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  1. 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 ...

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

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

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

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

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

    Final Report | Department of Energy Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report This report summarizes an LED street lighting assessment project conducted to study the applicability of LED luminaires in a street lighting application. PDF icon emerging_tech_report_led_streetlighting.pdf More Documents & Publications Effective White Light Options for Parking Area

  4. 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: ...

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

    Office of Scientific and Technical Information (OSTI)

    Diode (LED) Parking Lot Lighting in Leavenworth, KS This report describes the process and results of a demonstration of solid-state lighting (SSL) technology in a ...

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

    Office of Scientific and Technical Information (OSTI)

    Diode (LED) Parking Lot Lighting at T.J.Maxx in Manchester, NH Phase I A report describing the process and results of replacing existing parking lot lighting, looking at a LED ...

  7. 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 ...

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

    Office of Scientific and Technical Information (OSTI)

    Roadway Lighting at the I-35W Bridge, Minneapolis, MN Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at the ...

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

    SciTech Connect (OSTI)

    Kinzey, B. R.; Myer, M. A.

    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.

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

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

    Lighting | Department of Energy 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 of observations and results obtained from a lighting demonstration project conducted under a U.S. Department of Energy program. The program supports demonstrations of high-performance solid-state lighting (SSL) products in order to develop empirical data and experience with

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

    SciTech Connect (OSTI)

    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.

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

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

    US Dept of Energy, Office of Scientific and Technical Information Light-emitting Diode (LED) Lighting Research Light-emitting diode (LED) lighting is a type of solid-state lighting that uses a semiconductor to convert electricity to light. LED lighting products are beginning to appear in a wide variety of home, business, and industrial products such as holiday lighting, replacement bulbs for incandescent lamps, street lighting, outdoor area lighting and indoor ambient lighting. Over the past

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

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

    Central Park in New York City (Technical Report) | SciTech Connect Demonstration Assessment of Light-Emitting Diode (LED) Post-Top Lighting at Central Park in New York City Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Post-Top Lighting at 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 existing metal halide

  14. 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

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

    Office of Scientific and Technical Information (OSTI)

    Lighting at Central Park in New York City Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Post-Top Lighting at Central Park in New ...

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

    Office of Scientific and Technical Information (OSTI)

    the Field Museum in Chicago, IL (Technical Report) | SciTech Connect 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 Museum in Chicago, IL This report reviews a demonstration of light-emitting diode (LED) accent lighting compared to halogen (typical) accent lighting in a gallery of the Field Museum in Chicago, IL. Authors: Myer, Michael ; Kinzey, Bruce R.

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

    Office of Scientific and Technical Information (OSTI)

    Central Park in New York City (Technical Report) | SciTech Connect (LED) Post-Top Lighting at Central Park in New York City Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Post-Top Lighting at 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 existing metal halide post-top luminaire. This report reviews the energy

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

    Office of Scientific and Technical Information (OSTI)

    in Leavenworth, KS (Technical Report) | SciTech Connect in Leavenworth, KS Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting in Leavenworth, KS This report describes the process and results of a demonstration of solid-state lighting (SSL) technology in a commercial parking lot lighting application, under the U.S. Department of Energy (DOE) Solid-State Lighting Technology GATEWAY Demonstration Program. The parking lot is for

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

    Office of Scientific and Technical Information (OSTI)

    Site: Lija Loop, Portland, Oregon (Technical Report) | SciTech Connect 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: Lija Loop, Portland, Oregon This report describes the process and results of a demonstration of solid-state lighting (SSL) technology in a residential street lighting application, under the U.S. Department of Energy GATEWAY Solid-State Lighting

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

    Office of Scientific and Technical Information (OSTI)

    at T.J.Maxx in Manchester, NH Phase I (Technical Report) | SciTech Connect at T.J.Maxx in Manchester, NH Phase I Citation Details In-Document 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 replacing existing parking lot lighting, looking at a LED option with occupancy sensors, and conventional alternates. Criteria include payback, light levels, occupant

  1. Demonstration Assessment of Light-Emitting Diode (LED) Accent Lighting at the Field Museum in Chicago, IL

    SciTech Connect (OSTI)

    Myer, Michael; Kinzey, Bruce R.

    2010-12-10

    This report reviews a demonstration of light-emitting diode (LED) accent lighting compared to halogen (typical) accent lighting in a gallery of the Field Museum in Chicago, IL.

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

    Office of Scientific and Technical Information (OSTI)

    the I-35W Bridge, Minneapolis, MN (Technical Report) | SciTech Connect Roadway Lighting at the I-35W Bridge, Minneapolis, MN Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at the I-35W Bridge, Minneapolis, MN This report describes the process and results of a demonstration of solid-state lighting (SSL) technology conducted in 2009 at the recently reconstructed I-35W bridge in Minneapolis, MN. The project was supported under

  3. Demonstration Assessment of Light-Emitting Diode (LED) Post-Top Lighting at Central Park in New York City

    SciTech Connect (OSTI)

    Myer, Michael; Goettel, Russell T.; Kinzey, Bruce R.

    2012-09-30

    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 existing metal halide post-top luminaire. This report reviews the energy savings potential and lighting delivered by the LED post-top luminaires.

  4. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting in Leavenworth, KS

    SciTech Connect (OSTI)

    Myer, Michael; Kinzey, Bruce R.; Curry, Ku'uipo

    2011-05-06

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology in a commercial parking lot lighting application, under the U.S. Department of Energy (DOE) Solid-State Lighting Technology GATEWAY Demonstration Program. The parking lot is for customers and employees of a Walmart Supercenter in Leavenworth, Kansas and this installation represents the first use of the LED Parking Lot Performance Specification developed by the DOE’s Commercial Building Energy Alliance. The application is a parking lot covering more than a half million square feet, lighted primarily by light-emitting diodes (LEDs). Metal halide wall packs were installed along the building facade. This site is new construction, so the installed baseline(s) were hypothetical designs. It was acknowledged early on that deviating from Walmart’s typical design would reduce the illuminance on the site. Walmart primarily uses 1000W pulse-start metal halide (PMH) lamps. In order to provide a comparison between both typical design and a design using conventional luminaires providing a lower illuminance, a 400W PMH design was also considered. As mentioned already, the illuminance would be reduced by shifting from the PMH system to the LED system. The Illuminating Engineering Society of North America (IES) provides recommended minimum illuminance values for parking lots. All designs exceeded the recommended illuminance values in IES RP-20, some by a wider margin than others. Energy savings from installing the LED system compared to the different PMH systems varied. Compared to the 1000W PMH system, the LED system would save 63 percent of the energy. However, this corresponds to a 68 percent reduction in illuminance as well. In comparison to the 400W PMH system, the LED system would save 44 percent of the energy and provide similar minimum illuminance values at the time of relamping. The LED system cost more than either of the PMH systems when comparing initial costs. However, when the life-cycle costs from energy and maintenance were factored into the scenario, the LED system had lower costs at the end of a 10-year analysis period. The LED system had a 6.1 year payback compared to the 1000W PMH system and a 7.5 year payback versus the 400W PMH system. The costs reflect high initial cost for the LED luminaire, plus more luminaires and (subsequently) more poles for the LED system. The other major issue affecting cost effectiveness was that Leavenworth, Kansas has very low electricity costs. The melded rate for this site was $0.056 per kWh for electricity. However, if the national electricity rate of $0.1022/kWh was used the payback would change to between four and five years for the LED system. This demonstration met the GATEWAY requirements of saving energy, matching or improving illumination, and being cost effective. The project also demonstrated that the Commercial Building Energy Alliance (CBEA) specification works in practice. Walmart appreciated having an entire site lighted by LEDs to gain more experience with the technology. Walmart is reviewing the results of the demonstration as they consider their entire real estate portfolio.

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

    SciTech Connect (OSTI)

    Kurose, N. Aoyagi, Y.; Shibano, K.; Araki, T.

    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.

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

    SciTech Connect (OSTI)

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

    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.

  7. 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.

  8. Demonstration Assessment of Light-Emitting Diode (LED) Street Lighting Host Site: Lija Loop, Portland, Oregon

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Myer, Michael

    2009-11-01

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology in a residential street lighting application, under the U.S. Department of Energy GATEWAY Solid-State Lighting Technology Demonstration Program. In this project, eight 100W (nominal) high-pressure sodium cobra head fixtures were replaced with a like number of LED street light luminaires manufactured by Leotek, Inc. The Leotek product achieved an estimated payback in the Lija Loop installation of about 20 years for replacement scenarios and a much shorter 7.6 years for new installations. Much of the associated energy savings (55%) supporting these payback periods, however, were achieved by reducing average horizontal photopic illuminance a similar amount (53%). Examined from a different perspective, the measured performance suggests that the Leotek product is at approximate parity with the HPS cobra head in terms of average delivered photopic illumination for a given power consumption. HPS comprises the second most efficacious street lighting technology available, exceeded only by low pressure sodium (LPS). LPS technology is not considered suitable for most street lighting applications due to its monochromatic spectral output and poor color rendering ability; therefore, this LED product is performing at an efficiency level comparable to its primary competition in this application.

  9. 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.

  10. 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.

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

    SciTech Connect (OSTI)

    Kinzey, B. R.; Myer, M. A.

    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.

  12. 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%.

  13. 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.

  14. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at the I-35W Bridge, Minneapolis, MN

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Myer, Michael

    2009-08-31

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology conducted in 2009 at the recently reconstructed I-35W bridge in Minneapolis, MN. The project was supported under the U.S. Department of Energy (DOE) Solid-State Lighting GATEWAY Technology Demonstration Program. Other participants in the demonstration project included the Minnesota Department of Transportation (Mn/DOT), Federal Highways Administration (FHWA), and BetaLED™ (a division of Ruud Lighting). Pacific Northwest National Laboratory (PNNL) conducted the measurements and analysis of the results. DOE has implemented 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. This document provides information through the initial phase of the I-35W bridge project, up to and including the opening of the bridge to the public and the initial feedback received on the LED lighting installation from bridge users. Initial findings of the evaluation are favorable, with minimum energy savings level of 13% for the LED installation relative to the simulated base case using 250W high-pressure sodium (HPS) fixtures. The LEDs had an average illuminance level of 0.91 foot candles compared to 1.29 fc for the HPS lamps. The LED luminaires cost $38,000 more than HPS lamps, yielding a lengthy payback period, however the bridge contractor had offered to include the LED luminaires as part of the construction package at no additional cost. One potentially significant benefit of the LEDs in this installation is avoiding rolling lane closures on the heavily-traveled interstate bridge for the purpose of relamping the HPS fixtures. Rolling lane closures involve multiple crew members and various maintenance and safety vehicles, diversion of traffic, as well as related administrative tasks (e.g., approvals, scheduling, etc.). Mn/DOT records show an average cost of relamping fixtures along interstate roadways of between $130-150 per pole. The previous bridge saw a lamp mortality rate of approximately 50% every two years, though the new bridge was designed to minimize many of the vibration issues. A voluntary Web-based feedback survey of nearly 500 self-described bridge users showed strong preference for the LED lighting - positive comments outnumbered negative ones by about five-to-one.

  15. 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.

  16. LED lamp

    SciTech Connect (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.

  17. 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.

  18. 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.

  19. LED Directional Lamps | Department of Energy

    Energy Savers [EERE]

    Directional Lamps LED Directional Lamps BTP EERE Solid-State Lighting Program PDF icon led_directional_lamps.pdf More Documents & Publications Energy Savings Estimates of Light Emitting Diodes Recessed LED Downlights General Service LED Lamps

  20. 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.

  1. LedEngin Inc | Open Energy Information

    Open Energy Info (EERE)

    LedEngin Inc Jump to: navigation, search Name: LedEngin, Inc Place: Santa Clara, California Zip: 95054 Product: Developer of Light Emitting Diode (LED) technology for medical and...

  2. 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...

  3. 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...

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

    Office of Scientific and Technical Information (OSTI)

    for parametric failure of LED products has largely been focused on lumen maintenance. ... Subject: Light-emitting diode (LED), color shift, color stability, color maintenance, ...

  5. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting at T.J.Maxx in Manchester, NH Phase I

    SciTech Connect (OSTI)

    Myer, Michael; Goettel, Russell T.

    2010-06-29

    A report describing the process and results of replacing existing parking lot lighting, looking at a LED option with occupancy sensors, and conventional alternates. Criteria include payback, light levels, occupant satisfaction. This report is Phase I of II. Phase I deals with initial installation.

  6. LED Lighting | Department of Energy

    Energy Savers [EERE]

    Electricity & Fuel » Lighting » LED Lighting LED Lighting LED Lighting The light-emitting diode (LED) is one of today's most energy-efficient and rapidly-developing lighting technologies. Quality LED light bulbs last longer, are more durable, and offer comparable or better light quality than other types of lighting. Check out the top 8 things you didn't know about LEDs to learn more. Energy Savings LED is a highly energy efficient lighting technology, and has the potential to fundamentally

  7. LED Lighting | Department of Energy

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

    Electricity & Fuel » Lighting » LED Lighting LED Lighting LED Lighting The light-emitting diode (LED) is one of today's most energy-efficient and rapidly-developing lighting technologies. Quality LED light bulbs last longer, are more durable, and offer comparable or better light quality than other types of lighting. Check out the top 8 things you didn't know about LEDs to learn more. Energy Savings LED is a highly energy efficient lighting technology, and has the potential to fundamentally

  8. LED ADOPTION REPORT | Department of Energy

    Energy Savers [EERE]

    Publications » Market Studies » LED ADOPTION REPORT LED ADOPTION REPORT LED ADOPTION REPORT The DOE report, Adoption of Light-Emitting Diodes in Common Lighting Applications, is the latest in a series analyzing markets where LEDs compete with traditional lighting sources. Report: Adoption of Light-Emitting Diodes in Common Lighting Applications Report Summary Full Infographic The new report reveals a wealth of insights into promising pathways for SSL technology development, providing estimates

  9. LED Lighting Basics | Department of Energy

    Office of Environmental Management (EM)

    LED Lighting Basics LED Lighting Basics August 16, 2013 - 10:07am Addthis Light-Emitting diodes (LEDs) efficiently produce light in a fundamentally different way than any legacy or traditional source of light. LEDs are compound semiconductor devices that produce light when an appropriate electrical current is applied. Applying electrical current causes electrons to flow from the positive side of a diode structure to the negative side causing a chain of complex interactions at an atomic level

  10. LED Lightbulbs

    Broader source: Energy.gov [DOE]

    All of these lightbulbs meet the new energy standards that take effect from 20122014. These LED bulbs use about 75%80% less energy than traditional bulbs.

  11. LED ADOPTION REPORT | Department of Energy

    Energy Savers [EERE]

    ADOPTION REPORT LED ADOPTION REPORT PDF icon Report: Adoption of Light-Emitting Diodes in Common Lighting Applications PDF icon Report Summary PDF icon Full Infographic More Documents & Publications Energy Savings Forecast of Solid-State Lighting in General Illumination Applications 2015 SSL TECHNOLOGY DEVELOPMENT WORKSHOP PRESENTATIONS - Day 1 Energy Savings Estimates of Light Emitting Diodes

  12. LEDs Ready for Takeoff at Louisiana Airport

    Broader source: Energy.gov [DOE]

    About 250 lights along the busy taxiway at Hammond Northshore Regional Airport are being replaced with light-emitting diodes (LEDs) with funds from an Energy Efficiency and Conservation Block Grant (EECBG) from the U.S. Department of Energy.

  13. 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...

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

    SciTech Connect (OSTI)

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

    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.

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

    SciTech Connect (OSTI)

    Paget, M. L.; Lingard, R. D.; Myer, M. A.

    2008-11-01

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

  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. 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.

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

    Broader source: Energy.gov [DOE]

    This project is producing high-efficiency semipolar light-emitting diodes (LEDs) on low-defect bulk gallium nitride (GaN) substrates.

  19. 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 State Lighting Technology Demonstration GATEWAY Program Study Participants: Pacific Northwest National Laboratory U.S. Department of Energy LED Power, Inc. Aztec Energy Partners PECI, Inc. Eugene Water and Electric Board October 2009 Prepared for the U.S. Department of Energy by Pacific Northwest National Laboratory

  20. EECBG Success Story: LEDs Ready for Takeoff at Louisiana Airport

    Broader source: Energy.gov [DOE]

    About 250 lights along the taxiway at Hammond Northshore Regional Airport in Louisiana are being replaced with light-emitting diodes (LEDs) with funds from an Energy Efficiency and Conservation Block Grant (EECBG). Learn more.

  1. Lateral displacement and rotational displacement sensor

    DOE Patents [OSTI]

    Duden, Thomas

    2014-04-22

    A position measuring sensor formed from opposing sets of capacitor plates measures both rotational displacement and lateral displacement from the changes in capacitances as overlapping areas of capacitors change. Capacitances are measured by a measuring circuit. The measured capacitances are provided to a calculating circuit that performs calculations to obtain angular and lateral displacement from the capacitances measured by the measuring circuit.

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

    SciTech Connect (OSTI)

    Lingard, R. D.; Myer, M. A.; Paget, M. L.

    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.

  3. 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.

  4. Data Diode

    Energy Science and Technology Software Center (OSTI)

    2014-11-07

    The Data Diode is a data security technology that can be deployed within an organization's defense-in-depth computer network strategy for information assurance. For internal security, the software creates an environment within the network where an organization's approved users can work freely inside an enclave of protected data, but file transfers out of the enclave is restricted. For external security, once a network intruder has penetrated the network, the intruder is able to "see" the protectedmore » data, but is unable to download the actual data. During the time it takes for the intruder to search for a way around the obstacle created by the Data Diode, the network's intrusion detection technologies can locate and thwart the malicious intent of the intruder. Development of the Data Diode technology was made possible by funding from the Intelligence Advanced Research Projects Activity (IARPA).« less

  5. LED Frequently Asked Questions

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

    as a general light source. As more LED lighting products are introduced on the market, ... Are LEDs ready for general lighting? The number of white-light LED products available on ...

  6. 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.

  7. LED Lightbulbs | Department of Energy

    Energy Savers [EERE]

    File LED lightbulbs - EPS file.

  8. 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.

  9. 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.

  10. 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.

  11. 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 27, 2013 - 12:00am Addthis Jim Brodrick, Lighting Program Manager A Wisconsin-based company is developing an innovative way to reduce manufacturing costs of light-emitting diodes (LEDs). With help from a $2.4 million Energy Department research grant that is matched dollar-for-dollar by the company, researchers at Eaton Corporation in Menomonee Falls, Wisconsin, are creating a manufacturing process that not only

  12. Purchasing Energy-Efficient Commercial and Industrial LED Luminaires |

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

    Department of Energy Commercial and Industrial LED Luminaires Purchasing Energy-Efficient Commercial and Industrial LED Luminaires 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 requirements. Federal laws and requirements mandate that agencies purchase ENERGY STAR-qualified or FEMP-designated products in all product categories covered by these

  13. LED Color Characteristics

    SciTech Connect (OSTI)

    2012-01-01

    Color quality is an important consideration when evaluating LED-based products for general illumination. This fact sheet reviews the basics regarding light and color and summarizes the most important color issues related to white-light LED systems.

  14. 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.

  15. 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, 2014 Contact: Margie Wylie, mwylie@lbl.gov, +1 510 486 7421 Nanostructures half the breadth of a DNA strand could improve the efficiency of light emitting diodes (LEDs), especially in the "green gap," a portion of the spectrum where LED efficiency plunges, simulations at the U.S. Department of Energy's

  16. Cree LED Lighting Solutions Formerly LED Lighting Fixtures LLF...

    Open Energy Info (EERE)

    LED Lighting Solutions Formerly LED Lighting Fixtures LLF Jump to: navigation, search Name: Cree LED Lighting Solutions (Formerly LED Lighting Fixtures (LLF)) Place: Morrisville,...

  17. Precision displacement reference system

    DOE Patents [OSTI]

    Bieg, Lothar F.; Dubois, Robert R.; Strother, Jerry D.

    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.

  18. 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.

  19. 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.

  20. Establishing LED Equivalency

    SciTech Connect (OSTI)

    2011-10-01

    Solid-state lighting program technology fact sheet that provides guidance for comparing products based on LED or other light source technologies.

  1. General Service LED Lamps

    SciTech Connect (OSTI)

    2012-04-01

    Solid-state lighting program technology fact sheet that compares general service incandescent lamps—i.e., light bulbs—to LED and CFL alternatives.

  2. Recessed LED Downlights

    SciTech Connect (OSTI)

    2012-05-01

    Solid-state lighting program technology fact sheet that briefly discusses different LED product types and their performance relative to downlights utilizing traditional lamps.

  3. LED Color Stability

    SciTech Connect (OSTI)

    2014-03-01

    DOE Solid-State Lighting program technology fact sheet that addresses key questions about color stability and color shift in LED lighting applications.

  4. LED MR16 Lamps

    SciTech Connect (OSTI)

    2012-07-01

    Solid-state lighting program technology fact sheet that describes the performance of LED MR16 lamps and discusses electronic compatibility concerns.

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

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

    diodes (LEDs) on low-defect bulk gallium nitride (GaN) substrates. Peak internal quantum efficiency (IQE) values of greater than 80% are achieved over a wide wavelength range...

  6. 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.

  7. 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.

  8. In the OSTI Collections: LEDs | OSTI, US Dept of Energy, Office of

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

    Scientific and Technical Information LEDs User experiences Light-emitting diodes and phosphors Electronics to drive light-emitting diodes Getting the light out of the diode and onto where it's wanted Environmental effects References Research Organizations Patent Assignees Reports Available through OSTI's SciTech Connect Reports Available through OSTI's DOepatents Additional References As "efficiency" is often defined for technology, the efficiency of anything that changes energy

  9. LED Frequently Asked Questions

    SciTech Connect (OSTI)

    2011-05-01

    Solid-state lighting program technology fact sheet that provides an overview of what retailers, energy efficiency advocates, and consumers need to know to make informed LED buying decisions.

  10. 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.

  11. Energy Efficiency of LEDs

    SciTech Connect (OSTI)

    2013-03-01

    Solid-state lighting program technology fact sheet on energy efficiency of LEDs, characterizing the current state of the market and discussing package efficacy, luminaire efficacy, and application efficacy.

  12. 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.

  13. Optical displacement sensor

    DOE Patents [OSTI]

    Carr, Dustin W. (Albuquerque, NM)

    2008-04-08

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

  14. Water displacement mercury pump

    DOE Patents [OSTI]

    Nielsen, Marshall G. (Woodside, CA)

    1985-01-01

    A water displacement mercury pump has a fluid inlet conduit and diffuser, a valve, a pressure cannister, and a fluid outlet conduit. The valve has a valve head which seats in an opening in the cannister. The entire assembly is readily insertable into a process vessel which produces mercury as a product. As the mercury settles, it flows into the opening in the cannister displacing lighter material. When the valve is in a closed position, the pressure cannister is sealed except for the fluid inlet conduit and the fluid outlet conduit. Introduction of a lighter fluid into the cannister will act to displace a heavier fluid from the cannister via the fluid outlet conduit. The entire pump assembly penetrates only a top wall of the process vessel, and not the sides or the bottom wall of the process vessel. This insures a leak-proof environment and is especially suitable for processing of hazardous materials.

  15. Water displacement mercury pump

    DOE Patents [OSTI]

    Nielsen, M.G.

    1984-04-20

    A water displacement mercury pump has a fluid inlet conduit and diffuser, a valve, a pressure cannister, and a fluid outlet conduit. The valve has a valve head which seats in an opening in the cannister. The entire assembly is readily insertable into a process vessel which produces mercury as a product. As the mercury settles, it flows into the opening in the cannister displacing lighter material. When the valve is in a closed position, the pressure cannister is sealed except for the fluid inlet conduit and the fluid outlet conduit. Introduction of a lighter fluid into the cannister will act to displace a heavier fluid from the cannister via the fluid outlet conduit. The entire pump assembly penetrates only a top wall of the process vessel, and not the sides or the bottom wall of the process vessel. This insures a leak-proof environment and is especially suitable for processing of hazardous materials.

  16. 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 quantum yield by immobilizing a preslected chromophore into the rigid framework of a metal-organic framework (MOF); the structure was determined at Beamline 11.3.1. Coating a blue light-emitting diode (LED) with this compound readily generates white light with high luminous efficacy. The new yellow phosphor demonstrates

  17. 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.

  18. high-power LEDs

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

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

  19. LEDS | OpenEI Community

    Open Energy Info (EERE)

    LEDS Home Graham7781's picture Submitted by Graham7781(2017) Super contributor 16 November, 2012 - 11:23 LEDS the focus of Monday's 10 a.m. Town Hall Meeting LEDS Town Hall meeting...

  20. LED Basics | Department of Energy

    Office of Environmental Management (EM)

    SSL Basics » LED Basics LED Basics Unlike incandescent lamps, LEDs are not inherently white light sources. Instead, LEDs emit nearly monochromatic light, making them highly efficient for colored light applications such as traffic lights and exit signs. However, to be used as a general light source, white light is needed. White light can be achieved with LEDs in three ways: Phosphor conversion, in which a phosphor is used on or near the LED to convert the colored light to white light RGB

  1. Advanced Leds | Open Energy Information

    Open Energy Info (EERE)

    Place: Coventry, England, United Kingdom Zip: CV5 6SP Product: Advanced Leds develops LED technology for outdoor lighting, including street lighting applications. Coordinates:...

  2. LEd:JCD

    Office of Legacy Management (LM)

    LEd:JCD TO- 54 k-sour R3scsrck Fouadatlon 0f$..&+0is$tlstituta of TecGJlow Tecmolocy Csilter 10 Zest 35th Stmet ', c!xk3go lo, I3.Umie Atteqtion: MC. R. c. Barrall Gentlemen: Reference is wada to (a) your appUcetio0 of 3awe~ q,' 1959, rrqlacst~alirpn~tonori~200gsr;ls~hi~4~ched oranlm, (b) our a-q.4 of Z'ebmazy 6, lYS9, ke<wthg eddi- tiona1 'L+lmrQdiEp ia 'Support of your applJcatloD, (c) ycxu.r telqr3a of Eqtember 29, 1959, reque5tlng reneval of ~cense sm-49 -vc+biTt cksnga. Since'va kaem

  3. Energy-Department Supported Scientist Receives Nobel Prize for Blue Light LED

    Broader source: Energy.gov [DOE]

    This week, three scientists—two from Japan and one from the United States—received the Nobel Prize in physics for their work on the LED light. The trifecta, Isamu Akasaki, Hiroshi Amano and Shuji Nakamura, earned the prestigious award specifically for their invention of the blue light emitting diode, a game-changer in the history of LED lights. The American scientist, Shuji Nakamura, a pioneer in the lighting industry, is the founder of LED company Soraa, which has a history of working with the Department of Energy—both through EERE and our Advanced Research Projects Agency-Energy (ARPA-E)—on the subject of blue light diodes.

  4. Using LEDs | Department of Energy

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

    Using LEDs Using LEDs With their unique design and performance characteristics-such as directional light emission, compact profile, superior optical control, energy efficiency, breakage resistance, reduced maintenance, and long life-LEDs are well suited to a variety of lighting applications. LED products are most competitive in applications where these performance characteristics outweigh their first-cost disadvantages. Although LED products are finding success in a growing number of

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. LED Performance Under Tough Conditions

    Broader source: Energy.gov [DOE]

    December 2015 LD+A magazine article entitled "LED Performance Under Tough Conditions" discussing three Dept of Energy GATEWAY applications that show how LED luminaires respond to rigorous outdoor environments.

  10. LED Lighting | Department of Energy

    Office of Environmental Management (EM)

    comparable or better light quality than other types of lighting. Check out the top 8 things you didn't know about LEDs to learn more. Energy Savings LED is a highly energy...

  11. Property:DisplacementMeasurement | Open Energy Information

    Open Energy Info (EERE)

    String Description MHK Displacement Measurement Categories Used in FormTemplate MHKSensor & MHKInstrument Allows Values 3-axis (Displacement);2-axis (Displacement);1-axis...

  12. Variable displacement blower

    DOE Patents [OSTI]

    Bookout, Charles C.; Stotts, Robert E.; Waring, Douglass R.; Folsom, Lawrence R.

    1986-01-01

    A blower having a stationary casing for rotatably supporting a rotor assembly having a series of open ended chambers arranged to close against the surrounding walls of the casing. Pistons are slidably mounted within each chamber with the center of rotation of the pistons being offset in regard to the center of rotation of the rotor assembly whereby the pistons reciprocate in the chambers as the rotor assembly turns. As inlet port communicates with the rotor assembly to deliver a working substance into the chamber as the pistons approach a top dead center position in the chamber while an outlet port also communicates with the rotor to exhaust the working substance as the pistons approach a bottom dead center position. The displacement of the blower is varied by adjusting the amount of eccentricity between the center of rotation of the pistons and the center of rotation of the rotor assembly.

  13. LED Lighting Facts®

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

    LED Lighting Facts 2014 Building Technologies Office Peer Review Marc Ledbetter, ... retailers, distributors, lighting designers, specifiers and energy efficiency programs. ...

  14. 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.

  15. 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.

  16. 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.

  17. Poly (p-phenyleneacetylene) light-emitting diodes

    DOE Patents [OSTI]

    Shinar, J.; Swanson, L.S.; Lu, F.; Ding, Y.; Barton, T.J.; Vardeny, Z.V.

    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. 8 figs.

  18. LED Green Power Inc | Open Energy Information

    Open Energy Info (EERE)

    LED Green Power Inc Jump to: navigation, search Name: LED Green Power Inc Place: Santa Cruz, California Zip: 95060 Product: LED fixture and cartridge manufacturer. References: LED...

  19. LED Roundtable Reports | Department of Energy

    Energy Savers [EERE]

    LED Roundtable Reports LED Roundtable Reports PDF icon 2015 LED Core Technology Roundtable Report.pdf PDF icon 2015 LED Product Development and Manufacturing Roundtable Report.pdf...

  20. LED Roundtable Reports | Department of Energy

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

    LED Roundtable Reports LED Roundtable Reports PDF icon 2015 LED Core Technology Roundtable Report.pdf PDF icon 2015 LED Product Development and Manufacturing Roundtable Report.pdf ...

  1. LED Chips and Packaging for 120 LPW SSL Component

    SciTech Connect (OSTI)

    Ibbetson, James

    2009-12-28

    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) 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.

  2. 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.

  3. Employee-Led Safety Committees

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

    Employee-Led Safety Committees 5 Mentoring and Outreach * CHPRC utilizes members of ... Allocation of Resources * Recognition - Establish a recognition budget * Mentoring & ...

  4. Demonstration of LED Street Lighting

    SciTech Connect (OSTI)

    Kinzey, B. R.; Royer, M. P.; Hadjian, M.; Kauffman, R.

    2013-06-01

    GATEWAY program and Municipal Solid-State Street Lighting Consortium report on a demonstration of LED street lighting in Kansas City, MO.

  5. Upgrading Troffer Luminaires to LED

    SciTech Connect (OSTI)

    none,

    2014-01-31

    Solid-state lighting technology fact sheet providing guidance on the various factors to consider when deciding on an LED upgrade for a fluorescent troffer system.

  6. Reporting LED Luminaire Product Performance

    SciTech Connect (OSTI)

    2008-12-01

    This brochure on LED product performance is an outcome of a joint DOE-NGLIA effort to assure and improve the quality of SSL products.

  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. 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.

  9. 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.

  10. LED

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

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

  11. 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.

  12. Borehole optical lateral displacement sensor

    DOE Patents [OSTI]

    Lewis, R.E.

    1998-10-20

    There is provided by this invention an optical displacement sensor that utilizes a reflective target connected to a surface to be monitored to reflect light from a light source such that the reflected light is received by a photoelectric transducer. The electric signal from the photoelectric transducer is then imputed into electronic circuitry to generate an electronic image of the target. The target`s image is monitored to determine the quantity and direction of any lateral displacement in the target`s image which represents lateral displacement in the surface being monitored. 4 figs.

  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. Metacapacitors for LED Lighting: Metacapacitors

    SciTech Connect (OSTI)

    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.

  15. 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.

  16. 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...

  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 PDF icon ledbasics.pdf More Documents & Publications LED Frequently Asked ...

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

    DOE Patents [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.

  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. 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...

  1. General Service LED Lamps | Department of Energy

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

    General Service LED Lamps General Service LED Lamps A U.S. DOE SSL technology fact sheet that compares general service LED light bulbs with incandescent and CFL bulbs. PDF icon led_general-service-lamps.pdf More Documents & Publications LED Directional Lamps Emerging Lighting Technology LED T8 Replacement Lamps

  2. Rotor component displacement measurement system

    DOE Patents [OSTI]

    Mercer, Gary D.; Li, Ming C.; Baum, Charles R.

    2003-05-27

    A measuring system for measuring axial displacement of a tube relative to an axially stationary component in a rotating rotor assembly includes at least one displacement sensor adapted to be located normal to a longitudinal axis of the tube; an insulated cable system adapted for passage through the rotor assembly; a rotatable proximitor module located axially beyond the rotor assembly to which the cables are connected; and a telemetry system operatively connected to the proximitor module for sampling signals from the proximitor module and forwarding data to a ground station.

  3. LED lamp color control system and method

    SciTech Connect (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.

  4. LED lamp power management system and method

    SciTech Connect (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.

  5. light-emitting diode

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

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

  6. Small Area Array-Based LED Luminaire Design

    SciTech Connect (OSTI)

    Thomas Yuan

    2008-01-09

    This report contains a summary of technical achievements during a three-year project to demonstrate high efficiency LED luminaire designs based on small area array-based gallium nitride diodes. Novel GaN-based LED array designs are described, specifically addressing the thermal, optical, electrical and mechanical requirements for the incorporation of such arrays into viable solid-state LED luminaires. This work resulted in the demonstration of an integrated luminaire prototype of 1000 lumens cool white light output with reflector shaped beams and efficacy of 89.4 lm/W at CCT of 6000oK and CRI of 73; and performance of 903 lumens warm white light output with reflector shaped beams and efficacy of 63.0 lm/W at CCT of 2800oK and CRI of 82. In addition, up to 1275 lumens cool white light output at 114.2 lm/W and 1156 lumens warm white light output at 76.5 lm/W were achieved if the reflector was not used. The success to integrate small area array-based LED designs and address thermal, optical, electrical and mechanical requirements was clearly achieved in these luminaire prototypes with outstanding performance and high efficiency.

  7. 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.

  8. Understanding Drooping Light Emitting Diodes CEEM | U.S. DOE Office of

    Office of Science (SC) Website

    Science (SC) Understanding Drooping Light Emitting Diodes CEEM Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights Highlight Archives News & Events Publications History Contact BES Home 04.27.12 Understanding Drooping Light Emitting Diodes CEEM Print Text Size: A A A FeedbackShare Page Scientific Achievement New calculations demonstrate that LED "droop" is dominated by multi-particle interactions. Droop occurs when increasing energy input

  9. LED MR16 Lamps | Department of Energy

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

    report provides detailed analysis of LED MR16 lamp performance, covering basic performance ... Application Summary Report 22: LED MR16 Lamps An initial sample of 27 LED MR16 lamps and 8 ...

  10. Ventilation by stratification and displacement

    SciTech Connect (OSTI)

    Skaaret, E.

    1983-03-01

    Ventilation effectiveness is not one single index which can be used for classifying ventilating systems. It is shown that a system has different effectivenesses depending on the characteristics of the pollution sources. A transient ventilation effectiveness can be used to generally characterize the system behavior during transient conditions. This index is, for a given system, dependent only on the thermal conditions. Using the different concepts of ventilation effectiveness and knowledge of the nature of the diffusion process it is concluded that the mixing principle in ventilation is not the best one. The displacement principle working vertical-up (air supply directly to the zone of occupation) is generally working much better. Density stratification improves the efficiency. Conditions for stable thermal stratification is dealt with. Room heating systems are concluded to be based on the radiant heating principle. A no recirculating displacement solution using a heat exchanger is claimed to be energy efficient. Research work which substantiated the different conclusions is referenced.

  11. LED MR16 Lamps | Department of Energy

    Energy Savers [EERE]

    LED MR16 Lamps LED MR16 Lamps A U.S. DOE Solid-State Lighting Program technology fact sheet on LED MR16 lamps. PDF icon led_mr16-lamps.pdf More Documents & Publications Report 22.1: Photoelectric Performance of LED MR16 Lamps Caliper Retail Lamps Study 3.1: Dimming, Flicker, and Power Quality Characteristics of LED A Lamps Snapshot: MR16 Lamps

  12. LED Lighting Facts | Department of Energy

    Office of Environmental Management (EM)

    LED Lighting Facts LED Lighting Facts LED lighting facts - A Program of the U.S. DOE DOE's LED Lighting Facts® program showcases LED products for general illumination from manufacturers who commit to testing products and reporting performance results according to industry standards. For lighting buyers, designers, and energy efficiency programs, the program provides information essential to evaluating SSL products. Central to the program is the LED Lighting Facts label, which presents

  13. 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:...

  14. 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.

  15. LED Lighting Forecast | Department of Energy

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

    Publications Market Studies LED Lighting Forecast LED Lighting Forecast The DOE report Energy Savings Forecast of Solid-State Lighting in General Illumination Applications ...

  16. Federally Led Accident Investigation Reports | Department of...

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

    Federally Led Accident Investigation Reports Federally Led Accident Investigation Reports Includes Pre-March 2011 Type A Reports June 1, 1999 Type A Accident Investigation Board...

  17. 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 ...

  18. 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 ... U.S. Department of Energy Boston's LED Street Lighting Initiative Joanne Massaro, ...

  19. 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.

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

    SciTech Connect (OSTI)

    Riuttanen, L. Nyknen, H.; Svensk, O.; Suihkonen, S.; Sopanen, M.; Kivisaari, P.; Oksanen, J.; Tulkki, J.

    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.

  1. LED Frequently Asked Questions | Department of Energy

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

    document provides answers to LED frequently asked questions for plant-wide improvements, such as "Are LEDs ready for general lighting?" PDF icon LED Frequently Asked Questions (May 2011) More Documents & Publications LED Frequently Asked Questions Lighting Designer Roundtable on Solid-State Lighting SSL R&D Multi-Year Program Plan

  2. Interferometric fiber optic displacement sensor

    DOE Patents [OSTI]

    Farah, John

    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.

  3. 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.

  4. 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.

  5. Interferometric fiber optic displacement sensor

    DOE Patents [OSTI]

    Farah, John

    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.

  6. Emitron: microwave diode

    DOE Patents [OSTI]

    Craig, G.D.; Pettibone, J.S.; Drobot, A.T.

    1982-05-06

    The invention comprises a new class of device, driven by electron or other charged particle flow, for producing coherent microwaves by utilizing the interaction of electromagnetic waves with electron flow in diodes not requiring an external magnetic field. Anode and cathode surfaces are electrically charged with respect to one another by electron flow, for example caused by a Marx bank voltage source or by other charged particle flow, for example by a high energy charged particle beam. This produces an electric field which stimulates an emitted electron beam to flow in the anode-cathode region. The emitted electrons are accelerated by the electric field and coherent microwaves are produced by the three dimensional spatial and temporal interaction of the accelerated electrons with geometrically allowed microwave modes which results in the bunching of the electrons and the pumping of at least one dominant microwave mode.

  7. 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.

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

    SciTech Connect (OSTI)

    Ton, M. K.; Richman, E. E.; Gilbride, T. L.

    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.

  9. 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.

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

    SciTech Connect (OSTI)

    Rishman, E. E.; Tuenge, J. R.

    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.

  11. 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.

  12. 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.

  13. 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...

  14. Updating the LED Life Cycle Assessment

    Energy Savers [EERE]

    Part 2: LED Manufacturing and Performance 7 Goal of the New Study Review new literature on the life- cycle assessment of LED products. Determine if newer A-19 products...

  15. SemiLEDs | Open Energy Information

    Open Energy Info (EERE)

    SemiLEDs Place: Boise, Idaho Zip: 83702 Product: US-based LED chip maker with Asia manufacturing operations. Coordinates: 43.60698, -116.193409 Show Map Loading map......

  16. 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...

  17. 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.

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

    Energy Savers [EERE]

    Los Angeles, CA Municipal Consortium LED Street Lighting Workshop Presentations and ... Lighting L.M. Seventynine: Who Is He and What Does He Have to Do with LED Street Lighting? ...

  19. LED Roadway Lighting | Department of Energy

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

    Roadway Lighting LED Roadway Lighting PDF icon I-35 Bridge Report, Phase II PDF icon I-35 ... GATEWAY Testing Results for I-35W Bridge Webinar LED Performance Under Tough Conditions

  20. 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...

  1. Successful Selection of LED Streetlight Luminaires: Optimizing...

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

    Optimizing Illumination and Economic Performance Successful Selection of LED Streetlight Luminaires: Optimizing Illumination and Economic Performance This March 6, 2013 ...

  2. LED Lighting: Just the Facts, Please!

    Broader source: Energy.gov [DOE]

    Now there's another arsenal in the toolbox to help consumers find LED lights they can trust: the Lighting Facts™ label.

  3. 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

  4. LED Lighting in a Performing Arts Center

    SciTech Connect (OSTI)

    Wilkerson, A. M.; Abell, T. C.; T., E. Perrin

    2015-07-31

    GATEWAY demonstration report of LED wall washer retrofit lighting at the University of Maryland Clarice Smith Performing Arts Center.

  5. LED North America - Energy Innovation Portal

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

    LED North America Oak Ridge National Laboratory Success Story Details Partner Location Agreement Type Publication Date LED North America Oak Ridge, TN License July 2, 2013 Summary LED North America (LEDNA), founded in 2008, is a company located in Oak Ridge, Tennessee that produces LED alternatives for commercial lighting for applications such as roadways, parking lots, parking garages, and indoor high bay applications. The company is located in Oak Ridge at an incubator facility for the Oak

  6. LED Market Adoption: Status and Trends

    Energy Savers [EERE]

    (lmW) 67 60 CCT (K) 3000 3500 L 70 (hours) 28,000 36,000 Price (unit) 23 30 18 LED Linear Fixtures 19 T12 26% T8 67% T5 7% LED Lamp <1% LED Luminaire <1% 2012 T12 17% T8 72%...

  7. LED Essentials - Technology, Applications, Advantages, Disadvantages |

    Energy Savers [EERE]

    Department of Energy Essentials - Technology, Applications, Advantages, Disadvantages LED Essentials - Technology, Applications, Advantages, Disadvantages 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 and disadvantages, current applications, future potential, and evolving path of LED technology from indicator lights to general illumination. View

  8. 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.

  9. 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.

  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. A Practical Primer to LED Technology | Department of Energy

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

    A Practical Primer to LED Technology A Practical Primer to LED Technology PDF icon A Practical Primer to LED Technology More Documents & Publications LED LUMINAIRE LIFETIME: ...

  12. 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.

  13. 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.

  14. diod - distributed I/O daemon

    Energy Science and Technology Software Center (OSTI)

    2010-01-29

    diod is an I/O forwarding daemon used to improve scalability of file systems on large Linux clusters.

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

    Energy Savers [EERE]

    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 ...

  16. LEDS Events Calendar | Open Energy Information

    Open Energy Info (EERE)

    Page Edit History LEDS Events Calendar (Redirected from CLEAN Calendar) Jump to: navigation, search Home | About | Inventory | Partnerships | Capacity Building | Webinars | Reports...

  17. LEDS Events Calendar | Open Energy Information

    Open Energy Info (EERE)

    Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History LEDS Events Calendar Jump to: navigation, search Home | About | Inventory | Partnerships |...

  18. Demonstration Assessment of LED Parking Structure Lighting

    SciTech Connect (OSTI)

    Kinzey, B. R.; Myer, M. A.

    2013-03-01

    GATEWAY program report on a demonstration of LED parking structure lighting at the U.S. Dept. of Labor headquarters in Washington, DC.

  19. 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.

  20. 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...

  1. Category:LEDS Toolkit | Open Energy Information

    Open Energy Info (EERE)

    meant to support the creation and implementation of a Low Emission Development Strategy. Pages in category "LEDS Toolkit" The following 14 pages are in this category, out of...

  2. 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 ...

  3. Commercial Lighting and LED Lighting Incentives | Department...

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

    Schools Institutional Savings Category Lighting Lighting ControlsSensors Other EE LED Lighting Maximum Rebate Up to 100% of cost; incentives that exceed 5,000 should be...

  4. LED Lighting Facts Snapshot: Indoor Ambient Lighting

    SciTech Connect (OSTI)

    2013-04-01

    LED Lighting Facts Snapshot reports reveal how today's products really perform, drawing on analysis of verified performance data from the program's online product list.

  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. 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.

  7. LED system performance in a trial installation - one year later: Yuma border patrol, Yuma, Arizona

    SciTech Connect (OSTI)

    Wilkerson, Andrea M.; Davis, Robert G.

    2015-04-01

    The Yuma Sector Border Patrol Area is a high temperature and high solar radiation environment, providing an opportunity for the U.S. Department of Energy (DOE) to study thermal effects on outdoor light-emitting diode (LED) luminaires outside of the testing laboratory. Six LED luminaires were installed on three poles on the U.S.- Mexico border in February 2014 as part of a trial installation, which was detailed in a prior GATEWAY report.1 The initial trial installation was intended as a short - term test of six luminaires installed on three poles before proceeding with the complete installation of over 400 luminaires. Unexpected delays in the full installation have prevented the detailed evaluations initially planned, but the six installed LED luminaires continue to be monitored, and over the past year illuminance measurements were recorded initially in February 2014 and again in September 2014 at about 2500 hours of operation and in March 2015 at about 5000 hours of operation.

  8. 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.

  9. 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.

  10. 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 Lumiramic™ 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 Lumileds’ 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.

  11. White-blue electroluminescence from a Si quantum dot hybrid light-emitting diode

    SciTech Connect (OSTI)

    Xin, Yunzi; Nishio, Kazuyuki; Saitow, Ken-ichi

    2015-05-18

    A silicon (Si) quantum dot (QD)-based hybrid inorganic/organic light-emitting diode (LED) was fabricated via solution processing. This device exhibited white-blue electroluminescence at a low applied voltage of 6?V, with 78% of the effective emission obtained from the Si QDs. This hybrid LED produced current and optical power densities 280 and 350 times greater than those previously reported for such device. The superior performance of this hybrid device was obtained by both the prepared Si QDs and the optimized layer structure and thereby improving carrier migration through the hybrid LED and carrier recombination in the homogeneous Si QD layer.

  12. 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.

  13. 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.

  14. Thermoelectric Generator (TEG) Fuel Displacement Potential using

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

    Engine-in-the-Loop and Simulation | Department of Energy (TEG) Fuel Displacement Potential using Engine-in-the-Loop and Simulation Thermoelectric Generator (TEG) Fuel Displacement Potential using Engine-in-the-Loop and Simulation Assessment of fuel savings with thermoelectric generators (TEGs) using detailed model of GM-developed TEG as part of the engine connected to a dynamometer that emulates the rest of the vehicle PDF icon vijayagopal.pdf More Documents & Publications Establishing

  15. Decisions that led to Y-12

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

    Decisions that led to Y-12 Last week we saw the political and organizational changes that led up to the Manhattan Project being created on August 13, 1942. The S-1 Executive Committee created two sites initially, Site X in Tennessee and Site Y in New Mexico. While this was happening the technical and scientific experimentation was already well estab- lished. As early as 1929, Ernest O. Lawrence had invented the cyclotron, a mass spectrom-eter machine that led to the Calutrons (named so for the

  16. A critical review of displacement ventilation

    SciTech Connect (OSTI)

    Yuan, X.; Chen, Q.; Glicksman, L.R.

    1998-10-01

    This paper reviews several aspects of the performance of displacement ventilation: temperature distribution, flow distribution, contaminant distribution, comfort, energy and cost analysis, and design guidelines. Ventilation rate, cooling load, heat source, wall characteristics, space height, and diffuser type have major impacts on the performance of displacement ventilation. Some of the impacts can be estimated by simple equations, but many are still unknown. Based on current findings, displacement ventilation systems without cooled ceiling panels can be used for space with a cooling load up to 13 Btu/(h{center_dot}ft{sup 2}) (40 W/m{sup 2}). Energy consumed by HVAC systems depends on control strategies. The first costs of the displacement ventilation system are similar to those of a mixing ventilation system. The displacement system with cooled ceiling panels can remove a higher cooling load, but the first costs are higher as well. The design guidelines of displacement ventilation developed in Scandinavian countries need to be clarified and extended so that they can be used for US buildings. This paper outlines the research needed to develop design guidelines for US buildings.

  17. 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.

  18. 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...

  19. 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....

  20. LED Outdoor Area Lighting Fact Sheet

    SciTech Connect (OSTI)

    2008-06-01

    This fact sheet reviews the major design and specification concerns for outdoor area lighting, and discusses the potential for LED luminaires to save energy while providing high quality lighting for outdoor areas.

  1. 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...

  2. 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...

  3. LEDS Toolkit and Framework | Open Energy Information

    Open Energy Info (EERE)

    User Interface: Website, Desktop Application Website: en.openei.orgappsLEDS Cost: Free UN Region: Central Asia, Eastern Asia, South-Eastern Asia, "Pacific" is not in the list...

  4. SunLed Technologies | Open Energy Information

    Open Energy Info (EERE)

    Product: Hyderabad-based end-to-end energy efficient lighting solution provider and ESCO focused on LEDs and solar power. Coordinates: 17.6726, 77.5971 Show Map Loading...

  5. LED PAR38 Lamps | Department of Energy

    Energy Savers [EERE]

    PAR38 Lamps LED PAR38 Lamps The following CALiPER reports provide detailed analysis of LED PAR38 lamp performance, covering basic performance characteristics as well as subjective evaluation of beam, shadow, and color quality. Pending reports will offer analysis on flicker, dimming and power quality characteristics; stress testing; and lumen and chromaticity maintenance. These reports are intended to educate the industry on market trends, potential issues, and important areas for improvement.

  6. Testimonials - Partnerships in LED Lighting - Philips Lumileds

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

    Lighting, LLC | Department of Energy LED Lighting - Philips Lumileds Lighting, LLC Testimonials - Partnerships in LED Lighting - Philips Lumileds Lighting, LLC Addthis Text Version The words "Office of Energy Efficiency & Renewable Energy, U.S. Department of Energy, EERE Partnership Testimonials," appear on the screen, followed by "Sunil Thomas, General Manager of San Jose Manufacturing Site, Philips Lumileds Lighting, LLC" and footage of a man sitting in a showcase

  7. Report 23: Photometric Testing of White Tunable LED Luminaires...

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

    Report 23: Photometric Testing of White Tunable LED Luminaires Report 23: Photometric Testing of White Tunable LED Luminaires PDF icon caliper23white-tunable-led-luminaires.pdf ...

  8. LED Luminaire Lifetime: Recommendations For Testing and Reporting...

    Energy Savers [EERE]

    LED Luminaire Lifetime: Recommendations For Testing and Reporting LED Luminaire Lifetime: Recommendations For Testing and Reporting PDF icon LED Luminaire Lifetime: September 2014 ...

  9. SPECIFYING LED COLOR-TUNABLE PRODUCTS | Department of Energy

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

    SPECIFYING LED COLOR-TUNABLE PRODUCTS SPECIFYING LED COLOR-TUNABLE PRODUCTS Specifying LED color-tunable luminaires is dependent on being able to make accurate comparisons between ...

  10. LED Product Development and Manufacturing R&D Roundtable Summary...

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

    LED Product Development and Manufacturing R&D Roundtable Summary LED Product Development and Manufacturing R&D Roundtable Summary PDF icon LED Product Dev and Mfg Roundtable ...

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

    SciTech Connect (OSTI)

    Choong, Vi-En

    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.

  12. 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.

  13. 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.

  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. 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.

  16. 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...

  17. 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.

  18. Advanced Power Electronics for LED Drivers: Advanced Technologies for integrated Power Electronics

    SciTech Connect (OSTI)

    2010-09-01

    ADEPT Project: MIT is teaming with Georgia Institute of Technology, Dartmouth College, and the University of Pennsylvania (UPenn) to create more efficient power circuits for energy-efficient light-emitting diodes (LEDs) through advances in 3 related areas. First, the team is using semiconductors made of high-performing gallium nitride grown on a low-cost silicon base (GaN-on-Si). These GaN-on-Si semiconductors conduct electricity more efficiently than traditional silicon semiconductors. Second, the team is developing new magnetic materials and structures to reduce the size and increase the efficiency of an important LED power component, the inductor. This advancement is important because magnetics are the largest and most expensive part of a circuit. Finally, the team is creating an entirely new circuit design to optimize the performance of the new semiconductors and magnetic devices it is using.

  19. Assessing the Performance of 5mm White LED Light Sources forDeveloping-Country Applications

    SciTech Connect (OSTI)

    Mills, Evan

    2007-05-03

    Some white light-emitting diode (LED) light sources haverecently attained levels of efficiency and cost that allow them tocompete with fluorescent lighting for off-grid applications in thedeveloping world. Additional attributes (optics, size, ruggedness, andservice life) make them potentially superior products. Enormousreductions in energy use and greenhouse-gas emissions are thus possible,and system costs can be much lower given the ability to downsize thecharging and energy storage components compared to a fluorescentstrategy. However, there is a high risk of "market-spoiling" if inferiorproducts are introduced and result in user dissatisfaction. Completesystems involve the integration of light sources and optics, energysupply, and energy storage. A natural starting point for evaluatingproduct quality is to focus on the individual light sources. This reportdescribes testing results for batches of 10 5mm white LEDs from 26manufacturers. Efficacies and color properties are presented.

  20. Memorandum of Decision: Withdrawal of LED Lighting Waiver | Department...

    Office of Environmental Management (EM)

    LED Lighting Waiver Memorandum of Decision: Withdrawal of LED Lighting Waiver novemberdecisionwithdraw More Documents & Publications Nationwide Nonavailability Waiver: November...

  1. Pittsburgh LED Street Lighting Research Project Performance Criteria

    Broader source: Energy.gov [DOE]

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

  2. Next-Generation LED Package Architectures Enabled by Thermally...

    Energy Savers [EERE]

    LED Package Architectures Enabled by Thermally Conductive Transparent Encapsulants Next-Generation LED Package Architectures Enabled by Thermally Conductive Transparent ...

  3. LED COLOR-TUNABLE PRODUCTS | Department of Energy

    Office of Environmental Management (EM)

    CALiPER Testing » Application Reports » LED COLOR-TUNABLE PRODUCTS LED COLOR-TUNABLE PRODUCTS UNDERSTANDING, LED Color-Tunable Products SPECIFYING, LED Color-Tunable Products CONTROLLING, LED Color-Tunable Products TESTING, LED Color-Tunable Products Color-tunable LED luminaires are a nascent and growing product category. Beyond the inherent energy efficiency of LEDs, these luminaires offer other potential benefits including improved health and well-being, increased productivity, enhanced mood

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

    SciTech Connect (OSTI)

    Wang, Hongtao; Salthouse, Christopher D.; Qi, Ying; Mountziaris, T. J.; Chemical Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003

    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 μM. 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. Impact of photonic crystals on LED light extraction efficiency: approaches and limits to vertical structure designs

    SciTech Connect (OSTI)

    Matioli, Elison; Weisbuch, Claude

    2010-08-19

    The enhancement of the extraction efficiency in light emitting diodes (LEDs) through the use of photonic crystals (PhCs) requires a structure design that optimizes the interaction of the guided modes with the PhCs. The main optimization parameters are related to the vertical structure of the LED, such as the thickness of layers, depth of the PhCs, position of the quantum wells as well as the PhC period and fill factor. We review the impact of the vertical design of different approaches of PhC LEDs through a theoretical and experimental standpoint, assessing quantitatively the competing mechanisms that act over each guided mode. Three approaches are described to overcome the main limitation of LEDs with surface PhCs, i.e. the insufficient interaction of low order guided modes with the PhCs. The introduction of an AlGaN confining layer in such structure is shown to be effective in extracting a fraction of the optical energy of low order modes; however, this approach is limited by the growth of the lattice mismatched AlGaN layer on GaN. The second approach, based on thin-film LEDs with PhCs, is limited by the presence of an absorbing reflective metal layer close to the guided modes that plays a major role in the competition between PhC extraction and metal dissipation. Finally, we demonstrate both experimentally and theoretically the superior extraction of the guided light in embedded PhC LEDs due to the higher interaction between all optical modes and the PhCs, which resulted in a close to unity extraction efficiency for this device. The use of high-resolution angle-resolved measurements to experimentally determine the PhC extraction parameters was an essential tool for corroborating the theoretical models and quantifying the competing absorption and extraction mechanisms in LEDs.

  6. 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.

  7. LED structure with enhanced mirror reflectivity

    SciTech Connect (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.

  8. 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...

  9. Semiconductor diode with external field modulation

    DOE Patents [OSTI]

    Nasby, Robert D. (Albuquerque, NM)

    2000-01-01

    A non-destructive-readout nonvolatile semiconductor diode switching device that may be used as a memory element is disclosed. The diode switching device is formed with a ferroelectric material disposed above a rectifying junction to control the conduction characteristics therein by means of a remanent polarization. The invention may be used for the formation of integrated circuit memories for the storage of information.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Final decisions that led to Y-12

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

    decisions that led to Y-12 As we have seen earlier in this series, Ernest O. Lawrence and his University of California Radiation Lab in Berkeley was the center for research using cyclotrons to separate uranium 235 from natural uranium in machines referred to as Calutrons. These newly designed machines were named for CALifornia University CycloTRONS. While the use of mass spectrometry had been known and used since 1918, this application on the scale Lawrence was proposing was going way beyond

  15. 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.

  16. Displacing Natural Gas Consumption and Lowering Emissions

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

    Combustion System for Refinery and Chemical Plant Process Heaters ADVANCED MANUFACTURING OFFICE Displacing Natural Gas Consumption and Lowering Emissions By enabling process heaters to utilize opportunity gaseous fuels with a fuel-flexible combustion system, this technol- ogy lowers carbon and nitrogen oxide (NO x ) emissions and reduces energy costs for industry. Introduction The refning and chemical sectors account for more than 40% of total industrial natural gas use. Prior to the completion

  17. 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.

  18. LED intense headband light source for fingerprint analysis

    DOE Patents [OSTI]

    Villa-Aleman, Eliel

    2005-03-08

    A portable, lightweight and high-intensity light source for detecting and analyzing fingerprints during field investigation. On-site field analysis requires long hours of mobile analysis. In one embodiment, the present invention comprises a plurality of light emitting diodes; a power source; and a personal attachment means; wherein the light emitting diodes are powered by the power source, and wherein the power source and the light emitting diodes are attached to the personal attachment means to produce a personal light source for on-site analysis of latent fingerprints. The present invention is available for other applications as well.

  19. Challenges in LED Research and Development | Department of Energy

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

    LED Research and Development Challenges in LED Research and Development View the video about LED lighting technology, where it is headed, and the DOE's role in its continued R&D

  20. A Statistical Method Analyzing LED Lumen Depreciation and Projecting LED Life

    SciTech Connect (OSTI)

    Qiao, Hong; Pulsipher, Trenton C.; Hathaway, John E.; Richman, Eric E.; Radkov, Emil

    2010-05-30

    There is a strong need for a method to represent the potential life of LED products as a critical part of design decisions including cost-effectiveness analysis. The IES LM-80 test method is in place to collect lumen depreciation data but it does not provide for estimation of future long term depreciation. Separate estimation methods are being considered (TM-21) and this paper describes the analysis of a series of LED degradation models and subsequent development of an estimation method. The work involves analysis of a set of engineering models to determine their applicability and define a structure for their use in LED lumen output life based on a lumen output level such as the L70 metric. The analysis has provided valuable information on methods effectively estimating LED life time, and impacts of measurement uncertainties, test duration, interval and other test conditions on selecting degradation models and LED life time projection. A set of guidelines are recommended to estimate LED life from data obtained using the current LM-80 test method.

  1. LEDS Collaboration in Action Workshop Attendee List | Open Energy...

    Open Energy Info (EERE)

    LEDS Collaboration in Action Workshop Attendee List (Redirected from LEDS Collaboration in Action Workshop Participating Countries) Jump to: navigation, search Low Emission...

  2. 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...

  3. Exterior LED Lighting Projects at Princeton University | Department...

    Energy Savers [EERE]

    Exterior LED Lighting Projects at Princeton University Exterior LED Lighting Projects at Princeton University 2015gatewayprinceton-exterior.pdf gatewayprinceton-exteriorbrief.p...

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

    Office of Scientific and Technical Information (OSTI)

    Report: Demonstration of LED Street Lighting in Kansas City, MO Citation Details In-Document Search Title: Demonstration of LED Street Lighting in Kansas City, MO Nine different ...

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

    Office of Scientific and Technical Information (OSTI)

    of LED Roadway Lighting on the Golden Gate Bridge Citation Details In-Document Search Title: Technical Feasibility Assessment of LED Roadway Lighting on the Golden Gate ...

  6. Guanquan Shandong Photoelectric Technology aka United LED Corporation...

    Open Energy Info (EERE)

    Guanquan Shandong Photoelectric Technology aka United LED Corporation Jump to: navigation, search Name: Guanquan (Shandong) Photoelectric Technology (aka United LED Corporation)...

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

    Office of Environmental Management (EM)

    REA Refrigerated Display Case LED Lighting Performance Specification REA Refrigerated Display Case LED Lighting Performance Specification A Retailer Energy Alliances (REA) Project ...

  8. Member Case Studies: LED Street Lighting Programs in Algona ...

    Energy Savers [EERE]

    Member Case Studies: LED Street Lighting Programs in Algona (IA), Asheville (NC), and Boston (MA) Member Case Studies: LED Street Lighting Programs in Algona (IA), Asheville (NC), ...

  9. New GATEWAY Report Monitors LED System Performance in a High...

    Office of Environmental Management (EM)

    GATEWAY Report Monitors LED System Performance in a High-Temperature Environment New GATEWAY Report Monitors LED System Performance in a High-Temperature Environment May 11, 2015 - ...

  10. Energy Department Announces New University-Led Projects to Create...

    Office of Environmental Management (EM)

    University-Led Projects to Create More Efficient, Lower Cost Concentrating Solar Power Systems Energy Department Announces New University-Led Projects to Create More Efficient, ...

  11. High Impact Technology HQ - Results - LED Troffer, Cove (linear...

    Energy Savers [EERE]

    HQ - Results - LED Troffer, Cove (linear) and Downlight Retrofit Kits: Princeton Icahn Laboratory High Impact Technology HQ - Results - LED Troffer, Cove (linear) and Downlight ...

  12. NETL-Led Laboratory-Industry-Academia Collaboration Is Accelerating...

    Office of Environmental Management (EM)

    NETL-Led Laboratory-Industry-Academia Collaboration Is Accelerating Carbon-Capture Technologies NETL-Led Laboratory-Industry-Academia Collaboration Is Accelerating Carbon-Capture ...

  13. LED Efficacy: What America Stands to Gain | Department of Energy

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

    Efficacy: What America Stands to Gain LED Efficacy: What America Stands to Gain PDF icon LED Efficacy-What America Stands to Gain November 2015.pdf

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

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

    of LED penetration in 10 lighting applications, as well as the potential energy savings if each of these applications had switched completely to the best available LED ...

  15. LED Provides Effective and Efficient Parking Area Lighting at...

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

    LED Provides Effective and Efficient Parking Area Lighting at the NAVFAC Engineering Service Center LED Provides Effective and Efficient Parking Area Lighting at the NAVFAC ...

  16. Consortium Led by University of California, Berkeley Awarded...

    National Nuclear Security Administration (NNSA)

    Consortium Led by University of California, Berkeley Awarded 25M NNSA Grant for Nuclear ... Home Library Press Releases Consortium Led by University of California, Berkeley ... ...

  17. LEDs Go Ivy League: Princeton's Dillon Gymnasium | Department...

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

    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 ...

  18. Solid State Lighting LED Core Technology R&D Roundtable

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

    The document should be referenced as: DOE SSL Program, "Solid State Lighting LED Core Technology R&D Roundtable," November 2015. Authors Monica Hansen LED Lighting Advisors Nnamnor ...

  19. Analysis Led Intake Port Development | Department of Energy

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

    Led Intake Port Development Analysis Led Intake Port Development 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters PDF icon 2005deerfuchinoue.pdf ...

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

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

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

  1. 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?

  2. 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...

  3. CONTROLLING LED COLOR-TUNABLE PRODUCTS | Department of Energy

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

    CONTROLLING LED COLOR-TUNABLE PRODUCTS CONTROLLING LED COLOR-TUNABLE PRODUCTS photo of a conference room. Controlling color-tunable luminaires can be challenging for specifiers,...

  4. Arbitrary waveform generator to improve laser diode driver performance

    DOE Patents [OSTI]

    Fulkerson, Jr, Edward Steven

    2015-11-03

    An arbitrary waveform generator modifies the input signal to a laser diode driver circuit in order to reduce the overshoot/undershoot and provide a "flat-top" signal to the laser diode driver circuit. The input signal is modified based on the original received signal and the feedback from the laser diode by measuring the actual current flowing in the laser diode after the original signal is applied to the laser diode.

  5. 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).

  6. 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.

  7. 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).

  8. 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.

  9. 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.

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

    Broader source: Energy.gov [DOE]

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

  11. 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.

  12. Use of Occupancy Sensors in LED Parking Lot and Garage Applications: Early Experiences

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Myer, Michael; Royer, Michael P.; Sullivan, Greg P.

    2012-11-07

    Occupancy sensor systems are gaining traction as an effective technological approach to reducing energy use in exterior commercial lighting applications. Done correctly, occupancy sensors can substantially enhance the savings from an already efficient lighting system. However, this technology is confronted by several potential challenges and pitfalls that can leave a significant amount of the prospective savings on the table. This report describes anecdotal experiences from field installations of occupancy sensor controlled light-emitting diode (LED) lighting at two parking structures and two parking lots. The relative levels of success at these installations reflect a marked range of potential outcomes: from an additional 76% in energy savings to virtually no additional savings. Several issues that influenced savings were encountered in these early stage installations and are detailed in the report. Ultimately, care must be taken in the design, selection, and commissioning of a sensor-controlled lighting installation, else the only guaranteed result may be its cost.

  13. 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.

  14. Model Specification for LED Roadway Luminaires | Department of Energy

    Energy Savers [EERE]

    Research & Development » Technology Application R&D » Municipal Consortium » Resources » Model Specification for LED Roadway Luminaires Model Specification for LED Roadway Luminaires The DOE Municipal Solid-State Street Lighting Consortium's Model Specification for LED Roadway Luminaires enables cities, utilities, and other state and local agencies to assemble effective bid documents for LED street lighting products. The original version of the Model Specification for LED Roadway

  15. LED T8 Replacement Lamps | Department of Energy

    Energy Savers [EERE]

    LED T8 Replacement Lamps LED T8 Replacement Lamps This documents provides an overview of LED T8 replacement lamps and helps define a reasonable minimum performance level for the purpose of plant-wide improvement. PDF icon LED T8 Replacement Lamps (April 2010) More Documents & Publications Emerging Lighting Technology General Service LED Lamps Guiding Market Introduction of High-Performance SSL Products

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Optical inverse-square displacement sensor

    DOE Patents [OSTI]

    Howe, Robert D.; Kychakoff, George

    1989-01-01

    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 ##EQU1##

  1. Development of Advanced LED Phosphors by Spray-based Processes for Solid State Lighting

    SciTech Connect (OSTI)

    Cabot Corporation

    2007-09-30

    The overarching goal of the project was to develop luminescent materials using aerosol processes for making improved LED devices for solid state lighting. In essence this means improving white light emitting phosphor based LEDs by improvement of the phosphor and phosphor layer. The structure of these types of light sources, displayed in Figure 1, comprises of a blue or UV LED under a phosphor layer that converts the blue or UV light to a broad visible (white) light. Traditionally, this is done with a blue emitting diode combined with a blue absorbing, broadly yellow emitting phosphor such as Y{sub 3}Al{sub 5}O{sub 12}:Ce (YAG). A similar result may be achieved by combining a UV emitting diode and at least three different UV absorbing phosphors: red, green, and blue emitting. These emitted colors mix to make white light. The efficiency of these LEDs is based on the combined efficiency of the LED, phosphor, and the interaction between the two. The Cabot SSL project attempted to improve the over all efficiency of the LED light source be improving the efficiency of the phosphor and the interaction between the LED light and the phosphor. Cabot's spray based process for producing phosphor powders is able to improve the brightness of the powder itself by increasing the activator (the species that emits the light) concentration without adverse quenching effects compared to conventional synthesis. This will allow less phosphor powder to be used, and will decrease the cost of the light source; thus lowering the barrier of entry to the lighting market. Cabot's process also allows for chemical flexibility of the phosphor particles, which may result in tunable emission spectra and so light sources with improved color rendering. Another benefit of Cabot's process is the resulting spherical morphology of the particles. Less light scattering results when spherical particles are used in the phosphor layer (Figure 1) compared to when conventional, irregular shaped phosphor particles are used. This spherical morphology will result in better light extraction and so an improvement of efficiency in the overall device. Cabot is a 2.5 billion dollar company that makes specialized materials using propriety spray based technologies. It is a core competency of Cabot's to exploit the spray based technology and resulting material/morphology advantages. Once a business opportunity is clearly identified, Cabot is positioned to increase the scale of the production to meet opportunity's need. Cabot has demonstrated the capability to make spherical morphology micron-sized phosphor powders by spray based routes for PDP and CRT applications, but the value proposition is still unproven for LED applications. Cabot believes that the improvements in phosphor powders yielded by their process will result in a commercial advantage over existing technologies. Through the SSL project, Cabot has produced a number of different compositions in a spherical morphology that may be useful for solid state lights, as well as demonstrated processes that are able to produce particles from 10 nanometers to 3 micrometers. Towards the end of the project we demonstrated that our process produces YAG:Ce powder that has both higher internal quantum efficiency (0.6 compared to 0.45) and external quantum efficiency (0.85 compared to 0.6) than the commercial standard (see section 3.4.4.3). We, however, only produced these highly bright materials in research and development quantities, and were never able to produce high quantum efficiency materials in a reproducible manner at a commercial scale.

  2. 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.

  3. 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

  4. LED R&D | Department of Energy

    Office of Environmental Management (EM)

    LED R&D LED R&D DOE-funded LED R&D projects tackle the science and technology challenges that stand in the way of achieving SSL Program targets for LED efficacy, performance, and cost. All project selections align with the priorities and targets detailed in the SSL R&D Plan, updated annually with industry input. Learn more about R&D challenges to accelerate LED technology advances. View details about the current LED R&D projects below. Novel Transparent Phosphor

  5. File:(131112) Presentacion LAC LEDs.pdf | Open Energy Information

    Open Energy Info (EERE)

    (131112) Presentacion LAC LEDs.pdf Jump to: navigation, search File File history File usage File:(131112) Presentacion LAC LEDs.pdf Size of this preview: 800 600 pixels. Go to...

  6. 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...

  7. DOE Publishes GATEWAY Report on Portland's LED Streetlight Conversion...

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

    Portland's LED Streetlight Conversion DOE Publishes GATEWAY Report on Portland's LED Streetlight Conversion October 5, 2015 - 11:08am Addthis The U.S. Department of Energy has ...

  8. Low-Cost LED Luminaire for General Illumination

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

    paulfini@cree.com CREE SBTC Low-Cost LED Luminaire for General Illumination 2014 Building ... end date: 73114 Key Milestones 1. White LED with custom primary optic providing 95% ...

  9. 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 ...

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

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

    gap," a portion of the spectrum where LED efficiency plunges, simulations at the U.S. ... Instead, most white lighting today comes from blue LED light passed through a phosphor, a ...

  11. CALiPER Application Summary Report 19. LED Linear Pendants

    SciTech Connect (OSTI)

    none,

    2012-10-01

    Report 19 reviews the independently tested performance of nine LED linear pendants and also evaluates a collection of 11 linear pendant products available in both an LED and fluorescent version.

  12. Team Led by Argonne National Lab Selected as DOE's Batteries...

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

    Team Led by Argonne National Lab Selected as DOE's Batteries and Energy Storage Hub On ... to announce that a multi-partner team led by Argonne National Laboratory has been ...

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

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

    Solar LED Light Pilot Project Illuminates the Way in Alabama EECBG Success Story: Solar LED Light Pilot Project Illuminates the Way in Alabama September 12, 2012 - 2:15pm Addthis ...

  14. 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 ...

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

    Office of Scientific and Technical Information (OSTI)

    GATEWAY program report on color shift data of LED lamps used in real-world applications as well as LED products monitored by the CALiPER program in a lab environment. Authors: ...

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

    Broader source: Energy.gov [DOE]

    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.

  17. LED Traffic Lights Get Buy American Stamp | Department of Energy

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

    over the past two years. Red. Yellow. Green. What LED traffic signals don't say: Made in USA. That is changing. Dialight Corporation, an LED lighting manufacturer with U.S....

  18. LED Luminaire Lifetime: Recommendations for Testing and Reporting

    Energy Savers [EERE]

    LED LUMINAIRE LIFETIME: RECOMMENDATIONS FOR TESTING AND REPORTING SOLID-STATE LIGHTING PRODUCT QUALITY INITIATIVE THIRD EDITION SEPTEMBER 2014 Next Generation Lighting Industry Alliance LED Systems Reliability Consortium i TABLE OF CONTENTS Acknowledgements.................................................................................................................................................................................... ii 1 Introduction and summary

  19. 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...

  20. Scalable Light Module for Low-Cost, High-Efficiency Light- Emitting Diode Luminaires

    SciTech Connect (OSTI)

    Tarsa, Eric

    2015-08-31

    During this two-year program Cree developed a scalable, modular optical architecture for low-cost, high-efficacy light emitting diode (LED) luminaires. Stated simply, the goal of this architecture was to efficiently and cost-effectively convey light from LEDs (point sources) to broad luminaire surfaces (area sources). By simultaneously developing warm-white LED components and low-cost, scalable optical elements, a high system optical efficiency resulted. To meet program goals, Cree evaluated novel approaches to improve LED component efficacy at high color quality while not sacrificing LED optical efficiency relative to conventional packages. Meanwhile, efficiently coupling light from LEDs into modular optical elements, followed by optimally distributing and extracting this light, were challenges that were addressed via novel optical design coupled with frequent experimental evaluations. Minimizing luminaire bill of materials and assembly costs were two guiding principles for all design work, in the effort to achieve luminaires with significantly lower normalized cost ($/klm) than existing LED fixtures. Chief project accomplishments included the achievement of >150 lm/W warm-white LEDs having primary optics compatible with low-cost modular optical elements. In addition, a prototype Light Module optical efficiency of over 90% was measured, demonstrating the potential of this scalable architecture for ultra-high-efficacy LED luminaires. Since the project ended, Cree has continued to evaluate optical element fabrication and assembly methods in an effort to rapidly transfer this scalable, cost-effective technology to Cree production development groups. The Light Module concept is likely to make a strong contribution to the development of new cost-effective, high-efficacy luminaries, thereby accelerating widespread adoption of energy-saving SSL in the U.S.

  1. List of LED Exit Signs Incentives | Open Energy Information

    Open Energy Info (EERE)

    upgrades Water Heaters Whole House Fans LED Exit Signs CHPCogeneration Biomass Photovoltaics Yes Energy Optimization (Electric) - Commercial Efficiency Program...

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

    Office of Energy Efficiency and Renewable Energy (EERE)

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

  3. High Efficiency Driving Electronics for General Illumination LED Luminaires

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

    (Technical Report) | SciTech Connect High Efficiency Driving Electronics for General Illumination LED Luminaires Citation Details In-Document Search Title: High Efficiency Driving Electronics for General Illumination LED Luminaires New generation of standalone LED driver platforms developed, which are more efficient These LED Drivers are more efficient (≥90%), smaller in size ( 0.15 in3/watt), lower in cost ( 12 cents/watt in high volumes in millions of units). And these products are very

  4. High Efficiency Driving Electronics for General Illumination LED Luminaires

    Office of Scientific and Technical Information (OSTI)

    (Technical Report) | SciTech Connect SciTech Connect Search Results Technical Report: High Efficiency Driving Electronics for General Illumination LED Luminaires Citation Details In-Document Search Title: High Efficiency Driving Electronics for General Illumination LED Luminaires New generation of standalone LED driver platforms developed, which are more efficient These LED Drivers are more efficient (≥90%), smaller in size ( 0.15 in3/watt), lower in cost ( 12 cents/watt in high volumes in

  5. 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.

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

    Broader source: Energy.gov [DOE]

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

  7. 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.

  8. Simple Modular LED Cost Model | Department of Energy

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

    Tools » Simple Modular LED Cost Model Simple Modular LED Cost Model The LED Cost Model, developed by the DOE Cost Modeling Working Group, provides a simplified method for analyzing the manufacturing costs of an LED package. The model focuses on the major cost elements and includes preliminary raw data and manufacturing process flow, which provide a starting point and can be customized by the user to model different processes, materials, and equipment. The tool enables those involved in the

  9. DOE Publishes Technical Brief Clarifying Misconceptions about Safety of LED

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

    Lighting | Department of Energy Technical Brief Clarifying Misconceptions about Safety of LED Lighting DOE Publishes Technical Brief Clarifying Misconceptions about Safety of LED Lighting October 22, 2014 - 12:00pm Addthis The spectral emission of LEDs is a frequent subject of concern, so to set the record straight, the U.S. Department of Energy has published a technical brief entitled True Colors: LEDs and the Relationship Between CCT, CRI, Optical Safety, Material Degradation, and

  10. UNDERSTANDING LED COLOR-TUNABLE PRODUCTS | Department of Energy

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

    UNDERSTANDING LED COLOR-TUNABLE PRODUCTS UNDERSTANDING LED COLOR-TUNABLE PRODUCTS 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 capabilities have brought them greater acclaim and expanded the range of potential applications. There are three basic categories of color-tunable products: Dim-to-warm These products, also referred to as warm dim, blackbody

  11. High Impact Technology HQ - Results - LED Troffer, Cove (linear) and

    Energy Savers [EERE]

    Downlight Retrofit Kits: Princeton Icahn Laboratory | Department of Energy HQ - Results - LED Troffer, Cove (linear) and Downlight Retrofit Kits: Princeton Icahn Laboratory High Impact Technology HQ - Results - LED Troffer, Cove (linear) and Downlight Retrofit Kits: Princeton Icahn Laboratory PDF icon LED Troffer, Cove (linear) and Downlight Retrofit Kits: Princeton Icahn Laboratory More Documents & Publications DOE Booth Presentations From Grainger Show 2015 Downloads Exterior LED

  12. Study: Environmental Benefits of LEDs Greater Than CFLs | Department of

    Energy Savers [EERE]

    Energy Study: Environmental Benefits of LEDs Greater Than CFLs Study: Environmental Benefits of LEDs Greater Than CFLs December 9, 2013 - 4:13pm Addthis A three-part Energy Department-funded study indicates LEDs are more environmentally friendly than compact fluorescent and incandescent lights. | Energy Department graphic A three-part Energy Department-funded study indicates LEDs are more environmentally friendly than compact fluorescent and incandescent lights. | Energy Department graphic

  13. REA Refrigerated Display Case LED Lighting Performance Specification |

    Energy Savers [EERE]

    Department of Energy REA Refrigerated Display Case LED Lighting Performance Specification REA Refrigerated Display Case LED Lighting Performance Specification A Retailer Energy Alliances (REA) Project PDF icon rea_refrig_display_spec.pdf More Documents & Publications CBEA LED Site Lighting Specification - Version 1.3, Released 2/15/2012 Model Specification for LED Roadway Luminaires, V2.0 CBEA High-Efficiency Parking Structure Lighting Specification

  14. Financing Guidance for LED Street Lighting Programs | Department of Energy

    Office of Environmental Management (EM)

    Financing Guidance for LED Street Lighting Programs Financing Guidance for LED Street Lighting Programs photo of an urban roadway at night lined with LED streetlights. Financing an LED street lighting replacement program can present a hurdle for many system owners, even if the planned transition offers very favorable economics. Replacing the existing system requires a significant budget, particularly as the scope of the program increases. Cities such as Los Angeles and Seattle have invested many

  15. Maintenance Practices for LED Streetlights | Department of Energy

    Office of Environmental Management (EM)

    Information Resources » Webcasts » Maintenance Practices for LED Streetlights Maintenance Practices for LED Streetlights 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 transition to LED street lighting. Presenters Glenn Cooper of the City of Boston, Stephen Crume of the City of Seattle, and Patrick Batte of the City of Las Vegas discussed actual field

  16. Considerations When Comparing LED and Conventional Lighting | Department of

    Office of Environmental Management (EM)

    Energy Using LEDs » Considerations When Comparing LED and Conventional Lighting Considerations When Comparing LED and Conventional Lighting When comparing LED lighting performance to conventional lighting, buyers will want to consider energy efficiency, operating life and lumen depreciation, light output/distribution, color quality, color shift, dimmability, and expected lifetime. Energy efficiency The final energy efficiency of any lighting system depends on more than the efficacy of the

  17. Fact #663: February 21, 2011 Clean Cities Program Petroleum Displacement

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

    Estimates for 2009 | Department of Energy 3: February 21, 2011 Clean Cities Program Petroleum Displacement Estimates for 2009 Fact #663: February 21, 2011 Clean Cities Program Petroleum Displacement Estimates for 2009 Each year, estimates are made of the amount of petroleum that is displaced by the efforts of the U.S. Department of Energy's Clean Cities Program. These estimates are based on data provided by Clean Cities Coalition coordinators around the country and serve as an indicator of

  18. 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.

  19. 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.

  20. Philadelphia International Airport Apron Lighting: LED System Performance

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

    in a Trial Installation | Department of Energy Philadelphia International Airport Apron Lighting: LED System Performance in a Trial Installation Philadelphia International Airport Apron Lighting: LED System Performance in a Trial Installation PDF icon 2015_gateway_philadelphia-airport.pdf PDF icon gateway_philadelphia-airport_brief.pdf More Documents & Publications LED Performance Under Tough Conditions December 2015 Postings 2015 ARTICLES

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

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

    Department of Energy Princeton University and DOE GATEWAY Demonstrations LEDs Go Ivy League: Princeton University and DOE GATEWAY Demonstrations 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 uses, benefits, and progress of LED lighting at Princeton

  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. Report 23: Photometric Testing of White Tunable LED Luminaires | Department

    Energy Savers [EERE]

    of Energy 3: Photometric Testing of White Tunable LED Luminaires Report 23: Photometric Testing of White Tunable LED Luminaires PDF icon caliper_23_white-tunable-led-luminaires.pdf More Documents & Publications September 2015 Postings January 2016 POSTINGS 2015 SSL TECHNOLOGY DEVELOPMENT WORKSHOP PRESENTATIONS - Day 2

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

    Energy Savers [EERE]

    Department of Energy Princeton University and DOE GATEWAY Demonstrations LEDs Go Ivy League: Princeton University and DOE GATEWAY Demonstrations 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 uses, benefits, and progress of LED lighting at Princeton

  6. 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.

  7. Phase-field Modeling of Displacive Phase Transformations in Elasticall...

    Office of Scientific and Technical Information (OSTI)

    Phase-field Modeling of Displacive Phase Transformations in Elastically Anisotropic and Inhomogeneous Polycrystals Citation Details In-Document Search Title: Phase-field Modeling...

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. Demonstration Assessment of Light-Emitting Diode Parking Structure Lighting at U.S. Department of Labor Headquarters

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Myer, Michael

    2013-03-01

    This report documents a solid-state lighting (SSL) technology demonstration at the parking structure of the U.S. Department of Labor (DOL) Headquarters in Washington, DC, in which light-emitting diode (LED) luminaires were substituted for the incumbent high-pressure sodium (HPS) luminaires and evaluated for relative light quantity and performance. The demonstration results show energy savings of 52% from the initial conversion of HPS to the LED product. These savings were increased to 88% by using occupancy sensor controls that were ultimately set to reduce power to 10% of high state operation after a time delay of 2.5 minutes. Because of the relatively high cost of the LED luminaires at their time of purchase for this project (2010), the simple payback periods were 6.5 years and 4.9 years for retrofit and new construction scenarios, respectively. Staff at DOL Headquarters reported high satisfaction with the operation of the LED product.

  13. 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.

  14. 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.

  15. Color tuning of light-emitting-diodes by modulating the concentration of red-emitting silicon nanocrystal phosphors

    SciTech Connect (OSTI)

    Barillaro, G. Strambini, L. M.

    2014-03-03

    Luminescent forms of nanostructured silicon have received significant attention in the context of quantum-confined light-emitting devices thanks to size-tunable emission wavelength and high-intensity photoluminescence, as well as natural abundance, low cost, and non-toxicity. Here, we show that red-emitting silicon nanocrystal (SiN) phosphors, obtained by electrochemical erosion of silicon, allow for effectively tuning the color of commercial light-emitting-diodes (LEDs) from blue to violet, magenta, and red, by coating the LED with polydimethylsiloxane encapsulating different SiN concentrations. High reliability of the tuning process, with respect to SiN fabrication and concentration, and excellent stability of the tuning color, with respect to LED bias current, is demonstrated through simultaneous electrical/optical characterization of SiN-modified commercial LEDs, thus envisaging exciting perspectives for silicon nanocrystals in the field of light-emitting applications.

  16. 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.

  17. LED Performance Specification Series: T8 Replacement Lamps

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

    Photo credit: PNNL LED T8 replacements may contain dozens of high power LEDs or hundreds of 5mm LEDs behind a clear or frosted lens, all in a medium bi-pin T8 lamp package. Table 1. CALiPER Test Results for 4-foot LED T8 Replacements with Fluorescent Benchmarks Performance Characteristics LED T8 Replacements Fluorescent Benchmarks Range (12 lamps tested) Average Mfr. Data (75 lamps) CALiPER (2 fxtures tested) Initial Lamp Light Output (lm) 345 - 1,579 1,111 2,778 3,091 Initial 2-Lamp System

  18. LED Linear Lamps and Troffer Lighting | Department of Energy

    Energy Savers [EERE]

    Linear Lamps and Troffer Lighting LED Linear Lamps and Troffer Lighting View the video about CALiPER Series 21 on LED Linear Lamps and Troffer Lighting. 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

  19. 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.

  20. Uniform insulation applied-B ion diode

    DOE Patents [OSTI]

    Seidel, David B. (Albuquerque, NM); Slutz, Stephen A. (Albuquerque, NM)

    1988-01-01

    An applied-B field extraction ion diode has uniform insulation over an anode surface for increased efficiency. When the uniform insulation is accomplished with anode coils, and a charge-exchange foil is properly placed, the ions may be focused at a point on the z axis.

  1. 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.

  2. 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.

  3. Modified Newmark model for seismic displacements of compliant slopes

    SciTech Connect (OSTI)

    Kramer, S.L.; Smith, M.W.

    1997-07-01

    Newmark sliding block analyses are widely used for estimation of permanent displacements of slopes in earthquakes. The conventional Newmark model, however, neglects the dynamic response of the material above a potential failure surface. Decoupled procedures have been developed to account for that response, but they neglect the effects of permanent displacements on the response. A modified Newmark analysis that considers the dynamic response, including the effects of permanent displacements, of the material above the failure surface is presented. The modified Newmark analysis shows that the decoupled approach produces somewhat conservative estimates of permanent displacements for stiff and/or shallow failure masses, but that it may produce unconservative estimates for failure masses that are soft and/or deep. Many slopes of large, lined landfills may fall into this latter category. The notion of a slope spectrum, which illustrates the effect of the natural period of a potential failure mass on permanent slope displacement, is also introduced.

  4. Effect of heterostructure design on carrier injection and emission characteristics of 295?nm light emitting diodes

    SciTech Connect (OSTI)

    Mehnke, Frank Kuhn, Christian; Stellmach, Joachim; Rothe, Mark-Antonius; Reich, Christoph; Ledentsov, Nikolay; Pristovsek, Markus; Wernicke, Tim; Kolbe, Tim; Lobo-Ploch, Neysha; Rass, Jens; Kneissl, Michael

    2015-05-21

    The effects of the heterostructure design on the injection efficiency and external quantum efficiency of ultraviolet (UV)-B light emitting diodes (LEDs) have been investigated. It was found that the functionality of the Al{sub x}Ga{sub 1?x}N:Mg electron blocking layer is strongly influenced by its aluminum mole fraction x and its magnesium doping profile. By comparing LED electroluminescence, quantum well photoluminescence, and simulations of LED heterostructure, we were able to differentiate the contributions of injection efficiency and internal quantum efficiency to the external quantum efficiency of UV LEDs. For the optimized heterostructure using an Al{sub 0.7}Ga{sub 0.3}N:Mg electron blocking layer with a Mg to group III ratio of 4% in the gas phase the electron leakage currents are suppressed without blocking the injection of holes into the multiple quantum well active region. Flip chip mounted LED chips have been processed achieving a maximum output power of 3.5 mW at 290?mA and a peak external quantum efficiency of 0.54% at 30?mA.

  5. 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 lclairage 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.

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

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

    HVAC Units: February 11, 2010 | Department of Energy (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 Units: February 11, 2010 PDF icon nationwide_nonavailability_waiver_02-11-2010 More Documents & Publications Nationwide Categorical Waiver Nationwide Nonavailability Waiver: February 11, 2010 (Please note, the waiver for LED traffic signals has been

  7. Demonstration Assessment of LED Roadway Lighting: Philadelphia, PA

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

    (Technical Report) | SciTech Connect Demonstration Assessment of LED Roadway Lighting: Philadelphia, PA Citation Details In-Document Search Title: Demonstration Assessment of LED Roadway Lighting: Philadelphia, PA For this demonstration assessment, 10 different groups of LED luminaires were installed at three sites in Philadelphia, PA. Each of the three sites represented a different set of conditions, most importantly with regard to the incumbent HPS luminaires, which were nominally 100 W,

  8. Color Maintenance of LEDs in Laboratory and Field Applications (Technical

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

    Report) | SciTech Connect Color Maintenance of LEDs in Laboratory and Field Applications Citation Details In-Document Search Title: Color Maintenance of LEDs in Laboratory and Field Applications Synopsis: To date, consideration for parametric failure of LED products has largely been focused on lumen maintenance. However, color shift is a cause of early failure for some products, and is especially important to consider in certain applications, like museums, where visual appearance is

  9. Energy Department Announces New Investments in University-Led Nuclear

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

    Energy Innovation | Department of Energy in University-Led Nuclear Energy Innovation Energy Department Announces New Investments in University-Led Nuclear Energy Innovation September 27, 2012 - 11:07am Addthis WASHINGTON - As part of the Obama Administration's all-of-the-above energy strategy to deploy every available source of American energy and ensure the U.S. remains competitive globally, the Energy Department announced today more than $13 million in new investments for university-led

  10. Considering LEDs for Street and Area Lighting | Department of Energy

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

    Information Resources » Videos » Considering LEDs for Street and Area Lighting Considering LEDs for Street and Area Lighting View Jim Brodrick's keynote video from the September 2009 IES Street and Area Lighting Conference in Philadelphia. View the text-alternative version. Solid-State Lighting Home About the Solid-State Lighting Program Research & Development SSL Basics Using LEDs Information Resources Conferences & Meetings Presentations Publications Webcasts Videos Tools

  11. DOE Publishes GATEWAY Report on Successful LED Wall Washer Retrofit |

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

    Department of Energy Successful LED Wall Washer Retrofit DOE Publishes GATEWAY Report on Successful LED Wall Washer Retrofit August 5, 2015 - 1:00pm Addthis The U.S. Department of Energy has released a report on a GATEWAY demonstration, in which maintenance and energy costs were significantly reduced while retaining the quality of light when LED modules replaced 87 halogen lamps in existing wall washers at the University of Maryland's (UMD) Clarice Smith Performing Arts Center. The project

  12. Model Specification for LED Roadway Luminaires Webcast | Department of

    Energy Savers [EERE]

    Energy Webcasts » Model Specification for LED Roadway Luminaires Webcast Model Specification for LED Roadway Luminaires Webcast This November 15, 2011 webcast presented information about the Model Specification for LED Roadway Luminaires developed by DOE's Municipal Solid-State Street Lighting Consortium. During the webcast, Jason Tuenge of Pacific Northwest National Laboratory provided an overview of the model specification and explained how it can be customized to meet the particular

  13. Municipal Consortium Releases Updated Model Specification for LED Roadway

    Energy Savers [EERE]

    Luminaires | Department of Energy for LED Roadway Luminaires Municipal Consortium Releases Updated Model Specification for LED Roadway Luminaires July 10, 2014 - 10:23am Addthis The U.S. Department of Energy's Municipal Solid-State Street Lighting Consortium (MSSLC) has released the first updated version of its Model Specification for LED Roadway Luminaires. A "living document" that's updated as needed to reflect changes in technologies and associated standards, and to incorporate

  14. Dimming LEDs: What You Need to Know | Department of Energy

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

    Information Resources » Webcasts » Dimming LEDs: What You Need to Know Dimming LEDs: What You Need to Know This December 10, 2012 webcast presented information on the challenges and opportunities facing users trying to dim LED light sources today, reviewing the major types of deployed dimming technologies and equipment and some of the factors that lead to performance problems and incompatibilities. Michael Poplawski of Pacific Northwest National Laboratory walked through examples of what can

  15. Secretary Moniz Applauds Detroit's LED Street Lighting Upgrades |

    Energy Savers [EERE]

    Department of Energy Secretary Moniz Applauds Detroit's LED Street Lighting Upgrades Secretary Moniz Applauds Detroit's LED Street Lighting Upgrades June 16, 2014 - 10:46am Addthis Secretary of Energy Ernest Moniz visited Detroit on May 22, 2014, to mark the city's progress installing energy-efficient LED streetlights in an update of its largely broken public lighting system, speaking at the Detroit Area Pre-College Engineering Program. Like so many cities across the country, Detroit is

  16. Successful Selection of LED Streetlight Luminaires: Optimizing Illumination

    Energy Savers [EERE]

    and Economic Performance | Department of Energy Successful Selection of LED Streetlight Luminaires: Optimizing Illumination and Economic Performance Successful Selection of LED Streetlight Luminaires: Optimizing Illumination and Economic Performance This March 6, 2013 webcast reviewed the factors involved in successful selection of LED streetlight luminaires. Presenters Eric Haugaard of Cree Lighting and Chad Stalker of Philips Lumileds guided participants through the modeling of a typical

  17. Reducing LED Costs Through Innovation | Department of Energy

    Energy Savers [EERE]

    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 cuts a thin steel plate that will be formed into lighting fixture housing. Wisconsin-based Eaton Corporation is developing a new manufacturing process that streamlines LED fixture designs. | Photo courtesy of Eaton Corporation A combination solid-state laser turret cutter and stamping machine cuts a thin steel plate that will be

  18. LED LUMINAIRE LIFETIME: Recommendations for Testing and Reporting |

    Energy Savers [EERE]

    Department of Energy LUMINAIRE LIFETIME: Recommendations for Testing and Reporting LED LUMINAIRE LIFETIME: Recommendations for Testing and Reporting 2011 Solid-State Lighting Product Quality Initiative PDF icon led_luminaire-lifetime-guide_june2011.pdf More Documents & Publications System Reliability Model for Solid-State Lighting Luminaires LED Luminaire Lifetime: Recommendations For Testing and Reporting System Reliability Model for Solid-State Lighting Luminaires

  19. LED Replacements for Linear Fluorescent Lamps Webcast | Department of

    Energy Savers [EERE]

    Energy Replacements for Linear Fluorescent Lamps Webcast LED Replacements for Linear Fluorescent Lamps Webcast 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 Facts-listed products as well as products evaluated in the latest CALiPER reports. Eric Richman, also of PNNL, reported on a recently completed GATEWAY demonstration project, in which LED and

  20. LED Street Lighting Conversion Workshop Presentations | Department of

    Energy Savers [EERE]

    Energy Research & Development » Technology Application R&D » Municipal Consortium » News & Events » LED Street Lighting Conversion Workshop Presentations LED Street Lighting Conversion Workshop Presentations 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, held November 13, 2013, in Seattle, WA. Presentations and Materials State of

  1. LEDs Go Ivy League: Princeton's Dillon Gymnasium | Department of Energy

    Energy Savers [EERE]

    Princeton's Dillon Gymnasium LEDs Go Ivy League: Princeton's Dillon Gymnasium 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 describes the challenges of the installation, which included the need for a custom interface so the lighting controls would operate within in the Lutron Ecosystem

  2. LEDs for Interior Office Applications Webcast | Department of Energy

    Energy Savers [EERE]

    LEDs for Interior Office Applications Webcast LEDs for Interior Office Applications Webcast In this March 18, 2010 webcast, Jason Tuenge and Michael Myer of Pacific Northwest National Laboratory described the performance and economic considerations of replacing either 4' T8 lamps or entire troffer-type luminaires with LED products. The webcast also compared manufacturer performance claims about these types of products against test results from DOE's CALiPER program. View presentation slides (PDF

  3. TESTING LED COLOR-TUNABLE PRODUCTS | Department of Energy

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

    TESTING LED COLOR-TUNABLE PRODUCTS TESTING LED COLOR-TUNABLE PRODUCTS Cover of CALiPER Report 23. New product capabilities and performance variables require new test methods to be developed, which is important for industry because accurate, repeatable, standardized test methods enable accurate comparisons. Measuring and reporting performance of LED color-tunable luminaires poses a new challenge, since the range of possibilities is near limitless. With variable spectral power distribution (i.e.,

  4. NETL-Led Laboratory-Industry-Academia Collaboration Is Accelerating

    Office of Environmental Management (EM)

    Carbon-Capture Technologies | Department of Energy NETL-Led Laboratory-Industry-Academia Collaboration Is Accelerating Carbon-Capture Technologies NETL-Led Laboratory-Industry-Academia Collaboration Is Accelerating Carbon-Capture Technologies April 2, 2014 - 9:31am Addthis NETL-Led Laboratory-Industry-Academia Collaboration Is Accelerating Carbon-Capture Technologies Check out NETL's latest video on CCSI. In 2011, the Office of Fossil Energy's National Energy Technology Laboratory (NETL)

  5. LEDS Collaboration in Action Workshop Biography | Open Energy...

    Open Energy Info (EERE)

    LEDS Collaboration in Action Workshop Biography Jump to: navigation, search Low Emission Development Strategies Global Partnership Advancing climate-resilient, low-emission...

  6. LEDS Collaboration in Action Workshop Open Space Sessions | Open...

    Open Energy Info (EERE)

    LEDS Collaboration in Action Workshop Open Space Sessions Jump to: navigation, search Low Emission Development Strategies Global Partnership Advancing climate-resilient,...

  7. LEDS Collaboration in Action Workshop Links | Open Energy Information

    Open Energy Info (EERE)

    LEDS Collaboration in Action Workshop Links Jump to: navigation, search Low Emission Development Strategies Global Partnership Advancing climate-resilient, low-emission development...

  8. LEDS Collaboration in Action Workshop Accommodations | Open Energy...

    Open Energy Info (EERE)

    LEDS Collaboration in Action Workshop Accommodations Jump to: navigation, search Low Emission Development Strategies Global Partnership Advancing climate-resilient, low-emission...

  9. LEDS Collaboration in Action Workshop Agenda | Open Energy Information

    Open Energy Info (EERE)

    LEDS Collaboration in Action Workshop Agenda Jump to: navigation, search Low Emission Development Strategies Global Partnership Advancing climate-resilient, low-emission...

  10. LEDS Collaboration in Action Workshop Participant Pack | Open...

    Open Energy Info (EERE)

    LEDS Collaboration in Action Workshop Participant Pack Jump to: navigation, search Low Emission Development Strategies Global Partnership Advancing climate-resilient, low-emission...

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

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: LED, ssl, solid-state, lighting, GATEWAY, CALiPER, report, color, shift, maintenance Word Cloud More Like This Full ...

  12. LED Site Lighting in the Commercial Building Sector: Opportunities...

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

    Site Lighting in the Commercial Building Sector: Opportunities, Challenges, and the CBEA Performance Specification LED Site Lighting in the Commercial Building Sector: ...

  13. Nationwide Limited Public Interest Waiver for LED and HVAC Units...

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

    Nationwide Nonavailability Waiver: February 11, 2010 (Please note, the waiver for LED traffic signals has been withdrawn effective December 1, 2010) Nationwide...

  14. IADB/UNDP LEDS Community of Practice | Open Energy Information

    Open Energy Info (EERE)

    to communicate different methods for preparation of LED strategies including: The involvement of sectors and stakeholders Updating GHG inventories Preparation and analysis of...

  15. Secretary Chu Announces Funding for 71 University-Led Nuclear...

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

    Secretary Chu Announces Funding for 71 University-Led Nuclear Research and Development Projects WASHINGTON, DC U.S. Energy Secretary Steven Chu today announced the selection of ...

  16. LED Lighting Facts/CALiPER Snapshot. Outdoor Ambient Lighting

    SciTech Connect (OSTI)

    2013-07-01

    Snapshot reports reveal how today's products really perform, drawing on analysis of verified performance data from the LED Lighting Facts program's online product list.

  17. LEDS Collaboration in Action Workshop Contact Us | Open Energy...

    Open Energy Info (EERE)

    LEDS Collaboration in Action Workshop Contact Us Jump to: navigation, search Low Emission Development Strategies Global Partnership Advancing climate-resilient, low-emission...

  18. High Bandgap Phosphide Approaches for LED Applications - Energy...

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

    A new approach to fabricating high-efficiency Amber LEDs National Renewable Energy Laboratory Contact NREL About This Technology Publications: PDF Document Publication AlInP Green ...

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

    Broader source: Energy.gov [DOE]

    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.

  20. Study: Environmental Benefits of LEDs Greater Than CFLs | Department...

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

    to date. The study - which evaluated not only the use but also the manufacturing, transport, and disposal of LED, CFL, and incandescent lamps throughout each product...

  1. LED Lights for All Occasions | Department of Energy

    Office of Environmental Management (EM)

    Lights for All Occasions LED Lights for All Occasions November 15, 2012 - 1:15pm Addthis With such a variety of lights available, LEDs are a perfect choice for holiday lighting. | Photo courtesy of ©iStockphoto.com/Birzio With such a variety of lights available, LEDs are a perfect choice for holiday lighting. | Photo courtesy of ©iStockphoto.com/Birzio Elizabeth Spencer Communicator, National Renewable Energy Laboratory What does this mean for me? Energy-efficient LED lights can be used to

  2. 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.

  3. Have You Used LED Light Strings? | Department of Energy

    Office of Environmental Management (EM)

    Used LED Light Strings? Have You Used LED Light Strings? December 3, 2009 - 7:30am Addthis This week, you read about LED holiday light strings, which can use 90% less energy than regular incandescent light strings. You may even be able to save on the initial costs with rebates from stores or your utility; check to find out what's being offered in your area. Have you used LED light strings? Tell us what you think of them. Each Thursday, you have the chance to share your thoughts on a question

  4. #AskEnergySaver: LED Lights | Department of Energy

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

    LED Lights #AskEnergySaver: LED Lights April 24, 2014 - 6:00pm Addthis LED lights are six to seven times more energy efficient than conventional incandescent lights, cut energy use by more than 80 percent and can last more than 25 times longer. | Photo courtesy of Dennis Schroeder, NREL. LED lights are six to seven times more energy efficient than conventional incandescent lights, cut energy use by more than 80 percent and can last more than 25 times longer. | Photo courtesy of Dennis Schroeder,

  5. Floor-supply displacement air-conditioning: Laboratory experiments

    SciTech Connect (OSTI)

    Akimoto, Takashi; Nobe, Tatsuo; Tanabe, Shinichi; Kimura, Kenichi

    1999-07-01

    The results of laboratory measurements on the performance of a floor-supply displacement air-conditioning system in comparison to a displacement ventilation system with a side-wall-mounted diffuser and a ceiling-based distribution system are described. Thermal stratification was observed, as there were greater vertical air temperature differences in both of the displacement systems than in the ceiling-based system. The floor-supply displacement air-conditioning system produced a uniformly low air velocity at each measurement height, while a rather high air velocity near the floor was observed for the displacement ventilation system with a sidewall-mounted diffuser. Local mean age of air of the floor-supply displacement air-conditioning system was lower than that of the other systems, especially in the lower part of the room. According to the simulation results, the floor-supply displacement air-conditioning system with outdoor air cooling requires 34% less energy than the conventional air-conditioning system with outdoor air cooling.

  6. Characterization of electrically-active defects in ultraviolet light-emitting diodes with laser-based failure analysis techniques

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

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

    2016-01-12

    In this study, laser-based failure analysis techniques demonstrate the ability to quickly and non-intrusively screen deep ultraviolet light-emitting diodes(LEDs) for electrically-active defects. In particular, two laser-based techniques, light-induced voltage alteration and thermally-induced voltage alteration, generate applied voltage maps (AVMs) that provide information on electrically-active defect behavior including turn-on bias, density, and spatial location. Here, multiple commercial LEDs were examined and found to have dark defect signals in the AVM indicating a site of reduced resistance or leakage through the diode. The existence of the dark defect signals in the AVM correlates strongly with an increased forward-bias leakage current. This increasedmore » leakage is not present in devices without AVM signals. Transmission electron microscopyanalysis of a dark defect signal site revealed a dislocation cluster through the pn junction. The cluster included an open core dislocation. Even though LEDs with few dark AVM defect signals did not correlate strongly with power loss, direct association between increased open core dislocation densities and reduced LED device performance has been presented elsewhere [M. W. Moseley et al., J. Appl. Phys. 117, 095301 (2015)].« less

  7. Performance and breakdown characteristics of irradiated vertical power GaN P-i-N diodes

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

    King, M. P.; Armstrong, A. M.; Dickerson, J. R.; Vizkelethy, G.; Fleming, R. M.; Campbell, J.; Wampler, W. R.; Kizilyalli, I. C.; Bour, D. P.; Aktas, O.; et al

    2015-10-29

    Electrical performance and defect characterization of vertical GaN P-i-N diodes before and after irradiation with 2.5 MeV protons and neutrons is investigated. Devices exhibit increase in specific on-resistance following irradiation with protons and neutrons, indicating displacement damage introduces defects into the p-GaN and n- drift regions of the device that impact on-state device performance. The breakdown voltage of these devices, initially above 1700 V, is observed to decrease only slightly for particle fluence <; 1013 cm-2. Furthermore, the unipolar figure of merit for power devices indicates that while the on-resistance and breakdown voltage degrade with irradiation, vertical GaN P-i-Ns remainmore » superior to the performance of the best available, unirradiated silicon devices and on-par with unirradiated modern SiC-based power devices.« less

  8. Infrared photoemitting diode having reduced work function

    DOE Patents [OSTI]

    Hirschfeld, Tomas B. (Livermore, CA)

    1984-01-01

    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 medium 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.

  9. 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.

  10. DIODE STEERED MANGETIC-CORE MEMORY

    DOE Patents [OSTI]

    Melmed, A.S.; Shevlin, R.T.; Laupheimer, R.

    1962-09-18

    A word-arranged magnetic-core memory is designed for use in a digital computer utilizing the reverse or back current property of the semi-conductor diodes to restore the information in the memory after read-out. In order to ob tain a read-out signal from a magnetic core storage unit, it is necessary to change the states of some of the magnetic cores. In order to retain the information in the memory after read-out it is then necessary to provide a means to return the switched cores to their states before read-out. A rewrite driver passes a pulse back through each row of cores in which some switching has taken place. This pulse combines with the reverse current pulses of diodes for each column in which a core is switched during read-out to cause the particular cores to be switched back into their states prior to read-out. (AEC)

  11. Advancements in ion diode and triode design

    SciTech Connect (OSTI)

    Cavenago, M., E-mail: cavenago@lnl.infn.it [INFN-LNL, viale dell'Universit 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.

  12. 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.

  13. 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.

  14. 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:...

  15. Adsorption, Desorption, and Displacement Kinetics of H2O and...

    Office of Scientific and Technical Information (OSTI)

    4 H2O to 3 CO2 molecules is needed to displace CO2 from the TiO2(110) surface. Authors: Smith, R. Scott ; Li, Zhenjun ; Chen, Long ; Dohnalek, Zdenek ; Kay, Bruce D. Publication...

  16. Performance evaluation and design guidelines for displacement ventilation

    SciTech Connect (OSTI)

    Yuan, X.; Chen, Q.; Glicksman, L.R.

    1999-07-01

    This paper evaluates the performance of traditional displacement ventilation systems for small offices, large offices with partitions, classrooms, and industrial workshops under US thermal and flow boundary conditions, such as a high cooling load. With proper design, displacement ventilation can maintain a thermally comfortable environment that has a low air velocity, a small temperature difference between the head and foot level, and a low percentage of dissatisfied people. Compared with conventional mixing ventilation, displacement ventilation may provide better indoor air quality in the occupied zone when the contaminant sources are associated with the heat sources. The mean age of air is younger, and the ventilation effectiveness is higher. Based on results from Scandinavian countries and the authors' investigation of US buildings, this paper presents guidelines for designing displacement ventilation in the US.

  17. Phase-field Modeling of Displacive Phase Transformations in Elastically

    Office of Scientific and Technical Information (OSTI)

    Anisotropic and Inhomogeneous Polycrystals (Journal Article) | SciTech Connect Phase-field Modeling of Displacive Phase Transformations in Elastically Anisotropic and Inhomogeneous Polycrystals Citation Details In-Document Search Title: Phase-field Modeling of Displacive Phase Transformations in Elastically Anisotropic and Inhomogeneous Polycrystals Authors: Heo, T W ; Chen, L Q Publication Date: 2014-03-06 OSTI Identifier: 1169262 Report Number(s): LLNL-JRNL-651372 DOE Contract Number:

  18. Features of primary damage by high energy displacement cascades in

    Office of Scientific and Technical Information (OSTI)

    concentrated Ni-based alloys (Journal Article) | DOE PAGES Features of primary damage by high energy displacement cascades in concentrated Ni-based alloys This content will become publicly available on February 25, 2017 « Prev Next » Title: Features of primary damage by high energy displacement cascades in concentrated Ni-based alloys Alloying of Ni with Fe or Co reduces primary damage production under ion irradiation. Similar results have been obtained from classical molecular dynamics

  19. LANSCE | Lujan Center | Highlights | Local iron displacements and

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

    magnetoelastic coupling in a spin-ladder compound Local iron displacements and magnetoelastic coupling in a spin-ladder compound Hypothesis: Is magnetoelastic coupling in [FeX4]-based materials, an important ingredient in the emergence of superconductivity? Lujan Center: Combined Total Scattering and magnetic structure determination (HIPD-NPDF) The study of local, average and magnetic structure shows the existenceof highly correlated local iron (Fe) displacements in the spin-ladder iron

  20. Clean Cities 2009 Petroleum Displacement Awards | Department of Energy

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

    2009 Petroleum Displacement Awards Clean Cities 2009 Petroleum Displacement Awards 2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation PDF icon ti004_scarpino_2011_o.pdf More Documents & Publications Clean Cities Recovery Act: Vehicle & Infrastructure Deployment EV Community Readiness projects: South Florida Regional Planning Council; Virginia Department of Mines, Minerals and Energy EV Community Readiness projects: Center

  1. Clean Cities Regional Support & Petroleum Displacement Awards | Department

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

    of Energy Regional Support & Petroleum Displacement Awards Clean Cities Regional Support & Petroleum Displacement Awards 2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. PDF icon ti_09_scarpino.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2014: Alternative Fuels Implementation Team (AFIT) for North Carolina 2008 Annual Merit Review Results Summary - 15.

  2. National Labs Open Doors to Displaced Japanese Researchers | Department of

    Office of Environmental Management (EM)

    Energy Labs Open Doors to Displaced Japanese Researchers National Labs Open Doors to Displaced Japanese Researchers July 5, 2011 - 1:42pm Addthis Maiko Kofu, Atsushi Nagoe and Osamu Yamamuro examine their sample attached to the end of the cryostat stick after running an experiment at Oak Ridge National Laboratory’s Spallation Neutron Source. | Department of Energy Photo | Courtesy of Oak Ridge National Laboratory | Public Domain | Maiko Kofu, Atsushi Nagoe and Osamu Yamamuro examine

  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. Thermal Reliability Study of Bypass Diodes in Photovoltaic Modules |

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

    Department of Energy Thermal Reliability Study of Bypass Diodes in Photovoltaic Modules Thermal Reliability Study of Bypass Diodes in Photovoltaic Modules Presented at the PV Module Reliability Workshop, February 26 - 27 2013, Golden, Colorado PDF icon pvmrw13_ps3_nrel_zhang.pdf More Documents & Publications US TG 4 Activities of QA Forum US & Japan TG 4 Activities of QA Forum High Temperature Reverse By-Pass Diodes Bias and Failures

  5. 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.

  6. 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}.

  7. 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.

  8. 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.

  9. 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.

  10. High Temperature Reverse By-Pass Diodes Bias and Failures | Department...

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

    Reverse By-Pass Diodes Bias and Failures High Temperature Reverse By-Pass Diodes Bias and ... US & Japan TG 4 Activities of QA Forum Thermal Reliability Study of Bypass Diodes in ...

  11. University of Nevada Las Vegas LED Display Engineering

    SciTech Connect (OSTI)

    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.

  12. 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.

  13. Wisconsin LED Plant Benefits from Recovery Act | Department of Energy

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

    Stephen Graff Former Writer & editor for Energy Empowers, EERE What does this mean for me? LED lights emit more light, have a longer life and provide anywhere from 50 to 70 percent in energy savings. Rudd Lighting has seen a boost from cities tapping Recovery Act funds and seeking energy efficient lighting that will reduce costs. The BetalLED facility, which produced hundreds of thousands of LED products last year, employs about 600 people, and for every job in the plant, eight to 10 more

  14. Stage 1: Organizing the LEDS Process | Open Energy Information

    Open Energy Info (EERE)

    public and private sector capacity to support initiatives 2.4. Assess and improve the national GHG inventory and other economic and resource data as needed for LEDS development...

  15. Identify roles and responsibilities for LEDS process | Open Energy...

    Open Energy Info (EERE)

    public and private sector capacity to support initiatives 2.4. Assess and improve the national GHG inventory and other economic and resource data as needed for LEDS development...

  16. 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...

  17. LEDS Collaboration in Action Workshop | Open Energy Information

    Open Energy Info (EERE)

    on LEDS globally. The workshop goals were to: Convene low emissions development and low carbon growth decision-makers Promote South-South and North-South collaboration and...

  18. DOE Publishes Fact Sheet on LED Lighting and Health

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy has published a fact sheet that looks at what's known—and not known—about the effects of lighting on human health, with specific reference to LEDs. Entitled Lighting...

  19. Solid State Lighting LED Product Development and Manufacturing...

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

    ... The FY17 milestone remains a good target for luminaires. The typical price of a 3,500 lumen 2'x4' LED troffer at 100 lmW is currently about 90-95 per unit, however work is ...

  20. 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.

  1. Parking Savings Through LED Project for Iowa City | Department...

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

    grant and rebate from utility. City to save 66,000 annually with energy efficient LED lights in parking garages. Project will reduce energy usage by 1.4 million kWh...

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

    Office of Energy Efficiency and Renewable Energy (EERE)

    The U.S. Department of Energy (DOE) has released its latest report in a series analyzing markets where LEDs compete with traditional lighting sources. The new report, Adoption of Light-Emitting...

  3. 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.

  4. 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...

  5. LED Lighting on the National Mall | Department of Energy

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

    "Using energy-efficient LED light bulbs is an important way Americans can save money by saving energy," said Secretary Chu. "Investing in an American economy that is built to ...

  6. EECBG Success Story: Small Nebraska Town Welcomes LEDs and Energy...

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

    Welcomes LEDs and Energy Savings EECBG Success Story: Small Town Using Wind Power to Offset Electricity Costs EECBG Success Story: Out with the Old, In with the New: New...

  7. 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...

  8. Article Published on LED Lumen Maintenance and Light Loss Factors

    Broader source: Energy.gov [DOE]

    An article has been published in LEUKOS: The Journal of the Illuminating Engineering Society of North America (IES) that may be of interest to the solid-state lighting community. Entitled "Lumen Maintenance and Light Loss Factors: Consequences of Current Design Practices for LEDs," the article was written by Michael Royer of Pacific Northwest National Laboratory and discusses complications related to the lamp lumen depreciation (LLD) light loss factor and LEDs.

  9. 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.

  10. Color Maintenance of LEDs in Laboratory and Field Applications (Technical

    Office of Scientific and Technical Information (OSTI)

    Report) | SciTech Connect Synopsis: To date, consideration for parametric failure of LED products has largely been focused on lumen maintenance. However, color shift is a cause of early failure for some products, and is especially important to consider in certain applications, like museums, where visual appearance is critical. Example data collected by the GATEWAY program for LED lamps installed in museums shows that many have changed color beyond a reasonable tolerance well before their

  11. 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.

  12. Gravitational waves found, black-hole models led the way

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

    Gravitational waves found, black-hole models led the way Gravitational waves found, black-hole models led the way Gravitational waves were predicted by Einstein's theory of general relativity in 1916, and now, almost exactly 100 years later, the faint ripples across space-time have been found. February 11, 2016 A simulation of two merging black holes, creating gravitational waves. Photo courtesy of LIGO. A simulation of two merging black holes, creating gravitational waves. Photo courtesy of

  13. 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.

  14. Municipal Consortium LED Street Lighting Workshop Presentations and

    Energy Savers [EERE]

    Materials-Boston, MA | Department of Energy 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 Solid-State Street Lighting Consortium Workshop held in Boston August 2-3, 2012. Workshop Agenda DOE Municipal Solid-State Street Lighting Consortium James Brodrick, U.S. Department of Energy Boston's LED Street Lighting Initiative Joanne Massaro, Glenn Cooper, Matthew Mayrl,

  15. Municipal Consortium LED Street Lighting Workshop Presentations and

    Energy Savers [EERE]

    Materials-Dallas, TX | Department of Energy 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 Solid-State Street Lighting Consortium Workshop held in Dallas March 15-16, 2012. Presentations and Materials Workshop Agenda ONCOR LED Streetlight Pilot & Technical Evaluation Update Michael Navarro, ONCOR Reading, Understanding, and Applying the LM-80 Standard Chad

  16. Next-Generation LED Package Architectures Enabled by Thermally Conductive

    Energy Savers [EERE]

    Transparent Encapsulants | Department of Energy LED Package Architectures Enabled by Thermally Conductive Transparent Encapsulants Next-Generation LED Package Architectures Enabled by Thermally Conductive Transparent Encapsulants Lead Performer: Momentive Performance Materials Quartz, Inc. DOE Total Funding: $1,497,255 Cost Share: $512,700 Project Term: 10/1/2014 - 3/31/2016 Funding Opportunity: SSL R&D Funding Opportunity Announcement (FOA) (DE-FOA-0000973) Project Objective This

  17. Keeping Pace with LED Lighting Trends | Department of Energy

    Energy Savers [EERE]

    Keeping Pace with LED Lighting Trends Keeping Pace with LED Lighting Trends October 23, 2013 - 10:41am Addthis This year's SSL Market Introduction Workshop will take place in Portland, Oregon. | Photo courtesy of Travel Portland This year's SSL Market Introduction Workshop will take place in Portland, Oregon. | Photo courtesy of Travel Portland Jim Brodrick Jim Brodrick Lighting Program Manager Rapid advances in solid-state lighting (SSL) technology are reducing the cost, improving the

  18. 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.

  19. 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.

  20. 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.

  1. 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.

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

    SciTech Connect (OSTI)

    Krishnamoorthy, Sriram E-mail: rajan@ece.osu.edu; Akyol, Fatih; Rajan, Siddharth E-mail: rajan@ece.osu.edu

    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.

  3. Thermal Reliability Study of Bypass Diodes in Photovoltaic Modules (Poster)

    SciTech Connect (OSTI)

    Zhang, Z.; Wohlgemuth, J.; Kurtz, S.

    2013-05-01

    This paper presents the result of high-temperature durability and thermal cycling testing and analysis for the selected diodes to study the detail of the thermal design and relative long-term reliability of the bypass diodes used to limit the detrimental effects of module hot-spot susceptibility.

  4. CO.sub.2 optically pumped distributed feedback diode laser

    DOE Patents [OSTI]

    Rockwood, Stephen D. (Los Alamos, NM)

    1980-01-01

    A diode laser optically pumped by a CO.sub.2 coherent source. Interference fringes generated by feeding the optical pumping beam against a second beam, periodically alter the reflectivity of the diode medium allowing frequency variation of the output signal by varying the impingent angle of the CO.sub.2 laser beams.

  5. Enhanced Light Extraction from Organic Light Emitting Diodes - Energy

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

    Innovation Portal Photovoltaic Solar Photovoltaic Industrial Technologies Industrial Technologies Advanced Materials Advanced Materials Find More Like This Return to Search Enhanced Light Extraction from Organic Light Emitting Diodes Ames Laboratory Contact AMES About This Technology Technology Marketing SummaryAmes Laboratory researchers have developed a soft lithography microlens fabrication and array that enables more efficient organic light emitting diodes (OLEDs), improving their

  6. 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 kp 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.

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

    SciTech Connect (OSTI)

    Piprek, Joachim

    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.

  8. 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.

  9. Angle sensitive single photon avalanche diode

    SciTech Connect (OSTI)

    Lee, Changhyuk Johnson, Ben Molnar, Alyosha

    2015-06-08

    An ideal light sensor would provide exact information on intensity, timing, location, and angle of incoming photons. Single photon avalanche diodes (SPADs) provide such desired high (single photon) sensitivity with precise time information and can be implemented at a pixel-scale to form an array to extract spatial information. Furthermore, recent work has demonstrated photodiode-based structures (combined with micro-lenses or diffraction gratings) that are capable of encoding both spatial and angular information of incident light. In this letter, we describe the implementation of such a grating structure on SPADs to realize a pixel-scale angle-sensitive single photon avalanche diode (A-SPAD) built in a standard CMOS process. While the underlying SPAD structure provides high sensitivity, the time information of the two layers of diffraction gratings above offers angle-sensitivity. Such a unique combination of SPAD and diffraction gratings expands the sensing dimensions to pave a path towards lens-less 3-D imaging and light-field time-of-flight imaging.

  10. Eddy current gauge for monitoring displacement using printed circuit coil

    DOE Patents [OSTI]

    Visioli, Jr., Armando J.

    1977-01-01

    A proximity detection system for non-contact displacement and proximity measurement of static or dynamic metallic or conductive surfaces is provided wherein the measurement is obtained by monitoring the change in impedance of a flat, generally spiral-wound, printed circuit coil which is excited by a constant current, constant frequency source. The change in impedance, which is detected as a corresponding change in voltage across the coil, is related to the eddy current losses in the distant conductive material target. The arrangement provides for considerable linear displacement range with increased accuracies, stability, and sensitivity over the entire range.

  11. Highly Efficient Small Form Factor LED Retrofit Lamp

    SciTech Connect (OSTI)

    Steven Allen; Fred Palmer; Ming Li

    2011-09-11

    This report summarizes work to develop a high efficiency LED-based MR16 lamp downlight at OSRAM SYLVANIA under US Department of Energy contract DE-EE0000611. A new multichip LED package, electronic driver, and reflector optic were developed for these lamps. At steady-state, the lamp luminous flux was 409 lumens (lm), luminous efficacy of 87 lumens per watt (LPW), CRI (Ra) of 87, and R9 of 85 at a correlated color temperature (CCT) of 3285K. The LED alone achieved 120 lumens per watt efficacy and 600 lumen flux output at 25 C. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.90 at a power of only 5 watts. Compared to similar existing MR16 lamps using LED sources, these lamps had much higher efficacy and color quality. The objective of this work was to demonstrate a LED-based MR16 retrofit lamp for replacement of 35W halogen MR16 lamps having (1) luminous flux of 500 lumens, (2) luminous efficacy of 100 lumens per watt, (3) beam angle less than 40{sup o} and center beam candlepower of at least 1000 candelas, and (4) excellent color quality.

  12. Stress-induced piezoelectric field in GaN-based 450-nm light-emitting diodes

    SciTech Connect (OSTI)

    Tawfik, Wael Z.; Hyeon, Gil Yong; Lee, June Key

    2014-10-28

    We investigated the influence of the built-in piezoelectric field induced by compressive stress on the characteristics of GaN-based 450-nm light-emitting diodes (LEDs) prepared on sapphire substrates of different thicknesses. As the sapphire substrate thickness was reduced, the compressive stress in the GaN layer was released, resulting in wafer bowing. The wafer bowing-induced mechanical stress altered the piezoelectric field, which in turn reduced the quantum confined Stark effect in the InGaN/GaN active region of the LED. The flat-band voltage was estimated by measuring the applied bias voltage that induced a 180 phase shift in the electro-reflectance (ER) spectrum. The piezoelectric field estimated by the ER spectra changed by ?110?kV/cm. The electroluminescence spectral peak wavelength was blue-shifted, and the internal quantum efficiency was improved by about 22% at a high injection current of 100?mA. The LED on the 60-?m-thick sapphire substrate exhibited the highest light output power of ?59?mW at an injection current of 100?mA, with the operating voltage unchanged.

  13. 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.

  14. Text-Alternative Version: Maintenance Practices for LED Streetlights |

    Energy Savers [EERE]

    Department of Energy Maintenance Practices for LED Streetlights Text-Alternative Version: Maintenance Practices for LED Streetlights Bruce Kinzey:So again, I want to welcome everyone to another MSSLC webinar. And we have a great one lined up today. At this point everyone is familiar with the fact that the solid-state street lighting is being installed by the thousands, hundreds of thousands in fact, around the country. I think everyone's also pretty familiar with the kinds of energy savings

  15. Save Money with LED Holiday Light Strings | Department of Energy

    Energy Savers [EERE]

    Money with LED Holiday Light Strings Save Money with LED Holiday Light Strings December 1, 2009 - 11:19am Addthis Allison Casey Senior Communicator, NREL It's hard to believe, but the holidays are in full swing and many of you are starting to decorate your homes. Those of you who started around Halloween are probably feeling pretty smart because you got your decorating done while the weather was nice. I see you there, snacking on your Thanksgiving leftovers, laughing at me shivering in the cold

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

    Office of Environmental Management (EM)

    LED Holiday Lights: Festive, Safe, and Efficient! LED Holiday Lights: Festive, Safe, and Efficient! December 2, 2010 - 4:34pm Addthis Andy Oare Andy Oare Former New Media Strategist, Office of Public Affairs Ed. Note cross posted from the Energy Savers Blog. Written by Allison Casey This week brings a day that many people look forward to all year -- and I'm not talking about Thanksgiving, or Black Friday. I'm talking about that magical day when it's finally okay to drag the dusty boxes from the

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

    Office of Environmental Management (EM)

    LED Holiday Lights: Festive, Safe, and Efficient! LED Holiday Lights: Festive, Safe, and Efficient! November 23, 2010 - 6:30am Addthis Allison Casey Senior Communicator, NREL This week brings a day that many people look forward to all year-and I'm not talking about Thanksgiving, or Black Friday. I'm talking about that magical day when it's finally okay to drag the dusty boxes from the basement or attic, to lovingly sort and display your decorations, to untangle your light strings and set up the

  18. 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.

  19. 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.

  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. 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.

  2. 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.

  3. Microlens frames for laser diode arrays

    DOE Patents [OSTI]

    Skidmore, Jay A.; Freitas, Barry L.

    1999-01-01

    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.

  4. 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.

  5. 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.

  6. Small Nebraska Town Welcomes LEDs and Energy Savings

    Broader source: Energy.gov [DOE]

    Tecumseh’s town historic town square is home to the city hall, courthouse, post office, and during the summer months—a farmers market. Now, this historic square, built in the 1850’s, is about to become home to something new: LED lights.

  7. 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).

  8. CALiPER Application Summary Report 15. LED Floodlights

    SciTech Connect (OSTI)

    none,

    2012-05-01

    This report analyzes the independently tested performance of 10 LED floodlights purchased between August and December 2011. The group included a wide range of products, both physically and in performance characteristics, which mirrors the nearly indefinite range of conventional luminaires designated as floodlights.

  9. EM-Led Radiological Incident Response Program Receives Honors

    Broader source: Energy.gov [DOE]

    A program led by EM’s Carlsbad Field Office (CBFO) that coordinates analytical capabilities throughout DOE for response to potential national radiological incidents recently received recognition for the best-in-track poster at a waste management conference earlier this year.

  10. 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.

  11. 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.

  12. Understanding Drooping Light Emitting Diodes CEEM | U.S. DOE...

    Office of Science (SC) Website

    Understanding "droop" may result in cheaper, more efficient LEDs; LEDs are more energy ... indium in Indium Gallium Nitride (InGaN) green LEDs caused a decrease in light intensity. ...

  13. High efficiency single Ag nanowire/p-GaN substrate Schottky junction-based ultraviolet light emitting diodes

    SciTech Connect (OSTI)

    Wu, Y.; Li, X.; Xu, P.; Wang, Y.; Shen, X.; Liu, X.; Yang, Q.; Hasan, T.

    2015-02-02

    We report a high efficiency single Ag nanowire (NW)/p-GaN substrate Schottky junction-based ultraviolet light emitting diode (UV-LED). The device demonstrates deep UV free exciton electroluminescence at 362.5?nm. The dominant emission, detectable at ultralow (<1??A) forward current, does not exhibit any shifts when the forward current is increased. External quantum efficiency (EQE) as high as 0.9% is achieved at 25??A current at room temperature. Experiments and simulation analysis show that devices fabricated with thinner Ag NWs have higher EQE. However, for very thin Ag NWs (diameter?LEDs.

  14. 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.

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

    Office of Scientific and Technical Information (OSTI)

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

  16. Demonstration Assessment of Light-Emitting Diode Roadway Lighting...

    Office of Scientific and Technical Information (OSTI)

    Roadway Lighting on the FDR Drive in New York, New York Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode Roadway Lighting on the FDR ...

  17. Megahertz organic/polymer diodes (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    flows through the layers in one direction when a voltage is applied in one direction. ... the first layer, the diode is capable of high frequency rectifications on the order of ...

  18. Demonstration Assessment of Light-Emitting Diode Roadway Lighting...

    Office of Scientific and Technical Information (OSTI)

    Roadway Lighting on the FDR Drive in New York, New York Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode Roadway Lighting on the FDR...

  19. 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.

  20. Parameter Estimation for Single Diode Models of Photovoltaic...

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

    10 11 2. SINGLE DIODE MODELS A model for the electrical characteristic of a solar cell (e.g., 2, Eq. 1) can be derived from physical principles (e.g., 3) and is...