Towards High Performance Large Area Two Color Hybrid White Organic Light Emitting Diodes for Lighting Applications
White organic light-emitting diodes (WOLEDs) are ideal candidates for next generation solid state lighting. In order to overcome that operational stability limitation of all phosphorescent material based OLEDs, hybrid WOLED with a combination of blue emitting florescent and phosphorescence based other color emitting systems are used. In this study, hybrid WOLED by fabricating WOLED devices with varying dopant concentration and layer thickness were fabricated and tested for their performances and stability. The power efficiencies of the devices were found to vary from 3.43 to 16.5 lm/W and devices showed a wide color range from cool white (CIE—0.34, 0.42) to warm white (CIE—0.47, 0.48) and moving towards yellow color. The devices fabricated over an area of 16 mm2 showed good performance and color stability at constant current driving and showed lifetime of T90 of 60 min at brightness of 3000 cd/m2.
We would like to acknowledge Ministry of Electronics and Information Technology (MEITY), Govt. of. India for the guidance and financial support for the project.