分析了在激光助视下，景物反射辐射光谱与光电阴极光谱匹配系数的变化，给出了理论公式，分析了此系数的特征和意义．计算了激光助视下光谱与几种典型的超二代管光电阴极(New S₂₅，Super S₂₅₁，Super S₂₅₂)的光谱匹配系数，其结果分别为0．833、0．72和0．56．验证了选取激光助视系统光源的合理性，揭示了在激光助视下，光谱匹配系数的特征，同时为在激光助视下夜视系统的视距评估提供了重要参考．

The change of spectral matching factors between photo cathode and reflecting spectrums of scenes is analyzed,when the laser aids system is used. Its expression is given,and the character and significance of the expression are analyzed. The spectral matching factor is calculated between the Super Second Generation Photo Cathode(New S₂₅,Super S₂₅₁,Super S₂₅₂) and scenes by the laser. And the results are 0.833,0.72 and 0.56,which proves the laser(λ=850 nm) is reasonable. The character of matching factor under laser aids is discussed and analyzed. All of above is with practical value in the evaluation of visual range of night vision systems when the laser aids system is used.