White Papers
White Paper: Serviceable Luminaires in a Circular Economy from LightingEurope
LightingEurope is proactively exploring the business opportunities that a Circular Economy presents for the lighting industry, as well as the framework conditions required for its successful rollout in the lighting sector.
This paper focuses on luminaires, services and design for serviceability and their potential for the lighting industry.
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White Paper: Polymeric Systems Bring Clarity to Optical Applications
Some optical assembly applications require optical clarity across a certain wavelength, while others require an opaque coating. Optical grade epoxies, silicones and UV curable coatings provide the versatility to adhere well to a wide variety of substrates and display the critical performance properties required. Learn more about optical transmission, refractive indices, temperature and humidity testing, and more, plus the roles these measurements play in choosing an effective and reliable optical polymer system.
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White Paper: FluxGage - A Photometric Test System for LED Luminaires Based on Solar Panels
We present a novel photometric test system for LED luminaires. The new photometric system called „FluxGage“ uses solar panels to detect and measure light. By placing a diffuser and a black pinhole array over a solar panels we achieve a detection surface which is also an absorber. This enables the system to be the same size as the DUT (Device Under Test), as opposed to an integrating sphere which is at least 3 times larger than the DUT. Simulations and experimental results show that this system can measure total flux with an uncertainty of 4.3%. The demonstrated system is used in 2π geometry. The system measures total flux, color parameters (CCT, CRI, chromaticity, etc.) and flicker.
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White Paper: Extending the Life-Time of LEDs
Choosing the correct protection media for LED devices to improve lifetime and performance.
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Smartcells - Enabling Fast and Accurate Electronics Thermal Design
This white paper introduces the concept of SmartCells™ in the context of Computational Fluid Dynamics (CFD) simulation software. They exist in FloTHERM XT™, a CAD enabled electronics cooling simulation tool supplied by Mentor Graphics (Ref 1). This document will explain what they are, how they differ from other meshing approaches employed in the CFD industry, and their benefits to CFD users and electronics thermal designers.
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White Paper: Shaping LED Diffuser Performance with Polycarbonate Materials
The LED lighting market continues to grow, yet consumers are accustomed to the soft white diffused light from incandescent bulbs. To speed up adoption, manufacturers are utilizing plastic materials containing diffusion additives to offset harsh LED illumination and eliminate hot spots. It’s important to choose the correct diffusion plastic to meet to meet transmission, color and UL requirements. In this paper, we examine how plastic selection, a diffusion package and color help designers achieve the desired look for their application.
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White Paper: Predicting Scatter of Light Shaping Diffuser® Angles Using Luminit’s Proprietary Optical Model and OpticStudio
Luminit has developed a proprietary scatter model for users of Zemax. Unlike conventional optical design programs that provide bulk scatter and surface scatter models that “predict” output distribution, Luminit’s proprietary optical model accurately calculates surface effects so users can choose the Light Shaping Diffuser (LSD) angle that offers the most optimized performance. This white paper describes the characteristics of the LSD scatter model and the level of accuracy that can be achieved during this critical stage of the design cycle.
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Manufacturability of OLED Encapsulation and Light Extraction
Applications for OLEDs in lighting are opening unique possibilities for designers; however, the organic materials make OLEDs more fragile than LEDs. A higher-index Luminit Light Shaping Diffuser® developed into a barrier film could be an excellent substrate for OLEDs, encapsulating them while simultaneously supporting them.
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WHITE PAPER: "LED Reflector and Lens Simulation using TracePro® Illumination Design and Analysis Software"
TracePro® allows users to design, analyze, and optimize LED lighting systems using software simulation prior to building hardware. The resultant accuracy of these models depends on the accuracy of the components that make up the model. These include light source characteristics, surface and material properties, and model geometry.
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Litecool Demonstrates that Narrow Beam LED Packages Are a Real Possibility
Litecool has been working on various LED package designs to give luminaire manufacturers an LED package that doesn’t need any further lensing or reflectors to give the desired beam patterns for lighting applications.
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BluGlass Demonstrates Improved Performance Results for Green RPCVD Manufactured p-GaN LEDs
BluGlass has succeeded in its initial experimentation of applying low temperature RPCVD p-GaN to Green LED applications with highly promising results. These results show that the green LEDs produced using RPCVD p-GaN are demonstrating greater efficiency than the BluGlass grown MOCVD benchmark LEDs using the exact same MOCVD grown multi-quantum wells (MQWs), the critical light emitting region of an LED device.
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TRIAC Dimmable, Isolated LED Driver with High Power Factor Needs No Opto-Isolators
As environmental concerns over traditional lighting in-crease and the price of LEDs decreases, high power LEDs are fast becoming a popular lighting solution for offline applications. In order to meet the requirements of offline lighting - such as high power factor, high efficiency, isolation and TRIAC dimmer compatibility - prior LED drivers used many external discrete components, resulting in cumbersome solutions. By Wei Gu Applications Engineering Section Leader at Linear Technology demonstrates how new solutions reduce complexity while improving performance.
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WHITE PAPER: "High Intensity UV LED Sources Enabled by Next Generation Substrates"
Thermal management of high-power UV LEDs is substantially more demanding than for white LEDs. This arises due to their lower efficacy combined with the end use requirement for intense light sources. Critical to the thermal management of densely packed LED arrays is the substrate the semiconductors are mounted on. This whitepaper investigates how next generation Nanoceramic substrates can benefit the LED industry and presents a case study of a 75W UV LED module, just 2cm².
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WHITE PAPER: "Accurate LED Source Modeling Using TracePro"
Modern optical modeling programs allow product design engineers to create, analyze, and optimize LED sources and LED optical systems as a virtual prototype prior to manufacturing the actual product. The precision of these virtual models depends on accurately representing the components that make up the model, including the light source.
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The Future of More Efficient LEDs and Lasers Probably Starts in 2D
The future of electronics could lie in a material from its past, as researchers from The Ohio State University work to turn germanium - the material of 1940s transistors - into a potential replacement for silicon.
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Osram Improves Efficiency of Blue LED Chips by Reducing Forward Voltage
Osram Opto Semiconductors has achieved one of the best values in the world in terms of forward voltage for blue high-current chips. This has led to an increase in efficiency of up to eight percent. Optimized InGaN chips (Indium-Gallium-Nitride) featuring UX:3 chip technology are the basis for blue or white LEDs – and are already used in production. Osram experts also see considerable potential for reducing the value by a further 20 to 30 millivolts (mV) by the summer of 2015 – offering a further boost in efficiency.
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Universities Develop Novel LEDs by Band-Structure Engineering in van der Waals Heterostructures
Semi-transparent, flexible electronics are no longer just science-fiction thanks to graphene’s unique properties, University of Manchester researchers have found. Published in the scientific journal Nature Materials, University of Manchester and University of Sheffield researchers show that new 2D ‘designer materials’ can be produced to create flexible, see-through and more efficient electronic devices including semi-transparent LEDs.
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Holst Centre and Flex-o-Fab Take the First Step Towards "Lighting by the Mile"
Researchers from the EU-funded Flex-o-Fab project have successfully fabricated working OLED devices on a flexible barrier layer produced in a roll-to-roll (R2R) process. Produced on a PET plastic film, this breakthrough is a significant first step towards taking flexible OLEDs ‘from lab to fab’ and hence to commercial production. It draws on technical developments achieved within both Flex-o-Fab and Holst Centre’s joint research program into high-performance flexible barriers for organic electronics.
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Ending the Invisible Threat - Confronting the LED Flickering Issue
One of the topics in 2014 International LIGHTFAIR DOE training was “SSL Flicker Fundamentals and Why We Care“ (Michael Poplawski and Naomi Miller 2014),this reignited the industry’s discussion on light modulation. This topic was already raised by ASSIST earlier, where research on human’s level of tolerance to high-frequency flickers have been done and published in several lighting magazines by Rebekah Mullaney, hoping to encourage LED manufacturers and distributors to put more emphasis on finding a permanent solution that is more suitable for people’s well-being. - Andy Fei and Nina Chen from ALT-LED summarize these flicker research results and explain how to avoid flicker issues.
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LpS 2014 Scientific Award Winner Article: New Binning Strategy for White LEDs
After having recognized the deficiencies of the ANSI binning strategy, which is based on the visually false magnification of MacAdam’s ellipses, Dr. Peter Bodrogi and Prof. Tran Quoc Khanh from the Technical University Darmstadt propose a new binning strategy based on a so-called semantic interpretation to describe and easily communicate the magnitude of acceptable chromaticity differences.
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Compute Simulation Sheds Light On Why Blue LEDs Are So Tricky To Make
![New research from academics from the University of Bath Department of Chemistry has uncovered the mystery of why blue light-emitting diodes (LEDs) are so difficult to make: (1) Calculated spin density resulting from (a) a Mg0Ga-associated hole localized on a neighboring N in the basal plane, (b) a Mg0Ga-associated hole localized on a neighboring axial N, and (c) a N vacancy. Light gray (green) [darker gray (blue)] spheres represent Ga (N) atoms. The darkest gray sphere represents a Mg atom in (a) and (b) (purple) and a vacancy in (c) (orange). Spin densities are indicated by (red) isosurfaces of density (au) 0.05, 0.025, and 0.01 for (a) and (b) and 0.01, 0.005, 0.0025 for (c). (2) Formation energy of VN (black line) and MgGa [light gray (red) line] as a function of Fermi energy above the VBM. Anion-rich conditions are assumed. The position of the conduction band minimum (CBM) is indicated by the broken line. For each value of Fermi energy, only the most stable defect charge state is shown, with a change in slope indicating a change in charge state](https://www.led-professional.com/technology/light-generation/compute-simulation-sheds-light-on-why-blue-leds-are-so-tricky-to-make/University%20of%20Bath%20Department%20of%20Chemistry%20has%20uncovered%20the%20mystery%20of%20why%20blue%20light-emitting%20diodes%20-LEDs-%20are%20so%20difficult%20to%20make.jpg/@@images/dd63b2df-d470-4f03-8bb0-9457a16f63d6.jpeg "New research from academics from the University of Bath Department of Chemistry has uncovered the mystery of why blue light-emitting diodes (LEDs) are so difficult to make: (1) Calculated spin density resulting from (a) a Mg0Ga-associated hole localized on a neighboring N in the basal plane, (b) a Mg0Ga-associated hole localized on a neighboring axial N, and (c) a N vacancy. Light gray (green) [darker gray (blue)] spheres represent Ga (N) atoms. The darkest gray sphere represents a Mg atom in (a) and (b) (purple) and a vacancy in (c) (orange). Spin densities are indicated by (red) isosurfaces of density (au) 0.05, 0.025, and 0.01 for (a) and (b) and 0.01, 0.005, 0.0025 for (c). (2) Formation energy of VN (black line) and MgGa [light gray (red) line] as a function of Fermi energy above the VBM. Anion-rich conditions are assumed. The position of the conduction band minimum (CBM) is indicated by the broken line. For each value of Fermi energy, only the most stable defect charge state is shown, with a change in slope indicating a change in charge state")
Researchers in our Department of Chemistry have collaborated with groups at University College London (UCL) and Daresbury to uncover the mystery of why blue light-emitting diodes (LEDs) are so difficult to make, by revealing the complex properties of their main component – gallium nitride – using sophisticated computer simulations.
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Zhaga Consortium Starts Work on New Specification for COB LED Arrays
In response to feedback from a broad range of stakeholders, the Zhaga Consortium, which develops specifications for
interchangeable LED light sources, is now working on a new Book that will include Chip-on-Board (COB) LED arrays. The new Zhaga Book will specify a family of six rectangular or square LED modules with different dimensions.
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Thermoresponsive PDLC Coating for Smart CCT-Tunable LED Applications
When the 2014 Nobel Prize in physics was awarded this October to three Japanese-born scientists for the invention of blue light emitting diodes (LEDs), the prize committee declared LED lamps would light the 21st century. Now researchers from the Netherlands propose a novel way to ensure the lights of the future not only are energy efficient but also emit a cozy warmth. Cornelissen and his colleagues from the Eindhoven University of Technology, Netherlands describe their new LEDs in a paper published in The Optical Society's (OSA) open-access journal Optics Express.
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WHITE PAPER: "Optimization of LED Lens Components using TracePro® Illumination Design and Analysis Software"
TracePro® is award-winning opto-mechanical design software for layout, optimization, & analysis of illumination systems. This white paper illustrates how TracePro’s 2D & 3D optimization utilities are designed to help CAD designers without optical engineering expertise design a variety of LED optical components – including practical examples. The capabilities of TracePro lead the designer through a process to maximize the technical merits of the device/system in the shortest amount of time.
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WHITE PAPER: Intelligent Over Temperature Protection for LED Lighting Applications
LED lighting is becoming increasingly popular. It offers numerous advantages over conventional lighting, but there are still some issues. One is thermal management. Bernd Pflaum and Hakan Yilmazer from Infineon Technologies explain how LED driver ICs with smart over temperature protection help to increase lifetime and optimize system costs of LED lighting systems.
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Osram Opto Demonstrates "3D nano LEDs" for White Light and Sees Series Maturity in Coming Years
By making use of nanotechnology, Osram hopes to produce significantly more LED chips with its existing production plant. Osram researchers have for the first time succeeded in manufacturing a so-called "3D nano LED" for white light. The productivity boost is possible due to the special surface characteristics of the LED chip – in contrast to today's standard models, this is not smooth but consists of many adjacent, microscopically small columns with a three-dimensional structure, thus increasing its light-generating area. The new technology is expected to achieve series maturity in coming years, and Osram would then be one of the first companies to use this technology.
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Yole Releases New Nanowire LED IP Study - Startups Compete with Asian LED Giants in the IP Landscape
Asian giants Samsung, Panasonic and LG are the top three patent assignees for Nanowire LED technology. Facing them are several startups including glo, Aledia and Ecospark, which between them have raised more than $150M - thus confirming their serious interest in this field. However, these newcomers face strong technological challenges.
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GaN-on-Silicon Substrate Patent Investigation - Knowmade & Yole See More Players on the Playground
GaN-on-Si technology appeared naturally as an alternative to GaN-on-Sapphire—the main stream technology for LED applications. Today, despite potential cost benefits, the mass adoption of GaN-on-Si technology for LED applications remains unclear. Most major LED makers have a patenting activity related to GaN-on-Si technology, but so far, few have made it the core of their strategy and technology roadmap. Contrary to the LED industry, we expect GaN-on-Si to be widely adopted by Power Electronics and RF applications because of its lower cost and CMOS compatibility.
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EEPCA & LightingEurope Announce ENEC+ - The First European Mark That Certifies the Initial Performance of LEDs and Other Luminaires
EEPCA, the European Electrical Products Certification Association, in cooperation with LightingEurope, today announced the launch of ENEC+, the first pan-European mark capable of certifying the initial performance of traditional and LED luminaires. The new performance rating provides the market with certification as to the compliance of LED light fixtures and other luminaires, proving compliance with European safety standards and ensuring the reliability of their stated performance characteristics at the beginning of their life cycle.
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Zhaga Starts Work on New Books
The Zhaga Consortium, a global lighting-industry organization that is enabling interchangeable LED light engines, has started the development of three new interface specifications, known as Books. The new Books are designated numbers 9, 10 and 11.
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