大功率LED整个寿命中的颜色漂移

为了研究大功率白光、蓝光LED在整个寿命中的颜色漂移,选用一系列的大功率白光、蓝光发光二极管分别进行了不同电流的恒流点亮。在点亮不同时间阶段测量了LED的发射光谱、色坐标和色温,研究了在不同电流点亮时的光通量、色坐标和色温的变化,分析了电流、时间等因素对颜色漂移的影响。结果表明,在不同电流点亮及同一电流点亮的不同时间阶段,LED的颜色不同。说明大功率LED的颜色漂移不仅是由荧光粉老化所引起,更主要的因素是材料本身的变化。文章对此进行了初步的分析,为白光LED的应用及进一步研究白光LED颜色漂移提供了参考。

Color Offset in Process of High-Power LED Life Aging

To study color offset in the process of high-power LED life aging, a series of power white and blue LEDs are lighted continuously under invariable current respectively. Emission spectra, color coordinates and color temperature are measured at different period. Their changes are researched. Based on the analysis of cause of color offset, the result is that the color of LEDs are different at different period with the same current and different current lighting. It indicated that the colour offset of high-power LEDs are caused not only by aging of phosphors, but also due to the changes in the material itself. The results will provide a reference to the application of white LED and for the further study.