Mixed lighting based on the linear dimming of three-primary-color LEDs

In order to provide high-quality, intelligent, and healthy lighting sources, a linear dimming hybrid lighting system is constructed using three-primary-color LED light sources. An optimization method for dimming and color mixing is proposed. The light chromaticity and light intensity of the mixed light source are set by color temperature and brightness level, which makes the mixed lighting effect more in line with the demand of "human-centric lighting". In the intelligent optimization of the system, the color temperature is converted into CIE $ {u}'{v}' $ chromaticity coordinates, and the luminance is converted into brightness to make the optimization calculations more accurate. The system adopts the linear dimming method, effectively preventing the health and safety risks caused by light source flicker, and effectively solves the problem of large linear dimming chromaticity drift with an optimization algorithm. Experiments demonstate that the chromatic stability of the mixed light in the hybrid lighting system is maintained within the first step of the CIE ${u}'{v}' $ chromaticity diagram between a color temperature range of 2000 K to 8000 K. Moreover, the system exhibits imperceptible color deviation over the entire range of light intensity adjustments at the corresponding color temperature. This finding also indicate that linear dimming hold a superior edge over pulse-width dimming method in keeping the optical chromaticity stable. Theoretical exploration and experimental results demonstrate that the mixed lighting system is straightforword and practical, with significant practical value.