失调三反消像散光学系统像差特性

文中以矢量波像差理论为基础，对TMA 光学系统的失调像像差特性进行分析，通过分析发现失调TMA 系统的初级球差在全视场内为常量，彗差在全视场内的方向与量值均为常量，由失调引入的像散表现为失对称性、像散值与视场成线性，其零点位于中心视场。在校正失调产生彗差时，TMA 系统像散零点位于轴上视场，像差接近于零，而边缘视场的像散依然较大，因此在TMA 系统的装调过程中，需要测量多个视场的波像差。在同样情况下若轴上视场测量到像散，则是由于主镜的面形误差导致而非系统失调引起。利用CODE V对失调TMA系统的失调像差分布进行仿真，结果表明，利用矢量波像差理论可以对失调TMA系统的像差进行定性分析，以提高TMA 系统的装调效率。

Misalignment induced aberration characteristic of TMA optical system

Based on the vector wavefront aber ration theory, the misalignment induced aberration's characteristic of TMA optical system was analyses in this paper. It is shown that a misaligned TMA has three residual 3rd aberrations. The 3rd order spherical aberration that is constant over the field and the 3rd order coma is a constant in magnitude and orientation over the field. Moreover, the 3rd order astigmatism is field-asymmetric in orientation and increases linearly with the field, and the location zero for the field-asymmetric, field linear astigmatism always reside at the center of the field of view. It has been demonstrated that a TMA under assembly is only measured to have perfect performance on-axis which is not aligned in any significant way, so the measurements of multiple field points for the TMA are required in the process of alignment. Under condition of remove axial coma, if astigmatism is measured on-axis, which is caused by the primary mirror astigmatic figure error but not the misalignment.