Single frame interferogram evaluation

Abstract

We present a simple and novel algorithm for the phase extraction from a single interferogram based on the spatial processing of interference patterns. This new evaluation procedure is suitable for application in environments where the presence of vibrations impedes the use of a classical phase-shifting interferometry scheme with multiple exposures. The algorithm does not require the introduction of a linear carrier as required in Fourier transform techniques. The addition of a carrier can be a significant drawback, e.g. in the case of wavefronts with strong aberrations where the minimum required linear carrier is not even resolved by the detector. The basic idea relies on the spatial application of a temporal phase-shifting algorithm and an iterative correction process to obtain an accurate reconstruction of the wavefront. The validity and performance of the proposed method is shown with numerical and experimental results.