312 results about "Polarization controller" patented technology

The invention relates to the technical field of laser ranging, in particular to a double-optical-comb hybrid ranging device which comprises a signal detection optical path system and a signal demodulation optical path system. Wherein the signal detection optical path system comprises a first optical frequency comb, a first optical isolator, a first optical collimator, a first beam splitter prism, a reference mirror, a Faraday rotator, a convergence mirror and a target reflector; the signal demodulation optical path system comprises a second optical frequency comb, a second optical isolator, a second optical collimator, a half-wave plate, a second beam splitter prism, a third beam splitter prism, a first polarization controller, a first photoelectric detector, a reflector, a polarization beam splitter prism, a second polarization controller and a second photoelectric detector. A third polarization controller; and a third photoelectric detector. According to the invention, three ranging technologies of asynchronous optical sampling ranging, multi-heterodyne interference ranging and synthetic wavelength ranging are fused, and the problem that a large ranging range and high ranging precision cannot be simultaneously considered in the ranging process is solved.

The invention discloses a high-tolerance synchronous dual-band pulse laser, and relates to the field of lasers, and the laser comprises a first resonant cavity and a second resonant cavity; the first resonant cavity comprises a first pumping source and an optical annular cavity formed by sequentially connecting a first wavelength division multiplexer, a first thulium-doped optical fiber, a first optical coupler, a first isolator, a second wavelength division multiplexer, a high-nonlinearity saturable absorber, a third wavelength division multiplexer and a first polarization controller; the second resonant cavity comprises a second pumping source and an optical annular cavity which is formed by sequentially connecting a fifth wavelength division multiplexer, a second erbium-doped fiber, a second optical coupler, a second wavelength division multiplexer, a high-nonlinearity saturable absorber, a third wavelength division multiplexer, an electric control adjustable delay line, a fourth wavelength division multiplexer, a second polarization controller and a second isolator, and the fifth wavelength division multiplexer, the second erbium-doped fiber, the second optical coupler, the high-nonlinearity saturable absorber, the third wavelength division multiplexer, the electric control adjustable delay line, the fourth wavelength division multiplexer, the second polarization controller and the second isolator; and the first optical coupler and the second optical coupler respectively output synchronization pulses in the wave bands of 2 microns and 1.5 microns. The device is compact in structure, low in manufacturing cost, convenient to operate and capable of covering the mid-infrared band of 2 microns.

An optical frequency domain reflectometer with environmental disturbance resistance and large strain measurement capability belongs to the field of distributed optical fiber sensing and comprises an opposite sweep frequency light frequency modulation continuous wave signal generation module, a light splitting device, a modulation device, a circulator, a polarization controller, an optical coupling device, a photoelectric conversion module and a data acquisition and processing module. An optical signal generated by an opposite sweep frequency light frequency modulation continuous wave signal generation module is divided into probe light and local oscillation light through a light splitting device, the probe light is modulated through a modulation device and sent to an optical fiber through a circulator, and a Rayleigh back scattering light signal generated by the optical fiber and the local oscillation light interfere in an optical coupling device to obtain interference light; the photoelectric conversion module mixes beat frequency signals of interference light, and the data acquisition and processing module analyzes and processes the beat frequency signals. According to the invention, the position information of the Rayleigh backscattering point is marked by using the modulated probe light, the Rayleigh scattering signal at the corresponding position is restored, crosstalk between channels is inhibited, and high-precision measurement in a large dynamic range and resistant to environmental disturbance is realized.

The invention discloses a vector flow velocity measuring device and method based on a bidirectional scanning spectral domain optical coherence tomography technology. Comprising a super light-emitting diode light source, an optical fiber coupler, a polarization controller, an interferometer comprising a sample arm and a reference arm, and a collimating lens, the collimating lens, the grating, the focusing lens group and the linear array camera are sequentially connected through a light path; the linear array camera, the computer and the two-dimensional galvanometer are sequentially connected through a line; according to the method, the fixed bias vector velocity is introduced by utilizing the bidirectional scanning technology, the dynamic light scattering optical coherence tomography method and the Doppler optical coherence tomography method are combined, decoupling of each parameter of the vector flow velocity is efficiently and accurately realized, and a quantitative index is provided for vector flow velocity analysis. The vector flow velocity measuring device based on the bidirectional scanning spectral domain optical coherence tomography technology is simple in system setting and low in cost, the time resolution is improved by about 2.5 times, and the measuring time is shorter.

The invention discloses a confocal full-Mueller matrix imaging device and method based on an optical fiber metasurface array, and belongs to the technical field of polarized optical imaging. The device comprises an optical fiber array multi-polarization illumination module, a sample scanning module, a scattered light transmission module, a metasurface array polarization modulation module and a polarized light intensity detection module. The polarization states of four beams of light are regulated and controlled through the optical fiber polarization controller, and four illumination focal spots in different polarization states are generated on a sample plane at the same time; sample scattered light is modulated by a polarization measurement metasurface array comprising four independent metasurface units, and the polarization state of each path of optical signals is projected to sixteen polarized light spots which are spatially separated; and finally, acquiring light spot intensity information by an area array detector, and reconstructing a full-Mueller matrix image of the sample through calculation. According to the invention, full-Mueller matrix information can be obtained through single scanning, and the device has the characteristics of high resolution, compact structure, good compatibility and the like, and can be used for multi-dimensional polarization microscopic analysis of samples.

The invention discloses a two-photon N00N quantum state intelligent regulation and control device and method, and the device comprises an intelligent regulation and control module, and an entangled photon pair generation module, an HOM interferometer and a data collection module which are connected in sequence, and the entangled photon pair generation module transmits polarized orthogonal entangled photon pairs to two light paths in the HOM interferometer respectively; the data acquisition module is used for detecting and counting photons output by the two light paths respectively; the intelligent regulation and control module controls the first electric control time delay line on one light path and the electric control polarization controller on the corresponding light path so as to regulate the light path difference of the two light paths and the polarization state of photons output by the corresponding light path; every time control is completed, a second electric control time delay line on the other light path is controlled to carry out time delay scanning according to a set rule, and a coincidence counting rate and HOM visibility are obtained; and according to the coincidence counting rate and the HOM visibility, determining whether the two-photon N00N quantum state generated under the control is good or bad. According to the invention, intelligent regulation and control of the two-photon N00N quantum state quality can be realized.

The invention discloses a photon-assisted microwave signal time-frequency amplitude-phase measurement system and method, and the system is characterized in that a pulse light source outputs a light pulse which enters an input end dispersive medium to complete pulse broadening, and then the light pulse enters an electro-optical modulation module; meanwhile, the power divider receives the microwave signal and divides the microwave signal into two paths to be input into an upper sub-modulator and a lower sub-modulator of the electro-optical modulation module so as to modulate optical pulses; a modulated optical signal output by the electro-optical modulation module passes through an output end dispersive medium to complete a time convolution process, then the output optical signal is divided into two paths through the optical coupling module, the two paths sequentially pass through the polarization controller, the polarization beam splitter, the photoelectric detector, the analog-to-digital converter and the digital signal processor, position information and amplitude information of an electric pulse are collected, and the position information and the amplitude information of the electric pulse are obtained. And obtaining time, amplitude, frequency and phase information of the microwave signal. The time, frequency, amplitude and phase information of the microwave signals can be measured at the same time, complex back-end processing is not needed, and the processing speed is high.

The invention discloses an O-band harmonic mode-locked laser based on double-pumping nonlinear polarization evolution, which comprises a first pumping source, a second pumping source, a first wavelength division multiplexer, a second wavelength division multiplexer, a gain fiber, a first polarization controller, a polarization dependent isolator, a second polarization controller and a coupler, which form a bidirectional pumping ring laser resonant cavity. Wherein the first polarization controller and the second polarization controller are arranged on the two sides of the polarization dependent isolator respectively to form a nonlinear polarization evolution mode locking structure together. By improving the power of the double pumping sources and adjusting the polarization state in the cavity, switching from fundamental frequency mode locking to multi-order harmonic mode locking can be achieved, the highest order can reach 33, the repetition frequency upper limit of an O-band all-fiber mode-locked laser is broken through, and the all-fiber mode-locked laser has the advantages of being compact in structure, high in damage threshold, low in cost and easy to integrate all fibers and is suitable for the field of optical communication and the like.

The invention provides an optical feedback resonance enhanced forward Brillouin demodulation structure, which comprises a tunable laser, a first polarization controller, an erbium-doped optical fiber amplifier, an optical coupler, an optical isolator, a forward Brillouin gain optical fiber, a band-pass filter and a photoelectric detector, a second polarization controller; and a spectrum analyzer. The first polarization controller is connected with a port a of the optical coupler, a port b of the optical coupler is connected with an input end of the erbium-doped optical fiber amplifier, an output end of the erbium-doped optical fiber amplifier is connected with the optical isolator, the optical isolator is connected with the band-pass filter, the band-pass filter is connected with the forward Brillouin gain optical fiber, and the optical fiber is fed back to a port c of the coupler through the second polarization controller. The output power of the erbium-doped optical fiber amplifier is controlled, and the polarization states of the pump light and the feedback laser are controlled by the first polarization controller and the second polarization controller, so that the forward Brillouin effect is amplified.

This application provides a semiconductor laser and a terahertz source for generating terahertz waves. The semiconductor laser includes: a substrate; a mesa located on the substrate; and a ridge waveguide and lateral coupling gratings located on the mesa, with the lateral coupling gratings located on both sides of the ridge waveguide. The lateral coupling gratings are configured such that the frequency difference between the fundamental transverse mode wavelength and the second-order transverse mode wavelength of the lasing light emitted by the semiconductor laser is 0.1 THz–10 THz. The semiconductor laser of this application, through the optimized configuration of the ridge waveguide and the lateral coupling gratings on both sides, precisely achieves simultaneous output of the fundamental and second-order transverse modes with a frequency difference on the order of terahertz. Combined with a polarization controller and a nonlinear crystal, it can stably output terahertz waves in the target frequency band. Compared with traditional solutions, the semiconductor laser of this application can simultaneously output the fundamental and second-order transverse modes with a frequency difference on the order of terahertz, offering advantages in miniaturization and low cost.

The application discloses a mode division multiplexing all-optical regenerative device, which comprises a polarization controller, a few-mode amplifier, an optical coupler, a few-mode nonlinear optical fiber, an optical carrier extractor and an optical phase shifter. Mode division multiplexing signals of multi-level pulse amplitude modulation from different users can be simultaneously regenerated by the mode division multiplexing all-optical regenerative device, the regenerated mode division multiplexing signals are amplified and shaped, and the power transfer curve of each mode channel is not affected by the change of other mode levels.

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 invention provides an automatic bidirectional mode-locking fiber laser system, and relates to the technical field of fiber lasers. The system comprises a first electric polarization controller, a second wavelength division multiplexer and a second gain optical fiber which are connected in sequence to form a first gain branch used for realizing laser amplification and polarization state adjustment in an anti-clockwise direction; the second electric polarization controller, the first wavelength division multiplexer and the first gain optical fiber are sequentially connected to form a second gain branch for realizing laser amplification and polarization state adjustment in the clockwise direction; and the third electric polarization controller, the gold nano film and the optical coupler are sequentially connected to form a common branch for simultaneously realizing automatic bidirectional mode locking in the clockwise direction and the anticlockwise direction. The automatic bidirectional mode-locking fiber laser system based on a genetic algorithm and a feedforward neural network is adopted to realize automatic searching and long-term maintenance of a bidirectional single soliton mode-locking state, and is suitable for the fields of double-comb spectrum, double-comb distance measurement, precision spectroscopy and light source programming.

The application discloses a kind of photonic auxiliary microwave signal time-frequency amplitude phase measurement system and method, pulse light source output light pulse in the system enters input end dispersion medium and completes pulse broadening, then enters electro-optic modulation module, simultaneously power divider receives microwave signal and it is divided two-way input electro-optic modulation module in upper and lower sub-modulator to modulate light pulse;The modulated light signal output by the electro-optic modulation module passes through output end dispersion medium, completes time convolution process, after this, output light signal will pass through optical coupling module and be divided into two paths, in turn pass through polarization controller, polarization beam splitter, photodetector, analog-digital converter, digital signal processor, the position information and amplitude information of electric pulse are collected, and the time, amplitude, frequency and phase information of microwave signal are obtained.The application can simultaneously measure the time, frequency, amplitude, phase information of microwave signal, and does not need complex post-processing, and processing speed is fast.

The invention discloses a gas spectrum transparent transmission light path system for hydrogen and hydride, which relates to the technical field of spectral analysis and comprises a wide-spectrum light source module, a multi-pass optical path pool, a film lithium niobate modulation module, a two-dimensional material enhanced micro-ring resonant filter, a Fourier transform infrared spectrometer, a data processing terminal and a polarization controller. The wide-spectrum light source module is used for generating wide-spectrum light signals covering hydrogen and hydride characteristic absorption wavebands; according to the invention, the wide-spectrum light source module covers hydrogen and hydride characteristic absorption in different wavebands, simultaneous detection of multiple components is realized in combination with the wide tuning range of the two-dimensional material enhanced micro-ring resonant filter, wavelength modulation is carried out by utilizing the thin-film lithium niobate modulation module, adjacent absorption peaks are accurately distinguished in cooperation with the transmission bandwidth of the micro-ring filter, and the detection accuracy is improved. In addition, the action path is prolonged through the multi-pass optical path pool, and the detection sensitivity of weak absorption signals is enhanced in combination with pressure control and the corrosion-resistant gas chamber.

This invention provides a multi-wavelength mode-locked fiber laser with adjustable wavelength spacing. It comprises a nonlinear amplifying ring consisting of a pump source (01), a wavelength division multiplexer (02), an erbium-doped fiber (07), a 3km single-mode fiber (08), a three-ring polarization controller (041), a coupler (03), and an optical fiber conduit (12) to achieve pulse mode-locking. A mode selection coupler (05) is used to convert from the fundamental mode to higher-order modes. An improved Sagnac ring consisting of a coupler (06), an optical fiber conduit (17), a three-ring polarization controller (042, 043), and polarization-maintaining fibers (09, 10) is used to achieve multi-wavelength and adjustable wavelength spacing. This multi-wavelength mode-locked fiber laser can achieve multi-wavelength pulsed mode-locked laser with adjustable output wavelength spacing and can be widely used in wavelength division multiplexing, optical communication, optical sensing systems, and other fields.

This invention discloses a simple, multifunctional, integrated 5G analog fronthaul in-band full-duplex communication method for remote units (RUs). This method primarily relates to the fields of optical communication technology and microwave technology. The system structure of the method, as shown in Figure 1 of the specification, includes a laser, downlink vector signal, electrical local oscillator signal, downlink interference signal, target signal, reference signal, 90° electrical coupler, dual-polarization quadrature phase-shift keying modulator, phase modulator, single-mode fiber, optical coupler, polarization beamsplitter, polarization beam combiner, polarization controller, polarizer, and photodetector. The remote unit (RU) uses a single phase (PM) modulator to achieve self-interference cancellation (SIC) combined with anti-fiber dispersion transmission and down-conversion, eliminating the need for bias control and additional local oscillator (LO) branches, resulting in a simple structure. At the central office (CO), the carried downlink signal and local oscillator signal are single-sideband modulated to achieve anti-fiber dispersion transmission. The RU uses wavelength reuse technology to perform PM cascaded down-conversion on the signal received from the uplink, and the SIC is moved from the RU to the CO to simplify the RU. The entire link has no optical filter and is reconfigurable.

The invention provides a calcium ion concentration detection sensor based on a hydrogel-coated tilted fiber bragg grating and a preparation method of the calcium ion concentration detection sensor. The sensor is composed of a broadband light source, a polarization controller, a TFBG sensor and a spectrum analyzer. The broadband light source is used for providing a light source, the polarization controller is used for obtaining the P polarization state of input light, the hydrogel functionalized TFBG sensor is used for detecting the concentration of a calcium ion solution in the flow cell, the spectrometer is used for monitoring and recording the spectrum change condition, and the solution concentration is obtained according to the transmission spectrum intensity change condition. The device has the advantages of high sensitivity, wide detection range, low detection limit, reusability, electromagnetic interference resistance and small size.

This invention proposes a random microwave pulse generation system and method based on an optoelectronic oscillator, belonging to the field of microwave photonic signal generation and processing technology. The system includes a laser, a polarization controller, a closed-loop optoelectronic oscillator (OEO) loop, a random fiber grating string, and a function generator; wherein the closed-loop optoelectronic oscillator (OEO) loop mainly consists of a Mach-Zehnder modulator, a circulator, an erbium-doped fiber amplifier, a photodetector, an electrical amplifier, and a directional coupler.

The embodiment of the application provides a kind of arrayed microcavity blood pressure detection system based on digital light frequency double comb, it is related to optical sensing technical field.The input end of light intensity modulator is connected with laser, waveform generator respectively, the output end of light intensity modulator, polarization controller, on-chip optical microcavity array are sequentially connected;Light intensity modulator is modulated based on electrical modulation signal to single-frequency light, and optical frequency double comb signal is obtained;Optical frequency double comb signal enters on-chip optical microcavity array after polarization controller, on-chip optical microcavity array is pasted to the position of the artery to be measured, and on-chip optical microcavity array includes multiple sensing units, each sensing unit generates an independent pulse signal, and on-chip optical microcavity array obtains sensing signal based on optical frequency double comb signal and the jump extrusion of the artery to be measured position, and signal processing mechanism obtains blood pressure value information based on sensing signal.The detection system can realize the technical effect of improving the accuracy and convenience of blood pressure measurement.

The application relates to a method of an electric field sensor based on an optoelectronic oscillator, belonging to the field of optical devices and optical fiber sensing. The device comprises a laser source, a polarization controller, a phase modulator, a fiber Bragg grating with an acrylate glue cavity, a stacked piezoelectric ceramic, an electric field generator, an erbium-doped fiber amplifier, a photodetector, a power divider and an electric amplifier. The stacked piezoelectric ceramic is combined with the fiber Bragg grating with the acrylate glue cavity as a sensing head, the wavelength change of the fiber Bragg grating with the acrylate glue cavity caused by the piezoelectric effect is mapped to the frequency change of the microwave signal generated by the optoelectronic oscillator, and the electric field change value can be obtained by monitoring the microwave signal of the optoelectronic oscillator. In the loop of the optoelectronic oscillator, the electric spectrum analysis technology is used for demodulation, and high-speed and high-resolution electric field measurement can be obtained. The method has the advantages of simple structure, high measurement sensitivity and easy practicability.

The application discloses a dynamic polarization controller based on a silicon-based optoelectronic chip, which can lock an arbitrary polarization state light field to an arbitrary required polarization state light field. The controller couples the light of the arbitrary polarization state light field from a single-mode optical fiber into the chip through a first end face coupling structure via a first high numerical aperture optical fiber; after passing through a first polarization rotation beam splitter (PRS), the TE0 mode and TM0 mode light fields entering the chip are both converted into TE0 mode light fields; after polarization locking by adopting a waveguide 0° / 45° / 0° structure, the two TE0 mode light fields are combined into one by a second polarization rotation beam splitter and are converted into TE0 mode and TM0 mode light fields, and then are output to a second high numerical aperture optical fiber via a second end face coupling structure and are relayed into a single-mode optical fiber. The waveguide 0° / 45° / 0° structure adopts an electrically controlled phase shifter, and combines an analog annealing algorithm, a gradient algorithm and other algorithms to automatically lock the polarization state of the light.

This invention discloses a wavelength-tunable dual-cavity ultrafast fiber laser based on rotating optical fibers and its control method, relating to the field of laser technology. The dual-cavity ultrafast fiber laser of this invention integrates a wavelength division multiplexer within a dual-ring resonant cavity, structurally integrating two wavelength channels, each containing an independent gain fiber, to achieve dual-color soliton output and reduce gain competition. By setting an adjustable rotating fiber filter, consisting of a polarization controller, rotating optical fibers, and a polarization-dependent isolator, in the multiplexing section, the center wavelength of both wavelengths is tunable. Simultaneously, the two sub-cavities share the same saturable absorber to achieve passive synchronous mode-locking, and a delay line is introduced into one of the channels to adjust the equivalent cavity length, achieving repetition frequency matching and timing alignment between the two sub-cavities, thereby obtaining stable, tunable, and synchronous dual-wavelength ultrashort pulse output.

The invention discloses a polarization adjusting device and a polarization adjusting method. The polarization adjusting device comprises a light source assembly, a micro-ring resonant cavity, a photoelectric detector, a digital oscilloscope, an arbitrary waveform generator and a power meter module. The light source assembly comprises a light source, a scanning module and a polarization controller connected with the transmission end of the light source. The micro-ring resonant cavity comprises a first output part and a coupling part coupled with the polarization controller. The photoelectric detector is connected with the first output part. The digital oscilloscope comprises a first input part and a second input part used for receiving an electric signal output by the photoelectric detector, and the digital oscilloscope can display the trough of the Lorentz curve. The arbitrary waveform generator includes a second output portion and a third output portion. The second output part is connected with the light source. The third output part is connected with the first input part. The power meter module is connected with the scanning module. According to the polarization adjusting device and the polarization adjusting method, the light source assembly can be quickly and efficiently adjusted to be in the TE polarization state or the TM polarization state.

The application discloses a microwave generation method and device, a microwave generator and a storage medium. The method comprises the following steps: acquiring an optical signal output by an adjustable laser and inputting the optical signal to a preset modulator through a polarization controller; loading a driving signal on the preset modulator and adjusting the power size, and outputting first positive and negative second-order sidebands and second positive and negative second-order sidebands; inputting the first positive and negative second-order sidebands and the second positive and negative second-order sidebands into a polarization maintaining Bragg grating through a circulator, making the sidebands orthogonal to each other through a band-stop filter, and obtaining the first positive and negative second-order sidebands and the second positive and negative second-order sidebands after the orthogonalization; respectively performing modulation processing on the sidebands after the orthogonalization, and obtaining a target signal; and performing spread spectrum on the target signal, and generating a microwave signal. The application acquires two pairs of sidebands through an optical signal and performs modulation, generates a microwave signal after spread spectrum on the target signal obtained, solves the problem of a small adjustable frequency range, and generates an arbitrary waveform phase microwave signal with a large adjustable frequency range and low noise.

This invention belongs to the field of laser pulse polarization control technology, and discloses a high-intensity laser pulse polarization state control system and method. The system includes a laser, a polarization controller, a processing device, and a central control unit. The laser generates and outputs laser pulses; the polarization controller receives the laser pulses emitted by the laser and rapidly adjusts their polarization direction; the processing device applies the polarization-adjusted laser pulses to the processing material; and the central control unit is electrically connected to the laser, polarization controller, and processing device to achieve synchronous control of these components. This invention, employing the aforementioned high-intensity laser pulse polarization state control system and method, achieves a technological breakthrough in ultra-intense laser polarization control through the innovative application of plasma media, possessing high tolerance, high precision, and adaptability, filling a technological gap in this field.

The invention provides a 2-micron all-fiber noise-like space-time mode-locked laser generation and control device and method. The 2-micron all-fiber noise-like space-time mode-locked laser generation and control device comprises a laser generation subsystem and a device regulation and control and image feedback subsystem. Wherein the laser generation subsystem is used for generating a laser pulse with a high-order transverse mode and realizing noise-like space-time mode locking; and the device regulation and image feedback subsystem is used for controlling the output power and temperature of a pumping source, regulating an electronic polarization controller, reading light spot image data through a CCD (Charge Coupled Device) camera to form a closed-loop feedback loop, and realizing state self-recognition and fault self-repair of space-time mode locking through a computer intelligent algorithm. The method has the advantages of being high in practicability, simple in equipment, easy to operate and the like, and stable output of the 2-micron noise-like space-time mode-locked laser is achieved only through a CCD image feedback means without other detection equipment such as an oscilloscope and a spectrograph.

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 application discloses a Fourier domain mode locked laser based on a laser dynamic establishment process and a control method, and comprises a ring laser cavity which is composed of an optical amplifier, a first isolator, a second isolator, an adjustable filter, a delay optical fiber, a coupler and a polarization controller or an optical amplifier, a first isolator, a second isolator, an adjustable filter, a delay optical fiber, a coupler, an intensity modulator and a polarization controller. When the dispersion amount in the ring laser cavity exceeds the bandwidth range of the adjustable filter, the optical amplifier or the intensity modulator is controlled to restart, so that the laser signal is restarted instead of the signal in the continuous gain cavity, the residual dispersion in the cavity is resisted, high coherent swept laser output is realized, any dispersion compensation technology is not needed, the scheme is simple, the requirements of the devices used for the laser are low, environment control technology is not needed, the scheme has strong robustness, the cost is reduced, and the Fourier domain mode locked laser can be applied to any waveband.

The invention relates to the technical field of power transmission line monitoring, in particular to a lightning stroke detection method and device for a self-adaptive polarization controller. According to the invention, the polarization state of the input optical signal is compensated in real time through the self-adaptive polarization controller existing at the receiving and transmitting end of the optical cable line, and the phase shift amount change signal of each phase shifter in the self-adaptive polarization controller is subjected to high-pass filtering processing, so that the occurrence of the lightning stroke event is judged. A timestamp related to occurrence of a lightning stroke event is obtained, and the occurrence position of the lightning stroke event is obtained according to the timestamp. According to the invention, an original framework of an original communication system is not changed, a device does not need to be reset for lightning stroke point positioning, and accurate positioning of a lightning stroke event can be realized while polarization compensation is realized, so that re-laying of a lightning stroke positioning device is avoided, multiplexing of equipment is realized, and application cost is greatly reduced.