Comparative study of single and multiemissive layers in inverted white organic light-emitting devices

The authors have fabricated and compared highly efficient inverted white organic light-emitting devices (WOLEDs) with a single emission layer (SEL) and with a multiemission layer (MEL). The efficiency levels of the WOLEDs with a SEL and a MEL achieved 13.0cd∕A, 10.6lm∕W and 11.3cd∕A, 7.3lm∕W, respectively. The projected half lifetime of a SEL device under an initial luminance of 400cd∕m2 is expected to be over 34000h, which is five times better than that of a MEL device of 6350h. The Commission International de l’Eclairage coordinates of a SEL device are not affected by aging.