系统分析了迈克尔逊干涉光谱仪中平面动镜在运动过程中发生倾斜致使反射光束偏转时对干涉图的影响.结果表明,光束偏转带来的误差分为三部分：光束偏转导致整体增加的恒定光程差,垂直光轴方向因不同光线而引入的偏移光程差以及偏转光束中心相对于光轴的偏移量.从调制度和相位误差角度给出了平面动镜倾斜误差容限,并讨论了减小干涉图受光束偏转影响的方法.

The tilt tolerance of the plane moving mirror in the Michelson interferometric spectrometer were systematically analyzed by means of modulation depth and phase error with rectangular aperture being concerned.It is found that the changes resulted from the inclination of the moving mirror consists of three parts： the stationary OPD due to the optical beam deflection,the offset OPD due to the different ray in the direction perpendicular to the optical axis,and the offset from the center of the deflected beam to the optical axis.The formulae of the tilt tolerance were derived,the methods solving the problems resulted from the inclination of the moving mirror were discussed.