对水平对称式Ebert-Fastie型光谱仪的参量及性能进行了分析研究.基于水平对称式Ebert-Fastie型光谱仪工作时的光路图，用几何方法推导出了入射光线与衍射光线的夹角、入射角、衍射角、可测光谱级次及波长适用范围的计算公式，该公式可通过简单编程计算结果.基于理论分辨率计算公式，并考虑到狭缝宽度导致实际分辨率低于理论分辨率，推导出了分辨率与狭缝宽度等结构参量之间关系的计算公式，对该公式求导得出提高分辨率的方法，并举例计算得出考虑狭缝宽度后的实际分辨率为理论分辨率的83％.

The parameters and property of Level symmetrical Ebert-Fastie spectrograph was studied.Based on the light-path diagram of Level symmetrical Ebert-Fastie spectrograph,it was deduced for the calculating equations of included angle between incident light and diffracted light,angle of incidence,angle of diffraction,measurable spectrum grade and measurable range of wavelength,by geometry methods.Based on theoretical resolution’s calculating formulas,the equations of interaction between resolution and structure parameters was deduced in view of slit width.By deriving the equations,improving resolution’s methods were come into being.The example of calculating revolution shows that the practical revolution in view of slit width is 83% of the theoretical resolution in which slit is infinitely slender.