Novel source to beat blue âbottleneckâ in OLED displays 06 Jan 2021 Researchers in Japan achieve breakthrough with new combination of emitter molecules. True blue: Highly efficient, pure-blue OLEDs under test.Employing a new combination of emitter molecules, researchers in Japan have demonstrated the promise of a novel approach to overcoming a challenge that has limited the performance of OLED displays: a blue light source to match the relatively better performance of the red and green ones. By splitting energy conversion and emission processes between two molecules, the Kyushu University researchers have achieved devices that produce pure-blue emission at high efficiency, maintain brightness for relatively long times, and lack any expensive metal atoms â a combination of properties that has so far been difficult to obtain simultaneously.