Omnidirectional emission from top-emitting organic light-emitting devices with microstructured cavity

Area of Science:

• Optoelectronics
• Materials Science

Background:

• Top-emitting organic light-emitting devices (OLEDs) often suffer from viewing-angle dependence.
• This dependence affects the peak emission wavelength and intensity, impacting display quality.

Purpose of the Study:

• To optimize viewing-angle characteristics of top-emitting OLEDs.
• To suppress the angular dependence of emission properties.
• To achieve omnidirectional emission.

Main Methods:

• Integration of a periodic microstructure into the OLED cavity.
• Utilizing holographic lithography to create the microstructure.
• Employing spin coating of a polymer film to fill grooves and create a gradually changed cavity length.

Main Results:

• Successfully demonstrated optimized viewing-angle characteristics.
• Suppressed the viewing-angle dependence of peak emission wavelength and intensity.
• Achieved desired omnidirectional emission through the microstructured cavity design.

Conclusions:

• The proposed microstructured cavity effectively resolves angular-dependence issues in OLEDs.
• The integration of periodic microstructures offers a simple and effective solution.
• The method enables high-quality, angle-independent light emission.