Experimental researches of speckle interferometry method of lateral micro-displacements of a scattering object with digital processing of registered speckle-modulated interference images
The processes of measuring signal formation using the method of laser speckle interferometry of lateral micro-displacement of the scattering rough surface of technical objects are experimentally researched. The possibilities of numerical processing of speckle-modulated interference images recorded in the experiment are investigated. In the work, speckle-modulated interference images were recorded at the output of the speckle interferometer after a certain time interval. On the matrices with the registered images, a local area was allocated in which the total intensity was calculated. The relative intensity distribution was determined during heating to the maximum temperature. The lateral micro-displacement of the scattering rough surface increased to the maximum value, then the displacement stopped at the maximum value. Then the glow voltage was switched off and the reverse process of shifting the scattering surface to its original position began. Experimental oscillograms of the lateral displacement of the scattering surface of a technical object due to its heating and cooling are obtained. The studies were carried out at different locations of the selected area on the original recorded images. These studies have shown the repeatability of qualitative and quantitative results in the experiment. The oscillograms were recorded in the far diffraction region with Gaussian illuminating beams. The results of experimental studies are in good agreement with the results of numerical modeling of the complex amplitudes of wave fields at the output of the speckle interferometer and confirm the correctness of the mathematical model of the speckle interferometer of lateral micro-displacements based on diffraction transformations of wave fields.
Lyudmila Aleksandrovna Maksimova
IPTMU RAS - Separate structural subdivision of FRC "Saratov Scientific Center of the Russian Academy of Sciences"
File with report