Hybrid OLED having phosphorescent and fluorescent emitters

摘要

The present invention provides organic light emitting devices having a combined emission from at least two emissive materials, a fluorescent blue emissive material and a phosphorescent emissive material. The device may further comprise additional fluorescent or phosphorescent emissive materials. In preferred embodiments, the invention provides OLEDs having three different emissive materials—a red emissive material, a green emissive material and a blue emissive material. The invention provides a device architecture which is optimized for efficiency and lifetime by using a combination of fluorescent and phosphorescent emitters. Further, in preferred embodiments the device architecture provides a high color-stability of the light emission over a wide range of currents or luminances.

主权项

1. An organic light emitting device comprising:
a cathode; a first emissive layer comprising a fluorescent blue emitting material as a dopant in a host material; a spacer layer; a second emissive layer comprising a phosphorescent emitting material as a dopant in a host material; and an anode;wherein, the spacer layer is between the first emissive layer and the second emissive layer, the spacer layer inhibits quenching of the triplet excitons in the second emissive layer;an interface between the spacer layer and the first emissive layer forms a heterojunction; andthe spacer layer comprises a material that has a triplet energy that is higher than the triplet energy of the phosphorescent emitting material; andwherein a combined emission of the emitting materials gives a white emission from the device.