We report the laboratory experiment on a segmented mirror testbed that shows the use of a dispersed Rayleigh interferometer to phase segmented mirrors. Segment alignment of tip-tilt is fulfilled by overlapping diffraction pattern centroids of the three individual segments on the focal plane. A spherical interferometer is introduced to evaluate the performance of piston, tip-tilt sensing, and control closed-loop, and finally a total residual root-mean-square (RMS) surface error of about 45 nm is achieved, in which a typical error of about 20 nm is contributed by piston. These results demonstrate that the dispersed Rayleigh interferometer can successfully sense the piston of segmented mirrors and be used in phasing segmented telescopes under extensive studies.

总结了常用的共相位检测方法，分析了各种方法的特点及其用于空间望远镜在轨检测的适用性。提出了一种新的基于色散瑞利干涉原理的共相位误差检测方法和相应的干涉条纹数据处理方法——二维色散条纹分析法。介绍了色散瑞利干涉法的基本原理，给出了其检测拼接主镜望远镜共相位误差的光路图。为验证所提出的方法，搭建了一套色散瑞利干涉仪检测共相位误差的实验验证装置。初步的实验结果表明所搭建的色散瑞利干涉实验装置的量程可达到200 μm，多次测量值的均方根误差(重复性)优于2 nm，共相位误差δ≤1 μm时，测量精度为6.56 nm，可以满足空基分块主镜望远镜在轨共相位检测的要求。