Efficient phosphorescent white OLEDs with high color rendering capability

By utilizing a newly developed deep-blue iridium complex along with efficient green and orange-red phosphors, we have successfully demonstrated efficient three-component phosphorescent white-emitting organic light-emitting devices (WOLEDs) with excellent performances. Such WOLEDs were based on the deep-blue phosphorescent OLEDs architecture with double emitting layers and double confining layers; portions of the deep-blue phosphors were selectively replaced with green and orange-red phosphors, thereby forming a structure with the green/orange-red emitting layers sandwiched between the two deep-blue emitting layers. Such three-component phosphorescent WOLEDs yielded a high color rendering index (CRI) of up to 94 and Commission Internationale de l'Eclairage (CIE) coordinates close to the ideal equal-energy white (0.33, 0.33). Furthermore, they exhibited rather stable colors and high CRI over a wide brightness range of 10(2)-10(4) cd/m(2) and yielded electroluminescence efficiencies of up to 10.3%, 24.0 cd/A and 16.4 lm/W for the forward directions. (C) 2009 Elsevier B.V. All rights reserved.