Organic LED

Silicon Valley-based SRI International and the Japanese firm SDK have produced a highly efficient light source that could one day replace incandescent and fluorescent light bulbs.

Silicon Valley-based SRI International and the Japanese firm SDK have produced an efficient organic light-emitting diode (OLED) light source that could one day replace incandescent and fluorescent light bulbs.

A combination of SDK's light-emitting polymer materials and SRI's cavity organic light-emitting diode (COLED) technology has enabled researchers to achieve an output of 30 lumen per watt for blue light  higher than any other reported polymer OLED device.

Philip von Guggenberg, director of business development at SRI International, said: 'With our new design, SRI has significantly increased the efficiency of OLED devices.'

For green light, the team has achieved more than 80 lumen per watt  about three times higher than a traditional OLED.

To produce white light that is acceptable for illumination, a mix of red, green, and blue light is required, with blue being the most technically challenging to produce. The results from SRI and SDK’s research indicate that it might well be feasible to produce a white light source of sufficient quality at a low cost.

Kyohei Takahashi, president of SDK, added: 'With SRI’s help, we expect to make this technology available to the lighting industry as early as 2010.'