556 results about "Cw laser" patented technology

The invention provides a wet-type high-power combined laser cleaning method suitable for a heavily-corroded steel structure. S1, measuring the thickness of a rust layer on the steel surface of the steel structure; s2, liquid is sprayed to the surface of the to-be-cleaned area of the steel structure to form a liquid film, and the liquid film is used for increasing the laser absorptivity of the surface of the rust layer; s3, the to-be-cleaned area is preliminarily cleaned through continuous laser, the rust layer is made to be fluffy and stripped through the thermal expansion effect, and the thickness of the rust layer is reduced to be not larger than the target threshold value of preliminary cleaning; s4, performing fine cleaning by using pulse laser to accurately remove a residual stubborn rust layer; s5, the to-be-cleaned area is washed; the device can effectively remove a rust layer on the surface of the steel, reduce plasma and smoke dust generated in the laser cleaning process, ensure the safety and high efficiency of the cleaning process, adopt the combination of continuous laser and pulse laser, clean in stages, effectively improve the cleaning efficiency, and reduce thermal damage to the surface of the steel.

The invention belongs to the technical field of quantum and biological imaging, and particularly relates to an oral cavity biological imaging device based on a quantum entanglement phase. According to the invention, energy-time entangled photon pairs are generated by using a continuous laser pumping nonlinear waveguide, and signal photons are separated from idler frequency photons through an optical filter; a to-be-measured oral biological sample is placed in the unbalanced interferometer, two interference curves of different phases are obtained by measuring Franson interference between signal photons and idler frequency photons when the biological sample exists or not, and the entanglement phase difference of the two interference curves is calculated. The position of the sample to be detected is changed through the two-dimensional scanning platform, Franson interference is executed, and entanglement phase differences of different positions are obtained. And combining the phase differences to obtain a quantum phase image of the sample. According to the invention, high-precision imaging of a microstructure can be realized; according to the invention, each component can be from a mature photoelectric device, the device has the advantages of miniaturization, integration, practicability and the like, and a new way is opened up for quantum precision measurement and life science development.

The invention relates to a phase-sensitive optical time domain reflectometer based on multi-frequency reference switching. Continuous laser generated by a continuous laser is divided into a local path and a detection path through an optical coupler; the local path is input to the polarization coherent receiving module, the detection path is incident to a light intensity modulator driven by the signal generation circuit module, and the light intensity modulator is converted into a multi-frequency pulse laser sequence with intensity modulation; the multi-frequency pulse laser sequence enters the sensing optical fiber to be measured through the optical circulator; generated Rayleigh backscattered light and local continuous laser are subjected to beat frequency coherent receiving in a polarization coherent receiving module through a circulator; and the signal acquisition circuit adopts a demodulation algorithm to compensate phase drift and sensitivity difference of detection pulse demodulation signals with different frequencies so as to realize dynamic strain sensing. Compared with the prior art, the phase drift and the sensitivity difference between the frequencies are extracted to realize the compensation of the interleaved signals, and the method does not depend on the fixed reference frequency, so that the robustness and the adaptability of the system in a complex environment are remarkably enhanced.

The invention relates to the technical field of additive and subtractive manufacturing, in particular to a full-laser additive and subtractive composite manufacturing method and a full-laser additive and subtractive composite manufacturing device, and according to the method, a current layer is machined by switching pulse laser and continuous laser, and additive and subtractive treatment is conducted on the current layer. According to the additive and subtractive treatment, the distribution of an interface morphology material and an internal structure of a current layer can be changed, and a formed interface layer can regulate and control the flowing state and the internal stress of a molten pool in the subsequent additive process, so that the effects of inducing and refining structure growth are achieved; according to the method, forming of a more precise fine structure can be achieved through cooperation of layer-by-layer material increasing and material decreasing, continuous laser and pulse laser are compositely utilized in the method, the manufacturing precision, the surface quality and the internal quality of an additive manufacturing part can be effectively improved, and the part has the advantage of being good in mechanical property. The device comprises an optical system, the optical system comprises a pulse laser module and a continuous laser module, and the pulse laser module and the continuous laser module are arranged to operate independently or simultaneously.

The invention discloses a coaxial composite laser welding method and a welding method of a flat wire motor winding, and relates to the technical field of laser welding, coaxial composite laser beams are adopted to act on the surface of a high-reflection material to form a welding pool, the coaxial composite laser beams comprise an outer ring laser beam and a core laser beam, the outer ring laser beam is a pulse laser beam, and the core laser beam is a core laser beam; the core laser beam is a continuous laser beam, the continuous laser beam forms a main molten pool, the pulse laser beam forms an auxiliary molten pool, and the main molten pool and the auxiliary molten pool have overlapped parts. The continuous laser and the pulse laser are combined, the main molten pool formed by the continuous laser and the auxiliary molten pool formed by the pulse laser are communicated in an overlapped mode, the pulse laser disturbs molten metal in the auxiliary molten pool and drives the molten metal in the main molten pool to achieve the oscillation stirring effect, and the laser energy absorption efficiency of the high-reflection material can be improved; and the energy distribution of the heat source can be optimized by adjusting the energy proportion and the focus point position, the energy state of the heat source is accurately controlled, and zero splashing is achieved.

The invention discloses an array type optical fiber ultrasonic imaging system based on multi-path delay parallel detection, and belongs to the technical field of ultrasonic detection and imaging. The main working process of the system is as follows: continuous laser output by a laser is modulated into pulse laser to be transmitted to an optical fiber ultrasonic detector array, and ultrasonic waves emitted by an ultrasonic wave generating device act on each detection array element to cause the property change of a detection optical signal; through multi-path time delay with the optical fiber as the medium, the detection optical signal forms different transmission time in each channel, is distinguished in a time division mode and is combined into a single path to be output. After photoelectric conversion, electric signals containing multi-channel detection information are collected in parallel, the signals are analyzed at a terminal processor by means of an imaging algorithm with an array parallel architecture, information of a to-be-detected target is obtained, and image reconstruction is completed. The array type optical fiber ultrasonic imaging system has the advantages of being accurate and rapid in scanning detection, simple and compact in system structure and efficient and high-quality in image reconstruction, and large-scale and low-cost array type optical fiber ultrasonic imaging is achieved.

The invention provides an observation system for bubble motion characteristics. The observation system comprises an experiment water tank; the gas power generation device is used for pumping gas under different power conditions into the experimental water tank to form bubbles, and the gas power generation device is provided with a gas incidence section extending below the liquid level in the experimental water tank; the observation device comprises a camera platform, a continuous laser and a light uniformizing plate, the camera platform comprises a plurality of side high-speed cameras arranged in an array mode and an upper high-speed camera located above a gas incidence section, and the gas incidence section should be located in an observation area of the camera platform; and the data acquisition and control unit is used for controlling the observation device and pre-processing and analyzing the obtained original data to obtain bubble motion characteristics under different experiment conditions, interaction between bubbles caused by bubble motion and influence of the bubble motion on the flow field. According to the invention, the whole process of bubble generation, development, maturation and formation of a boil-vortex structure on the water surface can be observed.

The invention relates to a phase-sensitive optical time domain reflectometer based on a parallel frequency division multiplexing sequence. Continuous laser is divided into a local path and a detection path through an optical coupler; the local path is input to the polarization coherent receiving module, the detection path is converted into a pulse laser sequence with intensity modulation through a light intensity modulator driven by a radio frequency signal provided by the signal generation circuit module, and the radio frequency signal is composed of two frequency division multiplexing sequences with difference; the pulse laser sequence enters the sensing link to be measured to generate Rayleigh backscattered light, and the Rayleigh backscattered light and local continuous laser are subjected to beat frequency coherent receiving through a circulator; and the signal acquisition circuit is used for sampling and analyzing the interference signal, and performing frequency domain comparison on an interleaving result of the two frequency division multiplexing pulse sequences to eliminate a harmonic frequency and retain a real strain signal frequency. Compared with the prior art, the non-harmonic strain signal measurement is realized, the high-frequency response performance and the high-precision strain measurement capability are excellent, and meanwhile, the long-distance coverage capability is also realized.

The invention discloses a short pulse laser assisted continuous laser welding device and method. The method comprises the steps that materials are laid; a welding area is divided, and the whole welding area is divided into small areas; performing feature extraction on the small regions; constructing a speed mapping table according to the extracted different features; and planning a laser scanning path according to the speed mapping table. The short-pulse laser-assisted continuous laser welding device and method have the beneficial effects that near-infrared wavelength laser (such as 1064nm) is selected in the whole welding process, and the characteristics of high reflectivity of titanium alloy to the wavelength, high absorptivity of thermoplastic resin, relatively low absorptivity of a resin part in a thermosetting composite material and poor absorptivity of carbon fibers to the wavelength are utilized; laser energy is mainly concentrated on the thermoplastic resin layer, and local heating is achieved. The method comprises the following steps: dividing a region into small regions, extracting features, constructing a speed mapping table, controlling laser energy input, and reducing heat affected zones of the titanium alloy and the thermosetting composite material.

The invention discloses an underwater navigation positioning method and system based on supercontinuum laser intensity correlation. The system comprises a master control system, a transmitting end underwater base station and a receiving end underwater carrier. The method comprises the following steps: firstly, a main control system generates a super-continuum laser signal with pseudo-random code information, the super-continuum laser signal is separated into optical signals of different wavelength channels through a light splitting module, and the optical signals are respectively sent to underwater base stations uniquely corresponding to the wavelength channels and are emitted; then the underwater carrier receives optical signals from a plurality of base stations, identifies a signal source base station according to wavelength identification, performs correlation operation with a locally copied pseudo-random code sequence, determines signal arrival time TOA and calculates a pseudo-range; and finally, resolving the three-dimensional coordinate and local clock error result of the underwater carrier by combining the pseudo-ranges, absolute positions and transmission delays of the underwater carrier and the at least four base stations. According to the invention, high-precision and high-robustness absolute positioning of the underwater environment is realized, and the reliability of long-time positioning and navigation of the underwater robot is enhanced.

The invention discloses a method and device for optimizing metal powder laying additive manufacturing, the method comprises the steps that optical fiber beam combination is conducted on short pulse optical fiber laser and continuous optical fiber laser which are the same in wavelength to form a composite light source, and the pulse width of the short pulse optical fiber laser is the nanosecond level or the subnanosecond level; the composite light source is output to the galvanometer module through the beam combining optical fiber and then acts on the metal powder bed, and the low-cost and high-efficiency method of full coaxiality and concentricity of lasers of different light sources through the beam combining optical fiber is adopted, so that the printing stability, reliability and large-area uniformity are guaranteed; the short pulse laser and the continuous laser act on an irradiation metal area synchronously and coaxially all the time in the scanning process, metal powder bed melting manufacturing under the force oscillation effect is achieved, and the stability of a keyhole in the additive manufacturing process is improved. According to the method, the pore forming probability of laser powder laying sintering three-dimensional forming can be greatly reduced, the comprehensive mechanical property of a printed piece is improved, and wide popularization and application prospects are achieved.

The invention discloses a continuous scanning half-wave sampling system for a multi-dimensional coherent spectrum, which comprises a continuous laser, continuous laser output by the continuous laser and femtosecond laser pulse output by an ultra-short femtosecond laser pulse generation device are combined and then split, and modulation and time delay are respectively carried out; the multi-dimensional coherent femtosecond laser pulse sequence is used for exciting a fluorescence signal generated by a sample and converting the fluorescence signal into a first electric signal, and the obtained continuous laser carrying different modulation frequencies is converted into a second electric signal; and demodulating the second electric signal by taking a total mixing signal obtained by mixing the multiple paths of modulation signals as a reference, and demodulating the first electric signal by using the second electric signal. The invention further discloses a continuous scanning half-wave sampling method for the multi-dimensional coherent spectrum. The half-wave sampling method is utilized to accurately calibrate optical time delay so as to obtain the multi-phase multi-dimensional coherent spectrum. The sampling step length breaks through the limitation of the minimum sampling step length of traditional stepping collection, and the sampling bandwidth is remarkably improved.

The invention discloses a flying cleaning process for a thinning area of a battery pole piece, and relates to the technical field of laser processing. The method comprises the following steps: S1, selecting a homogenized DOE lens for a pulse laser and / or a continuous laser, arranging the homogenized DOE lens on an external light path, adjusting the angle of the lens to enable laser to vertically and smoothly pass through the center of the homogenized DOE lens, and rotating the homogenized DOE lens to adjust the angle of a shaped light spot to an area to be cleaned after light is emitted; s2, cleaning upper-layer graphite of the coating layer of the thinned area by adopting a continuous laser / pulse laser until the copper foil is slightly exposed, and uniformly cleaning the thinned area; and S3, cleaning the residual bottom layer graphite of the coating layer in the thinned area by using a pulse laser. The cleaning process is simple and reliable, the yield of the laser cleaning thinned area can be effectively improved, the lossless cleaning effect is achieved, and meanwhile the laser cleaning efficiency can be remarkably improved.

The invention belongs to the technical field of optical fiber sensing, and discloses a distributed optical fiber sensing system and method. A narrow linewidth laser is used for emitting continuous laser, a coupler is used for dividing the continuous laser into two paths, one path serves as a local oscillator signal to be input into a receiving unit, and the other path serves as a detection signal to be input into a second modulation unit; the first modulation unit is used for generating an electric modulation signal, and the second modulation unit introduces random phase coding under the action of the electric modulation signal, modulates the amplitude and phase of a detection signal and outputs pulsed light; the amplified pulsed light is output to an optical fiber through a circulator, and a Rayleigh backscattering signal generated by the optical fiber is output to a receiving unit; performing beat frequency on the local oscillator signal and the Rayleigh backscattering signal by using a receiving unit to generate an electric signal; and the data acquisition unit is used for acquiring sensing information. The system has the capability of measuring the power and phase distribution of Rayleigh backscattering signals at the same time, and functions which can be completed by two sets of systems originally can be completed by one set of system.

The invention discloses a cascade up-conversion-based photosensitive material and a preparation method thereof. The cascade up-conversion-based photosensitive material comprises a photopolymerization material, holmium-ytterbium rare earth nanoparticles and a triplet-state up-conversion material, the photopolymerization material comprises a photoinitiator and a polymerization monomer; the triplet-state up-conversion material comprises a sensitizer and an annihilation agent; the polymeric monomer adopts a liquid monomer or oligomer containing more than 3 active groups. Through the synergistic effect of the photopolymerization material, the holmium-ytterbium rare earth nanoparticles and the triplet state up-conversion material, a brand new cascade up-conversion mode is formed, the dispersivity of up-conversion photopolymerization of traditional thulium-ytterbium nanoparticles is overcome, and low-power, low-cost and high-precision continuous laser micro-nano structure processing is realized.

The invention provides a two-dimensional composite laser cleaning device, and relates to the technical field of laser cleaning, the two-dimensional composite laser cleaning device comprises a two-dimensional galvanometer scanning combination package, a pulse laser collimating lens, a light path collimating turn-back package, a continuous laser collimating lens, a plane field lens and a working platform, the pulse laser collimating lens and the continuous laser collimating lens are connected to the two ends of the light path collimation turn-back package respectively, a mechanical arm switching module is arranged on the light path collimation turn-back package, the pulse laser collimating lens is used for being connected with a nanosecond pulse laser, the continuous laser collimating lens is used for being connected with a continuous laser, and the mechanical arm switching module is used for being connected with the nanosecond pulse laser. And the light path collimation turn-back packaging is used for carrying out collimation and compression combination on the pulse laser and the continuous laser so as to output a parallel composite light beam. According to the invention, field curvature and distortion can be effectively suppressed, and the phenomenon of non-uniform energy of light beam scanning is improved.

The invention discloses a wire bonder transducer, a wire bonder and a vibration amplitude detection and calibration method, and realizes non-contact and high-sensitivity amplitude detection of a vibration part of the transducer by integrating a laser interference detection part in the wire bonder transducer. Continuous laser with a stable wavelength is output through the laser, signal light and reference light are split through the optical splitter, the signal light irradiates the vibration part of the transducer and is reflected, the reference light and the reflected light are combined in the beam combiner to form interference fringes, and finally a phase change signal is collected through the photoelectric detector. According to the invention, the micron-sized vibration displacement of the transducer in the working state can be extracted in real time with high precision. Compared with a traditional judgment mode, the method has the advantages that an objective and quantifiable detection means is provided, the precision and the automation degree of transducer performance consistency evaluation are effectively improved, the method can be widely applied to production line detection, equipment calibration, online quality control and other scenes of wire welding equipment, and the method has important significance in guaranteeing the welding stability and improving the packaging yield.

The invention discloses an anti-unmanned aerial vehicle or unmanned aerial vehicle cluster device and method, and relates to the technical field of anti-unmanned aerial vehicles. The device comprises a radar detection module, a data processing unit, a control system, a pulse laser transmitter, a light beam control and focusing system, a cooling system and a power supply system. According to the device, large-energy pulse laser is integrated into a laser anti-unmanned aerial vehicle device, the pulse laser can release extremely high peak power in an extremely short time, a strong photo-thermal and light pressure effect is instantly generated, an unmanned aerial vehicle body is instantly punctured, the destroying time is greatly shortened, and the problem that the efficiency is low in an existing continuous laser anti-unmanned aerial vehicle technology is solved.

According to the roadbed pavement flatness detection device provided by the invention, when the roadbed pavement flatness detection device moves on a flat pavement, the movable assembly is kept at the initial position due to the flat pavement, and laser passes through the light transmission hole from the emitter and is directly emitted to the receiver, so that the pavement is flat. When the roadbed pavement flatness detection device passes through an uneven pavement, the movable assembly moves relative to the main body according to the convex-concave change of the pavement, and the position of the light hole is changed, so that the laser is shielded and cannot be directly emitted to the receiver, and the pavement is uneven. Through the continuous laser detection of the roadbed pavement flatness detection device, the rapid and continuous detection of the large-area pavement flatness can be realized, and the detection efficiency is greatly improved.

The invention relates to the technical field of liquid phase chips, in particular to an autoantibody spectrum detection platform based on a liquid phase chip technology, and the method comprises the following steps: preparation and functionalization of quantum dot encoding microspheres; the core-shell structure quantum dots are used as coding elements, and fluorescence coding combination of more than 1000 is realized by regulating and controlling the size, 3-10nm, Mn < 2 + > doping and spatial distribution of the quantum dots. The method has the advantages of super multi-target detection, super sensitivity, strong anti-interference capability and intelligent analysis, in the actual process, the core-shell structure quantum dots are adopted as coding elements, more than 1000 fluorescent coding combinations are realized by regulating and controlling the size, doping and spatial distribution of the quantum dots, high-density coding is realized by utilizing three-parameter coding and an orthogonal decoupling algorithm, and the method is suitable for large-scale industrial production. More types of autoantibodies can be detected at the same time, so that the detection flux is improved; the surfaces of the quantum dots are coated with silicon dioxide layers, and the fluorescence intensity is attenuated by lt under continuous laser irradiation; and the stability of a fluorescence signal in the detection process is ensured.

The invention discloses a coaxial double-beam welding method and coaxial double-beam welding equipment, and relates to the technical field of metal laser welding methods.The coaxial double-beam welding method comprises the following steps that S1, a to-be-welded workpiece is pretreated, and then the to-be-welded workpiece is fixed; s2, the continuous laser beam and the pulse laser beam are coaxially coupled into a composite laser beam, the spraying direction of molten pool shielding gas is adjusted, and the sprayed molten pool shielding gas is aligned to a molten pool; s3, the composite laser beam is adjusted, and the spot diameter d of the composite laser beam irradiating the molten pool is controlled; s4, the average output power and the defocusing amount of the continuous laser are set to be delta z2, the average output power and the defocusing amount of the pulse laser are set to be delta z2, and the frequency is f and the pulse width; and S5, welding is conducted, and meanwhile molten pool shielding gas is sprayed to the molten pool till welding is finished. Continuous laser and pulse laser are coaxially coupled to form a composite laser beam, the composite laser beam jointly acts on a molten pool, the temperature distribution gradient is accurately controlled by regulating and controlling the coaxial double-beam heat source state, and therefore the problem of thin plate welding deformation is solved.

The invention discloses a device and method for testing performance degradation of a deep ultraviolet fused quartz material, and the method comprises the steps: employing a continuous laser beam with the wavelength of 213nm as a detection light beam, and simultaneously monitoring the transmittance change of the detection light beam after the detection light beam passes through a deep ultraviolet laser irradiation region of the deep ultraviolet fused quartz material and the instantaneous change of the light intensity of a light beam central region; the color center defect concentration change of the deep ultraviolet fused quartz material caused by deep ultraviolet laser irradiation and the absorption change of the deep ultraviolet laser irradiation wavelength are obtained, and the transmittance change of the irradiation laser beam transmitting the deep ultraviolet fused quartz material is monitored at the same time; the performance degradation data of the deep ultraviolet fused quartz material under the irradiation of the deep ultraviolet laser and the contribution of the color center defect generated by the irradiation of the deep ultraviolet laser to the performance degradation are obtained. According to the invention, the contribution of color center defects to performance degradation can be distinguished, the performance recovery mechanism of hydrogen can be measured, and the measurement sensitivity of thermal lens signals can be effectively improved.

The invention discloses a special-shaped hole machining system and a special-shaped hole machining method. The machining method of the special-shaped hole comprises the steps that quasi-continuous laser is adopted for machining in a machining target to form a prefabricated hole; carrying out scanning processing on the prefabricated hole by adopting ultrafast laser according to a layer-by-layer scanning removal mode so as to process the prefabricated hole into a special-shaped hole; and the straight round section of the special-shaped hole is subjected to fine trimming treatment in any one of ultrasonic-assisted mechanical tool cutting machining or ultrasonic-assisted electric spark machining and electro-hydraulic beam machining, so that the taper is eliminated. According to the special-shaped hole machining system and the special-shaped hole machining method provided by the embodiment of the invention, machining of complex special-shaped holes can be achieved, and meanwhile the problems of conicity and wall damage are avoided.

The invention provides a combined laser welding method and device.The method comprises the following steps that linear structured light is adopted to scan a welding seam area of a welding workpiece in the welding path direction, and morphological characteristics of the welding seam area are obtained; determining welding process parameters of the combined laser welding device according to the morphological characteristics and the material characteristics of the welding workpiece; the combined laser welding assembly is driven to move along the welding path, the welding seam area is welded, characteristic parameters of small laser holes in the welding seam area are monitored in real time, and in the continuous laser welding process, if the characteristic parameters exceed a preset range, pulse laser is switched to conduct welding on the welding seam area; and in the continuous laser welding process, if the characteristic parameters exceed the preset range, continuous laser is switched to conduct welding on the welding seam area. The problem that thermal stress is not uniform when different materials are welded can be effectively solved, the uniformity and strength of a welding area are guaranteed, high-precision welding of structural parts in complex shapes is achieved, and the welding precision and consistency are guaranteed.

The invention discloses double-laser machining equipment and method for tool machining. The double-laser machining equipment comprises a tool clamping mechanism and a gantry mounting frame which are arranged on a workbench. The cutter clamping mechanism drives the cutter to rotate; the infrared continuous laser processing head and the purple picosecond laser processing head are respectively mounted on the gantry mounting frame through a lifting mechanism, an infrared continuous laser beam emitted by the infrared continuous laser acts on the cutter through the infrared continuous laser processing head, and a purple picosecond laser beam emitted by the purple picosecond laser acts on the cutter through the purple picosecond laser processing head; the cutter clamping mechanism, the lifting mechanism, the infrared continuous laser, the infrared continuous laser machining head, the purple picosecond laser and the purple picosecond laser machining head are all electrically connected with the controller. The infrared continuous laser and the purple picosecond laser are integrated in the same equipment, the cutter is modified through double-laser cooperation, dynamic adjustment of laser parameters is achieved in combination with the lifting mechanism and the controller, the heat influence is effectively reduced, and the machining quality stability is improved.

The invention belongs to the technical field of wind tunnel measurement, and discloses a method and system for visualization of a large-scale high-enthalpy wind tunnel flow field structure. The method comprises the following steps: generating sheet light of which the width is greater than or equal to 300mm by using continuous laser of which the wavelength is 811.5 nm, and irradiating a wind tunnel flow field to excite naturally existing metastable state argon atoms and generate a fluorescence signal; collecting the fluorescence signal through a narrow-band filter with the central wavelength of 910nm and the bandwidth of less than or equal to 5nm in a direction perpendicular to a sheet light plane; performing synchronous scanning and displacement measurement on the sheet light and the signal acquisition device to obtain three-dimensional flow field data; and based on the three-dimensional flow field data, reconstructing a hypersonic speed wind tunnel flow field structure with the total enthalpy being greater than or equal to 10MJ / kg and the wind tunnel caliber being greater than or equal to 500mm. According to the invention, the problem that the prior art cannot satisfy the visualization of the fine flow field of the large-scale high-enthalpy wind tunnel is effectively solved, the tracing-free and wide-range measurement capability suitable for the extreme environment and the high model near wall surface is realized, and a new powerful tool is provided for the hypersonic velocity research.

The invention relates to a low-repetition-frequency narrow-pulse-width pulse fiber laser beneficial for inhibiting ASE light, and the laser comprises a low-repetition-frequency narrow-pulse-width seed source which is used for providing a low-repetition-frequency narrow-pulse-width seed pulse with the repetition frequency of 1-500 KHz and the pulse width of 1-50 ns, and outputting the seed pulse to a wave combining module; the continuous injection source is used for providing continuous laser and outputting the continuous laser to the wave combining module; wherein the peak power of the seed pulse is at least 10 times of the peak power of the continuous laser, and the average power of the seed pulse is equal to-0.5 to 1.5 times of the average power of the continuous laser; the wave combining module is used for simultaneously transmitting the seed pulse and the continuous laser to the amplification module; the amplification module is used for amplifying the power of the seed pulse to form pulse laser with low repetition frequency, narrow pulse width and high peak value and transmitting the pulse laser to the filter; wherein in the seed pulse power amplification process, the continuous laser forms a gain suppression effect on the ASE light; the filter is used for filtering the continuous laser provided by the continuous injection source and outputting amplified pulse laser, the continuous injection source is utilized in the seed pulse amplification process, generation of ASE light is effectively restrained, the control difficulty of the system for the pumping source and the injection source is lowered, the signal-to-noise ratio of the system is further improved, and the service life of the system is prolonged. And powerful support is provided for application of the fiber laser in multiple fields.

The invention provides a continuous laser single-photon ranging method, device and equipment, which can be applied to the technical field of laser radars. The method comprises the following steps: periodically modulating a received continuous light wave to generate a target light signal; transmitting the target optical signal to a target object, and receiving an initial echo optical signal reflected from the target object; converting the initial echo optical signal into an electric pulse signal; the output moment of the electric pulse signal and the period starting moment of the target optical signal are measured, and the period starting moment of the target optical signal is represented as the emission moment of the target optical signal; performing signal processing on the output moment of the output electric pulse signal to generate a target echo optical signal; generating an initial delay moment of the target echo optical signal according to the waveform of the target echo optical signal; and determining a target distance according to the initial delay time of the target echo optical signal and the period starting time of the target optical signal.

The quantum current transformer based on the optical fiber isolation microwave transmission comprises a high-voltage primary side which comprises a magnetic shielding ring and an NV color center magnetic sensing probe module, and a magnetic sensing probe is arranged in the magnetic shielding ring; at the low-voltage secondary side, the microwave system is used for generating radio-frequency signals in a preset frequency range and transmitting the radio-frequency signals to the NV color center magnetic-sensing probe module, the laser system is used for generating continuous laser and transmitting the continuous laser to the NV color center magnetic-sensing probe module, and the microwave system and the laser system are used in cooperation to drive the NV color center to generate fluorescence signals representing the magnetic field intensity. A fluorescence signal is transmitted to the data processing system to calculate to-be-detected current information; wherein the microwave system is connected with the NV color center magnetic sensing probe module through an optical fiber, the microwave system modulates the radio frequency signal into an optical signal, transmits the optical signal to the NV color center magnetic sensing probe module, and restores the optical signal into the radio frequency signal in the NV color center magnetic sensing probe module to be received. According to the transformer, stable transmission of microwave signals under the high-low voltage isolation condition is achieved, the design is reasonable and exquisite, and the measurement precision is high.

The invention provides a low-cost ytterbium-doped Yb calcium silicate niobium aluminum gallium laser crystal and a preparation method and application thereof. According to the invention, Al < 3 + > is introduced to replace 50% Ga < 3 + >, Yb < 3 + > ions are doped, and the Yb: Ca3NbAl < x > Ga < 3-x > Si2O14 laser crystal (0lt; xlt; and 3) the raw material cost is greatly reduced, the growth period is shortened, the laser performance of the crystal is improved, the absorption cross section and the emission cross section of the crystal are increased, the half-peak width of absorption and emission peaks is broadened, the oblique efficiency and the light conversion efficiency of continuous laser output are further improved, the laser threshold value is reduced, and watt-level continuous laser output is obtained.