Mapping of microstructural surface changes by phase-shifting electronicspeckle pattern interferometry,

摘要

Abstract: nic speckle pattern interferometry is elaborated in such a way that also spatially resolved image decorrelation can be measured. While retaining the typical ESPI setup for deformation measurements, a speckle correlation formalism is implemented based on the phase-shift method. In many practical situations decorrelation is directly related to surface microstructure changes of a test specimen. Feasibility and restrictions of the method are illustrated by measurements of water-induced changes at the surfaces of natural stones and by monitoring microbiological activity on stones.!6