高显色指数LED合成白光光源的研究

Study on LEDs Synthesized High Color Rendering Index White Light Source

针对目前白光发光二极管(LED)照明灯具显色性不高的问题,基于测色法研究了LED合成白光显色指数的计算模型,根据参与合成的LED光源光谱及其数量,软件编程计算得出合成光源的色温、显色指数等参数。采用优化的遍历范围,将实验测量得到的冷、暖白光及单色LED的光谱导入程序进行模拟计算,得到不同色温下合成光源的显色指数最大值以及所对应的各种LED配比数量。结果表明,暖白光LED与红、绿、蓝LED合成可以获得色温T_c介于3500 K^12300 K、显色指数R_a介于92.0~97.7的白光;与红、绿、青LED合成可以获得R_a介于95.0~97.8的低色温白光(3500 K^4500 K)。冷白光LED与红、绿、青LED合成可以获得R_a介于90.9~98.4的高色温白光(8200 K^13000 K)。对理论计算的T_c=7803 K、R_a=97.29的LED配比进行实际制作,实验测量得到T_c=7992 K,R_a=97.1,理论计算结果与实验结果吻合。

Targeting poor color rendering property of current white light-emitting diode （LED） lamps, based on the colorimetry method, the calculation model for color rendering index of synthetic white light is studied and the parameters like color temperature and color rendering index of the synthetic LED light source are obtained based on the spectrum and quantity of light sources involved in the synthesis process. By using optimized traversal range, the spectra of cold and warm white light and single- color LEDs are imported into the program for simulating calculation, obtaining the maximum value of color rendering index of the synthesized light source under different color temperatures as well as corresponding matched quantity of various LEDs. The results show that the synthesis with warm white LEDs and red, green and blue LEDs can lead to white light whose color temperature falls in the range of 3500 K-12300 K and color rendering index Ra ranges between 92.0 and 97.7. The synthesis with warm white LEDs and red, green and bluish-green LEDs can lead to low color temperature white light （3500 K-4500 K） whose color rendering index Ra ranges between 95.0 and 97.8. The synthesis with cold white LEDs and red, green and bluishgreen LEDs can lead to high color temperature white light （8200 K-13000 K） whose color rendering index Ra ranges between 90.9 and 98.4. An actual fabrication is conducted following the calculated LED amount to produce an LED module with 7803 K color temperature and 97.29 color rendering index. Actual measurement shows that the produced LED module has a color temperature of 7992 K and a color rendering index of 97.1, which is well matched the theoretical results.