US Patent 10393957 Glued optical fiber bundle

An optical fiber light emitting diode assembly is disclosed. The assembly includes an array of optical fibers that converge to a bundled portion at each end, each optical fiber having a core surrounded by a transparent cladding material with a lower index of refraction than the core. A first adhesive binds the optical fibers in the bundled portion at each end, an end of the first adhesive being adjacent to the end of the optical fibers. A second adhesive, having a different refractive index than the first adhesive, is applied to the end of the optical fibers and the end of the first adhesive. An end part is mounted to the second adhesive. A light emitting diode applies light into the end part through an air gap.