Automatic control of laser beams aberrations in air using an Adaptive Optics system prototype based on interferometrictechniques

摘要

In this paper we present a prototype of an Adaptive Optics system for the control of geometrical fluctuations in a laser beam in air based on the interferometric detection of the beam phase front. We show that this technique is of particular interest when high sensitivity and high band-pass are required for correction of small perturbations. The main technique adopted for the control is based on the interferometric detection of phase-front fluctuations: the beam is made to interfere with a reference beam, properly obtained, and the phase difference is read by means of a pixellated photodiode. The signals are then sampled by a fast automatic control system, which computes also the correction signals, and sent to the deformable mirror. In the paper we show and discuss some experimental results of the technique, discussing the most important limits and estimating the possibility of future developments and improvements.