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Energy Express

Energy Express

  • Editor: C. Martijn de Sterke
  • Vol. 19, Iss. S6 — Nov. 7, 2011
  • pp: A1272–A1280

Microporous phase-separated films of polymer blends for enhanced outcoupling of light from OLEDs

Rui Liu, Zhuo Ye, Joong-Mok Park, Min Cai, Ying Chen, Kai-Ming Ho, Ruth Shinar, and Joseph Shinar  »View Author Affiliations


Optics Express, Vol. 19, Issue S6, pp. A1272-A1280 (2011)
http://dx.doi.org/10.1364/OE.19.0A1272


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Abstract

Thin microporous films were formed by dropcasting a toluene solution containing various ratios of polystyrene:polyethylene glycol blends on a glass substrate, with OLEDs on the ITO that coated the opposite side of that substrate. We demonstrate for the first time that such easily-fabricated films with surface and bulk micropores in the index-matching polystyrene can serve as random microlens-like arrays to improve forward OLED light extraction by up to ~60%. A theoretical interpretation of the angular emission profile of the device, considering the geometrical change at the substrate/air interface and the scattering by the pores within the films, was established in excellent agreement with the experiments. The use of such blended thin films provides an economical method, independent of the OLED fabrication technique, for improving the outcoupling efficiency.

© 2011 OSA

OCIS Codes
(080.3630) Geometric optics : Lenses
(230.3990) Optical devices : Micro-optical devices

ToC Category:
Light-Emitting Diodes

History
Original Manuscript: August 15, 2011
Revised Manuscript: October 6, 2011
Manuscript Accepted: October 7, 2011
Published: November 7, 2011

Virtual Issues
Organic Light-Emitting Diodes (2011) Optics Express
November 11, 2011 Spotlight on Optics

Citation
Rui Liu, Zhuo Ye, Joong-Mok Park, Min Cai, Ying Chen, Kai-Ming Ho, Ruth Shinar, and Joseph Shinar, "Microporous phase-separated films of polymer blends for enhanced outcoupling of light from OLEDs," Opt. Express 19, A1272-A1280 (2011)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-19-S6-A1272


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