Analysis of real-time modal reconstruction algorithms for adaptive optics system

摘要

Three kinds of real-time wave-front reconstruction algorithms used in adaptive optics (AO) systems, the direct-gradient algorithm, the mirror-eigen modal algorithm and the sensor-eigen modal algorithm, were analyzed in this paper. The direct-gradient reconstruction algorithm was compared with other two modal reconstruction algorithms in experiments. The mirror-eigen modal algorithm was based on the modal functions gotten by orthogonalizing the coupling matrix between actuator influence functions of deformable mirror. The sensor-eigen functions were deduced by orthogonalizing the correlation matrix between Hartmann-Shack wave-front sensor and deformable mirror. The functions were used as basic modes in a novel modal reconstruction algorithm. All these three algorithms were tested on a 61-element AO system in atmosphere turbulence. The experiment data proved that the performances of AO system could be improved by using the two modal algorithms compare to those using the direct-gradient algorithm in the same work condition.