Project improves efficiency of OLED lighting panels

The 20-million euro (around $31 million) Organic LEDs for Lighting Applications (OLLA) project that has been partly funded by the European Union since 2004 has concluded, claiming it met and exceeded its goals and produced record-breaking OLED lighting panels. The collaborative research project was concluded in Eindhoven, the Netherlands.

The consortium, led by Philips Lighting, along with Covion Organic Semiconductor GmbH, Novaled GmbH, Osram Opto Semiconductors GmbH, Royal Philips Electronics, Philips Lighting GmbH and Siemens AG, presented technology for a white OLED light source, with an efficacy of 50.7cdsr/W at an initial brightness of 1,000cd/m² based on the Novaled PIN OLED technology.

What OLLA project offers
In the collaborative research projects commercial participants can get up to half of their costs paid by the European Commission and academic institutions can receive up to 75 percent of their costs. OLLA did not indicate how much money has been granted. Half of the budget would be 10 million euros (around $15.5 million).

The OLED technology is generating novel solid-state light sources, which are flat, thin and lightweight. Because of the freedom of design, OLED lighting technology offers many possibilities for new lighting applications achieving substantial energy savings. About 24 partners worked within OLLA with the goal of reaching an efficacy of 50cdsr/W combined with a lifetime of over 10,000h at 1,000cd/² initial brightness in a tile measuring 15cm x 15cm. The target was reached in terms of efficacy, color rendering and brightness. The lifetime of the Novaled device has exceeded the promised value by one order of magnitude.

The future of OLED
"The high efficiency combined with the extrapolated lifetime values prove that OLED is a serious technology for lighting applications, allowing innovative design capabilities and energy savings for future lighting products. It is a very important step toward the introduction of OLED technology in the lighting market," said Peter Visser, OLLA project manager, Philips Lighting.

"The Novaled PIN technology has the potential to further improve the power efficiency. It's in line with the technology road map that in the near future some 100cdsr/W OLEDs will be achievable," said Martin Vehse, Novaled.

"Collecting all light of the device in a laboratory set-up with a macroextractor, we measure even more than 80cdsr/W," said Volker van Elsbergen, Philips Research. "This shows that one of the keys to higher efficiencies will be better light outcoupling technologies," he added.

The OLLA project also delivered the first large-sized ITO-free OLEDs, the first large-area printed OLEDs and several demonstrators.

- Peter Clarke
EE Times Europe