Optimized structure parameters of deformable mirrors for wavefront correction in a high power laser system

A new deformable mirror structure is presented, which mainly consists of a mirror, some transition layers, a preload structure and PZT actuators. Compared with the conventional deformable mirror, the new structure can smooth the surface shape and reduce residual errors, which are mainly affected by some structure parameters. The finite-element method is used to analyze the relationship between the structure parameters and the residual errors. The simulation results show that the structure parameters, including the diameter, thickness, and materials of transition layers and the stiffness of preload springs, can determine the residual errors. Based on the simulations, experimental comparisons between new and conventional deformable mirrors have verified that the new structure can effectively diminish residual errors. The new structure deformable mirror will play an important role in high power laser aberration correction.