Lighting has come a long way since the invention of electric light. With the arrival of the Internet of Things, the idea of remote-controlled lighting based on the human centric approach is becoming reality. The world of IT has entered the lighting industry. We will be looking at the challenges and possibilities this will bring to the lighting industry and how different solutions can be utilised to bring about a successful transformation of the existing lighting system into a future-proof one.
The Lighting industry has got fantastic opportunities to create new value with light. Trends in Lighting want to inspire designers, manufacturers, technologists and end users to capture these opportunities and opens with a keynote by the industry leader and designer Rogier van der Heide. With this keynote speech, Rogier will take you on a journey to new value spaces that have become within reach, now lighting is fully digital and we effectively find ourselves within a high-tech industry. But have you thought of what it takes to find new growth and new purpose for light? New value, and a future for our industry that is resilient, profitable, and enriching both for companies, customers as well as yourself as an individual? Rogier will introduce a new paradigm for collaboration and for doing business in lighting. A model that looks into the future instead of building further on the past. Within this “next level of the game”, key drivers are creative empowerment, individual lighting solutions, and our responsibility to deliver great lighting. Because like clean air and potable water, good light is a life-critical environmental factor for every human on this planet.
The goal of the project Repro-light (“Re-usable and Re-configurable parts for sustainable LED-based lighting systems”) is to initiate a transformation in the European lighting industry towards a circular economy. Through the development of an intelligent LED-based luminaire with modular, stackable architecture the project seeks to change the industry’s view of the LED luminaire into a customised, sustainable product with high functional value. The luminaire should easily be re-configured by all stakeholders involved and the product can in that way be updated to avoid obsolescence. The Repro-light luminaire is conceived to influence the customer’s well-being and health positively. It can also be adapted individually to the customer’s needs, e.g. the end-user’s age or chronotype. Repro-light does not only seek to satisfy the end-users but also wants to develop the luminaire in a way that the costs and time of manufacturing are reduced. Since the market shifts more and more towards increased individualization also luminaire production must be optimized to fulfil those requirements. The Repro-light luminaire will be developed in a modular way where the modules can be programmed to their intended purpose only – allowing for a seamless integration into Industry 4.0. In that way equal parts can be manufactured in... Read More
Lighting technology goes through a time of groundbreaking changes these days. The extensive application of the highly energy-efficient digital light source LED facilitates the generation of dynamic light spectra and luminous intensity distributions and the implementation of new lighting designs for special visual, biological and emotional needs. The integration of additional sensor-technologies (e.g. light- and motion-sensors, but also health-sensors and wearables) and the implementation of complex control algorithms will will support the transformation of current lighting systems into smart and adaptive lighting solutions that will instantaneously react to environmental alterations (e.g., time, weather) and individual desires (personalized lighting). But how can we exploit these new possibilities for the benefit of people? How can we start a sustainable social development (e.g. a “healthy” light) rather than merely creating technology driven gimmicks. The lighting industry observes current developments with regard to its emerging chances, and it appears as if euphoria is fading. The authors will present their positions based on own research and application experiences.
The Global Lighting Association has created its Strategic Roadmap for the global lighting industry last November 2017. The industry has witnessed two highly disruptive technology developments: Light emitting diodes (LEDs) and intelligent lighting systems. A third, equal important discovery was the 3rd photo-receptor in the human eye, providing scientific evidence that light not only enables vision, but also impacts performance and feelings of well-being. The world has many challenges, like globalization, climate and demographic changes. The challenges for the lighting industry are digitalization, new applications of intelligent lighting systems and the increasing demand for buildings supporting human health, well-being and productivity. Hence the value of lighting is moving from energy efficiency to the wider spectrum of quality of life and improved well-being. This transition requires new paradigms for all stakeholders – the industry, customers and users and particularly governments and regulators, who need to view the capabilities and benefits of lighting within this wider context.
BACKGROUND. Short wavelength (‘blue’) light is known to mediate ‘non-visual’ effects of light in humans. These effects, that go beyond the pure ‘visual’ function, can affect human wellness and performance, as it has been reported in previous scientific research in laboratory, office, education, clinical and aero-space setups. In healthcare research, lighting has been recognized in the fields of human factors, ergonomics, and systems engineering, as an environmental factor that can affect the quality of the delivery of care; in particular, clinician wellness and performance, and the occurrence of medical error. RESEARCH QUESTION AND HYPOTHESIS. The aim and novelty of this research is to study the potentially beneficial ‘non-visual’ effects of lighting in the clinical environment, to advance ‘patient-safety’. The hypothesis of this study was that clinician wellness and performance in the execution of clinical procedures at the emergency department (ED) could be improved through controlled, indirect, ‘blue’-regulated, full visible spectrum, tunable, solid state, ‘white’ lighting, compared to prevalent fluorescent lighting conditions. METHODS. To conduct our inquiry, we performed a randomized AB/BA crossover experimental study with ten actual ED clinicians that executed ED clinical procedures, under two lighting conditions, in a realistic ED clinical setting. The experiments took place at the... Read More
Zhaga is an open, global, industry consortium that aims to simplify the design and manufacturing of LED luminaires to accelerate the adoption of smart LED lighting solutions. It achieves its aim by standardizing the interfaces of components of LED luminaires, including LED light engines, LED modules, LED arrays, holders, electronic control gear (LED drivers) and sensor and connectivity modules. One of the latest interface types pioneered by Zhaga is the connectivity interface between the luminaire and its driver to an external sensor or connectivity module. This connectivity interface may have a mechanical aspect, to position the module on the luminaire, a power aspect, to power the module, and a control aspect, to control the luminaire from the module and to get status data from the luminaire. In its most complete form, the interface describes all these aspects and allows for an eco-system of sensor and connectivity modules that interoperate with an eco-system of luminaires. It is of great advantage, to have this interface as a standard; an installed base of luminaire equipped with the interface stimulates the development of a wide range of modules for a variety of applications, which in turn adds value to the luminaire, and drives an... Read More
The presentation will give an overview of what regulators and consumers expect of products over the next 5-10 years and explore what this means for lighting product design and business models. The EU is driving change through it’s Circular Economy strategy and an ambitious action plan, that address the products entire life cycle: a strategy to regulate the quality and variety of plastics used in products, increased information requirements on the chemical substances and critical raw materials contained in a product, promoting increased repair of household EEE products, requiring removable and replaceable components, additional waste collection and recycling requirements. All these proposals have a direct impact on the design and marketing of lighting products in Europe. The presentation will explain how the lighting industry, within LightingEurope, is engaging with regulators, consumers and NGOs to shape a policy framework that achieves the objectives of a Circular Economy and supports the industry’s competitiveness and innovation.
There is world-wide demand for more efficient products to reduce energy and resource consumption. The Ecodesign Directive provides harmonised EU-wide rules on the energy performance of products, and is complemented by mandatory energy labelling rules. In recent years EU Ecodesign policy has steered away from only energy-efficiency to address the wider environmental impact of a product, and now addresses issues such as materials efficiency, reparability and replaceability of components and increased requirements relating to the product’s end of life. The proposed new EU rules on ecodesign and energy labelling for lighting products that will be published in Q3 2018 introduce significant changes for the lighting industry, from the phase out of conventional technologies to increased performance and environmental requirements for lighting products. The presentation will explain the process and status in the development of both policies. It will touch upon key terms from the implementing measure document, such as scope of products affected, removability requirements, time horizons, the position of special purpose lamps, the definition of tolerances, endurance testing as well as the potential phase-out of some conventional technologies under EU RoHS rules restricting substances. It will go into details on the planned Energy Labelling Database, explain the attempts to... Read More
At the advent of the European Cybersecurity Act, this question gains momentum. As a presentation has been held by UL already at LpS 2015, this presentation will focus on news in terms of regulatory and standards developments, technology developments such as IoT and Cloud management systems as well as the cybersecurity landscape, which embraces both poles. Cybersecurity needs to be considered for smart lighting devices, be it in the B-to-B or in the B-to-C space. In the meantime standards are available to evaluate smart lighting products as well as Cloud based management services effectively and efficiently. For manufacturers there is a need to tackle cybersecurity proactively to prevent harm to their company or their customer’s one or to the consumer. As modern lighting solutions are supposed to have a long life time and little or no maintenance options, cybersecurity resilience needs to get built-in heads-up for such time spans – also to protect the manufacturer from potential liability issues. In the presentation we will show the big picture on how to take control over cybersecurity and compliance issues, what can be done today and what is needed to be prepared for tomorrow. A engineering based approach to cybersecurity is most... Read More
The role of sunlight in influencing eye-ball growth has been well established. Recent research has established the link between myopia (short-sightedness) and reduced exposure to adequate levels of sunlight. Other researchers have established the wavelengths of visible light that trigger the so-called ‘retinal dopamine response’ instigated by the non-visual receptors, intrinsically photosensitive retinal ganglion cells (ipRGC’s) as the primary zeitgeber for the circadian rhythm. Laboratory research using dopamine agonists and visual deprivation experiments in mammals supported by epidemiological evidence now suggests the retinal dopamine response plays a central role in the neural and neuro-transmitter control of eye-growth and therefore the pathogenesis of myopia. Myopia is now regarded by WHO as a global epidemic. On average, developed and developing nations have experienced a three-fold increase in myopia over the past three decades. For example, in South Korea and China (and most of eastern Asia), 80% of high school graduates and 95% of university graduates are myopic. Apart from the personal costs, inconvenience and disability, myopia brings elevated risk of ocular morbidity for many of these sufferers in later life (glaucoma, macular degeneration, retinal detachment and cataract) which in turn poses the risk of an onerous burden on health and welfare costs... Read More
Moderator: Jens Herter (Coordinator Standardization, Zumtobel Group) Panelist: Dr. Dee Denteneer (Secretary General, Zhaga Consortium) Panelist: Dr. Scott Wade (Technical & Certification Manager, DiiA) The trends in lighting towards digitalisation, intelligent lighting fixtures and the merger of lighting with the Internet of Things (IoT) all call for standardization to enable plug-and-play interoperability and to accelerate adoption of smart lighting technologies. There is a market demand for standardized interfaces that enable sensors or communication devices to be seamlessly connected to LED luminaires. A modular approach with standardized interfaces supports the development of a broad range of such devices, and allows product ecosystems to flourish. Luminaires are future-proofed and can be upgraded in line with the ongoing evolution of sensing and connectivity technologies. There is also market demand for intelligent luminaires that can collect and report data – such as energy metering and diagnostic functions – in a standardized format. This enables advanced lighting control and data analysis, and the luminaire should also supply the required power to all connected devices. Having developed relevant specifications in this area, the Digital Illumination Interface Alliance (DiiA) and the Zhaga Consortium (Zhaga) are actively collaborating to define truly comprehensive specifications as the basis for broad... Read More
The absence of natural light causes serious health problems in humans. Although known since ancient times it was only after the recent discovery of the so-called intrinsically photosensitive retinal ganglion cells (ipRGCs) that specialists started to understand the responsible biological mechanisms. This discovery boosted the research and development efforts on lighting solutions that exploit non-visual effects to promote human health (broadly known as Human Centric Lighting, HCL). In particular, being the most important “Zeitgeber” for circadian rhythms of our inner clock, light is a powerful tool to trigger effects such as alertness, sleepiness and cognitive performance and consequently, a large deal of research and development has been committed to the development of color tunable lighting solutions that match daylight variable spectral power distribution, SPD. However, the preferred white color coordinates aka white tone depends strongly on the application (e.g. office, retail, home, etc.), the illuminated objects (office tables, cloths, food, etc.) and the brightness and not surprisingly white tone variation is not desired for many applications. Fortunately, since ipRGCs do not participate in vision, different circadian effects can be produced by visual stimuli of the same color coordinates (metameric stimuli). Metameric circadian SPDs for display applications are a subject of... Read More
Light is so critical as air, water, and food to our daily life. Conventionally, the light on vision plays a major role in lighting industry. In the last two decades, much has been learned regarding the non-visual effects of light on human circadian entrainment. Light synchronizes our physiological and psychological rhythms to the 24-hour rhythm of the ambient changes. Furthermore, light consists of alerting and activating effects, impacts on mood, and melatonin levels in humans. For the elderly people, adequate environment to compensate for increasing frailty and sensory loss are crucial. Normal age-related changes to the eye decrease the amount of light reaching the retina impacting both vision and circadian rhythm. Some attempts have been made recently to conduct white-tunable lighting and vary lighting levels and CCT/spectrum for health and wellness. However, how to translate such Human-centric Lighting (HCL) concepts proven in laboratory studies into built environments are still in early stage and lack of largely proven practices and strategies on an operational level. Specifically, the necessary requirements for the development and effectiveness of HCL design strategies and actions in nursing homes have not been formulated in a rigorous and reliable manner. The design consultants are faced with the complex... Read More
The introduction of solid-state lighting (SSL) has disrupted the global structure of the lighting industry. The potential for substantial energy savings and reductions in the environmental impact of lighting have led to considerable interest by national and regional governments in encouraging adoption. The most intense efforts have been in China, where federal, provincial and local governments have made substantial investments to drive the transformation and expansion of the lighting industry. Thus, although most of the fundamental discoveries that led to the development of LEDs were made in Japan, Europe and North America, Chinese manufacturers are capturing larger and larger fractions of industry revenues and profits. There are many ways in which governments can influence industrial transformation. • Support for research and development • Education and retraining of skilled workers • Subsidies or barriers to new manufacturing facilities • Protection of domestic industry • Market development • Quality control The history and impact of government activity in China will be compared with that in Europe and North America. In 2017 SSL products gained a share of 65% in the Chinese lighting market (measured in unit sales, rather than value). The penetration of the installed base reached 35%, leading to energy savings... Read More
Scientific Partnership in Lighting (SciPiL) SciPiL is a Network initiated by Luger Research. It connects research organizations and the lighting industry, enabling knowledge sharing that triggers the development of vital innovations in the lighting domain. The SciPiL Showfloor-Tour opens up possibilities to meet SciPiL partners on their booth in the showfloor, get information about their research activities and discuss your matters of interest with them. Objective: Establish or enhance partnerships between key scientific organisations and the lighting industry. For more information, please visit: https://www.scipil.com
When a building owner or building manager decides to invest in implementing a lighting control system, there are many challenges to overcome, which relate to balancing cost, simplicity and scalability. With the proven benefits of how lighting control can reduce energy costs, it still nonetheless can require a significant initial investment. The lighting control system must not only be intuitive to operate but even more importantly, it must be simple to commission and to modify settings post-installation in order to minimize service charges. But the key issue is scalability, which affect both cost and simplicity. If a building manager wants to future-proof their lighting control installation to eventually support building automation systems like BACnet and KNX or harness the power of the Cloud or even leverage a new technology/standard that hasn’t been released yet, does the building manager need to invest in a complicated and costly system or is there a strategy to limit the initial investment and only incorporate extra functionality and technology on an as-needed basis in a seamless and cost effective way? This presentation will cover the differences, strengths and limitations of different technologies such as BLE, EnOcean and ZigBee and discuss how and if each can... Read More
With the integration of LED technology, lighting has evolved from a basic, functional feature to a distinctive feature with high-value potential in automotive. Indeed, LED technology has given manufacturers the opportunity for strong differentiation via lighting design and additional functionalities. This is particularly true for exterior lighting which is under deep mutation (in terms of both technology and supply chain). Indeed, the integration of new Solid State Lighting (SSL) technologies is transforming automotive front lighting, RCL (…) systems and their applications, offering more design flexibility, increased efficacy, and new functionalities. LEDs are rapidly gaining popularity as their cost decreases and performance increases (i.e. efficiency, luminance, package size). For example, full LED headlamps that first saw commercialization in 2008 on luxury cars like the V10 Audi R8 have since penetrated the C-segment vehicle market in 2012 (with the new Seat Leon), and are now being commercialized in emerging markets. Nowadays, nearly all OEMs/Tier-1s have developed full LED-based headlamp systems. Laser and OLED sources are still emerging technologies but could also support the development of new functionalities: laser-based headlamps could enable long-distance night vision (up to 600m) whereas OLED RCL will match with a design shift from 2D to 3D light source... Read More
Daylight is the preferred light source of choice for human centric lighting applications in the built environment, as the human visual system and physiology has evolved under this environmental condition. Conventional white LED light sources pump on blue (≈450nm) and show an unbalanced spectrum with a prominent peak in the shortwave region of the visible spectrum. This disturbed emission might be associated with several discomfort and health issues. Innovative technologies in optoelectronics based on purple dies and multiple phosphors offer an emission very similar to daylight, particularly indoor after the glazing media. We propose to consider the light provided by full spectrum LEDs as indoor daylight in building standards and regulations.
Recent research suggests that the LED penetration rate in general lighting is between 60 % – 100 %, depending on region and application. This leaves luminaire manufacturers with the challenge that the innovators margin (using LED technology) is decreasing, since the LED technology is now seen as standard technology. Therefore “LED” is no longer the selling point for a luminaire, but more often the price. This poses the question, who is best positioned for becoming stronger during such a price battle. It will be those who further innovate their luminaires and increase efficiency in their production. Setting the background with the above mentioned points, the presentation will kick-off by looking at further, manufacturing related challenges, such as error prone manual assembly, need for flexibility due to an increase in project business, in-house manufacturing (often associated with high costs) vs. buy in (often associated with a lack of flexibility). The focus of the presentation will be on the luminaire manufacturing process and will evaluate the different methods (manual, semi and fully automated) and its benefits as well as limitations. Typical luminaire manufacturing scenarios will be reviewed and it will be discussed how those could be improved. A major part of the presentation will show examples... Read More
Commercial buildings are rapidly evolving to become more efficient, more comfortable, more flexible, and in general more adaptive in relation to their use and to the occupant needs. Internet of Things technologies are booming with the purpose of delivering smarter, more automated, more connected system in existing and new buildings. Large scale deployment continues to present a challenge for the industry because systems and practices are still highly siloed from design to operation prospective. Poor and costly integration between different systems, unclear ownership of IoT infrastructure and process gaps to manage network based connected solutions represent the three bigger obstacles for large adoption. The ability to migrate lighting controls to IP-based infrastructure makes the lighting a key IoT building asset that can be controlled synergistically along with other building functions. More integration means not only better control leading to drastic energy saving, increased occupant’s confort and productivity performance, but also more meaningful data being collected by distributed sensor system as part of lighting network infrastructure. The use of IP lighting in commercial buildings is growing rapidly, and several large-scale projects are getting underway in 2018. A real life large scale installation will be used to illustrate the unique role that... Read More
Despite great success in the market for high-end cell phone displays, OLED technology has yet to achieve significant entry into the general lighting market. This is mainly due to the relatively high cost, but also by manufacturing problems in achieving the innovative form factors promised in concept papers and prototypes. Although steady progress is being made in device performance and fabrication techniques, the production of exciting new products at affordable prices remains challenging. This talk will assess the progress in commercialization and discuss the obstacles that remain to achieve high-volume sales. The challenges can be gathered into three categories. Performance: • Organic molecules offer a very efficient way of converting electricity into light without the formation of a strong blue peak in the spectrum. However, most of the light is trapped inside the device. Substantial progress has been made in enhancing light extraction, but solutions that are compatible with flexible substrate are still needed. • Lifetime concerns have been ameliorated by the development of multi-stack structures. However, these solutions increase the complexity and thus the cost of the device. Further development of stable blue emitters will be necessary to keep up with future efficacy increases in LEDs. • The angular... Read More
There is little argument that lighting is well positioned to serve as the sensing backbone for the IoT in our built spaces. From there, the crystal ball gets a bit hazy to tell us when, or perhaps more importantly, how that will really happen. While we all love our technology, recent product introductions in other arenas, such as mobile devices, could be suggesting that tech just for the sake of tech, may not sell like it used to. There has to be a business case for sensing. In this paper, we will examine ways in which the business case for rich sensing in our lights will evolve in a value-adding and logical way, from the current “occupancy only” type of sensing, into progressively more expansive sensor capabilities that will transform both the function and value of our lights. Areas to be examined include: • The importance and payback for optical sensing within the luminaire to enable closed loop control, performance maintenance and spectral validation • The progression of capabilities to include measurement and management of bio-active spectra, such as those affecting circadian rhythms and other physiological responses • How horticultural lighting will pave the way for the incorporation of enhanced... Read More
Jan Denneman – Panel Moderator Enough quality light during day time helps people concentrate and learn better, be more creative and alert. It also helps them sleep better at night. It makes them feel better and develop fewer problems with vision. It is vital that people get enough light every day. The best light to realize these effects is natural daylight. Unfortunately, people spend most of their lives indoors, with far too low light levels to create above effects. In the panel we will discuss why it is important that people get enough quality light every day, also indoors. And we will discuss how we can make it happen that indoor lighting levels is not only focussed at vision but also on creating the positive biological effects of human centric lighting.
When you think about efficient lighting the first thing that comes to mind (and often the only thing) is the efficacy of the LED. However, as LED efficacy improvements are nearing diminishing returns of optimization, what will enable the next generation of significant improvement? The ‘Race to the Bottom’ for LED manufacturers leaves it up to lighting system manufacturers to develop the technologies necessary to create the next level of improvements required for a healthy industry. Advancements in the methods that integrate LEDs into lighting solutions will open new opportunities for improving efficiency, enable innovative form factors and introduce new functionality for SSL solutions. The Delivery of light, the Integration of the package it is housed in, the Connectivity, and the Flexibility of the form factor will all become significant contributors to the overall efficiency of SSL solutions. In conjunction with these integration advancements, a more holistic approach to design, engineering and manufacturing will enable the lighting solutions of the future. An approach to quantify the total lighting solution efficiency and effectiveness will be presented. Case studies will then be shared which highlight how these engineering tools can enable innovative lighting solutions when used in conjunction with advancements in integration... Read More
Everybody is talking about Smart Lighting, the whole Lighting Industry stands in the middle of radical changes. The market cries for the extra value – but what is the extra value? Are we able to sell the extra value? The same topic is valid for the whole IoT market. Where we are in the moment? Let’s have a look to the innovation process and technology change in other markets. So what are our wishes and where is the vision? No question Smart Lighting will change our future but where is the way? Is it Bluetooth Mesh and will DALI survive? Is Lighting Industry really in the pole position for smart buildings? Finally let’s come back to reality and see what is possible in the nearest future.
With the advancement of solid-state lighting, beam shaping became more difficult and architectural lighting designers essentially lost the ability to easily set scenes when using LED luminaires. Though it’s still possible to use accessories (barn- doors, snoots etc.) or snap a lens to the front of an LED luminaire, they are not the easiest or most common solutions. Lamp manufacturers have yet to deliver LED PAR lamps comparable to halogen or metal halide form factors, output and light quality. The dominant lighting solution is a COB (chip-on-board) light source that is integral to the luminaire leaving a reflector change as the only, yet difficult and unrealistic, option. Lighting designers have essentially lost the once common ability to shape beams. We suppose that some miniaturization of the entertainment industry’s motors and mechanicals could enable a beam shaping solution for lighting designers, though it is unlikely that budgets, reliability and form factors could be achieved and maintained. However, work initiated a decade ago in the camera and imaging segment has evolved into a technology that once again gives lighting designers the ability to shape beams from a variety of luminaires and takes it one step further by making the function digitally dynamic.... Read More
The horticultural lighting market’s current boom is driven mostly by greenhouse applications, for which artificial lighting is used to compensate for natural light variations and increase production yield. For these applications, traditional light sources like fluorescent and high-pressure sodium (HPS) lamps are currently the most popular solutions. However, LED technology is catching up and recent developments have allowed the technology to enter the horticultural lighting market. But greenhouse applications represent only the tip of the iceberg in this business, and new applications, mainly driven by urban farming, are likely to make the horticultural lighting market boom in the mid/long-term. Nowadays, arable land is usually far from big cities and metropolises with millions of people. And as consumers become more conscious of how and where their food is produced, farmers are finding it more difficult to keep up with urban growth. City farming represents a potential solution to handle these needs and challenges by allowing for the growth of plants, fruits, and vegetables in a confined environment, on multiple layers (to maximize production), and without sunlight (i.e. using only artificial light). In this context, we estimate the 2017 horticultural lighting market (i.e. system level) to represent a business of ~$3.8B. And... Read More
The technical intricacies of an LED system design can be astonishingly complicated. Evaluating options becomes extremely time consuming and leads to risky decisions. LED manufacturers’ product selectors or simple parametric simulators can be helpful however not sufficient for full system optimization. The next generation tools will need to be application oriented rather than LED centric, to simulate a system level solution not just the LED components, to support a wide range of options from multiple manufacturers, to address mainstream illumination as well as emerging ones such as horticulture or non-visible solid state light source applications e.g. UV. The next generation tools are available today: come and discover them.
Delphi4LED  is an H2020 ECSEL European research project involving 15 partners across Europe. Its ambition is to deliver a complete model to assess the performance of complete LED luminaire systems even before prototyping phase. This is achieved thanks to massive characterization and the use of a compact thermal models (CTM)  plugged into a multi-domain chip level LED model combining thermal, electrical and optical physics . Besides electrical and optical behaviors, thermal behavior is a key physical phenomenon that has to be taken into consideration to model LED luminaire systems and therefore predict their performance.
Connected Lighting as the base of IoT systems is in everybody’s mouth. Industry players so far are experimenting with and testing business cases for IoT applications that are built on top of the Connected Lighting infrastructure. Unlike in other industries such business cases – in many cases – are not complete straightforward and require a substantial effort for prototyping and measurement based on the understanding the specific’s customer’s needs. The lecture takes a view on why this is the case and why it seems so tricky to build business cases here. It takes a look at the capital expenditures for Connected lighting solutions and their impact on operational expenditures. It further analyzes the position of multiple type of companies/players in the value chain and delivers a perspective on who is best positioned under what circumstances to build a successful business. Finally the lecture will cover successful deployments of IoT installations on top of the Lighting infrastructure and elaborate on reasons why such installations have been successful and can be the foundation for a sustainable and successful business model.
Hands-on workshop in order to experience the optical material PMMA. Targeted are all professionals involved in product design with plastics. Background Thermoplastic materials have been key enablers for innovation and have contributed to the development and progress of society. Transparent as well as opaque plastics have been used in the lighting industry for many decades and the share is ever increasing with LED light sources. Motivation From a materials manufacturer’s point of view it can be concluded that material knowledge is very good, if not excellent, within the technical and production staff of plastics processing industry. Designers, however, need a broader understanding of combined properties. Characteristics such as haptics, aesthetics, optics and ageing properties must be known – in addition to general applicability and processing – for designing a good product. Content Expressly not intended is to getting hard facts on optical, rheological, thermal or mechanical properties across to the audience. Instead, each participant is prompted to work and play with PMMA as the representative optical thermoplastic material. Many aspects and functions which the acrylic polymer has to fulfill in an e.g. luminaire over the entire lifetime are addressed. In detail, the following topics will be experienced, developed and presented: Haptics Optics... Read More
The office world is currently undergoing big changes. New concepts like shared offices, co-working spaces and a growing demand of home working models which are compliant to office standards are major challenges. The furniture industry is adapting to those requirements leaving the lighting Industry behind. Therefore it is time to find adequate lighting solutions for these new work models and environments. Looking at the complex demands of architecture and a user-centered office design, it is clear that the ceiling plane is not the most convenient place for the light fixture. The beloved freestanding luminaires have always been a crutch: Too big to be flexible, freestanding task lights add an undesirable new horizon into the open space and always lead to a struggle between users in terms of individually desired light quality. With my presentation, I would like to display the development process of an innovative lighting concept leading to a new light fixture. The set of objectives for the new task light was to create an object which does not compete with the architectural concept of modern offices, to provide a fixture as flexible as a desk and a chair and to give the user the freedom of personalized light settings. The key... Read More
AlGaInN-based white LED can achieve lifetimes of up to 100000 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. The reason behind this is the design of current white LEDs. They consist of blue light emitting chips and yellow phosphor, which is excited by the blue light and in total produces white light. The yellow phosphor powder is dispersed in a polymer or silicone matrix and is either placed in a layer directly on, or in a lens above the chip. Continuous improvements of the LED chips enable current and luminance densities, which lead to an extreme photo-thermal stain of the phosphor converter even without external influences. Furthermore, the polymer matrix itself has low mechanical and thermal reliability and is permeable for humidity and gases. High ambient temperatures or penetrating pollutants can then accelerate browning and corrosion inside the LED package. This reduces the lifetime and causes color shifts, which the eye can easily recognize when comparing different LEDs. The silver reflectors inside the package and chip are particularly sensitive in... Read More
In 2018, hardly anyone doubts that connected lighting controls are the future of the lighting industry. However, the last couple of years proved how challenging this environment is for wireless communication technologies. The market remains highly fragmented and customers remain locked to proprietary solutions. Scalability still remains a major issue as wireless systems available so far were not able to provide wire-like reliability and responsiveness in large-scale installations. One might think that relevant solutions should show up fairly quickly – especially considering how big the prize is for those who figure out how to address these problems. Still, connected lighting seems to be stuck somewhere between the “innovators” and “early adopters” stages of the technology adoption curve. The fact that even the most proven wireless solutions were unable to address these challenges shows one thing. A radical change is needed in how we approach the fundamentals of connected lighting. Network technologies we commonly use today are based on a host-centric paradigm. Perpetual connectivity and the so-called end-to-end principle have become a design framework in computer networking. This is how the Internet infrastructure is organized. This approach has worked thus far but experts say it won’t be sufficient to handle the... Read More
Diffraction gratings and other high-precision optical elements are widely used in sensors, analytic systems, laser-applications and various other fields. However, due the very small structural sizes, even below the µm range, and the high accuracy requirements, their mass-production possibilities are limited to few techniques such as hot embossing or nanoimprint lithography. NIL also has the restriction that such a device is fabricated from different materials: A resist is required for the structures, the macroscopic geometry is normally defined by a blank, and an additional coating might be required. To date, cheap mass-production of gratings is realised by replication via roll-to-roll on foils or hot embossing on thin substrates. Hence, the structures are on flat and/or elastic surfaces, which limits their application. To obtain rigid optical components, even with curved surfaces, such micro-/nanostructures are normally manufactured on top of a blank substrate. However, thereby two more points have to be considered: firstly, the surface geometry of the blank must be fabricated very precisely, e.g. by cutting glas, and secondly, the macro-/nanostructures have to be added on top without interrupting the surface’s geometry and the grating’s structure. This elaborate process chain causes the prices of such elements to remain relatively high. Microstructures... Read More
OpenAIS (www.openais.eu) is a project sponsored by the EU in the Horizon2020 program where 10 leading European companies cooperate. In the past 3 years a system architecture was developed that exploits IoT based professional lighting. Its vision included the following assumptions: 1. Lighting will offer the infrastructure to integrate devices and deliver additional functionality beyond lighting 2. In IoT we will use existing ecosystems and standards to create our solutions 3. An IoT-based Lighting system in professional environments demands openness and interoperability as professional customer will avoid vendor lock-in In 2014 the goals of the project were to create an open architecture (standard) for lighting control systems, allowing multi-vendor systems, based on (emerging) IoT-standards and ecosystems and to validate this approach by a large-scale pilot in an actual office environment. Demonstrating the promises of interoperability and third-party mix and match was an important objective of the pilot. In 2018 the results of the large-scale pilot have been demonstrated. In this presentation we will report back on the main findings in view of the original project assumptions.
Content summary • Heat flux in chip-on-board LEDs • Temperatures of junction, case and surface temperature • Package with bare and encapsulated chip • Phosphor layer of silicone and ceramic matrix • Parallel thermal resistances Several failure mechanisms appear in LED packages at diverse locations. Since the processes are thermally accelerated, the knowledge of corresponding temperatures is important to calculate the package’s lifetime. Moreover, the emitted radiation is reduced at high temperatures with different ratios considering the chip and phosphor. Packages for chip-on-board LEDs varies in the geometry in comparison to high power LEDs. Especially the surface area of the silicone encapsulation is larger than the die’s dimensions in many products. This leads to new considerations of the heat flux, in order to estimate the package’s thermal management. The three sorts of heat transfer are determined for a COB module to find out the physical background of the dissipated heat. The heat flux inside the package leads to different temperatures at the junction, the temperature measurement point, and the silicone surface. All of them should be identified for the application. In packages with volume emitting phosphor a main driving factor for the silicone’s temperature is the converted blue radiation, emitted... Read More
Every LED driver is composed by one, two or sometimes three different topologies based on power electronic components: magnetics, MOSFETs and DIODEs working under hard conditions. The electronics reliability is limited by the stress that these components are able to support. More and more, LED drivers are demanded with a wide range of output power, so the operation of this kind of topologies integrated in the LED driver has many variations far away from its optimal design operation. This is especially critical in topologies like LLC resonant topology (going out of ZVS operation or third resonance problems) or Power Factor Corrector Booster topology (increasing switching power losses due to very light load operation). Guaranteed reliability without an over-cost in materials involves a fitted development by means of optimal magnetics design and knowing the behaviour of that topology in all range of the LED driver operation. Using topologies simulations, magnetics involved in the LED driver can be designed in an optimal way, fitting them into the application. Using this way of design, all functional parameters, such as frequency operation or Duty Cycle can be estimated and fixed in final application. It is especially interesting if we may foresee Conducted Electro-Magnetic Interferences by setting... Read More
In this paper a new revolutionary approach to optical beam shaping for lighting applications is presented. The optical devices, developed by IQ Structures under the trade name Nanoptiqs are based on principles of diffraction, which are applied in a novel way 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. The surface (or volume) properties of the micro/nano structured optics are calculated with details as small as 10 nanometres, generally in three-dimensions. High complexity modelling of the light interaction with matter at nano-scale makes this task extremely computationally intensive. Moreover, manufacturing of three-dimensional optical nano-structures requires application of state-of-the-art mastering techniques with extreme spatial resolution such as electron-beam lithography, direct-writing based on multi-photon absorption and similar. These techniques together with in-house developed computational tools and high-precision mass-replication technologies stand behind Nanoptiqs unique properties, which promise an important role with these products not only in laboratory applications, but also in high capacity industrial production. This contribution is focused on the explanation of physical principles of Nanoptiqs elements, description of selected approaches to computer modelling of optical nano-structures and... Read More
Recently, high luminance has become a key requirement for LEDs used in directional applications such as stage lighting, sports lighting, and retail. Increased luminance (flux per LED luminescent area and emitted into a solid angle) leads to narrower beam angles, smaller secondary optics, and increased light usage fostering energy efficiency. This presentation will review product architectures and technology that aid increased LED performance in terms of luminance.
Nowadays complex 3D optical components with (sub-) microstructures on the surface of bulk optics become more and more attractive for different applications. Such examples can be found in lighting systems, optoelectronics, photonics, image processing, machine vision and motion control systems. Adding an additional optical functionality to a bulk 3D optic by placement of microstructures on the optic’s surface has enormous potential in terms of miniaturization of optical components, improvement of system integration and reduction of costs. Nevertheless, the development of complex 3D optical components with novel functionalities poses some technological challenges in design and fabrication. In this work, we report on a novel method to fabricate unique optical components, which exhibit the concept of ‘micro on 3D macro’. To demonstrate the possibility for rapid-prototyping of such optical components, 3D printing, direct-write laser lithography and 3D molding are combined into a novel process chain. The individual fabrication steps are discussed in order to point out the critical issues such as obtaining an optically smooth surface and shape accuracy of the 3D printed macroscopic objects to be suitable for the use in the field of optics. Some examples of successfully fabricated complex 3D optical components combined with patterned surfaces are demonstrated. These... Read More
While control is already used in many lighting applications, the share of controllable systems and the extend of control is expected to increase significantly in the coming years. One of the main motivations is the reduction in power usage that can be achieved, without affecting user value. The efficiency of LEDs has increased rapidly the last couple of years, but most of the prognoses imply that the efficiency will stabilize at around 200 lm/W. The next important area for energy efficient lighting will therefore be intelligent and user-oriented lighting controls. In an efficient lighting system (indoor as well as outdoor) that includes occupant detection and daylight harvesting, the energy savings can amount to 50% – 70%. Another reason is the increased focus on IoT, tunable white and human centric lighting, all requiring connectivity, control and extensive use of dimming. Dimming of LEDs do however introduce some new challenges that has to be considered before specifying a new system. One common pit fall is to assume a constant efficiency of the driver when dimming. In a simple use case control is added to dim the lights to 50% output in 50% of the time, this should give a saving of 25%.... Read More
In recent years, Chip-Scale Package (CSP) have been introduced to certain lighting applications. Compared to conventional Surface-Mount Device (SMD) high-power LEDs, the CSP technology has improved on compact design and thermal management. Nowadays, the adoption of Direct Mountable Chip has increased to ensure reliability and optimum performance of LED lighting fixtures. In this paper, we first explain how the Direct Mountable Chip technology is providing similar advantages as CSP, over SMD package. We also discuss the benefits of the new solution to overcome CSP limitations at module level by reducing crosstalk to improve optical emission and color shift. Then, we give an outlook of the Direct Mountable Chip integration in wider lighting applications by maximizing flux density and introducing color LEDs.
LED, a new scientific light gave us a chance to think about the essence of light, in other words, what light is for human being. Considering about light in association with our daily lives, human history, culture and art, we are led to realize that light is not only for looking at something. It has a deep meaning for our biological functions, emotion or spirituality. This is easy to understand from the general theory, “Human biological functions or the structure and mechanism at molecular and cellular level has been optimized to adapt to nature. (sunlight and its cyclic time variation in this case)” The New LED spectrum technology “TRI-R” developed based upon above background to realize the truly human centric light environment will be introduced. And the change in quality of light caused in these 20 years by the appearance of LED, visual changes and predicted influence on human will be presented with various optical data and the results of chronobiologic verification operated by an advanced research institution in Europe. It is expected that this discussion shows one of the directions for human well-being.
“Electronic converters are widely used in order to supply a LED module. The electrical interface between both has not been standardized over many years. At first glance this interface appears to be trivial, however a professional matching requires considerations of medium complexity. Inappropriate combinations can impact the reliability of the luminaire or degrade the quality of light. In partnership to ZHAGA a Module-Driver Interface Special Interest Group, short MD-SIG, has been founded. MD-SIG provides a free download of interface specifications: http://md-sig.org/specifications/ The power interface specification describes which electrical information shall be provided in the data sheets of converters and LED modules, how to interpret this information and practical tests for verification. The aim is to provide the data and a method which allows luminaire manufacturers a simple, but reliable matching. The development of LED follows the main goal to design a light source. Strong focus is on nonelectrical properties like efficiency, optical properties and cost. MD-SIG avoids to put additional burden in terms of electrical requirements and foresees wide parameter ranges in order to cover also future LED generations. Deep knowledge about the system interactions is required during the development of the converter. The considerations have to cover basic matching... Read More
Microlens arrays (MLA) are used since long for imaging and non-imaging applications. Because of the small dimensions of they can be cost-effectively replicated onto flexible thin-film substrates and retain great deal of the substrate flexibility. Standard quasi-spherical microlenses can be realized using photolithography and subsequent self-assembled photoresist thermal reflow. Nevertheless, such microlenses fail to comply with stringent requests such as for example non-symmetrical beam shapes, which require more advanced non-symmetrical aka freeform microlens arrays (FMLA). Despite being compatible with cost-effective replication processes, the manufacturing of FMLA molding tools conveys a rather high cost which all too often increases markedly with increasing tool area. In addition, it is rarely the case that the first design meets the specifications and often several design-fabrication-testing cycles are required thus pushing-up the cost beyond the reach of many Companies. Unfortunately, the experimental characterization of small samples is normally unrealistic due to handling issues and experimental errors (e.g. alignments, output power, large source beam diameter, small detector aperture, etc.). Here, we propose a method to overcome these limitations based on 3D surface sampling, computer generation of a ray-traceable model and ray-tracing performance simulation. The proposed approach is demonstrated for several commercially available freeform asymmetric thin-film diffusers.
DALI-2 is extending and enhancing the strengths of DALI as a dedicated, standardized protocol for digital lighting control. For many years, the lighting community has installed DALI systems that are robust, scalable, cost-effective, reliable and flexible. But now, for the first time, DALI-2 has brought standardization to products such as sensors and other input devices, as well as application controllers, which are the “brains” of a DALI system. DALI-2 now extends to all devices in a lighting-control system. Furthermore, with its rigorous testing and verification procedures, the DALI-2 certification program from DiiA brings the promise of significantly-improved interoperability of products from different vendors. This presentation will describe the latest updates to the international DALI standard, IEC 62386, and the ongoing development of the DALI-2 certification program. At the time of writing, over 160 DALI-2 certified products are listed in the DiiA online Product Database, from a wide range of DiiA member companies. We will explain how DiiA is creating new test sequences to allow companies to verify product compliance with the different parts of IEC 62386, which cover different product types and features. These include, for example, control gear for self-contained emergency lighting; control gear enabling colour control; and various... Read More
The technical progress of LEDs in the last years has enabled new luminaire designs in the General lighting market. Due to the increase of efficacy, less LEDs could be used and with the reduced thermal load, heatsink sizes could be minimized or heatsinks could be omitted at all. As a result the luminaires became smaller, thinner and less heavy. In contrast to the luminaire world, LED retrofit lamps have a strictly defined form factor and there has always been a strong demand to achieve the same appearance as during the last one hundred years. However the first LED retrofit lamps had a quite different look compared to the “good old” incandescent bulbs. With the increase of LED efficacy, the bulky heatsinks disappeared and the LED bulbs looked more like their classical predecessors. But only with the development and continuous improvement of the LED Filaments, real incandescent look-alikes were possible. One of the big technical challenges when using LED Filaments, is the thermal design. The main cooling path of an LED Filament lamp is going from the LED directly through the gas filling of the bulb. This requires a good understanding of the thermal situation and sophisticated measurement methods to determine... Read More
Tolerancing is a subject that is often overlooked, or not fully addressed, in the design of illumination optics. Tolerancing methods are well developed and understood in the lens design and imaging system design fields, but tolerancing of illumination optics is much less well developed. Optical design and optimization software tools can allow the designer to make new and exciting designs, but it is possible that the design may not be economical to manufacture due to the sensitivity of the design to variations in the manufacturing process. New tolerance analysis tools in optical design and analysis software allows designers and engineers to evaluate the effect of manufacturing variations and how it will affect the overall performance of the system. This makes it possible to see if a design is truly practical and economical. We will look at the tolerancing methodology as well as some tolerancing examples in this paper.
LED technology offers new spectral and radiative features for lighting applications for which conventional quality criterias and measures (introduced in 1974 and before) are not sufficient. At the same time the knowledge about light impacts on human and about human needs has increased significantly over the last two decades. The workshop demonstrates the most important features regarding visual perception and non-visual effects which has to be respected for LED applications: – Spectral quality (colour rendering, fidelity, and preference; whiteness, Colour mixing white – white and black body line, etc.) – Glare, discomfort, light pressure – Health effects (sleep quality, alertness, etc.; melanopic factor, amel,v, light dose) – light directness and shadowness (radiation field). Recommendations will be given to quantify these effects. Lessons learned: Awareness for the critical features of LED applications will be increased, and (some new) quality criterias (measures) with value ranges will be given. Proposals for solutions will be made.
Beside to display technology, OLED also has unlikely potential for lighting applications. Where extremely thin, flexible or transparent light sources are desired, OLED can exploit its potential as a supplement to the LED. The presentation will give a general introduction to the OLED technology and an overview of the market. Furthermore it will focus on current research topics and potential application areas. The improvement of flexible OLED is currently the focus of worldwide research activities. Thin substrates of primarily barrier-coated polymer films, but also metal foils or ultra-thin glass, were tested for use in OLED production and have advantages and disadvantages. OLED prototypes on polymer substrates as well as ultra-bright glass were realized by Fraunhofer FEP. The main development areas are the improvement of device stability and brightness. This includes intensive work on encapsulation as well as the development of stacked OLED architectures on flexible substrates. In future, the focus will be on the development of integration solutions in functional devices and surfaces using established technologies. Fraunhofer FEP works on processes along the entire value chain to produce flexible OLEDs in both, sheet-to-sheet and roll-to-roll processes.
Peter Duine will cover the power of partnership in connected lighting. His keynote will focus on providing clear example of why partnership and standards are so important in this new digital era. He will describe killer Apps for connected Indoor lighting (HiBay and Office) and Outdoor lighting. Philips has developed a platform of digital drivers with SR technology where SR stands for Sensor Ready. The two wires of the interface provide power to sensors that can be mounted in or on the fixture, and the data exchange between the driver is based on DALI with already two industry consortiums picking up the effort to standardize these data models (ANSI and DiiA). Although the killer APPs for connected lighting are still very basic (energy saving and asset management) it is expected that based on these standards more partner companies will develop advanced use cases and will grow the application space of connected lighting.
Silicone optics have become quite well adopted in high end LED lamps & luminaires lighting applications, such as, e.g., automotive headlamps, outdoor streets, roadways and stadium as well as retails. Dow Silicones have largely contributed by demonstrating the benefits of silicones optics from various perspectives, such as, e.g., resistance to high heat and lumen fluxes, stability against UV radiation, high resistance against scratch and impact, good compression set, enhanced optics and free form lenses design capabilities, and opportunities to optimize manufacturing processes of optics at large volume industrial scales. However, an area that was less explored until now was the possibilities to combine benefits of both thermoplastics and silicones in the design of optics for applications in LED lighting. Although over-molding of Liquid-Silicone-Rubber (LSR) on thermoplastics and composites, glass or metallic substrates is not new, Dow Silicones and Gaggione have decided to bring forwards this technology to the world of optics. The integration of silicone optics with thermosplatics enables to bring multiple functionalities into a single component with optimal performances: high grades optics – including accurate surface features, ingress protection (IP), impact protection (IK), rigidity, dimensional stability, and ease of assembling into LED lighting modules. The work presented here will describe how... Read More
Recent trends in the LED industry include higher power LED packages, novel architectural form factors and smart & connected lighting. All these trends have one thing in common: more electrical power being packaged within increasingly slim and lightweight form factors. The resulting increase in power density and inclusion of temperature-sensitive electronics drives the need for innovative thermal management solutions to ensure maximum performance and long life. Flexible graphite is being used extensively to remove heat from LED circuit boards, drivers, and other “smart lighting” components, and will play a leading role in the thermal management of the next generation of LED Luminaires. Flexible graphite’s key properties include high in-plane thermal conductivity, low thermal contact resistance, light weight, flexibility, compressibility, cost effectiveness, infinite duty life, and sustainable cradle to grave characteristics. Due to its unique structure and properties, flexible graphite can be used as a heat spreader, heat shield or thermal interface material. Case studies for specific end uses will be described. A strong emphasis on cooling drivers in exterior lighting fixtures will show how to design systems to effectively remove heat and improve the longevity of LED system components thus, reducing maintenance and warranty costs. A technology roadmap will clearly... Read More
Having emergency lighting, just to meet code and just to code, is not enough. The world is starting to take notice of the importance of emergency lighting. The traditional rudimentary procedures to test and report emergency lighting diagnostics is manual, burdensome and inefficient. But no more. The days of maintenance or operations personnel walking the facilities, manually pressing a button to ensure the proper function of emergency lighting is already replaced with advanced luminaires. Now there is the opportunity, as with many other devices, to become part of a larger, connected IoT ecosystem providing users with streamlined testing and automatic reporting. More importantly, there is an opportunity to improve functionality in emergency lighting to ensure greater safety and security in the rare times that we need to use the system. Starting at the emergency luminaire, advanced processing features are necessary to enable monthly and annual diagnostic tests and reports, to various specifications. Couple that with wireless (BLE Mesh) or wired (DALI) systems, or even a combination of both, allows you to log those reports in your central database. Connecting to a network also allows the end user to schedule tests in a time that will not interfere with daily operations... Read More
We provide an update on laser light technology including luminous flux, luminance, lumen density, efficacy, and color quality. LaserLight has demonstrated record breaking results with 750 lumens emitted from a 300 micron diameter window, an order of magnitude higher than other solid state light sources. We describe recent, innovative laser light modules that produce highly directional and precisely shaped spotlight illumination. Novel laser light systems are described including dynamic modulation and waveguide delivered lighting. Actual results from implementations in lighting applications are illustrated. Lastly, we introduce new results in ultra-fast modulation of laser light for potential IoT & LiFi applications. This presentation will address: • Introduction to laser light technology (laser diode pumped phosphor technology). • Fundamental performance differences for laser light versus LED & legacy light sources including: lack of droop, order of magnitude higher luminance & lumen density, 1o beam angle, and efficient waveguide delivery. • Current applications in automotive, display, entertainment and other specialty lighting • Discuss novel IoT and LiFi potential for laser light sources.
The LED industry is developing and posing new challenges to manufacturers of LEDs, PCBs, thermal interfaces and cooling systems. In particular, PCB manufacturers for LED applications solve conflicting tasks: 1. dielectric thermal resistance reduction – increase of the breakdown voltages; 2. placement of LEDs, current supply and control circuit in a single module with limited area – ensuring a uniform luminous flux and using standard lenses. In fact, these points send developers to the laminate material (substrate) that combines the advantages of ceramics in terms of thermal management and high electrical strength, and FR4, which provides the flexibility of transition between layers at low price. RUSALOX is systematically conducting R&D works and seeking for new engineering solutions based on al oxide material. In 2017 a major R&D project was launched and for the first quarter of 2018 highly qualified, al oxide production experienced team has achieved the following results in serial production: 1 high thermal conductivity of the dielectric of 12-24 W/mK depending on dielectric thickness; 2 breakdown voltages up to 7000 V DC; 3 double-sided PCBs with PTH with diameter from 0,4 mm These results enable to design high-power LED modules with high-densed of LEDs (so called “High Power... Read More
As part of a funding project, the Institute of Electronics at NTB has developed an intelligent luminaire system that is capable of organising itself, controlling brightness and optimising power consumption using presence detectors and Visible Light Communication (VLC). The LEDs allow information to be modulated into visible light without additional electronics. The information is received via an inte-grated photodiode. Also for the receiver only little additional hardware is necessary. With this proce-dure a communication without radio and without special modules can be realized. As part of this project, a system with a range of 20 metres was developed.
LED modules providing tuneable white is the core technology for human centric lighting. It is state of the art that such LED modules consists of two types of LEDs with different color temperatures. These two groups of LEDs are supplied independently and thus a variable color temperature based on the mixtures of the emitted light of the two types of LEDs is resulting. For many applications a flexible circuit tape offers interesting advantages when used for human centric lighting: Such a LED-tape can be easily customized to any required length and can be bended within a large extend. The limitations of this technology are linked with the layout of the flexible circuit tape and the output characteristics of an external controller providing constant supply voltage for the LEDs. We are now presenting a new technology how to design and operate a flexible circuit tape for tunable white applications: Core of our design is that we are suppling single LEDs by an inductive coupling which is a part of the flexible circuit tape design. By adjusting the frequency of the power line we can control the emitted light of such a single LED. Thus, it is possible to have different lumen... Read More
Moderator: Dr. Perez Panelists: Dr. Stephen Archer Mason, Optometrist and Managing Director, Sustainable Eye Health Pty Mag. Wilfried Pohl, R&D Manager, Bartenbach Francesc Jordana, R&D Lighting Manager, Simon Wellness real estate, healthy housing, is an emerging trend in the built environment. In this workshop, we will discuss the different lighting requirements in building standards, principally BREEAM, LEED, and WELL, their crosswalks, and their interaction with human well-being, wellness, and ultimately health, with an emphasis in the circadian feature of the WELL Building Standard. Daylight is recognized in these models as a key factor in the architectural spaces, not only in terms of energy savings, but also and in wellness and well-being benefits for the building occupants. When daylight is poor, or not available, electric/artificial light becomes critical to either supplement daylight, or to fulfill the whole lighting requirements in the built environment. Beyond classical requirements such as glare and color quality, WELL introduces a unique specific mandatory feature for circadian design, feature 54. This feature brings up a challenging dichotomy for lighting designers and manufacturers: glare avoidance and visual comfort strategies try to avoid high luminance and direct eye exposure to light sources (dark-lighting), but melanopic stimulus at the eye... Read More
Owing to its exceptional optical and electrical properties, indium-tin oxide (ITO) is nowadays the material of choice for providing transparent electronic conduction in nearly all flat panel displays used in TV screens, laptop computers and mobile phones, regardless whether they are based on liquid-crystal display (LCD) or organic light-emitting diode (OLED) technologies. However, emerging applications of wearable electronics and augmented reality have very demanding technical requirements in terms of brightness, response time, contrast ratio, energy efficiency and advanced packaging density which cannot be met by these display technologies. The new micro-LED technology is currently considered as one of the most promising solutions that would offer the levels of performance required by next generation display market applications. Whether these displays have to be fabricated by hybridization of micro-LED arrays with the CMOS active matrix using the flip-chip technology, or by monolithic hybrid integration, successful realization of micro-LED based devices requires front end semiconductor manufacturing approaches and handling standards for the thin film processes involved. For the transparent conductive ITO layers this means an absolute control of particles and defects, single wafer traceability, and compatibility with standard 12” manufacturing technology. Moreover, improved heating uniformity is required, especially for achieving uniformly high optical... Read More
Today’s novel, new LEDs spectrums and CCT tunable LEDs require more complex methods for characterizing “quality of light.” Too many lighting specifiers today are struggling with a supply chain using legacy specification methodologies derived from over a century of conventional bulb technology. As we close the door on traditional bulb use, new LED lighting technology offers beautiful options which require our industry to leave behind today’s lingering, outdated standards such as ANSI bins and CRIs. Tunable light sources enable the user to create unique environments to match the season or even the time of day. Innovative phosphor blends, pumped by violet, blue, and cyan, are creating new spectrums never seen before, where whites are whiter, colors are richer, and efficacies are saving even more energy. Chromaticity targets can move freely above or below the BBL, and spectrums can be tuned to match our growing understanding of human photobiological needs as well as the needs of the various plants we consume. Merchandise in retail stores can look even more appealing, pedestrians can feel safer, patients can heal faster, and workers can be more productive. There are challenges in how to specify these innovative new LED sources. This talk will explore some... Read More
As consumers become more sensitive to the quality lighting, a new metric is appearing: flickering. We’ll take a look at the flickering of conventional direct AC (driver on board) and DC driver systems for general lighting applications. Besides flickering, size and weight of drivers are increasingly important to support lighting designers achieving slim and light luminary designs. In the past, direct AC drivers could support a light design, but compromised on flickering. DC drivers can help to reduce flickering, but are quite heavy and bulky. With new integrated drivers, the advantages of flicker-free and slim and light drivers can be combined in one products. This may allow designers greater freedom in design, while maintaining a high level of light quality.
Professional LED lighting is overcoming today many shortcomings of the first LED lighting systems. In the early days of LED lighting the focus was predominately on outperforming conventional bulb and tubes in term of power consumption, rather than on light quality. Since then the request for higher lighting quality has been rising step by step. Nowadays the features of high quality lighting includes not only deep dimming and flicker free light but also low standby power or full spectrum color control. The combination of these features is adding complexity at large scale to the LED lighting system and the LED driver electronics as well. Simultaneously also regulatory requirements of LED lighting increased, setting limits for Power Factor or the lately introduced California Title 24 reduced flicker operation definition. On top of this, the variety of LED modules is exploding, demanding driver with wider window of operations. If this alone wouldn´t be challenging enough of course next year’s generation LED driver need to be less costly than previous one. Recent studies and designs of leading lighting companies respond to these challenges with resonant topologies LED driver, which can be effectively designed from 40Watt upwards. The paper will focus on some key performance attributes of... Read More
In recent decades, the use of artificial illumination has rapidly increased, transforming nocturnal environments worldwide. Inappropriate and extensive use of artificial illumination results in light pollution: an increase in nocturnal light above natural levels and a disruption of natural light cycles. Light/dark cycles have been stable over geological and evolutionary timescales, and most organisms rely on light as information source to regulate internal processes through circadian clocks. Furthermore, many organisms evolved to be night-active, to perform their activities in what are naturally dark and dim night environments. Today, as almost a quarter of Earth’s land experience light pollution, this novel, pervasive and widespread environmental change raises concerns about potentially adverse effects on organisms and processes in nocturnally-lit ecosystems. As mounting evidence shows that artificial light at night affects microorganisms, plants, animals and humans, light pollution is increasingly recognized as a global concern and a threat to biodiversity. In my talk I will give an overview of the recent research into ecological effects of artificial light at night with focus on insects, and discuss how various lethal and sub-lethal impacts of artificial illumination can increase environmental pressure on insect populations and threaten their survival. Alarming rates of declines in insect populations... Read More
Design of luminaires is becoming easier due to the use of standard modules. Still the design of optics and the mainly performance related parameters are considered the challenge. But is that all? The world is changing at a rapid pace. We saw the introduction of several new standards and pieces of legislation in 2016/2017. In 2018 the developments will continue to go at a fast pace. Not only will we see a new Energy related products regulation, the so called “one lighting regulation” but also other directives and regulations are coming into force or are already in force (by September). Many of those are not the standards requirements that we had to deal with till now. The new privacy directive will have impact also on product design and for example the cybersecurity regulation will also have a serious impact on lighting design. The implications on product design and approbation procedures are serious. Many companies are only focusing on the current and very basic directive. Only few companies are already looking at the implications that they have to deal with future applications. The main challenge for the industry is how to create modules that will allow for easy product design. Helping those smaller niche... Read More
LEDs paved the way to serve applications with custom designed spectra. From fashion applications it is evident that light sources with same correlated color temperature do produce distinctly different visual appearance. Now players in the theatre and entertainment domain started to embraced LED solutions with multi-spectral sources. As a result of this the days for lighting gels are numbered. One reasons for this quick transition lies in the fact that combinations of LEDs succeed to provide excellent color reproduction properties while maintaining a large color gamut. For theatre lighting it is key that visual appearance of the scene fits the intended emotional content. To ensure that subtle changes can be expressed more and more solutions enriched the spectrum by adding wide band emission spectra (white or lime) to small band chromatic colors. Today we find theatre lights with up to 8 different types of LEDs in it. This guarantees that also the subtlest variations in hue and chroma can be reproduced. Next to the obvious needs to provide a large scope of colors the multi spectral approach bears the opportunity to optimize the spectra according a variety of strategies. Spectra can be selected to stimulate health effects, support biological rhythms... Read More
The EU spends a lot of effort on reducing overall energy consumption to achieve the climate goals of the Kyoto Agreement and to contribute to environmental sustainability. One measure to achieve this worthy goal is the regulation of luminous efficiency for various lighting sources. Current regulations already allow an exception for stage-, theatrical- and studio light sources, because of their unusual quality demands and singles out spectral distribution as a crucial criterion. There is an ongoing attempt to condense and simplify the three EU-directives relating to “EcoDesign” so that they can be replaced by a single directive that should come into force by September 2020. The draft presented at the EcoDesign Consultation Forum in December 2017 no longer highlighted stage lighting as an exception. According to correspondence with the responsible policy officer of the European Commission, their assumption was that “there could be scope for the exemptions for the theatre sector to be removed”. The public review finished in January 2018 gave rise to comments from various interest groups, theatrical associations, lighting designers, end-users, manufacturer associations (such as PLASA – Professional Light and Sound Association, UK; VPLT -Der Verband für Medien und Veranstaltungstechnik e.V., Germany; and ALD – The Association... Read More
Among other things, the evaluation of methods and systems for encapsulating LED modules led to the question of the expected service life. Information from the manufacturers of the chemical components of a potting system were imprecise and hardly meaningful. The aim of the work is to investigate different systems and to characterize them with methods that are established in LED technology. The central question is whether a potted LED module can achieve a lifetime under realistic conditions, which is considered to be common for LED modules. A test based on the LM-80 evaluation will show whether acceptable lifetimes are achieved and whether it seems realistic to use extrapolation such as TM-21. For evaluation, five potting systems were selected. Standard LED modules were glued into a U-profile. The profile has been designed so that the temperature at the Tc point of the LED module settles at 95 ° C. Five sample groups were potted with the different systems. A sample group was not potted to have a reference. All LED modules were measured before treatment. With this measurement, the direct influence of the encapsulation can be measured. The measurement of all modules after completion of the encapsulation forms the value set... Read More
This paper discusses how spectral tuning and LED source size can be used across all sports lighting applications. In years past, the retrofit lamp industry witnessed the revolution of indoor lighting migrating from low CRI bulbs to now 90 CRI bulbs due to advancements in die and phosphor efficiency as well as color rendering technology. The sports lighting industry is experiencing a similar phenomenon; however, sports lighting have an added complexity where high end sports lighting not only serve a human audience , but also a silicon detector; hence, requiring TLCI values greater than 90, in addition to fulfilling CCT/CRI specifications on lighting. The high TLCI values can be achieve by intelligently color tuning with phosphors. This paper shall explain the vast field of sports lighting requirements from the lights at a primary school’s gymnasium to the local neighborhood sports field to professional stadiums where championship games such as the Super Bowl and World Cup are held and televised. The added dimension of televising places a requirement on TLCI. We shall analyze the differing color perceptions when broadcasting cameras film under low or high TLCI lighting. In addition, we shall examine the new sports lighting specifications from China as well... Read More
Together with high energy saving potentials, LED reliability is considered as one of the key advantages of this technology for artificial lighting . The promise of lighting systems with high reliability leads to various advantages such as lower maintenance needs, long term cost savings and a reduction of the impact of production on the environment. With the growing maturity of LEDs and the increase control over their spectrum, new applications focusing on the effect of light beyond its conventional illumination function are emerging . As a result, the quantity of LED based lighting solutions for horticulture, agriculture or wildlife care is constantly increasing . In a wider scale, the impact of light on humans, including its impact on the circadian rhythms, is more and more considered and is foreseen as one of the major trend for indoor lighting in the coming years . Those “beyond lighting” applications require the implementation of new metrics (e.g Cs/CLA or ML for circadian lighting). Reliability is defined as the ability of a component or system to fulfill its required functions in a certain environment for a specific period. Therefore, for these applications, the lighting system function is not only illumination but can also be... Read More
Through a patent-pending planar micro-tracking technology, Insolight is developing an innovative dynamic luminaire technology, which allows to redirect light from a LED flat panel without tilt. The technology is based on a combination of different technology blocks: a custom optical layer, a microtracking system and a LED module. By slightly shifting in the plane the LEDs compared to the optics, the microtracking allows to control the output light beam and its direction. The tilt precision and the pan of the light beam can be remotely changed via a smartphone or another control system (DALI/DMX). The optical system can be customized and optimized for any photometric curves, from a narrow beam to an asymmetric curve.
LED products quality assurance has been discussed a lot in the last several years. Many standards and system solutions were developed to control the lighting product quality. Lamp manufacturers and end-users usually focused on better product performance, efficacy and standard compliance. However recently a growing need for dependable and practical on-site LED lighting verification is observed. This is caused both by the new standards for lighting installations as well as newly proposed metrics which help to verify the lighting installations quality. Traditional approach for on-site lighting audits was focused on photometric quantities like illuminance [lx] or luminance [cd/m^2]. Due to the fact that our knowledge about the influence of light onto the human body is increasing and the technology is able to support the effective use of lighting to increase a well-being of people there is a need for tools and complete solutions to verify lighting quality. This paper will provide a detailed description of a novel solution which is connecting the CAD lighting design software with the on-site measurement supported by new technology illuminance spectroradiometers able to handle measurement procedure to verify and report lighting levels and other quality measures using CAD plans as a reference and reporting illuminance level... Read More
“Securing food for a growing world population, loss of fertile soils by urbanization, erosion and desertification and change of precipitation patterns due to climate change and negative impacts of conventional agriculture – these are the factors making it inevitable to develop new concepts for a resource efficient food production. Moreover urban horticultural systems can contribute to enhance the supply of urban inhabitants with high quality products. Especially fresh vegetables as tomatoes or cucumbers are grown hydroponically in protected horticultures already in significant rates where soil-independent water-based systems are used to ensure the supply of much of the vegetables. The site conditions are only linked to light, water, heat and nutrient availability. These four factors can be found without any difficulties in urban areas. By integrating food production into new or existing building technologies (inFARMING®) synergies of the greenhouse and the original building can be used effectively. As part of our work we will present new results of demonstration plant experiments for intelligent grow light systems. Regarding new requirements in indoor farming applications growth conditions of plants concerning concentrations of the active ingredients can be regulated among others by adapting the light spectrum. The technology is demonstrated by the example of lovage... Read More
“Among the many advantages of LEDs is their long lifetime. Lifetimes of 50 000h and more are expected and claimed which is equivalent to more than 10 years if operated for 12h per day. But how can one ensure or predict such a long time period? The LM80 and TM21 are common standard requirements and methods to extrapolate the lifetime of LEDs for different forward current and temperature conditions. But seeing no degradation in the first 6000h hours does not guarantee that this trend will continue. How can one understand the behavior of LEDs over the complete lifetime without testing for 50 000h? There are proven and well established methods of robustness and reliability testing which require a destructive testing of the LED under well-chosen overstress conditions in order to accelerate the aging of the LED in order to determine the typical aging behavior under lab conditions. These robustness tests are necessary to understand the failure mechanisms of the different parts of the LED and allow a detailed modelling of behavior under application conditions. The lifetime of LEDs is not only determined by the degradation of the luminous flux but also by catastrophic failures of interconnections due to thermos mechanical... Read More
EPIC Workshop on Lighting and Laser Projection for the Entertainment Industry is meant to create a forum of discussion and collaboration on laser displays and related technologies. Presentations from key companies in the field will cover the full value chains of laser displays and other lighting technologies, from components to system integrators: Lasers and light sources manufacturers (Visible lasers, LEDs, Solid-state light sources, Phosphors, Fluorescent materials, Wavelength conversion materials, Optoelectronic materials), optical components for projection (Spatial light modulators, High-speed scanners, MEMS, Active-matrix integration, Projection components, Display drivers and interfaces), imaging and projection novel technologies (3D imaging, Holography, Laser backlight unit, Novel and emerging display and lighting technologies, TOF, Pattering, Stereo-vision, Image quality evaluation, Color reproduction, Color management, Color appearance), all the way to system integrators for the main market driven applications (LCD TV, 3D-TV, Projector, HMD and HUD, Lighting technologies, Touch technologies, Laser show, Power saving techniques, Biomedical imaging, Industrial imaging, Automotive Lighting). In addition, issues such as laser safety, regulations, component price and ramp up to production for innovative concepts will also be discussed. PROGRAM 10:30 – 10:35 Opening of the event – Jose Pozo, CTO, EPIC – European Photonics Industry Consortium 10:35 – 10:55 Keynote presentation by Werner... Read More
Over the last few years, the power density of white LEDs has increased dramatically. Whilst there are large efforts to optimize the thermal management and thus the temperature stability of the LEDs, less attention is paid to the temperature of the secondary optics. A higher temperature stability of the LED and the primary optic might result in conditions, where the temperature of the secondary optic exceeds its allowed working temperature. This is of particular interest if the secondary optic is made out of a polymer. Note, that the heat distortion temperature (HDT) of the commonly-used materials for secondary optics such as polymethyl methacrylate (PMMA) and polycarbonate (PC) is at 95 °C and 122 °C, respectively (both values according to ISO 75 at 1.8 MPa). If the secondary optic is permanently operated above these temperatures, its optical properties might change. In a worst case scenario, even a deformation is possible. While glass optics are certainly an alternative, polymer optics are preferred by lighting manufacturers due to their cost and weight advantages. It is thus of importance to have an exact knowledge on the temperature profile within the secondary optic. In this work, the temperature profile of secondary optics in combination with... Read More
With the global trend of increasing urban population, there is therefore an observably growing demand for fresh, high quality, flavor and nutrition-rich food to be supported for the cities. The main market drivers of Greenhouse, Hydroponic and Aeroponic food production are increasing production costs, challenging weather- and climatic conditions and increasing power prices. While the natural lighting is considered to be the most energy efficient for growing plants, for the increased yield, it is often financially beneficial to apply supplementary lighting; especially during seasons with lower Daily Light Integral (DLI). Then the goods sell prices are higher and in some instances, the production is to be suppressed for this timeframe due to inappropriate light conditions. This paper focuses on the estimation of DLI per region and per season in the EMEA region, the lighting requirements of certain plants and introduces a method for calculating the peak Return on Investment hence. The aim is to compare fixed Photosynthetic Photon Flux (PPF) systems with adaptive spectral- and intensity controlled solutions from a financial point of view and briefly introduce core technologies available for the latter.
The LED industry has been successful in providing retrofit solutions for most incumbent light sources. This has led to a rapid ledification of many lighting segments and thus contributed to very significant energy savings around the globe. One of the remaining challenges is to retrofit fluorescent tubes, which, once achieved, will bring, besides energy savings, a very important contribution to the eradication of mercury from the environment, one of the goals of the RoHS regulation. The origin of this challenge is the huge number of different ballasts installed in the field to operate fluorescent tubes. This not only leads to differences between retrofit projects, but even more challenging is the fact that as a result of regular maintenance there can be substantial differences between the ballasts found within one and the same retrofit project. Over the last 5 years we have developed and brought to the EU market a cost effective universal solution with unsurpassed ballast compatibility, which offers to installers the user friendly universal retrofit solution they are looking for. The heart of this solution is to use the ballast, be it magnetic or electronic, as the supply of energy to the LED’s and to configure LED’s and LED tube electronics accordingly. We... Read More
Meanwhile, there are some measuring devices to measure light flicker because it has been recognized that fluctuations in the brightness of artificial illumination have a negative effect on the nervous system of humans and other beings. Despite the years after recognizing the need to measure this, there is still no agreement on the measurement method. The only thing that is clear is that a simple amplitude measurement is not enough, but that an analysis and a weighted evaluation of the individual frequencies over a wide range is the right approach. The most widespread method according to IES: RP-16-10 with %flicker (pure amplitude ratios) and flicker index (pure area ratios) is the least suitable because two values whose combination is not defined are not communicable and also frequencies not considered at all. Although IEEE 1789 only considers the main frequency, the weighting function contains a physiologically unexplained discontinuity. In addition, the limits are so sharp that even the low flicker of the European light bulb is considered dangerous. The procedure according to California Energy Commission Title 24 JA10 fails due to the lack of weighting of contained frequencies, which is why a highly noticeable flicker below 25 Hz is considered “low flicker”. The... Read More
Light sources, which are temporally modulated in emitted radiation, may induce several direct perceivably artefacts to human beings, for instance, visual unsteadiness in intensity or spectrum of light (flicker effect), in motion (stroboscopic effect) or in perceived shape or spatial position of objects (phantom array effect). Several experiments with LED light sources have been conducted recently, within which visibility thresholds for flicker and stroboscopic effects were derived. Studies over the past 60 years have clearly shown that three factors (related to the luminaire, subject and environment) mainly contribute to the occurrence of visible as well as non- visible effects of temporally modulated lights. Today there is evidence, that the amount, frequency and modulation depth of the emitted light, the size of the light emitting surface, the spatial position of the luminaire within the field of view, the age and arousal level of the exposed subject, and fast moving objects (e.g., at industrial workplaces, in sports, on roadways), fast eye movements (e.g., during proof-reading) or fast head movements play a crucial role. Published methods and metrics and design recommen- dations from the International Commission on Illumination and the German Electrical & Electronic Industry take perceivable effects of temporally modulated illumination of... Read More
With the advent of digitalisation and connectivity in a sector such as lighting, new paradigms for interoperability between services are generated, which facilitate and improve the citizen experience. The street lighting network, because of its privileged location, can play a determining role. The street lighting network is visible in the most remote locations and covers almost every inhabited area worldwide. Its privileged position close to residents and thanks to its connection to the power grid not only provides the essential street lighting service, but also acts as the ideal platform from which to support many others. This is a major challenge given that this network must have a high availability ratio and provide a robust service, for which it is necessary to carry out an adequate deployment. In return, it allows us to have interoperability between the different urban services, to be more efficient in the management of them and to provide them to the citizen with higher quality. Water supply is one of the most important urban services in a city. Its proper management is a guarantee of water quality, of the sustainability of the service through the optimization of resources as well as a correct quantification and valuation of the... Read More
The workshop covers the basics of test and measurements of solid-state lighting (SSL) products and is suitable for beginners as well as experts in the field. To provide the same level of knowledge for all participants, an introduction to SSL metrology and the relevant standards such as the first international SSL standard CIE S025 are given in the beginning. Basic quantities and principles in photometry and colorimetry will be defined and proper equipment for their determination will be presented. Important aspects for color characterization, such as correlated color temperature (CCT) and color rendering index (CRI) will be included as well. Participants will learn how to evaluate the optical performance of LEDs as basic components of SSL sources. Aftewards, the most essential measurement procedures and used instrumentation in SSL measurements will be introduced with focus on goniophotometers and integrating spheres. Goniophotometric measurements provide details of the radiation patterns for different light sources and when correctly integrated, the total luminous flux is obtained. Furthermore, in combination with a spectroradiometer, goniophotometric measurements can provide detailed analysis of the spatial distribution of all photometric and colorimetric quantities such as CCT and CRI at the same time. For fast measurements of the luminous flux an... Read More
„Light is not visible, light makes visible”, this also means that the room should be lit and the luminaires step into the background. In modern lighting solutions the luminaires are often no longer visible as they are integrated into the architecture, e.g. combined with acoustic absorbers or cooling ceilings. LED technology makes it possible to use very small optics, but at the same time, all other components of the luminaires must also be smaller to exploit this miniaturization potential. More efficient LEDs mean less heat and consequently smaller heatsinks. But reducing the size of the LED-driver leads in general to a deterioration in the quality of the light, i.e. flicker. The size of the luminaire is meanwhile bound to the size and quality of the driver (electronics circuit), thus the driver becomes a key component of the luminaire. Smaller lights are also often associated with human centric lighting (HCL). This increases the demand on the requirements for the driver, which is difficult to solve with miniaturization. A LED driver is normally composed of three parts, an ACDC converter ensuring good mains performance (PF and THD), a bulk capacitor storing the 50/100 Hz energy from the mains and a DCDC converter which... Read More
LED-technology is being utilized in more and more areas. Tunnel lighting for example is an extensive field for the application of LED-technology especially in countries with alpine terrain, like Austria and Switzerland. Good reliability and a sustainable energy balance are only a few arguments for the replacement of traditional lighting systems. Therefore, increasingly more tunnels are equipped with new LED-luminaires, for example the Pfänder-Tunnel and the Arlberg-Tunnel, which are both extremely important for the region around Bregenz. When designing optical systems for tunnel luminaires many criteria must be kept in mind: a lighting design must reach requirements regarding homogeneity, luminance and threshold increment, and still handle the challenging environmental conditions that are found in tunnels. With the increase of LED efficiency also luminaire efficiency is an important benchmark for the assignment of most public contracts, especially since this value is understood well by non-lighting related professionals. Minimum values are now even defined in public regulations like the Austrian regulation PlaPB800.562.1000 of ASFINAG (the Austrian infrastructure corporation). Unfortunately, the focus on this specific value easily leads to wrong conclusions regarding energy saving as it only considers a single luminaire instead of the whole lighting system. Clearly luminaires without any specific optical... Read More