Electronic speckle pattern interferometry system for in situ deformation monitoring on buildings

Abstract

An electronic speckle pattern interferometry system has been developed for in situ measurements of microdeformations on buildings or monuments. Design of the optomechanical setup received special attention to allow firm and steady contact between object and optical head. Features are the miniaturization of the light source (laser diode) and pickup (CCD camera). Image processing was carried out with a personal computer. Deformation monitoring was demonstrated successfully over periods of several weeks in the study of decay mechanisms of walls in an historic church.