With the switch from short lived incandescent and fluorescent light sources to long lived LED light engines, the luminaire manufacturer’s responsibilities changed significantly. Now the luminaire manufacturer must also be an expert in electrical engineering, heat management, drivers, waveguides, and color science. The supply chains have also changed dramatically, and the rapid improvements in LED light sources means constant change for the luminaire manufacturer. This environment makes it difficult to find luminaire manufacturers who have the bandwidth to also add OLED luminaires to their portfolios. Despite this challenge, the OLED market is beginning to show growth as leading edge luminaire manufacturers and lighting designers see OLED as a way to differentiate themselves from the masses of LED fixture designers and take advantage of the faster design cycle and shorter supply chain.
Another obstacle to OLED adoption is the significant design paradigm shift that results from moving from extremely high brightness, concentrated point and line light sources like bulbs, tubes and LED light engines that must be hidden behind shades or optics or reflected off diffuse surfaces while hidden from direct view, to the diffuse area light source of OLEDs. With point sources, shades were a necessity and designers learned how to manage the high intensity concentrated light to create diffuse lighting fixtures or fixtures that used few light sources with multiple reflections to create fixtures with less concentrated glare-producing points of light. The techniques to manage and redirect LED light result in efficiency losses.
With OLED lighting panels the shade becomes obsolete as hiding the lighting panel negates the natural diffuse beauty of the light. Luminaires with many visible OLED lighting panels are preferred as they generate a beautiful diffuse high-color rendering space. This design approach eliminates the losses that are seen in LED or traditional fixtures; the overall efficiency is based simply on the OLED and the driver.
Technical challenges have also hindered the growth of the OLED luminaire market. The efficacy, size, color rendering index, and reliability of OLED lighting panels continues to improve and surpass the requirements for many applications. Beyond performance, the system architecture is evolving including low cost OLEDspecific drivers and building installation control of OLED luminaires. These solutions lag LED due simply to the size of the LED portfolio of products compared to OLED. These technical challenges will diminish over time, but currently they add to the resistance in market adoption.
Perhaps the biggest challenge to OLED market growth is cost. Like any new technology, cost is relatively high while the volumes remain small. Current OLED panels are estimated to be selling at over $100/klm. Cost projections over the next 5 years predict significant reductions in the $/klm for OLED lighting panels, with some of this reduction coming from volume growth, some from improvements in manufacturing and some from development of lower cost alternatives in the products and processes.
The Department of Energy predicts OLED panel costs will reach $10/klm by 20253. It is very important, however, to understand that $/klm is not the only measure of cost. It is not just the number of lumens but also how the lumens are used. In addition, the total cost of the luminaire includes heat sinks, optics, and product development time and costs. With OLED panels all of these costs are significantly lower. In addition, the low heat density of the OLED fixture allows for using less light closer to the user, increasing the use efficiency of the light. This, too, can result in lower total cost.
- OLED-Info website: http://www.oledinfo.com/ubi-sees-25-billion-oledl-ighting-market-2020-oled-lighting-may-eventually-get-cheaper-leds, May 15, 2015.
- U.S. Department of Energy, “Solid-State Lighting R&D Plan, May 2015.
- Lumiblade OLED Lighting, Lumiblade Insider, Issue 01/2015
- U.S. Department of Energy, “Manufacturing Roadmap: Solid State Lighting Research and Development, August 2014.