Abstract: Planar assemblies for coupling a plurality of optical transceivers to the same optical fiber. For example, the optical transceivers may be PON transceivers functioning according to different data rates and/or different modulation formats. Each optical transceiver communicates using one or more different wavelength channels. At least some of the disclosed planar assemblies are scalable to couple various numbers of optical transceivers to the same end face of an optical fiber, e.g., by fixing a corresponding number of passive, slab-like optical filters to a substantially planar surface of the support substrate to which the optical transceivers are also fixed adjacent and along. Some embodiments may employ various bulk lenses fixed to said planar surface to suitably relay light-beam segments between the end face of the fiber and the optical transceivers and/or between the different slab-like optical filters.

Abstract: Planar assemblies for coupling a plurality of optical transceivers to the same optical fiber. For example, the optical transceivers may be PON transceivers functioning according to different data rates and/or different modulation formats. Each optical transceiver communicates using one or more different wavelength channels. At least some of the disclosed planar assemblies are scalable to couple various numbers of optical transceivers to the same end face of an optical fiber, e.g., by fixing a corresponding number of passive, slab-like optical filters to a substantially planar surface of the support substrate to which the optical transceivers are also fixed adjacent and along. Some embodiments may employ various bulk lenses fixed to said planar surface to suitably relay light-beam segments between the end face of the fiber and the optical transceivers and/or between the different slab-like optical filters.

Abstract: An optical line card includes a plurality of coherent receivers and a plurality of optical modulators. The coherent receivers are each configured to receive a corresponding channel of a received optical superchannel. The optical modulators are each configured transmit a corresponding channel of a transmitted optical superchannel. Each of a plurality of optical splitters is configured to receive a corresponding one of a plurality of unmodulated optical signals from an optical source external to the line card. Each splitter directs a first portion of light received by that splitter to a corresponding one of the coherent receivers, and a second portion of light received by that splitter to a corresponding one of said optical modulators.

Abstract: An apparatus, including: an optical sensor fiber having a first end optically couplable to receive light from a light source, wherein the optical sensor fiber is a multimode optical fiber configured to carry light in different spatial propagating modes, wherein the optical sensor fiber is constructed such that environmental fluctuations couple light energy between some of the spatial propagating modes; a spatial propagating mode demultiplexer optically coupled to a second end the optical sensor fiber and configured to separate a plurality of light signals received from different ones of the spatial propagating modes; and an optical receiver configured to process the separated light signals and to estimate a longitudinal position of one of the environmental fluctuations along the optical sensor fiber based a measured delay between arrival times of the separated light signals.

Abstract: Disclosed herein are various embodiments of an optical cross-connect switch in which optical beamforming is used to generate desired (e.g., technically beneficial) beam profiles at the beam-steering element of the switch. An example beam profile that can be generated in this manner is a substantially rectangular beam profile generated from an input optical beam having a substantially Gaussian beam profile. The use of rectangular beam profiles may be beneficial because such beam profiles can be used to increase the optical fill factor of the beam-steering element of the switch, thereby enabling the switch to have a higher number of optical ports and/or a lower cost per optical port than comparable conventional optical cross-connect switches. In an example embodiment, the disclosed optical cross-connect switch can be used to implement a wavelength-selective optical router.

Abstract: An optical line card includes a plurality of coherent receivers and a plurality of optical modulators. The coherent receivers are each configured to receive a corresponding channel of a received optical superchannel. The optical modulators are each configured transmit a corresponding channel of a transmitted optical superchannel. Each of a plurality of optical splitters is configured to receive a corresponding one of a plurality of unmodulated optical signals from an optical source external to the line card. Each splitter directs a first portion of light received by that splitter to a corresponding one of the coherent receivers, and a second portion of light received by that splitter to a corresponding one of said optical modulators.

Abstract: An optical line card includes a plurality of coherent receivers and a plurality of optical modulators. The coherent receivers are each configured to receive a corresponding channel of a received optical superchannel. The optical modulators are each configured transmit a corresponding channel of a transmitted optical superchannel. Each of a plurality of optical splitters is configured to receive a corresponding one of a plurality of unmodulated optical signals from an optical source external to the line card. Each splitter directs a first portion of light received by that splitter to a corresponding one of the coherent receivers, and a second portion of light received by that splitter to a corresponding one of said optical modulators.

Abstract: Disclosed herein are various embodiments of an optical cross-connect switch in which optical beamforming is used to generate desired (e.g., technically beneficial) beam profiles at the beam-steering element of the switch. An example beam profile that can be generated in this manner is a substantially rectangular beam profile generated from an input optical beam having a substantially Gaussian beam profile. The use of rectangular beam profiles may be beneficial because such beam profiles can be used to increase the optical fill factor of the beam-steering element of the switch, thereby enabling the switch to have a higher number of optical ports and/or a lower cost per optical port than comparable conventional optical cross-connect switches. In an example embodiment, the disclosed optical cross-connect switch can be used to implement a wavelength-selective optical router.

Abstract: An optical line card includes a plurality of coherent receivers and a plurality of optical modulators. The coherent receivers are each configured to receive a corresponding channel of a received optical superchannel. The optical modulators are each configured transmit a corresponding channel of a transmitted optical superchannel. Each of a plurality of optical splitters is configured to receive a corresponding one of a plurality of unmodulated optical signals from an optical source external to the line card. Each splitter directs a first portion of light received by that splitter to a corresponding one of the coherent receivers, and a second portion of light received by that splitter to a corresponding one of said optical modulators.

Abstract: A wavelength-selective cross-connect (WSXC) device configured to route any set of carrier wavelengths from a corresponding input port to any selected output port. The WSXC device comprises a diffraction grating and a beam-steering device optically coupled to one another and to the input/output ports using astigmatic optics. The astigmatic optics includes one or more cylindrical lenses configured to image one beam-steering surface onto another beam-steering surface to enable a continuous spectral response. The astigmatic optics may further include (i) a cylindrical Fourier lens that enables the WSXC device to convert a change in the angular beam steering performed by the beam-steering device into a corresponding image-spot displacement at the output ports and/or (ii) one or more cylindrical lenses configured to image the active surface of the beam-steering device onto the diffraction grating. Various unfolded configurations of the various embodiments of the WSXC device are also disclosed.

Abstract: An apparatus includes a plurality of input optical couplers and a plurality of output optical couplers. The input optical couplers are placed in a pattern to receive light from multiple locations of an end face of an input multimode optical fiber (MMOF). The output optical couplers are placed in a pattern to provide light to multiple locations of an end face of an output MMOF. The apparatus further includes a plurality of single-mode optical paths. Each of the paths is connected to a corresponding one of the input optical couplers and a corresponding one of the output optical couplers.

Abstract: A wavelength-selective cross-connect (WSXC) device having N input ports and M output ports and configured to route any set of one or more carrier wavelengths from a corresponding input port to any selected output port. In one embodiment, the WSXC device includes a diffraction grating and a beam-steering device optically coupled to each other and to the input/output ports so that each of the carrier wavelengths traverses the diffraction grating and the beam-steering device two or more times en route from the respective input port to a designated output port. Various unfolded configurations of the WSXC device are also disclosed.

Abstract: A system, e.g. a reconfigurable electro-optical network, includes input and output waveguides. The input waveguide is configured to receive a first input optical signal including a first modulated input wavelength channel. The output waveguide is configured to receive a carrier signal including an unmodulated output wavelength channel. An input microcavity resonator is configured to derive a modulated electrical control signal from the modulated input wavelength channel. A first output microcavity resonator is configured to modulate the output wavelength channel in response to the control signal.

Abstract: A WDM device having a controller that individually controls the operating parameters of tunable lasers and the temperatures of an optical multiplexer and etalon. The device employs a spectral analyzer to measure the spectral composition of the optical output signal produced by the device. Based on the analyses of the measured spectral composition, the controller sets the temperatures of the tunable lasers, optical multiplexer, and optical etalon to values that cause: (i) middle frequencies of transmission bands of the optical multiplexer to be spectrally aligned with the corresponding frequencies of the specified frequency grid, (ii) each laser line to be properly positioned within the corresponding transmission band, and (iii) transmission resonances of the optical etalon to be properly positioned with respect to the laser lines.

Abstract: A WDM device having a controller that individually controls the operating parameters of tunable lasers and the temperatures of an optical multiplexer and etalon. The device employs a spectral analyzer to measure the spectral composition of the optical output signal produced by the device. Based on the analyses of the measured spectral composition, the controller sets the temperatures of the tunable lasers, optical multiplexer, and optical etalon to values that cause: (i) middle frequencies of transmission bands of the optical multiplexer to be spectrally aligned with the corresponding frequencies of the specified frequency grid, (ii) each laser line to be properly positioned within the corresponding transmission band, and (iii) transmission resonances of the optical etalon to be properly positioned with respect to the laser lines.

Abstract: A passive arrayed-waveguide-grating (AWG) router that can be used to implement the dual functionality of a wavelength router and a 3-dB power splitter for one of its wavelength channels while functioning as a conventional wavelength router for the other wavelength channels. The passive AWG router can advantageously be used, e.g., in a WDM-PON system to reduce the insertion-loss disparity between the various wavelength channels that are being used to broadcast optical signals from an optical line terminal located at the service provider's central office, through the passive AWG router, to a plurality of optical network units located near the end users.

Abstract: An optical-power-distribution (OPD) subsystem that provides means for supplying optical local-oscillator signals and optical-carrier signals to various optical line cards, without the need for each optical line card to have a corresponding individual laser source. In one embodiment, a single laser coupled to the OPD subsystem provides optical local-oscillator signals and optical-carrier signals to multiple optical line cards. In another embodiment, multiple lasers coupled to the OPD subsystem provide multiple optical local-oscillator signals and optical-carrier signals to a single line card. An OPD subsystem may provide significant power savings in the operation of the corresponding optical transport system, a reduction in the required equipment-cooling capacity, and an increase in the device-packing density within optical line cards and inside equipment cabinets that house optical line cards.

Abstract: A wavelength-selective cross-connect (WSXC) device configured to route any set of carrier wavelengths from a corresponding input port to any selected output port. The WSXC device comprises a diffraction grating and a beam-steering device optically coupled to one another and to the input/output ports using astigmatic optics. The astigmatic optics includes one or more cylindrical lenses configured to image one beam-steering surface onto another beam-steering surface to enable a continuous spectral response. The astigmatic optics may further include (i) a cylindrical Fourier lens that enables the WSXC device to convert a change in the angular beam steering performed by the beam-steering device into a corresponding image-spot displacement at the output ports and/or (ii) one or more cylindrical lenses configured to image the active surface of the beam-steering device onto the diffraction grating. Various unfolded configurations of the various embodiments of the WSXC device are also disclosed.

Abstract: An optical transmitter that uses half-rate electrical signals, without multiplexing them to the full rate, to generate a full-rate optical duobinary signal. In one embodiment, an optical transmitter of the invention has a Mach-Zehnder modulator (MZM) driven by two half-rate electrical data streams. A first half-rate data stream is applied to drive a first arm of the MZM. A delay element misaligns a second half-rate data stream that is synchronized with the first data stream by one half of a bit period, and the resulting misaligned data stream is applied to drive a second arm of the MZM. The MZM is configured to (i) transmit substantially no light from the feeding laser when the applied data streams have the same binary value and (ii) have a maximum transmission when the applied data streams have different binary values, thereby generating a full-rate optical duobinary signal at its output.

Abstract: An apparatus includes a plurality of input optical couplers and a plurality of output optical couplers. The input optical couplers are placed in a pattern to receive light from multiple locations of an end face of an input multimode optical fiber (MMOF). The output optical couplers are placed in a pattern to provide light to multiple locations of an end face of an output MMOF. The apparatus further includes a plurality of single-mode optical paths. Each of the paths is connected to a corresponding one of the input optical couplers and a corresponding one of the output optical couplers.