Lossy Multistep Lamellar Gratings in Conical Diffraction Mountings: An Exact Eigenfunction Solution

Abstract

The method of exact eigenfunctions has proven to be effective for the scalar grating problem. This makes it worthwhile to apply the method to the vectorial grating problem, also referred to as the problem of conical diffraction. The approach to exact eigenfunctions considered here relies on a refinement of approximate eigenvalues. For complicated gratings in particular, this technique reduces the numerical effort required to compute the vectorial eigenfunctions. Metallic and dielectric cavity-type structures as well as other structures with strong resonances are studied. Good convergence properties have been observed for a wide range of parameter values. The vectorial treatment of the case of general incidence provides new theoretical results for the color-separation problem.