Wavefront-shearing interferometer in an adaptive system with optical feedback

An adaptive optical system designed for the compensation of small-scale phase distortions, containing a liquid-crystal phase modulator and an optical feedback ring, was investigated. A new method was employed for the visualisation of the phase with the aid of a wedge-shaped wavefront-shearing interferometer incorporating a holographic filter. The stability of the system and the conditions governing the compensation of phase distortions were studied analytically. The suppression of small-scale phase distortions was observed experimentally.