242 results about "Nanosecond pulse" patented technology

The invention discloses a photoacoustic spectrum-confocal Raman spectrum multi-view-field high-dimensional imaging method and a photoacoustic spectrum-confocal Raman spectrum multi-view-field high-dimensional imaging device. Nanosecond pulse laser with adjustable wavelength is generated through a continuous spectrum nanosecond pulser and a narrow-band spectrum tuning module and cooperates with a microscopic detection module, a depth imaging module, a galvanometer system and an electric displacement table to obtain spatial three-dimensional data, a photoacoustic spectrum and a Raman spectrum under multiple view fields; shallow photoacoustic spectrum-Raman spectrum tomography and deep three-dimensional photoacoustic imaging are realized; correcting a photoacoustic spectrum quantitative error by using a spectrum decoupling algorithm, and fusing the multi-view-field data to generate multi-view-field high-dimensional photoacoustic spectrum-Raman spectrum data; high-dimensional data features are extracted based on a 3D convolution instance segmentation network, and quantitative analysis and spatial distribution visualization of blood oxygen, inflammatory factors and the like are achieved. According to the method, the limitation that substances are difficult to analyze in photoacoustic imaging is overcome, the contradiction between the imaging resolution and the penetration depth is solved, and an accurate analysis means is provided for diagnosis of diseases such as knee osteoarthritis and sepsis.

Disclosed is a detection device for laser spot welding micro-weld spot quality based on laser ultrasound, comprising: a nanosecond pulsed laser configured to emit a laser; a half-wave plate configured to generate a phase difference of the laser; a scanning galvanometer configured to focus the laser as a point source and excite an ultrasonic wave on a surface of a sample; a multi-axis displacement platform configured to place and / or move the sample; a laser Doppler vibrometer configured to emit a probe light; an image sensor configured to acquire image data of the sample in a plurality of attitudes; an optical filter configured to receive the probe light to adjust an intensity of the probe light; and a processor configured to be in communication connection with the image sensor, the optical filter, the nanosecond pulsed laser, the scanning galvanometer, the multi-axis displacement platform, and the laser Doppler vibrometer.

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.

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

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 provides a laser-induced plasma visualization experiment platform and a use method. The laser-induced plasma visualization experiment platform comprises a laser-induced breakdown module, an image acquisition module and a control module, the laser-induced breakdown module comprises a laser used for emitting pulse laser, an attenuator, a beam compressor and a beam splitter are sequentially arranged in the pulse laser propagation direction of the laser, and a reflector, an amplification objective lens and a cuvette are arranged in the propagation direction of a beam of pulse laser split by the beam splitter; the image acquisition module comprises a high-speed camera and an ICCD (Intensified Charge Coupled Device) camera, and a lens of the high-speed camera and a lens of the ICCD camera are both compared with the cuvette; the control module comprises a computer control submodule and a signal generator, the computer control submodule is in communication connection with the signal generator, the high-speed camera and the ICCD camera, and the signal generator is in communication connection with the laser, the high-speed camera and the ICCD camera. According to the platform, the whole dynamic process of induced breakdown of nanosecond pulse laser in liquid is visualized.

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 method for electrically activating oocytes based on nanosecond pulses. Single oocytes are sequentially and uniformly arranged between two parallel electrodes of an electrode dish, the electrode dish is characterized in that the distance between the electrodes is 1 mm, the electrodes are placed in a culture dish, and the two ends of the two electrodes are sealed; a culture solution is firstly put between the electrodes which are arranged in parallel, mineral oil is covered to prevent the culture solution from being evaporated, after preheating treatment, oocytes are sequentially and uniformly put between the two electrodes which are arranged in parallel one by one, and then nanosecond pulse electric activation treatment is applied. The electrodes which are arranged in parallel are adopted, the oocytes are sequentially and uniformly placed between the electrodes in a single mode, the situation that the electric pulse effect is reduced due to adhesion and stacking of all the cells is avoided, the oocytes receive uniform and equivalent electric pulse sequences, the action effect and stability of electric pulses on the cells are obviously improved, and the operation efficiency of the oocytes is improved. And the reliability and reproducibility of a test conclusion are improved.

The invention relates to a high-peak power nanosecond pulse fiber laser and a use method, and belongs to the technical field of fiber lasers. The nanosecond pulse optical fiber laser sequentially comprises a nanosecond pulse seed, a seed isolation filter arranged at the output end of the nanosecond seed, a first-stage amplification structure, a second-stage amplification structure arranged behind the first-stage amplification structure, a passive homogenization optical fiber, a third-stage amplification structure and an anti-resonance hollow-core optical fiber. And before entering the three-stage amplification, a passive homogenizing optical fiber is adopted to degrade the beam quality of the signal light, a high-order mode is further excited, energy distribution is homogenized, the highest energy density borne by the end face of the optical fiber is reduced, various nonlinear effects are further inhibited, and nanosecond pulse laser output with higher peak power is realized.

The invention relates to a nanosecond fiber laser and method for high-order chaotic pulses. A fiber ring cavity of the laser comprises a wavelength division multiplexer, an erbium-doped fiber, a first polarization controller, an analyzer, a second polarization controller, an output coupler, a dispersion control unit, a fiber isolator and a band-pass filter which are connected in sequence. The method comprises the steps that pumping continuous light is coupled into the laser through the wavelength division multiplexer; pumping continuous light is absorbed by using an erbium-doped optical fiber and is stimulated to radiate a long-wave-band gain pulse; under the combined action of the first polarization controller, the polarization analyzer and the second polarization controller, an equivalent saturable absorption effect is generated by utilizing nonlinear polarization rotation generated when gain pulses are propagated in an optical fiber, and large anomalous dispersion is introduced to realize generation of nanosecond pulses; through the band-pass filter, nanosecond pulses are allowed to be generated, and meanwhile, the nonlinear increasing speed of propagation and accumulation of the nanosecond pulses in the cavity is controlled, so that order-by-order generation of high-order chaotic pulses is realized. According to the invention, reliable output of high-order chaotic pulses can be realized.

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 mid-infrared optical parametric oscillator pumped by the dual-wavelength nanosecond pulse solid laser can simultaneously output 1.9 micron laser and 2.1 micron laser, realizes broad spectrum / multi-wavelength output of the mid-infrared optical parametric oscillator, and can ensure that mid-infrared laser has excellent beam quality and relatively high output power. The output power of the 1.9 [mu] m optical fiber laser pumping source is hectowatt magnitude, and the 1.9 [mu] m optical fiber laser pumping source serves as a pumping source of a Ho crystal in the solid laser oscillator. In a Tm solid laser oscillator and a Ho solid laser oscillator, a resonant cavity comprises two plano-concave sub-cavities, the two plano-concave sub-cavities are a Tm crystal oscillation cavity and a Ho crystal oscillation cavity respectively, the two plano-concave sub-cavities share one output mirror, the Tm crystal oscillation cavity adopts a 793 nm semiconductor laser for pumping, and the Ho crystal oscillation cavity adopts a 1.9 [mu] m optical fiber laser pumping source I for pumping; in the phosphorus-germanium-zinc optical parametric oscillator, a planar four-mirror annular cavity is used as a single-resonance optical parametric oscillation cavity.

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 invention relates to the technical field of slice lasers, in particular to a Yb-based high-power pulse slice laser with an adjustable pulse width. Comprising a pumping source, a multi-pass pumping module and a resonant cavity which are sequentially arranged along a light path, and the resonant cavity is composed of a first end mirror, a thin-sheet crystal, a thin-film polaroid, a quarter-wave plate, an electro-optical switch and a second end mirror according to the light path sequence. The slice crystal serves as a gain medium and is used for pumping pump light and generating a laser beam; the thin film polarizer highly transmits horizontal polarized light and highly reflects vertical polarized light and is used for outputting laser in the cavity, the quarter-wave plate and the electro-optical switch are used for controlling loss in the cavity so as to output nanosecond pulses, and the plane mirror is used as a resonant cavity end mirror. The pulse width output by the slice laser can be effectively regulated and controlled, the regulation range reaches ten to hundreds of nanoseconds, and the power output by the laser does not change along with the change of the pulse width.

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 invention relates to the technical field of lasers, and discloses a narrow-linewidth subnanosecond laser. The narrow-linewidth subnanosecond laser comprises a pumping source, a resonant cavity and a coupling system, the pumping source, the resonant cavity and the coupling system are arranged along the same optical axis, and the pumping source serves as gain laser. A laser crystal, a polaroid, a quarter-wave plate, an electro-optical modulator and a Bragg grating are sequentially arranged in the resonant cavity along an optical axis. The end face of the Bragg grating away from the coupling system is plated with a beam-splitting film. Laser forms oscillation in the resonant cavity, and the Bragg grating plays a role in screening longitudinal modes, so that narrow linewidth output is realized. The polaroid and the quarter-wave plate are matched to play roles of polarization analysis and light splitting. The voltage on the electro-optical modulator is periodically adjusted to periodically adjust the loss in the resonant cavity so as to output the subnanosecond pulse laser.

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%.

An expandable interbody fusion device and an associated instrument for inserting the device into an intervertebral disc space, expanding the device and for use in delivering graft material into the device once expanded in the disc space. The device is small enough to fit through Kambin's triangle yet is capable of expanding both in the vertical direction to accommodate spinal lordosis and in the lateral direction to provide sufficient structural support for opposing vertebral bodies laterally within the disc space. A process of forming textured top and bottom surfaces of the device by initially laser ablating each surface with a nano-second pulsed laser followed by laser ablating those surfaces with a femto-second pulsed laser.

Some embodiments include a nanosecond pulse generator circuit. In some embodiments, the nanosecond pulse generator circuit may include: a high-voltage power supply; a nanosecond pulse generator electrically coupled to the high-voltage power supply and switching a voltage from the high-voltage power supply at a high frequency; a transformer having a primary side and a secondary side, the nanosecond pulse generator electrically coupled to the primary side of the transformer; and an energy recovery circuit electrically coupled to the secondary side of the transformer. In some embodiments, the energy recovery circuit includes: an inductor electrically coupled to the high-voltage power supply; a crowbar diode arranged in parallel with the secondary side of the transformer; and a second diode disposed in series with the inductor and arranged to conduct current from a load to the high-voltage power supply.

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.