A Brief History of OLED Lighting
OLEDs are semiconductors that emit light when electricity is applied, but unlike LEDs, OLEDs are made from organic, carbon-based materials. Attracting investment across the globe, OLED is one of the most promising next-generation lighting technologies, despite its multiple challenges.
Very different from LED point sources, OLED lighting devices are thin panels that emit light across their surface area. OLEDs enable uniformly diffuse lighting panels, and can also be made transparent and flexible. OLEDs can be highly efficient – the US DOE’s future efficiency target is around 150 lumens per watt (lm/W) – although it is estimated that LEDs will always be more efficient. The advantages are that OLEDs offer more design flexibility than LEDs and contain no toxic metals. OLEDs are quite expensive today, but future manufacturing technologies will enable cheap, large-size panel production: e.g., ink-jet printing and roll-to-roll printing.
During the past few years we’ve witnessed fast progress in OLED technology. At Lighting+Building 2012, several companies exhibited impressive new OLED installations and designer luminaires. OLEDs were all over the show. Most experts agree that OLED technology will play a major role in future lighting markets, together with LEDs and CFL lamps. The real market breakthrough is expected around 2014-15.
The first OLED lighting fixture was introduced by OSRAM back in 2008. The desk lamp, designed by renowned lighting designer Ingo Maurer, used 10 OLED panels, and OSRAM only ever made 25 fixtures (each costing around €25,000!). Today, several companies are producing premium OLED lamps; but still, the cheapest OLED lamps cost around US$500.
In 2009, Philips became the first company to offer OLED panels, under the Lumiblade brand. Lumiblade panels are being offered mostly to designers and OEMs allowing them to experiment with the new technology. Philips also sells panels for premium commercial installations. For example, Aston Martin’s new showroom has 800 Lumiblade panels hanging from the ceiling.
Other companies to offer sample lighting panels include OSRAM, Lumiotec, LG Chem, Panasonic Idemitsu OLED Lighting, Verbatim, the Fraunhofer Institute, and Konica Minolta. And we expect more companies to throw their panels into the ring in the near future.
Most of these OLED panels are not very efficient (only 15 lm/W to about 50 lm/W), small in size, and are made on rigid glass substrates. The Fraunhofer is the first (and only) company to offer transparent panels, under the Tabola brand. Verbatim offers color-tunable panels, in which you can choose the light’s color on the fly. Some companies, such as LG Chem, focus on efficiency. The largest OLED panel on the market today is Lumiotec’s 15-by-15 centimeter panel.
Due to the premium price, OLED panels are still found only in very high-end fixtures and installations, such as art lighting and in showrooms. Low efficacy, low brightness, and low production capacity continue to prevent the technology from entering the general and commercial markets. Some analysts actually believe that OLEDs will never be able to compete with CFLs and LEDs and will remain a niche technology.
OLED lighting has enjoyed a lot of interest and investment in the past few years – driven by high energy costs and large government investments into clean and efficient technologies. The US Department of Energy is supporting several OLED lighting projects, while the EU is funding and encouraging projects across Europe in which commercial entities and universities collaborate. Companies from Japan, Korea, Taiwan, and China are also very active in OLED lighting. In fact, OLED display makers (for televisions, tablets, and cell phones) such as Samsung and LG have a distinct advantage, as a lot of the technologies and expertise are shared between OLED displays and lighting panels.
Dozens of companies have invested in OLED lighting: from materials makers like Universal Display and Novaled to panel (or “lamp”) producers such as Philips and OSRAM. Virtually all of the larger lighting companies have an active OLED program.
But challenges remain for OLED technology. Panels need to be larger, brighter, more efficient, and more durable for longer lifetimes. Advanced features such as color-tunability, flexibility, and transparency are still not really ready for production.
The major problem facing OLEDs today is price. The cheaper manufacturing processes just aren’t available yet, making production capacity very limited. Because the technology is still in its infancy, it isn’t likely that anyone will invest the billions of dollars needed to build a mass production facility. Perhaps by 2014-15 the technology will mature and companies will make large investments toward mass production.
Written by Ron Mertens, editor-in-chief of OLED-Info.com, the web’s leading OLED website. Mertens has been following OLEDs since 1998, and is author of The OLED Handbook, a comprehensive guide to OLED technology, industry, and markets. The handbook’s 2012 edition was released in April 2012.