Electromagnetic theory of diffractive optics

As a result of the continuously improving resolution of the VLSI-based micro-optic fabrication technology, diffractive optical elements can now be manufactured that no longer obey the usual physical optics boundary conditions and the paraxial Fresnel and Fraunhofer diffraction integrals. Rigorous electromagnetic diffraction theory of gratings is applied here to predict the limits of the approximate theory, and to analyze and design diffractive microelements that can be treated only within the framework of the rigorous theory.