Improvement of the diffraction efficiency of speckle interferograms by selecting a method of manifestation and developer for practical use in experimental mechanics

This article presents a qualitatively new developed technology of out-of-band registration of speckle holograms in the study of deformations in the concentration zone on samples with holes.
Summary. One of the most important aspects of speckle-holographic interferometry is the quality of the resulting speckle-hologram, which largely determines its diffraction efficiency. In this case, the improvement of diffraction efficiency in solving practical problems is carried out through the selection of the developer of photographic plates, the installation of a certain exposure time and the choice of methods for processing photographic plates. However, in practice, there are often problems of obtaining the maximum diffraction efficiency of holograms. We made a choice of developer, exposure time, as well as methods of photo processing of speckle holograms in colliding beams in the process of practical experiment.
Practical significance. The technology of out-of-band registration of speckle holograms described in the article can be used in the process of research of SSS of full-scale aircraft structures in areas of stress concentration, as well as their detection during industrial full-scale tests.