Correction of wavefront reconstruction errors caused by light source intensity instability in phase-shifting interferometry

Abstract

In the recording process of phase-shifting interferometry, intensity fluctuation caused by light source instability may occur and then introduce amplitude and phase errors to the reconstructed object wavefront. A simple direct algorithm of digital data processing to correct these errors is proposed and satisfactorily verified by both computer simulations and optical experiments. This method can work without specific knowledge of the source intensity fluctuation, and it reduces both the amplitude and phase errors of the reconstructed wavefront by about two orders of magnitude in computer simulations.