Theoretical analysis of curved Bragg diffraction images from plane wave reference volume holograms.

We analyze the shape of Bragg diffraction images from plane wave reference volume holograms in a 4-f geometry. When the volume hologram is probed by out-of-plane probe beams, the diffraction images become curved lines. Exploiting the k-sphere formulation and Fourier optics analysis, we present both geometrical and analytical solutions of the curved shape, which are distorted ellipses. Parameters and conditions related to the curvature are characterized, and experimental evidence is presented.