Laser-controlled adaptive optics for beam quality improvements in a multi-pass thin-disk amplifier

Abstract

We devise a laser-controlled adaptive optical element that operates intracavity under high-intensity radiation. This element substitutes a conventional mechanically deformable mirror and is free of critical heat-sensitive components and electronics. The deformation mechanism is based on the projection of a continuous-wave control laser onto a specially designed mirror. Mounted to a water-cooled heat sink, the mirror can handle laser radiation beyond 3 MW/cm. The properties of the adaptive optical element, including the maximum correctable wavefront pitch of 800 nm, are discussed. The successful implementation in a multi-pass thin-disk amplifier is presented. An improvement of the beam quality by a factor of three is achieved. We identify measures to enhance the performance of the adaptive optics towards efficient operation in a high-power laser system.

Evaluating the Potential of Laser Beam Quality Improvement by Adaptive Optics System

“…Beam quality of the light exiting from lasers is usually quite poor in high-energy lasers) because of multimode oscillation, thermal effect, phase perturbation, and so on [1][2][3][4]. Nowadays, AO (adaptive optics) systems have been extensively used to improve the beam quality in high-energy lasers [5][6][7][8][9]. By compensating the phase aberration, AO systems could make the far-field intensity distribution very close to the ideal.…”