A field picture of wave propagation in inhomogeneous dielectric lenses

This article presents the radiation and scattering patterns, and the interior field distributions, of three inhomogeneous dielectric lenses: the Luneburg (1944), Maxwell fish-eye (1860), and Eaton-Lippmann (1952) lenses. The purpose is to provide a picture of wave propagation through these lenses. A better understanding of the field picture, especially the nature of the focal points, is helpful to the practical design of the lenses.