Color Offset in the Process of High-Power LED Life Aging

Abstract:

In order to study color offset of the high-power white light and blue light LED in the whole life, a series of high-power white light and blue light emitting diodes are lighted continuously under a constant current. In the light of different period of time, measured the light emitting diode emission spectrum, color coordinate, color temperature of the light emitting diodes are measured at different periods; light luminous flux, color coordinate and color temperature changes are also measured under different currents. The experimental results show that the color of LED is different at different period under the same current, and is also different under a variable current. The article studied the influence of different factors on the color offset, and pointed out that the high-power LED color offset is caused by not only phosphors aging but also more major changes of the material itself. Furthermore, the results will provide a reference to the application of white LED and for the further study.

• Periodical: Key Engineering Materials (Volume 693)
• Pages: 498-503
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.693.498
• Online since: May 2016
• Authors: L.Y. Zhang*, Y.P. Cui, Z.N. Luo, L. Zhou
• Keywords: Color Offset, Emission Spectrum, High-Power LED, Life Aging

References

[1] Liu Xingren, Guo Guanghua, Lin Xiuhua. Driving Current Dependence of Emission Spectra and Spetro-colour Characteristics in InGaN Based LED [J]. Zhaoming Gongcheng Xuebao, n3, pp.14-18, March, (2004).

[2] Shuji Nakamura. InGaN-based Blue Light-emitting Diodes and Laser Diodes [J]. Journal of Crystal Growth, 201/202, pp.290-295, (1999).

DOI: 10.1016/s0022-0248(98)01344-x

[3] Fang Fubo, Wang Yaohao, Song Daihui, Yu Binhai. Spectrum Analysis of White LED Decay [J]. Chinese Journal of Luminescence, v129, n12, pp.353-357, April, (2008).

[4] Liu Jie, Sun Jiayue. The Development of the White Converter Based on LED [J]. Huaxue Tongbao, n6, pp.417-421, June, (2005).

[5] F. Rossia, N. Armania, G. Salviatia，etc. The Role of Mg Complexes in The Degradation of InGN-based LED [J]. Superlattices and Microstructures, n36, pp.859-868, (2004).

[6] F. Manyakhin, A. Kovalev，A. E. Yunovich. Aging Mechanisms of InGaN/AlGaN/GaN Light-emitting Diodes Operating at High Currents[J]. MRS Internet Journal of Nitride Semiconductor Research, n3, p.53, March, (1998).

DOI: 10.1557/s1092578300001253

[7] Liu Xijuan, Wen Yan, Zhu Shaolong. Definition and Testing Method of the Lifetime of White LED [J]. Lamps & Lighting, n4, pp.16-22, April, (2001).

[8] Grzanka S, Franssen G, Targowski G, etc. Role of The Electron Blocking Layer in The Low-temperature Collapse of Electro-luminescence in Nitride Light-emitting Diodes [J]. Appl. Phys. Lett. , 2007, 90 (10): 103507-1-3.

DOI: 10.1063/1.2711765

[9] Lee Sung-Nam, Cho S Y, Ryu H Y, et al. High-power GaN-based blue-viote diodes with AlGaN /GaN multiquantum barriers [ J ]. Appl. Phys. Lett. , 2006, 88 (11): 111101-1-3.

DOI: 10.1063/1.2185251

[10] Luminescence Spectra, Efficiency, and Color Characteristics of White-Light-Emitting Diodes Based on p–n InGaN/GaN Heterostructures with Phosphor Coatings [J]. Semiconductors, v40, n6, pp.739-744, June, (2006).

DOI: 10.1134/s1063782606060212

[11] Zhang Louying, Zhou Li. Research on Mechanism of High-power LED Luminous Attenuation [J]. Semiconductor Technology v34, n5, pp.474-477, Spring, (2009).