Holographic microscopic interferometry with respect to the estimation of stress and strain in micro-opto-electro-mechanical systems (MOEMS)

摘要

Abstract: Holographic microscopy with conjugate reconstruction for the interferometric determination of three-dimensional displacement was used for the investigation of the mechanical behavior of micromechanic and microelectronic components. An experimental set-up for the exposure of the holographic interferograms was used for the application of the spatial heterodyne technique, for the application of phase shifting, and for electro-optic holography. Three holograms for different illumination directions recorded on one holographic plate are reconstructed conjugately, and spatial heterodyne technique a well as phase shift technique were used to evaluate the interferograms. Only by conjugated reconstruction it is possible to obtain a perfectly optimized interferometer for the static evaluation method. The evaluation of interferograms which are strongly disturbed by speckle noise can be performed successfully. A comparison of the results of the application of both techniques is given. The influence of the speckle effect on the resolution was investigated. !16