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Fresnel Reflectivity

Consider light intersecting the plane interface between two materials, numbered 1 and 2, with an incident electric field E_i, a reflected electric field E_r, and a transmitted electric field E_t. The transmission and reflection coefficients are functions of the angle of incidence and the polarization of the incident light. If θ_i is the incident (and reflected) angle and θ_t is the transmitted angle, then the electric field reflection and transmission coefficients are given by the Fresnel formulae.

where n_j = n_j +iκ_j = the complex index of refraction of material _j. Here, ║ represents an electric field vector that lies parallel to the plane defined by the direction of the incident light and a normal to the material interface. Other names for ║ polarization include p polarization and TM (transverse magnetic) polarization. The polarization denoted by ┴ represents an electric field vector that lies in a plane perpendicular to that defined by the direction of the incident light and a normal to the surface. Other names for ┴ polarization include s polarization and TE (transverse electric) polarization. Note that