Method to compensate for pupil image motion of a solar telescope with adjustment of a secondary mirror

Structural deformation-induced pupil image motion poses a significant challenge for large-aperture ground-based telescopes. This paper presents an innovative fast building and validating look-up table method to compensate for pupil image motion utilizing hexapod-controlled secondary mirror adjustment. Through comprehensive numerical simulations and experimental validation, the correction capability of this approach has been examined. Theoretical analysis and simulation results demonstrate that this correction technique effectively compensates for primary-secondary mirror misalignment. During the experiment, the pupil image precisely locates at the wavefront sensor (WFS) center, with a maximum position deviation of 3% of the field of view and WFS detection to the pixel level. This approach, which integrates simulation analysis with experimental verification, offers several advantages, including structural simplicity, rapid pointing data acquisition, fast precise validation, and operational ease, indicating substantial potential for application in astronomical observation systems.