Identification of White Light Emission with Two Complementary Colors in Organic Light-Emitting Devices

Abstract

Simple method of determining emission light color in organic light-emitting diodes (OLEDs) with two emissive materials from their electroluminescent (EL) spectra has been presented. The Commission Internationale de l'Eclairage (CIE) coordinates and two EL intensity rates of OLEDs can be simulated with this method. White light OLEDs were fabricated with a blue light emission from 4,4'-bis[N-1-napthyl-N-phenyl-amino]biphenyl (NPB) and a yellow light emission from bis[2-(4-tert-butylphenyl)benzothiazolato-N,C2’]iridium (acetylacetonate) [(t-bt)2Ir(acac)], and the device shows the CIE coordinates of (0.34, 0.32) at 10 V bias, which located in white light region.