Adjustable white-light emission from a photo-structured micro-OLED array

Color-tunable white organic light-emitting diodes (OLEDs) with alternating blue and yellow emitters have been fabricated. These emitters are arranged in thin alternating strips just a few tens of micrometers wide and are produced by photolithography. The micro-OLED array provides color tuning of the emitted light from blue to yellow, including warm and cold white light, without any change in brightness. Developed by researchers at Dresden University of Technology in Germany, the OLED array operates with a high luminous efficacy. Unlike previous two-color devices, based on separate sub-modules, this latest design does not suffer from dark regions between emitters; its entire surface area emits light. The OLED array can be tuned to emit light with a color rendering index of 68—one of the highest values achieved for a two-emitter system.