Abstract
This paper makes a study and experimental analysis on luminous efficiency of white LED in terms of thermal efficiency, and arrives at a conclusion that an increase in temperature corresponds to an increase in thermal efficiency of LED. The paper also illustrates this phenomenon with a careful theoretical analysis and makes it clear that the reason of this phenomenon is that internal quantum efficiency and external quantum efficiency decrease when operation temperature increases. LED will not work well in an excessive high operation temperature and a visible light decay comes. A stress deformation which is beyond retrieve will appear on the encapsulating material of LED and it may make internal circuit of LED a break when operation temperature is excessive high, so good heat dissipation system will make the LED at a stable performance and a long operating life.
Keywords:White LED ; Luminous efficiency; Thermoresistance; Temperature