A PHASE UNWRAPPING TECHNIQUE FOR OBJECT RELIEF DETERMINATION

Phase shifting methods are widely used in photomechanics to analyse fr inge patterns obtained from interferometry, moire, etc. The phase is d etermined by modulo 2pi and an unwrapping process is needed. An algori thm is presented which avoids most of the inconsistency of the phase f ield. It can be applied to the relief determination of virtually any o bject shape. In this paper, two applications are performed using the p rojection of a parallel line grating with a pitch equal to 4mm. The ac curacy is shown to be around 0.1 mm.