1387 results about "Laser fiber" patented technology

The invention discloses a three-dimensional cutting dynamic parameter adjusting system and method based on deep learning, and relates to the technical field of application of three-dimensional five-axis fiber laser cutting machines in the automobile manufacturing industry, and the three-dimensional cutting dynamic parameter adjusting system comprises a multi-mode sensor cluster, an edge calculation unit, a closed-loop control module and an AI model library, the multi-mode sensor cluster collects cutting data, the edge calculation unit receives the multi-mode sensor data and outputs dynamic adjustment parameters, and the closed-loop control module transmits the dynamic parameters to the laser generator and the five-axis motion controller through a high-speed communication bus to form a'sensing-decision-execution 'closed loop. The cutting state and risk are sensed in real time by designing a multi-mode sensor for collaborative decision, the problems that manual experience depends on and dynamic response lags are solved, the reject ratio is reduced, and the response speed is increased.

The invention provides a quasi-continuous thulium-doped fiber laser capable of synchronously suppressing relaxation oscillation and self-pulse, relates to the technical field of fiber laser, and is used for simultaneously realizing suppression of a self-pulse effect and a relaxation oscillation peak. Comprising a continuous driving module, a pulse driving module, a semiconductor laser pumping source, a high-reflectivity fiber bragg grating, a low-reflectivity fiber bragg grating, a beam combiner, a thulium-doped gain fiber, a passive fiber, a cladding pumping stripper and a laser output port, the continuous pump light and the pulse pump light are respectively driven by the continuous driving module and the pulse driving module to output continuous pump light and pulse pump light; the high-reflectivity fiber bragg grating and the low-reflectivity fiber bragg grating form a resonant cavity structure, the thulium-doped gain fiber serves as a gain medium of the thulium-doped fiber laser and absorbs pump light to generate population inversion, laser oscillation is formed by combining the resonant cavity of the laser, relaxation oscillation suppression is achieved, and meanwhile longitudinal mode distribution of the laser is effectively disrupted.

The invention belongs to the technical field of laser welding, and discloses a multi-parameter cooperative control laser welding method and system.The method comprises the steps that a laser energy control model is established based on material strength-thickness-gap ternary coupling, and the output power of an optical fiber laser is controlled; coaxial three-layer gradient gas is adopted for protection of a welding area, preheating before welding and double-temperature-zone gradient annealing after welding are adopted, the output power of an optical fiber laser and the three-layer gradient gas protection flow are regulated and controlled in real time through combination of multiple sensors and a control algorithm, the temperature of a heat affected zone is monitored in real time, and a cooling nozzle is controlled for cooling. And continuous parameter optimization is achieved through machine learning, and multi-parameter control laser welding is achieved.

The invention discloses a narrow pulse generation system and method of an FPGA integrated fiber laser, and belongs to the field of all-digital fiber laser control. The narrow pulse generation system comprises a multi-phase clock generation module, a dynamic delay chain module, a pulse width search module, a signal selection module, a logic operation module, a frequency control module, a self-calibration module and an LVDS driving module which are in synergistic effect. The multi-phase clock generation module is used for realizing rough delay adjustment of nanosecond stepping; the dynamic delay chain module is used for realizing fine delay adjustment of picosecond stepping; therefore, based on the FPGA integrated design, an external delay chip and a high-frequency peripheral circuit are not needed, the hardware complexity and cost are reduced, and the anti-interference capability is high; picosecond-level stepping pulse width adjustment is realized through a two-level structure of nanosecond-level coarse adjustment and picosecond-level fine adjustment, and the limitation of a traditional FPGA (Field Programmable Gate Array) integration scheme is broken through; time delay deviation caused by environment change and hardware drift is considered, temperature compensation and TDC calibration are carried out, and the stability of pulse width is ensured.

The invention relates to the technical field of fiber laser rapid interlocking protection scheme design, in particular to a fiber laser rapid interlocking protection circuit, and aims to solve the problems of long protection delay and low reliability of an MOPA structure laser in an abnormal state. The circuit comprises an interlocking protection bus, an interlocking control circuit and a multi-stage interlocking switch circuit. When an abnormity occurs, the interlocking control circuit detects a signal and triggers the switch circuit to quickly respond through bus level change: the main amplification stage LD is immediately turned off by the main amplification interlocking switch circuit, and the pre-amplification stage LD is sequentially turned off after the pre-amplification interlocking switch circuit delays. Therefore, sub-millisecond protection is realized, the working time sequence of the laser is strictly followed, and damage expansion is avoided. The circuit is integrated in the laser without depending on an external system, so that the reliability is improved and the structure is simplified. The method is suitable for various fiber lasers, and effectively prevents burning failure.

The invention relates to the technical field of lasers, in particular to an air-cooled fiber laser. The air-cooled fiber laser comprises a heat dissipation structure which comprises a pumping source radiator and a fiber coiling radiator which are connected, the pumping source radiator is provided with a first air channel, the fiber coiling radiator is provided with a second air channel, and the first air channel and the second air channel are communicated with each other; the pumping source is arranged on the pumping source radiator so as to transfer heat into the pumping source radiator; the active fiber is wound on the fiber coiling radiator; a forced heat exchanger. The pumping source radiator and the coiled fiber radiator are separated, and the independently designed structure breaks through the limitation that the size is difficult to reduce due to mutual restriction of the traditional integrated radiating structure. Due to the modularized and distributed layout, each heat dissipation unit can be subjected to optimal size design according to the thermal load of the heat dissipation unit, so that the structure is compact and reasonable, the size of the laser is reduced, the overall size and weight are reduced, and portability and light weight are realized.

The invention discloses a high-power picosecond pulse train laser with programmable sub-pulse energy and a method, and relates to the related technical field of lasers, the high-power picosecond pulse train laser comprises a mode-locked fiber laser, an acousto-optic modulator and a solid amplification chain which are sequentially arranged along an optical transmission path; the mode-locked fiber laser generates a mode-locked picosecond pulse sequence; the acousto-optic modulator performs pulse selection and pulse string grouping on the mode-locked picosecond pulse sequence, and performs pre-programming shaping on sub-pulse energy in a pulse string according to set intensity distribution to generate a pre-shaped pulse string; the solid amplification chain comprises at least one stage of solid amplifier, and the solid amplifier comprises a dichroscope, a laser gain crystal, a coupling optical assembly and an LD pumping source; and the dichroscope is used for focusing the pre-shaped pulse string amplified at the previous stage and the LD pump light transmitted by the coupling optical assembly into the laser gain crystal. Independent programmable regulation and control of the energy of each sub-pulse in the pulse string are realized, and the energy distribution of each sub-pulse in the pulse string can be flexibly adjusted.

The invention discloses a laser welding method for a copper-aluminum composite material, which comprises the following steps of: performing upsetting thinning treatment on a three-layer sandwich structure base material to ensure that the total thickness of a welding area is 1.5 mm, the thickness of an aluminum layer is 0.9-1.1 mm (the deformation rate is 10-30%), the thickness of a copper layer is 0.2-0.3 mm, the surface roughness Ra is less than or equal to 1.6 mu m, and the surface roughness Ra of an oxide layer is less than or equal to 5 mu m; a 1064nm optical fiber laser is adopted, welding is conducted at the power of 85%-95%, the speed of 120-150 mm / s and the frequency of 4000-6000 Hz, the fusion depth is 0.3-0.6 mm, and the fusion width is 1.2-2.0 mm. By means of the method, the tensile strength of the connector can be larger than or equal to 110 MPa, the resistivity is smaller than or equal to 2.5 * 10 <-8 > omega.m, the problems that traditional welding strength is low and conductivity is poor are solved, batch quality consistency is ensured, and the method is suitable for the fields of new energy automobiles and the like.

The invention discloses a high-efficiency erbium-ytterbium co-doped fiber laser for long-wavelength peak shifting pumping. The laser is characterized in that pump light enters an active fiber through a pump coupling device; the active optical fiber is doped with erbium ions and ytterbium ions, part of the pump light entering the active optical fiber is absorbed by the ytterbium ions, and part of the pump light entering the active optical fiber is absorbed by the erbium ions; ytterbium ions are transited from a ground state 2F7 / 2 to an excited state 2F5 / 2 energy level, cross relaxation occurs between the ytterbium ions and ground state erbium ions nearby the ytterbium ions, energy is transferred to the erbium ions, and the erbium ions are relaxed to a 4I13 / 2 energy level after transition from 4I15 / 2 to 4I11 / 2 is completed; erbium ions absorb pump light, transition from a ground state 4I15 / 2 to a 4I11 / 2 energy level and then relaxation to a 4I13 / 2 energy level are carried out, the erbium ions of the 4I13 / 2 energy level generate laser gain of 1.5 microns, and when the gain exceeds loss of a laser resonant cavity formed by the first resonant cavity feedback device and the second resonant cavity feedback device, 1.5 microns-band laser oscillation is formed and is output through the second resonant cavity feedback device. The influence of amplified spontaneous emission of ytterbium ions and excited state absorption of erbium ions on the efficiency of the laser is weakened, and the efficiency of the laser is improved.

The invention relates to a planning method, device and equipment for treating brain glioma through multi-fiber laser ablation. The method comprises the following steps: according to pre-acquired image information of a target patient and a segmentation result of a tumor region, sequentially performing segmentation sampling processing on the image information to obtain a candidate optical fiber path set; screening the candidate optical fiber path set according to an optical fiber planning objective function and an optical fiber planning constraint condition to obtain an intermediate optical fiber path set, and determining the number of optical fibers required by tumor ablation according to the intermediate optical fiber path set; determining a target optical fiber path set from the intermediate optical fiber path set according to the number of optical fibers required by tumor ablation and a predetermined path evaluation score; the target optical fiber path set at least comprises position information corresponding to each target optical fiber path. The method can improve the tumor ablation rate and reduce the use of optical fibers.

A portable air-cooled fiber laser device disclosed by the present invention comprises a box body, a laser pumping source, a fiber output assembly, a power supply assembly, a heat dissipation engine and a control circuit are integrated in the box body, the power supply assembly adopts a drawable structure, a replaceable battery is arranged in the power supply assembly, and energy supply without an external power supply is realized. The heat dissipation engine is arranged in a sandwich type structure and is composed of a heat dissipation fin set and heat pipes embedded in the heat dissipation fin set, a transverse ventilation heat dissipation channel is formed through a heat dissipation fan, and efficient heat management is achieved. Connection with a mobile terminal or computer equipment in a wired or wireless mode is supported, and remote control over the operation state of the laser is achieved. The device is compact in structure, efficient in heat dissipation and convenient to carry, has good heat dissipation performance, independent power supply capacity and environmental adaptability, is suitable for application scenes such as multi-scene field operation and emergency use, and has good practicability and popularization value.

The invention discloses a welded joint treatment method based on laser remelting and ultrasonic shot peening synergistic strengthening, and relates to the technical field of additive manufacturing. An optical fiber laser is adopted for conducting remelting treatment on the welding seam, the laser power ranges from 800 W to 1500 W, the scanning speed ranges from 0.5 m / min to 2 m / min, the light spot diameter ranges from 0.5 mm to 2 mm, microdefects are eliminated, and grains are refined; and then surface impact strengthening is conducted on the remelting area through ultrasonic shot peening equipment, the diameter of a shot ranges from 0.8 mm to 2 mm, the frequency ranges from 20 kHz to 40 kHz, the amplitude ranges from 30 micrometers to 80 micrometers, and a gradient pressure stress layer is formed. According to the method, through the alternating effect of ultra-fast laser low-heat input remelting and gradient particle size bullet impact, a nanocrystalline layer is formed on the surface layer of the material, the microhardness is improved, meanwhile, an ultra-fine grain structure is reserved in a transition area, gradient performance matching of hard outside and tough inside is achieved, and the method is particularly suitable for high-performance manufacturing of high-strength aluminum alloy (such as 7075-T6 and 2024-T3) welding components for aerospace.

A first pumping source and a second pumping source are combined through a pumping beam combiner and are coupled into an erbium-doped fluoride fiber and a high-reflectivity fiber bragg grating, and the erbium-doped fluoride fiber and a low-reflectivity fiber bragg grating form a laser resonant cavity. The intermediate infrared laser is output through the low-reflectivity fiber bragg grating, the cladding light filter and the optical fiber end cap; the high-reflectivity fiber bragg grating and the low-reflectivity fiber bragg grating have the same grating period, the fourth-order harmonic reflection wavelength of the grating is located in the emission spectrum range of transition of erbium ions from the 4F9 / 2 energy level to the 4I9 / 2 energy level, and the fifth-order harmonic reflection wavelength of the grating is located in the emission spectrum range of transition of erbium ions from the 4I11 / 2 energy level to the 4I13 / 2 energy level; by adjusting the power of the first pumping source and the second pumping source, the net gain of laser transitions from the 4F9 / 2 energy level to the 4I9 / 2 energy level and transitions from the 4I11 / 2 energy level to the 4I13 / 2 energy level is regulated and controlled, and switching of laser working wavelengths is achieved.

The invention provides a high-speed laser-induced breakdown spectral imaging device and method. The high-speed laser-induced breakdown spectral imaging device comprises an optical fiber laser, a marking table, a high-speed scanning galvanometer, a flat-field scanning lens, a dichroic spectroscope, a laser isolation head, a focusing lens, a high-speed spectrograph, a delay pulse generator, an electronic control card and a computer. The electronic control card is connected with the computer, the fiber laser, the high-speed scanning galvanometer and the delay pulse generator; the delay pulse generator is connected with the high-speed spectrometer; the high-speed spectrometer is connected with the computer; geometric centers of the high-speed scanning galvanometer, the dichroic spectroscope and the laser isolation head and a straight line where laser is located are on the same straight line; and a flat field scanning lens is arranged below the high-speed scanning galvanometer. By applying the technical scheme, the task of single-point laser emission sampling exceeding 10000 Hz and dot matrix data acquisition exceeding 2000 Hz can be completed.

The utility model discloses a thulium-doped fiber laser based on a composite cavity structure. The thulium-doped fiber laser comprises a pumping source, a thulium-doped gain active fiber, a high-reflectivity fiber grating HR, a first low-reflectivity fiber grating OC1 and a second low-reflectivity fiber grating OC2, the self-pulse effect is inhibited by adopting a composite resonant structure, so that stable 2-micron fiber laser output is obtained; the overall optical path length is short, and self-pulse suppression can be more effectively achieved under the condition that the overall optical path length is short.

The invention discloses a laser heat dissipation system and method and an air-cooled fiber laser, and relates to the technical field of lasers, the disclosed laser heat dissipation system comprises a data acquisition module, a main control module, a fan driving module and a heat dissipation fan, the main control module is electrically connected with the data acquisition module and the fan driving module, and the fan driving module is electrically connected with the heat dissipation fan. The fan driving module is electrically connected with the cooling fan; the data acquisition module is used for acquiring the output power, the input current, the input voltage and the temperature value of the laser; the main control module is used for determining a reference fan control signal according to the output power and correcting the reference fan control signal according to the temperature value and / or an efficiency value calculated through the output power, the input voltage and the input current to obtain a target fan control signal; and the fan driving module is used for controlling the rotating speed of the cooling fan according to the target fan control signal. The heat dissipation efficiency of the laser heat dissipation system can be improved.

The invention provides an atypical MOPA fiber laser device integration device, system and method. The device comprises an optical resonant cavity, a first device group and a second device group, wherein the first device group comprises a first amplification stage gain optical fiber, a first reverse pumping beam combiner, a first pumping source and a first cladding light stripper, and the second device group comprises a second amplification stage gain optical fiber, a second reverse pumping beam combiner, a second pumping source and a second cladding light stripper; the optical resonant cavity is used for receiving the pump light transmitted by the first amplification stage gain optical fiber and the second amplification stage gain optical fiber, transmitting the pump light which is not absorbed to the second amplification stage gain optical fiber and the first amplification stage gain optical fiber, and generating signal light under the action of the absorbed pump light; and the signal light is transmitted to the first amplification stage gain fiber and the second amplification stage gain fiber in positive and negative directions. The device number and the manufacturing cost are remarkably reduced, the light-to-light conversion efficiency and the system reliability are improved, and meanwhile high-power beam combination and miniaturization integration are facilitated.

The invention provides a handheld laser-electric arc double-heat-source welding gun and a control method thereof. The handheld laser-electric arc double-heat-source welding gun is composed of a handheld component, a light beam control component, a focusing transmission sleeve and an electric arc welding gun sleeve. A laser optical fiber and an argon arc welding water electric pipe are input through a handheld part, and the handheld part is cooled through cooling water and a protective gas channel in the handheld part; starting and stopping of the laser and electric arc double heat sources are synchronously controlled through a starting switch on the side face of the handheld component. A swing motor in the light beam control part is used for driving a reflecting mirror to reflect a laser beam to a focusing transmission sleeve, and the laser beam is focused by a focusing lens and then acts on a workpiece; the state of an electric arc welding straight copper pipe in the electric arc welding gun sleeve is adjusted, and the positions and angles of an electric arc welding gun head and a laser welding gun head are changed; through the water and electricity pipe, the protective gas pipe and the water return pipe, electric power supply, protective gas conveying and cooling circulation of electric arc welding are achieved; the method is used for achieving high-quality welding of medium and thick plates made of different materials.

The invention relates to the technical field of fiber laser cutting, in particular to a high-precision fiber laser metal plate cutting method and system, and the method comprises the following steps: obtaining an original capacitance value of a capacitive induction ring; the original capacitance value of the capacitive induction ring is separated into an average capacitance value and a high-frequency vibration signal; extracting a vibration amplitude from the high-frequency vibration signal; according to the non-linear relation between the capacitance value and the distance of the capacitive induction ring, the vibration amplitude and the average capacitance value, direct current deviation caused by high-frequency vibration is calculated; subtracting the direct current deviation from the average capacitance value to obtain a corrected average capacitance value; and controlling the distance between the nozzle and the metal plate according to the corrected average capacitance value. And the cutting quality and the size precision can be improved.

The invention provides an all-polarization-maintaining optical fiber mode-locked laser which comprises a linear cavity and an annular cavity. Wherein the annular cavity consists of a wavelength division multiplexer, an optical fiber coupler, a phase bias device, a gain optical fiber and a dispersion compensation optical fiber; the linear cavity is composed of an optical fiber coupler and an optical fiber reflector. As a function multiplexing device, an external electric field is applied to the phase bias device, so that the functions of continuous tuning of the phase difference in the positive direction and the negative direction in the annular cavity of the 9-shaped cavity mode-locked fiber laser and rapid phase tuning are realized, and the realization of a mode-locked state and a high-precision phase locking state is promoted. In addition, the composition structure of the resonant cavity can be simplified, and the repetition frequency and the system stability of the mode-locked laser can be improved. The technology for constructing the 9-shaped cavity mode-locked fiber laser by adopting the active phase bias device has originality in the field of ultrafast optics, and a better choice is provided for the all-polarization-maintaining fiber mode-locked laser.

The invention discloses a control method for robot-assisted laser in-situ windowing, which comprises the following steps: receiving an execution instruction sent by a main control end through a robot catheter system, sending a laser fiber into a target artery, and enabling the laser fiber to be in accurate contact with a stent covering film; a laser energy closed-loop control subsystem is combined to accurately ablate holes in a stent covering film through a photochemical effect and a photothermal effect, and laser windowing is achieved; in the laser windowing process, the thickness of the blood vessel wall is measured in real time based on optical coherence tomography, and the laser ablation process is detected based on photoacoustic monitoring, so that the laser power is dynamically adjusted, and it is ensured that the thermal damage range in the laser windowing process is smaller than 200 microns. Therefore, accurate creation of the channel between the aortic dissection false cavity and the true cavity is achieved, hemodynamic balance is recovered, the operation accuracy is improved, and the risk of complications in the perioperative period is reduced.

The invention discloses a programmable waveform modulation high-power optical fiber laser system, particularly relates to the field of high-power optical fiber lasers, and is used for solving the problem of power monitoring and control instability caused by alias distortion under high pulse repetition frequency. Micro-amplitude random time jitter is implanted, sampling and pulse rhythm coupling are scattered through synchronous mapping of a time mark and a power sequence, and turn-back pseudo fluctuation is blocked from the source; the abstract evaluation mechanism fuses energy domain and time domain features, and uses a single determination identifier to drive sampling frequency adaptive migration, so that a monitoring link is continuously in a co-prime fraction ratio operation interval, and alias distortion root causes are eliminated; the sampling label and the judgment identification jointly trigger a feed-forward gain matrix to form a monitoring evaluation adjustment compensation closed loop, power aftershock is reduced in real time, stimulated scattering and thermal lens linkage amplification are inhibited, and light beam quality stability and energy smooth distribution are maintained.

The utility model belongs to the technical field of fiber lasers, and particularly relates to a high-efficiency frequency doubling system for a laser. The high-efficiency frequency doubling system for the laser comprises a first lens, a first frequency doubling crystal, a 4f system and a second frequency doubling crystal which are arranged in sequence. According to the high-efficiency frequency doubling system for the laser, the two frequency doubling crystals are used, phase matching is adopted, S polarization light and P polarization light of fundamental frequency light are subjected to frequency doubling in sequence to form P polarization frequency doubling light and S polarization frequency doubling light, two times of frequency doubling of the non-polarization-maintaining fiber laser are achieved through two times of frequency doubling, and high-power green light in the mixed polarization direction is obtained. And under the condition that the infrared fundamental frequency power is kept unchanged, the proportion of S polarization component light to P polarization component light is changed due to the change of the polarization state, but two generated green light beams are complementary, so that the power output is more stable than that of one crystal.

The invention concerns an apparatus and its use for laser welding. A laser welding apparatus comprise at least one first laser device, each providing at least one first optical feed fiber with a first laser beam; at least one second laser device, each providing at least one second optical feed fiber with a second laser beam; means for generating a composite laser beam comprising a first output laser beam and a second output laser beam for welding a workpiece; wherein the first output laser beam has a circular cross-section and the second output laser beam has an annular shape concentric to the first output laser beam. The second laser device is a fiber laser device or a fiber-coupled laser device. The apparatus is configured to form the second output laser beam at least on the basis of the second laser beam, and the second output laser beam comprises a first wavelength and a second wavelength having difference of at least 10 nanometers, or the second output laser beam has spectrum width of least 10 nanometers.

The invention provides a fiber laser interference vibration measurement method and device, and relates to the technical field of fiber laser interference vibration measurement. The laser is divided into reference light and measuring light through the 1 * 2 coupler, the measuring light is divided into multiple paths through the 1 * N coupler, the multiple paths of light are irradiated to the same measuring point from multiple directions through the circulator and the collimation / focusing optical element, a redundant light return channel is constructed, and the light return success rate and interference stability under a rough surface or a curved surface or a diffuse reflection surface are effectively improved. The return light and the reference light are superposed in the interference unit to form interference fringe signals, high-precision vibration displacement data are extracted through signal detection and three-phase demodulation, and the method is suitable for non-contact vibration measurement scenes which are low in cost and easy to deploy.

The invention particularly relates to an excitation signal waveform intelligent optimization method for a high-power narrow-linewidth fiber laser, and the method comprises the steps: obtaining an excitation signal, carrying out the processing of a phase modulation waveform of the excitation signal, and extracting an input feature set needed by frequency spectrum prediction; constructing a frequency spectrum prediction model based on the decoupling echo state network, inputting the input features into the frequency spectrum prediction model based on the decoupling echo state network, realizing nonlinear mapping between the phase modulation waveform of the excitation signal and the frequency spectrum response thereof, and obtaining a prediction frequency spectrum; constructing a composite cost function including a mean square error, a spectrum sideband leakage penalty term and a spectrum smoothing term based on the difference between the predicted spectrum and the target spectrum; based on a composite cost function, an Adam optimization algorithm is adopted to iteratively correct a phase waveform in a frequency domain, intelligent waveform optimization of phase modulation is realized, and a threshold value of a stimulated Brillouin scattering effect is reduced. The intelligent optimization of the phase modulation waveform of the excitation signal can be realized.

The invention discloses an SLM (selective laser melting) forming method of an In718 high-temperature alloy material, which comprises the following steps: selecting 15-35 mu m spherical powder, and carrying out ultrasonic screening, plasma activation and 50-100nm aluminum oxide coating modification to improve wettability and oxidation resistance; in an inert gas cabin, a platform is preheated at the temperature of 100-150 DEG C, and a pre-tightening layer with the density larger than or equal to 98% is formed through vibration auxiliary powder laying; a pulse fiber laser is adopted to dynamically modulate parameters, a thin-wall area and a solid area are matched with a spiral scanning path, and the cooling rate of a molten pool is reduced by 30%-50%; a molten pool is monitored through dual-wavelength infrared temperature measurement and a high-speed CCD, and laser frequency compensation and argon blowing stable convection are triggered; constructing a three-layer temperature gradient; by means of the method, the density and the high-temperature performance of the formed part are improved, and the method is suitable for manufacturing of aerospace complex structural parts.

The invention discloses a micro-droplet long-distance optical force traction system based on a nanometer optical fiber. The system comprises an optical fiber laser, a nano optical fiber, micro-droplets, an imaging optical element and an imaging camera, the nanometer optical fiber comprises a first optical fiber non-tapering area, a second optical fiber non-tapering area, a first optical fiber taper area, a second optical fiber taper area and a uniform waist area located in the middle. And the micro-droplets coat the uniform waist region of the nano optical fiber. The transmission loss of the nanometer optical fiber is low, the total length can reach the meter level, a transmission light field in the uniform waist area of the nanometer optical fiber interacts with the micro-droplets, forward scattering is enhanced through momentum exchange, and therefore long-range optical traction force is applied to the micro-droplets. According to the invention, the problem of short luminous traction action distance (millimeter level) based on a single light beam in the prior art is solved, and the device has the advantages of long-distance control (centimeter to meter level), high precision, high flexibility, good stability and good biocompatibility, and can be applied to the biochemical fields of cell control and sorting, biological detection, micro-droplet reaction and the like.

The invention provides a dual-mode resonance optical fiber microcavity air pressure measurement system and method, and relates to the technical field of optical fiber microcavity air pressure measurement, and the system specifically comprises a sensing probe preparation module, a two-parameter sensitivity matrix calibration module, an optical fiber laser sensing system construction module, a real-time change monitoring module and a decoupling and output module. Femtosecond laser etching is combined with high-temperature tapering, an open type microcavity is manufactured on a single-mode optical fiber, a micro-nano cone area is formed, and the sensing probe with two resonance valleys with different temperature and air pressure response characteristics is obtained. A sensitivity coefficient matrix is obtained through calibration, a probe serves as a filter to be embedded into an annular optical fiber laser cavity, and an optical fiber laser with the laser wavelength locked by a resonance valley is constructed. Laser wavelength drift is caused by environmental change, real-time synchronous measurement of temperature and air pressure is realized by utilizing inverse matrix decoupling, and the method is suitable for high-precision and anti-interference monitoring of harsh industrial environments such as aero-engines and power transformers.

The invention relates to the technical field of optical signal transmission, in particular to an optical fiber polarization measurement system and method. The optical fiber polarization measurement system comprises a light source which is located at the light incident side of a to-be-measured optical fiber and is used for inputting detection laser to the to-be-measured optical fiber; the optical fiber temperature control assembly is circumferentially arranged along the periphery of the to-be-measured optical fiber and is used for adjusting the temperature of the to-be-measured optical fiber; the light-emitting optical fiber is the same as the optical fiber to be detected in model and is welded with the output end of the optical fiber to be detected through polarization-maintaining welding; the heat preservation rotating assembly is arranged close to the output end of the light-emitting optical fiber and used for providing a constant-temperature environment for the light-emitting optical fiber and driving the light-emitting optical fiber to rotate concentrically. The polarization analyzing assembly is located at the output end of the light-emitting optical fiber and used for screening the output laser output by the light-emitting optical fiber based on the polarization direction; the photoelectric detection assembly is located on the side, away from the light outlet optical fiber, of the polarization detection assembly and used for detecting the optical power of the polarized laser screened by the polarization detection assembly. The measuring efficiency can be effectively improved, the cost is reduced, and the structure is simplified.