ELECTRONIC SPECKLE CONTOURING

Electronic speckle contouring is concerned with shape measurement by using fringe-projection techniques in electronic speckle pattern interferometry (ESPI). Conventional in-plane and out-of-plane displacement-sensitive ESPI instrumentation may be used for contouring without any alterations to the optical hardware. The contour maps of three-dimensional diffuse objects are obtained by small shifts of optical fibers carrying the object-illumination and reference beams. It is theoretically demonstrated and experimentally verified that the fringe patterns produced are identical to projected fringe contours and may be analyzed in the usual way. Phase measurement and digital image processing are used for data reduction.