Numerical processing of speckle photography data by Fourier transform.
Using a 1-D analysis of a double-exposed specklegram, we explore the influence of the diffraction halo removal in the numerical processing of data when it is done via discrete Fourier transform. Relative errors in displacements appear if the removal is not done, and they increase as fringe visibility and fringe density decrease. These errors are <0.5% for fringe densities larger than six fringes within the diffraction halo.
Kaufmann
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