Cladding in optical fibers is one or more layers of materials of lower refractive index, in intimate contact with a core material of higher refractive index. The cladding causes light to be confined to the core of the fiber by total internal reflection at the boundary between the two. Light propagation in the cladding is suppressed in typical fiber. Improving transmission through fibers by applying a cladding was discovered in 1953 by Dutch scientist . Some fibers can support cladding modes in which light propagates in the cladding as well as the core.