Comparative assessment of three algorithms to control a deformable mirror for an adaptive optics system with no wavefront sensor

The images obtained from confocal imaging systems present less resolution than the theoretical limit due to imperfection of the optical components and their arrangement. This imperfection deteriorates the wavefront and introduces aberrations to the optical system. Adaptive optics (AO) systems composed of a wavefront sensor (WFS) and a deformable mirror represent the most used solution to this problem. Such adaptive optics systems are expensive. In addition, in microscopy, WFSs cannot be used due to stray reflections in the system and high aberrations introduced by the specimen. For these reasons, sensor-less AO systems have been developed to control the deformable mirror (DM) using an optimization algorithm in an iterative manner. At each iteration, the algorithm produces a new set of voltage and sends it to the mirror so as to optimize its shape, in such a way, as to maximize the strength of the photodetector current in the imaging system. In this paper the results of the application of three optimization techniques in the sensor-less AO are compared. The three optimization techniques are simulated annealing (SA), genetic algorithm (GA) and particle swarm optimization (PSO). SA and GA have been previously implemented and PSO is explained in this paper.