液晶电视用LED背光源的热特性与光色特性之间的关系

本文研究了温度对LED背光源的影响,发现温度高的地方,LED的亮度衰减较快,且红、绿、蓝三色LED亮度的衰减速度是不一致的,其中红光LED衰减最快,导致LED背光源的色度偏移,色温均匀性变差,严重影响背光源的颜色表现能力.此外,通过对直下式LED背光源的热分布与其亮度和色温变化情况的研究,发现温度较高的地方,亮度衰减得快,色温也上升得快；而侧光式LED背光源的光色分布主要受到导光板的影响,所以不能直观地观察到其与热分布的关联性.

The Relationship between Thermal and Photometric Characteristics of LED Back Light Applied in LCD

The effect of temperature on LED back light is researched. We find that the luminance of LED decays quickly in high temperature areas, thus the degradation rate of RGB tricolor LED luminance is inconsistent, which of red LED is the fastest, resulting in color offset, color temperature uniformity becoming worse and seriously affecting the color performance of back light. In addition, through study of direct type LED backlight＇s temperature distribution and its variation of luminance and color temperature, we find that the luminance decays quickly and color temperature also rises quickly in high temperature areas. While, the luminance and color distribution of side type LED back light are mainly affected by the light guide plate, so we cannot directly see its correlation with heat distribution.