在测试仪器中，单色器的光谱纯度决定系统的分辨率。对瓦茨沃斯棱镜系统与切尔尼—特纳光栅系统进行分析，提出了影响单色器光谱纯度的六种主要因素，建立了函数关系，并对综合作用进行了评价。 In test equipment, the spectral purity of the monochromator determines the resolution of the system. Analyzed the Watson prism system and the Cherni -Tarner grating system, proposed six main factors that affect the spectral purity of the monochromator, established the functional relationship, and evaluated the comprehensive effect.