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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 17, Iss. 8 — Apr. 13, 2009
  • pp: 6148–6155

Azimuthally isotropic irradiance of GaN-based light-emitting diodes with GaN microlens arrays

Mount-Learn Wu, Yun-Chih Lee, Shih-Pu Yang, Po-Shen Lee, and Jenq-Yang Chang  »View Author Affiliations

Optics Express, Vol. 17, Issue 8, pp. 6148-6155 (2009)

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In this paper, the irradiance-modifying concept is proposed by introducing a microlens array on the p-GaN layer of GaN-based light-emitting diode (LED). Every microlens can locally modulate photons emitting from a micro-scaled active region of multiple quantum wells (MQWs) just beneath the microlens. The azimuthally isotropic irradiance from the GaN-based LED with microlens arrays is demonstrated numerically and experimentally. To realize such a novel LED, one-dimensional GaN microlens array with a period of 1.6 μm and a filling factor of 0.64 are fabricated by using dry etching. According to experimental results, the azimuthally isotropic light emission of proposed LED is observed. By using the angular-resolved photoluminescence, its intensity variation corresponding to the azimuth angles is as low as 10% within the angle region of ±50°.

© 2009 Optical Society of America

OCIS Codes
(230.3670) Optical devices : Light-emitting diodes
(230.3990) Optical devices : Micro-optical devices

ToC Category:
Optical Devices

Original Manuscript: January 15, 2009
Revised Manuscript: March 21, 2009
Manuscript Accepted: March 31, 2009
Published: April 1, 2009

Mount-Learn Wu, Yun-Chih Lee, Shih-Pu Yang, Po-Shen Lee, and Jenq-Yang Chang, "Azimuthally isotropic irradiance of GaN-based light-emitting diodes with GaN microlens arrays," Opt. Express 17, 6148-6155 (2009)

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