199 results about "Optical circulator" patented technology

The invention relates to a phase-sensitive optical time domain reflectometer based on multi-frequency reference switching. Continuous laser generated by a continuous laser is divided into a local path and a detection path through an optical coupler; the local path is input to the polarization coherent receiving module, the detection path is incident to a light intensity modulator driven by the signal generation circuit module, and the light intensity modulator is converted into a multi-frequency pulse laser sequence with intensity modulation; the multi-frequency pulse laser sequence enters the sensing optical fiber to be measured through the optical circulator; generated Rayleigh backscattered light and local continuous laser are subjected to beat frequency coherent receiving in a polarization coherent receiving module through a circulator; and the signal acquisition circuit adopts a demodulation algorithm to compensate phase drift and sensitivity difference of detection pulse demodulation signals with different frequencies so as to realize dynamic strain sensing. Compared with the prior art, the phase drift and the sensitivity difference between the frequencies are extracted to realize the compensation of the interleaved signals, and the method does not depend on the fixed reference frequency, so that the robustness and the adaptability of the system in a complex environment are remarkably enhanced.

This invention relates to a Bragg light generation system and method suitable for Bragg-type atomic interferometers. The system includes: a laser for generating a first laser beam with a frequency in a preset atomic absorption peak band; an optical circulator for propagating the first laser beam to a cascaded acousto-optic modulator and receiving two third laser beams returned from the cascaded acousto-optic modulator; a cascaded acousto-optic modulator for diffracting the first laser beam into two second laser beams with opposite propagation directions through Bragg diffraction of two acousto-optic crystals; an optical assembly for performing secondary diffraction on the two second laser beams and reflecting the two mutually perpendicular second laser beams to the cascaded acousto-optic modulator; and an output module for splitting and sampling the two third laser beams and modulating the sampled third laser beams into Bragg laser beams in the target frequency band. This invention reduces the path separation of the two Bragg laser beams by using a quasi-common optical path, thereby reducing phase noise and improving measurement accuracy.

The application discloses a kind of EFPI optical fiber sensor multi-sensor multiplexing temperature-pressure demodulation system and method, including ASE broadband laser, optical circulator, EFPI optical fiber sensor, 2-way wavelength division multiplexer, N-way wavelength division multiplexer, N-way wavelength division demultiplexer, photoelectric detector, FBG, 1*2 optical fiber coupler, optical spectrometer, data processing system;The input port input of the optical circulator is connected with ASE broadband laser, the output port cir2 is connected with two cascaded FBGs, the output port cir3 is connected with EFPI optical fiber sensor, the input port of 2-way wavelength division multiplexer is connected with the output port cir4 of optical circulator, and the output port is connected with N-way wavelength division multiplexer;N-way wavelength division multiplexer is accessed via the input port of 1*2 optical fiber coupler, and outputs two-way signals, one-way is connected with N-way wavelength division demultiplexer via N-way photoelectric detector and data processing system, and the other way is connected with optical spectrometer;N channels are connected by cascaded FBG, and the cascade of N EFPI optical fiber sensors is realized.

The invention discloses a distributed optical fiber two-dimensional vector sensing system and method, the system uses an acousto-optic modulator group and an optical circulator group to ask a plurality of fiber cores of a multi-core optical fiber in parallel, heterodyne coherent detection uses local oscillator light to improve the signal-to-noise ratio, and through the relation between the fiber core position difference and the direction angle of a two-dimensional sound wave in the aspect of algorithm, the two-dimensional sound wave direction angle is obtained. According to the space division multiplexing distributed optical fiber acoustic sensing system, a two-dimensional vector signal is accurately restored, the measurement vector angle range of the space division multiplexing distributed optical fiber acoustic sensing system for two-dimensional sound waves is 0-360 degrees, the vector sensing range is larger than 50 km and far exceeds that of an existing system, and the detection capacity of the distributed optical fiber acoustic sensing system is greatly improved.

The invention discloses an on-chip fully-integrated optical circulator based on phase modulation. The on-chip fully-integrated optical circulator comprises a substrate, a buried oxide layer, an optical waveguide layer, an upper cladding and a metal layer used for manufacturing metal electrodes, the substrate, the buried oxide layer, the optical waveguide layer, the upper cladding and the metal layer are stacked, the optical waveguide layer comprises two input / output optical waveguide groups, a four-port resonant cavity and two metal electrode pairs, and the metal layer comprises four modulation areas; four ports of the resonant cavity are respectively connected with four interfaces of the modulation area, each input / output optical waveguide group is connected by a bent optical waveguide and coupled to the resonant cavity, the middle of the metal electrode pair is bent to form a coplanar waveguide electrode, and the middle of each two ends of the modulation area is connected by the coplanar waveguide electrode. The fully-integrated optical circulator is realized under the silicon-based substrate for the first time, is compatible with current mainstream optical integration platforms such as SOI, LNOI and LTOI, and can be widely applied to large-scale photonic integrated chips, such as the fields of optical communication, optical sensing, on-chip optical interconnection and the like.

An optical circulator includes a first polarization beam splitter member having a common optical port, a second polarization beam splitter member having an emittance optical port and at least two receiving optical ports, and a first polarization adjustment member. The two receiving optical ports respectively receive two linearly polarized light beams. The two linearly polarized light beams respectively pass through the second polarization beam splitter member, and sequentially pass through the first polarization adjustment member and the first polarization beam splitter member to be combined into a first combined light beam for being output from the common optical port. The common optical port receives a compound optical signal that passes through the first polarization beam splitter member to be split into another two linearly polarized light beams that are combined into a second combined light beam for being output.

The application discloses a Stokes parameter encoder, which comprises a fiber optical circulator and an optical path round trip path; a polarization maintaining fiber Faraday rotator is arranged on the optical path round trip path to rotate the polarization of light by 45 degrees; the fiber optical circulator is a polarization maintaining fiber optical circulator; the fiber optical polarization beam splitter is a polarization maintaining fiber optical polarization beam splitter; the delay fiber is a polarization maintaining delay fiber; and the fiber optical phase modulator is a polarization maintaining fiber optical phase modulator. The application further discloses a parameter encoding method of the encoder. The above technical scheme can perfectly offset the rotation angle deviation problem caused by the device, can guarantee the stability of the rotation angle regardless of the angle deviation of the device, is easy to realize the driving circuit, is easy to integrate and small in size due to the pure fiber structure, and can realize the continuous variable quantum key distribution of the complete GG02 protocol based on the Stokes encoder.

The invention discloses an all-fiber three-dimensional tomography system, which is used for performing three-dimensional tomography on an object to be observed at a high speed and comprises a light source, a first optical coupler, a first optical circulator, a first optical collimator, a first convex lens, an electric control attenuator, a second optical circulator, a second optical collimator, a second convex lens, a second optical coupler and a balance detector. The light source included in the all-fiber three-dimensional tomography system can quickly perform line or plane scanning on optical scattering media such as biological tissues and the like by utilizing a technology of capturing optical signals to obtain images and adopting an all-fiber line architecture, so as to obtain high-resolution three-dimensional images.

The application provides a semiconductor laser reservoir pool computing device based on silicon-based micro-resonant cavity optical feedback, and belongs to the technical field of photonic neuromorphic computing. Laser output by a driving laser is modulated by a phase modulator, and then is injected into a response semiconductor laser through a feedback cavity incoupler and a circulator; the output end of the response semiconductor laser is connected to an optical circulator in sequence through a second variable optical attenuator, a polarization controller, a silicon-based micro-resonator and a first variable optical attenuator, so as to form a silicon-based micro-resonator optical feedback loop; the output end of the feedback cavity incoupler is connected to a broadband photodetector, which is used to collect reservoir pool output signals; the phase modulator is loaded with a modulation signal containing an input signal and a random mask, so as to realize input layer signal coding. The application realizes the improvement of overall computing performance.

The application provides a polarization-dependent reflective two-stage optical ring, which comprises a first collimator, a first beam splitting cube, a first optical rotation component, a second beam splitting cube, a third beam splitting cube of a second optical rotation component and a second collimator arranged along a first optical path, and three beam splitting cubes are respectively light splitting dielectric films; the application combines the characteristics of a transmission two-stage ring and a reflective ring, two optical rotation components are arranged on the first optical path from the first collimator to the second collimator, thereby realizing the series connection of two isolation systems, playing a double-stage isolation effect, meanwhile, the application realizes the optical path folding of a second optical path from the second collimator to the third collimator by using a reflective component, and optical components are multiplexed in one of the optical rotation components, thereby also achieving a double-stage isolation effect; while realizing the double-stage isolation effect, the application also reduces the product volume, is beneficial to the integration of equipment and is also beneficial to cost reduction.

The present disclosure describes a single aperture laser range finder (SALRF). In an implementation, the single aperture laser range finder includes a beam extender including an aperture and an input aperture lens. A matching lens collimates light emitted from an emitter element associated with a single aperture optical circulator and received by the beam extender, respectively. A single aperture optical circulator has an emitter channel associated with the emitter element and a detector channel associated with a detector element. The emitter channel and the detector channel merge together at an input / output aperture. A light gating mechanism is configured to permit received light to enter the detector channel and to prevent the received light from entering the emitter channel. The SALRF has an electronics end cap.

The application discloses a microwave photon filter and a control method thereof, and belongs to the field of optical fiber communication. The filter comprises an optical ring cavity, a tunable laser source, an electro-optic intensity modulator, a photoelectric detector and an electric vector network analyzer. The first input end of the electro-optic intensity modulator is connected with the output end of the tunable laser source, the second input port of the electro-optic intensity modulator is connected with the output end of the electric vector network analyzer, and the output end of the electro-optic intensity modulator is connected with the input end of an optical circulator in the optical ring cavity. The output end of the optical circulator in the optical ring cavity is connected with the input end of the photoelectric detector, and the output end of the photoelectric detector is connected with the input end of the electric vector network analyzer. The application can overcome the problem that the device parameters cannot be adjusted after the structure of the microwave photon filter is determined.

The application belongs to the technical field of optical fiber preparation automation, and specifically discloses a femtosecond laser-based optical fiber grating automatic processing and sorting system and method. The system comprises a sorting unit, a processing unit and a detection unit. The sorting unit comprises a feeder for automatically feeding optical fibers during processing, a winding machine connected with the feeder through an optical fiber and used for packaging and winding the finished optical fibers, and an industrial robot used for sorting the packaged finished optical fibers. The processing unit is arranged between the feeder and the winding machine and is used for processing optical fiber gratings. The detection unit comprises a test light source, an optical circulator, an optical spectrum analyzer and a loss module. The optical circulator is connected with the test light source, the optical spectrum analyzer and the optical fiber on the feeder. The loss module is arranged between the processing unit and the winding machine and blocks the propagation of test laser emitted by the test light source in the optical fiber through a bent optical fiber. The control unit is in communication connection with the processing unit, the sorting unit and the detection unit and is used for realizing optical fiber grating automatic processing and sorting.

The invention discloses an active mode demultiplexing module which comprises a mode converter, two optical circulators and a bidirectional semiconductor optical amplifier. The mode converter is used for converting a high-order mode into a fundamental mode to complete primary mode demultiplexing, fundamental mode signals after primary demultiplexing are injected into the bidirectional semiconductor optical amplifier through the two optical circulators from the positive direction and the negative direction respectively, and the signals after being shaped by the bidirectional semiconductor optical amplifier are output by the corresponding optical circulators. A bidirectional symmetrical injection structure is formed, different propagation is beneficial to separation of different signals, and mutual interference, namely mode crosstalk, between forward and reverse signals can be effectively reduced, so that a mode demultiplexing function is better completed, and an output signal has higher signal quality than a primary demultiplexing signal. Besides, by optimizing and adjusting the driving current of the bidirectional semiconductor optical amplifier or an auxiliary optical pumping mode, not only can the gain of the mode channel be dynamically adjusted, but also the power balance of the mode channel and the demultiplexing of a high extinction ratio mode can be realized; the method is especially suitable for receiving few-mode signals in a mode division multiplexing (MDM) optical transmission system and constructing optical switching nodes in a multi-dimensional multiplexing optical network.

To provide an optical transmission device, an optical transmission system, and an optical transmission method that suppress an OSNR penalty due to return light.SOLUTION: An optical transmission device disposed at a fiber end of a single-core optical fiber and used when signal light is bidirectionally transmitted through the optical fiber, the optical transmission device comprising an optical transmitter configured to transmit first signal light in one direction belonging to the signal light, an optical receiver configured to receive second signal light in a reverse direction belonging to the signal light, and a controller configured to guide the first signal light transmitted from the optical transmitter to the optical fiber, An optical circulator configured to guide the second signal light from the optical fiber to the optical receiver; and a light source configured to output, to the optical fiber, excitation light that Raman-amplifies the second signal light to second optical power higher than first optical power of the first signal light.SELECTED DRAWING: Figure 2

A temperature strain separable dynamic and static combined measurement distributed optical fiber sensing system, comprising: laser, optical modulator, radio frequency signal generator, optical filter, DFB laser, polarization controller, first acoustooptic modulator, depolarizer, erbium-doped fiber amplifier, two optical circulators, optical wavelength division multiplexer, receiving module, signal acquisition and processing module are arranged in sequence, the application carries out temperature sensing to the back Raman scattering light of the pulse while receiving the Rayleigh scattering light of the detection pulse, and controls the time interval of adjacent pump pulse and detection pulse to carry out three-bit pulse coding and decoding, so that the back Raman scattering signals of individual pulse in pulse pair are separated in time, and finally the simultaneous measurement of dynamic variable (vibration) and static variable (temperature, static strain) is realized and the spatial resolution of measurement is ensured not to be lost.

The invention discloses a transmitting and receiving synchronous switching method and system based on an optical circulator. According to the invention, by acquiring the spatial position coordinates of the MEMS optical switch and the optical circulator control unit and calculating the length of the electric signal transmission path, the accurate and synchronous adjustment of the trigger time is realized, the influence of environmental factors on the transmission path is eliminated in combination with a temperature compensation mechanism, and the accuracy of a time delay compensation value is ensured; a multi-dimensional state space infrastructure and a grading judgment mechanism are established, and regional division and grading strategy formulation can be performed by integrating multi-dimensional states such as optical power, temperature, electromagnetic interference and switching success rate, so that the system can dynamically adjust a switching strategy according to a real-time operation state; the problem of delay jitter caused by electromagnetic interference of master-slave triggering in a traditional synchronization method is avoided, the problem of high switching failure rate caused by switching speed difference and control time sequence difference of the optical circulator and the MEMS optical switch is effectively solved, fine control over the switching process is achieved, and the adaptability and reliability of the system under different environment conditions are improved.

The invention discloses a time delay reserve pool calculation method based on dispersion orthogonal polarized light feedback VCSEL. An adopted time delay RC system comprises a tunable laser, a Mach-Zehnder modulator, a VCSEL, an optical isolator, an optical coupler, a polarization controller, a variable optical attenuator, a chirp fiber Bragg grating and a photoelectric detector. A signal of the input layer is modulated by a Mach-Zehnder modulator and then is injected into an X polarization component of the VCSEL of the reserve pool layer; emitted light of the VCSEL is divided into two paths after passing through the optical circulator, one path is reflected back to the VCSEL by the chirp fiber bragg grating after being subjected to cross-polarization rotation through the polarization controller, and a reserve pool layer of the time delay RC system is constructed; one path is transmitted to the output layer and is converted into an electric signal through a photoelectric detector. According to the method, the time delay characteristic can be further inhibited, so that generation of harmful resonance is further inhibited, and the method has stronger nonlinear characteristic and better calculation performance.

The invention provides a parameter measurement device and method for a terahertz wave beam, and the device comprises a laser signal generation module which is used for generating a combined laser signal; the to-be-tested terahertz continuous wave radiator outputs a terahertz continuous wave signal based on the combined laser signal; the scanning modulation module is used for carrying out beam scanning and modulation on the terahertz continuous wave signal based on the combined laser signal to generate a reflected laser signal; the optical circulator is used for outputting the combined laser signal to the scanning modulation module and outputting the reflected laser signal to the current signal generation module; the current signal generation module generates a current signal based on the reflected laser signal; and a control and data processing module. The parameter measuring device of the terahertz wave beam is based on all-fiber detection, does not need a spatial light path system which is large in size and difficult to adjust, is high in integration level and simple to operate, can realize non-intrusive terahertz wave beam near-field measurement, and can realize ultra-wideband terahertz wave beam measurement.

The invention belongs to the technical field of lasers. The invention provides an all-fiber laser with adjustable pulse width and a pulse width tuning method. The all-fiber laser comprises a narrow-band dissipation soliton mode-locked fiber laser seed source, a first fiber isolator, a fiber amplifier, a second fiber isolator, an optical circulator and a dispersion element which are sequentially arranged along a light path. The seed source generates a mode-locked pulse with a fixed initial spectral width; the nonlinear effect intensity is controlled by adjusting the driving current of the pumping source, so that the spectrum broadening amount of the pulse in the amplification process is regulated and controlled, the variable total spectrum width is formed, the spectrum width is subjected to linear time-frequency mapping through a dispersion element with a fixed group delay dispersion value, and finally continuous and electric control adjustment of the output pulse width is achieved. The whole system adopts an all-fiber structure, has the advantages of high stability, compact structure, good tuning linearity and the like, and is suitable for industrial processing, sensing and scientific research application scenes needing flexible pulse width regulation and control.

an optical intensity modulation device (100) comprising: an optical modulator (102) operative to modulate a continuous wave optical carrier signal at a carrier wavelength to generate one or more sidebands on the optical carrier signal; a radio frequency (RF) signal generator (104) operative to provide an RF drive signal to the optical modulator; a first optical waveguide grating (108) having a center reflection wavelength corresponding to the sidebands; and an optical circulator (106) configured to direct the optical carrier signal and the one or more sidebands into the first optical waveguide grating and to direct a reflected optical signal from the first optical waveguide grating towards an output to form an output optical signal, wherein the RF signal generator is operative to switch the drive signal on and off to form an intensity modulated output optical signal.

According to the optical transceiver assembly, the optical fiber connector and the optical module provided by the invention, lenses are arranged at three ports of an optical circulator, so that multiple beams of laser emitted by multiple optical ports of a sending end can be collimated into collimated light through the lenses, and the multiple beams of collimated light share the optical circulator for optical path propagation. The number of optical circulators in the optical transceiver assembly is reduced, and miniaturization design of the optical transceiver assembly is facilitated.

The present invention provides an integrated distributed optical fiber sensing system comprising: an on-chip integrated laser (1), an injection locking unit (3), a distributed feedback laser (2), a semiconductor optical amplifier (5), an optical circulator (6), a sensing optical fiber (7), and a coherent detection unit (4), wherein the on-chip integrated unit (10a) is obtained by on-chip integration of the injection locking unit (3) and the coherent detection unit (4).

This invention provides a low-crosstalk signal demodulation device and method for fiber optic laser communication, belonging to the field of fiber optic communication technology. The device includes a fiber optic signal input port, an optical circulator, a polarization beam splitter / combiner module, a balanced photodetector unit, a low-noise amplification and quadrature demodulation module, an adaptive crosstalk cancellation unit, a MIMO equalization and decision unit, and a digital signal output port, connected in series according to the signal flow direction. It also includes a crosstalk monitoring and feedback unit bidirectionally connected to the low-noise amplification and quadrature demodulation module, the adaptive crosstalk cancellation unit, and the MIMO equalization and decision unit. This invention, employing the aforementioned low-crosstalk signal demodulation device and method for fiber optic laser communication, overcomes the limitations of traditional single-domain crosstalk suppression. Through the synergistic effect of optical path, circuit, and algorithm layers, it effectively suppresses crosstalk caused by multi-channel multiplexing, polarization mode dispersion, and backscattering, significantly improving demodulation accuracy, anti-interference capability, and system stability.

The invention provides a photoelectric oscillator capable of being used for generating tunable phase coding microwave pulses. The photoelectric oscillator is composed of a tunable laser, a polarization controller, a phase modulator, a dual-drive Mach-Zehnder modulator, an optical circulator, a phase shift fiber bragg grating, a single-mode fiber, a photoelectric detector, an electric amplifier, a microwave source and an arbitrary waveform generator. The invention develops the active mode-locked photoelectric oscillator for generating the phase-coded microwave pulse signal, which is simple in structure and good in tunability. On the basis of an active mode-locked optoelectronic oscillator, a phase modulator is driven by a phase coding signal, so that the duration of each voltage polar code is kept consistent with the loop delay of the optoelectronic oscillator, and a phase-coded coherent microwave pulse sequence is generated. The signal has the advantage of large time bandwidth product, can give consideration to the detection distance and distance resolution of the radar, and has the characteristics of interference resistance, low interception and the like.

The application discloses a dense optical fiber coding method based on an optical switch and a weak reflectivity grating string, and comprises the following steps: 1, a light source module emits a C-band pulse signal, and the signal contains optical pulses with different central wavelengths and overlapping in a time domain; 2, a weak reflectivity grating string is used to code each node to obtain different wavelength pulse combination types, and the coding signals of different coding nodes on the same link are spaced apart in the time domain; 3, the coding signal is injected into an array waveguide grating through an optical circulator, and is decomposed into more than one single-wavelength pulse signal; 4, a detector array and a collection card are used to carry out photoelectric conversion on the coding pulse signal, and the collected signal is output to an FPGA and an upper computer for processing and display; the problems that the prior art cannot be applied to realize real-time coding of a large-scale and high-reliability all-optical network and that the real-time coding scale is limited and cannot meet the use requirements of a large-scale network are solved.

The application discloses a kind of based on microwave field and light field demodulation's fiber grating distributed measurement device and method, measurement device includes broadband light source, polarizer, polarization controller, electro-optic modulator, vector network analyzer, first radio frequency amplifier, 1:99 beam splitter, bias control board, first erbium-doped fiber amplifier, optical circulator, 1x2 optical fiber coupler, transmission optical fiber, FBG array sensing optical fiber, photodetector, second radio frequency amplifier, computer, second erbium-doped fiber amplifier, fiber grating demodulator.The application can realize the spatial continuous distributed measurement of temperature / strain / pressure and the like parameters of fiber along line and high spatial resolution point distribution measurement.

An integrated optical circulator comprising at least two single-fiber bidirectional optical fiber interfaces, a refractive element group, an optical isolation element group, and an optical fiber array, wherein the refractive element group and the optical isolation element group are sequentially arranged on a same optical path; incident signal light from each optical fiber interface sequentially passes through the refractive element group and the optical isolation element group, then is output by a corresponding outgoing optical fiber of the optical fiber array; incident signal light from each incident optical fiber of the optical fiber array sequentially passes through the optical isolation element group and the refractive element group, then is emitted by a corresponding optical fiber interface. Multiple optical circulators are integrated within the volume of a same optical circulator, reducing the volume occupied by optical circulators, lowering overall cost of the device, and improving convenience of optical path integration.

The invention provides a substrate deformation measurement system based on a fiber bragg grating (FBG) and a self-adaptive layout method thereof. The substrate deformation measurement system comprises an FBG sensor network, a data acquisition module, a signal preprocessing and data analysis processing module and a visual interface, the FBG sensor network comprises a measured substrate and a fiber grating string; the data acquisition module comprises a tunable broadband light source, an optical isolator, an optical circulator, a signal transmission optical fiber, a spectrum analyzer and a corresponding demodulation algorithm; the signal preprocessing and data analysis processing module comprises hardware equipment and computer software; and the visual interface uses Labview to write a front-end interface, and is used for performing three-dimensional real-time display on a substrate shape reconstruction result and realizing an alarm function for special situations. According to the invention, through fusion of real-time data and a prior model, focusing monitoring and resource optimization configuration of a key area are realized, and the problems of high calculation complexity, low data processing efficiency and the like in a traditional distributed fiber grating morphology sensing technology are solved.

The invention discloses a hybrid integrated correction-free linear frequency modulation DFB laser ranging system and a ranging method thereof, and relates to the technical field of laser radar ranging. Comprising a hybrid integrated packaging module, a first DFB laser, a second DFB laser, an optical circulator unit, a GPPO high-frequency radio frequency interface and an independent regulation and control unit, the first DFB laser, the second DFB laser and the optical circulator unit are packaged in the hybrid integrated packaging module, and the GPPO high-frequency radio frequency interface is arranged on the hybrid integrated packaging module; according to the hybrid integrated correction-free linear frequency modulation DFB laser ranging system and the ranging method thereof, the sweep frequency linearity of the laser is directly anchored on a radio frequency source of an electric domain through a physical mechanism of sideband locking, so that the sweep frequency linearity of output optical frequency is ensured from the physical level; a complex digital pre-distortion algorithm or expensive photoelectric phase-locked loop hardware is thoroughly omitted, and the system complexity is greatly reduced.