Arrangement for displaying deformations of deformable structures by holographic interferometry

摘要

The arrangement for displaying deformations of deformable structures by holographic interferometry, in which the interferogramme of the object is obtained by double exposure for an object subjected to periodic deformation or by prolonged exposure by comparison with the period of vibration for a vibrating object, comprises a recording electro- optical, photoconductive crystal to which is applied an electrical field substantially orthogonal to the mean direction of the fringes. The interferogramme is viewed in an image plane or recorded in a memory tube where it is desired to memorize the information because readout destroys the information. The arrangement can be made compact by integration of the displaying means in an enclosure. In that case, the source furnishes a reference beam and an object beam which are respectively directed towards the enclosure and the object by optic cables.