Novaled, Germany achieved significant improvements for white OLEDs for lighting applications. An efficiency of 35lm/W and a lifetime of 100,000h were reached at a brightness of 1000 cd/m2.
Based on its proprietary Novaled PIN OLED® technology and materials, Novaled achieved significant improvements for white OLEDs for lighting applications. An OLED device with an efficiency of 35 lm/W at a brightness of 1,000 cd/m2 and a lifetime of above 100,000 h has been realized. The device exhibits CIE colour coordinates of x,y = 0,43/0,44 with a colour rendering index CRI of 90.
The OLED features a stacked setup with blue fluorescent and red/green phosphorescent emitter materials (hybrid approach). For the stacking layer and transport layer Novaled proprietary materials have been used. The OLED device is equipped with a standard outcoupling enhancement film. The measurement was carried out in an integrating sphere taking into account only the full forward emission with substrate edges and backside covered, thus corresponding to a real case application. At a brightness level of 4,000 cd/m2 the efficiency is 31 lm/W, with no significant changes in colour and CRI value.
"With this achievement Novaled proves once more the advantages of its technology and associated materials for an OLED device combining high performance and long lifetime", says Jan Birnstock, Novaled VP Technology Transfer. "We are working on enhanced outcoupling solutions and large area devices. When associated with a proper phosphorescent blue, we are confident of reaching 100 lm per W combined with a long lifetime in the near future."
OLEDs are made of thin organic material layers which are only a few nanometers thick. They emit light in a diffuse way as an area light source. In the fast growing market for printed and potentially printed electronics, OLEDs are key part of a revolution: the dream of paper thin, highly efficient lighting with brilliant colours and a great flexibility in design is becoming reality. OLEDs represent the future of a vast array of completely new lighting applications and, at the same time, offer the potential to become even more efficient than energy-saving bulbs.
Novaled AG is engaged in the research, development and commercialization of organic light-emitting diode (OLED) technologies and proprietary materials. The Company is a spin-off of the Dresden University and the Fraunhofer-Gesellschaft.
For more attend Printed Electronics Europe 2008