The one-step phase-shifting technique for wave-front interferometry

Abstract

Hitherto, phase-shifting schemes in wave-front interferometry required a minimum of two precise phase steps in order to derive the phase. This paper outlines and demonstrates a novel technique entailing one precise phase step. Numerical analyses of phase-drift errors indicate that the proposed technique compares favourably with performances of the three- and four-bucket algorithms currently in use. Furthermore, it minimizes the period of computation by necessitating the use of three processing frames.