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.