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Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 51, Iss. 16 — Jun. 1, 2012
  • pp: 3162–3170

Design of an elliptic spot illumination system in LED-based color filter–liquid-crystal-on-silicon pico projectors for mobile embedded projection

Enguo Chen and Feihong Yu  »View Author Affiliations

Applied Optics, Vol. 51, Issue 16, pp. 3162-3170 (2012)

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We present an elliptic spot illumination system for a color filter–liquid-crystal-on-silicon (CF-LCoS) pico projector employing a specifically designed free-form lens and a cylindrical lens to improve on previous designs in terms of optical efficiency while yielding an ultracompact and low-cost optical architecture. The detailed design description of the optical system is thoroughly investigated. Simulation results coincide well with the theoretical calculation. The single 1mm×1mm LED chip-powered optical engine, which employs a CF-LCoS panel with a diagonal of 0.28 in and an aspect ratio of 43, has an estimated output efficiency over 9.8% (11.8 lm@1 W) and an ANSI 9-point uniformity over 88.5%, with the ultrasmall volume 24mm×19mm×7mm. Compared to the circular spot-illuminated projection system, a total increment of about 23% of system efficiency is available with this improved optical engine. It is believed that there would be a huge market potential to commercialize our design.

© 2012 Optical Society of America

OCIS Codes
(220.4830) Optical design and fabrication : Systems design
(220.2945) Optical design and fabrication : Illumination design

ToC Category:
Optical Design and Fabrication

Original Manuscript: January 25, 2012
Revised Manuscript: February 24, 2012
Manuscript Accepted: February 27, 2012
Published: May 23, 2012

Enguo Chen and Feihong Yu, "Design of an elliptic spot illumination system in LED-based color filter–liquid-crystal-on-silicon pico projectors for mobile embedded projection," Appl. Opt. 51, 3162-3170 (2012)

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