Analytical Measurements for Quantum Efficiency of Organic Light Emitting Diodes

Abstract

Electroluminescence (EL) in organic displays and lighting devices has shown steady progress. The electronic devices based on
organic semiconductors are expected to serve the society in near future where solid state lighting is an important example. In the present paper we have attempted, from the first principles, to provide an analytical approach for calculation of external quantum efficiency (EQE) of organic light emitting diodes (OLEDs). This approach requires only the EL  spectrum and illumination versus current characteristics of the devices to calculate the EQE. In these calculations the light emission has been considered to be perfectly diffusive from the emission surface. The efficiencies calculated in this way have been compared with the actual values of the EQEs for the different OLED structures available in the literature. The calculated values have shown good agreement with the  measured values.