Design of highly efficient RGB top-emitting organic light-emitting diodes using finite element method simulations.

In this paper, we present finite element method simulations of top-emitting organic light-emitting diodes for designing optimized red, green, and blue full-color device structures. The OLED structures in the simulation are used to evaluate the device parameters, such as the outcoupling efficiency, electroluminescence spectra, and angular emission characteristics on organic layers with varying thickness and different cathodes. The numerical study also extracts these parameters for nano-structured devices.

Light outcoupling enhancement from top-emitting organic light-emitting diodes made on a nano-sized stochastic texture surface.

An effective method for enhancing the light outcoupling efficiency from top-emitting organic light-emitting diodes (TEOLEDs) with a nano-sized stochastic texture surface (NSTS) is suggested. The broadly distributed pitch and the randomly sized of islands in the NSTS enable the photons that are otherwise trapped to be emitted over the broad emission wavelength range. The NSTS-embedded TEOLEDs have wide angular-dependent emission characteristics and an enhanced external quantum efficiency (EQE).