Far-field image of Veselago lens

Abstract

It is shown that perfect imaging of a point source both in near- and far-field regions contradicts electrodynamics although ``superlensing'' is impossible only in the far-field region. These general statements are illustrated by detailed study of evanescent wave propagation in a photonic crystal that is known to be a left-handed medium. An analytical expression for the intensity distribution near the far-field focus is obtained. This distribution contains some novel features and establishes a new ``diffraction limit'' for flat lenses. It is generalized for multiple sources located at different points. The distribution is in very good agreement with computer simulation.