The Study On Key Technique Of SPGD AO Controlling And Displaying System With Master-slave Structure

Adaptive Optics (AO) is a new subject researching the real-time and automatic improvement of light wavefront quality. Optimization Adaptive Optics corrects the aberrations by optimizing the performance metric of the system. The fast convergence speed of Stochastic Parallel Gradient Descent (SPGD) algorithm makes it possible for SPGD AO system to realize real-time correction of light wavefront and have great application potential. In addition, SPGD AO system avoids a series of troubles which are encountered in the adaptive optics systems based on wavefront measurements and has a simple and compact system architecture with low cost. Therefore, it has become a research focus in adaptive optics field these years.This paper investigates the basic theory of SPGD AO technique and establishes the numerical model of SPGD AO system to study its convergence character. A new definition of convergence speed is introduced and the selection of the perturbation amplitude and the gain factor is primarily discussed. The working principle of an existing SPGD AO system is studied and its iteration rate is analysed and experimented. It is found that the PCI A/D sampling and PCI digital communicating boards are the main limitations of the working speed of the system. A more functional SPGD AO system with master-slave structure is then built based on PC controller and laborary conditions. It can work at a speed close to the time response limitation of the deformable mirror. The main function of the system are enhanced, a new controlling program for displaying and operating is developed. Experimental results of static and simulative dynamic correction show that the system has good correction ability.