Abstract: A beam combiner is disclosed that comprises a planar lightwave circuit that is based on undoped silicon nitride-based surface waveguides, wherein the planar lightwave circuit comprises a plurality of input ports, a mixing region, and an output port, and wherein the mixing region comprises a plurality of directional couplers that are arranged in a tree structure. Embodiments of the present invention are capable of combining a plurality of light signals characterized by disparate wavelengths on irregular spacings with low loss. Further, the present invention enables high-volume, low cost production of beam combiners capable of combining three or more light signals into a single composite output beam.

Abstract: A beam combiner is disclosed that comprises a planar lightwave circuit that is based on undoped silicon nitride-based surface waveguides, wherein the planar lightwave circuit comprises a plurality of input ports, a mixing region, and an output port, and wherein the mixing region comprises a plurality of directional couplers that are arranged in a tree structure. Embodiments of the present invention are capable of combining a plurality of light signals characterized by disparate wavelengths on irregular spacings with low loss. Further, the present invention enables high-volume, low cost production of beam combiners capable of combining three or more light signals into a single composite output beam.

Abstract: A beam combiner is disclosed that comprises a planar lightwave circuit that is based on undoped silicon nitride-based surface waveguides, wherein the planar lightwave circuit comprises a plurality of input ports, a mixing region, and an output port, and wherein the mixing region comprises a plurality of directional couplers that are arranged in a tree structure. Embodiments of the present invention are capable of combining a plurality of light signals characterized by disparate wavelengths on irregular spacings with low loss. Further, the present invention enables high-volume, low cost production of beam combiners capable of combining three or more light signals into a single composite output beam.

Abstract: Roughly described, arrayed waveguide grating apparatus includes one or more input and/or output waveguides which are shaped and oriented such that optical energy communicated with the waveguide array is, within a distance of no more than 1 mm into the mouth of the waveguide, directed substantially in-line with the optical centerline of the waveguide. In one embodiment, the waveguides are shaped and oriented such that the optical energy enters or exits the waveguide substantially-line with the optical centerline of each waveguide. In another embodiment the waveguides are shaped and oriented such that optical energy is, at the mouth of each waveguide, directed off-axis, and the waveguide includes mode conversion means such that optical energy is directed substantially in-line with the optical centerline within a distance of no more than 1 mm into the mouth of the waveguide. The mode conversion means may, for example, include a non-adiabatic lateral optical centerline shift.