Fundamentals of laser hologram interferometry and speckle metrology are reviewed with special emphasis on principles governing formation of fringe patterns and dependence of this phenomenon on object's motion and/or deformation. Processes relating to recording and reconstruction of holograms and specklegrams are discussed and are followed by presentation of procedures for their quantitative interpretation based on the method of projection matrices. Since there is a unique projection matrix for each hologram, or specklegram recorded from a different direction, each of the matrix equations relates the fringe parameters and recording geometry to the unknown deformation. Therefore, the resulting system of matrix equations can be solved for the unknown displacements, rotations, and strains.
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