为实现液晶显示中背光源的色域扩展和白平衡，本文基于CIE1931色度学系统，研究了光致发光量子点背光源的混色理论，采用高斯函数拟合光谱曲线，构建了量子点背光源的光谱函数模型，提出了量子点光谱与色坐标之间的互转换方法，最终实现背光源的白平衡。首先，在保持光谱有效信息的基础上，将复杂光谱数据拟合为拟定参数的高斯函数叠加; 然后，根据CIE1931XYZ系统的色坐标求解光谱分布函数及其高斯参数。实验以色温为5 560 K、6 500 K和10 000 K的量子点背光源作为基准进行了白平衡的理论验证，得到了光谱分布函数并评价了量子点背光源的白平衡颜色特性，验证了其光谱和色坐标之间准确而高效的互转换，简化了光谱曲线的基本函数形式和数值计算量，实现了数据压缩，对实现量子点背光源的白平衡实验提供了必要的技术依据和理论指导。

In order to realize color gamut extension and white balance of backlight source in liquid crystal displays, this paper researches light mixing theory of quantum-dot backlight in CIE1931 chromaticity system by using Gaussian curve fitting spectrum, and establishes spectral function model of quantum-dot backlight source, and further proposes a conversion method between quantum-dot spectrum and color coordinates. First, based on maintaining effective spectral information, the complex spectral data is fitted to conform to the superposition of Gaussian function. Then, color coordinate calculated by CIE1931XYZ system is used to solve spectral function and Gaussian parameters. Finally, the white balance of backlight source can be achieved. Experimental verification achieves the spectral power function and analyses the color characteristics of quantum-dot backlight with color temperature of 5 560 K, 6 500 K and 10 000 K as a reference. Accurate and efficient mutual conversion between the spectrum and color coordinate can be achieved. These results simplify the form of spectral function and numerical computation, achieve the data compression, and provide a necessary technical basis and theoretical guidance for white-balance experiment of quantum-dot backlight source.