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Energy Express

  • Editor: Bernard Kippelen
  • Vol. 20, Iss. S1 — Jan. 2, 2012
  • pp: A75–A84

Collimating lamp with well color mixing of red/green/blue LEDs

Ching-Cherng Sun, Ivan Moreno, Yi-Chien Lo, Bo-Chun Chiu, and Wei-Ting Chien  »View Author Affiliations

Optics Express, Vol. 20, Issue S1, pp. A75-A84 (2012)

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A novel light luminaire is proposed and experimentally analyzed, which efficiently mixes and projects the tunable light from red, green and blue (RGB) light-emitting diodes (LEDs). Simultaneous light collimation and color mixing is a challenging task because most collimators separate colors, and most color mixers spread the light beam. Our method is simple and compact; it only uses a short light pipe, a thin diffuser, and a total internal reflection lens. We performed an experimental study to find a balance between optical efficiency and color uniformity by changing light recycling and color mixing.

© 2011 OSA

OCIS Codes
(230.3670) Optical devices : Light-emitting diodes
(330.1690) Vision, color, and visual optics : Color
(350.4600) Other areas of optics : Optical engineering
(080.4295) Geometric optics : Nonimaging optical systems

ToC Category:
Light-Emitting Diodes

Original Manuscript: May 31, 2011
Revised Manuscript: November 8, 2011
Manuscript Accepted: December 5, 2011
Published: December 16, 2011

Ching-Cherng Sun, Ivan Moreno, Yi-Chien Lo, Bo-Chun Chiu, and Wei-Ting Chien, "Collimating lamp with well color mixing of red/green/blue LEDs," Opt. Express 20, A75-A84 (2012)

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  19. We chose a 29 cm diameter because more than 95% of the luminous energy is enclosed within this circle. At this radial position the view angle of the circle is 20 degrees. From Fig. 5b it can be seen that the intensity is quite low at this emission angle.

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