Scattering by Spherical and Cylindrical Fluid Acoustic Eaton Lenses

Cylindrical and spherical fluid Eaton lenses have been analyzed by wave optics for the particular case of monochromatic plane incident radiation.

The farfield scattered radiation patterns indicate a nearly even splitting of scattered energy between forward and backscatter corresponding to shadow forming and reflected radiation respectively. The total scattering cross sections for ϱ-c boundary matched Eaton lenses approach, in an oscillatory manner, a value equal to approximately twice the projected area. Thus at high frequencies the Eaton lenses behave as plane mirrors at normal incidence. The cylindrical Eaton lens forms a more or less definite shadow at moderate frequencies while the shadow for the corresponding spherical lens contains a pronounced Fresnel bright spot.