High-sensitivity holographic interferometry method for studying transparent objects with small transverse size

A new method for studying transparent objects with a small transverse size is considered. The method is based on lateral-shift holographic interferometry combining the displacement of the transparent object under investigation between the recordings of a pair of holographic interference patterns and their optical treatment. The interference patterns of the transparent object under investigation with a lateral shift equal to or larger than the linear size of the object are equivalent to the interference patterns obtained in a double-beam interferometer with a reference wave. In addition, such patterns are characterized by a higher sensitivity of imaging of optical inhomogeneities of the object under investigation. The results of experiments on testing this method for monitoring optical inhomogeneities of the active medium crystal of a solid-state laser are reported. The resultant interference patterns depict optical inhomogeneity of the crystal with a sensitivity 12 times higher.