Small perturbation analysis of oblique incidence in dielectric gratings

Abstract

In this paper, the method of first-order perturbation is proposed to investigate the plane-wane scattering by dielectric gratings with a small modulation index at oblique incidence. Under the assumption of small perturbation, the cross coupling between the fields of the polarizations (TE and TM) due to the oblique incidence cart be represented by the TE and TM transmission lines fed by distributed current and (or) voltage sources, respectively. The results show good agreement with that obtained by a rigorous formulation. (C) 1998 John Wiley & Sons, Inc.