An understanding of correlation singularities is fundamentally important in imaging science. Until now spatial coherence studies have examined a two-dimensional projection of the four-dimensional correlation function, finding so-called correlation vortices or correlation ring dislocations in a given transverse plane. Here we describe the properties and symmetries of the full four-dimensional correlation function. The general solution is found to be a hyperbola in two reduced dimensions. For perfect coherence this reduces to crossed straight lines, whereas in the incoherent limit it reduces to parallel lines. These results elucidate a number of previous experimental and theoretical observations regarding correlation singularities and suggest other behaviors of such singularities.

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Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

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Department, Program, or Center

Chester F. Carlson Center for Imaging Science (COS)


RIT – Main Campus