title: Spiral interferogram analysis.
abstract: Interference microscopy using spatial Fourier filtering with a vortex phase element leads to interference fringes that are spirals rather than closed rings. Depressions and elevations in the optical thickness of the sample can be distinguished immediately by the sense of rotation of the spirals. This property allows an unambiguous reconstruction of the object's phase profile from one single interferogram. We investigate the theoretical background of "spiral interferometry" and suggest various demodulation techniques based on the processing of one single interferogram or multiple interferograms.
authors.affiliation: Division for Biomedical Physics, Innsbruck Medical University, Austria.
authors.forename: Alexander
authors.initials: A
authors.lastname: Jesacher
authors.forename: Severin
authors.initials: S
authors.lastname: Fürhapter
authors.forename: Stefan
authors.initials: S
authors.lastname: Bernet
authors.forename: Monika
authors.initials: M
authors.lastname: Ritsch-Marte