Enhancement of spectral stability and outcoupling efficiency in organic light-emitting diodes with breath figure patterned microlens array films

Abstract

We report outcoupling efficiency enhanced organic light-emitting diodes (OLEDs) using microlens array films prepared by a simple solution-processed imprinting technique with breath figure patterns. The films with breath figure micro-patterns (BFMP) effectively extract confined light in the glass substrate, which leads to the greatly improved outcoupling performance of OLEDs. We observe the enhancement of external quantum efficiency of the OLEDs employing the BFMP outcoupling film is about 1.51, corresponding to the enhancement of the power efficiency by a factor of 1.65. Moreover, the device with the outcoupling film shows the limited angle-dependency of emission spectrum over viewing angles. The BFMP films prepared with a low-cost, simple, and solution-processable fabrication process can pave the way to achieving high-performance OLEDs.