Identification and Removal of Phase Errors in Interferometry

Abstract
Using the concept of the complex zeros of the Michelson interferogram (introduced recently) it is shown how phase errors can be identified in measured interferograms. In those cases in which the measured intensity is more accurate than the measured phase (it is shown how to process the measured data to determine this) it is shown how to compute an improved phase from the measured intensity, using the measured phase merely to resolve ambiguities. Computational procedures are described in detail and are illustrated with examples involving measured interferograms (of Taurus A and radio source PO349-27) and ideal data.