采用基于高亮度白光LED的色温可调混色方法，通过实验与理论计算研究了不同色温白光LED混色后色温Tc及显色指数Ra的变化。采用低色温(2800～3000K、3000～3400K)和高色温(7000～8000K)三种白光LED样品进行串联和并联混色，通过控制正向工作电流研究混色后白光的调光效果及显色指数变化。实验与计算表明：混色后白光色温可以实现在3000～7000K可调；选取Ra>66的低色温白光LED与Ra>87的高色温白光LED进行混色，可以在色温可调范围内得到Ra>75的较好显色指数的白光。

The color temperature (Tc) and color rendering index (Ra) were analyzed by experiments and theories after mixing high-brightness white LEDs with different color temperatures. Two white LED samples with low color temperature (2800～3000K and 2800～3000K) and one with high color temperature (7000～8000K) were mixed in series and parallel. The dimming effect and color rendering index were analyzed by changing the forward current. The results show that the tunable range of color temperature of mixed white LEDs is 3000K～7000K, and when white LEDs with Ra> 66 are mixed with LEDs with Ra> 87, white light with Ra>75 can be obtained in the tunable range of color temperature .