Optimum matching of wavefront sensor and wavefront corrector

In an adaptive optical system, the effectiveness of wavefront correction is influenced by relative configuration (matching) of the subapertures of the wavefront sensor and actuators of the wavefront corrector. In this paper, the computer simulations for the systems using Hartmann-Shack wavefront sensor, deformable mirror with continuous face plate, and discrete actuators are reported. In the simulation we use the algorithm of direct wavefront slope control. For different configurations of wavefront sensor and wavefront corrector, the wavefront reconstruction matrixes are established based on the measured influence function of deformable mirrors developed in the Institute of Optics and Electronics. The process of wavefront sensing, reconstruction, and correction for different Zernike terms and a series of wavefront induced by Kolmogorov turbulence are simulated. The criteria for evaluating the configurations are residual error of correction and stability of reconstruction matrix (condition number). The results of this investigation show that the configurations in which each subaperture is controlled mainly by three actuators have smaller residual error and better stability. The arrangements of square subaperture with 4 actuators at the corners are unstable and result in a checkerboard pattern of residual wavefront.