Scattering From Cylinders Near a Dielectric Half-Space Using a General Method of Images

The two-dimensional scattering of an arbitrary beam of radiation from multiple dielectric cylinders near a dielectric half-space is considered using a general method of images (GMI). The electromagnetic fields are broken down into cylindrical waves so that the boundary conditions for the cylinders can be applied directly. Two approaches for calculating the multiple scattering between the cylinders and the planar interface are compared: the plane-wave integral method and the Fourier series method. The plane-wave integral method involves numerically integrating a plane-wave spectrum for the reflection from the planar interface. The Fourier series method avoids numerical integration but poses problems for evanescent fields. By introducing evanescent field correction terms we are able to show the equivalence of the two methods.