Abstract: A device to monitor light output from a light source, including a V-groove substrate with a reflective coating deposited on at least one surface, an optical fiber, a light source positioned so that an amount of the light emitted, which is less than 100%, enters the optical fiber, a light intensity or source detector positioned so that at least some of the light emitted from the light source, that did not enter the optical fiber impinges upon the light intensity detector, and feedback circuitry. A method of producing a device including the steps of coating a surface of a V-groove substrate with a reflective material, placing a light source in said V-groove substrate.

Abstract: A waveguide optical amplifier include a substrate and a guiding or active layer. The substrate has a substrate surface and a substrate index of refraction. The guiding layer is of Zirconium dioxide (ZrO.sub.2) and/or Alumina (Al.sub.2 O.sub.3) and is carried on a cladding layer over the substrate surface. The guiding layer has a guiding layer index of refraction which is higher than the cladding index of refraction. The Zirconium dioxide guiding layer is doped with rare earth materials.