Some considerations of reduction of reference phase error in phase-stepping interferometry

Positioning errors and miscalibrations of the phase-stepping device in a ph ase-stepping interferometer lead to systematic errors proportional to twice the measured phase distribution. We discuss the historical development of various error-compensating phase-shift algorithms from a unified mathematic al point of view. Furthermore, we demonstrate experimentally that systemati c errors can also be removed a posteriori. A Twyman-Green-type microlens te st interferometer was used for the experiments. (C) 1999 Optical Society of America OCIS codes: 050.5080, 120.3180, 120.5050, 220.4840.