Influence of coupling coefficient on sparseness of slope response matrix and iterative matrix

Based on a 529-actuator adaptive optic (AO) system, the sparseness of slope response matrix from deformable mirror to Hartmann wavefront sensor and the sparseness of iterative matrix in wavefront reconstruction are analyzed. The influence of actuator coupling coefficient on the slope response matrix sparseness, the iterative matrix sparseness, and the AO system correction quality are also studied under the condition of constant actuator spacing. Larger coupling coefficient results in a lower sparseness of slope response matrix and an iterative matrix. Too large or too small coupling coefficient will lead to lower stability and correction quality of AO system. Finally, the optimal range of coupling coefficient is provided by the balancing correction quality, sparseness of slope response matrix, and stability.