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Updated: Jul 5, 2026
07:44
Production and Characterization of Vacuum Deposited Organic Light Emitting Diodes
Published on: November 16, 2018
High-contrast organic light emitting diodes with a partially absorbing anode
Christophe Py1, Daniel Poitras, Chien-Cheng Kuo
1Institute for Microstructural Sciences, National Research Council of Canada, 1200 Montreal Road, Ottawa, Ontario K1A 0R6, Canada. Christophe.py@nrc.ca
Optics Letters
|May 17, 2008
Summary
To improve outdoor visibility of organic light-emitting-diode (OLED) displays, a novel anode design minimizes light reflection. This approach enhances light absorption and outcoupling efficiency for brighter screens in high ambient light.
Area of Science:
- Materials Science
- Optoelectronics
- Display Technology
Background:
- Organic light-emitting-diode (OLED) displays require optical design for legibility in bright conditions.
- Minimizing display reflectance is crucial without compromising efficiency.
Purpose of the Study:
- To develop an optical design for OLED displays that reduces reflectance in high ambient light.
- To enhance light outcoupling efficiency using a novel anode structure.
Main Methods:
- Utilized an anode composed of a partially absorbing metal layer.
- Incorporated a multilayer distributed Bragg reflector within the anode structure.
- Leveraged a weak microcavity effect in the diode.
Main Results:
- The novel anode design effectively absorbs incoming light, reducing surface reflectance.
- The microcavity effect was exploited to improve light outcoupling from the OLED.
- Achieved reduced reflectance without significant negative impact on overall display efficiency.
Conclusions:
- A partially absorbing metal layer combined with a distributed Bragg reflector offers a viable solution for low-reflectance OLEDs.
- This anode design enhances display performance in high ambient light conditions by managing light interaction within the device.
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