Laser beam shaping based on wavefront sensorless adaptive optics with stochastic parallel gradient descent algorithm

Abstract

A wavefront sensorless adaptive optics system with a 61-element unimorph deformable mirror is proposed for laser beam shaping. The actuator voltages of the DM are adaptively adjusted with the help of the stochastic parallel gradient descent (SPGD) algorithm. The difference of the target beam and the actual beam recorded by a CCD camera is used as feedback. The experimental results show that this method not only realizes the aberrations correction of the optical system, but also generates annular beam, ratio line focus beam and square beam which agree with the desired targets.