Wavefront sensor using the Talbot effect

A method for measuring optical wavefronts is proposed by properly sampling the light amplitude distribution with a two-dimensional periodic mask. At t he Talbot planes, where a reference wavefront (spherical or plane) would or iginate replicas of the aperture, distortions of the resulting selfimages t ake place. These intensity patterns are detected and processed for obtainin g the required wavefront information. The approach is illustrated with some experimental results. (C) 1999 Elsevier Science Ltd. All rights reserved.