The coupled-wave method formulated by Moharam and Gaylord [J. Opt. Soc. Am. <b>73</b>, 451 (1983)] is known to be slowly converging, especially for TM polarization of metallic lamellar gratings. The slow convergence rate has been analyzed in detail by Li and Haggans [J. Opt. Soc. Am. A <b>10</b>, 1184 (1993)], who made clear that special care must be taken when coupled-wave methods are used for TM polarization. By reformulating the eigenproblem of the coupled-wave method, we provide numerical evidence and argue that highly improved convergence rates similar to the TE polarization case can be obtained. The discussion includes both nonconical and conical mountings.
© 1996 Optical Society of America
Philippe Lalanne and G. Michael Morris, "Highly improved convergence of the coupled-wave method for TM polarization," J. Opt. Soc. Am. A 13, 779-784 (1996)