Phase-shifting interferometry based on dynamic mode decomposition

A phase retrieval algorithm in phase-shifting interferometry is presented based on dynamic mode decomposition (DMD). The complex-valued spatial mode obtained from the DMD of phase-shifted interferograms allows the derivation of the phase estimate. At the same time, the oscillation frequency associated with the spatial mode provides the phase step estimate. The performance of the proposed method is compared to methods based on least squares and principle component analysis. The simulation and experimental results demonstrate the improvement in the phase estimation accuracy and noise robustness offered by the proposed method and thus substantiate its practical applicability.