Design and Research of Large-Scale Curvature Adjustment Optical Mirror

This study introduces an optimization design method for large-scale curvature-adjustable optical mirrors, innovatively integrating parametric modeling with the optimized layout of actuators, targeting the achievement of extensive curvature adjustability and high-precision surface correction for segmented mirrors. The optimization objective is based on the surface figure residual when the curvature radius of the segmented mirror is altered by 100 mm. Through the optimization of the number, arrangement, and thickness of reinforcement ribs of the actuators on the back of the segmented mirror, a parametric model of a segmented mirror with an edge-to-edge distance of 510 mm and a radius of curvature 9100 mm is developed. Simulation outcomes reveal that a 0–15 μm variation in the actuators results in a curvature radius change of 178.45 mm in the segmented mirror, with a highly linear correlation, achieving a radius of curvature reconfiguration of the primary mirror in the optical system from 9100 mm to 9000 mm, with a residual surface figure error of less than 10 nm. The experimental results indicate that within a 0–15 μm closed-loop stroke range, the curvature radius of the segmented mirror can be adjusted by 146.89 mm, fulfilling the design objective of a lightweight mirror with a significantly adjustable curvature radius. This research is anticipated to offer technical support and serve as a reference for the assembly, adjustment, and inspection of large-aperture segmented mirrors, as well as for the curvature radius variation in multiple segmented mirrors, thereby holding substantial practical value in engineering applications.