Advanced iterative algorithm for phase extraction of randomly phase-shifted interferograms

TLDR

An advanced random phase‑shifting algorithm is proposed to extract phase distributions from randomly phase‑shifted interferograms. The algorithm employs a least‑squares iterative procedure that separates frame‑to‑frame from pixel‑to‑pixel updates, and its validity was demonstrated by computer simulation. It achieves stable, accurate phase extraction from as few as three randomly shifted interferograms, and it is simple, fast, and fully automatic.

Abstract

An advanced random phase-shifting algorithm to extract phase distributions from randomly phase-shifted interferograms is proposed. The algorithm is based on a least-squares iterative procedure, but it copes with the limitation of the existing iterative algorithms by separating a frame-to-frame iteration from a pixel-to-pixel iteration. The algorithm provides stable convergence and accurate phase extraction with as few as three interferograms, even when the phase shifts are completely random. The algorithm is simple, fast, and fully automatic. A computer simulation is conducted to prove the concept.