在光学系统装调中, 由于光学元件的面型误差、加工误差等影响因素的存在, 使待装调的光学系统的装调失调量并非为一个确定的准值, 而是一个范围值, 在失调量范围内, 可能存在不止一组Zernike系数符合要求, 即以像差值为判据的装调结果的解不唯一, 需要对光学系统的其他参数进行测试判断光学系统在装调阶段是否满足技术要求。介绍了一种在装调过程中, 当各项像差的Zernike系数接近设计时, 利用干涉仪、分划板、五棱镜、经纬仪等设备, 在波前测试光路中采用猫眼效应进行装调过程中的光学系统焦距的测试方法, 通过光学系统的波像差和焦距值两种测试结果判断装调工作是否符合要求。经过实际装调过程中的应用验证了该方法的有效性, 在光学系统的装调过程中将焦距值控制在±0.5%以内。

In the alignment of optical systems, due to the wavefront errors, artifactitious error et al, the misalignment of the optical systems to be aligned is not a exact value but a range. In the misaligned range, there are more than one group of Zernike coefficient satisfy the requests of the optical systems. The solver of aligned result judged by wavefront errors is not unique. The alignment of optical systems need measurements on other parameters to estimate if the alignment work is satisfied with requests or not. A focal length measuring method in the process of the alignment of optical systems is introduced. The method is based on the cat eye effect in the wavefront measuring rays of the optical systems alignment, the method use instruments like interferometer, target plane, pentaprism, theodolite et al. To estimate the alignment results by the wavefront errors and focal length of the optical system, the efficiency is proved in practical optical systems alignment. The focal length result is controlled by ±0.5% of the focal length in the alignment of optical systems.