53 results about "Stimulate raman scattering" patented technology

An Optical Time-Domain Reflectometer (OTDR) trace correction method, an electronic device, and a storage medium are disclosed. The method may include: establishing a parameter decoupling equation according to a fiber loss coefficient and a Stimulated Raman Scattering (SRS) transfer coefficient in response to ignoring an SRS transfer amount amplified or absorbed by an OTDR wavelength in an Optical Transport Network (OTN) service; disabling a service wavelength of an OTN of an optical fiber transmission system, and acquiring, according to the parameter decoupling equation, a first OTDR trace of an OTDR simulation wavelength in the optical fiber transmission system when the service wavelength of the OTN is in a disabled state; determining a fiber loss coefficient according to the first OTDR trace.

The present application belongs to the field of optical microscopic imaging technology, and particularly relates to a coherent Raman microscopic imaging method based on a plane-parallel microcavity. The present application first applies a plane-parallel microcavity structure, i.e. a Fabry-Perot resonant cavity, to a traditional coherent Raman microscopic imaging, designs a microcavity structure with different reflectivity coating, and respectively controls coherent anti-Stokes Raman scattering and stimulated Raman scattering processes, so as to couple spatial structure information of a sample and Raman signals to generate new spectra and images, and respectively realize cavity-enhanced coherent anti-Stokes Raman scattering imaging and cavity-enhanced stimulated Raman scattering imaging. Compared with the traditional coherent Raman microscopic imaging, the present application improves signal intensity, and simultaneously acquires spatial structure information and chemical information of a sample, so as to provide more dimensional information of the sample, and compared with the traditional biological microcavity sensing imaging, can realize fast and label-free imaging, and has wide application prospects in the fields of biomedical detection and the like.

The invention relates to the technical field of ultrafast laser, in particular to an ultraviolet laser damage inhibition method and device for a fused quartz optical element, and the method comprises the steps: obtaining oxy-18 modified DKDP crystals with oxy-18 isotope abundance higher than natural abundance; preparing the oxy-18 modified DKDP crystal into a wave plate matched with a preset ultraviolet laser wavelength; in an ultraviolet laser light path of a laser inertial confinement fusion device, a wave plate is arranged between a linear polarization state output end of ultraviolet laser and a fused quartz optical element; and enabling ultraviolet laser to sequentially pass through the linear polarization state output end and the wave plate to form circularly polarized light, and irradiating the circularly polarized light to the fused quartz optical element. The invention aims to realize the small-scale self-focusing effect of actively inhibiting fused quartz and solve the technical problem that a traditional material cannot be used as a large-aperture wave plate due to over-high transverse stimulated Raman scattering.

The invention relates to the technical field of microscopic imaging, and particularly provides a stimulated Raman scattering microscopic imaging system capable of simultaneously scanning double Raman frequency shift spectrums, which comprises a laser light source driving and modulating unit and a signal detecting and data processing unit, the laser light source driving and modulating unit comprises a dual-channel laser synchronous excitation module, a light beam polarization regulation and power distribution module, a pulse broadening and spectrum focusing module, a dual-channel dual-phase modulation module, a common-path different-time dual-frequency difference module and a laser scanning and telecentric focusing module; and the signal detection and data processing unit comprises a dual-channel orthogonal demodulation module and a scanning driving and signal synchronous acquisition module. Compared with the prior art, the dual-Raman frequency shift spectrum scanning stimulated Raman microimaging device has the advantages that dual-Raman frequency shift spectrum scanning stimulated Raman microimaging with higher acquisition speed, high resolution and wide spectrum coverage range is realized, and the problem of long time consumption for acquiring the complete spectrum of the to-be-tested sample by the traditional single-frequency resonance spectrum scanning stimulated Raman microimaging is solved.

A pulse generation unit generates a driving voltage signal including a pulse signal. A laser oscillation module oscillates a laser beam by carrying out, based on the driving voltage signal, a pulse oscillating operation. When the power command signal has a voltage command value corresponding to a laser power greater than a predetermined laser power during a high period, the pulse generation unit modulates, in a pulsed manner, a voltage value of the high period of the driving voltage signal so as to alternately repeat, for a preset period of time from a rising time of the high period of the driving voltage signal, a high state in which the voltage value is maintained and a low state in which the voltage value is lowered by a predetermined voltage value without being lowered to a voltage value of a low period of the driving voltage signal.

The invention discloses a handheld rapid three-dimensional fundus blood supply imaging system and method.The system comprises an upper computer, a laser excitation module, a probe, a data collection module and a space positioning module, the laser excitation module, the probe, the data collection module and the space positioning module are connected with the upper computer, and the laser excitation module conducts wavelength conversion on input pump laser through the stimulated Raman scattering principle to generate excitation light; the exciting light is then transmitted to the probe for high-speed scanning, the probe receives real-time pose feedback of the space positioning module at the same time so as to eliminate the influence of operation jitter, the data acquisition module pre-processes a photoacoustic signal acquired by the probe and then transmits the photoacoustic signal to the upper computer, and a distribution diagram is generated through an image reconstruction algorithm and analyzed. According to the invention, four clinical troubles of poor molecular specificity, depth-resolution imbalance, low clinical adaptability and deficiency of quantitative standards in the existing imaging technology are fundamentally solved, and a universal tool is provided for early screening of eye ground ischemic diseases.

An optical arrangement for adjusting the wavelength of light, comprising: a first light source arranged to generate a first beam of light at a first wavelength; a second light source arranged to generate seed light at a second wavelength; a first Raman shifting medium arranged to receive the light from the first light source in combination with the seed light from the second light source, and to produce, by stimulated Raman scattering, output light at the second wavelength and having temporal properties determined by those of the first beam of light; a third light source arranged to generate seed light at a third wavelength; and a second Raman shifting medium arranged to receive the output light from the first Raman shifting medium in combination with the seed light from the third light source, and to produce, by stimulated Raman scattering, output light at the third wavelength and having temporal properties determined by those of the output light from the first Raman shifting medium; wherein the third wavelength is greater than the second wavelength, and the second wavelength is greater than the first wavelength; wherein the frequency difference between the first beam of light and the seed light from the second light source is a frequency difference where the first Raman shifting medium exhibits Raman gain; and wherein the frequency difference between the output light from the first Raman shifting medium and the seed light from the third light source is a frequency difference where the second Raman shifting medium exhibits Raman gain. Also provided is a corresponding method of adjusting the wavelength of light.

The application discloses a kind of multi-channel wide spectrum scattered light energy simultaneous measurement device and method, wherein multi-channel wide spectrum scattered light energy simultaneous measurement device mainly includes target chamber, spectrometer, gate camera and multiple scattered light imaging light paths.The present multi-channel wide spectrum scattered light energy simultaneous measurement device and method are used, by setting multiple scattered light imaging light paths, realize multi-channel measurement capability, can accurately give the energy of different wavelengths and total energy, realize the simultaneous measurement of stimulated brillouin scattering and stimulated raman scattering scattered light, provide more reliable diagnostic techniques for the scattered light generated by laser target shooting;At the same time, the present measurement method greatly reduces the use of energy probe, not only saves cost, but also improves diagnostic efficiency;And, the present measurement method can be used not only for high-energy scattered light measurement, but also for other light source intensity analysis and comparison.

The application discloses a few-mode fiber double-cascaded mode converter and a high-power few-mode fiber laser. A core base mode and a core high-order mode converter and a core high-order mode and a cladding mode converter are cascaded on the few-mode fiber. The refractive index modulation distribution of the core base mode and the core high-order mode converter is uniformly distributed in the core center, and is used for coupling the core base mode to the core high-order mode. The refractive index modulation distribution of the core high-order mode and the cladding mode converter is distributed at the junction of the core and the cladding, and is used for coupling the core high-order mode to the cladding to form loss. The few-mode fiber double-cascaded mode converter is connected before an output end cap of the high-power few-mode fiber laser, and can inhibit stimulated Raman scattering in the large-mode-field few-mode fiber laser, so as to improve the output performance of the fiber laser.

The invention relates to the field of chemical oxygen-iodine lasers, in particular to a mid-infrared wavelength conversion method and device of a chemical oxygen-iodine laser. Firstly, a pair of pulsed magnetic field generators is placed on the upper side and the lower side of a gain area of an original continuous wave chemical oxygen-iodine laser; the hydrogen Raman pool is used as a magnetic gain switch to enable the laser to output laser pulses with higher peak power, then 1315nm wavelength laser output by the oxygen-iodine chemical laser is guided into the hydrogen Raman pool, the original 1315nm wavelength laser is converted into 2900nm wavelength laser through Raman scattering to be output, finally, the 2900nm wavelength laser is guided into the vacuum bin containing the iron-doped zinc selenide crystal, and the iron-doped zinc selenide crystal is obtained. And by pumping the iron-doped zinc selenide crystal, the laser with the wavelength of 2900 nm is further converted into intermediate infrared laser pulses with the wavelength of 4000-5000 nm. On the premise that the original laser structure is not influenced, the oxygen-iodine chemical laser has the possibility of being applied to the middle infrared band.

The invention discloses a high-power high-peak optical fiber laser and a using method, the laser comprises a seed source and a three-stage amplifier, a third gain optical fiber of a tail-end amplifier adopts a special structural design, and a central transmission layer is made of a high-damage-threshold or low-nonlinearity material, so that the nonlinear refractive index of the optical fiber is reduced; the occurrence probability of stimulated Brillouin scattering and stimulated Raman scattering is reduced; meanwhile, the continuous gradually-changing core diameter structure of the central transmission layer can dynamically adjust light field distribution, avoid power density concentration and further suppress the thermally-induced self-focusing effect, so that the laser can still work stably when the average power of the laser breaks through the kilowatt level and the peak power of the laser breaks through the megawatt level, and the power output upper limit is remarkably improved; by optimizing the gain optical fiber structure and the multi-stage amplification link, the nonlinear effect is effectively inhibited, the laser output power and stability are improved, and the device is suitable for the high-end fields of industrial manufacturing, aerospace and the like.

This invention relates to the field of high-power fiber laser technology and discloses a method for synergistically suppressing stimulated Raman scattering and mode instability effects in fiber lasers. The fiber laser includes a pump module and a gain module. The gain module includes a gain fiber. By inserting a section of all-solid-state photonic bandgap fiber in the middle of the gain fiber, the synergistic suppression of stimulated Raman scattering and mode instability effects is achieved. The high-loss characteristic of all-solid-state photonic bandgap fiber in the Raman band is used to suppress stimulated Raman scattering. At the same time, the high-loss characteristic of all-solid-state photonic bandgap fiber for higher-order modes is used to filter out higher-order modes, reducing the interference intensity between the fundamental mode and higher-order modes to effectively suppress mode instability effects and achieve high-power single-mode laser output.

This application provides a method and device for optical fiber anomaly detection, relating to the field of transmission technology. The method includes: acquiring the transmit power spectrum of the target optical fiber link under a reference state and the receive power spectrum monitored online; determining the abnormal insertion loss value based on the two total powers; employing a power evolution model that includes the stimulated Raman scattering effect between channels, evolving the transmit power spectrum forward to obtain a forward spectral tilt distribution, and evolving the receive power spectrum backward to obtain a reverse spectral tilt distribution; utilizing the matching characteristic of the forward and reverse spectral tilt distributions at the anomaly location, deriving a closed-form solution calculation formula for optical fiber anomalies to accurately determine the location of the anomaly. This application utilizes only the transmit and receive power spectra of existing transmission channels to achieve fast and accurate optical fiber anomaly localization and quantification through a closed-form solution, requiring no additional hardware, avoiding complex calculations and large-scale data training, and possessing advantages such as strong physical interpretability, good real-time performance, and suitability for low-cost distributed deployment.

The invention discloses a method for reducing the stimulated Raman scattering effect of liquid water and application of the method, and belongs to the technical field of water-guided laser processing. The method specifically comprises the following steps: adding potassium iodate into liquid water to obtain a potassium iodate aqueous solution; according to the invention, potassium iodate (KIO3) is added into liquid water, so that the stimulated Raman scattering effect of 532 nm green laser propagating in water can be greatly reduced, and the effect is better than that of pure water, KCl, NaCl and other substances. When the concentration of potassium iodate is 0.28 mol / L, the effect is optimal, and the stimulated Raman scattering energy can be reduced to about 30% of that of pure water. The solution is applied to a coupling water cavity of a water-guided laser instead of pure water, and stimulated Raman scattering of water can be reduced, so that the energy transmission efficiency is improved, the light beam quality is improved, the system stability is enhanced, the design difficulty is reduced, the processing efficiency and precision are guaranteed, and the solution has an important application prospect in the field of high-energy water-guided laser processing.

The present application relates to the field of ultrafast laser technology, in particular to a fused quartz optical element ultraviolet laser damage suppression method and device, the method comprises: obtaining oxygen-18 modified DKDP crystal with oxygen-18 isotopic abundance higher than natural abundance; The oxygen-18 modified DKDP crystal is prepared into a wave plate matching the preset ultraviolet laser wavelength;In the ultraviolet laser path of the laser inertial confinement fusion device, the wave plate is arranged between the linear polarization state output end of the ultraviolet laser and the fused quartz optical element;The ultraviolet laser passes through the linear polarization state output end and the wave plate in turn, forms circularly polarized light and irradiates to the fused quartz optical element.The purpose is to actively suppress the small-scale self-focusing effect of fused quartz, solve the technical problem that the traditional material cannot be used as a large-aperture wave plate due to the excessively high transverse stimulated Raman scattering.

The invention relates to the technical field of optical fibers, in particular to a double-cladding single-mode strain optical fiber which comprises a fiber core, an inner cladding and an outer cladding, and a middle layer and a leakage layer are arranged between the inner cladding and the fiber core. The refractive index of the middle layer is lower than that of the fiber core, a refractive index barrier is formed, and a light field is limited from diffusing out of the fiber core; the refractive index of the leakage layer is equal to that of the fiber core, a leakage channel is provided for a high-order mode, the high-order mode cannot meet the total reflection condition due to the insufficient incident angle and can permeate into the leakage layer and be lost, only a fundamental mode (LP01) can be stably transmitted in the fiber core, and the phenomenon that when a laser and an amplifier carry out high-power laser output, the high-order mode is damaged is avoided. The invention solves the problem that the improvement of the laser power and the beam quality are limited due to the fact that the double-cladding single-mode strain optical fiber is easily influenced by nonlinear effects such as stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS), meanwhile, the problem of multimode interference is avoided, and the improvement of the laser power and the beam quality in the double-cladding single-mode strain optical fiber and the high stability and low mode field distortion of single-mode transmission are ensured.

The embodiment of the invention provides a Raman amplifier gain adjustment method which comprises the following steps: adjusting DRA-P pumping configuration according to a first preset adjustment target, and determining a third preset adjustment target of a preset virtual intermediate point position according to amplifier performance parameters of a receiving end and a second preset adjustment target of a receiving end OSNR, and adjusting the transmitting terminal configuration of the transmitting terminal according to a third preset adjustment target, detecting the actual OSNR of the receiving terminal, and when the actual OSNR does not meet a second preset adjustment target, circularly and finely tuning the DRA-P pumping configuration and / or the transmitting terminal configuration until the actual OSNR meets the second preset adjustment target. According to the embodiment of the invention, segmented decoupling is carried out on the C + L system, and the gain of the amplifier is adjusted and optimized according to the sequence of the receiving end, the transmitting end and the whole, so that the problem that in the prior art, the stimulated Raman scattering effect exists between the pumping wavelengths of the Raman amplifier in the C + L system and between the service light of the C wave band and the service light of the L wave band can be solved; and the overall optical signal-to-noise ratio performance of the C + L system is influenced.

The application discloses a high-power single-mode optical fiber laser, which comprises an oscillator and an amplifier, wherein the oscillator comprises a forward pumping module (1), a high-reflection fiber grating (2), a low-doped large-mode-field low-numerical-aperture gain optical fiber (3), a low-reflection fiber grating (4), a backward pumping module (5) and a laser output module (6); the amplifier comprises a seed source (7), the forward pumping module (1), the low-doped large-mode-field low-numerical-aperture gain optical fiber (3), the backward pumping module (5) and the laser output module (6); the low-doped large-mode-field low-numerical-aperture gain optical fiber is a rare earth ion doped optical fiber with low absorption coefficient, large core mode field diameter and small numerical aperture at the maximum absorption coefficient wavelength. The application simultaneously suppresses mode instability effect and stimulated Raman scattering effect, and has lower photon darkening effect.

This invention provides a U-band high-energy square-wave pulsed Raman light source module. It first achieves initial stable amplification of the seed light through forward pumping with a 100-watt pump source, followed by high-energy main amplification through reverse pumping with a kilowatt-level pump source. Both stages of Raman amplification utilize highly nonlinear optical fibers as the gain medium to significantly enhance the stimulated Raman scattering effect, efficiently converting pump light energy into signal light and improving overall Raman gain and energy conversion efficiency. Simultaneously, it balances the stability of the amplification process with the integrity of the pulse waveform, thereby achieving a smooth, step-by-step amplification of the U-band pulsed seed light. Ultimately, it stably outputs high-energy U-band square-wave pulsed light with a single pulse energy ≥5μJ and a pulse width of 80–120ns, significantly improving the light source's output performance and better meeting the application requirements of long-distance fiber optic communication expansion and atmospheric methane remote sensing.

The invention relates to an SRS crystal anti-damage laser energy homogenizing device based on a microlens array, and belongs to the technical field of short pulse laser. A pump laser, a light beam isolation system, a light beam energy adjusting system, a color separation mirror, a micro-lens array and a stimulated Raman scattering medium pool are sequentially arranged in the light path direction. The micro-lens array integrates a plurality of micro-lens units and is used for dividing a pump beam emitted by the pump laser into a plurality of sub-beams. The method is used for solving the technical problems that in the pulse compression technology, energy of Gaussian beams at a focus is highly concentrated, local power density is extremely prone to exceeding a crystal damage threshold value, irreversible permanent damage is caused, and energy conversion efficiency is low.

Disclosed herein are methods, devices, apparatuses, and non-transitory computer readable media for signal communication via hollow fiber using stimulated Raman scattering (HC-SRS). Such use of HC-SRS can cause amplification of the signal as it is transmitted through the hollow fiber. Such use of HC-SRS may have (A) reduced signal loss during transmission, (B) reduced latency time as compared to optical signal propagating through a solid core optical fiber, (C) increase a distance between repeaters required for signal transmission, or (D) any combination of (A) (B) and (C); with any of (A) and (C) being compared to any of the currently used signal transmission methodologies disclosed herein.

The invention discloses a few-mode fiber double-cascade mode converter and a high-power few-mode fiber laser. A fiber core fundamental mode and fiber core high-order mode converter and a fiber core high-order mode and cladding mode converter are cascaded on a few-mode fiber; the refractive index modulation distribution of the fiber core fundamental mode and fiber core high-order mode converter is uniformly distributed in the center of the fiber core and is used for coupling the fiber core fundamental mode to a fiber core high-order mode; the refractive index modulation of the fiber core high-order mode and cladding mode converter is distributed at the junction of the fiber core and the cladding, and is used for coupling the fiber core high-order mode into the cladding to form loss. The few-mode fiber double-cascade mode converter is connected in front of an output end cap of a high-power few-mode fiber laser, so that stimulated Raman scattering in the large-mode-field few-mode fiber laser can be inhibited, and the output performance of the fiber laser is improved.

The invention discloses a method for inhibiting a stimulated Raman scattering effect by a high-power laser shutter, and the method comprises the steps: designing and manufacturing a composite structure Raman inhibition type fiber grating in an output optical fiber of the high-power laser shutter, and filtering out the residues in the output laser of a laser device and Raman light excited during the transmission of a long-distance energy transmission optical fiber. The SRS effect excitation threshold value is improved through the SRS effect excitation threshold value, the limitation of the SRS effect on the length of an output optical fiber of the laser is eliminated, the signal-to-noise ratio is improved, Raman return light is reduced, stable and reliable laser output is achieved, and the SRS effect excitation threshold value has the advantages of being high in SRS effect suppression rate and low in insertion loss.

Disclosed herein are methods, devices, apparatuses, and non-transitory computer readable media for signal communication via hollow fiber using stimulated Raman scattering (HC-SRS). Such use of HC-SRS can cause amplification of the signal as it is transmitted through the hollow fiber. Such use of HC-SRS may have (A) reduced signal loss during transmission, (B) reduced latency time as compared to optical signal propagating through a solid core optical fiber, (C) increase a distance between repeaters required for signal transmission, or (D) any combination of (A) (B) and (C); with any of (A) and (C) being compared to any of the currently used signal transmission methodologies disclosed herein.

The present disclosure relates to a method of providing light. The method comprises: providing a chamber filled with a gas; injecting a pump pulse train into the chamber with pulses being spaced by a pump pulse interval; generating a frequency-converted pulse train by frequency conversion via stimulated Raman scattering with the gas, wherein the pulses of the pump pulse train induce coherent oscillations of the gas which facilitates said stimulated Raman scattering, the coherent oscillations having a dephasing time; and outputting the frequency-converted pulse train. A ratio of the pump pulse interval to the dephasing time is at most 10.0. Some pulses of the pump pulse train each serves both to: generate a pulse of the frequency-converted pulse train via coherent oscillations induced by previous pulse(s) of the pump pulse train; and enhance the coherent oscillations for the conversion of a subsequent pulse of the pump pulse train. [Fig. 2b]

The invention discloses an on-chip stimulated Raman scattering gas sensing system and method, and particularly relates to the technical field of gas analysis and measurement. According to the system, pump light and Stokes light interact with gas to be detected in a sensing waveguide evanescent field area, the Raman scattering process of gas molecules is enhanced, and Stokes light Raman gain signals related to gas concentration are obtained. In order to suppress Raman background noise caused by a waveguide material, different polarization modes of Stokes light are introduced into a sensing waveguide, pump light is filtered out through a micro-ring resonator and a polarization beam splitter, and a TE fundamental mode and a TM fundamental mode of the Stokes light are separated; the balance photoelectric detector is used for carrying out differential processing on Raman gain signals corresponding to the two polarization modes, so that the signal-to-noise ratio and the sensitivity of gas detection are improved. And meanwhile, the laser, the sensing waveguide and the detection unit are integrated, so that the device has the advantages of compact structure, low power consumption and high sensitivity, and can realize ppm-magnitude gas detection.

An all-fiber laser system includes a gain fiber and a fiber-based optical coupling structure configured to introduce pump light into a signal fiber. The optical coupling structure provides intrinsic isolation of pump fibers from backward-propagating optical radiation generated in the gain fiber, including backward-propagating signal light and stimulated Raman scattering (SRS) light. By structurally suppressing coupling of the backward-propagating optical radiation into the pump fibers, the laser system mitigates population inversion collapse and suppresses laser instability and self-pulsation induced by optical back reflection during processing of reflective materials. The system enables stable continuous operation at multi-kilowatt output power without reliance on free-space optical isolators, circulators, or active shutdown mechanisms, thereby improving reliability of pump light sources and protecting an output fiber during high-power laser operation.

The invention discloses a stimulated Raman scattering suppressor as well as a preparation method and device thereof, and a chirp tilted fiber bragg grating is prepared in a fiber core of a double-clad fiber by utilizing a femtosecond laser direct writing technology so as to obtain the stimulated Raman scattering suppressor introduced with the chirp tilted fiber bragg grating. According to the method and the device provided by the invention, the femtosecond laser direct writing technology is utilized, the chirp tilted fiber bragg grating is directly prepared in the fiber core of the large-core-diameter double-clad fiber through the coating layer, and the fiber does not need to be pre-processed, so that the preparation efficiency can be improved. The structure of the chirp tilted fiber bragg grating can be flexibly controlled based on the core diameter of the optical fiber and the size of the required wavelength, the stimulated Raman scattering suppression requirements of different power levels and working wavebands are met, and the chirp tilted fiber bragg grating is suitable for high-power optical fiber lasers, high-power optical fiber amplifiers and high-power communication transmission systems.

The invention discloses a signal processing method and device, an optical amplifier, a storage medium and a computer program product. The method comprises the steps that an optical amplifier determines at least one target wavelength corresponding to at least one optical signal, and the optical amplifier is used for compensating power loss in the optical signal transmission process; selecting a first target wavelength from the at least one target wavelength, and obtaining a first value by using the first target wavelength and at least one second target wavelength in the at least one target wavelength, the first value represents a power loss difference value of a second optical signal of each second target wavelength in the at least one second target wavelength relative to a first optical signal of the first target wavelength, and the first value is associated with an influence degree of stimulated Raman scattering in an optical signal transmission process; and determining the output power of the at least one optical signal by using the first value.

The application belongs to the field of Raman laser, and particularly relates to a high-repetition-frequency high-energy pulsed Raman laser with backward scattering output, which comprises a dichroic mirror, a Raman cell A, a 45-degree reflecting mirror, a plano-convex lens and a Raman cell B arranged in sequence along the direction of laser emission of a pumping laser; the laser passes through the dichroic mirror, the Raman cell A, the 45-degree reflecting mirror, the plano-convex lens and the Raman cell B in sequence, wherein the first-order Raman laser is generated in the Raman cell B, the forward transmission Raman laser is absorbed by the inner wall of the Raman cell B, the backward transmission Raman laser returns to the Raman cell A as seed light, and the laser entering the Raman cell A is amplified and then the backward first-order Stokes Raman light is finally emitted vertically through the dichroic mirror. The application uses the backward stimulated Raman scattering light as seed light to generate Raman laser after amplification, has low requirement on the laminar flow of Raman medium, good Raman beam quality and relatively simple structure.