LpR Article | Technologies | Jun 28, 2016

OLED Technology in Lighting Applications

Prototypes and niche applications with OLEDs for lighting have been demonstrated over the past few years. Now there are indications that OLED technology is ready for mass production or at least will be ready very soon. Franco Musiari, Technology Specialist at ASSODEL analyzed the current status and future perspectives of OLED technology. Read more »

LpR Article | Technologies | Jun 28, 2016

LED and Lens Degradation Through Volatile Organic Compounds

In general, LEDs are very resistant light sources. Nevertheless, glues, conformal coatings, o-rings, gaskets, and potting compounds, all materials that are frequently used in the construction of LED based luminaires or lamps and often contain volatile organic compounds (VOCs) may have a negative impact on performance, reliability and lifetime. Edward Steinke, application engineer at Cree, explains the set of problems and how to prevent these issues based on Cree’s products, using their test kit components, as well as components for lamp and luminaire applications. Read more »

LpR Article | Technologies | Jun 28, 2016

Reliability Oriented Design of LED-Based Light Sources

The transition from traditional light sources to SSL systems requires a different design philosophy to achieve the advantages offered by LED light sources. The key approach is based on the parallel design of thermal, electrical, optical and spectral properties of the light source. Matteo Meneghini, Gaudenzio Meneghesso, Enrico Zanoni and Matteo Dal Lago from the Department of Information Engineering at the University of Padova, and Nicola Trivellin from LightCube SRL explain this approach including the importance of the electrical management of LEDs, comparing modulation techniques to constant current, differentiating between versatility and efficiency. Read more »

Technologies | LEDs | Light Conversion | Jun 23, 2016

New Phosphor Promises Cheaper and more Efficient Next-Generation LED Lighting

Researchers from KU Leuven (Belgium), the University of Strasbourg, and CNRS have discovered a new phosphor that could make next-generation fluorescent and LED lighting even cheaper and more efficient. The team used highly luminescent clusters of silver atoms and the porous framework of minerals known as zeolites. Read more »

Technologies | LEDs | Laser | Light Conversion | LiFi | Jun 23, 2016

Perovskite Phosphor Provides High Quality White Light and Boosts VLC

Mark Peplow recently reported on the Chemical & Engineering News website about the latest encouraging research results from a research team from CEMSE and KAUST. The researchers found that combination of solution-processed CsPbBr3 perovskite nanocrystals (NCs) with a conventional red phosphor produces high quality white light when pumped with a blue LED or laser. Furthermore excited-state lifetime is short enough to provide record-breaking high bandwidth for visible light communication (VLC), aka LiFi. Read more »

LpR Article | Technologies | Jun 21, 2016

Safety Issues for LED Drivers with PWM Operation Modes by Product Approvals Ltd.

In many cases LED drivers manage their output power with PWM controlled switched mode power supply-topologies. The output voltages are filtered and normally DC voltages with low ripple apply at the output connectors of LED drivers. During dimming these circuits can behave very differently and therefore safety issues may arise. Siegfried Luger, CEO at Luger Research e.U. and John Showell, Product Safety Consultant at Product Approvals Ltd. have a closer look at those operation modes and the requirements on voltage limits. Read more »

LpR Article | Technologies | Jun 21, 2016

Optimization of SSL LED Devices by Osram Opto Semiconductors

There are different levers to improve LED performance. Ralph Bertram, application engineer for SSL products, and Alexander Wilm, key expert in the SSL application engineering department at Osram Opto Semiconductors, have a look into the device itself and explore the principal limitations of the different contributors to device efficacy. They show how to balance driving current and chip size to define the right LED, and explain the impact on performance and system costs of LED packages for the intended lighting task approaches for lighting strategies. Read more »

LpR Article | Technologies | Jun 20, 2016

LED Light Spectrum Enhancement with Transparent Pigmented Glazes

While LED bulbs have the distinct economic advantages of using less energy, producing less heat and lasting years longer than traditional incandescent bulbs, when objects are viewed under LED light, they frequently appear to be of different colors than when viewed in sunlight or with incandescent lights. Jan-Marie A Spanard from Light Spectrum Glazes proposes and explains an approach to optimize the spectral distribution of LED light to overcome this weakness. Read more »

LpR Article | Technologies | Jun 20, 2016

High Color-Rendering, Full-Visible-Spectrum LEDs by Soraa

The first wave of conventional white LEDs primarily focused on lumens per Watt. These LEDs were based on phosphor down-conversion using primary blue “pump” emission. Currently LEDs are catching up in regards to light quality using different approaches. Aurelien David, Senior Principal Scientist and Mike Krames, Chief Technology Officer at Soraa explain their technology approach of violet-pumped, full-visible-spectrum LEDs, and the interrelated challenges and advantages. Read more »

LpR Article | Technologies | Jun 08, 2016

InGaN Nanowires Make Light Mixing Efficient and Smart

The correlated color temperature (CCT) of high color rendering index (CRI) LED lighting systems can, in principle, be tuned over a wide range. As an alternative approach to conventional phosphor based LEDs, a full-color LED array consisting of red, green and blue (RGB) InGaN based nanowire LEDs monolithically integrated on a micro-scale level has been proposed and fabricated. J. Lee from the Nano Electronics Lab at the Samsung Advanced Institute of Technology, Renjie Wang, Hieu P. T. Nguyen, Ashfiqua T. Connie, Ishiang Shih, and Zetian Mi from the Department of Electrical and Computer Engineering at McGill University in Montreal explain how this technology works and how the three multi-color subpixels on the same chip can be separately biased and can exhibit full-color emission which can be tuned controllably in a wide CCT range. Read more »

LpR Article | Technologies | Jun 08, 2016

Mastering Thermal Issues in LED PCB Design & Laminate Selection by Ventec Europe

LED applications are not the only applications that are driving the need for thermal issues to be considered and mastered in PCB design, but they are certainly amongst the most challenging. Designing LED PCBs requires many considerations and key are those that arise from multiple heat sources in close proximity. Martin Cotton, Director OEM Technology of Ventec Europe describes the process and criteria used when designing PCBs (Printed Circuit Boards) for use in LED applications using thermally conductive IMS (Insulated Metal Substrates). He goes into technical detail with charts and diagrams that explain everything the designer would need to consider when selecting a laminate and commencing a design. Read more »

LpR Article | Technologies | Jun 07, 2016

New Class of Siloxane Polymers for Advanced LED Packaging

Packaging presents a major challenge to further improve LED device efficiency and reliability. A novel class of high stability siloxanes forms a technology platform to address such opportunities in die attach, encapsulation, and light outcoupling applications. Dr. Juha Rantala, CEO & Founder, Dr. Joerg Rockenberger, Director Application & Business Development, Dr. Jyri Paulasaari, Vice President Technology, Dr. Jarkko Heikkinen, Director Inks & Pastes. Markus Laukkanen, Application Manager, and Dr. Janne Kylmä, Vice President Engineering & Production at Inkron Oy explain the material properties and give examples of how these new materials in combination with novel nanomaterials enable products fully compatible with current process tools and flows while having superior properties. Read more »

LpR Article | Technologies | Jun 03, 2016

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 »

Resources | Fundings | EU-Calls | Technologies

EU Call: FET-Open Research and Innovation Actions

This call is open for any kind of research on future and emerging technologies (FET) in early stages. Proposals should cover high-risk, interdisciplinary research on radically new technologies. Read more »

LpR Article | Technologies | May 24, 2016

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 | Technologies | May 19, 2016

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 »

Technologies | OLEDs | Light Conversion | May 13, 2016

Research on OLEDs with Ultrathin Emissive Layers and a Spacer-Free Structure

Since C.W Tang demonstrated the first organic light-emitting diodes (OLEDs) based on a double-layer structure of organic materials in 1987, flat-panel displays and lighting applications based on OLED technology have grown dramatically because of their attractive features such as ultra-thin structure, light-weight and flexibility. To achieve a desirable OLED performance, a host-dopant system is adopted. This not only leads to an increase in material cost and device processing time, but also makes it difficult to control dopant concentration accurately. Therefore, OLEDs with dopant-free and ultrathin emissive layers (UEMLs) have aroused much attention. Shengfan Wu, Sihua Li, Qi Sun, Chenchao Huang & Man-Keung Fung recently published the results of their research on such ultrathin emissive layers (UEMLs) of phosphorescent materials for OLED applications. Read more »

Technologies | Smart Lighting + IoT | Apr 05, 2016

The “Internet of Light” – the Key to the “Internet of Things”

The Internet of Things is the next industrial revolution. As a specialist for innovative lighting components and systems, Tridonic is convinced that lighting will play a decisive role in the Internet of Things (IoT). Therefore, Tridonic developed the toolbox net4more which will not only connect luminaires with each other, but deliver an added value that goes far beyond lighting. Where do we stand today? Read more »

Technologies | LEDs | White LEDs | Feb 25, 2016

Cree Announces Outstanding R&D LED Efficacy Combined with Superior Color Quality

Cree, Inc. records another LED industry first with the demonstration of a single high-power LED delivering nearly 1,600 lumens at 134 lumens-per-watt (LPW) with similar color quality as an incandescent light bulb. With this result, Cree achieved a breakthrough 25 percent increase in lumens per watt (LPW) over production LEDs of similar color quality under operating conditions found in real-world LED lighting applications. This important milestone coupled with Cree’s latest SC5 Technology™ platform will lead to LED systems with increased performance, lower cost and better light. Read more »

Technologies | Smart Lighting + IoT | LiFi | Feb 10, 2016

Apple Experimenting with Ultra Fast Light-Based Li-Fi Wireless Data for Future iPhones

Recent versions of iOS have been found to contain references to Li-Fi, an experimental high-speed wireless networking protocol that uses pulses of light to transmit data and is being marketed as a long-term replacement for Wi-Fi. Read more »

Technologies | LEDs | GaN-on-Si | Jan 18, 2016

Plessey Builds LEDs in Cubic GaN on 3C-SiC/Si To Overcome The Green Gap

Plessey, Anvil Semiconductors and the University of Cambridge announced today that they are working together to fabricate high efficiency LEDs in cubic GaN grown on Anvil's 3C-SiC / Si substrates. Cubic GaN has the potential to overcome the problems caused in conventional LEDs by the strong internal electric fields which impair carrier recombination and contribute to efficiency droop. This is particularly true for green LEDs where the internal electric fields are stronger and are believed to cause a rapid reduction in efficiency at green wavelengths known as "the green gap". The availability of cubic GaN from a readily commercialisable process on large diameter silicon wafers is as a key enabler for increasing the efficiency of green LEDs and reducing the cost of LED lighting. Read more »

Technologies | LEDs | Material Science | Jan 13, 2016

Uncovering Oxygen’s Role in Enhancing Red Eu-Doped GaN LEDs

Oxygen is indispensable to animal and plant life, but its presence in the wrong places can feed a fire and cause iron to rust. In the fabrication of solid state lighting devices, scientists are learning, oxygen also plays a two-edged role. While oxygen can impede the effectiveness of gallium nitride (GaN), an enabling material for LEDs, small amounts of oxygen in some cases are needed to enhance the devices’ optical properties. GaN doped with europium (Eu), which could provide the red color in LEDs and other displays, is one such case. Read more »

Technologies | Light Generation | Jan 12, 2016

Innovation Could Revive Incandescent Lighting, Bring More Efficient Solar Cells

Incandescent lighting could make a comeback with a new type of filter that "recycles" infrared photons and improves efficiency, an innovation that also could enable solar cells to convert heat into electricity more efficiently than conventional photovoltaic technology. Read more »

Technologies | Research | Light Generation | Health | Perception | Simulation Tools | Jan 04, 2016

Latest Research Publications in the Journal of Solid State Lighting

On December 24th and 29th, 2015, three new articles have been published in the SpringerOpen Journal of Solid State Lighting. The three articles are titled "Optical Role of Die Attach Adhesive for White LED Emitters: Light Output Enhancement without Chip-Level Reflectors", "The Importance of Intrinsically Photosensitive Retinal Ganglion Cells and Implications for Lighting Design", and "Towards Perceptual Accuracy in 3D Visualizations of Illuminated Indoor Environments". Read more »

Technologies | Luminaires | Outdoor Applications | Nov 26, 2015

Gunshot Detection for Lighting Fixtures

Cities and their emergency responders will soon have a new way to deploy gunshot detection technology and be able to respond to incidents and react faster to protect their residents. A memorandum of understanding (MOU) between GE Lighting and SST, Inc., developer of the ShotSpotter™ crime detection and location suite, lays ground to embedding sophisticated ShotSpotter technology into GE’s intelligent LED street lights. Read more »

Technologies | Light Conversion | Quantum Dots | Nov 25, 2015

Cadmium-Free Quantum Dot Technology in LED Lighting

Nanoco and its partner Marl International, a pioneer of the LED lighting industry, demonstrated four product lines based on Nanoco’s CFQD® quantum dot film technology last week at LuxLive. The CFQD® Quantum Dot technology as a revolutionary solution for high-end lighting applications in retail and specialty, architecture, and agriculture, where maintaining true-to-life color representations maximizes user experience and value. Read more »

Technologies | Electronics | Oct 06, 2015

µModule LED Driver Integrates All Circuitry, Including the Inductor in a Surface Mount Package

David Ng, Module Development Manager at Linear Technolgies, explaines the features of a compact step down DC/DC module for distributed LED power supplies in a DC grid that offers high efficiency, a wide dimming range, and a current range from 35 mA to 1 A. Read more »

Technologies | LEDs | Light Conversion | Sep 01, 2015

FAU Researchers Create the World's First White LEDs Based on Fluorescent Proteins

LEDs are up to 80 percent more energy-efficient than normal light bulbs and last around five times as long as energy-saving light bulbs. As a result they are being used more and more frequently as a source of light. Nevertheless, white LEDs still have room for improvement, as current manufacturing processes are either very expensive or result in the lifetime of the LEDs being reduced. Researchers at FAU have now developed a new, rather unusual manufacturing method: their LEDs are partly made of fluorescent proteins. Read more »

Technologies | LpR Article

Solving the Phase-Cut Dimming Challenge

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 »

Technologies | LpR Article

Street Lighting Evolution through LED Technology

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 »