Scattering from arbitrarily oriented dielectric disks in the physical optics regime

Abstract

A solution has been developed for electromagnetic-wave scattering from a dielectric disk of arbitrary shape and orientation. The solution is obtained by approximating the fields inside the disk with the fields induced inside an identically oriented dielectric slab having the same thickness and dielectric constant. The fields inside the disk excite conduction and polarization currents, which are in turn used to calculate the fields scattered from the disk. This computation has been executed for observers in the far field of the disk for arbitrarily polarized incident waves, and the solution has been expressed in the form of a dyadic scattering amplitude. The results apply when the minimum dimension of the disk’s cross section is large compared with both wavelength and disk thickness, although the thickness need not be small compared with wavelength. Examples of the dependence of the scattering amplitude on frequency, relative dielectric constant, and disk orientation are presented for disks of circular cross section.