Holographic contouring method: application to automatic measurements of surface deffects in artwork

An electro-optical system for the detection and quantitative measurements of surface or subsurface defects is presented; it is based on a holographic contouring technique and digital image processing for an automatic analysis of fringe patterns. Several approaches have been followed on models, so that the defects can be unambiguously detected and possibly quantitatively analyzed. Some examples of applications in deterioration investigations of ancient artworks are reported.