Lighting/Illumination Forum 2014

CONVENED AND MODERATED BY PAUL O’SHEA

The United Nations declared 2015 as the International Year of Light. The LED is a major invention that contributed to significant improvement to energy efficiency. Researchers for the blue LED also recently won a Nobel prize. For lighting and illumination the LED has paved the way to many, very significant inventions, but we haven’t seen the end of these advancements.

Electronic Products : What are the near-term trends for lighting? Any trends stand-out such as smart homes/buildings? What is needed for the trend to be successful?

Marc Dyble (Product Marketing Manager, Solid State Lighting group, OSRAM Opto Semiconductors )

The next trend is human-centric or “I-centric” lighting products, creating personalized lighting spaces through the use of smart lamps, which merge lighting and information technology together. As an always-on connected node, these lighting fixtures and lamps will not only provide dimming and color tuning to control color fidelity, they will soon integrate sensors to provide lighting that communicates and interacts with both the environment around it and the users that it serves, giving awareness of your surrounding environment. Why have only one smoke alarm or motion sensor in a room when every light source can become a multi-functional device. Sensor technologies could range from sampling airborne particulates such as smoke to monitoring CO₂ or humidity levels. In a retail environment, lighting could facilitate indoor positioning systems for wayfinding and provide high speed data transfer to your smart phone from the light source above you using light as a communication channel.  This system could be fed via a DC (direct current) low voltage power distribution, eliminating the need for costly high voltage cabling and conversion losses.

Another trend is to use light for light therapy and bio-systems (e.g. circadian entrainment, wound healing, horticultural applications) to improve our sense of well being. Promoting human centric lighting and mimicking light natural sources, such as a sunset, could be accomplished through multi-channel light sources.

In order for these trends to be successful, the LED and driver topology needs to be adopted and optimized together as a system. The question is, is it best to optimize for system cost or system efficacy? Should the use of a standard driver to standardize the cost of a solution weigh more heavily than an optimized system incorporating a custom driver at a different voltage? For the future implementation of integrated, connected and smart lighting systems, adoption and integration is necessary while at the same time managing costs.

Paul Scheidt: (Leader of product marketing, LED Components, Cree)

The lighting industry has made great progress in providing tangible value to customers and end users, including quick payback, low total cost of ownership, improved performance and high-quality illumination, and we expect the demand for energy-efficient LED lighting will continue to grow over the next few years, driven by the increased in awareness of the benefits of LED.

For lighting designers, the next generation of lighting will address the increasing demand for solutions that produce higher light output, higher optical density and better heat dissipation with fewer LED placements. The result is even greater system cost reductions that can inspire new designs at attractive prices. The Cree SC5 Technology Platform, for example, enables Cree Extreme High-Power (XHP) LEDs, representing a monumental leap in efficacy, disrupting the market and providing designers with opportunities to create high-performing, high-reliability LED lighting in ways they never before imagined.

In commercial buildings, perhaps the biggest lighting trend is the growth of LED-integrated wireless lighting controls. Not only are new building codes across North America requiring the use of lighting controls in more spaces, but organizations are looking for ways to reduce operating expenses to improve the bottom line to fund investment in other areas of the organization. Lighting is one of the largest consumers of electricity in a commercial building and is a natural place for builders, developers, designers and engineers to explore options to improve efficiency.

Mark Vermeulen: (Product Manager, TE Connectivity)

The trend is clear- LED lighting is now growing faster than ever based on the continuous need for energy efficiency. LED’s manufacturers can do just that- provide an energy efficient solution in addition to increased energy savings. LED’s potentially offer more overall customer benefits than other lighting sources currently on the market today. The possibilities are endless with LED lighting as you have the capability to change the color temperature of the lighting application itself, via software. In buildings today, you can change the entire atmosphere of a room with the touch of a button or a form of motion, whether it’s dimming the lights or simply turning them on – you are now in control without causing any adverse effect on the life performance of the LED. The capability and flexibility to control the light source plays nicely into the idea of home automation.

Although there are a number of applications that play into home automation, the trend of driving energy efficiency throughout the home can be strongly impacted by lighting. In some buildings today and in the future you walk into the room- the lights will turn on and when you leave, they turn off. This not only allows for increased energy savings, but also helps extend the life of each LED throughout the building and your home.

At TE Connectivity, we plan to stay ahead of the market demand and continue to provide you with the lighting solutions you need to make your installation process smoother and our overall cost- friendlier.

Brett Shriver: (VP Sales and Marketing, Global Lighting Technologies)

Near term trends include the implementation of smart lighting controls within fixtures. These include ambient light sensors allowing a user to choose the level of illumination within a room instead of the level of illumination within the fixture as well as occupancy sensors to automatically turn fixtures off and on. This as well as the adoption of LEDs in mid and lower level cost point fixtures.

Electronic Products : What are the long-term trends? What’s holding them back from being used now?

Marc Dyble: Higher integration of drive electronics into the LED PCB, and not as a separate system, will be a long term trend to further shrink LED source sizes and reduce component count. We have already reached LED efficacies surpassing that of incumbent lighting sources, and although increased efficacy is always top of mind, and the race continues to stay ahead, we are now more cost driven than ever. Semiconductor process optimizations are constantly being evaluated to make products more cost effective, along with continuous cost downs on existing products to reach the mass market. This focus among industry players makes it difficult to integrate value add components, such as sensors, into LEDs packages or provide higher levels of system integration at a reasonable cost.

One potential hold on the industry today is the one thing meant to push quality LED products forward: Standards. While LM-80 and TM-21 help to substantiate claims of product performance and lifetime, LED product standards, such as size and shape of and LED, could block innovation and delay LED development. Outside of the Zhaga standard for the light emitting surface (LES) no standard currently exists for Chip-on-board LEDs (COBs). Just as most LED manufacturers have a 5630 package type, which is more or less a standard product due to high market penetration, no official standard exists dictating its dimensions.

Another example of this are Class A color light sources, which have been gauged to have high acceptability and naturalness among test subjects over high CRI products,  but whose chromaticity points fall outside the defined ANSI quadrangle color standard. As a result, lighting designers could not use these preferred light sources due to the limitation of the color standard.

Paul Scheidt : From the 2014 Nobel Prize for Physics, which was awarded to Cree colleague Shuji Nakamura along with two other scientists who helped invent the blue LED, to the United Nations, who decreed 2015 the International Year of Light, the world is seriously rethinking lighting for the first time in over a century. Companies like Cree are pushing the boundaries for LED lighting technology – from wireless lighting controls to dramatic improvements in energy efficiency and value.

LED technology continues to advance and addresses more lighting applications, introduce new form factors, integrate advanced functions and increase design flexibility. Customers will continue to see advantages in light quality, energy efficiency, up-front cost reductions and long-term maintenance savings. In fact, many LED lighting products are at, or close to, price parity with incumbent technologies. Today, LED lighting delivers improved value for customers, from better light quality to long lifetimes and energy and maintenance savings. Now, the cost of waiting to transition to LED lighting adds bottom line expenses to businesses, buildings and facilities every day.

Long-term LED lighting product innovations go beyond viewing light as only a source and point toward a world where LED lighting can enable new capabilities, designs and connectivity in building infrastructures. Furthering adoption at a rapid pace will require that our industry create truly uncompromising performance and simplicity.

Mark Vermeulen: The lighting market was originally driven by “traditional” lighting solutions, which require high voltage capabilities to be powered up. Since we’ve made the evolution to solid-state lighting solutions, we are now seeing devices such as laptops, tablets etc. can be supported by low voltage DC power.  Now that we are seeing more breakthroughs with LED’s, our next step should be to convert the high voltage currents into low direct currents but use the voltage directly from its source. With this conversion, we see a need for new connectivity solutions that could distribute the low voltage direct current reliably through a building. TE is actively working in the Solar, Lighting and power interconnect marketing to better understand and develop new products that would support this future trend.

Brett Shriver: Long-term, LEDs will transition from a replacement light source being fit into existing spaces where bulbs were once utilized, into the standard illumination device with fixtures designed around the strengths of this type of device. Currently this is being held back by two items. The first being fixture manufacturer and designers lack of knowledge with regards to the technology. This should improve quickly as the technology has been accepted for the future. The second item is consumers demand for a product with replaceable light sources. They have been left questioning reliability and life expectance of light sources after years of low quality replacement CFL and even some LED bulbs. As high quality LED devices continue to enter the market, and consumers learn of their reliability, the acceptance of the product will improve.

Electronic Products: What are the most important LED lighting specs for commercial use; for residential use? What do designers need to know about these specs for their designs to be successful?

Marc Dyble: Lighting specifications drive the adoption of LED technologies across multiple industries, but too often luminaire manufacturers struggle with dedicated LEDs slated for specific applications. Historically a certain LED would be targeted for a streetlight application, based on performance and product robustness, but another type would be recommended for a downlight. Today, many different LED types can be used in the same application. Mid-power LEDs have a good lm/$ ratio and are now used across many fixture types, such as high bays and downlights, which were once reserved for high power LEDs. It cannot be said that there is a dedicated LED for each application anymore.

Customers are using more standard products for design which can be a “drop-in” replacement from many manufactures. COB platforms make this very challenging as users cannot simply exchange LEDs as no standard mechanical sizes exist. As a result, a range of manufacturer specific COB holders exist.. Every light bulb supplier makes a standard screw cap to fit into a standard socket. Do we need to create the LED version of the Edison socket to keep everyone happy?

Paul Scheidt : LED lighting has evolved quickly with benefits like improved color rendering and quality, reduced maintenance and impressive payback, enabling unprecedented cost savings for business owners and consumers alike.

Energy efficiency is a primary consideration for commercial building specifiers and end users, as building energy codes have become highly restrictive, favoring the most-efficient options, such as control-integration. While specifiers are required to be cost-conscious, they understand that selecting a product with compromised features – such as poor light quality, functionality or efficacy – can potentially lead to more expenses and affect total system cost.

Light and color quality are also increasingly important to commercial building operators as the demand for consistent, high CRI illumination in applications, ranging from healthcare facilities to schools and offices, increases. Today’s LED luminaires produce a consistent light that can achieve a color rendering index (CRI) of greater than 90, and building tenants are taking notice of what’s now possible with LED lighting.

Innovations at the LED component level are helping manufacturers ensure color consistency and light quality. For example, the Cree XLamp MH-B LED featuring Cree’s EasyWhite technology and a small 5-mm light emitting surface provides many system benefits over arrays of mid-power LEDs, including tighter beam angles, simpler optics, a more traditional appearance and easier color consistency.

The rise of LED lighting in residential applications – in both breadth and price point – has reached a tipping point. Consumers and specifiers are seeing advantages in almost every aspect—from light quality and energy efficiency to quick payback periods. As these long term benefits are realized, the compromises of outdated lighting technology will become more apparent, accelerating motivation for quality LED lighting.

Mark Vermeulen: The LED industry is working very hard on standardizing the specifications on LED light sources. When you buy LEDs, you can often specify the color temperature, the color rendition and already get a high luminous efficiency. One pre-caution we tend to share with our installers is that there can be a difference in aging of LED’s. This difference is caused by the spread in production and how the LED is being used. It is important to ensure that the LED is properly mounted against a well-designed heat sink- the aging becomes remarkably different when the cooling of the LED is insufficient. My second piece of advice would be to carefully handle the LEDs. If the LED contacts are soldered, the LED needs to be heated to a high temperature. This is often done manually, but increases the risk of LED discoloring. TE’s LUMAWISE LED Holders eliminate the need for soldering; therefore prevent the change in performance of the LEDs. Our LUMAWISE LED holders also have a feature to attach the optics to the holder, so that the LED is always in the optimal position in the optics making it easier to enable similar color & performance.

Brett Shriver: In commercial use, the most important LED lighting specifications currently is lumens per watt and life.  Most commercial replacements and builds are currently being sold on power savings and energy cost reductions rather than esthetics or brightness. As such they are interested in ROI. For residential use however it seems the consumers are looking for color primarily as it is a new option in lighting for them. Many residential users were also unhappy with the color of the CFL bulbs and are now looking to LEDs in order to address this. In order to be successful with a new design you must take into account who your end customer is and what is going to drive them toward your product. Commercial is very different from residential.

Electronic Products: Compare some popular semiconductor technologies used in LED lighting such as sapphire, SiC, InGaN and GaN, and others. What long/short term observations do you have about their use for LEDs? What do engineers need to know about them before designing with them?

Marc Dyble: There are different advantages for each semiconductor type. For mass markets, there are advantages to our low and mid power sapphire based LEDs as we see these to be better positioned from a cost standpoint than our technology used for a high power LED (UX:3 or InGaN material type). These markets are highly cost sensitive therefore we offer the best cost/performance ratio as a result.

The main benefit of the new technology is the cost savings that arise from less expensive and larger substrates (up to 300 mm). This means that a larger number of chips can be fabricated more cost-effectively.

GaNonSi competes with existing technologies in which we are among the world  leaders. We decide on the introduction of new technologies always on the basis of cost, performance and quality. Since existing technologies are constantly being developed, it is possible that it may be a few years before GaNonSi is on a par with or superior to the best technologies in terms of efficiency and brightness. At present, we have identified greater potential for the existing technologies in our laboratories and production facilities so an immediate switch to silicon would appear to be premature. We have in-depth know-how in preparatory development work and a broad network involving international research institutes. We closely monitor all the latest trends and scrutinize the potential – from chip performance to cost-effective volume production. We will continue to focus on providing our customers with high-quality, high-power LEDs that offer optimized cost/performance ratios in all chip technologies.

Paul Scheidt : Different LED manufacturers will continue to build LEDs using different substrates. Cree is the only LED manufacturer that is able to build high-performing blue LEDs built on silicon carbide substrates. Silicon carbide substrates provide the industry’s best combination of high reliability, high performance and cost effectiveness.

Mark Vermeulen: Many of the semiconductor technologies are targeted at either allowing a higher operating temperature or at enabling easier heat extraction from the LED die (the actual heat source) to the outside. However, to know the actual temperature at which the LED runs and thus be able to determine the useful life, one must consider the entire thermal path. This is not only determined by the construction of the LED, but also by the quality of the heat sink, the properties of the thermal interface material and the quality of the LED holders. All of these contribute to optimal thermal management. It’s important to realize that the fixture should not only work well initially, but also over time so that the quality and properties of ALL materials is relevant in order to make a good lighting application. It’s essential to be able to do a good thermal path calculation to ensure that not just the LED runs below its specified maximum but that all parts in the thermal path can handle the thermal stress over time as well, or unexpected failures may be the result.