Brewster angle: tan(theta_B) = n_2/n_1; r_p(theta_B) = 0 by IVT

Brewster's-angle framework (Brewster 1815 Phil Trans R Soc). Setup: at the dielectric interface with indices n_1, n_2, the p-polarised Fresnel coefficient r_p = (n_2 cos theta_i - n_1 cos theta_t)/(n_2 cos theta_i + n_1 cos theta_t). At…