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Applied Optics

Applied Optics


  • Editor: James C. Wyant
  • Vol. 47, Iss. 7 — Mar. 1, 2008
  • pp: 957–966

Optimization of freeform lightpipes for light-emitting-diode projectors

Florian Fournier and Jannick Rolland  »View Author Affiliations

Applied Optics, Vol. 47, Issue 7, pp. 957-966 (2008)

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Standard nonimaging components used to collect and integrate light in light-emitting-diode-based projector light engines such as tapered rods and compound parabolic concentrators are compared to optimized freeform shapes in terms of transmission efficiency and spatial uniformity. We show that the simultaneous optimization of the output surface and the profile shape yields transmission efficiency within the étendue limit up to 90% and spatial uniformity higher than 95%, even for compact sizes. The optimization process involves a manual study of the trends for different shapes and the use of an optimization algorithm to further improve the performance of the freeform lightpipe.

© 2008 Optical Society of America

OCIS Codes
(120.2040) Instrumentation, measurement, and metrology : Displays
(230.3670) Optical devices : Light-emitting diodes
(220.2945) Optical design and fabrication : Illumination design
(220.4298) Optical design and fabrication : Nonimaging optics

ToC Category:
Optical Design and Fabrication

Original Manuscript: October 18, 2007
Revised Manuscript: December 10, 2007
Manuscript Accepted: December 14, 2007
Published: February 28, 2008

Florian Fournier and Jannick Rolland, "Optimization of freeform lightpipes for light-emitting-diode projectors," Appl. Opt. 47, 957-966 (2008)

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