176 results about "Nanosecond pulse" patented technology

The invention belongs to the field of laser processing and numerical simulation, and particularly relates to a finite element modeling and analysis method for a nanosecond pulse laser target material. The method comprises the following steps: establishing and loading a laser heat source model; establishing a target material finite element model and carrying out grid division; establishing and solving a transient heat conduction equation; carrying out multi-cycle iterative solution and post-processing; and performing model verification and parameter analysis. According to the method, the laser heat source model is established, the adaptive grid encryption strategy for temperature gradient optimization is adopted, and the transient solution algorithm is combined, so that compared with a traditional simplified analysis model or general commercial software simulation, the prediction precision of the target material temperature field spatio-temporal evolution law under the nanosecond pulse laser effect is remarkably improved. The method can accurately predict the temperature distribution and evolution law of the target material under the action of laser, has the advantages of high modeling precision, good calculation efficiency, wide application range and the like, and is suitable for engineering applications such as laser processing and damage evaluation of optical materials and composite materials.

A fractional handpiece and systems thereof for skin treatment include a passively Q-switched laser assembly operatively connected to a pump laser source to receive a pump laser beam having a first wavelength and a beam-splitting assembly operable to scan a solid beam emitted by the passively Q-switched laser assembly and form an array of micro-beams across a segment of skin. The passively Q-switched laser assembly generates a sub-nanosecond pulsed laser beam having a second wavelength. The fractional handpiece may also incorporate a wavelength switching assembly, enabling selective delivery of both the second and third wavelengths, while providing control over the energy output at each wavelength, all within a single handpiece. The passively Q-switched laser assembly has an unstable cavity operation.

A fractional handpiece and systems thereof for skin treatment include a passively Q-switched laser assembly operatively connected to a pump laser source to receive a pump laser beam having a first wavelength and a beam-splitting assembly operable to scan a solid beam emitted by the passively Q-switched laser assembly and form an array of micro-beams across a segment of skin. The passively Q-switched laser assembly generates a sub-nanosecond pulsed laser beam having a second wavelength. The fractional handpiece may also incorporate a wavelength switching assembly, enabling selective delivery of both the second and third wavelengths, while providing control over the energy output at each wavelength, all within a single handpiece. The passively Q-switched laser assembly has an unstable cavity operation.

The invention discloses a device and system for conducting electric field treatment on the digestive tract, the device for conducting electric field treatment on the digestive tract comprises a slender catheter, a supporting body located at the far end of the catheter, an electrode array film and a pulse generator, the electrode array film and the pulse generator are arranged on the supporting body, and the output end of the pulse generator is coupled with an electrode pair on the electrode array film. A sequence pulse wave output by the pulse generator comprises a plurality of groups of nanosecond pulse strings, and the time interval between the adjacent nanosecond pulse strings is 1us-10000 us; the nanosecond pulse string is composed of a plurality of nanosecond pulse pairs, and the time interval between every two adjacent nanosecond pulse pairs ranges from 50 ns to 10000 ns; the nanosecond pulse pair comprises positive pulses and negative pulses which appear alternately, the pulse width of the positive pulses and the pulse width of the negative pulses are 10-1000 ns, and the time interval is 10-1000 ns. The cell membrane permeability and the cell death efficiency can be remarkably improved, and the limitation of the traditional IRE technology is broken through.

The invention provides an optical neural network computing system and method based on time domain excitation characteristics, and the system comprises a pulse clock sequence module which is used for generating a reference time sequence; the multi-channel pulse laser array is used for generating semiconductor neuron laser pulses with subnanosecond pulse width based on a reference time sequence; the time domain and wavelength division multiplexing module is used for simultaneously performing time domain coding and wavelength division multiplexing on the laser pulse based on a reference time sequence to generate a first optical signal; the reconfigurable weight matrix module is used for performing all-optical linear matrix operation and weight mapping on the first optical signal to obtain a second optical signal; the neuron activation module is used for performing nonlinear activation processing on the second optical signal based on an LIF theory to obtain an activated optical signal; and the output module is used for carrying out decoding and photoelectric conversion on the activated optical signal to obtain a network reasoning result.

The invention relates to a single-objective isotropic three-dimensional super-resolution imaging method, which comprises the following steps of: outputting a linear polarization excitation light beam through a picosecond pulse laser, and outputting a linear polarization loss light beam through a nanosecond pulse laser, adjusting the polarization direction and power of the excitation light beam and the loss light beam by using a half-wave plate and a polarization beam splitter, enabling the loss light beam to enter a spatial light modulator, modulating a light field by loading a preset phase diagram, generating three focuses with different topological charges, axial positions and energy distribution, and outputting the three focuses. The high-order vortex phase retarder is used for carrying out polarization state modulation on the focus and separating loss light beams with different polarization components, the imaging resolution ratio smaller than 100 nm in the transverse direction and the axial direction is achieved, the transverse resolution ratio is similar to the axial resolution ratio, the three-dimensional real structure of an object can be accurately reflected when three-dimensional super-resolution imaging is carried out, and the imaging precision is improved. The imaging resolution is in direct proportion to the loss light intensity, and the higher the loss light intensity is, the higher the three-dimensional imaging resolution is.

The invention discloses a multi-objective optimization design method for a high-voltage nanosecond pulse adder, and aims to solve the problem that the prior art depends on experience trial and error and is difficult to consider multiple objectives such as fast leading edge, high efficiency, portability and reliability. The method comprises the following steps: firstly, building a simulation and experiment platform, and acquiring output waveform data for changing topological parameters; constructing a physical model of the influence rule of the parasitic parameters on the pulse rising edge time and the voltage gain, and establishing a power supply efficiency prediction model based on a deep neural network; taking the minimization of the pulse rising edge time and the maximization of the voltage gain and the energy efficiency as targets, constructing a particle swarm optimization multi-target optimization model in combination with the model, and obtaining a Pareto optimal solution set under the constraints of portability and parasitic parameters; and finally, carrying out experimental verification iteration to obtain an optimal scheme. According to the invention, the design period is obviously shortened, the multi-target conflict is effectively balanced, the rising edge time is shortened, the energy efficiency is improved, the voltage gain is improved, the portability is enhanced through the modular design, and the wearable application is compatible.

The application relates to a wideband high-power microwave protection module design method based on field line coupling, and belongs to the technical field of circuit simulation. The method comprises the following four steps: testing the response of a protection device under a nanosecond pulse; constructing an equivalent circuit model of a pulse source and the protection device; designing a protection module and simulating the characteristics of the protection module through a field line coupling method; and optimizing the protection module. The application has the following advantages: the field line coupling characteristics are considered, a protection module protection performance verification model is constructed, a cable coupling interference waveform is used to verify the protection performance of the protection module, and the accuracy of the protection performance simulation of the protection module is improved.

We present a ground-based laser system for searching, ranging, and tracking that actively illuminates small resident space objects (RSOs) in low Earth orbit (LEO) and observes position and transit-time of reflections, enabling orbital custody of most one-to-few centimeter-sized objects. A diode-pumped alkali laser (DPAL) augmented with mode-locking and Q-switching serves as an illuminator and offers exceptionally high spectral brightness due to its output beam's sub-nanosecond pulse duration and picometer-level spectral linewidth. Kilohertz fast-rastering enables interrogations of distinct few-meter-sized sky-patches at megahertz rates. Paired on the observation side with one or more telescopes outfitted with Faraday anomalous dispersion optical filters (FADOFs), image intensifiers, multi-pixel arrays, and nanosecond timing, the combined system could offer nearly background-free discoveries of RSOs every hour, even during daytime. Periodically re-flashing previously discovered objects to maintain orbit custody expends only a small fraction of total observing time.

The present disclosure provides a real-time holographic system and a real-time optical reconstruction method, which relate to the field of holographic technology. The system comprises: a first laser, adapted to generate nanosecond pulse light; a first beam splitter, adapted to split the nanosecond pulse light into reference light and detection light, the detection light being incident on an object to be measured and generating object light having information about the object to be measured; a reconstruction light timing module, adapted to generate reconstruction light having timed femtosecond pulse information; a dichroic mirror, adapted to generate combined light based on the incident reference light and reconstruction light; a holographic dry plate, adapted to receive the combined light and object light, so that the reference light and object light in the combined light interfere on the holographic dry plate to form a phase grating, thereby recording optical information; and a multi-frame imaging module, adapted to receive the reconstruction light and form a diffraction wave based on the phase grating, thereby reading the optical information with a time resolution of the order of picoseconds.

The application belongs to the technical field of precision laser processing, and specifically discloses a laser micro-drilling and cutting device and method for a metal foil lead frame, which comprises a processing platform, a clamp, a three-axis motion system, a scanning galvanometer and an ultraviolet nanosecond pulse laser. The clamp applies a pre-tension to the metal foil through a screw rod mechanism and integrates a laser displacement sensor to monitor thermal deformation in real time. The three-axis motion system and the scanning galvanometer cooperate to realize three-dimensional accurate positioning, and a reflection system dynamically regulated by multiple mirrors is combined to ensure that the laser is vertically incident. The method comprises clamping and focusing, image processing and path planning, multi-directional scanning processing and post-processing. The application solves the problems of thermal deformation suppression and micron-level feature accuracy maintenance in large-format processing through optical-mechanical coupling multi-axis linkage control, has the advantages of high precision, environmental protection and high efficiency, and is suitable for the preparation of ultra-thin metal foil lead frames.

Described herein are apparatuses and methods for applying high voltage, sub-microsecond (e.g., nanosecond range) pulsed output to a biological material, e.g., tissues, cells, etc., using a high voltage (e.g., MOSFET) gate driver circuit having a high voltage isolation and a low inductance. In particular, described herein are multi-core pulse transformers comprising independent transformer cores arranged in parallel on opposite sides of a substrate. The transformer cores may have coaxial primary and secondary windings. Also describe are pulse generators including multi-core pulse transformers arranged in parallel (e.g., on opposite sides of a PCB) to reduce MOSFET driver gate inductance.

The utility model discloses a nanosecond pulsed electric field ablation electric shock cup capable of adjusting the distance between electrode plates, which comprises a cup body and an electric shock cup cover, a pair of conductive aluminum electrode plates which are oppositely arranged are arranged at the lower part of the cup body, the electric shock cup cover is arranged on the cup body, the nanosecond pulsed electric field ablation electric shock cup also comprises a movable electrode plate which is adjustably arranged in the cup body, the movable electrode plate comprises an aluminum electrode plate body positioned at the lower part and a polycarbonate plate body positioned at the upper part; a high-voltage-resistant insulating rubber layer is adhered to the right side of the aluminum electrode plate body; the conductive aluminum electrode plate positioned on the left side and the left side of the aluminum electrode plate body are enclosed by a first telescopic insulating rubber sleeve to form a container with an upper opening and a variable space, and the container is used for accommodating a cell suspension; a high-voltage-resistant insulating rubber layer is adhered to the surface of the conductive aluminum electrode plate on the right side; the left side of the aluminum electrode plate body is electrically connected with the conductive aluminum electrode plate located on the right side through a wire.

The utility model relates to the technical field of medical equipment, and particularly discloses a bipolar nanosecond pulse synchronous output circuit and ablation equipment, which comprise a positive pulse output circuit and a negative pulse output circuit, the positive pulse output circuit comprises a positive pulse charging unit, a positive pulse output control unit, a positive pulse transmission unit and a positive pulse output electrode wire which are electrically connected in sequence; the negative pulse output circuit comprises a negative pulse charging unit, a negative pulse output control unit, a negative pulse transmission unit and a negative pulse output electrode wire which are electrically connected in sequence; the positive pulse transmission unit at least comprises a forward multiplication transmission unit which is used for performing forward voltage multiplication or forward current multiplication on the forward output pulse signal; the negative pulse transmission unit at least comprises a negative multiplication transmission unit which is used for carrying out negative voltage multiplication or negative current multiplication on the negative output pulse signal. The bipolar nanosecond pulse synchronous output circuit provided by the utility model can improve instant pulse energy of nanosecond pulse tumor ablation equipment.

The application relates to the field of laser technology, in particular to a device and a method for generating wide-tuning narrow-line-width mid-infrared laser, wherein the pump light emitted by a nanosecond pulse OPO base frequency pump source is reflected to a beam splitter by a full reflection mirror after passing through a first adjuster; the pump light emitted by a continuous wave OPO base frequency pump source is irradiated to the beam splitter after passing through a second adjuster; the two beams of pump light are combined after passing through the beam splitter, are focused after passing through a plano-convex lens, are irradiated to a first plano-concave full reflection mirror, and then are transmitted to a nonlinear crystal to generate signal light and idler mid-infrared laser through nonlinear frequency conversion; the idler mid-infrared laser and the residual pump light are transmitted to a doublet mirror and are separated by the doublet mirror; the signal light is reflected to the nonlinear crystal in sequence through a second plano-concave full reflection mirror, a first plane full reflection mirror, a second plane full reflection mirror and the first plano-concave full reflection mirror, and an oscillation closed loop is formed. The application realizes that the pulse OPO outputs a pulse with a line width less than 90 MHz in the tuning range, and the extraction efficiency of the idler light is as high as 9.3%.

This invention discloses a two-dimensional infrared spectroscopy system and its detection method that combines acid-base step and pulsed heating. The system includes a femtosecond laser, an optical parametric amplifier and difference frequency generator, a frequency divider, an electronic time delay generator, a nanosecond laser, a detachable optical parametric oscillator providing 355nm light pulses, an optical parametric oscillator providing 2020nm light pulses, a monochromator and a mercury cadmium telluride array detector, an integrator and data acquisition card, a computer, a chopper, a time-resolved pulse generation chamber, and a sample chamber. This invention retains the original pulsed heating trigger mode by using a nanosecond light source with a detachable optical parametric oscillator providing 355nm light pulses. It achieves convenient switching between the acid-base step and pulsed heating modes through a dichroic mirror and a reversible reflector. Before and after switching, the propagation direction of the nanosecond pulses is completely consistent, and the relative time delay is corrected by the electronic time delay device.

The invention provides a method for preparing a gradient microstructure on the surface of a current collector, and belongs to the field of laser application. The invention provides a method for preparing a gradient microstructure on the surface of a current collector. The method comprises the following steps: scanning the surface of the current collector by using combined laser; the combined laser comprises nanosecond pulse laser and femtosecond pulse laser; the output power of the nanosecond pulse laser is 50-100 W, and the output power of the femtosecond pulse laser is 15-30 W; the pulse width of the nanosecond pulse laser is 50 to 500 ns, and the repetition frequency of the nanosecond pulse laser is 10 to 50 kHz; the pulse width of the femtosecond pulse laser is 50-500 fs, and the repetition frequency of the femtosecond pulse laser is 10-50 kHz; and the speed of the combined laser during scanning is 1500-3000mm / s. The gradient microstructure meeting the service performance requirement of the current collector is prepared by regulating and controlling the output power, the pulse width, the repetition frequency and the scanning speed of the nanosecond pulse laser and the femtosecond pulse laser.

Diamond through hole forming method and device based on laser coupling high pressure water jet, including the following steps: the diamond to be processed is fixed on a three-dimensional moving processing table, high energy density of an ultrashort pulse laser is used to realize non-thermal melting processing of the diamond, and an initial blind hole with a graphite residual layer is quickly formed on the diamond; a high pressure water jet mixed with a first oxidizing corrosion component is used to act on the initial blind hole, the graphite residual layer on the initial blind hole is removed, and the blind hole is reamed; a high pressure water jet containing a second oxidizing corrosion component is sprayed, and a nanosecond pulse laser is coupled to act on the reamed blind hole, a processing mode similar to water guide laser is formed, and a set through hole structure is obtained. The three-step method of laser direct drilling pretreatment, high pressure chemical water jet reaming processing and chemical assisted laser reaming polishing is adopted, rapid and high precision processing of the diamond through hole is realized, the processing efficiency, precision and quality are greatly improved, the cost can be reduced, and the method is environmentally friendly and efficient.

The invention belongs to the technical field of laser surface modification processing, and particularly relates to a femtosecond-nanosecond double-beam laser cooperative shock peening method, which comprises the following steps of: taking a nanosecond laser and a femtosecond laser as shock peening light sources at the same time, and combining the two beams of laser through a beam combiner, focusing on the surface of the workpiece through a focusing optical system for impact strengthening; when the workpiece is subjected to shock peening, the time delay between the femtosecond pulse and the nanosecond pulse is controlled through the time delay device, so that the femtosecond laser reaches the surface of the workpiece before the nanosecond laser; the femtosecond laser firstly ionizes a material on the surface of a workpiece to form plasma, and realizes strong absorption of subsequent nanosecond laser, so that the depth of an influence layer of nanosecond impact strengthening can be achieved without an absorption layer and a water restraint layer. The method has the advantages of femtosecond laser shock peening, that is, a restraint layer and an absorption layer are not needed, and the method has the advantage of nanosecond shock peening, so that the depth of a deep influence layer can be realized.

This invention provides a full-link detection device and method for laser interferometric velocimetry systems, relating to the field of transient photoelectric testing technology. The detection device includes a pulse injection module, a signal transmission and conversion module, and a signal acquisition and analysis module. The pulse injection module includes a nanosecond pulse laser and a coupler. The coupler is connected in series between the output end of the fiber laser and the first port of the circulator. The nanosecond pulse laser, after being coupled by the coupler, is transmitted along the entire system link and converted into an electrical signal by a photodetector. The data acquisition unit acquires the signal, and the analysis unit analyzes the characteristics of the electrical signal to achieve full-link status detection. This invention can identify and locate fiber optic path breaks, determine the working status of the fiber optic probe, and predict the intensity of the interference signal in the formal experiment. Even after the system is fully solidified before the experiment, it can still monitor the entire link status in real time, effectively improving the operational reliability and efficiency of the laser interferometric velocimetry system.

The invention discloses a laser drilling device for transparent materials, which comprises a first pulse laser, a second pulse laser, a first converter, a second converter, a first collimating mirror, a second collimating mirror, a beam combiner and a focusing objective lens, the first pulse laser is used for emitting first pulse laser, the first pulse laser is microsecond pulse laser or millisecond pulse laser or nanosecond pulse laser, the second pulse laser is used for emitting second pulse laser, and the second pulse laser is picosecond pulse laser or femtosecond pulse laser; the first converter is used for converting incident first pulse laser into a first Bessel pulse light beam; the second converter is used for converting the incident second pulse laser into a second Bessel pulse light beam; the emission time point of the first pulse laser is first preset time earlier than the emission time point of the second pulse laser. Hole making can be completed through laser one-time machining, an etching procedure is not needed, and the hole making efficiency can be greatly improved.

A laser-plasma synergistic surface treatment method for CFRP / titanium alloy heterojunctions belongs to the field of heteromaterial bonding technology. First, nanosecond pulsed lasers are used to etch the surfaces of CFRP and titanium alloy to be bonded, constructing a micro-nano composite structure. Then, atmospheric pressure cold plasma is used to activate the etched surfaces, grafting polar functional groups. Finally, the two are bonded and cured using an adhesive. This invention achieves a dual enhancement effect of "mechanical interlocking" and "chemical bonding" by organically combining "laser etching to construct micro-nano physical structures" and "plasma activation to introduce chemical functional groups," significantly improving the interfacial bonding strength of CFRP / titanium alloy heterojunctions. Compared with single treatment methods, this invention can increase the joint shear strength by more than 38%, and the failure mode changes from interfacial failure to cohesive failure. It has advantages such as environmentally friendly process, good controllability, and significant effects, and has broad application prospects in aerospace, high-end equipment manufacturing, and other fields.

The invention discloses a curved surface topology microstructure surface micro-channel heat exchanger and a laser processing method thereof, and relates to the field of laser processing, and the method comprises the following steps: providing a bottom plate and a cover plate; designing a micro-channel laser processing path, a curved surface topology microstructure laser processing path and laser processing parameters; carrying out laser etching on the bottom plate by utilizing a nanosecond pulse laser according to the micro-channel laser processing path and the laser processing parameters, and etching a plurality of micro-grooves which are uniformly distributed in the length direction of the bottom plate on the surface of the bottom plate; a curved surface topology microstructure is machined on the bottom wall of each microgroove in sequence through an optical fiber laser according to the curved surface topology microstructure laser machining path and the laser machining parameters; and the bottom plate and the cover plate are fixed in a covering mode, and the curved surface topology micro-structure surface micro-channel heat exchanger is obtained. The curved surface topological microstructure surface micro-channel heat exchanger machined through the method has the good heat exchange effect and low flow resistance, and the comprehensive heat exchange performance is high.

The invention discloses a repetition frequency nanosecond pulse power source of a Marx generator based on impedance matching. The repetition frequency nanosecond pulse power source comprises a pulse forming unit, an impedance matching network and a trigger control unit which are integrated in a closed box body, the impedance matching network comprises a conical cylindrical inner conductor and multiple stages of cylindrical outer conductors which are sequentially and coaxially arranged from top to bottom, the bottom ends of the outer conductors are connected with the last-stage outer conductor, the top ends of the outer conductors are connected with an external load, and the multiple stages of outer conductors and the inner conductor form a central coaxial transmission line; the pulse forming unit comprises a plurality of stages of discharge loops which are stacked in series, and each stage of discharge loop corresponds to one stage of outer conductor; each stage of discharge loop comprises a plurality of discharge modules which are annularly arranged at equal intervals around the corresponding outer conductor; and the trigger control unit is used for generating nanosecond leading edge trigger pulses to drive the high-voltage switches of the discharge loops at all levels to be switched on. According to the invention, the cost and the size of the power source can be reduced, the energy transmission efficiency is improved, the synchronous triggering precision is improved, and the repeated-frequency nanosecond pulse output capability is stable.

The utility model provides a nanosecond pulse fiber laser. The nanosecond pulse fiber laser comprises a seed source module, a first-stage amplification module, a second-stage amplification module and a third-stage amplification module. The seed source module is used for outputting seed light, the input end of the first-stage amplification module is connected with the seed source module, the input end of the second-stage amplification module is connected with the output end of the first-stage amplification module, and the input end of the third-stage amplification module is connected with the output end of the second-stage amplification module. The seed source module comprises a directly modulated semiconductor laser diode and a first online isolator, the output end of the semiconductor laser diode is connected with the input end of the first online isolator, the input end of the primary amplification module is connected with the output end of the first online isolator, and the output end of the first online isolator is used for outputting seed light. The nanosecond pulse fiber laser provided by the utility model can solve the technical problem that the tuning frequency range is limited in the prior art.

The invention discloses a low-voltage nanosecond pulse platform waveform fitting method, and belongs to the technical field of high-frequency pulse control, and the method comprises the steps: obtaining a set voltage value, calculating the optimal pulse width corresponding to a target cell through a transmembrane voltage formula according to the set voltage value, and calculating the optimal pulse width according to a dose and transmembrane potential accumulation model. Calculating the number of equivalent nanosecond pulse sub-pulses capable of replacing the optimal pulse width, calculating the number of pulse strings according to the total dose set by the optimal pulse width and the number of the equivalent nanosecond pulse sub-pulses, fitting nanosecond pulses, and replacing the optimal pulse width, the calculated nanosecond fitting value, the calculated pulse string number and preset parameters are stored in a storage chip of the pulse platform, the pulse platform calls the storage parameters for energy emission, the low-voltage nanosecond platform can be used for achieving the combined effect of a microsecond platform and a high-voltage nanosecond platform, released bubbles are smaller than those of the microsecond platform, the occurrence rate of embolism is reduced, and the service life of the microsecond platform is prolonged. The released voltage is lower than that of traditional nanoseconds, and the problems of blood fusion and smooth muscle and nerve damage are reduced.

This invention discloses a high-amplitude, high-repetition-rate sub-nanosecond pulse source based on a parallel incremental structure of avalanche transistors, comprising: sequentially connecting a first microstrip line T1, a charging capacitor C1, a second microstrip line T2, and an avalanche transistor Q1; connecting the avalanche transistor Q1 to a third microstrip line T3; sequentially connecting the third microstrip line T3, a charging capacitor C2, a fourth microstrip line T4, and the avalanche transistor Q2; and connecting the charging capacitors C2 and C1 to a power supply E. c Connection. This invention, through the use of a parallel incremental structure of avalanche diodes, effectively increases the current-carrying capacity of a high-amplitude pulse source while minimizing the adverse effects of increased microstrip line width on the output pulse waveform. Furthermore, the parallel incremental structure of avalanche diodes reduces the number of avalanche diodes required, saving costs.

The application discloses a curved surface topological microstructure surface micro-channel heat exchanger and a laser processing method thereof, and relates to the field of laser processing.The application provides a bottom plate and a cover plate;designs a micro-channel laser processing path, a curved surface topological microstructure laser processing path and laser processing parameters;utilizes a nanosecond pulse laser to perform laser etching on the bottom plate according to the micro-channel laser processing path and the laser processing parameters, and etches a plurality of microgrooves which are uniformly arranged along the length direction of the bottom plate on the surface of the bottom plate;utilizes a fiber laser to process curved surface topological microstructures on the bottom wall of each microgroove according to the curved surface topological microstructure laser processing path and the laser processing parameters;and the bottom plate and the cover plate are fixed to obtain the curved surface topological microstructure surface micro-channel heat exchanger.The curved surface topological microstructure surface micro-channel heat exchanger processed by the application has good heat exchange effect and low flow resistance, and has high comprehensive heat exchange performance.

The invention discloses a nanosecond laser precision machining method for a SiCf / SiC composite material, and belongs to the field of laser machining and advanced composite material manufacturing. The method comprises the following steps: carrying out linear ablation or surface ablation on a pretreated SiCf / SiC composite material by adopting nanosecond pulse laser with the wavelength of 355 nm; the laser energy density, the scanning speed, the scanning times, the line overlapping ratio and the scanning path are optimized through the system, and high-precision and low-damage machining is achieved. The core optimization parameters are as follows: the laser energy density is 5.33 J / cm < 2 >, the scanning speed is 200mm / s, the line overlapping rate is 66.58%, and a one-way scanning mode is adopted. Through the combination of experiments and simulation, the mechanism (melting, evaporation, decomposition, and material removal by liquid drop splashing and gas volatilization) of nanosecond laser ablation of SiCf / SiC is disclosed, the heat affected zone, the oxidation phenomenon and the recondensate defect are effectively controlled, the quality and the contour precision of the machined surface are remarkably improved, and the machining precision is improved. The method is suitable for micromachining of key components such as aerospace engine hot end components and medical high-end equipment.

An electrocardiographic waveform-based adaptive pulse ablatograph includes at least two electrodes configured to transmit an ablation pulse to a tissue during use; a pulse waveform generator coupled to the electrodes and configured to transmit a nanosecond pulse having a voltage of 15 kv-35 kv to the electrodes; an electrocardiographic detection device configured to collect an electrocardiographic waveform signal; and a control device in signal connection to the electrocardiographic detection device and in control connection to the pulse waveform generator. By controlling duration of pulse release and the magnitude of pulse energy of the pulse waveform generator and the electrodes in the effective refractory period, the control device makes dynamic adjustment quickly according to a real-time heartbeat of a patient, thus increasing the proportion of the pulse release duration in the effective refractory period and improving the safety.