Determination of limited freedoms for restoration error correction of segmented mirrors in space

It is the only way to adapt the deployable and segmented mirrors for space telescope with large aperture and high image resolution. Owing to the restoration error, the deployed segmented mirrors would yield piston error and figure error which will degrade the optical performance. How to determine the limited freedoms for correction of restoration error is very important. The influence of the restoration error of segmented mirrors to figure error is studied by computer simulation. The results show that the restoration error not only depends on the accuracy of the deployable mechanism, but also depends on the geometric parameters of the segmented mirrors.