Universal Display and Samsung Present Advances in Highly Efficient, Long Lifetime Green PH-OLEDs
Universal Display and Samsung Mobile Displays present advances in green Phosphorescent OLEDs at SID. This new material will be used in both hand-held devices and OLED TVs, extending lifetime and efficiency. UDC's red materials are already used in Samsung's AMOLED displays, and it's likely that we'll see Samsung use their green materials as well.
The companies showed a highly-efficient, green UniversalPHOLED material that has been used in a top-emission PHOLED device architecture. Using this approach, they achieved two milestones. A green PHOLED with NTSC color at CIE(0.20, 0.73), high luminous efficiency of 110 candelas per Ampere (cd/A), and a low voltage of 3.6 V at 3,000 candelas per square meter (cd/m2) was achieved.
A second device structure using this green PHOLED material system also achieved an ultra-high luminous efficiency of 160 cd/A along with CIE(0.28, 0.69) and low voltage of 3.8 V at 3,000 cd/m2. These compare to a standard bottom-emission device with CIE(0.33, 0.62) and 52 cd/A using this same green PHOLED material system. Replacing the green fluorescent OLED material typically used today in an AMOLED with this new green PHOLED can result in a significant 37% power savings.
The operational lifetime for this green PHOLED material system is also very good. A bottom-emission device using this material system offers > 300,000 hours to 50% (extrapolated) and 15,000 hours to 90% of the initial luminance of 1000 cd/m2 (defined as LT90). With these top-emission devices, the LT90 lifetime is 28,000 hours and 6,400 hours, respectively, for the 110 cd/A and 160 cd/A devices.