Study of High-Power White LED's Lifetime Based on Accelerated Life Test

Abstract:

The study of LED reliability becomes more and more important with LED widely used in various areas, and accelerated life test (ALT) as an element of reliability test is widely used to predict the lifetime of LED. In this paper, ALTs have been carried out at various current levels and various temperature levels. In the current ALT experiment, three kinds of stressing currents were demonstrated for 1W white LEDs and lumen flux of the tested LEDs were studied, and based on Eyting model, lifetime of the tested LEDs is calculated about 6.86×10⁵h. In the temperature ALT experiment, two kinds of stressing temperature were demonstrated for the same type of white LEDs and lumen flux were also studied, and based on Arrhenius model, lifetime of the tested LEDs is calculated about 7.41×10⁵h. In addition, the color shifting velocity is faster than lumens depreciation velocity was observed in our experiment, which means the lifetime evaluating of white LED should be paid more attention.

• Periodical: Advanced Materials Research (Volume 800)
• Pages: 205-209
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.800.205
• Online since: September 2013
• Authors: De Sheng Li, Nian Yu Zou, Yun Cui Zhang, Xiao Yang He, Yi Yang
• Keywords: ALT, Current, Lifetime, Temperature, White LED

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