High efficiency, color stability, and stable efficiency roll off in three color hybrid white organic light emitting diodes

High efficiency, good color stability, and stable efficiency roll off were achieved in three color white organic light emitting diodes by developing a device architecture with red and green phosphorescent materials codoped in a mixed host emitting structure. A fluorescent blue material was used in a blue emitting layer and a mixed interlayer structure was applied. A high quantum efficiency of 9.7% was obtained and color coordinate of (0.40, 0.40) was kept constant up to luminance of 10 000 cd/m(2). In addition, efficiency decrease at 10 000 cd/m(2) was only 2% of the maximum quantum efficiency. (C) 2008 American Institute of Physics.