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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 20, Iss. 5 — Feb. 27, 2012
  • pp: 4819–4829

Polarized backlight with constrained angular divergence for enhancement of light extraction efficiency from wire grid polarizer

Po-Hung Yao, Chi-Jui Chung, Chien-Li Wu, and Cheng-Huan Chen  »View Author Affiliations


Optics Express, Vol. 20, Issue 5, pp. 4819-4829 (2012)
http://dx.doi.org/10.1364/OE.20.004819


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Abstract

Efficiency of liquid crystal displays highly depends on the amount of polarized light emerging from the backlight module. In this paper, a backlight architecture using a nanoimprint wire grid polarizer for polarization recycling is proposed and studied, in which the extraction efficiency of polarized light is the major concern. The backlight module is composed of the stack of a wire grid polarizer, a lenticular array and a light guide plate. The light guide plate features interleaving v-groove and trapezoidal ridge coated with aluminum on the top surface, and scattering dot array on the bottom. The angular divergence of emerging light from the light guide plate can be well constrained so as to exploit the angular range with the best transmission of polarized light for the wire grid polarizer. The prototype of a 2.5-inch module has demonstrated an angular divergence of 48°. The overall extraction efficiency of polarized light enhanced by 21% and uniformity of 76% have been achieved.

© 2012 OSA

OCIS Codes
(120.2040) Instrumentation, measurement, and metrology : Displays
(220.4000) Optical design and fabrication : Microstructure fabrication
(110.2945) Imaging systems : Illumination design

ToC Category:
Instrumentation, Measurement, and Metrology

History
Original Manuscript: November 11, 2011
Revised Manuscript: January 20, 2012
Manuscript Accepted: January 21, 2012
Published: February 13, 2012

Citation
Po-Hung Yao, Chi-Jui Chung, Chien-Li Wu, and Cheng-Huan Chen, "Polarized backlight with constrained angular divergence for enhancement of light extraction efficiency from wire grid polarizer," Opt. Express 20, 4819-4829 (2012)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-20-5-4819


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