Light scattering from dielectric targets composed of a continuous assembly of circular disks

Abstract

A technique for computing the electromagnetic fields scattered by spheres, cylinders, spheroids, spirals, toroids, and other targets which can be subdivided into circular disks is given. First-order calculations are performed for targets the size and refractive index of which preclude the creation of standing waves within the target. It is found that the scattering signatures of these various shapes are distinguishable for wavelengths larger than the target, but the differences rapidly diminish, as expected, with increasing wavelength. Finite cylinders are compared to prolate spheroids of equal volume, toroids are compared with oblate spheroids of equal volume, and calculations of the CIDS ratio for a spiral target are made for various wavelengths. It is found, on comparing these spiral calculations to other work on essentially 1-D spirals, that giving the spiral wire even a very small radius significantly affects the CIDS pattern for backscattering.