Abstract: In order to improve the comfort degree of indoor lighting source, an implementation method of color temperature adjusting lighting system is proposed, which meets the people’s demand for adjusting color temperature and brightness according to their physical and psychological needs in different environments. According to the coordinates of red, green, blue colors and blackbody track, the desired brightness of the three primary colors which matches the target color temperature on the basis of the light mixing arithmetic is calculated. Then the gray data is acquired by PAM or PWM gray modulation mode, and the feasibility of the method is verified by experiments of several typical color temperatures, and finally the causes of errors are analyzed. The experiment results show that this method can not only realize the matching of target color temperature of different brightness, but also the color temperature and the brightness can be modulated on a great scale.

Key words: color temperature, adjustment, gray modulation, lighting system