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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 22, Iss. 4 — Feb. 24, 2014
  • pp: 4516–4522

Improvement of emission uniformity by using micro-cone patterned PDMS film

Che-Yu Liu, Kuo-Ju Chen, Da-Wei Lin, Chia-Yu Lee, Chien-Chung Lin, Shih-Hsuan Chien, Min-Hsiung Shih, Gou-Chung Chi, Chun-Yen Chang, and Hao-Chung Kuo  »View Author Affiliations

Optics Express, Vol. 22, Issue 4, pp. 4516-4522 (2014)

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Micro-patterned PDMS film was fabricated and combined with LED chip on board (COB) package to improve the emission uniformity of LED chip. The micro scale patterned sapphire substrate (PSS) was used as a mold to fabricate micro-cone patterned PDMS (MC-PDMS) film. A strong scattering effect from this MC-PDMS film can be verified by the high haze ratio and the Bi-directional Transmission effect. The angle dependent color temperature measurement system was used to measure the ΔCCT of COB with and without MC-PDMS. The measurement results indicate that the ΔCCT was reduced from 1025K to 428K. This improvement can effectively eliminate the yellow ring effect of LED chip. This technology can be thus considered as a cost-effective way for the next generation of light source packages.

© 2014 Optical Society of America

OCIS Codes
(230.2090) Optical devices : Electro-optical devices
(230.3670) Optical devices : Light-emitting diodes
(250.0250) Optoelectronics : Optoelectronics
(290.1483) Scattering : BSDF, BRDF, and BTDF

ToC Category:
Diffraction and Gratings

Original Manuscript: October 22, 2013
Revised Manuscript: January 28, 2014
Manuscript Accepted: February 4, 2014
Published: February 20, 2014

Che-Yu Liu, Kuo-Ju Chen, Da-Wei Lin, Chia-Yu Lee, Chien-Chung Lin, Shih-Hsuan Chien, Min-Hsiung Shih, Gou-Chung Chi, Chun-Yen Chang, and Hao-Chung Kuo, "Improvement of emission uniformity by using micro-cone patterned PDMS film," Opt. Express 22, 4516-4522 (2014)

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