An NDT electro-optic system for mosaics investigations

Electronic speckle pattern interferometry (ESPI) is a well-known tool in cultural heritage diagnostics. It is also suitable to reveal cracks and debondings of tiles in ancient mosaics of Roman and Medieval age. This paper describes a portable electro-optic system as a diagnostic tool to evaluate the state of conservation of ancient mosaics. The proposed system is based on the integration of ESPI and local speckle correlation techniques. Some experiments have been carried out on real, ancient, mosaics in laboratory and in situ. The different features of each technique are outlined and a comparison with holographic interferometry is also given. [Copyright &y& Elsevier]