Abstract: A 1×2 splitter design having low loss is described. The splitter has a non-adiabatic tapered waveguide (22) connected between a substantially single-mode input waveguide (20) and two output waveguides (24, 26). The non-adiabatic tapered waveguide widens in width towards the output waveguide, and merges substantially continuously with the input waveguide in a direction parallel to the optical axis of the input waveguide. This keeps radiation mode generation to a minimum which, in turn, keeps insertion loss low. In the described embodiment, the non-adiabatic taper shape is based on a perturbed cosine function. The 1×2 splitter can be cascaded with other such splitters in order to build a 1×2N splitter design.

Abstract: An arrayed waveguide grating (AWG) device comprising a substrate having a first array of waveguides optically coupled between first and second slab couplers and a second array of input-output waveguides optically coupled at first ends thereof to an input/output side of the second slab-coupler. The input/output waveguide are tapered at first end portions thereof so as to increase in width towards the second slap coupler, and the width (W) of the first ends of the input/output waveguides varies across the second array in a manner so as to increase uniformity of at least on performance parameter, for example adjacent crosstalk (AXT). In the described embodiment, the width (W) of the tapered waveguide ends increases from one side to the array of input/output waveguides to the other, so as to keep the separation(s) between the input/output waveguides.

Abstract: An optical power monitor comprises: an array waveguide grating comprising first and second optical interaction regions between which an input optical signal propagates from a first position on a first side of the first optical interaction region to a second position on a second side of the second optical interaction region, a correspondence between said first and second positions depending upon a wavelength of the optical signal, there being a plurality of array waveguides coupled between a second side of the first optical interaction region and a first side of the second optical interaction region, and a plurality of output waveguides coupled at one end to the second side of the second optical interaction region for outputting different wavelength channel outputs from the second optical interaction region; and detector for detecting said different wavelength channel outputs at the other ends of the output waveguides: wherein the plurality of output waveguides includes at least two output waveguides for at le

Abstract: An arrayed waveguide grating (AWG) device (1) comprising a substrate having a first array of waveguides (8) optically coupled between first and second slab couplers (3, 4) and a second array of input-output waveguides (10) optically coupled at first ends thereof to an input/output side (5) of the second slab-coupler (4). The input/output waveguide are tapered at first end portions (13) thereof so as to increase in width towards the second slap coupler, and the width (W) of the first ends of the input/output waveguides varies across the second array (10) in a manner so as to increase uniformity of at least on performance parameter, for example adjacent crosstalk (AXT). In the described embodiment, the width (W) of the tapered waveguide ends increases from one side to the array of input/output waveguides (10) to the other, so as to keep the separation (s) between the input/output waveguides.

Abstract: An arrayed waveguide grating (AWG) device comprising a substrate having a first array of waveguides optically coupled between first and second slab couplers and a second array of input-output waveguides optically coupled at first ends thereof to an input/output side of the second slab-coupler. The input/output waveguide are tapered at first end portions thereof so as to increase in width towards the second slap coupler, and the width (W) of the first ends of the input/output waveguides varies across the second array in a manner so as to increase uniformity of at least on performance parameter, for example adjacent crosstalk (AXT). In the described embodiment, the width (W) of the tapered waveguide ends increases from one side to the array of input/output waveguides to the other, so as to keep the separation(s) between the input/output waveguides.

Abstract: An arrayed waveguide grating (AWG) device (1) comprising a substrate having a first array of waveguide (8) optically coupled between first and second slab couplers (3,4) and a second array of input-output waveguides (10) optically coupled at first ends thereof to an input/output side (5) of the second slap-coupler (43). The input/output waveguide are tapered at first end portions (13) thereof so as to increase in width towards the second slap coupler, and the width (W) of the first ends of the input/output waveguides varies across the second array (10) in a manner so as to increase uniformity of at least on performance parameter, for example adjacent crosstalk (AXT).

Abstract: An optical power monitor comprises; an array waveguide grating comprising first and second optical interaction regions between which an input optical signal propagates from a first position on a first side of the first optical interaction regions to a second position on a second side of the second optical interaction region, a correspondence between said first and second positions depending upon a wavelength of the optical signal, there being a plurality of array waveguides coupled between a second side of the first optical interaction region and a first side of the second optical interaction region, and a plurality of output waveguides coupled at one end to the second side of the second optical interaction region for outputting different wavelength channel outputs from the second optical interaction region; and detectors for detecting said different wavelength channel outputs at the other ends of the output waveguides; wherein the plurality of output waveguides include at least two output waveguides for at l

Abstract: A phasar (arrayed waveguide grating) including a segmented waveguide disposed between the phasar and one of the single-mode waveguides on either the input or output side of the phasar. The segmented waveguide is optimized to produce a flattened passband of the phasar, thereby minimizing variations in the phasar spectral response. The optimization may be performed by an evolutionary algorithm which generates random variations into the design population and selects the better members in a multi-generational selection process. The flattened passband phasar is particularly useful in a wavelength-division multiplexing (WDM) fiber communications network.

Abstract: Arrayed Waveguide Grating with Reduced Crosstalk An Arrayed Waveguide Grating (AWG) having reduced adjacent crosstalk is described. Interspersed ones (21) of the output waveguides of the AWG are of different widths to the remaining output waveguides (23), along corresponding portions of their lengths, preferably in at least an initial portion of the fan-out region. Passband unifonmity is maintained by making all the output waveguides substantially of the same width at the output slab coupler. In the illustrative embodiment, alternate ones of the plurality of output waveguides are tapered to a narrower width (W2) between first and second portions (22,24) thereof and the remaining ones of the output waveguides are of a substantially uniform width (W1) between corresponding first and second portions thereof.

Abstract: A phasar (arrayed waveguide grating) including a segmented waveguide disposed between the phasar and one of the single-mode waveguides on either the input or output side of the phasar. The segmented waveguide is optimized to produce a flattened passband of the phasar, thereby minimizing variations in the phasar spectral response. The optimization may be performed by an evolutionary algorithm which generates random variations into the design population and selects the better members in a multi-generational selection process. The flattened passband phasar is particularly useful in a wavelength-division multiplexing (WDM) fiber communications network.