BASF and Osram say they have developed a white OLED with high efficacy of 60 lm/W.
Although efficiency at this level or above has been achieved previously, the colour values of OLEDs have not been within the acceptable band for colour coordinates around the Planck curve.
By developing a white OLED with a high light yield, the two companies claim to have completed a major step on the way towards commercial OLED lighting. BASF and Osram are conducting research together within the framework of the “OLEDs for Applications on the Lighting Market” (OPAL) project, which is sponsored as part of the OLED Initiative of the German Federal Ministry for Education and Research.
The new OLEDs contain phosphorescent metal complexes as emitter materials and customized complementary materials, which ensure optimum constancy of the color temperatures. That means that, owing to the use of new materials, the diodes are very color-stable even when there are variations in luminous intensity. The challenge now is to optimize the life of these OLED tiles, especially by stabilizing the blue emitters.
BASF are dealing with the material side of the OLEDs and, within the framework of the OPAL project, are developing the optimum component structures in partnership with Philips and Osram.