LED professional Review (LpR) - Articles

LpR Article | Jun 21, 2016

Managing Manufacturing and Supply Chain Challenges in LED Luminaire Design by Sanmina

Managing Manufacturing and Supply Chain Challenges in LED Luminaire Design by Sanmina Today’s luminaires are often complicated lighting systems and have a wide range of applications from in-home luminaires and retail to very high power outdoor lighting. This causes several challenges in both design and manufacturing. Some of these problems may have already been solved by design and manufacturing firms having expertise with LED luminaire design and manufacturing. Gelston Howell, Senior Vice President at Sanmina explains how to manage some of these design, manufacturing and supply chain challenges by using examples. Read more »

LpR Article | Jun 20, 2016

Cost Saving Potential with Automation and Well Designed Processes by BJB GmbH

Cost Saving Potential with Automation and Well Designed Processes by BJB GmbH The manufacturing of modern LED luminaires and conventional fixtures has some similarities as well as some distinct differences that result in added challenges. Automation, in combination with a well-conceived product design and process combined with well-matched components, allows for economical manufacturing without compromising production quality and, consequently, reliable, high performance, and high quality luminaires. Olaf Baumeister, Head of Product Development and BJB-Automation at BJB GmbH, explains and discusses technical challenges, successful concepts and solutions. Read more »

LpR Article | Research | Jun 20, 2016

Luminescent Glasses and Glass Ceramics for White Light Emitting Diodes by the Fraunhofer Institute and the South Westphalia University of Applied Science

Luminescent Glasses and Glass Ceramics for White Light Emitting Diodes by the Fraunhofer Institute and the South Westphalia University of Applied Science Luminescent glasses or glass ceramics represent an interesting alternative to LED phosphor due to their high thermal and chemical stability. A series of rare-earth doped glasses are investigated for their potential application as photon converters for solid-state lighting applications. Franziska Steudel, Sebastian Loos, Bernd Ahrens, and Stefan Schweizer from the Fraunhofer Institute and the South Westphalia University of Applied Science respectively, show that the color coordinate of double-doped glass can be varied over a broad spectral range by changing the rare-earth doping ratio accordingly. In addition, double-doping allows for a change in the color coordinate by using different excitation wavelengths. Read more »

LpR Article | Technologies | Jun 13, 2016

Cost and Performance Optimization of Thermal Management Solution for High Power LEDs by Cambridge Nanotherm

Cost and Performance Optimization of Thermal Management Solution for High Power LEDs by Cambridge Nanotherm The LED industry has a challenge. General lighting requires very bright LEDs that can replace incandescent and halogen lights. Manufacturers need efficacy, cost and manufacturability to be “just right” but most leading solutions, especially in thermal management, are short of the mark. Giles Humpston, applications engineer, Cambridge Nanotherm, discusses ways to combine performance with reasonable costs and good manufacturability. Read more »

LpR Article | Jun 10, 2016

Potting Processes as a Part of LED-Based Lighting Module Manufacturing Methods by ViscoTec Pumpen and Dosiertechnik GmbH

Potting Processes as a Part of LED-Based Lighting Module Manufacturing Methods by ViscoTec Pumpen and Dosiertechnik GmbH Many manufacturing processes need very accurate dosing. One such dosing process concerns the potting of LED-modules. Numerous parameters affect the potting quality. Willi Huber from the Business Unit Adhesives & Chemicals at ViscoTec Pumpen- u. Dosiertechnik GmbH explains casting equipment, critical parameters and appropriate potting methods. Read more »

LpR Article | Jun 06, 2016

Power over Ethernet Lighting for Commercial Buildings by Molex

Power over Ethernet Lighting for Commercial Buildings by Molex Today, information technology (IT) and lighting are separate worlds. It is necessary to create a bridge between these worlds, not only from a technical standpoint but also from the perspective of understanding what is important to each industry. Giovanni Frezza, Group Product Manager at Molex, discusses how LEDs and PoE may pave the way with new power standards: LEDs far outperform the lumens output of older lighting technologies. Today, the PoE standard for LED is 30 W. An UPOE standard for 60 W is in the works, and an expansion called BP is in progress for up to 95 W. Read more »

LpR Article | Research | Jun 03, 2016

Thin-Film Light Management System for Intelligent Large-Area LED Luminaires by the Centre Suisse d’Electronique et de Microtechnique SA

Thin-Film Light Management System for Intelligent Large-Area LED Luminaires by the Centre Suisse d’Electronique et de Microtechnique SA The recent advances in Solid State Lighting have triggered the development of smart lighting solutions. However, the point-like nature of LEDs imposes the use of inefficient and/or bulky light scattering sheets or costly, short-pitch LED arrays to achieve acceptable spatial luminance uniformity. Ph.D. Oscar Fernandez, Senior R&D Engineer at the Centre Suisse d’Electronique et de Microtechnique SA (CSEM) shows a new approach in the form of an innovative thin form-factor light management (LM) system comprising a highly engineered combination of thin-film diffractive nano-optical and refractive micro-optical elements. Read more »

Resources | LpR Article | Event-Reports | Trends | Jun 02, 2016

Light + Building Post Show Report: The Six Most Noteworthy Observations by LED professional

Light + Building Post Show Report: The Six Most Noteworthy Observations by LED professional In the weeks and months before the show it was obvious that the major topics were going to be IoT and connectivity. There are many reasons for this. One is that LED lighting has become established but the big deals for smart lighting and human centric lighting are missing. IoT seems to be the way to improve communication and enable both smart lighting and HCL. Arno Grabher-Meyer from LED professional gives a summary of his impressions of the fair in regards to these topics, and beyond. Read more »

LpR Article | May 30, 2016

The Value of Dark Skies - About Environmentally Friendly Lighting by the International Dark-Sky Association (IDA)

The Value of Dark Skies - About Environmentally Friendly Lighting by the International Dark-Sky Association (IDA) For many years no one worried about light pollution: on the contrary, the brighter the better. Then it became evident that darkness also has its value. J. Scott Feierabend, executive director of the International Dark-Sky Association (IDA), presents and explains in detail, the latest findings and suggestions published in the “New IDA LED Lighting Practical Guide” and “New IDA Standards on Blue Light at Night”. He also discusses how to illuminate public areas while avoiding excess light pollution. Read more »

LpR Article | Technologies | May 27, 2016

Create Colorful and Bright LED Light with an LED Matrix Dimmer by Linear Technology

Create Colorful and Bright LED Light with an LED Matrix Dimmer by Linear Technology RGB LEDs are quite common and used in many applications today. More advanced multi-color solutions like RGBW, RGBA or RGBWA offer huge advantages over RGB solutions, but several aspects are more complicated. Keith Szolusha, applications engineering section leader for power products at Linear Technology explains the advantages of RGBW systems, how they work, how to set up such systems, and how to drive them correctly using Linear Technology’s LT3965 8-switch LED matrix dimmer in combination with the LT3952 boost-buck LED driver as an example. Read more »

LpR Article | May 24, 2016

Safety Concept for LED Street Lighting by Phoenix Contact

Safety Concept for LED Street Lighting by Phoenix Contact Street and building lighting has profited greatly from the advantages of LED technology. While modern LED lampposts have dielectric strengths of up to 6 kV, surge currents and voltages occurring in the grid can be significantly higher. Andreas Schamber, Product Manager for surge protection at Phoenix Contact, presents and discusses a comprehensive power surge protection concept to prevent blackouts during power surges and to protect investments in LED lighting based on the company’s product portfolio. Read more »

LpR Article | Technologies | May 19, 2016

3-Pad LED Flip Chip COB by Flip Chip Opto

3-Pad LED Flip Chip COB by Flip Chip Opto Wafer level packaging and flip chip design are the most recent trends in LED manufacturing and packaging. These LED types are perfectly suited for producing COB modules. This combination already promises better thermal performance than standard SMD package based products. However, there is still room for improvements. Pao Chen, Director of Research and Development at Flip Chip Opto shows how a 3-pad flip chip LED further reduces thermal resistance, allows higher power and can help to reduce costs. Read more »

LpR Article | Research | May 17, 2016

Human-Focused Outdoor Illumination: Trade-Off Between Pleasing Color and Circadian Action, by the Vilnius University

Human-Focused Outdoor Illumination: Trade-Off Between Pleasing Color and Circadian Action, by the Vilnius University A smart RGBA solid-state light engine with tunable correlated color temperature (CCT) and high-fidelity color rendition was applied for the validation of the Kruithof hypothesis in several outdoor environments. Subjects were asked to find the most “pleasing” illumination conditions by performing a CCT adjustment. Maintaining constant illuminance, the mean selected CCT was found to increase from about 3000±200 K at 5 lx to about 3500±250 K at 50 lx almost independently of the content of the viewed scene. Dr. Pranciškus Vitta, Head of Lighting and Electronics System Lab at the Vilnius University shows that this increase is statistically significant and provides qualitative validation of the Kruithof hypothesis in outdoor environments, but with the intervals of CCT for “pleasing” illumination, it is substantially broader and shifted to higher values. Read more »

LpR Article | May 11, 2016

230 VAC Driven LED Modules with Strongly Reduced Flicker, by euroLighting

Fact Box One of the continuing trends in LED lighting is toward AC driven LED modules. Big progress has been made regarding dimmability and reduction of flicker. However, there are still differences in the various concepts that lead to very different results. Wolfgang Endrich, founder and managing director of euroLighting presents a recently improved new concept to significantly reduce flicker. Read more »

LpR Article | May 09, 2016

White Hybrid Light-Emitting Diodes: A Plausible Solution for Commercialization and Health Issues, by the University of Erlangen-Nuremberg (FAU)

White Hybrid Light-Emitting Diodes: A Plausible Solution for Commercialization and Health Issues, by the University of Erlangen-Nuremberg (FAU) One of the challenges in terms of commercialization of white LEDs is the need for cheap, inorganic phosphors. In this context, hybrid LEDs have recently emerged as a new approach based on downconverting organic coatings. The authors, Pedro B. Coto from the Institute for Theoretical Physics, Marlene Pröschel and Uwe Sonnewald from the Department of Biology, and Lukas Niklaus, Michael D. Weber and Rubén D. Costa from the Department of Chemistry and Pharmacy at the University of Erlangen-Nuremberg (FAU), describe this technology and cover recent breakthroughs and their prospects. Read more »

LpR Article | May 06, 2016

Lighting with LEDs – More than just Illuminating Objects, by Bartenbach Lichtlabor

Lighting with LEDs – More than just Illuminating Objects, by Bartenbach Lichtlabor Light is more than just vision. It includes aspects of well-being, health and emotions. Dr. Wilfried Pohl, Markus Canazei and Christian Knoflach from Bartenbach report on their experiences and discuss the requirements for LED lighting. They also write about physiological effects and make recommendations for improvements. Read more »

LpR Article | Apr 21, 2016

Advanced Bluetooth 4.0+ Based Smart Lighting Technology

Advanced Bluetooth 4.0+ Based Smart Lighting Technology Smart lighting and lighting controls are not restricted by hardware or traditional lighting control protocols anymore. Today, system modifications and firmware updates can all be done over-the-air. Wireless technologies enable lighting controls in places where it was not an option before. Besides Bluetooth, Zigbee and WiFi there are proprietary technologies in use. Saara Guastella M.Sc. in Lighting Engineering and Lighting Controls, is Product Marketing Manager at Casambi. In the following article she introduces Casambi’s technology based on Bluetooth Low Energy, and describes, explains and compares it with other established communication technologies for smart lighting. Read more »

LpR Article

3-Pad LED Flip Chip COB

3-Pad LED Flip Chip COB Wafer level packaging and flip chip design are the most recent trends in LED manufacturing and packaging. These LED types are perfectly suited for producing COB modules. This combination already promises better thermal performance than standard SMD package based products. However, there is still room for improvements. Pao Chen, Director of Research and Development at Flip Chip Opto shows how a 3-pad flip chip LED further reduces thermal resistance, allows higher power and can help to reduce costs. Read more »

Technologies | LpR Article

Solving the Phase-Cut Dimming Challenge

(a) Analog controlled LED dimming. (b) Digital controlled LED dimming. (c) DimMasterTM controlled LED dimming The evolution of dimmable LED lighting is an ongoing subject and phase-cut dimming is often dissatisfactory. While some weaknesses may be acceptable in residential applications, they are definitely not acceptable in professional applications. Stage lighting, studio lighting, TV and movie lighting set the highest standards. Craig Sharp and Bill Trzyna, Research & Design Engineers at CCI Power Supplies LLC discuss which developments helped to overcome limiting obstacles and led to a solution that also satisfies stringent requirements. Read more »

Trends | LpR Article

Making Light Work – Light Sources for Modern Lighting Requirements

Flexible OLEDs are a technology lighting manufacturers and lighting designers are hoping will mature Solid state light sources are the core of modern lighting installations. To get in the right mood for the IYL 2015, Dr. James Gourlay, Chief Technology Officer with Design LED Products, looks at the ways to make LED lighting more efficient, satisfy user demands and to bring SSL design to the next evolutionary level. Read more »

Trends | LpR Article

LEDs are Revolutionizing Light – The Past and Future of Lighting

Experts agree that intelligent lighting modules like this Xicato XIM module that offers additional features and which can be integrated in the IoT will soon be an integral part of our technical lives Light is a basic part of life as such and modern living relies on artificial light. Lighting is a constantly developing, even accelerating technology, with LEDs representing the current zenith. On the occasion of the beginning of the IYL 2015, Stephan Wegstein representing VESTEL, a leading contract manufacturer in Turkey, has been asked to explain the challenges this poses and how suitable strategies and technologies can assist in staying on top of developments. Read more »

Quality | LpR Article

Guidance on Specifying Solid State Lighting Luminaires

The CIE x/y color space with the Planckian locus and CCT values Certification marks of renowned test institutes are useful tools for end users to easily estimate the quality of a product. They are also a good marketing tool for manufacturers to generate user trust and confidence in a product or the brand. The authors, Jaap Nuesink and Michael Schoof from DEKRA Certification B.V. explain what is needed and which parameters have to be covered in order to be certified, ending up in a guideline of how to qualify for the DEKRA Solid State Lighting Certification Mark. Read more »

Technologies | LpR Article

Street Lighting Evolution through LED Technology

SMI technologies with astronomical response has automatic changeover to lower light levels Standard electronics is usually based on a relatively simple straight-forward technology. Outdoor lighting is more challenging in several aspects, especially robustness. This is also true for the electronics. Sandra Solán, R & D Manager from ELT Electronic Division has studied this technology in depth. To celebrate the IYL 2015 she will explain technical advances, benefits, strengths and technical challenges of current and future street lighting systems for an electronics manufacturer. Read more »

Technologies | LpR Article

A New Approach to the Design of Driverless AC LED Light Engines

Example of a sub 5 W driverless LED light engine Driverless AC LED light engines have now become a commonplace item of commerce in the lighting industry. Nearly all of them use high voltage integrated circuit switching chips to intelligently change the number of LEDs in a string during a power line cycle so that the voltage of the LED string matches the instantaneous power line voltage. However, customers are demanding higher efficiency, lower cost, and especially a reduction in the flicker content of the emitted light. Peter W. Shackle, president of the consulting company, Photalume, describes some new circuits for AC LED light engines [1] that provide a non-dimming solution with reduced cost, increased efficiency and better light quality as perceived by the human eye. Read more »

Research | LpR Article

LED Office Lighting for Improved Well-Being and Performance

Study design The influence of artificial light in industry has been a topic of conversation for a while now but opportunities provided by LED lighting have made this subject even more important. Katrin Möller, Junior Researcher at the Competence Center Light, her research partners, Vincent Grote from the Human Research Institut, and Birthe Tralau from Zumtobel Lighting, investigated the effects of LED and fluorescent lamp lighting on human well-being and performance in an office environment, in a comparative laboratory study. Read more »

Leading Article | LpR Article

2015 Year of (LED) Light

While industry has largely concentrated on developing retrofit LED lamps that integrate into existing infrastructure, new applications are emerging that allow engineers, designers and industry to explore the potential of SSL technologies The advent of artificial lighting has revolutionized society. 2015, in particular, will go a long way in establishing solid-state light-based technologies as a vital area of innovation for the 21st century. Dr. Amrita Prasad from LED professional gives an overview of the technical evolution of (LED) lighting and how this may have triggered UNESCO’s decision to make 2015 the Year of Light. Read more »

Research | LpR Article

Direct Current (DC) Supply Grids for LED Lighting

Typical AC lamp driver Since many alternative energy sources as well as electronics and controls technologies are based on DC current, DC grids have been investigated more intensely in the last decade. DC grids with a centralized AC/DC conversion have proven to be advantageous in server farms. While LED lighting is also a DC current related technology, an obvious choice would be to use DC grids for them. Prof. Eberhard Waffenschmidt from the Cologne University of Applied Science in conjunction with Philips Research presents the results of an office building DC lamp system installation with photovoltaic (PV) support. Read more »

Research | LpR Article

A Self-Compensation Approach for Maintaining the Chromaticity Coordinates of Phosphor Converted LEDs Upon Temperature Variations

Line scans for the temperature profiles along the vertical direction of the LED package Solid-state light sources for general illumination applications are currently becoming more and more popular. Maintaining chromaticity coordinates over temperature is a challenge. Wolfgang Nemitz, Franz P. Wenzl, Susanne Schweitzer, Christian Sommer, Paul Hartmann from the Institute for Surface Technologies and Photonics at Joanneum Research, and Paul Fulmek and Johann Nicolics from the Institute of Sensor & Actuator Systems of the Vienna University of Technology investigated this issue and propose a promising new solution. Read more »

Resources | LpR Article | Tech-Talks Bregenz | Measurement | Jan 09, 2015

Tech-Talks BREGENZ - Prof. Jiangen Pan, Everfine, Founder & CTO

Prof. Jiangen Pan With ever-increasing demands on measurement equipment, it is becoming essential to meet user needs by providing combined solutions, which address optical, electrical and thermal issues. Prof. Jiangen Pan CEO, Founder and Chief Scientist at Everfine Institute of Optoelectronics, provided valuable insights on new compact solutions for LED measurements, his views and contributions towards global standards and how he works in his “thinking laboratory”. Read more »

Resources | LpR Article | Tech-Talks Bregenz | Market | SSL

Tech-Talks BREGENZ - Dietmar Zembrot, LightingEurope, President

Dietmar Zembrot Rapidly growing technologies and emerging market trends in solid-state lighting encourage new innovations largely driven by applications and technological developments. Dietmar Zembrot, President of LightingEurope and Managing Director of TRILUX Group, shared his insights on changing value chains and business models, Europe’s competitiveness and the main driving forces for current SSL technologies. Read more »

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