Contribution of wave aberrations represented by Zernike polynomials to the cross-correlation function between distorted and actual speckle patterns

Abstract

Speckles are sensitive to the slightest inhomogeneities of the medium, which is used in optical research methods such as speckle interferometry. However, the stochastic nature of propagation of speckle fields complicates their accurate detection and processing. For example, aberrations in the optical system result in the decorrelation of the image of speckles with the actual speckles that are observed in free space. The report will consider the main types of wave aberrations of optical system and their influence on the correlation properties of speckle patterns. The research results can be used to optimize optical systems in which speckles play a significant role, for example, in classical ghost imaging.

Damage Security Intelligent Identification of Wharf Concrete Structures under Deep Learning and Digital Image Technology

“…The DIC method calculates the similarity of the two sub-regions before and after deformation using the gray gradient value of the speckle image to get an accurate deformation parameter estimation. Commonly used criteria can be divided into cross-correlation and variance synthesis criteria according to the algorithm [24].…”