Coupling control of actuators for MEMS-based deformable mirror

Based on the correction of the residual error of wave-front correction, the relationship between the coupling of actuators and correction capability of MEMS-based deformable mirror (DM) is analyzed. When a single actuator of the continuous surface DM works, it creates a displacement at the other actuators, which is described using coupling coefficient (cc). For a MEMS-based DM with a 10×10 actuator array, with the distance between two adjacent actuators (b) being 3 mm, correcting the first 20 Zernike modes, the best coupling coefficient is 10%. Different distances between two adjacent actuators (b) correspond to different correction capabilities and different coupling coefficients. Corresponding to b of 2, 25, 3, 35, and 4 mm, the best coupling coefficient of the DM is 12%, 11%, 10%, 9%, and 8%, respectively.