Phase-shifting profilometer resolution limit estimation via modulation transfer function analysis

Abstract

This study aims to find both lateral and depth resolution limit of a phase-shifting profilometry (PSP) system by investigating the effect of its modulation transfer function (MTF) as a function of the sinusoidal fringe frequency on the resolution of its output image. Upon finding the resolution limit via MTF analysis, the result is verified experimentally through the 3D reconstruction of a test object with known dimensions. This allows deeper insight on how the combination of system parameters and MTF affect the overall depth and lateral resolution of a phase-shifting profilometer. This also gives the user a prior knowledge of which optical component/s should be used for a desired application.