High Efficiency White Mesh Phosphorescent OLEDs

78708S In 2001, lighting is estimated to consume 8.2 quads (approximately 762 TWh), or about 22% of the total electricity generated in the U.S. New, high efficiency solid state light sources, such as light emitting diodes (LEDS) and organic LEDs (OLEDS), are needed to reduce the ever increasing demand for energy. An OLED is potentially a cost effective diffuse light source that may compete most directly with conventional incandescent light sources; however, improvements in the overall efficiency of these devices are still required before they become commercially viable and attain expected cost and performance goals (of $3 per 1000 lumens and 90 lumens per watt, respectively). This project first will utilize a novel low cost manufacturing technique, Organic Vapor Phase Deposition (OVPD), to study and optimize the doping profile in the emissive layer of a high efficiency phosphorescent OLED (PHOLED), in order to increase efficiency. Secondly, new OLED designs will be identified that will simplify OLED production using conventional deposition techniques, such as Vacuum Thermal Evaporation. Phase I will utilize OVPD to explore various doping profiles of the emissive region that may increase the external quantum efficiency of PHOLEDs. Then, the color and efficiency of a white mesh PHOLED will be optimized by experimenting with the blue, red, and green mesh layer stacking order, the 'thickness' of the mesh layers, and the ratio of the number of blue to red to green mesh layers. Finally, a mesh PHOLED (with >30 lmW-1 at 800 nits luminance, with a CIE of (0.33, 0.33) and CRI > 75) will be characterized and demonstrated. Commercial Applications and Other Benefits as described by the awardee: The new technology should make OLEDs even more cost-effective in general lighting applications. In addition, OLED technology has become an emerging technology for flat panel displays (FPDs), with recent product introductions in an automotive audio product and portable cell phones. Many of the desired features for FPDs are making OLED technology of great interest to the solid-state lighting community because OLEDs are: (1) bright white lambertian emitters with excellent power efficiency at low voltages; (2) thin-film devices that provide excellent form factor especially when built on flexible plastic substrates; and (3) less materials intensive, have fewer processing steps, and consequently are projected to have lower manufacturing costs.