Interferometric null testing and the model for separating adjustment errors

Performing objective and accurate evaluation on the figure errors during polishing is one of the key factors to realize fast, deterministic manufacture for large optical off-axis aspheric mirrors. In consideration of the special processes of aspheric, an applicable null corrector is designed and optimized based on the indexes of each component. Furthermore, based on the interferometric testing system, an analysis on the testing accuracy of the designed null corrector focused on the adjustment errors is made, and errors separating matrix is established. At last, interferometric patterns corresponding to different adjustment errors are achieved by simulation. Simulation results would be helpful to adjust the relative position between the corrector and mirror.