A device includes a module comprising an arrayed waveguide grating (AWG), and a filter having a filter input port, a filter output port, and a filter COMM output port. The filter is operable such that a first range of wavelengths entering the filter at the filter input port is directed to the filter output port and a second range of wavelengths entering the filter at the filter input port is directed to the COMM output port. The AWG includes an AWG input port optically coupled to the filter output port to receive the first range of wavelengths, and a plurality of AWG output ports.

A common component assembly is provided for a cable joint for joining a first submarine optical cable and a second submarine optical cable. The assembly includes a first end face including a first opening and a first flange for connection to a first cable termination unit of an undersea optical cable joint. The assembly also includes a second end face including a second opening and a second flange for connection to a second cable termination unit of an undersea optical cable joint. The assembly further includes a fiber tray connecting the first end face to the second end face. In addition, the assembly includes an optical assembly connected to a first side of the fiber tray. The optical assembly includes a free space optical add/drop multiplexer.

An optical system can automatically lock an adjustable spectral filter to a first wavelength of an incoming light signal, and can automatically filter an additional incoming light signal at the first wavelength. A tunable filter can have a filtering spectrum with an adjustable peak wavelength and increasing attenuation at wavelengths away from the adjustable peak wavelength. The tunable filter can receive first input light, having a first wavelength, and can spectrally filter the first input light to form first output light. A detector can detect at least a fraction of the first output light. Circuitry coupled to the detector and the tunable filter can tune the tunable filter to maximize a signal from the detector and thereby adjust the peak wavelength to match the first wavelength. The tunable filter further can receive second input light and spectrally filter the second input light at the first wavelength.

An electro-optic system, the electro-optic system that may include an input port that is configured to receive a bandpass signal that conveys information; wherein the bandpass signal is a radio frequency (RF) signal; an optical carrier source that is configured to generate an optical carrier signal having an optical carrier frequency; at least one electrical bias circuit that is configured to generate at least one electrical bias signal; an electro-optic modulation circuit that is linear at the optical field; a manipulator that is configured to (a) receive the at least one electrical bias signal and the bandpass signal, (b) generate, based on the at least one electrical bias signal and the bandpass signal, at least one modulating signal; wherein the electro-optic modulation circuit is configured to modulate the optical carrier by the at least one modulating signal to provide an output optical signal that comprises at least one optical pilot tone and at least one optical sideband that conveys the information.

An M×N wavelength selective switch (WSS), may comprise a common port fiber array unit (FAU) configured to emit optical beams with a lateral offset and a beam steering device configured to direct optical beams with an angular offset to add/drop port optical fibers of an add/drop port FAU. The common port FAU may comprise a first set of common port optical fibers arranged in a first column of the common port FAU and a second set of common port optical fibers arranged in a second column of the common port FAU. The second column of the common port FAU may be laterally offset from the first column of the common port FAU. The beam steering device may be configured to selectively direct, in two dimensions, the optical beams with the angular offset to the add/drop port optical fibers.

An optical system can automatically lock an adjustable spectral filter to a first wavelength of an incoming light signal, and can automatically filter an additional incoming light signal at the first wavelength. A tunable filter can have a filtering spectrum with an adjustable peak wavelength and increasing attenuation at wavelengths away from the adjustable peak wavelength. The tunable filter can receive first input light, having a first wavelength, and can spectrally filter the first input light to form first output light. A detector can detect at least a fraction of the first output light. Circuitry coupled to the detector and the tunable filter can tune the tunable filter to maximize a signal from the detector and thereby adjust the peak wavelength to match the first wavelength. The tunable filter further can receive second input light and spectrally filter the second input light at the first wavelength.

This application provides example optical switching methods and example apparatuses. One example method includes generating K images that are consecutive in time sequence, where a first wavelength channel and at least one second wavelength channel are switched to a blocking state through a same image in the K images, and a value of K depends on a quantity of times that attenuation adjustment is performed for switching the first wavelength channel from a normal state to the blocking state. Information about the K images can then be sent to an optical switching element to enable the optical switching element to perform attenuation adjustment on the first wavelength channel and the at least one second wavelength channel.

An M×N wavelength selective switch (WSS), may comprise a common port fiber array unit (FAU) configured to emit optical beams with a lateral offset and a beam steering device configured to direct optical beams with an angular offset to add/drop port optical fibers of an add/drop port FAU. The common port FAU may comprise a first set of common port optical fibers arranged in a first column of the common port FAU and a second set of common port optical fibers arranged in a second column of the common port FAU. The second column of the common port FAU may be laterally offset from the first column of the common port FAU. The beam steering device may be configured to selectively direct, in two dimensions, the optical beams with the angular offset to the add/drop port optical fibers.

To provide an optical branch coupler which facilitates communizing the design of an optical transmission path, the optical branch coupler comprising: a first add drop unit for outputting a third optical signal to a first line in which a first optical signal received from the first line and a second optical signal inserted into the first line are multiplexed and outputting the first optical signal; and a second add drop unit for receiving the first optical signal, receiving a sixth optical signal from a second line different from the first line in which a fourth optical signal and a fifth optical signal dropped from the second line are wavelength multiplexed, demultiplexing the fourth and fifth optical signals, and outputting a seventh optical signal to the second line in which the fourth optical signal and the first optical signal transmitted by the first add drop unit are multiplexed.

Systems and methods for integrated band splitter for scaling a dual band Reconfigurable Optical Add/Drop Multiplexer (ROADM). A degree in a ROADM includes ROADM components including a line port and a plurality of connection ports; channel multiplexer/demultiplexer components including degree ports and local add/drop ports; and one or more band splitters in between the ROADM components and the channel multiplexer/demultiplexer components. The band splitter can be configured to split/combine C-band spectrum and L-band spectrum. The band splitter can be a passive fiber device.