Abstract

An extinction theorem analysis is applied to calculate diffraction efficiency of multilayer over­coated low-efficiency gratings. The nominal efficiency of the –1 order, for example, may be 1-2%. However, in certain resonance conditions, the efficiency may jump to as much as 50 % with a corresponding reduction in the specular beam. Numerous numerical examples are presented. These include replicating and nonreplicating interface profiles. The nonreplicating examples may be a gradually varying shape from interface to interface or several planar interfaces and the profile at a single interface. The incident beam may be either a plane wave or a Gaussian. The effect of guided wave resonance on the reflected beam is presented.

© 1988 Optical Society of America