Abstract: In some implementations, a Mach-Zehnder interferometer (MZI) includes a delay line arm formed in a chip and a mirrored facet formed in the chip. The delay line arm may be configured to propagate light to the mirrored facet. The mirrored facet may be configured to reflect, to the delay line arm, a percentage of the light propagated to the mirrored facet by the delay line arm.

Abstract: An optical device includes a waveguide device and a fiber stub. The fiber stub at least partially contains a first optical fiber and is directly attached to the waveguide device by an adhesive. The first optical fiber is to be coupled to a second optical fiber included in an optical connector when the optical connector is inserted into a receptacle of the optical device. The fiber stub is to couple the first optical fiber to at least one of the waveguide device or an optical waveguide included in the waveguide device.

Abstract: According to some possible implementations, an optical device may include a plurality of photodiodes, wherein alignment of the plurality of photodiodes with a fixed separation to a plurality of multi-mode waveguides disposed on an optical waveguide chip and with the same fixed separation is optimized by alignment of at least one of the plurality of photodiodes to at least one single-mode waveguide and translation of the optical waveguide chip relative to the plurality of photodiodes by a fixed offset of the at least one single-mode waveguide relative to the plurality of multi-mode waveguides.

Abstract: An optical device includes a waveguide device and a fiber stub. The fiber stub at least partially contains a first optical fiber and is directly attached to the waveguide device by an adhesive. The first optical fiber is to be coupled to a second optical fiber included in an optical connector when the optical connector is inserted into a receptacle of the optical device. The fiber stub is to couple the first optical fiber to at least one of the waveguide device or an optical waveguide included in the waveguide device.

Abstract: According to some possible implementations, an optical device may include a plurality of photodiodes, wherein alignment of the plurality of photodiodes with a fixed separation to a plurality of multi-mode waveguides disposed on an optical waveguide chip and with the same fixed separation is optimized by alignment of at least one of the plurality of photodiodes to at least one single-mode waveguide and translation of the optical waveguide chip relative to the plurality of photodiodes by a fixed offset of the at least one single-mode waveguide relative to the plurality of multi-mode waveguides.

Abstract: A spot size converter may include a tapered periodic segmented waveguide (PSW). The tapered PSW may include a plurality of waveguide segments defined by a plurality of gaps between the plurality of waveguide segments. The plurality of gaps may be at one or more angles that are not substantially parallel to a direction of a width of the tapered PSW. The direction of the width of the tapered PSW may be substantially perpendicular to a direction in which light passes through the tapered PSW.

Abstract: A 1×N demultiplexer may include an input slab to distribute an input beam, including one or more wavelengths of light, among waveguides of a waveguide array. The wavelengths of light may comprise TE polarized light and TM polarized light. The 1×N demultiplexer may include the waveguide array to propagate a plurality of beams via the waveguides. The 1×N demultiplexer may include an output slab to cause N TE polarized beams and N TM polarized beams to be formed based on the plurality of beams. The 1×N demultiplexer may include a set of N TE output ports and a set of N TM output ports coupled to the output slab. A TE output port may receive a TE polarized beam of the N TE polarized beams. A TM output port may receive a TM polarized beam of the N TM polarized beams.

Abstract: A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.

Abstract: A spot size converter may include a tapered periodic segmented waveguide (PSW). The tapered PSW may include a plurality of waveguide segments defined by a plurality of gaps between the plurality of waveguide segments. The plurality of gaps may be at one or more angles that are not substantially parallel to a direction of a width of the tapered PSW. The direction of the width of the tapered PSW may be substantially perpendicular to a direction in which light passes through the tapered PSW.

Abstract: A spot size converter may include a tapered periodic segmented waveguide (PSW). The tapered PSW may include a plurality of waveguide segments defined by a plurality of gaps between the plurality of waveguide segments. The plurality of gaps may be at one or more angles that are not substantially parallel to a direction of a width of the tapered PSW. The direction of the width of the tapered PSW may be substantially perpendicular to a direction in which light passes through the tapered PSW.

Abstract: A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.

Abstract: A spot size converter may include a tapered periodic segmented waveguide (PSW). The tapered PSW may include a plurality of waveguide segments defined by a plurality of gaps between the plurality of waveguide segments. The plurality of gaps may be at one or more angles that are not substantially parallel to a direction of a width of the tapered PSW. The direction of the width of the tapered PSW may be substantially perpendicular to a direction in which light passes through the tapered PSW.

Abstract: New architectures for multicast switches, and other optical switches and splitters, that have substantially reduced insertion loss, crosstalk and better overall optical performance in comparison to existing optical switches and splitters. Optimized waveguide mesh layouts are used to substantially reduce the number of waveguide crossings, which reduces insertion loss. The reduction in the number of crossings also reduces the complexity of the mesh and provides better crossing angles to reduce crosstalk and other issues. Instead of crossing all of the waveguides connected between splitter outputs and switch inputs, the waveguides are crossed in sets of waveguides.

Abstract: A wavelength selective device including an arrayed waveguide grating is disclosed. The wavelength selective device includes a MEMS mirror, which couples light from an input port to an elongate aperture of an input star coupler or slab of the arrayed waveguide grating. A controller tilts the MEMS mirror in response to a sensed temperature change of the arrayed waveguide grating, thereby lessening a sensitivity of the arrayed waveguide grating to the temperature change. The MEMS mirror can also be tilted to shift wavelengths of the wavelength channels of the arrayed waveguide grating by pre-defined amounts upon receiving a corresponding remote command.

Abstract: A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.

Abstract: A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.

Abstract: New architectures for multicast switches, and other optical switches and splitters, that have substantially reduced insertion loss, crosstalk and better overall optical performance in comparison to existing optical switches and splitters. Optimized waveguide mesh layouts are used to substantially reduce the number of waveguide crossings, which reduces insertion loss. The reduction in the number of crossings also reduces the complexity of the mesh and provides better crossing angles to reduce crosstalk and other issues. Instead of crossing all of the waveguides connected between splitter outputs and switch inputs, the waveguides are crossed in sets of waveguides.

Abstract: A tunable optical filter is configured to take point measurements at a few optical frequencies per frequency channel of a DWDM optical network. The measurement frequencies are shifted by pre-determined amounts relative to the optical frequency channel being characterized. Since the spectral shape of the tunable optical filter is known, the center optical frequency, the modulation bandwidth, and the total optical power of the channel can be obtained from as few as three optical measurements. The center optical frequency and the total optical power can be continuously monitored by providing a tunable filter stage coupled to an interleaver stage, and computing a ratio and a weighted sum the optical signals at the two outputs of the interleaver stage.

Abstract: A wavelength selective device including an arrayed waveguide grating is disclosed. The wavelength selective device includes a MEMS mirror, which couples light from an input port to an elongate aperture of an input star coupler or slab of the arrayed waveguide grating. A controller tilts the MEMS mirror in response to a sensed temperature change of the arrayed waveguide grating, thereby lessening a sensitivity of the arrayed waveguide grating to the temperature change. The MEMS mirror can also be tilted to shift wavelengths of the wavelength channels of the arrayed waveguide grating by pre-defined amounts upon receiving a corresponding remote command.

Abstract: A tunable optical filter is configured to take point measurements at a few optical frequencies per frequency channel of a DWDM optical network. The measurement frequencies are shifted by pre-determined amounts relative to the optical frequency channel being characterized. Since the spectral shape of the tunable optical filter is known, the center optical frequency, the modulation bandwidth, and the total optical power of the channel can be obtained from as few as three optical measurements. The center optical frequency and the total optical power can be continuously monitored by providing a tunable filter stage coupled to an interleaver stage, and computing a ratio and a weighted sum the optical signals at the two outputs of the interleaver stage.