Optical surface measurement using accurate carrier estimation in Fourier transform fringe analysis and phase unwrapping based upon transport of intensity equation

Interferometry is the most widely used technique for optical surface measurements. In this paper, we present a fast method for recovering phase information from an interferogram. A fast algorithm is developed for fringe analysis, which is based on Fourier transform method and transport of intensity equation. First, we apply Fourier transform method with accurate carrier removal technique to retrieve wrapped phase from an interferogram and then phase unwrapping is carried out using transport of intensity equation. The simulations and experimental results suggest that our interferogram evaluation method is fast and accurate, which is very useful for the phase evaluation problems in interferometry and holography.