Abstract: An optical filter includes a near-infrared absorbing layer including a first material, the first material being configured to absorb light in a first wavelength spectrum belonging to a near-infrared wavelength spectrum. The optical filter includes a compensation layer adjacent to the near-infrared absorbing layer, the compensation layer including a second material different from the first material. The optical filter includes a metamaterial structure spaced apart from the near-infrared absorbing layer via the compensation layer, the metamaterial structure being configured to absorb or reflect light in a second wavelength spectrum at least partially overlapped with the first wavelength spectrum.

Abstract: A beamforming element comprises an imprinting-shifting component configured to imprint an input signal onto a second beam to form an imprinted beam and adjust the optical phase of the imprinted beam; one or more multi-beam optical couplers configured to receive a phase-shifted imprinted beam and a first beam and form an interference beam from the combination thereof; and one or more optical-to-electrical converter components configured to receive an interference beam and generate an electrical signal based thereon that includes the beamforming time delay(s) and is frequency up/down-converted with respect to the input signal.

Abstract: A method for improving wide-band wavelength-tunable laser. The method includes configuring a gain region between a first facet and a second facet and crosswise a PN-junction with an active layer between P-type cladding layer and N-type cladding layer. The method further includes coupling a light excited in the active layer and partially reflected from the second facet to pass through the first facet to a wavelength tuner configured to generate a joint interference spectrum with multiple modes separated by a joint-free-spectral-range (JFSR). Additionally, the method includes configuring the second facet to have reduced reflectivity for increasing wavelengths. Furthermore, the method includes reconfiguring the gain chip with an absorption layer near the active layer to induce a gain loss for wavelengths shorter than a longest wavelength associated with a short-wavelength side mode. Moreover, the method includes outputting amplified light at a basic mode via the second facet.

Abstract: Disclosed are a dual-carrier integrated optical device and a photoelectric module. The optical device comprises: an encapsulation unit, and a ceramic substrate and two independent carrier assemblies arranged in the encapsulation unit. Every carrier assembly comprises a DWDM active chip arranged on the first heat sink, a first heat sink arranged on the independent control element, and an independent control element for adjusting the temperature of the DWDM active chip to adjust an output wavelength of the DWDM active chip. The DWDM active chip and the independent control element are respectively connected to the ceramic substrate. According to the characteristic that the wavelength of the active chip will shift with the temperature, an output laser wavelength of each active chip is independently controlled by means of the independent control element, which achieves higher wavelength stability and can realize optical signal transmission at different rates.

Abstract: A system can include a splitter configured to receive a first optical signal carrying first data and generate a first optical signal copy and second optical signal copy. Also included is at least one optical processing path includes at least one optical encoder configured to transform the first optical signal copy into a second optical signal carrying the first data and an additional optical feature not present in the first optical signal, at least one optical modulator configured to optically modulate the second optical signal according to a compare data to generate an optical match signal that indicates matches between the compare data and the first data, and at least one photodetector configured to generate an electrical match signal in response to the optical match signal. Corresponding methods are also disclosed.

Abstract: A photonic system enabling the processing of high frequency microwave, mm-wave, THz signals or other RF signals. The processing may include, e.g., adjusting the frequency, quadrature, and/or power of the signals. In illustrative examples, the system uses a polychromatic light source producing at least two low noise optical emission frequencies that can be independently tuned in a broad frequency range and/or modulated in a broad frequency range using external modulators. An RF input signal is upconverted to one of the optical harmonics of the modulated polychromatic source, processed in the optical frequency domain, and downconverted to the RF domain (at the same or a different RF carrier frequency). The photonic system can be integrated on a planar optical substrate, such as a photonic integrated circuit (PIC). Optical local oscillators are also described for use in the photonic system or for other purposes. Various system, device, and method examples are provided.

Abstract: Examples described herein relate to an optical device having a photonic-crystal lattice structure. In some examples, the optical device may include a substrate having a photonic-crystal lattice structure. The optical device may further include an optical waveguide formed in the photonic-crystal lattice structure and a defect cavity formed in the photonic-crystal lattice structure and optically coupled to the optical waveguide. Furthermore, the optical device may include a refractive index tuning structure adjacent to the defect cavity in the photonic-crystal lattice structure.

Abstract: Embodiments relate to a bidirectional free space optical (FSO) communications system. Specifically, data-encoded FSO beams are transmitted and received between two terminals. A transmit (Tx) direction of a beam transmitted from the first terminal is dithered by a beam steering unit (BSU). As the dithered beam is received by the second terminal, the power levels of the beam are measured. The power levels are then encoded in a data-encoded FSO beam transmitted to the first terminal. This allows the first terminal to decode the received FSO beam and determine the power levels. The power levels allow the first terminal to determine Tx direction misalignments and adjust the Tx direction for the Tx beam sent to the second terminal. This process may be repeated to reduce Tx misalignments and may be performed by both terminals such that each terminal sends power level information to the opposite terminal.

Abstract: An optical filter includes a light absorbing layer and a conductive nanodisk. The light absorbing layer includes a near-infrared absorbing material configured to absorb light of a first wavelength spectrum within a near-infrared wavelength spectrum. The conductive nanodisk is configured to absorb or reflect light of a second wavelength spectrum within the first wavelength spectrum. An image sensor includes the optical filter, a camera module includes the optical filter, and an electronic device includes the optical filter.

Abstract: A compact laser source and a single sideband modulator used therein is disclosed. The compact laser source includes a seed laser and one or more channels, with each channel generating one or more output laser beams having corresponding different wavelengths. The compact laser source can be formed in whole or in part on a single optical motherboard to thereby minimize space and power requirements. By employing the disclosed single sideband modulator, harmonics in the generated output laser beams can be minimized. The compact laser source finds application in an atom interferometer (AI) system, which may be used to measure gravity, acceleration, or rotation of the AI system.

Abstract: An electronic assembly including first circuit board, second circuit board, and optical communication component. First circuit board includes first board and first connector. First connector is fixed on first board. Second circuit board includes second board and second connector. Second connector is fixed on second board. Optical communication component includes first communication card, first light-emitting component, second communication card, first photodetector and optical-fiber cable. First communication card is plugged into first connector. First light-emitting component is fixed on and electrically connected to first communication card. Second communication card is plugged into second connector. First photodetector is fixed on and electrically connected to second communication card. Two opposite ends of optical-fiber cable are respectively fixed to first communication card and second communication card to respectively be optically coupled to first light-emitting component and first photodetector.

Abstract: Aspects of the present disclosure are directed to wavelength division multiplexing systems comprising arrays of spectrally selective devices that are arranged on a substrate to compensate for perturbations of the spectral characteristics of the devices due to factors such as temperature non-uniformity, inherent spectral non-uniformity, and the like. As a result, shifts in the center wavelengths and/or changes in the wavelength spacing for the wavelength channels of a WDM system due to such perturbations are mitigated. In some embodiments, an array of spectrally selective devices is arranged on a substrate such that their respective wavelength channels are not linearly correlated with their physical position within the array, enabling the devices to be arranged in pairs that are subject to substantially the same environmental conditions and/or operate on nearly the same spectral range.

Abstract: An optical functional device includes a package case accommodating an optical functional element, an input optical fiber, and an output optical fiber. The optical functional device includes a first reflecting surface that reflects input light output from the input optical fiber to an optical path of output light, a second reflecting surface that reflects the input light to the optical functional element, and a third reflecting surface that reflects the output light in a direction in which the output light becomes further away from an optical axis of the input optical fiber. An optical axis of a leaked light beam transmitted through the second reflecting surface after being reflected by the first reflecting surface or an extension line of the optical axis in an optical propagation medium does not include a portion that is aligned with an optical axis of the output light reflected by the third reflecting surface.

Abstract: An optical module includes: a first lens and a second lens provided between a light emitter and a light receiver; and a base member on which the light emitter and the light receiver are placed, and each of the first lens and the second lens is fixed via an adhesive resin. A first bonding direction in which a first bonding surface of the first lens is bonded and fixed via an adhesive resin, and a second bonding direction in which a second bonding surface of the second lens is bonded and fixed via an adhesive resin are respectively perpendicular to an optical axis direction of light, and an orientation of the first bonding surface and an orientation of the second bonding surface make are different from each other.

Abstract: A packaged integrated white light source configured for illumination and communication or sensing comprises one or more laser diode devices. An output facet configured on the laser diode device outputs a laser beam of first electromagnetic radiation with a first peak wavelength. The first wavelength from the laser diode provides at least a first carrier channel for a data or sensing signal.

Abstract: According to some aspects, a transmissive and all-dielectric optical component/limiter with great cutoff efficiency using Vanadium Dioxide (VO2) as the active component is disclosed. In some embodiments, Vanadium dioxide is used for an optical limiter due to the large contrast in optical constants upon undergoing the semiconductor to metal phase transition. When triggered optically, this transition occurs within 60 fs, making the device suitable for an ultrafast laser environment. In addition, the phase transition threshold is tunable by applying stress or doping; therefore, the device cutoff intensity can be adjusted to fulfill specific requirements.

Abstract: An optical communication system comprises an optical communication device and an optical power supply configured to generate a sequence of optical frame templates directed to the optical communication device. The optical communication device may use the received optical frame templates as a light source for generating data-loaded optical frames and/or may extract from the optical frame templates control information encoded therein using one or more headers thereof.

Abstract: An optical communication system comprises an optical communication device and an optical power supply configured to generate a sequence of optical frame templates directed to the optical communication device. The optical communication device may use the received optical frame templates as a light source for generating data-loaded optical frames and/or may extract from the optical frame templates control information encoded therein using one or more headers thereof.

Abstract: Optical network systems and components are disclosed, including a transmitter comprising a digital signal processor receiving a plurality of independent data streams, and supplying a plurality of digital subcarrier outputs, based on the plurality of independent data streams, and configurable to vary the frequency spacing between two or more of the plurality of digital subcarrier outputs; the transmitter configured to output a modulated optical signal including a plurality of optical subcarriers based on the digital subcarrier outputs wherein based on first ones of the plurality of digital outputs, the first one of the plurality of subcarriers is spectrally spaced from the second one of the plurality subcarriers by a first gap, and based on second ones of the plurality of digital outputs, the first one of the plurality of subcarriers is spectrally spaced from the second one of the plurality of subcarriers by a second gap different than the first.

Abstract: Certain aspects, configurations, embodiments, and examples of a spectrometer with a compact design are described. In some implementations, the spectrometers according to the present disclosure may be used for optical emission spectroscopy (OES). The spectrometer architecture and imager described herein allows a single detector, compact, and high-throughput spectrometer. One or more aspects include an Echelle grating in a spectrometer that reuses optical surfaces to separate wavelengths of light. For example, in one or more aspects, a reflective triplet telescope acts as both a collimator and imager. By reusing optical components, the relative size of the spectrometer may be reduced.

Abstract: [Problem] To provide an optical transmission device that, while suppressing band narrowing due to optical filters, achieves flexibility of optical communication such as wavelength reutilization and that supports a flexible grid. [Solution] An optical transmission device according to the present invention is provided with a cyclic AWG that filters respective optical signals inputted to each input port. The respective optical signals are constituted so that a plurality of wavelength-multiplexed signals can be allocated within one channel band, the respective optical signals are filtered in channel units, and the pass-band width of each of the input ports of the cyclic AWG corresponds to the bandwidth of a channel.

Abstract: In various embodiments, wavelength beam combining systems feature multiple beam emitters each emitting an individual beam, as well as multiple micro-optics arrangements each disposed optically downstream from a beam emitter to intercept the beam emitted thereby and direct the beam toward a dispersive element for combination into a multi-wavelength output beam.

Abstract: The invention relates to a coaxial direct-detection LIDAR system for measuring velocity, temperature and/or particulate density. The system comprises a laser source for emitting a laser light beam having a lasing center frequency along an emission path. The system further comprises an optical delivery system arranged in the emission path of the laser source, the optical delivery system being arranged for delivering the laser light beam in a measuring direction, the optical delivery system further being configured for collecting a return signal backscattered along the measuring direction. Finally, the system comprises a detector system arranged to receive the return signal from the optical delivery system, the detector system comprising a narrowband optical filter and a detector, the narrowband optical filter having a filter center frequency of a pass-band, wherein the center lasing frequency and/or the center filter frequency may be scanned.

Abstract: There is provided a driver circuit including a variable current-source configured to include, a first current-source coupled to a first input node to which a first signal is input from an external, a second current-source coupled to a second input node to which a second signal as an inversion of the first signal is input from the external, a first bypass circuit coupled between the first current-source and the first input node, the first bypass circuit being switched according to the second signal, and a second bypass circuit coupled between the second current-source and the second input node, the second bypass circuit being switched according to the first signal, and a terminal circuit configured to be terminated for an optical device driven by a drive signal according to the first signal, the drive signal being output from an output node coupled between the terminal circuit and the variable current-source.

Abstract: A lighting device includes: a DC power supply circuit which supplies a light-emitting element with a first voltage; a signal generation circuit which generates a control signal based on a visible light communication signal; a current control element which is connected in series to the light-emitting element and turned on and off based on the control signal; a DC power supply control circuit which causes a second voltage at a first node between the light-emitting element and the current control element to be a constant value, by controlling the DC power supply circuit based on the second voltage; and a first feedback circuit which supplies the DC power supply control circuit with the second voltage. The first feedback circuit supplies the DC power supply control circuit with a predetermined voltage in a period in which the current control element is off.

Abstract: According to one embodiment, a current-mode driver provides pre-emphasis for a transmitter. The current-mode driver includes a filtering circuit comprising a resistor, an inductor, and a capacitor. The filtering circuit is operable to receive a data signal and produce a filtered data signal. The filtering circuit may be tuned to produce a ringing frequency with an underdamped transient decay in the filtered data signal that compensates for signal degradation caused by the optical transmitter. The current-mode driver may also include a current source coupled to the filtering circuit. The current source may be operable to generate a compensation signal based on the filtered data signal that is capable of driving the transmitter.

Abstract: A variable impedance circuit (2) has an impedance device and is connected in series with a light source (A1). A switch circuit (Q1) is connected in parallel with the variable impedance circuit (2). A first controller (3) is configured to perform ON and OFF control of the switch circuit (Q1) and thereby to modulate an intensity of an illumination light emitted from the light source (A1). An impedance-varying circuit (Q2) is connected with the variable impedance circuit (2). The second controller (4) is configured to control the impedance-varying circuit (Q2) to change the impedance of the variable impedance circuit (2). The first controller (3) and the second controller (4) share a common hardware.

Abstract: Disclosed is a transmitter optical module which includes a first package generating an optical signal; a second package bonded with the first package by using chip-to-chip bonding, having a silicon optical circuit platform structure, and amplifying the optical signal; and an optical waveguide forming a transmission path of the optical signal from the first package to the second package.

Abstract: An optical transmission device includes a receiver that receives first light, a transmitter that outputs second light, a memory, a processor coupled to the memory, configured to control a first optical level of the second light in such a way that a second optical level calculated based on an optical level of the received first light and an optical level of the second light that is output from the transmitter becomes a predetermined target value, a combiner that combines the received first light and the second light for which the first optical level is controlled by the processor, and an amplifier that amplifies the combined light.

Abstract: The present invention provides an optical apparatus, which is configured to output image information and comprises a housing; a light source; an optical device; an optical device earner, wherein the optical device is mounted on the optical device carrier and positioned on one side of the optical device carrier; a support plate positioned on the other side of the optical device carrier and being one part of the housing; and a connecting piece, wherein one end of the connecting piece penetrates the support plate and then is connected with the optical device carrier, and the relative positions of the connecting piece and the support plate are fixed.

Abstract: In one embodiment, an apparatus for optical communication is disclosed. An optical sub-assembly and optical platform may form the apparatus. Lasers contained in the hermetically sealed optical sub-assembly can be coupled to a modulator on the optical platform. The optical modulator can access an optical network using beams of light sent from the laser.

Abstract: Filters shaped differently from those commonly used in WDM Mux/DeMux optical devices are described. Different from the prior art devices that commonly use filters shaped in cuboid, the filters in the embodiment of the present invention are shaped in parallelepiped. In other words, a cross section of such filter is not in parallelogram. According to one embodiment of the present invention, a filter is so cut that a cross section thereof presents a cutting angle not being 90 degrees. As a result, the filter is fully used in WDM Mux/DeMux optical devices. Such filters are advantageously used in compact optical modules.

Abstract: An optical device includes a gain medium on a substrate. The device also includes one or more laser cavities and an amplifier on the substrate. The one or more laser cavities each guides a light signal through a different region of the gain medium such that each of the light signals is amplified within the gain medium. The amplifier guides an amplified light signal through the gain medium such that the amplified light signal is amplified in the gain medium.

Abstract: The invention discloses a method for improving luminous intensity adaptability and a device thereof, relating to photo-electronic communication field. In the method, the device is configured with more than one level load resistors, the device collects voltage value and if the device collects predetermined numbers of voltage values which meet some requirement, it computes an average value of all collected voltage values, sets voltage value according to the average value, determines whether the set voltage is satisfied with a predetermined requirement, if yes, collects data according to the set voltage; otherwise, switches the load resistor according to a predetermined rule, in which the load voltage has influence on collecting voltage. The invention has advantages of improving luminous intensity adaptability of a screen when collecting optical signal and reducing rate of error codes.

Abstract: A surface emitting semiconductor laser includes a substrate, a first conductivity-type first semiconductor multilayer reflector, an active layer, a semiconductor layer, a second conductivity-type second semiconductor multilayer reflector that includes a current confinement layer, and a heat dissipating metal member. At least the first semiconductor multilayer reflector, the active layer, the semiconductor layer, and the second semiconductor multilayer reflector are stacked in this order on the substrate. A columnar structure having a top portion, a side surface, and a bottom portion is formed from the second semiconductor multilayer reflector to the semiconductor layer. The heat dissipating metal member is connected to the semiconductor layer exposed at the bottom portion of the columnar structure.

Abstract: A wavelength-selectable laser device generally includes an array of laser emitters and a filtered external cavity for filtering light emitted from the laser emitters and reflecting different wavelengths back to each of the laser emitters such that lasing occurs at different wavelengths for each of the laser emitters. Each laser emitter includes a gain region that emits light across a plurality of wavelengths including, for example, channel wavelengths in an optical communication system. The filtered external cavity may include a dispersive optical element that receives the light from each of the laser emitters at different angles and passes or reflects different wavelengths of the light at different angles such that only wavelengths associated with the respective laser emitters are reflected back to the respective laser emitters. By selectively emitting light from one or more of the laser emitters, one or more channel wavelengths may be selected for lasing and transmission.

Abstract: A multi-laser transmitter optical subassembly may include N number of lasers, where each laser is configured to generate an optical signal with a unique wavelength. The transmitter optical subassembly may further include a focusing lens and a filter assembly. The filter assembly may combine the optical signals into a combined signal that is received by the focusing lens. The filter assembly may include N?1 number of filters. Each of the filters may pass at least one of the optical signals and reflect at least one of the optical signals. The filters may be low pass filters, high pass filters, or a combination thereof.

Abstract: A modulating apparatus includes a branch that branches input light; a first modulating unit that modulates the phase of a first branch obtained by the branch; a second modulating unit that modulates a second branch obtained by the branch; a third modulating unit that is connected in series to the first modulating unit, transmits the first branch without branching the first branch, modulates the phase of light transmitted by controlling a refractive index of the light transmitted; a fourth modulating unit that is connected in series to the second modulating unit, transmits the second branch without branching the second branch, and modulates the phase of a light transmitted by controlling a refractive index of the light transmitted; and a coupler that couples the first branch modulated by the first and the third modulating units and the second branch modulated by the second and the fourth modulating units, at different intensities.

Abstract: A tunable laser with multiple in-line sections including sampled gratings generally includes a semiconductor laser body with a plurality of in-line laser sections configured to be driven independently to generate laser light at a wavelength within a different respective wavelength range. Sampled gratings in the respective in-line sections have the same grating period and a different sampling period to produce the different wavelengths. The wavelength of the light generated in the respective laser sections may be tuned, in response to a temperature change, to a channel wavelength within the respective wavelength range. By selectively generating light in one or more of the laser sections, one or more channel wavelengths may be selected for lasing and transmission. By using sampled gratings with the same grating period in the multiple in-line sections, the multiple section tunable laser may be fabricated more easily.

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: An optical transmitter for an optical communication system includes a light source that outputs optical signals having a plurality of wavelengths, and a wavelength control unit. The wavelength control unit receives an optical signal from the light source, resonates an optical signal having a first wavelength, modulates the optical signal of the first wavelength with a first transmission data signal to obtain an intensity modulated optical signal, and outputs the intensity modulated optical signal. The wavelength control unit may be integrally formed on a semiconductor substrate in which a high thermal conductivity material is used. Alternatively, a trench that intercepts external heat may be formed in a boundary surface of the wavelength control unit, and may be filled with a low thermal conductivity material.

Abstract: A thin-film Light Emitting Diode (LED) and methods of manufacturing the same are disclosed. Specifically, the thin-film LED is provided with an epitaxial layer having a proton implantation that controls the size of the active volume. Controlling the size of the active volume enables the thin-film LED to enjoy decreased rise and fall times, thereby achieving a thin-film LED that is useable for transmission in high transmission rate communication systems.

Abstract: The present application is directed to a laser system using Stimulated Raman Scattering and harmonic conversion to produce a continuous wave ultraviolet wavelength output signal. More specifically, the laser system includes a pump source configured to generate at least one pump signal, a resonant cavity resonant at a Stokes wavelength in optical communication with the pump source, a SRS gain device positioned within the resonant cavity and configured to generate at least one SRS output signal at a Stokes wavelength when pumped with the pump signal, and a harmonic conversion device positioned within the resonant cavity and configured to produce a continuous wave second harmonic output signal of the SRS output signal.

Abstract: A heated laser package generally includes a laser diode, a heating resistor and a transistor in a single laser package. The heating resistor and transistor form a heating circuit and may be located on a submount adjacent to the laser diode. The transistor is configured to control the drive current to the heating resistor and any additional heat generated by the transistor may contribute to the heating of the laser diode and thus increase the thermal efficiency of the system. The heated laser package may be used in a temperature controlled multi-channel transmitter optical subassembly (TOSA), which may be used in a multi-channel optical transceiver. The optical transceiver may be used in a wavelength division multiplexed (WDM) optical system, for example, in an optical line terminal (OLT) in a WDM passive optical network (PON).

Abstract: An optical apparatus comprising an optical source for providing output light for providing input signal light can comprise a pump source for pumping a four wave mixing (FWM) process with light pulses (“FWM pump light”); a FWM element in optical communication with said pump source, said FWM element configured for hosting the FWM process to generate, responsive to the FWM pump light, pulses of FWM signal light and FWM idler light having different wavelengths; and a laser or amplifier optical device comprising a gain material for providing optical gain at a gain wavelength via a process of stimulated emission responsive to optical pumping with pump light, said laser or amplifier optical device in optical communication with said optical source and receiving one of the FWM signal light and the FWM idler light as input signal light having the gain wavelength for optically seeding with input signal light the laser or amplifier optical device.

Abstract: In some examples, a transmit assembly is described that may include a first optical transmitter, a second optical transmitter, and a polarizing beam combiner. The first optical transmitter may be configured to emit a first optical data signal centered at a first frequency. The second optical transmitter may be configured to emit a second optical data signal centered at a second frequency offset from the first frequency by a nominal offset n. The polarizing beam combiner may be configured to generate a dual carrier optical data signal by polarization interleaving the first optical data signal with the second optical data signal. An output of the polarizing beam combiner may be configured to be communicatively coupled via an optical transmission medium to a polarization-insensitive receive assembly.

Abstract: An optical apparatus for use in an optical communications network, and a method of operating a network are described. The apparatus includes an input suitable for receiving a first continuous wave optical signal from a remote location on a network, and a modifying unit arranged to modify the first continuous wave optical signal to produce a second continuous wave optical signal having a wavelength which is different from the wavelength of the first continuous wave optical signal. A modulating unit is arranged to modulate the second continuous wave optical signal with data to produce a modulated second continuous wave optical signal.

Abstract: An optical transmission device includes a splitter configured to have at least a first port, a second port, and a third port that output branched input light, branching ratios of the first port and the second port being variable, and a controller configured to reduce an optical level of output light from the first port to be monitored and increase an optical level of output light from the second port according to the reduced optical level of output light from the first port by controlling the branching ratios.

Abstract: A manner of mitigating the self heating effect of a laser or other light source such as a laser in a network node of a communication network. A self-heating mitigation module is provided, the self-heating mitigation module includes one or both of a self-heating adjustment module to accelerate self heating at the beginning of a transmission and a sub-threshold lasing module that applies a sub-threshold current between transmissions. The self-heating adjustment module and the sub-threshold lasing module are preferable both used together and driven by a common signal, for example the burst_enable signal that facilitates transmission from the light source.

Abstract: An interferometer is provided that includes a first path and a second path. The first path is configured to propagate an electro-magnetic signal at a first wavelength. The second path is configured to convert a portion of the electro-magnetic signal from the first wavelength to a second wavelength for processing and is configured to convert the portion of the electro-magnetic signal from the second wavelength back to the first wavelength for interference with the electro-magnetic signal of the first path. The first wavelength may be an optical wavelength or any other suitable wavelength of the electro-magnetic spectrum. The second wavelength, which is different than the first wavelength, also may be any suitable wavelength of the electro-magnetic spectrum.