552 results about "Polarization controller" patented technology

The invention belongs to the technical field of retina imaging and fundus three-dimensional reconstruction, and particularly relates to a color three-dimensional fundus imager optical system. Comprising a large eye objective lens, a dichroscope, a hollow reflector, a focusing lens, a spectroscope, a retina lens, a retina imaging chip, a fixation lens, a sighting mark lamp, an illumination lens, an annular light source, a pupil lens, a pupil imaging chip, an infrared lens, an infrared dodging lens, an infrared light source, a scanning lens, a three-dimensional galvanometer, a collimator, a coupler, a frequency sweeping light source and a dispersion compensator. A polarization controller, a coupler and a photoelectric detector. The system is mainly composed of a visible light imaging light path, an infrared imaging light path and a laser imaging light path, the visible light imaging light path is used for shooting color fundus two-dimensional images, the infrared imaging light path is used for real-time positioning and focusing of human eye pupils, and the laser imaging light path is used for three-dimensional tomography of retinas. The objective of the invention is to solve the problem that existing medical equipment cannot acquire fundus color three-dimensional images.

The invention discloses a range gating anti-disturbance optical frequency domain reflection distributed measurement device and method. The device comprises a sweep frequency laser light source, a first optical coupler, a Mach-Zehnder modulator, a circulator, a detection optical fiber, a polarization controller, a second optical coupler, a balanced photoelectric detector and a data measurement unit. Wherein the Mach-Zehnder modulator is configured to perform BPSK modulation on the input probe light by using a pseudo-random spread spectrum coding technology. By means of the device and the method, the contradiction that long-distance measurement and fast frequency sweeping are difficult to achieve at the same time in a traditional OFDR is successfully solved.

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 an optical acoustic sensor, in particular to a high-sensitivity acoustic sensor based on Fano resonance and a measuring method. The problem that an existing optical acoustic sensor is low in sensitivity is solved. A high-sensitivity acoustic sensor based on Fano resonance comprises a 1550nm laser, a phase modulator, a first polarization controller, a conical optical fiber, a CaF2 crystal resonant cavity, a second polarization controller, a photoelectric detector, an oscilloscope and a computer. The emergent end of the 1550nm laser is connected with the head end of the conical optical fiber through the phase modulator and the first polarization controller in sequence; the conical optical fiber is coupled with the CaF2 crystal resonant cavity; the tail end of the conical optical fiber is connected with the incident end of the photoelectric detector through the second polarization controller; the signal output end of the photoelectric detector is connected with the signal input end of the oscilloscope; the signal output end of the oscilloscope is connected with the signal input end of the computer. The method is suitable for acoustic signal measurement in the fields of industry, traffic, environmental protection, medical treatment and the like.

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 relates to the technical field of optical fiber sensing, in particular to an optical fiber sensor system, a sensing signal measuring method, computer equipment and a medium. The optical fiber coupler comprises at least two optical fiber interference arms which are arranged in parallel and is used for dividing an optical signal into at least two beams and enabling the beams to be propagated along different paths to generate interference; the polarization controller is arranged at the emergent end of the optical fiber coupler and is used for regulating and controlling the polarization state and the polarization direction of the emergent light; the voltage control module is arranged on at least one optical fiber interference arm and used for changing the phase of the optical fiber by applying voltage; the image sensor is used for collecting interference fringe images and converting the interference fringe images into electric signals; and the data processing device is used for carrying out peak searching calculation on the electric signal to obtain stripe movement information, and obtaining a corresponding sensing signal value according to the relationship between the stripe movement information and the sensing signal. The application range of the interferometer in the visible light wave band is expanded, and the measurement precision of the interferometer is improved.

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 invention belongs to the technical field of lasers, and discloses a fiber laser for promoting generation of a stable soliton attraction state by using a high-birefringence fiber. The optical fiber laser comprises a laser pumping source, a wavelength division multiplexer, an erbium-doped gain optical fiber, a polarization independent isolator, a polarization controller, a polarization maintaining optical fiber, an output coupler and a mode locking device based on a carbon nanotube saturable absorber, and all the components are sequentially connected through single-mode optical fibers. The polarization-maintaining optical fiber is a panda-shaped polarization-maintaining optical fiber with a high birefringence effect. The polarization direction and the polarization state in the cavity are accurately controlled by adjusting the polarization controller, phase synchronization of soliton pulses is achieved when the polarization maintaining optical fiber is output, soliton energy in the cavity is rapidly accumulated, soliton splitting is triggered, and finally a stable multi-pulse soliton attraction state is formed. The design is simple and convenient to operate, and stability and anti-interference capability of soliton transmission are remarkably improved.

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 periodic forked near-transformation limit nanosecond pulse mode-locked fiber laser and a generation method. The laser is characterized in that a fiber ring cavity comprises a wavelength division multiplexer, an erbium-doped fiber, a first polarization controller, a polarization analyzer, a dispersion control unit, an output coupler, a fiber isolator and a second polarization controller which are sequentially connected in a closed loop mode. 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 fiber and is stimulated to radiate a gain pulse with a long wave band, and the generated pulse oscillates in a fiber laser cavity; under the combined action of a first polarization controller, an analyzer and a second polarization controller, an equivalent saturated absorption effect is generated by utilizing nonlinear polarization rotation generated when gain pulses are propagated in an optical fiber, and pulse mode locking is realized; the optical fiber laser works in an abnormal dispersion region, so that generated pulses meet the soliton area theorem, and near-transformation limit pulses are generated. According to the invention, nanosecond pulse period bifurcation output of the short-cavity fiber laser can be realized.

The invention discloses a multi-parameter parallel detection method based on a single whispering gallery optical microcavity, which belongs to the field of whispering gallery microcavities; the method comprises: the two ends of an optical polarization controller are respectively connected to a laser and a whispering gallery microcavity sensor, the whispering gallery microcavity sensor is connected to multiple target parameter information disturbance devices, and a photodetector; the laser outputs an optical signal, which is adjusted to the maximum coupling efficiency by the optical polarization controller and then output to the whispering gallery microcavity sensor, and the target parameter information disturbance device is adjusted to disturb the optical signal by the target parameter, and the disturbed optical signal is output to an oscilloscope through the photodetector, which is reflected as n resonance mode offsets, and the changes of n target parameters are calculated by a signal processing method combining n offsets with an n-order sensor matrix, thereby realizing the multi-parameter parallel detection of the whispering gallery optical microcavity. The invention can realize high-precision decoupling and parallel detection of multiple parameters.

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 provides a reference light polarization multiplexing TF-QKD device and a coding method, and relates to the technical field of quantum communication. A light source emitted by a single-wavelength laser is subjected to time division multiplexing modulation through a phase modulator, an intensity modulator and a polarization modulator to obtain a strong phase reference light pulse, a weak phase reference light pulse and a quantum signal light pulse; after being attenuated by the optical attenuator, the signals are sent to a detection end through an optical fiber line; after light pulses of an Alice end and a Bob end received by a detection end pass through respective links, the light pulses are modulated by polarization controllers of respective light paths and then enter a light interference module for interference, the interfered light is divided into two beams, and the two beams respectively enter a first polarization beam splitter and a second polarization beam splitter for polarization; the light split by each polarization beam splitter respectively enters two avalanche detectors for detection, and the detection result is sent to a synchronous counter to ensure that the pulse arrival time of the Alice end is consistent with the pulse arrival time of the Bob end.

The invention provides an all-fiber ultrafast laser based on 1.7 micron high energy. The all-fiber ultrafast laser comprises a pumping source, a wavelength division multiplexer, a gain fiber, a band-pass filter, an output coupler, a single-mode fiber, a first three-ring polarization controller, a polarization dependent isolator and a second three-ring polarization controller. The output end of the pumping source is connected with the wavelength division multiplexer, the output end of the wavelength division multiplexer is connected with the band-pass filter through the gain fiber, the output end of the band-pass filter is connected with the output coupler, and the first output port of the output coupler is connected with the input end of the first three-ring polarization controller through the single-mode fiber. A second output port of the output coupler is used as the output of the all-fiber ultrafast laser, the output end of the first three-ring polarization controller is connected with the polarization dependent isolator, the output end of the polarization dependent isolator is connected with the second three-ring polarization controller, and the output end of the second three-ring polarization controller is connected with the wavelength division multiplexer.

A system and method for locking laser frequency based on a hollow fiber FP resonant cavity are characterized in that the output end of a laser is connected with the first port of an optical fiber circulator, the second port of the optical fiber circulator is connected with the input end of an optical fiber coupler, and the first output end of the optical fiber coupler is connected with the input end of a polarization controller; a second output end of the optical fiber coupler is connected with an input end of the optical trap, an output end of the polarization controller is connected with an input end of the hollow-core optical fiber Fabry-Perot resonant cavity, and an output end of the hollow-core optical fiber Fabry-Perot resonant cavity is connected with a third port of the optical fiber circulator; the second output end of the optical fiber coupler is connected with the input end of the optical trap, the second output end of the optical fiber coupler is aligned with the input end of the optical trap, and optical signals output by the second output end of the optical fiber coupler directly enter the optical trap. The system is simple in structure, low in implementation cost, wide in locking range, high in anti-interference capability and high in integration degree.

The invention relates to an on-chip integrated phase coding microwave signal generation system and method. The system comprises a laser, a polarization controller, a first chip end face coupler, a thin film lithium niobate optical chip, a second chip end face coupler, a signal generator, an optical fiber amplifier, an optical fiber isolator, a photoelectric detector and a microwave source. According to the invention, a first-order sideband of a phase modulation optical signal generated by the phase modulator is suppressed through filtering of the electrically tunable micro-ring resonator in the thin-film lithium niobate optical chip. The signal generator applies a periodically coded voltage signal to the electrically tunable micro-ring resonator, the position of a micro-ring harmonic peak is periodically controlled, and high and low levels of the voltage control signal correspond to the distance between two adjacent harmonic peaks of the electrically tunable micro-ring resonator and positive and negative first-order sidebands of the phase modulation optical signal. According to the invention, high-frequency and frequency-adjustable phase-coded microwave signals can be generated, and the system has the advantages of small voltage tuning range, flexible coding and simple system structure.

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 broadband spectrum all-fiber femtosecond laser system based on chirped pulse amplification and an adjusting method of the broadband spectrum all-fiber femtosecond laser system. The broadband spectrum all-fiber femtosecond laser system comprises a broadband spectrum dissipative soliton mode-locked fiber laser and an all-fiber chirped pulse amplifier which are connected. The broadband spectrum dissipative soliton mode-locked fiber laser comprises a first pumping source, a first wavelength division multiplexer, a first gain fiber, a first polarization controller, a polarization dependent isolator, a second polarization controller and a coupler. The all-fiber chirped pulse amplifier comprises a first polarization independent isolator, a dispersion compensation fiber, a second wavelength division multiplexer, a second gain fiber, a third wavelength division multiplexer, a single-mode fiber, a second polarization independent isolator, a second pumping source and a third pumping source. The system realizes the wide spectrum characteristic through the optical fiber length adjusting module, the spectrum adjusting module and the fine adjusting module. The device is simple in structure, wide in application scene, not prone to pulse distortion, wide in spectrum and high in anti-interference capacity.

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 a test method and device for measuring nonlinearity of a phase modulator, and belongs to the technical field of measurement, the device comprises a laser source, a polarization controller, a beam splitter, the phase modulator, a coupler, a photoelectric detector, a microwave source I, an acousto-optic frequency shifter, a microwave amplitude phase detection module and a microwave source II; the laser source is used for outputting a fixed-frequency optical signal to the polarization controller; the polarization controller is used for compensating the polarization state of the optical signal; the beam splitter is used for equally dividing an optical signal into two paths, the first path of optical signal is transmitted to the phase modulator, and the second path of optical signal is transmitted to the acousto-optic frequency shifter; by means of the mode, the problem that the phase modulator directly enters the photoelectric detector, photoelectric conversion cannot be conducted, and nonlinear parameters cannot be detected is solved.

The invention discloses a tilted fiber grating hydrogen sensor based on UiO‑66‑NH2, which is composed of a broadband light source, a polarization controller, a first single-mode optical fiber, a tilted fiber grating, a second single-mode optical fiber, a spectrometer, a gas chamber, a UiO‑66‑NH2 film, a hydrogen gas flow control valve, a nitrogen gas flow control valve, a hydrogen bottle, a nitrogen bottle, and PDMS; wherein the tilted fiber grating is attached with PDMS, and the UiO‑66‑NH2 film is attached through PDMS. The UiO‑66‑NH2 powder prepared by a solvothermal method is uniformly coated on the tilted fiber grating through PDMS as a hydrogen sensitive layer. The invention has the advantages of fast response speed and high sensitivity, and has good practical value and application prospects.

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.