Thanks to intensive research in the past three decades, organic light-emitting diodes (OLEDs) have been steadily conquering the electronics market — from OLED mobile phone displays to roll-out television screens, the list of applications is long. Current OLED research focuses in particular on improving the performance of white OLEDs for lighting elements such as ceiling or car interior lighting. These components are subject to much stricter requirements in terms of stability, angular emission and power efficiency.