The Role of Evanescent Waves in Three-Dimensional Near Field Imaging

摘要

The structural information carried by the evanescent components of the scattered field is discussed for the case of a single homogeneous plane wave incident on a weakly scattering three-dimensional medium. It is shown that, unlike the homogeneous components of the scattered field, the evanescent components are related to the three-dimensional Fourier transform of the dielectric susceptibility through a generalized Radon trasform. The region of the three-dimensional Fourier space that is accessible from evanescent wave measurements is discussed, as well as the spatial resolution attainable in a typical multiple-view scattering experiment.