Abstract

We are engaged in a research effort to design modulated ribbon gratings that are composed of a number of parallel, dielectric cylinders joined by flat sections of dielectric material. As an important first step in this work, we have solved for the multiply scattered field from a planar array of N parallel dielectric cylinders. The multiple-scattering model takes into account all contributions to the excitation of a particular cylinder by the radiation scattered from the remaining cylinders. A common approach to calculating the field scattered by two or more parallel cylinders is to express the multiple-scattering linear equations in matrix form and then to solve the matrix expression for the multiple scattering coefficients by iterative refinement or matrix inversion. However, when the expansion of the matrix expression is divergent, the iterative refinement method is also divergent. In addition, the matrix inversion approach fails for ill-conditioned matrices.

© 1990 Optical Society of America