Soft lithography microlens fabrication and array for enhanced light extraction from organic light emitting diodes (OLEDs)

US8742406B1 · kind B1 · utility

Assignee

• IOWA STATE UNIVERSITY RESEARCH FOUNDATION, INC. · US

Inventors

• Wai Y. Leung · Chicago, US
• Joong-Mok Park · Ames, US
• Zhengqing Gan · Clayton, US
• Kristen P. Constant · Ames, US
• Joseph Shinar · Ames, US
• Ruth Shinar · Ames, US
• Kai-Ming Ho · Ames, US

Key dates

• Filing date: Feb 16, 2012
• Grant date: Jun 3, 2014
• Expiry date: May 19, 2032

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10K59/879

Abstract

Provided are microlens arrays for use on the substrate of OLEDs to extract more light that is trapped in waveguided modes inside the devices and methods of manufacturing same. Light extraction with microlens arrays is not limited to the light emitting area, but is also efficient in extracting light from the whole microlens patterned area where waveguiding occurs. Large microlens array, compared to the size of the light emitting area, extract more light and result in over 100% enhancement. Such a microlens array is not limited to (O)LEDs of specific emission, configuration, pixel size, or pixel shape. It is suitable for all colors, including white, for microcavity OLEDs, and OLEDs fabricated directly on the (modified) microlens array.