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

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

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.

Inventors:: Leung, Wai Y.; Park, Joong-Mok; Gan, Zhengqing; Constant, Kristen P.; Shinar, Joseph; Shinar, Ruth; ho, Kai-Ming

Issue Date:: 2014-06-03

OSTI Identifier:: 1133638

Assignee:: Iowa State University Research Foundation, Inc. (Ames, IA) CHO

Patent Number(s):: 8,742,406

Application Number:: 13/397,749

Contract Number:: AC02-07CH11358

Research Org:: Ames Laboratory (AMES), Ames, IA (United States)

Sponsoring Org:: USDOE

Country of Publication:: United States

Language:: English

Subject:: 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 42 ENGINEERING

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