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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 20, Iss. 13 — Jun. 18, 2012
  • pp: 13727–13737

Design of a novel freeform lens for LED uniform illumination and conformal phosphor coating

Run Hu, Xiaobing Luo, Huai Zheng, Zong Qin, Zhiqiang Gan, Bulong Wu, and Sheng Liu  »View Author Affiliations

Optics Express, Vol. 20, Issue 13, pp. 13727-13737 (2012)

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A conformal phosphor coating can realize a phosphor layer with uniform thickness, which could enhance the angular color uniformity (ACU) of light-emitting diode (LED) packaging. In this study, a novel freeform lens was designed for simultaneous realization of LED uniform illumination and conformal phosphor coating. The detailed algorithm of the design method, which involves an extended light source and double refractions, was presented. The packaging configuration of the LED modules and the modeling of the light-conversion process were also presented. Monte Carlo ray-tracing simulations were conducted to validate the design method by comparisons with a conventional freeform lens. It is demonstrated that for the LED module with the present freeform lens, the illumination uniformity and ACU was 0.89 and 0.9283, respectively. The present freeform lens can realize equivalent illumination uniformity, but the angular color uniformity can be enhanced by 282.3% when compared with the conventional freeform lens.

© 2012 OSA

OCIS Codes
(220.3630) Optical design and fabrication : Lenses
(230.3670) Optical devices : Light-emitting diodes
(350.4600) Other areas of optics : Optical engineering
(220.2945) Optical design and fabrication : Illumination design

ToC Category:
Optical Design and Fabrication

Original Manuscript: April 16, 2012
Revised Manuscript: May 16, 2012
Manuscript Accepted: May 21, 2012
Published: June 4, 2012

Run Hu, Xiaobing Luo, Huai Zheng, Zong Qin, Zhiqiang Gan, Bulong Wu, and Sheng Liu, "Design of a novel freeform lens for LED uniform illumination and conformal phosphor coating," Opt. Express 20, 13727-13737 (2012)

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