Speckle and speckle-shearing interferometers combined for the stimultaneous determination of out-of-plane displacement and slope

Abstract

Speckle and speckle-shearing interferometer geometries have been combined into a single setup by the use of a small ground glass reference diffuser on the lens pupil. Sheared fields are obtained with a split lens arrangement. Judicious aperturing results in separated diffraction halos at the FT plane. Fringe patterns corresponding to out-of-plane displacement and slope are obtained by filtering via the appropriate halos. A four-aperture arrangement coupled with shearing elements extends the method to obtain the moiré curvature pattern.