Highly efficient white organic light-emitting diode

Abstract
We present a highly efficient white electroluminescence device by the combination of a solution processed blue organic phosphorescence light-emitting diode with appropriate down-conversion phosphor system. The use of this down-conversion system produced an extraordinary enhancement on device performance, resulting in a white electroluminescence device with luminance efficacy of 25 lm ∕ W at luminance efficiency reaching 39 cd ∕ A . The extraordinary enhancement on device performance is attributed to isotropic radiation pattern of the excited phosphor particles, leading to high light extraction properties.