Moire and spatial-carrier approaches to phase-shifting interferometry

Modified wavefront analysis concepts for interferometric optical testing are presented, specifically: a moire fringes version of the temporal phase-shifting method and spatial-carrier phase-shifting. These techniques require working with a finite fringe observation field in the interferometer; therefore, additional analysis of the imaging optics is necessary. The influence of the interferometer construction and the chosen method of analysis upon the measurement error is discussed. Extended experimental and theoretical comparison of the techniques presented is given in order to fulfill a wide range of user requirements.