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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 16, Iss. 1 — Jan. 7, 2008
  • pp: 13–18

Spectral conversion with fluorescent microspheres for light emitting diodes

K. N. Hui, P. T. Lai, and H. W. Choi  »View Author Affiliations


Optics Express, Vol. 16, Issue 1, pp. 13-18 (2008)
http://dx.doi.org/10.1364/OE.16.000013


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Abstract

An innovative spectral conversion scheme for light emitting diodes using fluorescent microspheres has been demonstrated. An optimally mixed proportion of green and red fluorescent microspheres were coated onto a high-extraction-efficiency GaN micro-LED with emission centred at 470 nm. The microspheres self-assemble into ordered hexagonally arrays, forming regular and uniform coating layers. Devices with cool and warm white emission were achieved. The bluish-white LED has a luminous efficacy of 27.3 lm/W (at 20 mA) with CIE coordinates of (0.26, 0.28) and 8500K CCT, while the yellowish-white LED has a luminous efficacy of 26.67 lm/W (at 20 mA) with CIE coordinates of (0.36, 0.43) and 13000K CCT.

© 2008 Optical Society of America

OCIS Codes
(160.2540) Materials : Fluorescent and luminescent materials
(230.3670) Optical devices : Light-emitting diodes

ToC Category:
Optical Devices

History
Original Manuscript: October 15, 2007
Revised Manuscript: December 4, 2007
Manuscript Accepted: December 16, 2007
Published: December 21, 2007

Citation
K. N. Hui, P. T. Lai, and H. W. Choi, "Spectral conversion with fluorescent microspheres for light emitting diodes," Opt. Express 16, 13-18 (2008)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-16-1-13


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