1. Reflection of a portion of the Light incident on a planar Interface between two homogeneous media having different refractive indices. Fresnel reflection occurs at the air-glass interfaces at entrance and exit ends of an optical fiber. Resultant Transmission losses (on the order of 4% per interface) can be virtually eliminated by use of anti-reflection coatings or index matching material. 2. The reflection that occurs at the planar Junction of two materials having different refractive indices. Fresnel reflection is not a function of the angle of incidence.