Deformation measurement by holographic interferometry. Analysis on curved surfaces. General aspects

Holographic Interferometry is briefly outlined in the case of large deformations. Modifications at the reconstruction are necessary to recover the previously invisible fringes. The spacing and contrast are characterized by the fringe and visibility vectors. The relevant first derivative of the path difference involves the polar decomposition of the deformation gradient and some affine connections. Owing to the modification, one must consider the aberration together with changes of geodesic curvatures and of surface curvatures. This leads to similar aspects for hypersurfaces with remarks concerning the general problem of the gravitational lens. (C) 2001 Elsevier Science Ltd. All rights reserved.