Image theory for the general isotropic ideal boundary

The ideal boundary (IB) concept was recently generalized from that of perfect electric and magnetic conducting boundaries to describe the most general isotropic surface at which the complex Poynting vector has no normal component. The ensuing boundary operator is not linear in general, but one which can be labeled as semilinear. Previously given plane-wave theory is generalized in this paper to finding the reflected waves for arbitrary electromagnetic fields incident to a planar IB surface. The source of the reflected field is interpreted as the image of the source of the original field, and its analytic expressions are given. The theory is applied to a dipole in complex space, corresponding to a Gaussian beam incident onto the IB surface. (C) 2000 John Wiley & Sons, Inc.