2255 results about "Laser fiber" patented technology

The invention relates to the technical field of laser control, in particular to a high-power fiber laser stable output control method and system. The method comprises the following steps: monitoring a multi-mode sensing signal of an optical fiber laser in real time based on an optical fiber sensor array; performing dynamic optical fiber sensing change analysis on the multi-mode sensing signal of the optical fiber laser to generate a dynamic optical fiber sensing change characteristic; laser output phase distribution analysis is carried out on the dynamic optical fiber sensing change characteristics, real-time power feedback adjustment is carried out, and a dynamic light beam power feedback adjustment strategy is constructed; overheat power unbalance analysis is carried out based on a fiber laser multi-mode sensing signal, and local temperature control power fine tuning is carried out, so that a local temperature control power fine tuning strategy is constructed; and performing sensor position calculation on the optical fiber sensor array one by one, and performing nonlinear optical effect analysis to generate nonlinear optical effect characteristics. According to the invention, efficient and stable laser output control is realized.

The invention discloses a high-precision photoacoustic spectrum monitoring method for gas in transformer oil, and relates to the technical field of transformer oil gas monitoring, and the method comprises the following steps: constructing a photoacoustic spectrum detection system, sampling the gas in the transformer oil, and obtaining photoacoustic spectrum data of the gas, the photoacoustic spectrum detection system comprises a near-infrared tunable fiber laser, a photoacoustic cell, a lock-in amplifier and a data acquisition system; preprocessing the acquired photoacoustic spectrum data, and extracting features related to fault diagnosis from the preprocessed photoacoustic spectrum data; and the photoacoustic spectroscopic data of the mixed gas is decoupled by using a chemometrics method. According to the method, the gas photoacoustic spectroscopic data in the transformer oil are collected and analyzed in real time, abnormal conditions in the transformer are found as soon as possible, the mixed gas spectroscopic data are decoupled and separated in combination with chemometrics and a machine learning algorithm, and various gas components are accurately recognized and quantitatively analyzed.

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 belongs to the technical field of lasers, and discloses a 9-shaped hybrid mode-locked fiber laser, which comprises a pumping source, a 2 * 2 polarization-maintaining fiber coupler, a nonlinear amplification loop mirror loop connected with the first side of the polarization-maintaining fiber coupler, and a chirp fiber Bragg grating connected with the second side of the polarization-maintaining fiber coupler, the polarization maintaining optical fiber coupler is located at the connecting position of the nonlinear amplification annular mirror loop and a linear arm of the laser resonant cavity and used for coupling laser of the nonlinear amplification annular mirror loop to the linear arm, and after being reflected by the chirp fiber bragg grating, the laser is output to the nonlinear amplification annular mirror loop through the chirp fiber bragg grating. And then the laser on the linear arm is split into two beams of light which are transmitted clockwise and anticlockwise in a loop of the nonlinear amplification annular mirror. Two passive mode locking technologies are combined, rapid and stable mode locking can be achieved, the influence of the environment on the operation state is small, the signal-to-noise ratio of output laser pulses can be increased, and ultra-short pulses with narrower pulse width can be achieved.

The invention provides an ultra-pulse thulium fiber laser therapy apparatus which comprises a laser, an electrical device and a coupler, the laser is connected with the coupler through a thulium fiber, the laser and the coupler are respectively connected with the electrical device through circuits, and the electrical device is connected with the coupler through a thulium fiber. The electrical device controls the operation of the laser and the coupler, the optical fiber is a thulium optical fiber emitted by the laser, and the wavelength of the laser is 1940 nanometers. The ultra-pulse thulium fiber laser therapy apparatus replaces a previous water cooling device and adopts a 1940nm laser internal air cooling device, so that the ultra-pulse thulium fiber laser therapy apparatus is more compact in structure, lighter in weight and smaller in size, and the problems of noise, frequent maintenance and replacement and the like caused by a large cooling-water machine are solved.

The invention provides an intelligent regulation and control system for wavelength and power data of a multi-wavelength tunable ultrafast fiber laser, and relates to the technical field of data processing, and the method comprises a data collection module which is used for obtaining the wavelength data and the power data of the multi-wavelength tunable ultrafast fiber laser in real time; the data processing module is used for receiving and processing the obtained wavelength data and power data, and performing data analysis, filtering and abnormal value detection to obtain a data analysis result; the intelligent regulation and control module is used for automatically adjusting parameters of the multi-wavelength tunable ultrafast fiber laser according to the data processing and analysis result so as to regulate and control the wavelength and the power; and the data management module is used for storing the obtained wavelength data, power data and related data in the regulation and control process. According to the invention, the wavelength and power of the multi-wavelength tunable ultrafast fiber laser are efficiently, intelligently and remotely regulated and controlled, the system performance is self-optimized, and the regulation and control precision, the response speed and the system stability of the laser are improved.

The invention provides a high-power multimode fiber laser amplifier based on wavefront shaping. The high-power multimode fiber laser amplifier comprises a seed light wavefront control unit, a multimode gain fiber amplification unit and an output light spot detection and feedback unit, the seed light wavefront control unit is used for carrying out wavefront modulation on the seed light output by the polarization seed laser by using a spatial light modulator loaded with a phase diagram; the multimode gain optical fiber amplification unit is used for performing power amplification on the seed light which is output by the seed light wavefront control system and is subjected to output wavefront modulation; and the output light spot detection and feedback unit is used for outputting the laser of most power of the multimode gain fiber amplification system, collecting the rest laser of a small part of power for far-field light spot information detection, calculating the corresponding far-field barrel medium power based on the detected far-field light spot information, and outputting the far-field barrel medium power. And the power in the far-field barrel is used as an evaluation function to operate an optimization algorithm to generate an optimal phase diagram, and the optimal phase diagram is loaded on the spatial light modulator to realize closed-loop feedback control.

The invention belongs to the technical field of optical fiber laser welding, and particularly relates to optical fiber laser welding equipment which comprises a rack, a conveying mechanism used for conveying a battery module is arranged in the rack, an XYZ-axis moving mechanism is installed on one side of the rack, a laser welding device is installed on the XYZ-axis moving mechanism, and a conveying belt is connected to one side of the end of the rack. The conveying mechanism comprises two sets of transmission shafts, the two sets of transmission shafts are rotationally installed in the rack, chain wheels are installed on the two sets of transmission shafts, the two sets of chain wheels are meshed with a chain, a plurality of sets of shifting forks used for containing battery modules are arranged around the chain, and one ends of the shifting forks are fixedly connected with the chain. According to the battery module welding device, feeding, welding and discharging of the battery module can be conducted at the same time, the automation rate of the device is increased, meanwhile, the battery module can be continuously welded, and the welding efficiency of the battery module is improved.

An article of manufacture including a fiber optic termination of a small core optical fiber for use with a surgical laser apparatus (the output from which may be characterized by a high M2 factor) or other high-power or high-energy laser (including an appropriate fiber laser) is configured for safe and efficient coupling of light at a large laser focal point and / or to enable the process of coupling of radiant intensities exceeding the silica fiber damage thresholds and / or those ionizing the air if fully focused therein. The termination may include a glass cylinder structured to include a core region and a glass cladding region the ratio of dimensions of which is substantially equal to the ratio of respectively-corresponding dimensions of the employed optical fiber. A method of propagating light through such article of manufacture.

The invention discloses a 2 [mu] m nanosecond pulse fiber laser and a time domain waveform adjustment method thereof. The laser comprises a seed source module and an amplification module connected with the seed source module. The seed source module comprises a first high-reflectivity fiber bragg grating, an acoustic optical modulator, a first beam combiner, a first thulium-doped fiber, a 2 * 2 coupler and a second high-reflectivity fiber bragg grating which are connected in sequence, as well as a driving source connected with the acoustic optical modulator and a first pumping source connected with the first beam combiner; the amplification module comprises an online isolator, a second beam combiner, a second thulium-doped optical fiber and an output jumper which are connected in sequence, and a second pumping source connected with the second beam combiner; the rising edge time and the starting time of the acousto-optic modulator are subjected to parameter setting through a human-computer interface of the driving source; the wavelengths of lasers output by the first pumping source and the second pumping source are both 793 nanometers. According to the invention, the multi-peak phenomenon of the Q-switched pulse laser of the 2um waveband can be conveniently and effectively eliminated, the performance of the laser is improved, and the application requirements of low cost and mass production are met.

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 discloses a high-power intermediate infrared fiber laser. The fiber laser is composed of a first pumping source, a second pumping source, a pumping beam combiner, a high-reflectivity fiber grating, a low erbium-doped fluoride fiber, a low-reflectivity fiber grating, a cladding light filter, a fiber end cap, a collimating lens and a dichroscope. The mode of combining erbium ion ground state transition achieved through fiber core pumping and erbium ion excited state transition achieved through cladding pumping is adopted, mid-infrared laser upper energy level particle number accumulation is obtained, and meanwhile laser lower energy level particles are effectively consumed through the cladding pumping transition process. And the population inversion state of the laser system is kept, and the particle circulation rate and the quantum efficiency from the pump light to the intermediate infrared laser are improved, so that the generation of high-power and high-efficiency intermediate infrared fiber laser is realized.

The invention provides a downlink data transmission method, device and system for laser fiber power supply application, and the method comprises the steps: carrying out the differential coding of downlink data to be transmitted through a transmitting end, and obtaining a data bit sequence; mapping the data bit sequence into a modulation symbol sequence by adopting a single-carrier phase modulation mode; performing digital-to-analog conversion on the modulation symbol sequence to obtain an analog signal; and outputting downlink energy and downlink data through an energy optical fiber according to the analog signal. According to the invention, the signal frequency spectrum is moved to be far away from the direct current frequency through differential coding and single carrier phase modulation, so that the interference of direct current laser energy on signal detection is minimized, the signal-to-noise ratio is improved, the inter-symbol interference is reduced, and a receiving end is ensured to have enough signal-to-noise ratio to reliably detect data.

The utility model provides an air pressure control device for optical fiber laser cutting, which belongs to the technical field of optical fiber laser cutting and comprises a cutting platform fixedly connected with a support frame; the air injection adjusting assembly comprises an annular plate rotationally connected to the top of the supporting frame through an annular bearing, an adapter bracket is fixedly connected to the outer wall of the annular plate, an air pump is fixedly connected to the adapter bracket, an air nozzle is arranged at the lower end of the air pump, and a rotation driving component is arranged at the top of the supporting frame. The air injection angle of the air nozzle can be rapidly adjusted, residual cutting materials can be fully removed, the follow-up cleaning work cost can be reduced, the air injection pressure can be automatically adjusted to adapt to the cutting depth of the materials, the cutting materials in a deep cutting groove can be completely discharged, and the cutting efficiency is improved. And the cutting processing quality of the material is ensured.

The utility model provides a low-reflection light-splitting monitoring fiber laser which comprises a fiber amplifier, a light-splitting isolation assembly, an output head and a photoelectric detector. The light splitting isolation assembly comprises a double-fiber collimator, a two-stage isolator and a single-fiber collimator which are sequentially arranged in the direction of a main light path, the double-fiber collimator comprises a first optical fiber, a second optical fiber, a first capillary tube and a first lens, and the fiber core end of the first optical fiber and the output end face of the first capillary tube form a first beam expanding length; the fiber core end of the second optical fiber and the input end face of the second capillary tube form a second beam expanding length, the input end of the first optical fiber is connected with the optical fiber amplifier, the output end face of the first lens faces the input end of the two-stage isolator, the output end face of the first lens is plated with an anti-reflection film, and the output end of the second optical fiber is connected with the photoelectric detector. According to the scheme, the optical path is more concise, a device optical fiber coupler is saved, more space is reserved, and the integration level of the laser module is higher.

According to the multi-beam confocal mask defect detection system and method based on the fiber laser array, a multi-point scanning light field is obtained on the basis of the fiber laser array to serve as an illumination light source, the scanning light field can be regulated and controlled on the basis of arrangement of the laser array, and through the combined action of a motion table and a multi-face rotating mirror, the defect of the multi-beam confocal mask is detected. Rapid and accurate mask two-dimensional scanning imaging is achieved, and high-resolution detection of mask defects is achieved on the basis of a confocal microscopic imaging method in cooperation with a high-power microscope objective and a photomultiplier. Compared with a traditional point scanning type mask defect detection system, the system has the advantages that the detection resolution is high, the scanning speed is high, a multi-point scanning light field can be freely regulated and controlled, and no extra diffraction optical element needs to be introduced.

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 relates to a single-photon laser radar three-dimensional imaging system and method. An optical fiber laser is used for actively illuminating an imaging target; the single-photon APD array detector is used for receiving a laser echo signal reflected by a target; the near-infrared detector is used for realizing aiming; the upper computer is used for parameter setting and data receiving of the optical fiber laser, the single-photon APD array detector and the near-infrared detector, receiving active laser three-dimensional imaging data in a three-dimensional imaging state and realizing real-time display of a depth image and an intensity image; and the information processing board card is used for realizing synchronous triggering of the fiber laser and the single-photon APD array detector and data communication between the upper computer and the fiber laser and the single-photon APD array detector, and realizing preprocessing and three-dimensional reconstruction of APD data based on a time correlation single-photon counting method and in combination with space-time correlation characteristics of laser echo signals. According to the invention, the problem of insufficient detection capability of a single-photon laser three-dimensional imaging method under all-weather and low-signal-to-noise-ratio conditions is solved.

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 a self-adaptive wide-temperature-interval air-cooled fiber laser and a control method, the self-adaptive wide-temperature-interval air-cooled fiber laser comprises a shell, a first pumping module, a second pumping module, a control module, a first current driving module and a second current driving module are arranged in the shell, the first current driving module is connected with the first pumping module, and the second current driving module is connected with the second pumping module. The first current driving module is connected with the first pumping module, the second current driving module is connected with the second pumping module, a laser gain cavity is formed in the side face of the shell, a first fan and a second fan are arranged on one side of the shell, a first air cooling heat dissipation plate and a second air cooling heat dissipation plate are arranged on the other side of the shell, and the laser gain cavity is connected with the first pumping module and the second pumping module. The first fan, the second fan, the first pumping module, the second pumping module, the first current driving module and the second current driving module are all connected with the control module, and the laser gain cavity is connected with an optical fiber cladding light filter. By controlling the temperature environment, the pump light conversion rate is increased.

A high-brightness and high-power fiber laser adopts an oscillator structure and comprises a pumping module, a high-reflectivity fiber grating, a gain fiber, a low-reflectivity fiber grating and a cladding light filter, the gain fiber is a rare earth ion doped ZBLAN fiber which takes ZBLAN as a matrix material and is of an all-solid-state anti-resonance structure, and the low-reflectivity fiber grating is a rare earth ion doped ZBLAN fiber which is of an all-solid-state anti-resonance structure. The gain optical fiber comprises a fiber core area, a cladding area, an anti-resonance area and a coating layer, the anti-resonance area is composed of at least one capillary tube set, each capillary tube set comprises a plurality of capillary tubes, the capillary tubes in each capillary tube set are annularly arranged on the periphery of the fiber core area with the fiber core area as the center, and the cladding layer is arranged on the cladding layer. The matrix material in each capillary tube and the matrix material in the cladding region are the same and are ZBLAN, and the matrix material ZBLAN in the fiber core region is doped with dysprosium ions. According to the invention, the rare earth doped all-solid-state anti-resonance optical fiber is adopted as the gain optical fiber, so that high-brightness, high-power and high-efficiency output can be realized.

A 2-micron large-energy solid two-way amplifier based on a single-frequency pulse optical fiber preceding stage can make full use of the small signal amplification capacity of optical fiber laser and the energy extraction capacity of solid laser, and meanwhile the problem that energy is difficult to improve due to the stimulated Brillouin scattering effect in an optical fiber is solved. And high-stability, high-repetition-frequency and large-energy single-frequency pulse laser output can be realized. The all-fiber cascade amplifier comprises an all-fiber cascade amplifier and a solid two-way amplifier, according to the all-fiber cascade amplifier, a continuous narrow-linewidth fiber laser is adopted as a seed source, continuous light is modulated into pulse light through an acousto-optic modulator, and the waveform, the pulse width and the repetition frequency of output pulse laser are adjusted; the modulated pulse light adopts a main oscillation power amplification structure and is preliminarily amplified by a polarization maintaining optical fiber amplifier; the solid-state amplifier adopts a two-way amplification structure, and further high-efficiency amplification is realized through solid-state two-way amplification. The whole laser system is compact in structure, stable, adjustable in parameter and capable of meeting application requirements of different scenes.

The invention relates to a power correction method of an optical fiber laser, which comprises the following steps of: setting output power of the laser, and obtaining a power simulation curve; the laser is operated, N measured values of the output power of the laser are obtained, a power sampling curve is generated, and N is larger than or equal to 10; acquiring a power difference value between the power simulation curve and the power sampling curve; acquiring the compensation gain of the output power according to the power difference value; selecting a compensation mode according to the compensation gain; and correcting the working condition of the fiber laser according to the selected compensation mode so as to correct the output power of the fiber laser and reduce the error between the set power and the actual output power. Before long-term operation of the fiber laser, the deviation of the output power can be accurately identified, the working condition of the laser is correspondingly adjusted according to the compensation gain calculated by the power difference value, the method is executed regularly or as required, and the power of the fiber laser is stable after correction. The output power fluctuation caused by the influence of real-time factors such as return light and pump light in the optical fiber is avoided, and the method can correct the power of the optical fiber laser more accurately, stably and reliably.

The embodiment of the invention discloses an optical fiber laser and a green laser device. The fiber laser comprises a seed source and at least one stage of fiber amplifier. The seed source comprises a first pumping source, a first pumping beam combiner, a first fiber bragg grating, a first ytterbium-doped fiber, a second fiber bragg grating and a second ytterbium-doped fiber; the optical fiber amplifier comprises a second pumping source, a second pumping beam combiner and a third ytterbium-doped optical fiber; the second pumping source comprises a third pumping source, a third pumping beam combiner, a third fiber bragg grating, a fourth ytterbium-doped fiber and a fourth fiber bragg grating. The optical fiber laser provided by the embodiment of the invention adopts a cascade pumping technology, so that the power and brightness of fundamental frequency laser output by the narrow linewidth optical fiber laser are effectively improved, the nonlinear effect of the fundamental frequency laser and the thermal load of the optical fiber are remarkably reduced, and the beam quality and output power of the fundamental frequency laser are remarkably improved; and a foundation is laid for higher green light output.

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.

Systems, devices, and methods for providing adjustable laser treatment of a target using fiber-to-target distance measurements are disclosed. An exemplary surgical laser system includes a laser system to generate and deliver laser pulses to an anatomical target via an optical fiber, a feedback analyzer circuit to receive a return laser signal in response to a chirped laser irradiating at the target, and a controller circuit. The feedback analyzer circuit can generate an optical coherence metric using the chirped laser and the return laser signal, and determine a fiber-to-target distance between a distal end of the optical fiber and the target. Based at least on the fiber-to-target distance, the controller circuit can adjust a position or an orientation of the distal end of the optical fiber, or adjust a surgical laser output setting for generating and delivering laser pulses to the target.

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 laser multi-point focusing beam splitting auxiliary sintering method for a crystalline silicon battery piece. The method comprises the following steps: emitting a laser beam by adopting a continuous fiber laser; a light beam collimator is adopted to collimate and expand the laser beam; segmenting the collimated or low-emission laser beam into a plurality of laser beams in a lossless manner by using a lossless spectroscope; a plurality of laser beams sequentially pass through the high-speed scanning galvanometer and the field lens to form a multi-light-spot pattern, and the multi-light-spot pattern completes scanning processing on a fine grid on the front side of the crystalline silicon battery piece. The multi-spot pattern completes scanning processing on the fine grid on the front surface of the crystalline silicon cell piece, so that the laser processing scanning time on the front surface of the crystalline silicon cell piece can be shortened, and meanwhile, unbalanced carrier generation and collection are improved to reduce the contact resistance of a metal electrode. In addition, the whole surface of the cell does not need to be processed, the sintering time is shortened, and the laser-assisted sintering processing efficiency is improved.

A system for preventing inadvertent actuation of a medical device. The system includes an elongate tube having a proximal end, a distal end, and a lumen extending from the proximal end to the distal end. The lumen is configured to receive a medical device configured to transition between an actuated state and an inactive state. The device further includes a detection system configured to determine a position of a distal end of the medical device relative to the distal end of the elongate tube. The detection system includes a transmitting element and a receiving element.

The invention relates to a laser surface remelting method for improving corrosion resistance of a low-alloy steel weld joint, and belongs to the technical field of metal surface treatment and protection. The method comprises the following steps: (1) preparing a low-alloy steel welding seam by adopting gas metal arc welding; (2) polishing the low-alloy steel welding seam, immersing the welding seam in a treating fluid, and carrying out ultrasonic treatment, cleaning and drying to obtain the treated low-alloy steel welding seam; and (3) carrying out laser surface remelting treatment on the surface of the treated low-alloy steel welding seam by adopting an optical fiber laser. The laser surface remelting technology is simple in process, the influence of oxides and impurities on the surface of the welding seam on the quality of the welding seam is reduced through layer-by-layer treatment, efficiency is high, pollution is avoided, and the corrosion resistance of the low-alloy steel welding seam obtained through treatment is effectively improved.