Boundary element method for vector modeling diffractive optical elements

Two boundary integral models of vector diffraction from diffractive optical elements (DOEs) are presented. The first is the method of moments and the second, the boundary element method. The advantages of boundary integral methods over alternate vector diffraction models are threefold. First, only the surface of the diffractive structure is sampled, not the entire solution space. Second, they can model both finite aperiodic and infinite periodic DOEs and, third, once the surface current distribution is determined for a given incident field, it can be used to determine the vector field amplitudes anywhere in space or over any region and/or regions of space. Results are presented for the diffraction of a TM-polarized plane wave from three conducting surfaces; a plate, grating, and diffractive lens.