Generalized source method: New possibilities for waveguide and grating problems

A new, general and exact method for resolving waveguide and grating problems is presented whereby the unknown electric field in a given dielectric distribution in the presence of an arbitrary source distribution can br obtained exactly from the known complete electric field solution in a simpler dielectric structure in thc presence of the same source distribution. Thr method can be used in the form of an iterative scheme. The solution can also be obtained through an implicit equation which can bu solved numerically without convergence problem by matrix inversion. The application of the method to the case of abnormal reflection under normal incidence from a segmented waveguide is given as an example.