拼接误差对拼接式大口径反射镜成像质量的影响

以由七片边长为0.5 m的正六边形子镜组成的拼接式大口径反射镜为例,理论分析和数值模拟各种拼接误差对成像质量的影响.利用傅里叶变换的特殊性质简化求解大反射镜的点扩散函数过程并推导各种误差下的解析表达式.采用快速傅里叶变换数值模拟边缘失配误差、平移误差及倾斜误差情况下的点扩散函数,并根据光学系统的成像原理模拟成像效果.结果表明,边缘失配误差对成像质量无影响,而平移误差影响较大,倾斜误差影响相对较小.

Influences of the Alignment Errors on Image Quality of Large Segmented Mirrors

Influences the alignment errors on the image quality of the large segmented mirror are theoretically analyzed and numerically simulated formed by seven hexagonal segments in the thesis.By employing the properties of the Fourier-transform,an analytic Fourier-transform method is presented that can be used to deduce the point-spread-functions of the segmented mirror with alignment errors.Based on the Fast-Fourier-transform technique,the point-spread-functions in the presence of edge misconfigure,transverse excursion,and tilt errors on an individual segment are simulated.And the image qualities are numerically simulated according to the imaging principle.It is revealed that the edge misconfigure errors almost have no influence on the image qualities,but the influences due to the transverse excursion errors are relatively intensive in comparison with that due to the tilt errors.