Great news today from the researchers from Singapores institute of materials research and engineering (imre) and the university of Michigan.
Both developed a blue organic light emitting diode with an efficiency that is double that of the maximum theoretical efficiency limit.This paves the way for longer-lasting, more efficient and vivid OLED displays for the consumer market.
Blue is always a problem because blue OLED materials does not have so long lifetimes like red, green.
The efficiency of fluorescent blue OLED devices can reach 9.4%, trumping the current theoretical limit for OLED external quantum efficiency by nearly two-fold. The researchers discovered that by changing the thickness of the light emitting layer and optimising the concentration of light emitting material in the same layer they could double the OLED efficiency from the current maximum 5% EQE.
This result could greatly enhance the attractiveness of OLED displays in the consumer market.
Current OLED displays are either phosphorescent or fluorescent materials displays. Though phosphorescent OLEDs have efficiencies that reach 11%, they are less stable, have shorter lifetimes and produce poor colour quality with their light blue colour emissions. Blue light has a wider band gap that requires higher energy for effective blue light emission, and inherently has lower efficiency and a shorter lifetime.
Source:a-star.edu
