469 results about "Polarization controller" patented technology

The invention discloses an optical frequency comb generation method and device based on Brillouin scattering and an electro-optical modulator, and belongs to the field of photoelectric measurement. The method comprises the steps that a first laser and a second laser are used for generating pump light and seed light respectively, multi-wavelength pump light is generated through a cascade electro-optical modulator, the pump light and the seed light are emitted into a Sagnac loop, an optical frequency comb is output through the forward Brillouin scattering effect of an optical fiber and the electro-optical modulator, and the seed light and the pump light are output. The polarization controller is adjusted to optimize polarization state matching of the pump light and the seed light, so that the Brillouin scattering effect reaches the maximum value. The device is composed of a laser, an electro-optical modulator, a signal generator, an optical amplifier, an optical isolator, an optical coupler, a polarization controller and an optical fiber. The optical fiber forward Brillouin scattering effect and the electro-optical modulator are combined, the optical frequency comb giving consideration to the wide frequency spectrum and the narrow interval is generated, meanwhile, the comb tooth interval of the optical frequency comb can be accurately controlled by independently adjusting the frequency of the signal generator, and accurate measurement of signals or objects is achieved.

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 guided-mode resonance refractive index detection device and method based on a longitudinal gradient grating structure, and belongs to the technical field of optical sensing and imaging spectrum detection, the guided-mode resonance refractive index detection device comprises a light source, an optical isolator, a polarization controller, a collimation beam expander, a guided-mode resonance sensing chip, an image detector and a signal processing unit which are connected in sequence; the guided-mode resonance sensing chip is of a transmission type structure, the top of the guided-mode resonance sensing chip is provided with a strip-shaped nano structure which is consistent in period but longitudinally gradually changed, and an image detector is arranged below the guided-mode resonance sensing chip and used for receiving a transmission light signal penetrating through the guided-mode resonance sensing chip, generating a transmission light image and transmitting the transmission light image to the signal processing unit; and the signal processing unit is used for analyzing the transmitted light image and inverting the refractive index of the medium to be measured according to the structure mapping model. According to the invention, the longitudinal structure gradual change characteristic is introduced into the guided-mode resonance chip, so that the spatial distribution control of the monochromatic light resonance response position is realized, and finally the imaging refractive index sensing without an optical splitter 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 light field regulation and control system and method based on laser array coherent combination. A laser array generation module is used for outputting a high-power array light beam; a spatial beam-shrinking light path in the light field regulation and control module samples an array light beam and carries out beam-shrinking processing, so that the light field area of the array light beam after beam-shrinking can be matched with the effective target surface size of spatial light modulators, and the two spatial light modulators respectively regulate and control the phase and polarization of two cross-polarization components of the array light beam after beam-shrinking. The regulated light beam is transmitted to a phase and polarization locking loop; and the phase and polarization locking loop generates a phase control signal and a polarization control signal according to the regulated light beam output by the light field regulation module, and applies the phase control signal and the polarization control signal to a phase modulator and a polarization controller of each path of unit laser in the laser array generation module, so that phase and polarization locking of the high-power array light beam is realized. According to the invention, flexible light field regulation and control of far-field synthetic light spots of the array light beams can be realized.

The utility model discloses a distributed sound wave sensing system for multi-frequency pulse modulation, and relates to the technical field of distributed sound wave sensing. The system comprises a narrow linewidth laser, an optical fiber coupler, a polarization-maintaining optical isolator, an acousto-optic modulator, a polarization-maintaining delay optical fiber, an erbium-doped optical fiber amplifier, a polarization-maintaining dense wavelength division multiplexer, an optical fiber circulator, an optical fiber Bragg grating, a piezoelectric transducer, a polarization controller, a photoelectric balance detector, a data acquisition card, an arbitrary waveform generator and the like. According to the utility model, the multi-frequency delay ring is utilized to carry out multi-frequency modulation, the frequency number of light waves is increased along with the circulation times of the light waves in the delay ring, and under the condition that the utilization of a large-bandwidth electro-optical modulator is not increased, the flexible modulation of the frequency is realized by utilizing a low-bandwidth acousto-optical modulator without being influenced by carrier frequency and sidebands of each order; the low-bandwidth acousto-optic modulator is used for frequency modulation in the multi-frequency delay ring, and compared with an electro-optical modulation or multi-acousto-optic / multi-light source modulation scheme, the modulation cost is effectively saved.

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 dual-wavelength mode-locked laser generating device and a dual-wavelength mode-locked laser generating method, and belongs to the technical field of optical communication, and the dual-wavelength mode-locked laser generating device comprises a pumping source, an optical integration module, a gain optical fiber, a saturable absorber and a dual-wavelength pulse independent polarization mode linear coupling regulation and control structure, linear coupling strength of cross-polarization components in two wavelength pulses is independently regulated and controlled by using a structure of a polarization controller and a polarization maintaining optical fiber, and dual-wavelength mode-locked pulse laser of different types of pulse combinations can be obtained. The coherent pulse light source with unique spectral characteristics can provide a low-cost light source for the fields of high repetition frequency optical combs, all-fiber architecture high repetition frequency soliton sequences and microwave photonics.

The invention relates to a sweep frequency optical frequency comb generation system and a generation method. Fourier mode locking is realized through a Fourier mode locking photoelectric oscillator system. The sweep frequency optical frequency comb generation system is a closed Fourier mode-locked laser loop which is composed of a first optical amplifier, an optical fiber isolator, a broadband filter, a polarization controller, a thin film lithium niobate optical chip, a signal generator, a dispersion compensation optical fiber and a first optical coupler; and a photoelectric oscillator loop is formed by a second optical coupler, a single-mode delay optical fiber, a second optical amplifier, a photoelectric detector, a narrow-band filter, a low-noise amplifier and an electric power divider. Time domain active mode locking and Fourier mode locking are carried out on the laser resonant cavity at the same time, synchronous modulation of multiple optical frequency comb modes is achieved, sweep frequency optical frequency comb signals with high repetition frequency, high modulation speed, high coherence length and high output power are generated, and tunable optical frequency comb and high-quality high-frequency microwave signal output can be provided at the same time.

The invention discloses a system for simultaneously measuring temperature and pressure based on forward Brillouin scattering in a multi-core optical fiber, which relates to the technical field of optical fiber temperature and pressure double-parameter sensors, and is characterized in that light emitted by a pump light source enters a polarization controller after being modulated by a pump light modulation system, and then enters an erbium-doped optical fiber amplifier; one part is injected into a Sagnac ring, and the other part excites a high-order torsion-radial mode through a multi-core optical fiber; light emitted by the detection light source is divided into light beams transmitted in the clockwise direction and the anticlockwise direction through the coupler, and the light beams are injected into the Sagnac ring; the spectrum analyzer captures the frequency shift of the Brillouin scattering signal; the signal processing unit processes the frequency shift of the Brillouin scattering signal and inverts temperature and strain data; and the data analysis and feedback system is combined with machine learning to optimize temperature and strain data. According to the invention, high-sensitivity temperature and strain sensing is realized.

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 a 2-micron-waveband adjustable all-fiber high-repetition-frequency pulse light source generator, belongs to the technical field of laser light source manufacturing, and aims to solve the problem that an existing 2-micron-waveband passive all-fiber mode-locked pulse laser light source is difficult to give consideration to fs-magnitude narrow pulse width and ultra-short-cavity-length high-fundamental-frequency repetition frequency output. The laser comprises a semiconductor laser pumping source, a wavelength division multiplexer, an extrusion type polarization controller I, a polarization-maintaining highly-doped gain fiber, an extrusion type polarization controller II, a long cone region tapering micro-nano fiber, a 2 * 2 fiber coupler and a fiber Faraday mirror. According to the invention, the long-cone micro-nanofiber is introduced into the cavity, and the long-cone micro-nanofiber has the characteristic of high nonlinear coefficient, so that the cavity length can be greatly shortened, enough nonlinear phase shift can be accumulated, and fs-magnitude ultrashort pulse can be output. The device is low in loss, stable in performance and easy to integrate with other optical fiber systems. The laser can be applied to the fields of optical communication, non-metallic material processing, laser medical treatment, intermediate infrared laser pumping sources and the like.

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 relates to a nanosecond fiber laser and method for high-order chaotic pulses. A fiber ring cavity of the laser comprises a wavelength division multiplexer, an erbium-doped fiber, a first polarization controller, an analyzer, a second polarization controller, an output coupler, a dispersion control unit, a fiber isolator and a band-pass filter which are connected in sequence. The method comprises the steps that pumping continuous light is coupled into the laser through the wavelength division multiplexer; pumping continuous light is absorbed by using an erbium-doped optical fiber and is stimulated to radiate a long-wave-band gain pulse; under the combined action of the first polarization controller, the polarization analyzer and the second polarization controller, an equivalent saturable absorption effect is generated by utilizing nonlinear polarization rotation generated when gain pulses are propagated in an optical fiber, and large anomalous dispersion is introduced to realize generation of nanosecond pulses; through the band-pass filter, nanosecond pulses are allowed to be generated, and meanwhile, the nonlinear increasing speed of propagation and accumulation of the nanosecond pulses in the cavity is controlled, so that order-by-order generation of high-order chaotic pulses is realized. According to the invention, reliable output of high-order chaotic pulses can be realized.

The invention belongs to the technical field of optical communication testing, and provides a multichannel synchronous optical wavelength scanning test module and a data fusion system thereof, the multichannel synchronous optical wavelength scanning test module comprises a scanning light source, a multichannel scanning optical power meter, a wavelength analysis unit, a polarization controller, a trigger synchronization unit and an integrated platform; the scanning light source is configured to provide a basic light source; the multi-channel scanning optical power meter is configured to measure optical power of a plurality of channels at the same time to obtain optical power data; the wavelength analysis unit is configured to perform wavelength analysis on the optical signal output by the basic light source so as to determine the wavelength value of the optical signal; the trigger synchronization unit is configured to realize linkage control between the scanning light source and the polarization controller to form polarization state-wavelength cooperative scanning so as to synchronously complete wavelength scanning and switching of multiple polarization states; the integrated platform is configured to perform unified control and management; according to the invention, high-precision and high-efficiency multichannel optical wavelength scanning test can be realized.

The invention discloses a multi-path polarization phase active control system and method of a sub-aperture coherent synthesis system, and relates to the technical field of sub-aperture coherent synthesis, the system comprises a detection module and a control module, the detection module samples coherent synthesis light, synthesizes and detects sampled light and reference light, and controls the control module to control the coherent synthesis light. A first detection signal and a second detection signal are obtained, the control system demodulates the first detection signal to obtain a phase error signal corresponding to each beam splitting light, and each phase modulator is controlled to work based on the phase error signal corresponding to each beam splitting light so as to adjust the phase of each beam splitting light. And demodulating the second detection signal to obtain a polarization error signal corresponding to each beam splitting light, and respectively controlling each polarization controller to work based on the polarization error signal corresponding to each beam splitting light so as to adjust the polarization of each beam splitting light. According to the invention, multi-path polarization phase active control with high control speed can be realized under the condition of low system complexity.

The invention discloses an optical time domain reflectometer based on ring structure modulation and a working method thereof, and relates to the technical field of optics. The optical time domain reflectometer comprises a laser, an optical fiber coupler, a semiconductor optical amplifier, an acoustic optical modulator, an optical isolator, a delay optical fiber, an erbium-doped optical fiber amplifier, a dense wavelength division multiplexer, a circulator, a Raman laser, piezoelectric ceramics, an arbitrary function generator, an arbitrary waveform generator, a polarization controller, a photoelectric balance detector, a data acquisition card, a computer and the like. Multi-frequency modulation is carried out based on an annular structure, the multi-frequency modulation range is only limited by the bandwidth of a detector and the sampling rate of an acquisition card, a pulse sequence is generated through modulation of the optical annular structure, dependence on the bandwidth performance of a microwave signal source and a modulator is reduced, and the bandwidth is improved; and by injecting the Raman light, the sensing distance is also increased, the equipment cost is effectively controlled, and meanwhile, a new scheme is provided for time sequence pulse sequence modulation.

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.

The embodiment of the invention provides an on-chip polarization controller and a chip, relates to the technical field of photon integration, and aims to solve the problem of relatively high insertion loss. The on-chip polarization controller comprises an input end device, a first connecting device and an output end device, the input end device comprises a first adjustable wave plate and a first polarization beam splitting rotator, and the first adjustable wave plate is used for receiving the first signal light and adjusting the phase difference between first polarized light and second polarized light in the first signal light. The first polarization beam splitting rotator is used for receiving first signal light output by the first adjustable wave plate; the second signal light and the third signal light are both in a horizontal polarization state. The second signal light and the third signal light are formed by converting part of the first polarized light and part of the second polarized light. The first connecting device is used for adjusting the relative phase between the second signal light and the third signal light; and the output end device is used for coupling and outputting the second signal light and the third signal light. The on-chip polarization controller can be applied to a photon chip.

An optical module includes an optical connector port, a plurality of variable optical attenuators, a first polarization controller, and an output port. The optical connector port connects to an optical port on a line card and receives a plurality of input optical signals from the line card when the optical connector port is connected to the optical port on the line card. The plurality of variable optical attenuators produce a plurality of attenuated optical signals based on the plurality of input optical signals. The first polarization controller produces a plurality of output optical signals based on the plurality of attenuated optical signals. The output port outputs the plurality of output optical signals.

The utility model discloses an angle fine adjustment type multi-ring polarization controller, which belongs to the technical field of polarization controllers and comprises a base and an embedded polaroid element, and an optical fiber is embedded in the embedded polaroid element. The bottom of the base is fixedly provided with a high-precision angle-adjusting schematic assembly, the high-precision angle-adjusting schematic assembly comprises a main shell, a driven gear is rotationally installed in the main shell through a second shaft body, the bottom of the embedded polaroid element is fixedly provided with a driving gear, and the driving gear and the driven gear are in mutual meshing transmission; an angle sensor is concentrically positioned in the driven gear, and a vector sensor, a battery and a display screen which are distributed on the front side and the rear side of the driven gear are further installed in the main shell. When the polarization controller adjusts the angle of the embedded polaroid element, the deflection angle can be displayed in real time through the display screen, the deflection angle is accurately measured through the angle sensor, and the polarization controller is more accurate when adjusting the angle of the embedded polaroid element.

The present invention discloses a large dynamic range resonant fiber optic gyroscope, belonging to the technical field of optical sensing. It solves the problem that current optical gyroscopes have a small dynamic range and are non-adjustable, making it difficult to meet the needs of places with a large range of rotational speed variations, and that the direction of rotational speed can only be determined by phase modulation of light. The invention comprises first and second voltage signal sources, a laser, a polarization controller, a fiber coupler, a fiber ring, a piezoelectric ceramic tube, a detector, and a signal processing and control system. The invention utilizes the piezoelectric ceramic tube to control the cavity length of the fiber resonant cavity, thereby achieving a large dynamic range. At the same time, a narrow linewidth laser is utilized to output continuous, constant-intensity, frequency-tunable narrow linewidth laser light to obtain the transmission spectrum of the fiber resonant cavity. By accurately locating the resonant frequency, the magnitude and direction of the rotational speed can be simultaneously determined. The invention has the advantages of a large dynamic range, a large rotation rate measurement range, and the ability to determine the direction of rotational speed without phase modulation of light.

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 invention provides a signal detection system and method based on an echo wall mode microcavity, and can be applied to the technical field of signal detection. The system comprises a wide-spectrum light source used for outputting wide-spectrum light; the polarization controller is used for modulating the wide-spectrum light to obtain polarization modulated light; the echo wall mode microcavity sensor is used for exciting a plurality of resonance modes under the action of the polarization modulation light and outputting detection light corresponding to the plurality of resonance modes under the action of the target slow change signal; the spectrograph is used for detecting the detection light to obtain a plurality of light frequency amplitudes corresponding to the plurality of resonance modes respectively; the processor is used for generating a bar code according to the plurality of optical frequency amplitudes; determining a target bar code matched with the bar code from a plurality of predetermined bar codes included in a bar code database; and determining the size of the target slow change signal according to the target bar code.

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.