LED professional Review (LpR) - Articles

Resources | LpR Article | Organization News | LightingEurope | Applications | Dec 17, 2018

Evaluating Performance of LED-Based Luminaires

Evaluating Performance of LED-Based Luminaires LpR 69 Article, page 48: The wide spread of performance data supplied by manufacturers make it difficult for the professional user to reach an “apple-to-apple” comparison, especially if the data is not based on standardized metrics. This is however critical for the preparation of lighting projects or tender specifications. Experts from LightingEurope have therefore developed a guidance document which recommends a fixed set of performance data for LED based luminaires, with particular emphasis to the useful life and the data which is necessary for lighting application design. Read more »

Resources | LpR Article | Standardization & Regulation | Zhaga | Connected Lighting | Smart Lighting & IoT | Dec 14, 2018

Zhaga Enables Mechanical IoT-Upgradability for Outdoor LED Lighting Fixtures

Zhaga Enables Mechanical IoT-Upgradability for Outdoor LED Lighting Fixtures LpR 69 Article, page 42: The Zhaga Consortium is a global association of lighting companies that is standardizing LED luminaire components interfaces. The latest specification from Book 18 defines a standardized interface between outdoor LED luminaires and modules for sensing and communication. Dee Denteneer, Zhaga Secretary General, explains how the New Book 18 helps bring the Internet of Things to the outdoor lighting market via smart, upgradeable, future-proof fixtures. Read more »

Resources | LpR Article | Research News | CIE | Applications | Dec 12, 2018

How to Use the Technologies for Adaptive Lighting

How to Use the Technologies for Adaptive Lighting The technologies to provide adaptive lighting are already in the marketplace and are accepted by some jurisdictions. Nonetheless, we have an inadequate understanding of how best to use these technologies, meaning that installations might not serve users well, and in the worst case, might lead to harm. Lighting researchers can generate the knowledge needed to support the best application of adaptive lighting technologies. The International Commission on Illumination (CIE) understands the importance and urgency to deal with problems of adaptive, dynamic and intelligent lighting in all application fields. Hence, this topic is a highlight of CIE’s research strategy. Read more »

Resources | LpR Article | Technologies | Horticulture | UV | Dec 01, 2018

UV LED Technology for Emerging Applications in Agriculture

UV LED Technology for Emerging Applications in Agriculture The Ultraviolet (UV) LED market has expanded five-fold in the past decade and is projected to grow to over $1 billion by 2025. A key trend expected to influence the market is the ability to expand into new applications, including agriculture. UV light, at proper frequency and dose, can increase the production of active substances in medicinal and traditional plants and it can also help maintain a healthy growing environment. But to fully take advantage of UV LEDs, some major re-design considerations are required. Terrance Berland, CEO of the Violet Defense Group, the parent company of Violet Gro, will explain which considerations these are; for instance, why it is crucial to incorporate the appropriate lens material. Read more »

Resources | LpR Article | Research Reports | Smart Lighting & IoT | Nov 26, 2018

Challenges of the Integration of Lighting Systems and Components in IoT

Challenges of the Integration of Lighting Systems and Components in IoT LpR 68 Article, page 50: Following the rapid penetration of LEDs, lighting is now becoming integrated into the Internet of Things. Over the past three years a consortium of leading European companies worked on the OpenAIS project, which was partly funded by the EU within the Horizon 2020 program, and now showing the results working at a full size demonstrator. In this follow up article to the introduction article of LpR 67, Ben Pronk, System Architect at Signify, and Stefan Verbrugh, Project Manager at Signify and Work Package leader in OpenAIS give deeper insight into the project. They explain the lighting specific challenges, describe the generic challenges for IP controlled lighting and present the approach to these challenges. They conclude by summarizing the findings from the pilot. Read more »

Resources | LpR Article | Research | Light Generation | Laser Technology | Nov 19, 2018

Laser Technology for Lighting Applications: A Review and Analysis of a Promising Technology

Laser Technology for Lighting Applications: A Review and Analysis of a Promising Technology LpR 68 Article, page 44: LEDs are currently the dominating light source: efficient and cost effective. But LEDs also have some drawbacks. Another interesting technology developed slowly in the shadow of LEDs and has become an interesting solution for some specific applications: GaN based blue solid state laser devices. Although this technology offers some very interesting advantages, it also has challenges. Nicola Trivellin, Matteo Buffolo, Carlo De Santi, Gaudenzio Meneghesso, Enrico Zanoni and Matteo Meneghini from the University of Padova and its spin-off LightCube have been working toward the development of experimental systems and demonstrators and disclose their findings of the comparison between LED and LD systems. Read more »

Resources | LpR Article | Research | Manufacturing | LED Modules | Nov 05, 2018

A Study on Aerosol Jet Printing in LED Module Manufacturing

A Study on Aerosol Jet Printing in LED Module Manufacturing LpR 68 Article, page 38: LED module manufacturing technologies have certainly improved over the last few years but the requirements have also increased. More components are packed on today’s modules causing additional thermal stress, and, at the same time, the demand for lower cost challenges module manufacturers. So the (re-) search for new materials and new manufacturing processes and manufacturing technologies is still on. Paul Hartmann, Director of the Institute of Surface Technologies and Photonics at the Joanneum Research Forschungsgesellschaft m.b.H., and his team, Andreas Rudorfer, Martin Tscherner, Christian Palfinger, Frank Reil, Franz P. Wenzl with Ioannis E. Seferis, Eugeniusz Zych from the Faculty of Chemistry of the University of Wroclaw investigated the opportunities of aerosol jet printing and proved the applicability for alternative ways of phosphor deposition and integration and to replace wire bonding of dies. Read more »

Resources | LpR Article | Research Reports | Smart Lighting & IoT | Oct 29, 2018

Integrating Lighting in the Internet of Things

Integrating Lighting in the Internet of Things LpR 67 Article, page 80: Following the rapid penetration of LEDs, lighting now becomes integrated into the Internet of Things. Over the past three years a consortium of leading European companies worked on the OpenAIS project, partly funded by the EU within the Horizon 2020 program. Now showing the results, the consortium is working on a full size demonstrator. Ben Pronk, System Architect at Philips Lighting Research, and Frank van Tuijl, Project Manager at Philips Lighting show how OpenAIS creates an open ecosystem to enable a wider community to deliver the smartness of light and they explain how it is possible to adapt the system to cater to the diversity of people and demands. Read more »

Resources | LpR Article | Technologies | Optics | Nano-Optics | Oct 22, 2018

LED Lighting Requires New Approaches in Optics

LED Lighting Requires New Approaches in Optics LpR 67 Article, page 88: Even though LED technology has been established LEDs still need new approaches in electronics, thermal management or optics to make complete use of their advantages. Marek Škereň, Chief Technology Officer of IQ Structures, explains how new optical devices, with the trade name Nanoptiqs, based on principles of diffraction are applied to achieve improved performance of white light illumination systems. This unique solution is based on full control over the modulation of material and geometric properties of the optical elements at a nano-level. A combination of complex transmission diffractive elements, with specially designed systems of micro-reflectors (produced using an innovative mass-production technique) is also presented as a promising flexible building unit for the construction of new generation luminaires. Read more »

Resources | LpR Article | SciPiL | Micro-Optics | Manufacturing | Oct 15, 2018

Roll-to-Roll UV Nanoimprint Lithography for Large-Area Nano- and Micro-Structuring of Flexible Substrates

Roll-to-Roll UV Nanoimprint Lithography for Large-Area Nano- and Micro-Structuring of Flexible Substrates LpR 67 Article, page 50: Cost and time-efficient methods for the fabrication of optical elements are highly desirable in the field of lighting. Imprinting optical structures in combination with large area fabrication turns out to become an effective approach in this regard. In particular roll-to-roll UV nanoimprint lithography (R2R-UV-NIL) has a large potential to set new benchmarks for the fabrication of miniaturized, low-cost and low-weight optics that can be applied in many fields of applications. In the following, the Joanneum Research Forschungsgesellschaft m.b.H team, Claude Leiner, Stephan Ruttloff, Dieter Nees, Anja Haase, Ladislav Kuna, Wolfgang Nemitz, Franz-Peter Wenzl, Christian Sommer, Barbara Stadlober and Ursula Palfinger, led by Paul Hartmann, demonstrates the maturity of the related process chain, combining optical design, direct laser lithography, step&repeat imprinting for shim fabrication and R2R reproduction. Read more »

Resources | LpR Article | Research | Thermal Management | Testing | Oct 08, 2018

Automatic Panel Level Transient Thermal Tester

Automatic Panel Level Transient Thermal Tester LpR 67 Article, page 44:The thermal resistance junction in case is an important parameter for the reliability of LEDs because degradation of the LED is temperature driven. Simulation and testing has advanced over the past few years but transient thermal analysis (TTA), which is required to understand the thermal transfer path, is especially work and time consuming - and not automated. Gordon Elger, Professor for Electronic Manufacturing Technologies, Technische Hochschule Ingolstadt, and his co-authors, Maximilian Schmidt, Alexander Hans, and Dominik Müller, present and discuss an automatic panel level TTA tester. They explain the challenges and the solution and demonstrate the applicability of using LED test board-panels. Read more »

Resources | LpR Article | Special Applications | Aeronautics | Reliability | Sep 13, 2018

Abrasion in Transparent Lens Materials for Exterior Aircraft Lighting

Abrasion in Transparent Lens Materials for Exterior Aircraft Lighting Research, Engineering, and Quality Assurance at Kopp Glass, reports how Taber abrasion and high-velocity particulate testing was performed on three different jet aircraft lens materials, including: heat strengthened borosilicate glass (Kopp 9000), hard-coated polycarbonate, and aviation grade acrylic (Makrolon AR and Plexiglas II UVA). Read more »

Resources | LpR Article | Engineering | LEDs | Reliability | Aug 06, 2018

Electrical Over Stress - How to Prevent an LED Failing Earlier than Expected

Electrical Over Stress - How to Prevent an LED Failing Earlier than Expected Article from LpR 66, page 70: While LEDS are, in general, very robust, failures still happen due to electrical over stress. Mauro Ceresa, EMEA Field Application Engineer Manager at Cree, will cover all aspects related to electrical over stress, or when an LED fails due to being subjected to a voltage beyond its specification limits. He will explain why the failure occurs and how to prevent this from happening. The article will explain the fundamental aspects of a good PCB layout design and how this is linked to the longevity of an LED. Read more »

Resources | LpR Article | Research | Life-Time | Simulation Tools | Jul 30, 2018

Lifetime- and Economic Efficiency Simulation of LED Luminaires in Dymola/Modelica

Lifetime- and Economic Efficiency Simulation of LED Luminaires in Dymola/Modelica Article from LpR 66 | page 40: The lifetime of an LED system is usually specified by the LM-80 report using the TM-21 method. Unfortunately, this value is solely valid for one specific application. Sebastian Hämmerle and Thomas Schmitt from the University of Applied Sciences in Vorarlberg developed a new open-source Modelica library for dynamic simulation of LEDs: The DynaLed library. The aim of the work was to evaluate the lifetime and the corresponding economic efficiency of LEDs in dynamic operation by means of the LM-80 report and according to the TM-21 calculation method. Furthermore, it should be possible to use the library for component dimensioning, e.g. the heatsink. The primary task was to develop simulation models which can be parametrized with manufacturer information, e.g. the datasheet, but still provide sufficient accuracy. As an application example an LED louvre luminaire (Article Code: 29001077) from LEDON Lamp GmbH was simulated utilizing the developed library. At the end, results from the lifetime- and the economic efficiency simulation were discussed. Read more »

Resources | LpR Article | Engineering | Lifetime | Drivers | Jul 23, 2018

Method and Circuit to Maintain Constant Light Output for LED Luminaires

Method and Circuit to Maintain Constant Light Output for LED Luminaires Article from LpR 66 | page 80: It is difficult to accurately predict the lifetime or the light output degradation of LED luminaires. A Constant Light Output (CLO) operation is implemented in some of the latest drivers. However, there are many factors that require a different algorithm in terms of time rate and forward current values that are usually not taken into account. Prof.Dr.Eng. Stelian Matei, from the Photometry and Electromagnetic Compatibility Laboratory at Electromagnetica SA, proposes and explains a new method is maintaining the luminous flux over the lifetime of the LED luminaire, considering the luminaire global light degradation. Read more »

Resources | LpR Article | Commentary | Safety | Light Sources | Jul 20, 2018

Blue Light Hazard - How Dangerous Is SSL Lighting?

Blue Light Hazard - How Dangerous Is SSL Lighting? Modern Solid State Lighting (SSL) technology has long since found its way into our normal working and living environments. In the early phases, consumers were most concerned with lifetime, pricing and light quality of the new LED-based light sources. Now they have become almost ubiquitous, a focus has been placed on safety. At the recent Light+Building exhibition topics such as photobiological safety and blue light hazard (BLH) were highly ranked among both visitors and exhibitors. Read more »

Resources | LpR Article | Light Generation | LEDs | Human Centric Lighting | Jul 02, 2018

A Near Infrared Enhanced LED Lighting Approach

A Near Infrared Enhanced LED Lighting Approach With the evolution of LED lighting, one topic has come more and more in the focus of the lighting industry: Human Centric Lighting (HCL). While HCL is not clearly defined, a common understanding is that this is light and lighting that supports health and the well-being of humans. Some new proposals are going beyond the approach of providing just visible light in adequate quality, but also to providing invisible radiation, UV and/or NIR that support health and well-being. Some research and the evolution of humans show clear evidence for positive effects of this kind of illumination. Scott Zimmerman, CEO at Silas, presents a new approach that adds NIR radiation to LED illumination. He explains the background of this idea, how it also improves the quality of visible light and discusses the health benefits. Read more »

Resources | LpR Article | Research | Light Generation | LEDs | Nanowire | Jun 27, 2018

Full-Color InGaN/AlGaN Nanowire Light-Emitting Diodes for SSL and Displays

Full-Color InGaN/AlGaN Nanowire Light-Emitting Diodes for SSL and Displays III-nitride based nanowire light-emitting diodes (LEDs) have received a staggering response as a future candidate for solid-state lighting and full-color displays due to their unique and exceptional features including drastically reduced polarization fields, dislocation densities as well as the associated quantum confined Stark effect (QCSE) on account of their effective strain relaxation. Moab Rajan Philip and his supervisor Dr. Hieu P Nguyen in the Nano-Optoelectronic Materials and Devices Laboratory at the New Jersey Institute of Technology (NJIT) present astonishing ideas to fabricate and control the color emission of III-nitride nanowire LEDs via molecular beam epitaxy (MBE) growth techniques. The advantage of such LEDs and their characteristics is also discussed. Read more »

Resources | LpR Article | Automotive | Driver IC | Jun 01, 2018

Flicker-Free Control of Individual LEDs in Matrix Headlights

Flicker-Free Control of Individual LEDs in Matrix Headlights LEDs combine design flexibility with practical, robust circuitry, enabling automotive designers to produce striking headlight designs matched by exceptionally long life and performance. Keith Szolusha, Sr. Design Leader for LED driver products at Linear Technology, and now part of Analog Devices explains how automobile designers are increasingly incorporating LEDs in lighting because they can be arranged in distinctive eye-catching designs - helping distinguish new models from old, or high end from economy. Read more »

Resources | LpR Article | Technologies | Applications | May 02, 2018

Multi-Pixel LED Technology Opens New Horizons for Smart Lighting Applications

Multi-Pixel LED Technology Opens New Horizons for Smart Lighting Applications The evolution of Multi-Pixel LED technology has initiated a giant leap in the development of intelligent lighting systems which are most visible in the automotive industry. Now the first hybrid LED provides smart headlights with more than 1000 individually controllable pixels. Ralph Bertram, who is working on advanced LED device concepts, and Norbert Harendt, who is developing optics solutions for general lighting at Osram Opto Semiconductors, show that automotive lighting is just one of the potential areas in which intelligent selective pixel control can be applied. Options for the use in general lighting, such as information display for outdoor, indoor, retail or industrial applications, are very versatile. Read more »

Resources | LpR Article | Research | Sustainability | Environment | Apr 27, 2018

Repro-Light - Looking for a Sustainable and Modular Luminaire Architecture

Repro-Light - Looking for a Sustainable and Modular Luminaire Architecture The Repro-light project aims to re-conceptualize the European lighting industry towards more sustainability and competitiveness in terms of production and time to market. This will be achieved through the implementation of modular luminaire architecture and a smart production scheme, demonstrated by the development of a reconfigurable customized LED luminaire designed to improve the customers’ health. Read more »

Resources | LpR Article | Research | Optics | Engineering | Apr 13, 2018

Optimization of Freeform Optics Using T-Splines in LED Illumination Design

Optimization of Freeform Optics Using T-Splines in LED Illumination Design Freeform optics is the game changer in the illumination industry in terms of its ability to redirect the light into the target area. Non-Uniform Rational B-splines, commonly known as NURBS are widely used to represent freeform curves and surfaces. There are certain optical systems where local modification of the surface is necessary during the design or optimization phase. In such cases, NURBS cannot offer such transformations. But a new mathematical representation called T-splines make this feasible. Though its potentiality is well described, this has not been implemented in any optimization routine so far. Annie Shalom Isaac, Jiayi Long and Cornelius Neumann from the Karlsruhe Institute of Technology demonstrate the advantage of the local refinement ability of T-splines by implementing it in the optimization routine and the results are evaluated. Results show that T-splines provide more uniform and homogenous light distribution as compared to NURBS at a faster convergence rate. This makes optical design or optimization using T-splines an intuitive approach for future freeform design tasks. Read more »

Resources | LpR Article | Environment | Mar 27, 2018

A World of LED Lights - The Cost of Waiting

A World of LED Lights - The Cost of Waiting Today, LEDs dominate the lighting domain. They are efficient and manufacturers understand how to implement them for different lighting applications. While energy efficiency is rather well understood, the impact of the adoption speed is rarely discussed is. Benoit Bataillou, guest author from Pi Lighting, will have a look at the environmental cost of LED production versus the significant energy savings that a full transition to LEDs would bring. In a fictive scenario, he assumes that a transition takes place in a heartbeat today and compares that with the usually supposed scenario of a full transition to LED lights in 2025. Read more »

Resources | LpR Article | Quality | Optics | Mar 13, 2018

Glare Reduction Made Easy

Glare Reduction Made Easy A pleasant lighting atmosphere due to low glare at the workstation is not only pleasant and performance-enhancing, but also legally required according to EU standard EN 12464-1. But what does “glaring” mean here? Dr. Claudius Noack, Technical Director at NORKA Leuchten, explains if luminaires with the same luminous flux are glaring to the same degree and if the same luminaires are glaring to the same degree at different workstations. He answers the questions of what a manufacturer does and if manufacturers are lying to themselves and therefore to their customers when providing information on the glare rating. Read more »

Resources | LpR Article | Technologies | Light Generation | Tunable White Light | Feb 28, 2018

A New Technology Is Changing the Tunable White Solutions

A New Technology Is Changing the Tunable White Solutions Tunable white LEDs are one key element of human centric lighting. Until today, different solutions are currently available but none of them is easy to apply or cost effective enough to speed up the diffusion of human centric lights in building projects. A new approach for tunable white solutions is able to provide flexible lighting for multiple occasions without sacrificing output or going over project budget. Phil Lee, Senior Lighting Engineer from Meteor Lighting will compare this new technology, called ColorFlip™, to conventional tunable white solutions, and talk about current tunable white issues. Read more »

Resources | LpR Article | Tech-Talks Bregenz | Quantum Dots | Feb 27, 2018

Tech-Talks BREGENZ - Ken T. Shimizu, Research & Development Director, Lumileds

Tech-Talks BREGENZ - Ken T. Shimizu, Research & Development Director, Lumileds QDs have been a hot topic in lighting for a while already, but up until now they haven’t been adopted on a large scale in lighting. The adoption began in display devices because some of the technical issues were of less concern in this application. With continuing development, QDs are now also becoming interesting for general lighting applications. Ken Shimizu, Director of Novel Technologies and Devices, Research and Development at Lumileds, attended the LpS in Bregenz and made a presentation about the company’s QD technology. In this interview he gives some background information about the QD program and future steps. Read more »

Resources | LpR Article | Commentary | Trends | Feb 21, 2018

Can You Show Me the Next S-Curve, Please?

Can You Show Me the Next S-Curve, Please? The evolution of technologies is often described using the “S-curve” model. In the early stage, in the first phase of its life cycle, technology is mainly driven by fundamental research. Only a few players are active at that time and innovation steps are quite large. In the second phase, early adopters start to develop products and bring them to market. This phase is characterized by huge investments. In the third phase, more and more players enter the technology field, competition becomes important and development speed of the technology decreases. In the last phase, the technology is mature, (nearly) everybody can use it, there are fewer margins and the technology should be replaced by a new one. Many of the SSL technologies have meanwhile reached maturity. Where are the upcoming technologies, what will be the next S-curve? Looking at technology discussions and lectures at LpS 2017 I tried to find answers to these questions. Read more »

Resources | LpR Article | Technologies | LiFi | Jan 15, 2018

LiFi - What It Is, How It Works, What It Provides, How to Apply, and Its Future Prospects

LiFi - What It Is, How It Works, What It Provides, How to Apply, and Its Future Prospects The acronym LiFi (Light Fidelity) was born at the beginning of the 2010s. Its name derives from the very well-known WiFi (Wireless Fidelity). The term VLC (Visible Light Communication) is used in the restricted instances of visible light. Mr. Luc Chassage who works for Oledcomm and the Versailles University is also Scientific Committee President of the Global LiFi Congress that offers 20 lectures dealing with all aspects of LiFi. He is a profound expert in this technology field. Mr. Chassage explains the functionality, pitfalls and hurdles to overcome, the disadvantages and advantages, and best practice to apply LiFi. Read more »

Resources | LpR Article | Research | Thermal Management | Jan 15, 2018

Thermal Issues Posed by Compact Packaging and IoT for Next Generation SSL

Thermal Issues Posed by Compact Packaging and IoT for Next Generation SSL Besides general lighting, LEDs are penetrating many areas. At the same time, Internet of Things (IoT) has been rapidly evolving. Added electronics are expected to add an additional 70% to overall heat generation. Therefore, solving thermal problems will become more important again; on a par with footprint area and cost. Prof. Mehmet Arik, Director of EVATEG Center for Energy Efficient Electronics and Lighting Technologies at the Ozyegin University, and Umut Zeynep Uras, master student at the Ozyegin University, present some of the current, local, hotspot thermal issues caused by tight packaging. The severity of the problem for future lighting systems with added IoT will also be discussed. Finally, possible technologies to meet those challenges will be shown. Read more »

Resources | LpR Article | Research | Light Generation | Jan 01, 2018

Hybrid Quantum Dot Light Emitting Electrochemical Cells

Hybrid Quantum Dot Light Emitting Electrochemical Cells Several new light generation technologies that are overshadowed by LEDs and OLEDs are investigated. Most of these technologies are in a very early stage of research. One such technology, the LEC technology, was presented at LpS 2017. Light emitting electrochemical cells can be compared to OLEDs, but they are based on a much simpler inorganic architecture. The innovation in the presented approach lies in the combination with quantum dots, resulting in a hybrid solution. This novel attempt with all its consequences and future prospects was the reason that the LpS Scientific Award jury voted to bestow the award on Dr. Ekaterina Nannen, Group Leader of the Research Group „Solid State Lighting“ at the Nano-Energie-Technik- Zentrum (NETZ) of the University Duisburg-Essen and her research team, Julia Frohleiks and Svenja Wepfer. Read more »

FEATURED

WHITE PAPER - How to Overcome the Security Challenges of Smart Lighting

WHITE PAPER - How to Overcome the Security Challenges of Smart Lighting IoT-powered lighting systems are backbones for smart building applications such as energy harvesting, space optimization, and predictive maintenance. Read more »

FEATURED

Smart High-Power LED Driver from Lifud

Smart High-Power LED Driver from Lifud As a pioneer in the LED industry who dared to break away from conventions and apply non-isolated design to the LED driver for UFO high bay driver, Lifud has done a good job referring to the sales records and customer feedback of the LF-FHBxxxYx series. Read more »

EDITORIAL

High Conductive Foils Enabling Large Area Lighting

High Conductive Foils Enabling Large Area Lighting Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP as one of the leading partners for research and development for surface technologies and organic electronics and Sefar AG, a leading manufacturer of precision fabrics from monofilaments, developed a roll-to-roll ... Read more »

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