Share Email Print
cover

Proceedings Paper

Accelerated life test for high-power white LED based on spectroradiometric measurement
Author(s): Haiping Shen; Jiangen Pan; Huajun Feng
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We implement an accelerated life test for the high-power white LEDs based on spectroradiometric measurement. The luminous flux degradation performances are investigated at both the rated current of 350mA and a higher current of 500mA. The average lifetime of the LEDs is 7057 hours at 350mA and 3508 hours at 500mA. The variations of the color of the white LEDs are studied. The color of the low quality white LEDs changes greatly, while the high quality white LEDs keep their color stable. The degradation performances of the chip and phosphor are studied separately. The quantum efficiency of the phosphor becomes lower from 350mA to 500mA current supply. The LED chip degrades faster than the phosphor during the 500mA high current aging. The luminous flux increase and the peak wavelength shift from 350mA to 500mA current supply are found to be useful lifetime indicating parameters that correlate well to the reliability of the high-power white LEDs.

Paper Details

Date Published: 4 January 2008
PDF: 9 pages
Proc. SPIE 6841, Solid State Lighting and Solar Energy Technologies, 684104 (4 January 2008); doi: 10.1117/12.755708
Show Author Affiliations
Haiping Shen, Zhejiang Univ. (China)
Jiangen Pan, Everfine Photo-E-Info Co., Ltd. (China)
Huajun Feng, Zhejiang Univ. (China)


Published in SPIE Proceedings Vol. 6841:
Solid State Lighting and Solar Energy Technologies
Jinmin Li; Ling Wu; Yubo Fan; Yong-Hang Zhang; Michael E. Coltrin; Yuwen Zhao; Nuofu Chen; Vladimir M. Andreev; Jai Singh, Editor(s)

© SPIE. Terms of Use
Back to Top