Electronic shearography applied to static and vibrating objects

An optical shearography configuration is presented which can be used for the measurement of slope change for static and vibrating objects in real time. Displacement and vibration amplitude fields are extracted from the shear data, which is an useful property in noise environments. In a Michelson interferometer set-up the two arms are provided with a phase-shift mirror and a bias modulation mirror to carry out the numerical evaluation of the measured deformation. Experimental results for an edge- clamped aluminium plate are presented. © 1994.