ABSTRACT
This chapter introducses basics of the “fringe analysis”, which is one of the major methods for digitizing various physical phenomena. It investigates the principles and basic procedures and some of their applications in the fringe analysis with a computer. The chapter describes a distinctive process of converting a wrapped phase map to the final physical distribution, namely, “phase unwrapping”. In the early period of the computer’s introduction, an image processing technique for contour-like fringes, including extractions of the fringe centers and their order number evaluations, was mainstream in the fringe analysis where the sub-fringe order was estimated through the interpolation between fringe centers. More sophisticated analysis principles were evolved after the 1970s; they are, namely, the sub-fringe phase analysis represented by the fringe scanning method, the phase-shifting method, and the Fourier transformation method. The chapter show an actual process of the fringe analysis for profilometry using the deformed grating method with an interference fringe projection.
