基于红/绿/蓝/青/黄/暖白6色LED的白光光谱优化方法

提出了一种基于脉冲宽度调制(PWM)的红/绿/蓝/青/黄/暖白(R/G/B/C/Y/WW)6色发光二极管(LED)的白光光谱优化方法。该方法根据光谱叠加性原理,采用1931 CIE-XYZ三刺激值建立了G+WW,B+C,R+Y各混合光源色坐标与光通量贡献率ρG+WW(r1),ρB+C(r2),ρR+Y(r3)的函数关系,在不同光通量百分比r1,r2,r3下,通过优化遍历范围计算得到相关色温为2700,4000,5500,7000 K时合成白光的最优显色指数Ra为96.4,97.0,97.3,97.4,并采用R/G/B/C/Y/WW 6色LED进行实验验证。结果表明:R/G/B/C/Y/WW LED模块可实现相关色温在2700~7000 K范围内的白光调节。当光通量设定为500 lm时,相关色温的最大相对误差为1.96%,一般显色指数Ra最大相对误差为1.24%,发光效率可达146.81~152.40 lm·W-1。

Spectral Optimization of a Mixed White Light-Emitting Diode(LED)Cluster Comprising a Red/Green/Blue/Cyan/Yellow/Warm White LED

In this paper,a spectral optimization method for a mixed white light-emitting diode(LED)cluster comprising a red/green/blue/cyan/yellow/warm white(R/G/B/C/Y/WW)LED based on pulse width modulation(PWM)is proposed.Following the principle of the spectral combination of multicolor LEDs,the proposed method adopts the 1931 CIE-XYZ tristimulus value to determine the relationship between the color coordinates and the contribution ratioρG+WW(r1),ρB+C(r2),ρR+Y(r3)for each component,i.e.,G+WW,B+C,and R+Y,respectively.Using an optimized traversal range under different flux contribution ratios,i.e.,r1,r2,and r3,a maximum color rendering index(Ra)of 96.4,97.0,97.3,and 97.4 is attainable when the correlation color temperatures(Tc)of the synthesized white LED cluster are 2700,4000,5500,and 7000 K,respectively.Furthermore,experimental verification was conducted with R/G/B/C/Y/WW LEDs.Results show that an R/G/B/C/Y/WW LED module can realize tunable white light in a wide range of Tc(2700--7000 K).When the luminance flux is set to 500 lm,the maximum relative errors of Tc and Ra are 1.96%and 1.24%,respectively,and the luminous efficiency varies in the range 146.81--152.40 lm·W-1.