (c-DLD) device. Specifically, we use a scaled-up model to study the motion of suspended particles through a square array of cylindrical posts under the action of centrifugation. Experiments show that separation of particles by size is possible depending on the orientation of the driving acceleration with respect to the array of posts (forcing angle). We focus on the fractionation of binary suspensions and measure the separation resolution at the outlet of the device for different forcing angles. We found excellent resolution at intermediate forcing angles, when large particles are locked to move at small migration angles but smaller particles follow the forcing angle more closely. Finally, we show that reducing the initial concentration (number) of particles, approaching the dilute limit of single particles, leads to increased resolution in the separation.

  5. Centrifugal deterministic lateral displacement separation system

    E-Print Network [OSTI]

    Jiang, Mingliang; Drazer, German

    2015-01-01

    This work investigates the migration of spherical particles of different sizes in a centrifuge-driven deterministic lateral displacement (c-DLD) device. Specifically, we use a scaled-up model to study the motion of suspended particles through a square array of cylindrical posts under the action of centrifugation. Experiments show that separation of particles by size is possible depending on the orientation of the driving acceleration with respect to the array of posts (forcing angle). We focus on the fractionation of binary suspensions and measure the separation resolution at the outlet of the device for different forcing angles. We found excellent resolution at intermediate forcing angles, when large particles are locked to move at small migration angles but smaller particles follow the forcing angle more closely. Finally, we show that reducing the initial concentration (number) of particles, approaching the dilute limit of single particles, leads to increased resolution in the separation.

  6. Optical inverse-square displacement sensor

    DOE Patents [OSTI]

    Howe, R.D.; Kychakoff, G.

    1989-09-12

    This invention comprises an optical displacement sensor that uses the inverse-square attenuation of light reflected from a diffused surface to calculate the distance from the sensor to the reflecting surface. Light emerging from an optical fiber or the like is directed onto the surface whose distance is to be measured. The intensity I of reflected light is angle dependent, but within a sufficiently small solid angle it falls off as the inverse square of the distance from the surface. At least a pair of optical detectors are mounted to detect the reflected light within the small solid angle, their ends being at different distances R and R + [Delta]R from the surface. The distance R can then be found in terms of the ratio of the intensity measurements and the separation length as given in an equation. 10 figs.

  7. Advantages of the Blue InGaN/GaN Light-Emitting Diodes with an AlGaN/GaN/AlGaN Quantum Well Structured Electron Blocking Layer

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    ABSTRACT: InGaN/GaN light-emitting diodes (LEDs) with p-(AlGaN/GaN/AlGaN) quantum well structured electron. The proposed QWEBL LED structure, in which a p-GaN QW layer is inserted in the p-AlGaN electron blocking layer the radiative recombination rates across the active region. Consequently, the light output power was enhanced

  8. Cree Sets New Benchmarks for LED Efficacy and Brightness

    Broader source: Energy.gov [DOE]

    Cree has successfully created a cool white LED prototype that delivers 107 lm/W at 350mA. This achievement builds on the Cree EZBright® LED chip platform, developed in part with prior funding support from DOE. Cree made the prototype LED under their DOE project focused on developing LED chips incorporating photonic crystal elements for improved light extraction and novel package technology for higher down-conversion efficiency compared to conventional LEDs. Based on a 1 millimeter-square chip, the new prototype LED produces white light with a CCT of 5500K and a CRI of 73. Integration of four of these prototype LEDs can produce luminous flux of more than 450 lumens.

  9. Low energy properties of the random displacement model

    E-Print Network [OSTI]

    Jeff Baker; Michael Loss; Günter Stolz

    2008-08-05

    We study low-energy properties of the random displacement model, a random Schr\\"odinger operator describing an electron in a randomly deformed lattice. All periodic displacement configurations which minimize the bottom of the spectrum are characterized. While this configuration is essentially unique for dimension greater than one, there are infinitely many different minimizing configurations in the one-dimensional case. The latter leads to unusual low energy asymptotics for the integrated density of states of the one-dimensional random displacement model. For symmetric Bernoulli-distributed displacements it has a $1/\\log^2$-singularity at the bottom of the spectrum. In particular, it is not H\\"older-continuous.

  10. Operator Splitting for Compressible Miscible Displacement in Porous Media

    E-Print Network [OSTI]

    Douglas Jr., Jim

    , relevant for tertiary recovery in petroleum reservoirs, have been related to incompressible ow problems. The numerical approximation of incom- pressible miscible displacement has been carefully investigated

  11. High efficiency InGaN/GaN light emitting diodes with asymmetric triangular multiple quantum wells

    SciTech Connect (OSTI)

    Chang, Chiao-Yun; Li, Hen; Lu, Tien-Chang, E-mail: timtclu@mail.nctu.edu.tw [Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan 300 (China)

    2014-03-03

    In this study, we demonstrated high efficiency InGaN/GaN light emitting diodes (LEDs) with asymmetric triangular multiple quantum wells (MQWs). Asymmetric triangular MQWs not only contribute to uniform carrier distribution in InGaN/GaN MQWs but also yield a low Auger recombination rate. In addition, asymmetric triangular MQWs with gallium face-oriented inclination band profiles can be immune from the polarization charge originating from typical c-plane InGaN/GaN quantum well structures. In the experiment, LEDs incorporated with asymmetric triangular MQWs with gallium face-oriented inclination band profiles exhibited a 60.0% external quantum efficiency at 20?mA and a 27.0% efficiency droop at 100?mA (corresponding to a current density of 69?A/cm{sup 2}), which accounted for an 11.7% efficiency improvement and a 31.1% droop reduction compared with symmetric square quantum well structure LEDs.

  12. Differential spectral responsivity measurement of photovoltaic detectors with a light-emitting-diode-based integrating sphere source

    SciTech Connect (OSTI)

    Zaid, Ghufron; Park, Seung-Nam; Park, Seongchong; Lee, Dong-Hoon

    2010-12-10

    We present an experimental realization of differential spectral responsivity measurement by using a light-emitting diode (LED)-based integrating sphere source. The spectral irradiance responsivity is measured by a Lambertian-like radiation field with a diameter of 40mm at the peak wavelengths of the 35 selectable LEDs covering a range from 280 to 1550nm. The systematic errors and uncertainties due to lock-in detection, spatial irradiance distribution, and reflection from the test detector are experimentally corrected or considered. In addition, we implemented a numerical procedure to correct the error due to the broad spectral bandwidth of the LEDs. The overall uncertainty of the DSR measurement is evaluated to be 2.2% (k=2) for Si detectors. To demonstrate its application, we present the measurement results of two Si photovoltaic detectors at different bias irradiance levels up to 120mW/cm{sup 2}.

  13. Direct periodic patterning of GaN-based light-emitting diodes by three-beam interference laser ablation

    SciTech Connect (OSTI)

    Kim, Jeomoh; Ji, Mi-Hee; Detchprohm, Theeradetch; Yuan, Dajun; Guo, Rui; Liu, Jianping; Asadirad, Mojtaba; Kwon, Min-Ki; Dupuis, Russell D.; Das, Suman; Ryou, Jae-Hyun

    2014-04-07

    We report on the direct patterning of two-dimensional periodic structures in GaN-based light-emitting diodes (LEDs) through laser interference ablation for the fast and reliable fabrication of periodic micro- and nano-structures aimed at enhancing light output. Holes arranged in a two-dimensional hexagonal lattice array having an opening size of 500?nm, depth of 50?nm, and a periodicity of 1??m were directly formed by three-beam laser interference without photolithography or electron-beam lithography processes. The laser-patterned LEDs exhibit an enhancement in light output power of 20% compared to conventional LEDs having a flat top surface without degradation of electrical and optical properties of the top p-GaN layer and the active region, respectively.

  14. High Efficiency LED Lamp for Solid-State Lighting

    SciTech Connect (OSTI)

    James Ibbetson

    2006-12-31

    This report contains a summary of technical achievements during a three-year project to demonstrate high efficiency, solid-state lamps based on gallium nitride/silicon carbide light-emitting diodes. Novel chip designs and fabrication processes are described for a new type of nitride light-emitting diode with the potential for very high efficiency. This work resulted in the demonstration of blue light-emitting diodes in the one watt class that achieved up to 495 mW of light output at 350 mA drive current, corresponding to quantum and wall plug efficiencies of 51% and 45%, respectively. When combined with a phosphor in Cree's 7090 XLamp package, these advanced blue-emitting devices resulted in white light-emitting diodes whose efficacy exceeded 85 lumens per watt. In addition, up to 1040 lumens at greater than 85 lumens per watt was achieved by combining multiple devices to make a compact white lamp module with high optical efficiency.

  15. Electrophoretic Deposition of Highly Efficient Phosphors for White Solid State Lighting using near UV-Emitting LEDs /

    E-Print Network [OSTI]

    Choi, Jae Ik

    2014-01-01

    application in white light emitting diode,” J. Mater. Res. ,S.Y. Choi. “White light-emitting diodes of GaN-based Sr 2phosphor for white light-emitting diodes prepared by sol–gel

  16. Advancements in ion diode and triode design

    SciTech Connect (OSTI)

    Cavenago, M., E-mail: cavenago@lnl.infn.it [INFN-LNL, viale dell'Universitá n.2, 35020 Legnaro (PD) (Italy)

    2014-02-15

    Selfconsistent laminar flow models, which enable to predict the optimal cathode and anode geometry in simple diodes, must be modified to account for the anode aperture and the effect of other electrodes. An equation for charge coupled to arbitrary laminar flows is here first presented and its numerical solutions are obtained with a new method, based on mesh transformations. It is found that a close match to theoretical flows requires an increase of the simple diode voltage v{sub 0} by an amount v{sub ?}, which, for a typical case designed for zero exit angle condition, are v{sub 0} = 0.7465 and v{sub ?} = 0.0294 in adimensional units. States “in” and “out” for the anode lens are also shown, where “out” is a new and nonlinear solution for the beam expansion in a drift tube.

  17. Infrared photoemitting diode having reduced work function

    DOE Patents [OSTI]

    Hirschfeld, T.B.

    1982-05-06

    In electro-optical detectors which include as elements a photoemitting photocathode and anode, a photoemitting diode is fabricated which lowers the diode's work function, thus reducing the cooling requirement typically needed for this type of device. The work function is reduced by sandwiching between the photocathode and anode a liquid meidum of the formula NR/sub 3/ and having an electron affinity for the electrons of the photocathode, which liquid medium permits free electrons leaving the photocathode to remain as stable solvated species in the liquid medium. Thus, highly light-absorbent, and therefore thin, metallic layers can be used for detection, thereby reducing dark current at a given temperature, with a consequent reduction in cooling requirements at constant detector performance.

  18. Numerical Modelling of Light Emission and Propagation in (Organic) LEDs with the Green's Tensor

    E-Print Network [OSTI]

    Floreano, Dario

    light emitting diodes, light emission, light extraction, dipole radiation, stratified media, layered surpasses incandescent sources by a factor of 2 and with further improvements light emitting diodes could on light extraction techniques from inorganic light emitting diodes we recommend chapter 5 in 1 . Organic

  19. INFLUENCE OF MASS ON DISPLACEMENT THRESHOLD

    SciTech Connect (OSTI)

    Setyawan, Wahyu; Selby, A.; Nandipati, Giridhar; Roche, Kenneth J.; Kurtz, Richard J.; Wirth, Brian D.

    2014-12-30

    Molecular dynamics simulations are performed to investigate the effect of mass on displacement threshold energy in Cr, Mo, Fe and W. For each interatomic potential, the mass of the atoms is varied among those metals for a total of 16 combinations. The average threshold energy over all crystal directions is calculated within the irreducible crystal directions using appropriate weighting factors. The weighting factors account for the different number of equivalent directions among the grid points and the different solid angle coverage of each grid point. The grid points are constructed with a Miller index increment of 1/24 for a total of 325 points. For each direction, 10 simulations each with a different primary-knock-on atom are performed. The results show that for each interatomic potential, the average threshold energy is insensitive to the mass; i.e., the values are the same within the standard error. In the future, the effect of mass on high-energy cascades for a given interatomic potential will be investigated.

  20. Gage for measuring displacements in rock samples

    DOE Patents [OSTI]

    Holcomb, David J. (Albuquerque, NM); McNamee, Michael J. (Albuquerque, NM)

    1986-01-01

    A gage for measuring diametral displacement within a rock sample for use in a rock mechanics laboratory and in the field, comprises a support ring housing a linear variable differential transformer, a mounting screw, and a leaf spring. The mounting screw is adjustable and defines a first point of contact with the rock sample. The leaf spring has opposite ends fixed to the inner periphery of the mounting ring. An intermediate portion of the leaf spring projecting radially inward from the ring is formed with a dimple defining a second point of contact with the sample. The first and second points of contact are diametrically opposed to each other. The LVDT is mounted in the ring with its axis parallel to the line of measurement and its core rod received in the dimple of the leaf spring. Any change in the length of the line between the first and second support points is directly communicated to the LVDT. The leaf spring is rigid to completely support lateral forces so that the LVDT is free of all load for improved precision.

  1. Gage for measuring displacements in rock samples

    DOE Patents [OSTI]

    Holcomb, D.J.; McNamee, M.J.

    1985-07-18

    A gage for measuring diametral displacement within a rock sample for use in a rock mechanics laboratory and in the field, comprises a support ring housing a linear variable differential transformer (LVDT), a mounting screw, and a leaf spring. The mounting screw is adjustable and defines a first point of contact with the rock sample. The leaf spring has opposite ends fixed to the inner periphery of the mounting ring. An intermediate portion of the leaf spring projecting radially inward from the ring is formed with a dimple defining a second point of contact with the sample. The first and second points of contact are diametrically opposed to each other. The LVDT is mounted in the ring with its axis parallel to the line of measurement and its core rod received in the dimple of the leaf spring. Any change in the length of the line between the first and second support points is directly communicated to the LVDT. The leaf spring is rigid to completely support lateral forces so that the LVDT is free of all load for improved precision.

  2. Atomic displacements due to spinspin repulsion in conjugated alternant hydrocarbons

    E-Print Network [OSTI]

    Benzi, Michele

    Atomic displacements due to spin­spin repulsion in conjugated alternant hydrocarbons Ernesto-induced atomic displacements in conjugated alt- ernant hydrocarbons. It appears to be responsible alternant hydrocarbons (CAHs) have played a fun- damental role in the development of theoretical chemistry

  3. Performance of T12 and T8 Fluorescent Lamps and Troffers and LED Linear Replacement Lamps CALiPER Benchmark Report

    SciTech Connect (OSTI)

    Myer, Michael; Paget, Maria L.; Lingard, Robert D.

    2009-01-16

    The Department of Energy (DOE) Commercially Available LED Product Evaluation and Reporting (CALiPER) Program was established in 2006 to investigate the performance of light-emitting diode (LED) based luminaires and replacement lamps. To help users better compare LED products with conventional lighting technologies, CALiPER has also performed benchmark research and testing of traditional (i.e., non-LED) lamps and fixtures. This benchmark report addresses standard 4-foot fluorescent lamps (i.e., T12 and T8) and the 2-foot by 4-foot recessed troffers in which they are commonly used. This report also examines available LED replacements for T12 and T8 fluorescent lamps, and their application in fluorescent troffers. The construction and operation of linear fluorescent lamps and troffers are discussed, as well as fluorescent lamp and fixture performance, based on manufacturer data and CALiPER benchmark testing. In addition, the report describes LED replacements for linear fluorescent lamps, and compares their bare lamp and in situ performance with fluorescent benchmarks on a range of standard lighting measures, including power usage, light output and distribution, efficacy, correlated color temperature, and the color rendering index. Potential performance and application issues indicated by CALiPER testing results are also examined.

  4. Diode-Pumped Alkali Laser: A New Combination

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

    commercially available diode arrays enable fast-track development paths to tactical systems, with mass-to-power ratios that far exceed what is possible with today's other...

  5. Plasma-filled diode based on the coaxial gun

    SciTech Connect (OSTI)

    Zherlitsyn, A. A.; Kovalchuk, B. M.; Pedin, N. N.

    2012-10-15

    The paper presents the results of studies of a coaxial gun for a plasma-filled electron diode. Effects of the discharge channel diameter and gun current on characteristics of the plasma and pulse generated in the diode were investigated. The electron beam with maximum energy of {>=}1 MeV at the current of Almost-Equal-To 100 kA was obtained in the experiments with a plasma-filled diode. The energy of Almost-Equal-To 5 kJ with the peak power of {>=}100 GW dissipated in the diode.

  6. Demonstration Assessment of Light-Emitting Diode Parking Structure...

    Office of Scientific and Technical Information (OSTI)

    Parking Structure Lighting at U.S. Department of Labor Headquarters Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode Parking Structure...

  7. Failure Mechanisms and Color Stability in Light-Emitting Diodes during Operation in High- Temperature Environments in Presence of Contamination

    SciTech Connect (OSTI)

    Lall, Pradeep; Zhang, Hao; Davis, J Lynn

    2015-05-26

    The energy efficiency of light-emitting diode (LED) technology compared to incandescent light bulbs has triggered an increased focus on solid state luminaries for a variety of lighting applications. Solid-state lighting (SSL) utilizes LEDs, for illumination through the process of electroluminescence instead of heating a wire filament as seen with traditional lighting. The fundamental differences in the construction of LED and the incandescent lamp results in different failure modes including lumen degradation, chromaticity shift and drift in the correlated color temperature. The use of LED-based products for safety-critical and harsh environment applications necessitates the characterization of the failure mechanisms and modes. In this paper, failure mechanisms and color stability has been studied for commercially available vertical structured thin film LED (VLED) under harsh environment conditions with and without the presence of contaminants. The VLED used for the study was mounted on a ceramic starboard in order to connect it to the current source. Contamination sources studied include operation in the vicinity of vulcanized rubber and adhesive epoxies in the presence of temperature and humidity. Performance of the VLEDs has been quantified using the measured luminous flux and color shift of the VLEDs subjected to both thermal and humidity stresses under a forward current bias of 350 mA. Results indicate that contamination can result in pre-mature luminous flux degradation and color shift in LEDs.

  8. Stimulated emission in GaN-based laser diodes far below the threshold region

    E-Print Network [OSTI]

    2014-01-01

    forward current of light-emitting diodes,” J. Appl. Phys.superluminescent light-emitting diodes based on GaN,” Appl.superluminescent light emitting diode structures,” J. Appl.

  9. LED Holiday Lights: Festive, Safe, and Efficient! | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT PDF iconLED

  10. Concepts for Phosphorescent Organic LEDs at High Brightness ...

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

    Concepts for Phosphorescent Organic LEDs at High Brightness May 24, 2010 at 3pm36-428 Sebastian Reineke Institut fr Angewandte Photophysik, Dresden reineke001 abstract: Organic...

  11. Semiconductor nanowires: from LEDs to Solar Cells | MIT-Harvard...

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

    Semiconductor nanowires: from LEDs to Solar Cells May 4, 2010 at 3pm36-428 Silvija Gradeak Laboratory for Nanophotonics and Electronics, Massachusetts Institute of Technology...

  12. Lighting the Great Outdoors: LEDs in Exterior Applications

    SciTech Connect (OSTI)

    Cook, Tyson D. S.; Bryan, Mary M.; Kinzey, Bruce R.; Myer, Michael

    2008-08-17

    Recent progress in the development of white light LEDs promises great impact by opening up the huge potential for LED illumination in new areas. One such area is general illumination for exterior applications. For example, there are an estimated combined 60.5 million roadway and parking installations in the U.S. These lights account for an estimated 53.3 TWh of electricity usage annually -- nearly 7% of all lighting. If LEDs could provide the same light performance with just 25% greater efficiency, savings of over 13 TWh could be achieved. In 2007, the authors assessed emerging LED lighting technologies in a parking garage and on a city street. The purpose of these tests was to enable a utility to determine whether energy efficiency programs promoting white light LED products might be justified. The results have supported the great promise of LEDs in exterior applications, while also highlighting the barriers that continue to hinder their widespread adoption. Such barriers include 1) inconsistent product quality across manufacturers; 2) lack of key metrics for comparing LEDs to conventional sources; and 3) high upfront cost of LED luminaires compared to conventional luminaires. This paper examines these barriers, ways in which energy-efficiency programs could help to overcome them, and the potential for energy and financial savings from LED lighting in these two exterior applications.

  13. ORNL-led team demonstrates desalination with nanoporous graphene...

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

    Communications 865.576.6448 ORNL-led team demonstrates desalination with nanoporous graphene membrane Researchers created nanopores in graphene (red, and enlarged in the circle...

  14. LEDs Go Ivy League: Princeton University and DOE GATEWAY Demonstrations

    Broader source: Energy.gov [DOE]

    View the video about LED lighting at Princeton University, which has dramatically reduced energy costs in a number of installations around campus. William Evans, electrical engineer, describes the...

  15. REA Refrigerated Display Case LED Lighting Performance Specification...

    Broader source: Energy.gov (indexed) [DOE]

    Retailer Energy Alliances (REA) Project rearefrigdisplayspec.pdf More Documents & Publications CBEA LED Site Lighting Specification - Version 1.3, Released 2152012 Model...

  16. Adopting LED Technology: What Federal Facility Managers Need to Know

    Office of Energy Efficiency and Renewable Energy (EERE)

    This document describes the presentation slides for the "Adopting LED Technology: What Federal Facility Managers Need to Know" webinar that took place on September 11, 2014.

  17. Lighting for Health: LEDs in the New Age of Illumination

    SciTech Connect (OSTI)

    2014-05-01

    DOE Solid-State Lighting program technology fact sheet that provides background on current science and considerations related to LED light and health.

  18. InGaN/GaN tunnel junctions for hole injection in GaN light emitting diodes

    SciTech Connect (OSTI)

    Krishnamoorthy, Sriram, E-mail: krishnamoorthy.13@osu.edu, E-mail: rajan@ece.osu.edu; Akyol, Fatih [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Rajan, Siddharth, E-mail: krishnamoorthy.13@osu.edu, E-mail: rajan@ece.osu.edu [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)

    2014-10-06

    InGaN/GaN tunnel junction contacts were grown using plasma assisted molecular beam epitaxy (MBE) on top of a metal-organic chemical vapor deposition (MOCVD)-grown InGaN/GaN blue (450?nm) light emitting diode. A voltage drop of 5.3?V at 100?mA, forward resistance of 2 × 10{sup ?2} ? cm{sup 2}, and a higher light output power compared to the reference light emitting diodes (LED) with semi-transparent p-contacts were measured in the tunnel junction LED (TJLED). A forward resistance of 5?×?10{sup ?4} ? cm{sup 2} was measured in a GaN PN junction with the identical tunnel junction contact as the TJLED, grown completely by MBE. The depletion region due to the impurities at the regrowth interface between the MBE tunnel junction and the MOCVD-grown LED was hence found to limit the forward resistance measured in the TJLED.

  19. Origin of InGaN/GaN light-emitting diode efficiency improvements using tunnel-junction-cascaded active regions

    SciTech Connect (OSTI)

    Piprek, Joachim, E-mail: piprek@nusod.org [NUSOD Institute LLC, P.O. Box 7204, Newark, Delaware 19714 (United States)

    2014-02-03

    This Letter investigates the efficiency enhancement achieved by tunnel junction insertion into the InGaN/GaN multi-quantum well (MQW) active region of blue light emitting diodes (LEDs). The peak quantum efficiency of such LED exceeds 100%, but the maximum wall-plug efficiency (WPE) hardly changes. However, due to the increased bias, the WPE peaks at much higher input power, i.e., the WPE droop is significantly delayed, and the output power is strongly enhanced. The main physical reason for this improvement lies in the non-uniform vertical carrier distribution typically observed within InGaN MQWs.

  20. Angular distribution of polarized spontaneous emissions and its effect on light extraction behavior in InGaN-based light emitting diodes

    SciTech Connect (OSTI)

    Yuan, Gangcheng; Chen, Xinjuan; Yu, Tongjun, E-mail: tongjun@pku.edu.cn; Lu, Huimin; Chen, Zhizhong; Kang, Xiangning; Wu, Jiejun; Zhang, Guoyi [State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China)

    2014-03-07

    Angular intensity distributions of differently polarized light sources in multiple quantum wells (MQWs) and their effects on extraction behavior of spontaneous emission from light emitting diode (LED) chips have been studied. Theoretical calculation based on k·p approximation, ray tracing simulation and angular electroluminescence measurement were applied in this work. It is found that the electron-hole recombination in the InGaN MQWs produces a spherical distribution of an s-polarized source and a dumbbell-shaped p-polarized source. Light rays from different polarized sources experience different extraction processes, determining the polarization degree of electro-luminescence and extraction efficiency of LEDs.

  1. The photocatalysis of Bi{sub 2}MoO{sub 6} under the irradiation of blue LED

    SciTech Connect (OSTI)

    Sun, Yuanyuan; Wang, Wenzhong Zhang, Ling; Sun, Songmei

    2013-10-15

    Graphical abstract: - Highlights: • ·OH trap and hole sink were involved to investigate the active radicals. • Holes play a more important role in the degradation of RhB. • The ·OH were related to the decomposition of phenol. • The ·O{sub 2}-played a leading role in the photodegradation of phenol. • Blue LED is competitive and promising alternative for the future application. - Abstract: Bi{sub 2}MoO{sub 6} has been reported as a promising photocatalyst in wastewater treatment. The active radicals generated over the Bi{sub 2}MoO{sub 6} during the photocatalytic process were thought to be hydroxyl radical (·OH) but have not been proved. Herein, Bi{sub 2}MoO{sub 6} with nanoplate like morphology was synthesized and its photocatalytic performances in the degradation of rhodamine B (RhB) and phenol as colored and colorless model pollutants respectively were evaluated under the irradiation of blue light emitting diode (LED). The tert-butyl alcohol (TBA) as a ·OH trap and ethylene diamine tetraacetic acid (EDTA) as a hole sink were involved to investigate the main active groups that are generated on Bi{sub 2}MoO{sub 6} and function during the photodegradation of RhB and phenol. In addition, it is a competitive and promising alternative plan to use blue LED as light source for the future practical application in environmental remediation.

  2. High power light emitting diode based setup for photobleaching fluorescent impurities

    E-Print Network [OSTI]

    Kaufman, Laura

    High power light emitting diode based setup for photobleaching fluorescent impurities Tobias K be photobleached before final sample preparation. The instrument consists of high power light emitting diodes

  3. Prediction of Lumen Output and Chromaticity Shift in LEDs Using Kalman Filter and Extended Kalman Filter Based Models

    SciTech Connect (OSTI)

    Lall, Pradeep; Wei, Junchao; Davis, J Lynn

    2014-06-24

    Abstract— Solid-state lighting (SSL) luminaires containing light emitting diodes (LEDs) have the potential of seeing excessive temperatures when being transported across country or being stored in non-climate controlled warehouses. They are also being used in outdoor applications in desert environments that see little or no humidity but will experience extremely high temperatures during the day. This makes it important to increase our understanding of what effects high temperature exposure for a prolonged period of time will have on the usability and survivability of these devices. Traditional light sources “burn out” at end-of-life. For an incandescent bulb, the lamp life is defined by B50 life. However, the LEDs have no filament to “burn”. The LEDs continually degrade and the light output decreases eventually below useful levels causing failure. Presently, the TM-21 test standard is used to predict the L70 life of LEDs from LM-80 test data. Several failure mechanisms may be active in a LED at a single time causing lumen depreciation. The underlying TM-21 Model may not capture the failure physics in presence of multiple failure mechanisms. Correlation of lumen maintenance with underlying physics of degradation at system-level is needed. In this paper, Kalman Filter (KF) and Extended Kalman Filters (EKF) have been used to develop a 70-percent Lumen Maintenance Life Prediction Model for LEDs used in SSL luminaires. Ten-thousand hour LM-80 test data for various LEDs have been used for model development. System state at each future time has been computed based on the state space at preceding time step, system dynamics matrix, control vector, control matrix, measurement matrix, measured vector, process noise and measurement noise. The future state of the lumen depreciation has been estimated based on a second order Kalman Filter model and a Bayesian Framework. Life prediction of L70 life for the LEDs used in SSL luminaires from KF and EKF based models have been compared with the TM-21 model predictions and experimental data.

  4. Ultra Bright LED Light Injection Calibration System for MINOS

    E-Print Network [OSTI]

    B. Anderson; A. Anjomshoaa; P. Dervan; J. A. Lauber; J. Thomas

    1998-10-26

    We describe here a proposal for a light injection calibration system for the MINOS detectors based on ultra bright blue LEDs as the light source. We have shown that these LEDs are bright enough to span over two orders of magnitude in light intensity, commensurate with that expected in a single scintillator strip in the MINOS neutrino detectors.

  5. ECE 466: LED Lighting Systems -Incandescent lightings rise and

    E-Print Network [OSTI]

    Connors, Daniel A.

    ECE 466: LED Lighting Systems - Incandescent lightings rise and demise via government policy - Alternative Fluorescent light sources and compact fluorescent lights (CFL) to incandescents - Alternative LED light sources - Color index as well as Watts to Lumens efficiency available from all three light sources

  6. Low Cost Lithography Tool for High Brightness LED Manufacturing

    SciTech Connect (OSTI)

    Andrew Hawryluk; Emily True

    2012-06-30

    The objective of this activity was to address the need for improved manufacturing tools for LEDs. Improvements include lower cost (both capital equipment cost reductions and cost-ofownership reductions), better automation and better yields. To meet the DOE objective of $1- 2/kilolumen, it will be necessary to develop these highly automated manufacturing tools. Lithography is used extensively in the fabrication of high-brightness LEDs, but the tools used to date are not scalable to high-volume manufacturing. This activity addressed the LED lithography process. During R&D and low volume manufacturing, most LED companies use contact-printers. However, several industries have shown that these printers are incompatible with high volume manufacturing and the LED industry needs to evolve to projection steppers. The need for projection lithography tools for LED manufacturing is identified in the Solid State Lighting Manufacturing Roadmap Draft, June 2009. The Roadmap states that Projection tools are needed by 2011. This work will modify a stepper, originally designed for semiconductor manufacturing, for use in LED manufacturing. This work addresses improvements to yield, material handling, automation and throughput for LED manufacturing while reducing the capital equipment cost.

  7. Appraisers Project Plan: Wireless Controls and Retrofit LED Lighting Demonstration

    Broader source: Energy.gov [DOE]

    Appraisers Project Plan: Wireless Controls and Retrofit LED Lighting Demonstration Measurement and Verification Report This report details the measurement and verification tools and methods used to evaluate the effectiveness of wireless lighting controls and LED lighting at the Appraisers Building, a federal office building in San Francisco, CA.

  8. Diode pumped alkali vapor fiber laser

    DOE Patents [OSTI]

    Payne, Stephen A. (Castro Valley, CA); Beach, Raymond J. (Livermore, CA); Dawson, Jay W. (Livermore, CA); Krupke, William F. (Pleasanton, CA)

    2006-07-26

    A method and apparatus is provided for producing near-diffraction-limited laser light, or amplifying near-diffraction-limited light, in diode pumped alkali vapor photonic-band-gap fiber lasers or amplifiers. Laser light is both substantially generated and propagated in an alkali gas instead of a solid, allowing the nonlinear and damage limitations of conventional solid core fibers to be circumvented. Alkali vapor is introduced into the center hole of a photonic-band-gap fiber, which can then be pumped with light from a pump laser and operated as an oscillator with a seed beam, or can be configured as an amplifier.

  9. Diode pumped alkali vapor fiber laser

    DOE Patents [OSTI]

    Payne, Stephen A. (Castro Valley, CA); Beach, Raymond J. (Livermore, CA); Dawson, Jay W. (Livermore, CA); Krupke, William F. (Pleasanton, CA)

    2007-10-23

    A method and apparatus is provided for producing near-diffraction-limited laser light, or amplifying near-diffraction-limited light, in diode pumped alkali vapor photonic-band-gap fiber lasers or amplifiers. Laser light is both substantially generated and propagated in an alkali gas instead of a solid, allowing the nonlinear and damage limitations of conventional solid core fibers to be circumvented. Alkali vapor is introduced into the center hole of a photonic-band-gap fiber, which can then be pumped with light from a pump laser and operated as an oscillator with a seed beam, or can be configured as an amplifier.

  10. Bypass diode for a solar cell

    DOE Patents [OSTI]

    Rim, Seung Bum; Kim, Taeseok; Smith, David D; Cousins, Peter J

    2013-11-12

    Methods of fabricating bypass diodes for solar cells are described. In once embodiment, a method includes forming a first conductive region of a first conductivity type above a substrate of a solar cell. A second conductive region of a second conductivity type is formed on the first conductive region. In another embodiment, a method includes forming a first conductive region of a first conductivity type above a substrate of a solar cell. A second conductive region of a second conductivity type is formed within, and surrounded by, an uppermost portion of the first conductive region but is not formed in a lowermost portion of the first conductive region.

  11. TRICOLOR LIGHT EMITTING DIODE DOT MATRIX DISPLAY SYSTEM WITHAUDIO OUTPUT

    E-Print Network [OSTI]

    Pang, Grantham

    1 TRICOLOR LIGHT EMITTING DIODE DOT MATRIX DISPLAY SYSTEM WITHAUDIO OUTPUT Grantham Pang, Chi emitting diodes; tricolor display; audio communication. I. Introduction This paper relates to a tricolor broadcasting through the visible light rays transmitted by the display panel or assembly. Keywords: light

  12. Indoor positioning algorithm using light-emitting diode visible light

    E-Print Network [OSTI]

    Kavehrad, Mohsen

    Indoor positioning algorithm using light- emitting diode visible light communications Zhou Zhou of Use: http://spiedl.org/terms #12;Indoor positioning algorithm using light-emitting diode visible light. This paper proposes a novel indoor positioning algorithm using visible light communications (VLC

  13. Author's personal copy Perforated diode neutron detector modules fabricated from

    E-Print Network [OSTI]

    Shultis, J. Kenneth

    Author's personal copy Perforated diode neutron detector modules fabricated from high Perforated detectors Perforated diodes a b s t r a c t Compact neutron detectors are being designed that are mass produced from high-purity Si wafers. Each detector has thousands of circular perforations etched

  14. Dislocation-related trap levels in nitride-based light emitting diodes

    SciTech Connect (OSTI)

    Venturi, Giulia; Castaldini, Antonio; Cavallini, Anna

    2014-05-26

    Deep level transient spectroscopy was performed on InGaN/GaN multiple quantum well light emitting diodes (LEDs) in order to determine the effect of the dislocation density on the deep intragap electronic levels. The LEDs were grown by metalorganic vapor phase epitaxy on GaN templates with a high dislocation density of 8 × 10{sup 9} cm{sup ?2} and a low dislocation density of 3 × 10{sup 8} cm{sup ?2}. Three trapping levels for electrons were revealed, named A, A1, and B, with energies E{sub A}???0.04?eV, E{sub A1}???0.13?eV, and E{sub B}???0.54?eV, respectively. The trapping level A has a much higher concentration in the LEDs grown on the template with a high density of dislocations. The logarithmic dependence of the peak amplitude on the bias pulse width for traps A and A1 identifies the defects responsible for these traps as associated with linearly arranged defects. We conclude that traps A and A1 are dislocation-related intragap energy levels.

  15. Quality and Performance of LED Flashlights in Kenya: Common End User Preferences and Complaints

    E-Print Network [OSTI]

    Tracy, Jenny

    2010-01-01

    2008. "Measured Off? Grid LED Lighting System Performance."early manifestation of LED lighting in the developing worldfor off-grid lighting products based on LED technology (

  16. High-power InAs/InAsSbP heterostructure leds for methane spectroscopy ({lambda} {approx} 3.3 {mu}m)

    SciTech Connect (OSTI)

    Astakhova, A. P.; Golovin, A. S.; Il'inskaya, N. D.; Kalinina, K. V.; Kizhayev, S. S., E-mail: serguie@mail.ru; Serebrennikova, O. Yu.; Stoyanov, N. D. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation); Horvath, Zs. J. [Hungarian Academy of Sciences, Research Institute for Technical Physics and Materials Science (Hungary); Yakovlev, Yu. P. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

    2010-02-15

    Two designs of light-emitting diodes (LEDs) based on InAsSbP/InAs/InAsSbP double hetero-structures grown by metal-organic vapor phase epitaxy on p- and n-InAs substrates have been studied. The current-voltage and electroluminescence characteristics of the LEDs are analyzed. It is shown that the LED design with a light-emitting crystal (chip) mounted with the epitaxial layer down on the LED case and emission extracted through the n-InAs substrate provides better heat removal. As a result, the spectral characteristics remain stable at increased injection currents and the quantum efficiency of radiative recombination is higher. The internal quantum efficiency of light-em itting structures with an emission wavelength {lambda} = 3.3-3.4 {mu}m is as high as 22.3%. The optical emission power of the LEDs is 140 {mu}W at a current of 1 A in the quasi-continuous mode and reaches a value of 5.5 mW at a current of 9 A in the pulsed mode.

  17. Evaluation of Metal Halide, Plasma, and LED Lighting Technologies for a Hydrogen Fuel Cell Mobile Light (H 2 LT)

    SciTech Connect (OSTI)

    Miller, L. B.; Donohoe, S. P.; Jones, M. H.; White, W. A.; Klebanoff, L. E.; Velinsky, S. A.

    2015-04-22

    This article reports on the testing and comparison of a prototype hydrogen fuel cell light tower (H2LT) and a conventional diesel-powered metal halide light trailer for use in road maintenance and construction activities. The prototype was originally outfitted with plasma lights and then with light-emitting diode (LED) luminaires. Light output and distribution, lighting energy efficiency (i.e., efficacy), power source thermal efficiency, and fuel costs are compared. The metal halide luminaires have 2.2 and 3.1 times more light output than the plasma and LED luminaires, respectively, but they require more power/lumen to provide that output. The LED luminaires have 1.6 times better light efficacy than either the metal halide or plasma luminaires. The light uniformity ratios produced by the plasma and LED towers are acceptable. The fuel cell thermal efficiency at the power required to operate the plasma lights is 48%, significantly higher than the diesel generator efficiency of 23% when operating the metal halide lights. Due to the increased efficiency of the fuel cell and the LED lighting, the fuel cost per lumen-hour of the H2LT is 62% of the metal halide diesel light tower assuming a kilogram of hydrogen is twice the cost of a gallon of diesel fuel.

  18. Domain wall displacement by remote spin-current injection

    E-Print Network [OSTI]

    Skirdkov, P. N.

    We demonstrate numerically the ability to displace a magnetic domain wall (DW) by remote spin current injection. We consider a long and narrow magnetic nanostripe with a single DW. The spin-polarized current is injected ...

  19. Constant displacement rate experiments and constitutive modeling of asphalt mixtures 

    E-Print Network [OSTI]

    Hariharakumar, Pradeep

    2006-04-12

    The focus of this dissertation is on constant displacment rate experiments on asphalt concrete and on developing continuum models in a general thermo-mechanical setting which will corroborate with the experimental results. Modeling asphalt concrete...

  20. The Vroman effect: a molecular level description of fibrinogen displacement 

    E-Print Network [OSTI]

    Jung, Seung-Yong

    2005-02-17

    this system. The results demonstrate that the protein's ?C domains play the critical role. When fibrinogen is adsorbed to a hydrophilic surface via these moieties, its displacement rate in the presence of human plasma is approximately 170 times faster...

  1. Adsorption, Desorption, and Displacement Kinetics of H2O and...

    Office of Scientific and Technical Information (OSTI)

    CO2. The onset of CO2 displacement by H2O occurs between 65 and 75 K. Authors: Smith, R. Scott ; Li, Zhenjun ; Dohnalek, Zdenek ; Kay, Bruce D. Publication Date:...

  2. A scale model study of displacement ventilation with chilled ceilings

    E-Print Network [OSTI]

    Holden, Katherine J. A. (Katherine Joan Adrienne)

    1995-01-01

    Displacement ventilation is a form of air-conditioning which provides good air quality and some energy savings. The air quality is better than for a conventional mixed ventilation system. The maximum amount of cooling that ...

  3. Key Factors in Displacement Ventilation Systems for Better IAQ 

    E-Print Network [OSTI]

    Wang, X.; Chen, J.; Li, Y.; Wang, Z.

    2006-01-01

    This paper sets up a mathematical model of three-dimensional steady turbulence heat transfer in an air-conditioned room of multi-polluting heat sources. Numerical simulation helps identify key factors in displacement ventilation systems that affect...

  4. Iraq's housing crisis : upgrading settlements for IDPS (internally displaced persons)

    E-Print Network [OSTI]

    Shaikley, Layla Karim

    2013-01-01

    The most recent war in Iraq has resulted in a large wave of internal and external displacement with increased sectarian violence and ethnic tension. Subsequent conflict has exacerbated conditions within the nation and ...

  5. Recovery of oil from fractured reservoirs by gas displacement 

    E-Print Network [OSTI]

    Unneberg, Arild

    1974-01-01

    RECOVERY OF OIL FROM FRACTURED RESERVOIRS BY GAS DISPLACEMENT A Thesis by ARILD UNNE BE RG Submitted to the Graduate College of Texas AlkM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1974... Major Subject: Petroleum Engineering RECOVERY OF OIL FROM FRACTURED RESERVOIRS BY GAS DISPLACEMENT A Thesis by ARILD UNNEBERG Approved as, to style and content by: . ( y (Chairman of Cornrnittee) (Head of Depar nt) / (Membe r) (Member) M b...

  6. Time Displaced Entanglement and Non-Linear Quantum Evolution

    E-Print Network [OSTI]

    T. C. Ralph

    2005-10-06

    We discuss time displaced entanglement, produced by taking one member of a Bell pair on a round trip at relativistic speeds, thus inducing a time-shift between the pair. We show that decoherence with respect to Bell measurements on the pair is predicted. We then study a teleportation protocol, using time displaced entanglement as its resource, in which a time-like loop is apparently formed. The result is non-unitary, non-linear evolution of the teleported state.

  7. A study of oil displacement by carbonated water 

    E-Print Network [OSTI]

    Partovi-Najafabadi, Roohollah

    1968-01-01

    A STUDY OF OIL DISPLACEMENT BY CARBONATED WATER A Thesis by Roohollah Partovi-N. Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE January 1988... Major Subject: Petroleum Fn ineerin A STUDY OF OIL DISPLACEMENT BY CARBONATED WATER A Thesis by Roohollah Partovi-N. Approved as to style and content by: ( irman of mmittee) M mber) (Head of partment) (Member) January 1968 CP9292...

  8. University of Nevada Las Vegas LED Display Engineering

    SciTech Connect (OSTI)

    None

    2010-08-31

    The primary objective of this part of the project is to develop and implement a method that compensates for the inefficiency of the green LED. The proposed engineering solution which will be the backbone of this project will be to use RGBW combination in every pixel to save energy. Two different RGBW geometrical pixel configurations will be implemented and compared against traditional LED configurations. These configurations will be analyzed for energy efficiency while keeping the quality of the display the same. Cost of the addition of white LEDs to displays along with energy cost savings will be presented and analyzed.

  9. Optimized Phosphors for Warm White LED Light Engines

    SciTech Connect (OSTI)

    Setlur, Anant; Brewster, Megan; Garcia, Florencio; Hill, M. Christine; Lyons, Robert; Murphy, James; Stecher, Tom; Stoklosa, Stan; Weaver, Stan; Happek, Uwe; Aesram, Danny; Deshpande, Anirudha

    2012-07-30

    The objective of this program is to develop phosphor systems and LED light engines that have steady-state LED efficacies (using LEDs with a 60% wall-plug efficiency) of 105–120 lm/W with correlated color temperatures (CCT) ~3000 K, color rendering indices (CRI) >85, <0.003 distance from the blackbody curve (dbb), and <2% loss in phosphor efficiency under high temperature, high humidity conditions. In order to reach these goals, this involves the composition and processing optimization of phosphors previously developed by GE in combination with light engine package modification.

  10. National Consortium Supports Cities in Evaluating LED Streetlights

    SciTech Connect (OSTI)

    2013-09-30

    Fact sheet that introduces Municipal Solid-State Street Lighting Consortium, a group of municipalities, utilities, and energy efficiency organizations who are interested in making investments in LED street and area lighting.

  11. LED Watch: Unlocking the Full Potential of Indoor Systems | Department...

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

    Systems june2015ledwatch.pdf More Documents & Publications 2015 ARTICLES What's Next for Solid-State Lighting - February 2015 LED Watch: NGL Tells Us the State of Solid-State...

  12. Laboratory Evaluation of LED T8 Replacement Lamp Products

    SciTech Connect (OSTI)

    Richman, Eric E.; Kinzey, Bruce R.; Miller, Naomi J.

    2011-05-23

    A report on a lab setting analysis involving LED lamps intended to directly replace T8 fluorescent lamps (4') showing light output, power, and economic comparisons with other fluorescent options.

  13. Implementing and Sustaining Operator Led Energy Efficiency Improvements 

    E-Print Network [OSTI]

    Hoyle, A.; Knight, N.; Rutkowski, M.

    2011-01-01

    , to significantly reduce energy consumption, the site must focus on a strategic approach which involves developing, implementing and sustaining a client specific program of energy optimization. We discuss ways of sustaining energy performance through operator led...

  14. Department of Defense led Institutes for Manufacturing Innovation

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

    within 5-7 years 5 DoE and DoD-led Institutes * Established Institutes: - America Makes (Additive Manufacturing)-Established Aug 2012 DoD - Next Gen. Power Electronics Manuf....

  15. Text-Alternative Version: LED Color Stability Webinar

    Broader source: Energy.gov [DOE]

    Michael Royer: All right, welcome ladies and gentleman. I'm Michael Royer of Pacific Northwest National Laboratory, and I'd like to welcome you to today's webinar on LED Color Stability, Ten...

  16. Better than CFL? Dimmable LED Downlights in Hospitality Facilities Webinar

    Broader source: Energy.gov [DOE]

    LEDs represent less than 1% of the installed base of U.S. downlights, which in 2012 numbered about 700 million. In hospitality facilities, past efforts to reduce lighting energy use have mainly...

  17. WEBINAR: LED LIGHTING IN A PERFORMING ARTS BUILDING

    Broader source: Energy.gov [DOE]

    Can LEDs render skin tones and makeup accurately in a dressing room? Can they provide the vertical footcandles in a studio to make dancers' bodies visible, or deliver acting studio lighting to...

  18. Measured Off-Grid LED Lighting System Performance

    E-Print Network [OSTI]

    Granderson, Jessica

    2009-01-01

    Budget: The Economics of Off-Grid Lighting for SmallA. Jacobson. 2007. "The Off-Grid Lighting Market in WesternTesting for Emerging Off-grid White-LED Illumination Systems

  19. Advances in Chip Technology, Packaging Enable White LED Breakthroughs

    Broader source: Energy.gov [DOE]

    Significant advances in chip technology have enabled Cree, Inc.'s Santa Barbara Technology Center to demonstrate white LEDs with record efficacies as high as 74 lumens per watt - on par with...

  20. New GATEWAY Report Monitors LED System Performance in a High...

    Energy Savers [EERE]

    the Yuma (Arizona) Sector Border Patrol Area. Six LED luminaires - installed on three poles as part of a trial installation detailed in a prior GATEWAY report - continue to be...

  1. DOE's Office of Science Sets up Program to Aid Scientists Displaced...

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

    Sets up Program to Aid Scientists Displaced by Hurricane Katrina DOE's Office of Science Sets up Program to Aid Scientists Displaced by Hurricane Katrina September 9, 2005 -...

  2. Integrated LED-based luminare for general lighting

    DOE Patents [OSTI]

    Dowling, Kevin J.; Lys, Ihor A.; Roberge, Brian; Williamson, Ryan C.; Roberts, Ron; Datta, Michael; Mollnow, Tomas; Morgan, Frederick M.

    2013-03-05

    Lighting apparatus and methods employing LED light sources are described. The LED light sources are integrated with other components in the form of a luminaire or other general purpose lighting structure. Some of the lighting structures are formed as Parabolic Aluminum Reflector (PAR) luminaires, allowing them to be inserted into conventional sockets. The lighting structures display beneficial operating characteristics, such as efficient operation, high thermal dissipation, high output, and good color mixing.

  3. White LED Benchmark of 65 Lumens Per Watt Achieved

    Broader source: Energy.gov [DOE]

    Novel chip design and the balance of multiple interrelated design parameters have enabled Cree, Inc.'s Santa Barbara Technology Center to demonstrate white LEDs with efficacies greater than 65 lumens per watt at 350 mA. The results are particularly significant because they were achieved with a pre-production prototype chip using the same package used in Cree's commercially available XLamp® 7090 high power LED, rather than a laboratory device.

  4. An Integrated Solid-State LED Luminaire for General Lighting

    SciTech Connect (OSTI)

    Kevin Dowling; Fritz Morgan Ihor Lys; Mike Datta; Bernd Keller; Thomas Yuan

    2009-03-31

    A strong systems approach to designing and building practical LED-based replacement lamps is lacking. The general method of taking high-performance LEDs and marrying them to standard printed circuit boards, drivers and a heat sink has fallen short of the promise of LED lighting. In this program, a top-down assessment of requirements and a bottom-up reinvention of LED sources, electronics, optics and mechanics have resulted in the highest performance lamp possible. The team, comprised of Color Kinetics, the leaders in LED lighting and Cree, the leaders in LED devices took an approach to reinvent the package, the driver and the overall form and aesthetic of a replacement source. The challenge was to create a new benchmark in LED lighting - the resultant lamp, a PAR38 equivalent, met the light output, color, color quality and efficacy marks set out in the program as well as being dimmable, which is important for market acceptance. The approach combined the use of multiple source die, a chip-on-board approach, a very efficient driver topology, the use of both direct emission and phosphor conversion, and a unique faceted optic to avoid the losses, artifacts and hotspots of lensed approaches. The integral heat sink provided a mechanical base and airflow using a chimney-effect for use in a wide variety of locations and orientations. These research results led to a much better understanding of the system effects of component level technologies. It was clear that best-of-breed sub-system results do not necessarily result in the best end result for the complete system. In doing this work, we did not neglect the practical aspects of these systems. These were not rarified results and commercially impractical but lent themselves to eventual commercial products in the marketplace. The end result - a high performance replacement lamp - will save significant energy while providing a high-quality light source.

  5. LED LUMINAIRE LIFETIME: Recommendations for Testing and Reporting |

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT PDF

  6. LED Lights for All Occasions | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT PDFLED Lights for

  7. LED Luminaire Lifetime: Recommendations for Testing and Reporting

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORT PDFLED Lights

  8. LED Performance Under Tough Conditions | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPA PublicLED ADOPTION REPORT LED ADOPTION REPORTLED Performance

  9. Zinc Oxide and Nitride Nanowire Based Light Emitting Diodes

    E-Print Network [OSTI]

    Lai, Elaine Michelle

    2009-01-01

    wide conversion to LED lighting. It will not be surprisingThese LEDs are bright enough to be used for lighting and areautomotive lighting. A breakdown of the LED market is shown

  10. A study of temperature compensating circuits for voltage references which use negative temperature coefficient zener diodes 

    E-Print Network [OSTI]

    Coleman, Spencer Delano

    1961-01-01

    OF FIGURES Figure Page Zener Diode Voltage vs Current Characteristics. Zener Diode Breakdown Voltage vs Temperature Coefficient . 3a. 1N746 Zener Diode Voltage vs Current Character- istics in Breakdown Region 3b. 1N747 Zener Diode Voltage vs Current... Character- istics in Breakdown Region 10 3c. 1N748 Zener Diode Voltage vs Current Character- istics in Breakdown Region 3d. 1N749 Zener Diode Voltage vs Current Character- istics in Breakdown Region . 12 3e. IN750 Zener Diode Voltage vs Current...

  11. Optical manifold for light-emitting diodes

    DOE Patents [OSTI]

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

    2008-06-03

    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.

  12. Quaternary InGaAsSb Thermophotovoltaic Diodes

    SciTech Connect (OSTI)

    MW Dashiell; JF Beausang; H Ehsani; GJ Nichols; DM Depoy; LR Danielson; P Talamo; KD Rahner; EJ Brown; SR Burger; PM Foruspring; WF Topper; PF Baldasaro; CA Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; J Li; R Martinelli; D Donetski; S Anikeev; G Belenky; S Luryi

    2006-03-09

    In{sub x}Ga{sub 1-x}As{sub y}Sb{sub 1-y} thermophotovoltaic (TPV) diodes were grown lattice-matched to GaSb substrates by Metal Organic Vapor Phase Epitaxy (MOVPE) in the bandgap range of E{sub G} = 0.5 to 0.6eV. InGaAsSb TPV diodes, utilizing front-surface spectral control filters, are measured with thermal-to-electric conversion efficiency and power density of {eta}{sub TPV} = 19.7% and PD =0.58 W/cm{sup 2} respectively for a radiator temperature of T{sub radiator} = 950 C, diode temperature of T{sub diode} = 27 C, and diode bandgap of E{sub G} = 0.53eV. Practical limits to TPV energy conversion efficiency are established using measured recombination coefficients and optical properties of front surface spectral control filters, which for 0.53eV InGaAsSb TPV energy conversion is {eta}{sub TPV} = 28% and PD = 0.85W/cm{sup 2} at the above operating temperatures. The most severe performance limits are imposed by (1) diode open-circuit voltage (VOC) limits due to intrinsic Auger recombination and (2) parasitic photon absorption in the inactive regions of the module. Experimentally, the diode V{sub OC} is 15% below the practical limit imposed by intrinsic Auger recombination processes. Analysis of InGaAsSb diode electrical performance vs. diode architecture indicate that the V{sub OC} and thus efficiency is limited by extrinsic recombination processes such as through bulk defects.

  13. Graphene/GaN diodes for ultraviolet and visible photodetectors

    SciTech Connect (OSTI)

    Lin, Fang; Chen, Shao-Wen; Meng, Jie; Tse, Geoffrey; Fu, Xue-Wen; Xu, Fu-Jun [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Shen, Bo; Liao, Zhi-Min, E-mail: liaozm@pku.edu.cn, E-mail: yudp@pku.edu.cn; Yu, Da-Peng, E-mail: liaozm@pku.edu.cn, E-mail: yudp@pku.edu.cn [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

    2014-08-18

    The Schottky diodes based on graphene/GaN interface are fabricated and demonstrated for the dual-wavelength photodetection of ultraviolet (UV) and green lights. The physical mechanisms of the photoelectric response of the diodes with different light wavelengths are different. For UV illumination, the photo-generated carriers lower the Schottky barrier and increase the photocurrent. For green light illumination, as the photon energy is smaller than the bandgap of GaN, the hot electrons excited in graphene via internal photoemission are responsible for the photoelectric response. Using graphene as a transparent electrode, the diodes show a ?mS photoresponse, providing an alternative route toward multi-wavelength photodetectors.

  14. Understanding Drooping Light Emitting Diodes CEEM | U.S. DOE...

    Office of Science (SC) Website

    Impact Understanding "droop" may result in cheaper, more efficient LEDs; LEDs are more energy efficient, smaller, and longer-lived than incandescent lamps or fluorescent...

  15. Promising Technology: Parking Lot Light-Emitting Diodes with Controls

    Broader source: Energy.gov [DOE]

    LEDs offer several advantages over conventional high intensity discharge (HID) luminaires. LEDs have longer life times, reduced maintenance and operating costs, superior color rendition, and lower energy consumption.

  16. Diode laser welding of aluminum to steel

    SciTech Connect (OSTI)

    Santo, Loredana; Quadrini, Fabrizio; Trovalusci, Federica [University of Rome Tor Vergata, Department of Mechanical Engineering, Via del Politecnico 1, 00133 Rome (Italy)

    2011-05-04

    Laser welding of dissimilar materials was carried out by using a high power diode laser to join aluminum to steel in a butt-joint configuration. During testing, the laser scan rate was changed as well as the laser power: at low values of fluence (i.e. the ratio between laser power and scan rate), poor joining was observed; instead at high values of fluence, an excess in the material melting affected the joint integrity. Between these limiting values, a good aesthetics was obtained; further investigations were carried out by means of tensile tests and SEM analyses. Unfortunately, a brittle behavior was observed for all the joints and a maximum rupture stress about 40 MPa was measured. Apart from the formation of intermeltallic phases, poor mechanical performances also depended on the chosen joining configuration, particularly because of the thickness reduction of the seam in comparison with the base material.

  17. Low-cost laser diode array

    DOE Patents [OSTI]

    Freitas, B.L.; Skidmore, J.A.

    1999-06-01

    A substrate is used to fabricate a low-cost laser diode array. A substrate is machined from an electrically insulative material that is thermally conductive, or two substrates can be bonded together in which the top substrate is electrically as well as thermally conductive. The substrate thickness is slightly longer than the cavity length, and the width of the groove is wide enough to contain a bar and spring (which secures the laser bar firmly along one face of the groove). The spring also provides electrical continuity from the backside of the bar to the adjacent metalization layer on the laser bar substrate. Arrays containing one or more bars can be formed by creating many grooves at various spacings. Along the groove, many bars can be adjoined at the edges to provide parallel electrical conduction. This architecture allows precise and predictable registration of an array of laser bars to a self-aligned microlens array at low cost. 19 figs.

  18. Low-cost laser diode array

    DOE Patents [OSTI]

    Freitas, Barry L. (Livermore, CA); Skidmore, Jay A. (Livermore, CA)

    1999-01-01

    A substrate is used to fabricate a low-cost laser diode array. A substrate is machined from an electrically insulative material that is thermally conductive, or two substrates can be bonded together in which the top substrate is electrically as well as thermally conductive. The substrate thickness is slightly longer than the cavity length, and the width of the groove is wide enough to contain a bar and spring (which secures the laser bar firmly along one face of the groove). The spring also provides electrical continuity from the backside of the bar to the adjacent metalization layer on the laser bar substrate. Arrays containing one or more bars can be formed by creating many grooves at various spacings. Along the groove, many bars can be adjoined at the edges to provide parallel electrical conduction. This architecture allows precise and predictable registration of an array of laser bars to a self-aligned microlens array at low cost.

  19. Microlens frames for laser diode arrays

    DOE Patents [OSTI]

    Skidmore, J.A.; Freitas, B.L.

    1999-07-13

    Monolithic microlens frames enable the fabrication of monolithic laser diode arrays and are manufactured inexpensively with high registration, and with inherent focal length compensation for any lens diameter variation. A monolithic substrate is used to fabricate a low-cost microlens array. The substrate is wet-etched or sawed with a series of v-grooves. The v-grooves can be created by wet-etching, by exploiting the large etch-rate selectivity of different crystal planes. The v-grooves provide a support frame for either cylindrical or custom-shaped microlenses. Because the microlens frames are formed by photolithographic semiconductor batch-processing techniques, they can be formed inexpensively over large areas with precise lateral and vertical registration. The v-groove has an important advantage for preserving the correct focus for lenses of varying diameter. 12 figs.

  20. Mechanical diode: Comparing numerical and experimental characterizations

    SciTech Connect (OSTI)

    Sagartz, M.J.; Segalman, D.; Simmermacher, T.

    1998-02-01

    In this introductory work, joint compliance is studied in both a numerical and experimental setting. A simple bolted interface is used as the test article and compliance is measured for the joint in both compression and in tension. This simple interface is shown to exhibit a strong non-linearity near the transition from compression to tension (or vice-versa). Modeling issues pertaining to numerically solving for the compliance are addressed. It is shown that the model predictions, in spite of convergence being very sensitive to numerical artifacts of the interface model, are in good agreement with experimentally measured strains and joint compliances. The joint behavior is a mechanical analogy to a diode, i.e., in compression, the joint is very stiff, acting almost as a rigid link, while in tension the joint is relatively soft, acting as a spring.

  1. Analysis and Optimization of "Full-Length" Diodes

    SciTech Connect (OSTI)

    Schock, Alfred

    2012-01-19

    A method of analyzing the axial variation of the heat generation rate, temperature, voltage, current density and emitter heat flux in a thermionic converter is described. The method is particularly useful for the case of "long" diodes, each extending over the full length of the reactor core. For a given diode geometry and fuel distribution, the analysis combines a nuclear solution of the axial fission density profile with the iterative solution of four differential equations representing the thermal, electrical, and thermionic interactions within the diode. The digital computer program developed to solve these equations can also perform a design optimization with respect to lead resistance, load voltage, and emitter thickness, for a specified maximum emitter temperature. Typical results are presented, and the use of this analysis for predicting the diode operating characteristics is illustrated.

  2. Thermoelectrically Pumped Light-Emitting Diodes Operating above Unity Efficiency

    E-Print Network [OSTI]

    Santhanam, Parthiban

    A heated semiconductor light-emitting diode at low forward bias voltage Velectrical work to pump heat from the lattice to the photon field. Here the rates of both radiative and nonradiative recombination ...

  3. Giant Thermal Rectification from Polyethylene Nanofiber Thermal Diodes

    E-Print Network [OSTI]

    Zhang, Teng

    2015-01-01

    The realization of phononic computing is held hostage by the lack of high performance thermal devices. Here we show through theoretical analysis and molecular dynamics simulations that unprecedented thermal rectification factors (as large as 1.20) can be achieved utilizing the phase dependent thermal conductivity of polyethylene nanofibers. More importantly, such high thermal rectifications only need very small temperature differences (< 20 oC) across the device, which is a significant advantage over other thermal diodes which need temperature biases on the order of the operating temperature. Taking this into consideration, we show that the dimensionless temperature-scaled rectification factors of the polymer nanofiber diodes range from 12 to 25 - much larger than other thermal diodes (< 8). The polymer nanofiber thermal diode consists of a crystalline portion whose thermal conductivity is highly phase-sensitive and a cross-linked portion which has a stable phase. Nanoscale size effect can be utilized t...

  4. Electro-luminescent cooling: light emitting diodes above unity efficiency

    E-Print Network [OSTI]

    Santhanam, Parthiban

    Experimental demonstration of net electro-luminescent cooling in a diode, or equivalently electroluminescence with wall-plug efficiency greater than unity, had eluded direct observation for more than five decades. We review ...

  5. Bright Light-Emitting Diodes based on Organometal Halide Perovskite

    E-Print Network [OSTI]

    Tan, Zhi-Kuang; Moghaddam, Reza Saberi; Lai, May Ling; Docampo, Pablo; Higler, Ruben; Deschler, Felix; Price, Michael; Sadhanala, Aditya; Pazos, Luis M.; Credgington, Dan; Hanusch, Fabian; Bein, Thomas; Snaith, Henry J.; Friend, Richard H.

    2014-08-03

    temperature and high vacuum processes, rendering them uneconomical for use in large area displays. Here, we report high brightness light-emitting diodes based on solution-processed organometal halide perovskites. We demonstrate electroluminescence in the near...

  6. Demonstration Assessment of Light-Emitting Diode Roadway Lighting...

    Office of Scientific and Technical Information (OSTI)

    New York Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode Roadway Lighting on the FDR Drive in New York, New York This a report about a...

  7. Simulation of localized barrier defects in resonant tunneling diodes 

    E-Print Network [OSTI]

    Stoneberg, Jason Neal

    1995-01-01

    defect assisted tunneling as a possible current mechanism. This study attempts to ascertain the effects of defect potentials in the barriers on current in a simulation of a double barrier resonant tunneling diode. Results indicate that these defects could...

  8. White organic light-emitting diodes: Status and perspective

    E-Print Network [OSTI]

    Reineke, Sebastian

    White organic light-emitting diodes (OLEDs) are ultrathin, large-area light sources made from organic semiconductor materials. Over the past decades, much research has been spent on finding suitable materials to realize ...

  9. Horizontal displacements contribution to tsunami wave energy balance

    E-Print Network [OSTI]

    Dutykh, Denys; Chubarov, Leonid; Shokin, Yuriy

    2010-01-01

    The main reason for the generation of tsunamis is the deformation of the bottom of the ocean caused by an underwater earthquake. Usually, only the vertical bottom motion is taken into accound while the horizontal displacements are neglected. In the present paper we study both the vertical and the horizontal bottom motion while we propose a novel methodology for reconstructing the bottom coseismic displacements field which is transmitted to the free surface using a new three-dimensional Weakly Nonlinear (WN) approach. We pay a special attention to the evolution of kinetic and potential energies of the resulting wave while the contribution of horizontal displacements into wave energy balance is also quantified. Approaches proposed in this study are illustrated on the July 17, 2006 Java tsunami.

  10. Characterization of the deep levels responsible for non-radiative recombination in InGaN/GaN light-emitting diodes

    SciTech Connect (OSTI)

    Meneghini, M. La Grassa, M.; Vaccari, S.; Meneghesso, G.; Zanoni, E.

    2014-03-17

    This paper presents an extensive investigation of the deep levels related to non-radiative recombination in InGaN/GaN light-emitting diodes (LEDs). The study is based on combined optical and deep-level transient spectroscopy measurements, carried out on LEDs with identical structure and with different values of the non-radiative recombination coefficient. Experimental data lead to the following, relevant, results: (i) LEDs with a high non-radiative recombination coefficient have a higher concentration of a trap (labeled as “e{sub 2}”) with an activation energy of 0.7 eV, which is supposed to be located close to/within the active region; (ii) measurements carried out with varying filling pulse duration suggest that this deep level behaves as a point-defect/dislocation complex. The Arrhenius plot of this deep level is critically compared with the previous literature reports, to identify its physical origin.

  11. Ion implanted step recovery diodes - influence of material parameter variations 

    E-Print Network [OSTI]

    Mosman, Thomas Michael

    1974-01-01

    on the successful application of ion implantation in the fabrication of an improved step recovery diode (SRD). At the same time a comprehensive account of the actual device processing will bring to light the problems and difficulties that are ordinarily...ION IMPLANTED STEP RECOVERY DIODES ? INFLUENCE OF MATERIAL PARAMETER VARIATIONS A Thesis by THOMAS MICHAEL MOSMAN Submitted to the Craduate College of Texas ARM University in partial fulfillment of the requirement for the degree of MASTER...

  12. Modular package for cooling a laser diode array

    DOE Patents [OSTI]

    Mundinger, David C. (Stockton, CA); Benett, William J. (Livermore, CA); Beach, Raymond J. (Livermore, CA)

    1992-01-01

    A laser diode array is disclosed that includes a plurality of planar packages and active cooling. The laser diode array may be operated in a long duty cycle, or in continuous operation. A laser diode bar and a microchannel heat sink are thermally coupled in a compact, thin planar package having the laser diode bar located proximate to one edge. In an array, a number of such thin planar packages are secured together in a stacked configuration, in close proximity so that the laser diodes are spaced closely. The cooling means includes a microchannel heat sink that is attached proximate to the laser bar so that it absorbs heat generated by laser operation. To provide the coolant to the microchannels, each thin planar package comprises a thin inlet manifold and a thin outlet manifold connected to an inlet corridor and an outlet corridor. The inlet corridor comprises a hole extending through each of the packages in the array, and the outlet corridor comprises a hole extending through each of the packages in the array. The inlet and outlet corridors are connected to a conventional coolant circulation system. The laser diode array with active cooling has application as an optical pump for high power solid state lasers. Further, it can be incorporated in equipment such as communications devices and active sensors, and in military and space applications, and it can be useful in applications having space constraints and energy limitations.

  13. InGaAsSb thermophotovoltaic diode physics evaluation

    SciTech Connect (OSTI)

    Charache, G.W.; Baldasaro, P.F.; Danielson, L.R. [Lockheed-Martin, Inc., Schenectady, NY (United States)] [and others

    1998-06-01

    The hotside operating temperatures for many projected thermophotovoltaic (TPV) conversion system applications are approximately 1,000 C, which sets an upper limit on the TPV diode bandgap of 0.6 eV from efficiency and power density considerations. This bandgap requirement has necessitated the development of new diode material systems, never previously considered for energy generation. To date, InGaAsSb quaternary diodes grown lattice-matched on GaSb substrates have achieved the highest performance. This report relates observed diode performance to electro-optic properties such as minority carrier lifetime, diffusion length and mobility and provides initial links to microstructural properties. This analysis has bounded potential diode performance improvements. For the 0.52 eV InGaAsSb diodes used in this analysis the measured dark current is 2 {times} 10{sup {minus}5} A/cm{sup 2}, versus a potential Auger limit 1 {times} 10{sup {minus}5} A/cm{sup 2}, a radiative limit of 2 {times} 10{sup {minus}6} A/cm{sup 2} (no photon recycling), and an absolute thermodynamic limit of 1.4 {times} 10{sup {minus}7} A/cm{sup 2}. These dark currents are equivalent to open circuit voltage gains of 20 mV (7%), 60 mV (20%) and 140 mV (45%), respectively.

  14. Criteria for displacement by gas versus water in oil reservoirs 

    E-Print Network [OSTI]

    Piper, Larry Dean

    1981-01-01

    the problem. Croes and SchwarzIp stud1ed the eff1c1ency of water flooding and presented results show1ng effic1ency and water cut as a function of total production for a range of v1scosity rat1os between I and 500. They also used the1r results to compare... of the oil in place at various values of the displac1ng fluid-to-oil ratio (DFOR)* was used as the measure of displacement effic1ency. This procedure was used for two reasons. F1rst, economic limits may be established based on DFOR. Recovery at various...

  15. Displacement of oil from porous material with carbonated water 

    E-Print Network [OSTI]

    Yadav, Jagjit Singh

    1967-01-01

    DISPLACEMENT OF OIL FROM POROUS MATERIAL WITH CARBONATED WATER A Thesis By JAGJIT S. YADAV Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August... 1967 Ma/or Sub)act; Petroleum Engineering DISPLACEMENT OF OIL FROM POROUS MATERIAL WITH CARBONATED WATER A Thesis By JAGJIT ST YADAV Approved as to style and content by: ( ai an of Committee) cZ&-& 3~ ~" (Head of Department) (Member) (Member...

  16. Ultratech Develops an Improved Lithography Tool for LED Wafer Manufacturing

    Broader source: Energy.gov [DOE]

    Ultratech modified an existing lithography tool used for semiconductor manufacturing to better meet the cost and performance targets of the high-brightness LED manufacturing industry. The goal was to make the equipment compatible with the wide range of substrate diameters and thicknesses prevalent in the industry while reducing the capital cost and the overall cost of ownership (COO).

  17. ASPE -Instructor Led Class Vendor Item ID Class Cost

    E-Print Network [OSTI]

    Dennis, Robert G.

    ASPE - Instructor Led Class Vendor Item ID Class Cost 26500 Data Modeling - Onsite Session for up Day Course 1,871.00$ #12;ASPE - Virtual Class Vendor Item ID Class Cost 26500V Data Modeling - Onsite Session for up to 20 Students 9,500.00$ 26500PV Data Modeling - Public Course (price per student) 1

  18. Potential displacement of petroleum imports by solar energy technologies

    SciTech Connect (OSTI)

    DeLeon, P.; Jackson, B.L.; McNown, R.F.; Mahrenholz, G.J.

    1980-05-01

    The United States currently imports close to half of its petroleum requirements. This report delineates the economic, social, and political costs of such a foreign oil dependency. These costs are often intangible, but combined they clearly constitute a greater price for imported petroleum than the strictly economic cost. If we can assume that imported oil imposes significant socioeconomic costs upon the American economy and society, one way to reduce these costs is to develop alternative, domestic energy sources - such as solar energy technologies - which can displace foreign petroleum. The second half of this report estimates that by the year 2000, solar energy technologies can displace 3.6 quads of petroleum. This figure includes solar energy applications in utilities, industrial and agricultural process heat, and transportation. The estimate can be treated as a lower bound; if the United States were to achieve the proposed goal of 20 quads by 2000, the amount of displaced oil probably would be greater. Although all the displaced oil would not be imported, the reduction in imported petroleum would relieve many of the conditions that increase the present cost of foreign oil to the American consumer.

  19. Gamma displacement cross-sections in various materials

    E-Print Network [OSTI]

    Motta, Arthur T.

    Electric (GE) Advanced Boiling Water Reactor (ABWR) indicated that the calculated gamma displacement damage of reactor pressure vessel (RPV) steels in the HFIR reactor (Rehn and Birtcher, 1993; Farrell et al. 1994 there is a large water gap, gamma damage can become comparable to that produced by neutrons, on a straight

  20. Behavior of fullscale concrete segmented pipelines under permanent ground displacements

    E-Print Network [OSTI]

    Michalowski, Radoslaw L.

    Behavior of fullscale concrete segmented pipelines under permanent ground displacements Junhee, Indiana; d Department of Civil Engineering, Merrimack College, MA ABSTRACT Concrete pipelines are one pipelines and eventually lead to joint failures. In order to understand and model the typical failure

  1. Deriving Displacement from a 3 axis Accelerometer Mr. Andrew Blake

    E-Print Network [OSTI]

    Winstanley, Graham

    Deriving Displacement from a 3 axis Accelerometer Mr. Andrew Blake University of Brighton CMIS, Additive 1. Introduction The Nintendo WiiTM, Sony's Playstation 3TM and Microsoft's Xbox 360TM all feature a 1000 seconds is 1,000,000 times greater than that at 1 second. Any small offset errors

  2. Displacement Correction Scheme for MR-Guided Interstitial Laser Therapy

    E-Print Network [OSTI]

    van Vliet, Lucas J.

    Displacement Correction Scheme for MR-Guided Interstitial Laser Therapy S. Suprijanto1 , M.W. Vogel[1,3]. In the absence of motion, MR thermometry based on phase imaging is quite accurate[12 , F.M. Vos1 , H.A. Vrooman2,3 , and A.M. Vossepoel1 1 Pattern Recognition Group, Department

  3. 130 LPW 1000 Lm Warm White LED for Illumination

    SciTech Connect (OSTI)

    Soer, Wouter

    2012-06-14

    An illumination-grade warm-white LED, having correlated color temperature (CCT) between 2700 and 3500 K and capable of producing 1000 lm output at over 130 lm/W at room temperature, has been developed in this program. The high-power warm-white LED is an ideal source for use in indoor and outdoor lighting applications. Over the two year period, we have made the following accomplishments: • Developed a low-cost high-power white LED package and commercialized a series of products with CCT ranging from 2700 to 5700 K under the product name LUXEON M; • Demonstrated a record efficacy of 124.8 lm/W at a flux of 1023 lm, CCT of 3435 K and color rendering index (CRI) over 80 at room temperature in the productized package; • Demonstrated a record efficacy of 133.1 lm/W at a flux of 1015 lm, CCT of 3475 K and CRI over 80 at room temperature in an R&D package. The new high-power LED package is a die-on-ceramic surface mountable LED package. It has four 2 mm2 InGaN pump dice, flip-chip attached to a ceramic submount in a 2x2 array configuration. The submount design utilizes a design approach that combines a high-thermal- conductivity ceramic core for die attach and a low-cost and low-thermal-conductivity ceramic frame for mechanical support and as optical lens carrier. The LED package has a thermal resistance of less than 1.25 K/W. The white LED fabrication also adopts a new batch level (instead of die-by-die) phosphor deposition process with precision layer thickness and composition control, which provides not only tight color control, but also low cost. The efficacy performance goal was achieved through the progress in following key areas: (1) high-efficiency royal blue pump LED development through active region design and epitaxial growth quality improvement (funded by internal programs); (2) improvement in extraction efficiency from the LED package through improvement of InGaN-die-level and package-level optical extraction efficiency; and (3) improvement in phosphor system efficiency by improving the lumen equivalent (LE) and phosphor package efficiency (PPE) through improvement in phosphor-package interactions. The high-power warm-white LED product developed has been proven to have good reliability through extensive reliability tests. The new kilo-lumen package has been commercialized under the product name LUXEON M. As of the end of the program, the LUXEON M product has been released in the following CCT/CRI combinations: 3000K/70, 4000K/70, 5000K/70, 5700K/70, 2700K/80, 3000K/80 and 4000K/80. LM-80 tests for the products with CCTs of 4000 K and higher have reached 8500 hours, and per IESNA TM-21-11 have established an L70 lumen maintenance value of >51,000 hours at A drive current and up to 120 °C board temperature.

  4. Nanospherical-lens lithographical Ag nanodisk arrays embedded in p-GaN for localized surface plasmon-enhanced blue light emitting diodes

    SciTech Connect (OSTI)

    Wei, Tongbo, E-mail: tbwei@semi.ac.cn; Wu, Kui; Sun, Bo; Zhang, Yonghui; Chen, Yu; Huo, Ziqiang; Hu, Qiang; Wang, Junxi; Zeng, Yiping; Li, Jinmin [State Key Laboratory of Solid-State Lighting, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083 (China); Lan, Ding [National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100080 (China)

    2014-06-15

    Large-scale Ag nanodisks (NDs) arrays fabricated using nanospherical-lens lithography (NLL) are embedded in p-GaN layer of an InGaN/GaN light-emitting diode (LED) for generating localized surface plasmon (LSP) coupling with the radiating dipoles in the quantum-well (QWs). Based on the Ag NDs with the controlled surface coverage, LSP leads to the improved crystalline quality of regrowth p-GaN, increased photoluminescence (PL) intensity, reduced PL decay time, and enhanced output power of LED. Compared with the LED without Ag NDs, the optical output power at a current of 350 mA of the LSP-enhanced LEDs with Ag NDs having a distance of 20 and 35 nm to QWs is increased by 26.7% and 31.1%, respectively. The electrical characteristics and optical properties of LEDs with embedded Ag NPs are dependent on the distance of between Ag NPs and QWs region. The LED with Ag NDs array structure is also found to exhibit reduced emission divergence, compared to that without Ag NDs.

  5. Probing Baryogenesis with Displaced Vertices at the LHC

    E-Print Network [OSTI]

    Yanou Cui; Brian Shuve

    2015-07-08

    The generation of the asymmetric cosmic baryon abundance requires a departure from thermal equilibrium in the early universe. In a large class of baryogenesis models, the baryon asymmetry results from the out-of-equilibrium decay of a new, massive particle. We highlight that in the interesting scenario where this particle has a weak scale mass, this out-of-equilibrium condition requires a proper decay length larger than O(1) mm. Such new fields are within reach of the LHC, at which they can be pair produced leaving a distinctive, displaced-vertex signature. This scenario is realized in the recently proposed mechanism of baryogenesis where the baryon asymmetry is produced through the freeze-out and subsequent decay of a meta-stable weakly interacting massive particle ("WIMP baryogenesis"). In analogy to missing energy searches for WIMP dark matter, the LHC is an excellent probe of these new long-lived particles responsible for baryogenesis via the low-background displaced vertex channel. In our paper, we estimate the limits on simplified models inspired by WIMP baryogenesis from two of the most sensitive collider searches by CMS and ATLAS with 8 TeV LHC data. We also estimate the LHC reach at 13 TeV using current strategies, and demonstrate that O(10) improvements in cross-section limits can be achieved by requiring two displaced vertices while lowering kinematic thresholds. For meta-stable WIMPs produced through electroweak interactions, the high luminosity LHC is sensitive to masses up to 2.5 TeV for lifetimes around 1 cm, while for singlets pair-produced through the off-shell-Higgs portal, the LHC is sensitive to production cross sections of O(50) ab for benchmark masses around 150 GeV. Our analysis and proposals also generally apply to displaced vertex signatures from other new physics such as hidden valley models, twin Higgs models and displaced supersymmetry.

  6. Analyzing degradation effects of organic light-emitting diodes via transient optical and electrical measurements

    SciTech Connect (OSTI)

    Schmidt, Tobias D. Jäger, Lars; Brütting, Wolfgang; Noguchi, Yutaka; Ishii, Hisao

    2015-06-07

    Although the long-term stability of organic light-emitting diodes (OLEDs) under electrical operation made significant progress in recent years, the fundamental underlying mechanisms of the efficiency decrease during operation are not well understood. Hence, we present a comprehensive degradation study of an OLED structure comprising the well-known green phosphorescent emitter Ir(ppy){sub 3}. We use transient methods to analyze both electrical and optical changes during an accelerated aging protocol. Combining the results of displacement current measurements with time-resolved investigation of the excited states lifetimes of the emitter allows for a correlation of electrical (e.g., increase of the driving voltage due to trap formation) and optical (e.g., decrease of light-output) changes induced by degradation. Therewith, it is possible to identify two mechanisms resulting in the drop of the luminance: a decrease of the radiative quantum efficiency of the emitting system due to triplet-polaron-quenching at trapped charge carriers and a modified charge carrier injection and transport, as well as trap-assisted non-radiative recombination resulting in a deterioration of the charge carrier balance of the device.

  7. Method and system for homogenizing diode laser pump arrays

    DOE Patents [OSTI]

    Bayramian, Andy J

    2013-10-01

    An optical amplifier system includes a diode pump array including a plurality of semiconductor diode laser bars disposed in an array configuration and characterized by a periodic distance between adjacent semiconductor diode laser bars. The periodic distance is measured in a first direction perpendicular to each of the plurality of semiconductor diode laser bars. The diode pump array provides a pump output propagating along an optical path and characterized by a first intensity profile measured as a function of the first direction and having a variation greater than 10%. The optical amplifier system also includes a diffractive optic disposed along the optical path. The diffractive optic includes a photo-thermo-refractive glass member. The optical amplifier system further includes an amplifier slab having an input face and position along the optical path and separated from the diffractive optic by a predetermined distance. A second intensity profile measured at the input face of the amplifier slab as a function of the first direction has a variation less than 10%.

  8. Observed Minimum Illuminance Threshold for Night Market Vendors in Kenya who use LED Lamps

    E-Print Network [OSTI]

    Johnstone, Peter

    2009-01-01

    of fuel-based and LED lighting technology for business useSelf-reported Impacts of LED Lighting Technology Compared tocost-of- ownership of LED lighting products are an important

  9. Comparative study of field-dependent carrier dynamics and emission kinetics of InGaN/GaN light-emitting diodes grown on (112{sup ¯}2) semipolar versus (0001) polar planes

    SciTech Connect (OSTI)

    Ji, Yun; Liu, Wei; Chen, Rui; Tiam Tan, Swee; Zhang, Zi-Hui; Ju, Zhengang; Zhang, Xueliang; Sun, Handong; Wei Sun, Xiao; Erdem, Talha; Zhao, Yuji; DenBaars, Steven P. E-mail: volkan@stanfordalumni.org; Nakamura, Shuji; Volkan Demir, Hilmi E-mail: volkan@stanfordalumni.org

    2014-04-07

    The characteristics of electroluminescence (EL) and photoluminescence (PL) emission from GaN light-emitting diodes (LEDs) grown on (112{sup ¯}2) semipolar plane and (0001) polar plane have been comparatively investigated. Through different bias-dependent shifting trends observed from the PL and time-resolved PL spectra (TRPL) for the two types of LEDs, the carrier dynamics within the multiple quantum wells (MQWs) region is systematically analyzed and the distinct field-dependent emission kinetics are revealed. Moreover, the polarization induced internal electric field has been deduced for each of the LEDs. The relatively stable emission behavior observed in the semipolar LED is attributed to the smaller polarization induced internal electric field. The study provides meaningful insight for the design of quantum well (QW) structures with high radiative recombination rates.

  10. KLA-Tencor's Inspection Tool Reduces LED Manufacturing Costs

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, KLA-Tencor is developing an improved inspection tool for LED manufacturing that promises to significantly increase overall process yields and minimize expensive waste. The power of the inspection tool lies in optical detection techniques coupled with defect source analysis software to statistically correlate front-end geometric anomalies in the substrate to killer defects on the back end of the manufacturing line, which give rise to an undesirable or unusable end product.

  11. OSRAM SYLVANIA Develops High-Efficiency LED Troffer Replacement

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, OSRAM SYLVANIA is developing a high-efficiency LED 2'x2' troffer replacement that is expected to be commercially available in the spring of 2012 and to be cost-competitive with existing troffers of that size. It is projected to have a light output of up to 4,000 lumens, an efficacy of more than 100 lm/W, and a CCT of 3500K.

  12. LEDS Collaboration in Action Workshop Participant Pack | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas: EnergyKulpsville, Pennsylvania: Energy Resources JumpInformation LEDS

  13. SPECIFYING LED COLOR-TUNABLE PRODUCTS | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURINGEnergy BillsNo. 195 -Rob Robertseere.energy.govFreedom of InformationSPECIFYING LED

  14. Model Specification for LED Roadway Luminaires | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICESpecialAPPENDIX F Wetlandsof Energy Model Repair SpecificationsLED

  15. LED Lights for All Occasions | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICE INDUSTRIALU.S. DepartmentJeanKeyLANL Sustainable Designlightbulbs -LED

  16. Optoelectronic devices based on electrically tunable p–n diodes in a monolayer dichalcogenide

    E-Print Network [OSTI]

    Baugher, Britton W. H.

    The p–n junction is the functional element of many electronic and optoelectronic devices, including diodes, bipolar transistors, photodetectors, light-emitting diodes and solar cells. In conventional p–n junctions, the ...

  17. Green exciplex emission from a bilayer light-emitting diode containing a rare earth ternary complex

    E-Print Network [OSTI]

    Huang, Yanyi

    Green exciplex emission from a bilayer light-emitting diode containing a rare earth ternary complex form 18 October 2001 Abstract A bilayer organic light-emitting diode using a blue-fluorescent yttrium

  18. Injection and transport processes in organic light emitting diodes based on N. Huby a,b

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Injection and transport processes in organic light emitting diodes based on a silole. N. Huby a- conductors in light emitting diodes1 . The different fields of research around the organic electronic allowed

  19. Light extraction enhanced white light-emitting diodes with multi-layered phosphor configuration

    E-Print Network [OSTI]

    You, Jiun Pyng; Tran, Nguyen T.; Shi, Frank G.

    2010-01-01

    and J. K. Kim, “Solid-state light sources getting smart,”power phosphor-converted light-emitting diodes based on III-for phosphor- based white-light-emitting diodes,” Appl.

  20. The design and manufacture of a novel thin-film microelectronic vacuum diode structure 

    E-Print Network [OSTI]

    Mason, Mark E.

    1993-01-01

    be easily expanded to multi-electrode structures, and has application in flat-panel display technology. A process for the manufacture of such a diode is developed herein. Diodes of various sizes are subsequently manufactured and tested. Test results...