Adaptive Optics Systems with Liquid-Crystal Phase-Shift Interferometers

摘要

An adaptive optics system has been developed to real-time correct optical aberrations due to external disturbances. In wavefront sensing, a novel wavefront sensing system based on liquid-crystal phase-shift interferometry is proposed to precisely and fast detect optical wavefront variation with the helps of precise phase correction and transient nematic driving methods. A home-made digital signal processing controller using the feedback wavefront information from the phase-shift interferometry wavefront sensor drives deformable mirrors to reduce optical aberrations successfully. The developed multichannel adaptive optics system has the dynamic bandwidth of control loop up to 30 Hz. The experimental results to compensate several hertz thermal turbulence demonstrate that the steady state error of the wavefront phase was under 0.02 π rms and the signal-to-noise ratio improvement is better than 20 dB. Also, the Strehl ratio of the focusing spot can be increased from 0.5 to 0.9.