Abstract: A folded optical waveguide structure comprises a substrate supporting a waveguide slab. An array of laterally spaced grating waveguides extends from the slab along the substrate to propagate optical signals to and from a reflective surface of a mirror member at an end face of the substrate. A layer of index matching material is located between the ends of the waveguides and the reflective surface. A thermally conductive, e.g. copper, body is interposed between the mirror member and the substrate such that dimensional changes of the thermally conductive body resulting from changes in ambient temperature of the grating array waveguides, tilt the mirror member against the substrate, away from or toward the end face of the substrate.

Abstract: Methods of fabricating solid state optical waveguide structures comprising a doped silicon dioxide core layer sandwiched between lower and upper doped silicon dioxide cladding layers on a silicon substrate. The core and upper cladding layers are deposited using a plasma enhanced CVD process. The core layer is patterned to define one or more waveguide cores. The lower cladding layer is preferably also deposited using a plasma enhanced CVD process but alternatively may be formed by thermal oxidation.

Abstract: An optical waveguide mode transformer has a substrate supporting a high refractive index core layer surrounded by lower refractive index cladding. The core layer includes a wide input waveguide section to accept a multimode, including a fundamental mode, light input. The input waveguide section is coupled to a narrow output waveguide section by a tapered region having a taper length enabling adiabatic transfer of the fundamental mode of the multimode light from the wide input waveguide section to the output waveguide section while suppressing(stripping) other modes of the multimode light input. The narrow output waveguide section supports a single mode light output comprising said fundamental mode. The core layer is contoured to include a localized upstanding ridge intermediate opposite lateral sides of the core layer.

Abstract: An optical waveguide structure comprising an annealed phosphorous doped silicon dioxide core surrounded by silicon dioxide cladding layers on a silicon substrate. The refractive index of the core exceeds the refractive index of the cladding to enable waveguiding of optical signals in the core. The upper cladding layer, and in one embodiment also the lower cladding, comprises high boron and phosphorous doped silicon dioxide, suitably doped with greater than about 9% of boron and with about 2.5% to 3.5% phosphorous to obtain a thermal coefficient of expansion approximating that of the silicon substrate. In an alternative embodiment, the lower cladding layer comprises thermally grown silicon dioxide, preferably including an upstanding pedestal on which the waveguide core extends.

Abstract: An optical waveguide device comprising a free space region, suitably provided by a slab waveguide, having optical signal ports for coupling to input and output waveguide sections and an optical waveguide grating including an array of grating waveguides coupling the free space region to a reflector surface to provide a folded structure. Dielectric waveguide structures are preferred. The grating includes tapered optical waveguide sections laterally spaced and optically isolated from each other which extend from the free space region, with the grating waveguides continuing as extensions of the tapered waveguide sections. Each of the grating waveguides differs in length from a neighboring grating waveguide by a constant increment, preferably an optical path length increment.

Abstract: An optical waveguide device comprising a free space region, suitably provided by a slab waveguide, having optical signal ports for coupling to input and output waveguide sections and an optical waveguide grating including an array of grating waveguides coupling the free space region to a reflector surface to provide a folded structure. Dielectric waveguide structures are preferred. The grating includes tapered optical waveguide sections laterally spaced and optically isolated from each other which extend from the free space region, with the grating waveguides continuing as extensions of the tapered waveguide sections. Each of the grating waveguides differs in length from a neighboring grating waveguide by a constant increment, preferably an optical path length increment.

Abstract: An optical waveguide device comprising a free space region, suitably provided by a slab waveguide, having optical signal ports for coupling to input and output waveguide sections and an optical waveguide grating including an array of grating waveguides coupling the free space region to a reflector surface to provide a folded structure. Dielectric waveguide structures are preferred. The grating includes tapered optical waveguide sections laterally spaced and optically isolated from each other which extend from the free space region, with the grating waveguides continuing as extensions of the tapered waveguide sections. Each of the grating waveguides differs in length from a neighboring grating waveguide by a constant increment, preferably an optical path length increment.