Hidden rays for H-polarized diffraction by a composite wedge

One of canonical structures, of which exact solution is not available until now, is a composite wedge consisting of perfect conductor and lossless dielectric. Recently the hidden ray of diffraction (HRD) has been developed to provide approximate but highly-accurate analytical solution to the diffraction by a composite wedge illuminated by an E-polarized plane wave. In this paper, the method of hidden rays is applied to the case that an H-polarized unit plane wave u_i(rho,thetas) with arbitrary angle thetas_i is incident on a composite wedge. As shown in Fig.1, the composite wedge consists of perfect conductor in S_c and lossless dielectric of relative dielectric constant epsiv in S_d. The air region S₀ consists of two boundaries at thetas = thetas_d and thetas_c which satisfy pi < thetas_c -thetas_d < 2pi.