由于系统装调与器件定位精度的限制，空间调制傅里叶变换光谱仪中的两个多级微反射镜在对准过程中会产生相对位置的平移和旋转。为了明确对准误差对系统产生的影响，利用线性系统理论与标量衍射理论分别建立了平移误差与旋转误差对应的干涉图像与复原光谱的模型。通过对计算结果的分析，平移误差与旋转误差均会对边缘的干涉图元进行剪裁，从而在复原光谱中引入伴线，带来光谱噪声。根据平移误差与旋转误差对干涉图像的作用特点，提出一种对干涉图像进行区域补偿的方法，通过扩展多级微反射镜的阶梯级数扩大干涉区域，然后利用干涉图像内部有效的干涉图元进行光谱反演；计算表明该方法可以有效抑制对准误差给系统带来的影响，从而降低多级微反射镜的定位精度要求。

Due to the precision restriction of the system assembling and device location, the relative position of the two stepped micro-mirrors in spatial modulation Fourier transform spectrometer can appear the shift and rotation in the alignment process. Using the linear system theory and scalar diffraction theory, the model of the interferogram image and recovered spectrum corresponding to shift error and rotation error are established respectively. By means of the analysis to the calculation result, the marginal interferogram units are clipped by the shift error and rotation error, and the concomitant spectrum lines is appeared in recovered spectrum, bringing the spectrum noise badly. Finally, according to the action characteristics of the shift error and rotation error to interferogram image, a method of regional compensation to interferogram image is put forward, by extending the step number of two stepped micromirrors to expand the interference area, then using the internal effective interferogram units to recover the signal spectrum. Calculation shows that this method can restrain the influence of the alignment error effectively, and so as to decrease the location precision of the stepped micro-mirror consumedly.