Articles & Interviews

Resources | Commentary | May 16, 2019

Well-Being, Light and Exhibition Lighting

Commentary from LpR 71: Well-being is the state of feeling healthy and happy, a good or satisfactory condition of existence, including the emotional and psychological sphere. In 1810, Goethe published a theory based on a human-based approach, combining visual appearance with harmony, culture, sensations and psychology. His color wheel was entitled "allegorical, symbolic, mystic use of color" and was composed of six hues, i.e. red (the beautiful), orange (the noble), yellow (the good), green (the useful), blue (the common) and violet (the unnecessary). The position on the wheel was harmonically relevant and in particular the colors in opposite position generated a strong psychological contrast and were called "opposite colors". Primary colors were yellow, blue and red, and the opposites were green, violet and orange, respectively. Goethe's wheel and the particular matching of opposites soon became popular and was used by the Impressionism movement, especially by Vincent van Gogh and Claude Monet. In this artistic movement, the special impact given by the combination of opposite colors were deliberately aimed to create special psychological effects and sensations. Read more »

Technologies | Smart Lighting + IoT | Resources | LpR Article | Jul 29, 2019

Voice Controlled Lighting that Protects Privacy and Data

LpR 71 Article - page 54: Intelligent lighting systems undoubtedly offer high comfort and energy efficiency. But especially conventional voice control systems like Amazon Alexa, Apple Siri or OK Google, with connected lamps and lighting fixtures are also becoming targets for uninvited guests. The benefits and technology of a new approach offering local voice control and artificial intelligence will be explained by Genia Shipova, Director Global Communications at Snips. Read more »

Medical | Tech-Talks Bregenz | Resources | Health + Environment | Jul 29, 2019

Tech-Talks BREGENZ - Dr. Octavio Perez, Adjunctant Researcher, Mt. Sinai Hospital

Dr. Perez received the LED professional Scientific Award 2018 for his paper on "Light and ED Clinical Wellness and Performance Improvement", which was published in LpR 70. The evaluation jury had the following to say about why they selected his paper: "The paper is based on the clear definition of the research question, hypothesis and objective of the research. The methodology of the screening study is described in detail and both subjective and objective parameters have been measured. Although Emergency Department lighting is a very special application, the paper provides interesting results." This interview provides background information on Octavio Perez, his work in general, his opinion on human centric lighting risks, opportunities and applications and how he became involved in this interesting research topic. Dr. Perez also provides additional details about the presented paper. Read more »

Flex LED Based Smart Light System for Healing of Chronic Wounds

LpR 71 Article - page 48: Chronic wounds are notoriously challenging to treat, because they do not follow the typical healing process or time-frame. The resulting burden is significant, affecting over 40 million patients. Blue light is known for its anti-microbial and anti-inflammatory effects in the initial stages of the healing process. David Kallweit, researcher at CSEM, reports about the joint development of a chronic wound treatment device with their MEDILIGHT partners, URGO RID, University of Heidelberg, SignalGenerix, Microsemi, Technical University of Berlin, and Amires. He furthermore shows how it works and discusses future prospects. Read more »

Circadian-Friendly Light Emitters: From CCT-Tuning to Blue-Free Technology

Common levels of blue radiation are sufficient to disrupt the circadian cycle, calling for blue-depleted emitters in the evening. Most current solutions employ low-CCT and suffer from poor light quality. Aurelien David, chief scientist at Soraa explains the melanopic lumen and its possible sources of inaccuracy related to the uncertainty in assessing the circadian action spectrum. In addition, he also discusses the concept of a blue-free emitter with minimal melanopic lumen at very low CCT and how such a spectrum providing a good light quality can be optimized. Read more »

Resources | Commentary | Aug 13, 2019

What the Heck Is Future Proof?

Commentary from LpR 72: The first time the question about future proofing LED systems came up seriously, was at LightFair 2018 when Siegfried Luger interviewed Patrick Durand. Since then, it has been the buzzword throughout the industry. Discussions concerning future proofing are often limited to wireless communications, IoT and some type of AI. But isn't there more? Read more »

Applications | Smart Lighting + IoT | Resources | LpR Article | Aug 13, 2019

Technologies for Shared Office Space

LpR 72 Article, page 66: Shared office spaces are gaining popularity as a flexible, resource-efficient and creativity-inspiring way to work. The dynamic nature of such office spaces requires building automation and lighting control solutions that can quickly be deployed and easily be adapted to new office layouts. Matthias Kassner, Vice President Product Marketing at EnOcean GmbH, takes a look at different connectivity architectures (wired, wireless, hybrid) and protocols (Bluetooth, ZigBee, EnOcean, PoE) to assess their usability and show how minimizing the need for maintenance is a key for increasing profitability of service-based offerings. Read more »

Resources | LpR Article | Research | Micro-Optics | Aug 13, 2019

Semi-Empirical Characterization of Freeform Microlens Arrays

LpR 72 Article - page 42: Microlens arrays (MLA) have been used for imaging and non-imaging applications for a long time as cost-effective solutions. Non-symmetrical beam shapes require more advanced non-symmetrical freeform microlens arrays (FMLA). The required FMLA molding tools convey a high cost and an iteration process is required for the final design. Oscar Fernández, Tamara Aderneuer, Rolando Ferrini from the Centre Suisse d'Electronique et de Microtechnique, CSEM, and Julien Duchene from ANSYS proposed a method to overcome these limitations based on 3D surface sampling, computer generation of a ray-traceable model and ray-tracing performance simulation and demonstrate feasibility for several commercially available freeform asymmetric thin-film diffusers. Read more »

Resources | LpR Article | Technologies | DC-Grids | Sep 17, 2019

LED Lighting Systems in Smart Buildings with DC Microgrids

LpR 72 Article, page 60: While electric motors for ventilation and air-conditioning systems were already DC-based in the past, powerful IT systems, LED lighting systems, photovoltaic systems with batteries and charging systems for electro mobility are now increasingly being used in modern building environments. They all need direct current (DC). Therefore, an obvious step is to equip modern buildings with DC grids. Carsten Moellers from Abalight discusses a number of unresolved questions and presents possible solutions in this article. Read more »

Resources | LpR Article | Research | Thermal Management | Sep 17, 2019

Thermal and Optical Challenges for SSL in Automotive Applications

LpR 72 Article, page 50: Solid State Lighting changed the lighting environment in automotive lighting almost more than in the field of general lighting. While efficiency of the devices increased and every few weeks new improvements are reported, thermal management remains crucial and a critical part of the system. Umut Zeynep Uras, Ahmet Mete Muslu and Mehmet Arik, from the Energy Efficient Electronics and Lighting Technologies Center (EVATEG), Department of Mechanical Engineering, College of Engineering at Ozyegin University, and Fatih Goren from the FARBA Corporation, explain the dependencies between photometric, electrical and thermal parameters of an automotive lighting application. Read more »

Tech-Talks BREGENZ - Dr. Scott Wade, Technical & Certification Manager, DiiA

Dr. Scott Wade has been the Technical & Certification Manager for DALI/DiiA since 2013 and has been an industry expert member of the IEC62386 standardization team for about 14 years. He was invited to hold a lecture at the LpS 2018 about the founding of DiiA for the purpose of taking over the DALI trademark from ZVEI and discussed measures that were taken to further develop the standard and its certification process and make the DALI concept future proof with DALI-2. Read more »

Resources | Commentary | Quality | Nov 15, 2019

Commentary: Providing Better Light Should Still be the Focus of the SSL Industry

J. Norman Bardsley, PhD - As President of Bardsley Consulting, Norman advises industry, government and academia on solid-state lighting, flat panel displays and energy efficiency, with special emphasis on diffuse lighting and organic electronics. Read more »

Resources | LpR Article | Special Topics | LiFi | Dec 16, 2019

LiFi as a Paradigm-Shifting 5G Technology

LpR 73 Articles, page 54: There are many misconceptions about LiFi, a wireless communication technology that uses the infrared and visible light spectrum for high speed data communication. Prof. Harald Haas, Professor of Mobile Communications at the Institute for Digital Communications from the University of Edinburgh, will explain what Light-Fidelity (LiFi) is and argue why it is a 5th Generation (5G) technology. Peak transmission speeds of 8 Gbps from a single light source have been demonstrated, and complete cellular networks based on LiFi have been created. Besides discussing numerous misconceptions, the potential impact this technology can have across a number of existing and emerging industries will be explained as well as new applications that LiFi can unlock in the future. Read more »

Resources | LpR Article | Special Applications | Artificial Intelligence | Dec 16, 2019

AI & Lighting

LpR 73 Article, page 62: Recently, Artificial Intelligence has emerged as an evolutionary force in almost every industry, demonstrating its potential to radically change existing processes. In common literature, AI is interchangeably used with Machine Learning for which various tools have already become commonplace. Henri Juslén, D.Sc (tech.), Chief Future Illuminator, Omar Nasir, M.Sc (tech.), Data Scientist, and Javad Nouri, M.Sc, Data Scientist at Helvar Oy Ab discuss AI on the context of the lighting industry where the scope of applications of AI is similarly quite broad, impacting the various stages involved in the lighting life-cycle such as design, installation, commissioning and configuration. Read more »

Resources | Tech-Talks Bregenz | Laser Technology | Dec 16, 2019

Tech-Talks BREGENZ - Julian Carey, Marketing Manager at SLD Laser

In 2016, Nobel Laureate, Professor Shuji Nakamura held a key note speech at LpS. As the founder of Soraa and SLD Laser, he named laser lighting as the next, innovative step and disruption in lighting. He emphasized the need to focus on light quality and the tailoring of LED lighting to the natural needs of humas, providing light that mimics sunlight as closely as possible. It was therefore self-evident that LED professional would invite Julian Carey, the Product and Technical Marketing Manager at SLD Laser, for a Tech-Talk when he was at the LpS 2018 in Bregenz. We asked him for an update on the status of laser lighting, business strategies and future prospects and how laser lighting has developed since Professor Nakamura's statements in 2016. Read more »

Environment | Commentary | Resources | Health + Environment | Dec 16, 2019

Care, Caution & Awareness Are Needed When Using LED Lights

Kyra Xavia is a researcher, educator and investigative journalist based in New Zealand. Her roles as general secretary of the Light and Lighting Research Consortium (LLRC), delegate for the International Dark Sky Association (IDA), New Zealand Ambassador for Women in Lighting 2019, and co-leader of the Dunedin Dark Skies Group, involve educating decision-makers and the public about the importance of responsible lighting, nocturnal placemaking and the value of darkness. Recognised in New Zealand and abroad for her advocacy in these matters, Kyra has co-authored research papers and published articles specific to this subject. Kyra has recently been awarded with The Dark Sky Defender Award. Read more »

A New Approach for Fast and Accurate Measurement of Light Emitting Diodes Junction Temperatures

LpR 73 Article, page 48: Junction temperature of LEDs is one crucial parameter to being thoroughly observed. In this paper, Ahmet Mete Muslu, Onuralp Isil and Prof. Mehmet Arik from the Energy Efficient Electronics and Lighting Technologies Center (EVATEG), Department of Mechanical Engineering at the College of Engineering Ozyegin Universitywill at first describe the importance of Tj for LED systems including RGB and white LEDs. Then they will present techniques from literature and recently in-house developed novel methods and a new Junction Temperature Measurement Device (EVAtherm). Results in selected general lighting and automotive lighting applications will be demonstrated. Read more »

Hermetic Polymer-Free White LEDs for Harsh Environments

AlGaInN-based white LED can easily achieve lifetimes of up to 100,000 h depending on junction temperature and current density. However, state of the art silicone encapsulated LEDs with powder-based phosphors reveal a strong dependence of field lifetimes on environmental conditions such as humidity, corrosive gas and air pollutant exposure. Dr. Michael Kunzer, Group Leader LED Modules at Fraunhofer Institute for Applied Solid State Physics and his colleagues, Ralf Schmidt, Andreas Zibold, Vasileios Georgiou-Sarlikiotis, Michael Arnold and Isabel Kinski propose luminescent ceramics as an interesting alternative to polymer-dispersed phosphors. This provides entirely new opportunities for the manufacturing of white LEDs. The authors explain the properties and advantage of this hermetic, light converting cap material and how to completely avoid polymers. Read more »

Transparent Material Considerations for UV Optics in Horticultural Lighting Applications

Advancements in UV LED technology have begun changing the horticultural lighting landscape. Research is still ongoing to discover the extent of benefits and best practices of using UV light in horticulture. Using optics in tandem with UV LED light systems can help reach performance goals and optimize growing. Although there are several UV- transmitting materials available, not all are equivalent or able to meet the requirements for UV applications. Justine Galbraith, glass engineer, and Sharayah Follett, market development manager at Kopp Glass, Inc. discuss the performance considerations of various UV-transmitting materials and how application challenges are addressed by integrating optical elements. Read more »

LED Driver for High Power Machine Vision Flash

Automation is nothing new and its demands are rapidly increasing, either in production or inspection. More sensors are used and many are based on direct or reflected light detection. Some work in the visible range and others work in the non-visible spectrum of light. LED lighting has become the standard in most applications as the solid-state light source offers numerous advantages over other lighting technologies. However, the LED lighting system is only as good as the peripheral components and LED drivers are one key element in many applications. Keith Szolusha, LED driver applications manager and Kyle Lawrence, associate applications engineer, identified the challenges for machine vision flash applications and propose a solution example with Analog Devices' LT3932 high speed LED driver. Read more »