Theory of wavefront reversal of radiation having a spatially inhomogeneous average intensity distribution

A spectral method is used in an attempt to find a unified approach to describe several variants of wavefront reversal in stimulated scattering: in a waveguide and when spatially inhomogeneous and single-mode radiation is focused by a lens. It is found that this involves allowing for a specific correlation between the spatial spectral components in the expansion of the pump field. Approximate solutions are found for the scattered field in these cases.