Analysis of stress measurement by means of a speckle decorrelation

The paper analyzes stress measurement by means of the method so-called speckle pattern decorrelation. This relatively new and easy realizable method for the non-contact measurement of the small deformation tensor components of an elementary area of the object surface using the statistical properties of speckle field was firstly studied by I. Yamaguchi and later by the authors of this paper, too. At first, the general description of the presented method is briefly referred and the fundamental equations are mentioned both for the case of optically free space and image field. Then some possible experimental arrangements for the measurement of the deformation component epsilon(xx) (specific elongation) on an investigated object rough surface are designed and analyzed from the point of view sensitivity and range of measurement. Finally, some achieved experimental results are also noticed.