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Optics Letters

Optics Letters


  • Editor: Alan E. Willner
  • Vol. 35, Iss. 11 — Jun. 1, 2010
  • pp: 1860–1862

Angular color uniformity enhancement of white light-emitting diodes integrated with freeform lenses

Kai Wang, Dan Wu, Fei Chen, Zongyuan Liu, Xiaobing Luo, and Sheng Liu  »View Author Affiliations

Optics Letters, Vol. 35, Issue 11, pp. 1860-1862 (2010)

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We demonstrate a freeform lens to enhance the angular color uniformity (ACU) of white light-emitting diodes (LEDs) whose phosphor layers were coated by freely dispersed coating processes. Monte Carlo ray tracing simulation results indicated that the ACU of the modified LED integrated with the freeform lens significantly increased from 0.334 to 0.957, compared with the traditional LED. Enhancement of ACU reached as high as 186.5%. Moreover, the ACU of the modified LED was not only at a high level, but also stable when the shape of the phosphor layer changed. The freeform lens provided an effective way to achieve white LEDs with high ACU at low cost.

© 2010 Optical Society of America

OCIS Codes
(220.3630) Optical design and fabrication : Lenses
(230.3670) Optical devices : Light-emitting diodes
(330.1690) Vision, color, and visual optics : Color
(220.4298) Optical design and fabrication : Nonimaging optics

ToC Category:
Optical Devices

Original Manuscript: February 26, 2010
Revised Manuscript: April 25, 2010
Manuscript Accepted: May 2, 2010
Published: May 25, 2010

Kai Wang, Dan Wu, Fei Chen, Zongyuan Liu, Xiaobing Luo, and Sheng Liu, "Angular color uniformity enhancement of white light-emitting diodes integrated with freeform lenses," Opt. Lett. 35, 1860-1862 (2010)

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