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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 17, Iss. 9 — Apr. 27, 2009
  • pp: 7562–7570

Exceptionally efficient organic light emitting devices using high refractive index substrates

Saso Mladenovski, Kristiaan Neyts, Domagoj Pavicic, Ansgar Werner, and Carsten Rothe  »View Author Affiliations


Optics Express, Vol. 17, Issue 9, pp. 7562-7570 (2009)
http://dx.doi.org/10.1364/OE.17.007562


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Abstract

Organic light emitting devices (OLEDs) are now used in commercial cell phones and flat screen displays, but may become even more successful in lighting applications, in which large area, high efficiency, long lifetime and low cost are essential. Due to the relatively high refractive index of the organic layers, conventional planar bottom emitting OLEDs have a low outcoupling efficiency. Various approaches for enhancing the optical outcoupling efficiency of bottom emitting OLEDs have been introduced in the literature. In this paper we demonstrate a green bottom emitting OLED with a record external quantum efficiency (42%) and luminous efficacy (183 lm/W). This OLED is based on a high index substrate and a thick electron transport layer (ETL) which uses electrical doping. The efficient light outcoupling is modeled by optical simulations.

© 2009 OSA

OCIS Codes
(160.4890) Materials : Organic materials
(230.3670) Optical devices : Light-emitting diodes
(310.6860) Thin films : Thin films, optical properties
(310.6845) Thin films : Thin film devices and applications

ToC Category:
Optical Devices

History
Original Manuscript: February 9, 2009
Revised Manuscript: April 15, 2009
Manuscript Accepted: April 19, 2009
Published: April 23, 2009

Citation
Saso Mladenovski, Kristiaan Neyts, Domagoj Pavicic, Ansgar Werner, and Carsten Rothe, "Exceptionally efficient organic light emitting devices using high refractive index substrates," Opt. Express 17, 7562-7570 (2009)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-17-9-7562


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