基于RGBW四色LED的混光研究

Research on Color Mixing Based on RGBW-LEDs

根据RGBW四色混光方程组,结合脉冲宽度调制法的特点推导出占空比与色品坐标的函数关系。借助Matlab软件对混合光的光效和一般显色指数进行多元约束条件下寻优,并通过实验验证。结果表明:RGBW光源模块可实现2703 K^7692 K色温范围的白光,优化目标为显色性能最佳时,混合光的一般显色指数高达95,在光效最大的优化目标下,混合光可以实现108 lm/W的高光效。为了使光源模块同时具有优良的光效和显色性能,提出对光效和一般显色指数同时进行寻优。模拟实验表明:适当降低光效可以显著提高显色性能;降低显色性能同样可以改善光效。通过平衡光效和显色性能,可以实现一般显色指数大于90且适用于多数场所的高光效白光。

A functional relationship between chromaticity coordinate and the duty cycle based on the RGBW color mixing equations and the pulse width modulation drive （PWM） is deduced. Multi-constraint optimization simulation of the luminous efficacy of source （LES） and color rendering index of the mixed-light is carried out on a Matlab program, which is further verified by the experiments. The results show that the RGBW light source can produce a wide range of color temperature from 2703 K to 7692 K. Under the highest Ra achievable, the Ra reaches 95, while the LES can reach 108 lm/W under the condition of an optimized LES. Furthermore, by reducing the color rendering index, the luminous efficiency improves significantly. The color rendering index likewise increases by reducing the luminous efficiency. By balancing these two factors, it has found that RGBW light source with high LES and Ra over 90 can best satisfy the demand of the current lighting manufacturing.