163 results about "Raman laser" patented technology

The invention provides a Raman-meter signal all-day laser radar ratio inversion method and device, and the method comprises the steps: carrying out the denoising of signal data of a Raman laser radar in a preset time period, and carrying out the inversion, and obtaining a first aerosol backscattering coefficient profile; applying a plurality of preset laser radar ratios to the inversion of the meter laser radar signal at the same moment to obtain a plurality of second aerosol backscattering coefficient profiles; taking the first aerosol backscattering coefficient profiles at the same moment as a reference standard, calculating a relative error average value of each second aerosol backscattering coefficient profile, and obtaining an optimal laser radar ratio corresponding to the minimum relative error average value; fitting the optimal laser radar ratio with the mean value of the aerosol depolarization ratio of the meter laser radar below the boundary layer height at the corresponding moment to obtain a relation curve; and substituting the mean value of the aerosol depolarization ratio at the current moment into the relation curve to obtain the laser radar ratio. According to the invention, the inversion precision of the aerosol laser radar ratio is improved.

The invention relates to a terahertz-Raman integrated detection system and method. The detection system comprises a fusion mainframe box and an integrated probe arranged at a sample detection end on the fusion mainframe box, a Raman spectrum module, a terahertz spectrum module, a terahertz optical module and a data analysis module are arranged in the fusion mainframe box; the Raman spectrum module is composed of a Raman laser, a Raman light filter, a Raman grating and a Raman detector which are sequentially connected through a light path; the terahertz spectrum module is composed of a terahertz femtosecond laser, a transmitting photoconductive antenna, a receiving photoconductive antenna and a terahertz detector which are sequentially connected through a light path; the data analysis module is in communication connection with the Raman detector and the terahertz detector and is used for synchronously processing data transmitted by the Raman detector and the terahertz detector. Compared with the prior art, the integrated probe synchronously collects two kinds of spectral data and carries out fusion processing on the two kinds of spectral data through the data analysis module, and the device has the remarkable effects that the device integration degree is high, the detection efficiency and accuracy are greatly improved, and the application range is wide.

The invention discloses a method for measuring a detection inclination angle of a two-component atomic shearing interferometer. The method comprises the following steps: constructing an inclination angle set of an angle swinging device; when the atoms are acted by the pi Raman laser and the second pi / 2 Raman laser, the reflecting mirror rotates by an angle; alternately detecting multiple groups of odd-numbered groups and even-numbered groups; traversing all dip angles in the dip angle set; and fitting and calculating the actual included angle of the longitudinal direction of the imaging surface of the CCD camera relative to the Z-axis direction. The invention further discloses a measuring device for the detection inclination angle of the two-component atom shearing interferometer. According to the method, an existing atom shearing interferometer can accurately measure the inclination angle of a detection system of the atom shearing interferometer, so that the problems of noise and system errors caused by the fact that the inclination angle of the detection system of the atom shearing interferometer does not return to zero are solved, and drifting of differential measurement of the two-component atom interferometer caused by inclination angle changes is restrained.

The invention relates to the technical field of spectral imaging detection, in particular to a spontaneous-stimulated Raman co-localization single-cell substructure atlas analysis system and a spontaneous-stimulated Raman co-localization single-cell substructure atlas analysis method. The system comprises a femtosecond pulse excitation module used for outputting two beams of broadband femtosecond pulse laser with different frequencies and continuously adjustable optical power; the Stokes light modulation module is used for modulating the Stokes light and carrying out space beam combination on the Stokes light and the pump light; the pump light modulation module is used for modulating pump light; the spontaneous Raman laser continuous adjusting module is used for outputting spontaneous Raman laser; the stimulated Raman exciting light co-positioning module is used for combining the combined laser and the spontaneous Raman laser again, focusing the combined laser and the spontaneous Raman laser on a sample, exciting a stimulated Raman scattering signal, converting the stimulated Raman scattering signal into a digital signal and carrying out data acquisition; and the spectrum detection module is used for collecting the spontaneous Raman scattering light which is reflected and returned along the original light path, and collecting a spectrum signal to form a Raman spectrum. The method has the advantage of improving the accuracy of single-cell heterogeneity structure and cancer cell type discrimination.

Various optical systems for use in a light pulse atomic interferometer (LPAI)-based one-, two-, or three-axis accelerometer or gyroscope are disclosed. As an LPAI accelerometer or gyroscope may employ many different laser beams to implement the LPAI functionality, ways of combining these different laser beams to thereby simplify the optical systems are desired. The cooling laser beam portion of the optical system may be simplified using one or more reflective grating chips. The Raman laser beam optics may be simplified using combiners and separators. For LPAI systems sensing along three axes, various optical switching schemes may be employed, including ones that generate variable data-rates with a primary sensing axis having a higher data-rate than the secondary sensing axes. Further, by combining various laser beams in a time-multiplexed manner, the number of optical fiber tethers to a sensor head may be reduced.

The invention belongs to the technical field of atomic inertial measurement, and discloses a continuous measurement atomic interferometer control method and system. The method comprises the steps that atoms are sequentially subjected to N times of stimulated Raman transition, the time difference between the stimulated Raman transition is T, atom interference is achieved, in the same vacuum cavity, a plurality of atomic groups are sequentially subjected to atom interference, when the Kth atomic group is subjected to the nth time of stimulated Raman transition, the (K + 1) th atomic group and the Kth atomic group share Raman laser, and the Kth atomic group and the (K + 1) th atomic group share Raman laser. And the first stimulated Raman transition of the (K + 1) th atomic group is synchronously carried out, so that the atomic interference of the atomic group in the vacuum cavity at each moment can be ensured, the output result of the interferometer covers the working time of the whole interferometer, the continuous measurement of the atomic interferometer is realized, and n is less than or equal to N.

The invention discloses a flow-type Raman sorting method and a high-luminous-flux flow-type Raman sorting device, and the method comprises the following steps: carrying out coincident focusing on Raman laser and near-infrared laser captured by a light trap to form a Raman excitation detection site, and arranging the Raman excitation detection site at the tip of the outer end of a tail end electrode in a chip dielectric focusing electrode; the photo-thermal oscillation near-infrared laser is focused on a tail end electrode in a dielectric focusing electrode of the chip and does not coincide with a Raman excitation detection site; through switching of light trap capture near-infrared laser and photo-thermal oscillation near-infrared laser, a single cell sample is captured and fixed at a Raman excitation detection site through light trap capture force generated by the light trap capture near-infrared laser or bubbles are generated through a photo-thermal effect generated by the photo-thermal oscillation near-infrared laser; the cell sample adhered to the tail end electrode in the dielectric focusing electrode is oscillated and separated through the bubbles. Compared with the prior art, the device has the beneficial effects that the organic combination of optical trap capture and dielectric capture sample oscillation functions can be realized, the switching is convenient, flexible, rapid, simple and reliable in use, the instrument cost is greatly reduced, the application range of the instrument is effectively widened, and the device has very strong universality.

The invention provides a tip Raman-based metal oxide nanoparticle in-situ detection method, which comprises: S1, dispersing metal oxide nanoparticles in a nanoparticle dispersion liquid, focusing laser to the tip of a nanometer tip through an objective lens, capturing a single nanoparticle by using an optical tweezers technology, and attaching the single nanoparticle to the nanometer tip; s2, focusing Raman laser on a nano needle tip-particle interface, generating a local high-temperature field through a photo-thermal near-field coupling effect, triggering a thermal chemical reaction of nano particles, and synchronously collecting a Raman spectrum; and S3, carrying out pretreatment and characteristic peak analysis on the collected Raman signal of the Raman spectrum, and determining the reaction critical temperature and the dynamic process in combination with temperature calibration data. According to the invention, capture and accurate heating of the nanoparticles are realized through photo-thermal coupling of the optical tweezers and the needle tip, and thermal chemical reaction monitoring of the nanoparticles is realized.

The invention provides a holmium and ytterbium co-doped mid-infrared microsphere Raman laser and a preparation method thereof, and relates to the technical field of laser preparation, the holmium and ytterbium co-doped mid-infrared microsphere Raman laser comprises an infrared transmission optical fiber, a pump light source, holmium and ytterbium co-doped tellurate glass microspheres and passive tellurate glass microspheres, pump light emitted by the pump light source is guided to a conical region through the infrared transmission optical fiber, and the holmium and ytterbium co-doped tellurate glass microspheres and the passive tellurate glass microspheres are arranged in the conical region; sequentially carrying out optical coupling with holmium and ytterbium co-doped tellurate glass microspheres and passive tellurate glass microspheres; in the holmium and ytterbium co-doped tellurate glass microspheres, the doping amount of the holmium element is 0.3%, and the doping amount of the ytterbium element is 0.45% according to the mass percentage. Compared with the prior art, through the cascade structure of the holmium-ytterbium co-doped microspheres and the passive microspheres, three-step wavelength conversion of pump light-rare earth ion lasing-Raman frequency shift is realized in a single system for the first time, and the wavelength limitation that a traditional single microsphere depends on a rare earth ion fixed energy level is broken through.

The invention discloses a cloud condensation nucleus number concentration inversion method and device, a medium and a product, and relates to the field of atmospheric environment detection.The method comprises the steps that particulate matter parameters observed by a multi-wavelength polarization Raman laser radar are obtained; the particulate matter parameters comprise a radar ratio, a depolarization ratio and a depolarization color ratio; determining the aerosol type according to the particulate matter parameters; based on the aerosol type, extracting an extinction coefficient and a backscattering coefficient of each aerosol; performing relative humidity correction on the extinction coefficient and the backscattering coefficient, and determining a corrected optical parameter; matching the corrected optical parameters with optical parameters in an aerosol optical parameter database to determine aerosol parameters; calculating the critical radius of each aerosol under different supersaturation ratios; and for each aerosol, according to the critical radius and the aerosol parameter, inverting the CCN number concentration under different supersaturation ratios, and according to the method, the CCN number concentration under different supersaturation ratios can be accurately inverted.

The invention provides a method for nondestructive detection of contents of EPA and DHA in adductor muscles of scallops based on Raman spectroscopy, which comprises the following steps: taking a proper amount of gill filament tissues in a survival state of the scallops by using a nondestructive gill filament tissue taking method, preparing into frozen slices, performing Raman laser scanning on the slices to obtain original data, performing pretreatment such as normalization, noise reduction, baseline correction and the like, and determining the content of EPA and DHA in the adductor muscles of the scallops. Selecting a characteristic wavelength, and combining with adductor muscle lipidome data to establish a model for predicting the content of unsaturated fatty acid in adductor muscle in a cross-tissue manner by gill filament Raman data. Compared with an existing method for detecting the content of unsaturated fatty acid in scallops, the method has the advantages that the content of unsaturated fatty acid in rhabdoids of main edible parts of the scallops can be quickly, accurately and simply detected under the condition that the scallops survive, and the detection cost is greatly reduced; an efficient and simple technical means is provided for breeding of shellfish quality characters, and popularization and promotion in comprehensive evaluation and genetic improvement work of aquatic germplasm are facilitated.

The invention discloses a cold atom interference type low-frequency vibration measurement device and a measurement method, and solves the problems that the existing cold atom interference gravimeter measurement equipment is limited by the performance of a vibration sensor, the compensation precision is insufficient, timing calibration is needed, and the measurement precision is low. And measurement errors generated by gravity and ultralow-frequency vibration cannot be effectively separated from a measurement result of the cold atom interference gravimeter, namely, decoupling of two measurement parameters is realized, and cold atom interference measurement of low-frequency vibration is realized. The measuring device comprises a Raman laser output system, a vacuum cavity, a sensitive axis converter and a vibration detection reflecting mirror, the Raman laser output system outputs two pieces of Raman laser which have the same polarization state and are both circular polarization states; the low-frequency vibration is transmitted to the liquid crystal phase modulator through the vacuum cavity for polarization state conversion, and then is reflected to the liquid crystal phase modulator or the vibration detection reflector through the polarization splitting prism, so that the interference type low-frequency vibration of the cold atoms is measured, and decoupling of the two is realized.

The invention relates to the technical field of optical fiber lasers, and provides a middle-infrared band large-range accurate tunable optical fiber laser light source which adopts a large-range tunable 1 [mu] m laser pumping source to obtain ultra-wideband middle-infrared laser output larger than 1000 nm. Comprising a 1 [mu] m wave band tunable pulse seed source, an optical fiber amplifier module, an optical fiber end cap, an end cap coupling device, a hollow-core optical fiber and a small gas cavity, and the 1 [mu] m wave band tunable pulse seed source is a nanosecond pulse laser with the tuning range covering 1024-1080 nm. Based on the direct tuning of the pumping source of the 1 [mu] m wave band, the accurate tuning of the wavelength of the laser of 3 [mu] m-4 [mu] m is directly realized, the tuning is convenient, and a seed source does not need to be added. The pumping source at the 1 [mu] m waveband can obtain high-power laser output more easily, the damage threshold of the hollow-core optical fiber is high, and the mid-infrared output power can be effectively improved. The line width of the gas Raman laser is narrower, and the dispersion of the hollow-core optical fiber is small, so that the output mid-infrared laser has the characteristic of narrow line width.

The invention belongs to the technical field of laser diagnosis, and discloses a device and method for measuring oil and gas reservoir rock organic carbon characteristics, the device comprises an LIBS spectrum system and an ultraviolet Raman laser system, the LIBS spectrum system comprises a nanosecond laser, the nanosecond laser is connected with a microscope through a light guide arm, a reflecting surface of a reflecting mirror is connected with the light guide arm, and the reflecting surface of the reflecting mirror is connected with the ultraviolet Raman laser system. A convex lens is arranged below the reflecting mirror, a detachable spectroscope is arranged above the reflecting mirror, and a CCD (Charge Coupled Device) camera is arranged in the horizontal reflecting direction of the spectroscope. The LIBS spectrum system provided by the invention is simple in light path adjustment; the microscope carrying the CCD camera can observe the surface appearance of the sample at any time. According to the method, the LIBS spectrum system and the Raman spectrum equipment are respectively used for measuring the spectrum data of each shale, the prediction model of the total organic carbon of the shale is constructed, and the rapid measurement of the total organic carbon of the rock can be realized.

The invention discloses a coal preparation plant workshop multi-mode dust particle detection system and method. According to the system, a dust monitoring unit comprises a dust monitoring chamber, a continuous collection mechanism, a continuous detection mechanism and a cleaning mechanism; the continuous collection mechanism comprises a turnover motion assembly, a collection plate, a micro oscillation motor, a drying pipeline, a mass flow controller and a flow pump; the two collecting plates are oppositely mounted at the upper end and the lower end of the supporting frame up and down, and micro oscillation motors are mounted on the opposite surfaces; the drying pipeline is connected in series with the middle section of the chamber air inlet pipeline; the mass flow controller and the flow pump are positioned in the dust monitoring chamber and are sequentially connected in series to the gas outlet pipeline of the chamber; the continuous detection mechanism comprises a CCD module, a Raman laser, an LIBS laser and a spectrometer; the cleaning mechanism comprises a particulate matter collecting device, a cleaning air hole, a flow pump and a mass flow controller; the method comprises the steps of preparation work; debugging the system; monitoring dust particles; and ending the monitoring operation. According to the system and the method, the dust particle detection operation can be continuously realized.

The invention provides a system and a method for fast focusing in combination with Raman laser spots, and belongs to the technical field of optical imaging, the system comprises a spectrum excitation light path, a spectrum receiving light path, an imaging light path and a control system; the spectrum excitation light path, the spectrum receiving light path and the imaging light path jointly form a Raman focusing light path; through fitting calibration preparation of the optimal focal plane, judgment basis of the aggregation fitting process, setting of the aggregation fitting process and starting of the automatic focusing process, rapid focusing is realized, aggregation calculation can be carried out only by reading the laser spot image at the current position, the automatic focusing efficiency is greatly improved, and the automatic focusing precision is improved. The method is of great significance to various applications needing Raman splicing and Mapping, and the overall technical scheme is scientific and reliable in design and suitable for application and popularization.

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 present invention relates to a method for separating and enriching a chlorine-37 isotope using a laser photochemical reaction and, specifically, to a method for separating and enriching a high-purity chlorine-37 isotope, which is essential for a next-generation molten chloride fast reactor (MCFR) and the like, by selectively photolyzing specific isotopic molecules of iodine monochloride (ICl) using a high-power fiber laser or a solid-state Raman laser and reacting same with a radical scavenger to effectively terminate a chain reaction. Accordingly, by employing, as a light source, a single-frequency fiber laser or a solid-state Raman laser that has higher power efficiency and easier maintenance than conventional dye lasers and is capable of achieving high power of several kW or more through modular expansion, mass production on an industrial scale can be realized and the economic feasibility of the process can be significantly secured.

The utility model relates to a Raman laser capable of preventing burnout of a sample. The Raman laser comprises a laser, a collimating mirror, a galvanometer, a dichroscope, a probe tube, a first focus lens, a second focus lens and a Raman signal receiving end. The laser device emits laser, the laser is changed into first parallel light through the collimating mirror to irradiate the galvanometer, the galvanometer is arranged in a swinging mode and reflects the first parallel light passing through the collimating mirror to the dichroscope, the dichroscope reflects the first parallel light reflected by the galvanometer to the probe tube, the first focusing mirror focuses the first parallel light passing through the probe tube to a sample, and the second focusing mirror focuses the first parallel light passing through the probe tube to the sample. Light scattered on the sample returns reversely and becomes second parallel light through the first focus lens, the second parallel light can penetrate through the dichroscope after passing through the probe tube, and the second focus lens focuses the second parallel light penetrating through the dichroscope to the Raman signal receiving end. Point-shaped light spots focused on a sample continuously swing through the galvanometer, so that energy is uniformly dispersed, and the phenomenon that the sample is burnt due to the fact that the light spots are kept at the same position for a long time is avoided.

The invention may be embodied in other forms than those specifically disclosed herein without departing from itMulti-kW-class blue (400-495 nm) fiber-delivered lasers and module configurations. In embodiments, the lasers propagate laser beams having beam parameter products of <5 mm*mrad, which are used in materials processing, welding and pumping a Raman laser. In an embodiment the laser system is an integration of fiber-coupled modules, which are in turn made up of submodules. An embodiment has sub-modules having a plurality of lensed blue semiconductor gain chips with low reflectivity front facets. These are locked in wavelength with a wavelength spread of <1 nm by using volume Bragg gratings in an external cavity configuration. An embodiment has modules having of a plurality of submodules, which are combined through wavelength multiplexing with a bandwidth of <10 nm, followed by polarization beam combining. The output of each module is fiber-coupled into a low NA fiber. In an embodiment a kW-level blue laser system is realized by fiber bundling and combining multiple modules into a single output fiber.

The invention relates to the technical field of in-situ Raman monitoring microwave plasma chemical vapor deposition devices, and particularly discloses diamond growth in-situ Raman test equipment and a Raman test method, the Raman test equipment comprises a growth device and a Raman laser test device; a detection window is arranged on an upper cover of a reaction chamber of the growth device, and a Raman laser testing device with a height adjusting mechanism, an angle adjusting mechanism and a distance measuring adjusting mechanism is arranged on the outer side of the detection window. The three mechanisms cooperate to accurately focus a laser beam on a diamond wafer edge strongest signal area on a deposition table at an optimal incident angle and an optimal working distance; according to the method, in the process of growing the diamond through microwave plasma chemical vapor deposition, Raman spectrums are collected and analyzed in real time, and technological parameters are dynamically fed back and optimized. And finally, high signal-to-noise ratio, in-situ and real-time monitoring and accurate control of the diamond growth process in a high-temperature plasma environment are realized.

The invention relates to a solid Raman laser with an adjustable polarization state and a working method thereof, and belongs to the technical field of lasers. The laser comprises an LD pumping source, a fundamental frequency light input mirror, a laser working substance, a Q-switched working substance, a fundamental frequency light output mirror, a Raman cavity input mirror, an a-cut anisotropic Raman crystal, a Raman cavity output mirror, a beam splitter, a polaroid and a power meter which are sequentially arranged along a light path, and an oscilloscope is arranged on one side of the beam splitter. By accurately controlling the orientation of the anisotropic Raman crystal, the elliptical polarization passive Q-switched Raman laser can be switched among different polarization states, and has the advantages of compact structure, easiness in integration and controllable Raman light polarization state.

The invention discloses a quantitative detection device and a quantitative detection method for multiple types of side walls of a silicon carbide crystal bar, and belongs to the technical field of silicon carbide crystal bar detection. The quantitative detection device comprises a three-dimensional adjusting table, a distance measuring mechanism, a Raman detection mechanism, a conveying mechanism, a visual judgment mechanism and a control mechanism, wherein the three-dimensional adjusting table is used for placing a silicon carbide crystal bar to be detected and driving the silicon carbide crystal bar to be detected to rotate in a three-dimensional manner; the ranging mechanism is used for testing the thickness of the to-be-tested silicon carbide crystal bar; the Raman detection mechanism comprises a Raman detector, a detection pipeline, a corner lens and a detection port; the transmission mechanism is used for adjusting the distance between the three-dimensional adjusting table and the detection port; if focusing is abnormal, the visual judgment mechanism transmits information to the control mechanism, and the control mechanism controls the three-dimensional adjusting table and the conveying mechanism to achieve focusing. According to the device, the visual judgment mechanism, the three-dimensional adjusting table and the conveying mechanism are matched to realize automatic focusing of Raman laser, so that the detection precision and the detection efficiency are improved, and multi-type quantitative detection on the side wall of the silicon carbide crystal bar is realized.

The application belongs to the technical field of spectral detection, and specifically discloses a kind of characterization methods of fuel cell membrane electrode interface working condition Raman signal, comprising the following steps: constructing fuel cell suitable for Raman test, preparing membrane electrode, assembling fuel cell, assembling in-situ Raman spectrum detection device, detecting fuel cell membrane electrode Raman signal.The application constructs fuel cell window piece, and makes laser passage by constructing window piece, optimizes flow field plate structure and material, avoids the problem that Raman laser cannot be focused due to too large distance from window piece to membrane electrode and the problem that operation platform is unstable due to too heavy weight of fuel cell, and can detect membrane electrode spectral information;The application can be applied to signal detection in different electrocatalytic reaction processes of membrane electrode cathode and anode, thereby providing guidance for the design of electrocatalyst.

The application discloses a method for measuring a detection tilt angle of a two-component atomic shearing interferometer, constructs a tilt angle set of a swing angle device; the angle of a mirror is turned between the time when atoms are subjected to the action of a pi Raman laser and a second pi / 2 Raman laser; a plurality of groups of odd number and even number are alternately detected; all tilt angles in the tilt angle set are traversed; and the actual included angle of the longitudinal direction of a CCD camera imaging surface relative to the Z-axis direction is calculated by fitting. The application also discloses a measuring device for the detection tilt angle of the two-component atomic shearing interferometer. The application enables the current atomic shearing interferometer to accurately measure the tilt angle of the detection system, thereby solving the problems of noise and system error caused by the non-zero return of the tilt angle of the detection system of the atomic shearing interferometer, and suppressing the drift of the differential measurement of the two-component atomic interferometer caused by the change of the tilt angle.

The invention discloses a Raman beam combination laser amplifier, relates to the technical field of laser, and aims to solve the problem of low conversion efficiency of an existing beam combination laser amplifier. A first bowl-shaped reflecting mirror and a second bowl-shaped reflecting mirror are coaxially arranged at the two ends of a columnar reflecting mirror assembly, the concave surfaces face the columnar reflecting mirror assembly, and a Raman laser crystal is arranged in the columnar reflecting mirror assembly; seed light output by the seed light module enters the Raman laser crystal through the center of the first bowl-shaped reflector; and a plurality of beams of fundamental frequency light output by the plurality of fundamental frequency light modules are obliquely incident to the Raman laser crystal from the side surface of the columnar reflector assembly. Each beam of fundamental frequency light of the Raman beam combination laser amplifier can be reflected for multiple times in the amplifier and interacts with the seed light for multiple times, the conversion efficiency of the single beam of fundamental frequency light is improved, the adjustment difficulty of the fundamental frequency light module is low, and the Raman beam combination laser amplifier is suitable for integrated use.

The application discloses a high-power single-mode linear polarization Raman fiber laser based on a multimode optical fiber, and is characterized in that: a Raman gain medium of the laser is a single-clad circularly symmetric step-index distribution large-core multimode optical fiber; a base mode diameter of the step-index large-core multimode optical fiber is more than 65% of a core diameter; a Bragg fiber grating is inscribed in the core of the multimode optical fiber by using a femtosecond laser direct writing technology; a long axis of the grating region is coincided with a base mode field supported by the multimode optical fiber in a radial direction in space and length; the grating forms selective optical feedback only to the base mode in the cavity; a grating region with a difference between the long axis and the short axis forms selective feedback to one polarization state of the base mode; thus, the multimode optical fiber Raman laser effectively suppresses generation of mode instability at a high power level through active mode cleaning, and finally realizes near-diffraction-limited single-mode, high linear polarization and high-power Raman fiber laser output.

The embodiment of the invention discloses a Raman sampling device, which comprises a Raman laser used for outputting a first parallel light beam; the negative lens unit is used for diverging the first parallel light beam output by the Raman laser; the positive lens unit is used for converging the diverged first parallel light beams and integrating the diverged first parallel light beams into second parallel light beams; and the included angle between the axis of the light guide rod and the second parallel light beam is smaller than or equal to 5 degrees, so that the second parallel light beam is reflected in the light guide rod for more than 5 times. The Raman sampling device disclosed by the invention has the beneficial effects that the Raman sampling device realizes uniform distribution of exciting light of large light spots through the beam expanding and light uniformizing structure; a multi-point optical fiber collection structure is adopted, so that the scattered light collection efficiency is improved, and the detection repeatability and representativeness are ensured; the combination of the annular multiple optical fibers and the diffusion film is adopted at the receiving end, the multi-angle collection capacity of Raman scattering light is improved, the Raman sampling device is suitable for rapid detection of heterogeneous samples, and the problem of poor spectrum reproducibility is solved.

The invention discloses a high-efficiency single-wavelength six-channel Raman laser radar atmospheric temperature and humidity profile detection system, and the system employs a high-frequency 355 nm LD pump laser as a light source, and combines a beam expander to optimize the beam divergence angle of a light beam, so as to enhance the excitation efficiency of a backscattering signal. The system adopts a Cassegrain reflection telescope and a light beam terminator to reduce stray light interference and improve the signal-to-noise ratio; the light splitting system separates a 354 nm Raman signal, a 353 nm Raman signal, 355 nm parallel and vertical elastic scattered light, a 386 nm Raman signal and a 407 nm Raman signal through an interference filter and a dichroscope, and six-channel synchronous acquisition is combined with high-speed data acquisition and an inversion algorithm to generate an atmosphere temperature and humidity and aerosol vertical profile. The system is compact in structure, is suitable for field monitoring and unattended long-term operation, has the remarkable advantages of high temporal-spatial resolution, high sensitivity and long-term stability compared with the traditional technology, and provides an integrated, efficient and reliable solution for atmosphere multi-parameter remote sensing measurement.

The present invention discloses a wavelength-tunable Raman fiber laser based on gain control, comprising a second feedback component, a second coupling component, a gain component, a first coupling component, an output component, and a first feedback component, which are sequentially connected to form a linear cavity structure, and further comprising a second excitation component and a first excitation component. The light output by the first excitation component and the second excitation component has different central wavelengths. The present invention has a simple structure, wherein two pump lights of different central wavelengths are selected, each of which is power-amplified by an amplifying component and then coupled into a Raman gain fiber, i.e., a gain component. After the two Raman net gain spectra are superimposed on each other, Raman laser light can be emitted at the point of highest gain in the resonant cavity. Compared with traditional tunable Raman fiber lasers, there is no need for costly wavelength-tunable pump sources and tunable filters, and the resonant cavity structure is simple and compact with low loss.