106 results about "Picosecond" patented technology

The invention discloses an OEO amplifier with a high-speed hard switching function and an optical transmission system, and relates to the technical field of optical amplifiers, the OEO amplifier comprises three magneto-optical switches, an optical splitter group, a photoelectric detector group, a real-time comparison circuit, a logic gate control circuit and a driving circuit; the photoelectric detector group collects optical signal power to generate an electric signal; the real-time comparison circuit performs voltage threshold judgment on the electric signal; the logic gate control circuit is connected with the output end of the real-time comparison circuit so as to synchronously control the switching states of the three magneto-optical switches according to a voltage threshold judgment result; the driving circuit is used for driving the magneto-optical switch to synchronously execute a switching action; when the OEO amplifier detects that optical signals in any direction are interrupted, all the magneto-optical switches finish synchronous switching within 100 microseconds, and the end-to-end optical signal switching time difference is smaller than 2 picoseconds. The method is suitable for a single-fiber bidirectional optical communication environment requiring high frequency, high precision and high stability.

The invention provides a covalent organic framework material as well as a preparation method and application thereof, 1, 3, 6, 8-tetra (4-aminophenyl) pyrene is selected as a central construction unit, and a trap state is realized in a covalent organic framework (COFs) by regulating and controlling the symmetry of active sites (benzothiadiazole, BT). Compared with a centrosymmetric counterpart in the COFs, by breaking the symmetry of the center BT core, the trap state density in the COFs can be remarkably reduced, and the service life of the shallow trap state can be prolonged to 1160.02 picoseconds. Therefore, more photo-induced electrons can participate in the photocatalytic reaction, and the remarkable performance (greater than 99%) of photocatalytic reduction of uranium (VI) is finally realized. According to the invention, the key effect of symmetric breaking in inhibition of excited state decay of COFs is clarified for the first time, and a profound solution is provided for understanding how to improve the photocatalytic performance of COFs in environmental restoration.

The invention discloses a photoconductive switch, a manufacturing method and a high-voltage-resistant picosecond electric pulse device, relates to the technical field of semiconductor devices and can also be applied to the field of microelectronics, and the photoconductive switch comprises a substrate layer, and a low-temperature gallium arsenide layer, a top insulating layer and a top electrode layer which are sequentially stacked on the substrate layer, wherein the top electrode layer comprises a first pin and a second pin, and the first pin and the second pin are embedded into the low-temperature gallium arsenide layer through the top insulating layer. According to the technical scheme, the electrode with a certain depth is embedded into the gallium arsenide growing at low temperature, so that the current density can be reduced, and the heat dissipation performance and the voltage resistance of the photoconductive switch are enhanced.

The present invention discloses a system and method for continuous observation of multiple time scales during femtosecond laser processing. The system comprises a femtosecond laser light source, a laser processing system, a pulse shaping system, and a multi-time scale continuous observation system. The multi-time scale continuous observation system comprises a femtosecond ultrafast continuous imaging system, a picosecond-nanosecond ultrafast pump-probe system, a nanosecond-millisecond ICCD continuous imaging system, and a microsecond-second high-speed camera system. Compared to other ultrafast imaging systems, the present invention enables ultrafast continuous observation of femtosecond laser processing across multiple time scales. Its observation time range extends over 13 orders of magnitude, from hundreds of femtoseconds to seconds, encompassing the entire physical and chemical reaction process. This system plays a crucial role in providing a deeper understanding and understanding of a range of nonequilibrium and nonlinear ultrafast phenomena in femtosecond laser processing.

The present disclosure provides a time compensation method and system for interference test equipment. The method includes: obtaining a first delay time and a second delay time; decomposing the first delay time and the second delay time to obtain a nanosecond scale delay time corresponding to the first delay time and a picosecond scale delay time corresponding to the second delay time; performing lead compensation for the nanosecond scale delay time by a configurable lead compensation and output module to obtain a nanosecond scale lead compensation time; performing lag compensation for the picosecond scale delay time by a delay compensation module to obtain a picosecond scale delay compensation time, and calculating a sum of the nanosecond scale lead compensation time and the picosecond scale delay compensation time to obtain a picosecond scale lead compensation time; and applying an interference signal on a controller area network, CAN, bus based on the picosecond scale lead compensation time. Therefore, by using a plurality of timing controllers connected in cascade in the delay compensation module, the picosecond scale delay compensation time is realized.

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 invention discloses a broadband FP (Fabry-Perot) cavity transmission spectral line calibration method and a calibration spectral line generation device, and belongs to the field of astronomical spectrum calibration. According to the invention, the laser frequency comb is utilized to carry out precise calibration on the FP cavity, the precision is an Hz magnitude, and the calibration precision of the radial velocity of the FP cavity can reach m / s; by tuning laser frequency comb parameters, all transmission peaks are supplemented, and broadband coverage is achieved; the high precision requirement for FP cavity coating is avoided, the accuracy of transmission spectral lines is ensured, frequent calibration is performed on the FP cavity, and the problem that the FP cavity cannot provide long-term stability of frequency is solved; a low-repetition-frequency picosecond white light source is used, the spectrum is wide and flat, the spectrum is not sensitive to the position of a transmission peak of an FP cavity, and the light enters a calibrated FP cavity array to generate a calibration spectral line with a high signal-to-noise ratio and multiple frequency intervals, so that the calibration precision of the astronomical spectrometer reaches the cm / s-level radial velocity calibration precision. The method is applied to the calibration of the astronomical spectrometer for extrasolar planet search.

The invention relates to a radio frequency millimeter wave ultra-low noise single-stage sampling phase-locked loop comprising a sampling phase discriminator used for carrying out instantaneous sampling on a reference signal according to a picosecond-level narrow pulse signal and outputting a sampling voltage, the reference signal and the picosecond-level narrow pulse signal having the same frequency; the series resonance voltage-controlled oscillator based on the transformer is connected with the sampling phase discriminator and used for adjusting the oscillation frequency of the series resonance voltage-controlled oscillator according to the sampling voltage and outputting a high-frequency signal; the frequency divider is connected with the voltage-controlled oscillator and is used for carrying out frequency division on the high-frequency signal and outputting a clock control signal; and the clock generation module is connected with the frequency divider and the sampling phase discriminator and is used for generating a picosecond-level narrow pulse signal according to the clock control signal. The sampling phase-locked loop provided by the invention realizes effective suppression of noise, and has the advantages of low phase noise, low reference stray and small area.

The invention provides an FPGA-based programmable periodic pulse signal generation method and application thereof, and belongs to the technical field of electronic measurement. In order to solve the problems that the large dynamic range and the high resolution are difficult to consider at the same time and hardware resources are consumed synchronously by multiple channels in the prior art, according to the method, coarse delay is achieved through FPGA system clock counting, and next pulse parameters are calculated through accumulation of remaining decimal parts; picosecond-level fine delay is realized by constructing a three-level cascade architecture consisting of a lookup table, a coarse carry chain and a fine carry chain; and XOR synthesis waveforms after rising edges and falling edges are independently generated respectively. In addition, the inter-channel transmission delay difference is compensated by correcting the initial calculation parameters. According to the multi-channel pulse signal generation circuit, high-precision, low-jitter and strictly-aligned-phase multi-channel pulse signals can be generated only by utilizing pure logic resources of the FPGA.

The invention relates to the technical field of laser processing, in particular to a metal surface solder mask processing method and device. Comprising the steps that a laser emits ultraviolet laser; adjusting the position and the size of a focusing light spot of the ultraviolet laser; the position of the metal product to be machined is adjusted, so that the light spot of the ultraviolet laser is focused on the metal product to be machined; controlling the laser to emit laser according to a set frequency and a set light emitting method to process a solder mask on the surface of the to-be-processed metal product; the set light emitting method is a light emitting processing method in which the light emitting time t1 picosecond and then the non-light emitting time t2 picosecond are taken as a light emitting period and n light emitting periods are taken as a processing cycle. According to the metal surface solder mask layer machining method, submicron-level accurate energy deposition is achieved, the non-equilibrium phase change process is triggered, the metal surface is promoted to generate a highly-ordered microcrystalline structure, and the uniformity and consistency of the solder mask layer are improved.

Disclosed is a process for cutting a metallic-glass strip, comprising applying to the strip a pulsed laser beam of wavelength shorter than or equal to 555 nanometers, the pulsed laser beam being formed of a succession of pulses each having a duration shorter than 10 picoseconds, and advantageously shorter than 1 picosecond, the crystallization temperature of the metallic glass being below 500° C., and the light energy of the laser beam incident on the strip being comprised between 1 and 10 microjoules per pulse.

This invention provides a covalent organic framework material, its preparation method, and its applications. The invention selects 1,3,6,8-tetra(4-aminophenyl)pyrene as the central building block and achieves trapped states within covalent organic frameworks (COFs) by controlling the symmetry of the active site (benzothiadiazole, BT). Compared to its centrosymmetric counterpart, by breaking the symmetry of the central BT core, the density of trapped states in COFs can be significantly reduced, and the lifetime of shallow trapped states can be extended to 1160.02 picoseconds. This allows more photogenerated electrons to participate in the photocatalytic reaction, ultimately achieving significant photocatalytic reduction of uranium (VI) (>99%). This invention elucidates for the first time the crucial role of symmetry breaking in suppressing excited-state decay in COFs, providing profound insights into how to improve the photocatalytic performance of COFs in environmental remediation.

The present invention provides an ultrafast time-compressed image acquisition method based on on-chip storage, which is used to address the technical problem that the ultrafast compression imaging technology of a streak camera for a target scene is limited by the working principle of the streak tube, resulting in a time resolution of the order of picoseconds to sub-nanoseconds and a low spatial resolution. The method of the present invention comprises: selecting pixel areas with pixel resolutions of M×N and M×L as imaging photosensitive areas and imaging storage areas, respectively; making a pseudo-random mask plate to cover the imaging photosensitive area, and covering the imaging storage area with an opaque mask plate; imaging the target scene on the imaging surface of the imaging photosensitive area; exposing the target scene and performing an initial image, and transferring the image of the imaging photosensitive area as a whole by one row along the charge storage transfer direction; after the transfer is completed, exposing the imaging photosensitive area and continuing to acquire the image, and executing i=i+1 after the exposure is completed; if i≤L, outputting the next row of images, and so on until i>L, thereby obtaining a time-compressed image of the target scene.

The invention discloses a carving machining method and system based on vector pulse laser, and belongs to the technical field of laser carving, the carving machining method based on the vector pulse laser comprises the steps that linear polarization femtosecond pulse laser is split into femtosecond pre-pulse laser and picosecond main pulse laser; adjusting the pulse time delay between the femtosecond pre-pulse laser and the picosecond main pulse laser; combining the femtosecond pre-pulse laser and the picosecond main pulse laser after delay regulation and control; the femtosecond pre-pulse laser is converted into an angularly polarized femtosecond pre-pulse light beam, the picosecond main pulse laser is converted into a radially polarized picosecond main pulse light beam, and a double-pulse light beam combination of the angularly polarized femtosecond pre-pulse light beam and the radially polarized picosecond main pulse light beam is formed; and the to-be-machined workpiece is ablated and engraved through the double-pulse light beam combination. And by means of the synergistic effect of double pulses and precise time delay, the width and fusion damage of a heat affected zone are remarkably reduced, and high-precision and low-damage carving machining is achieved.

The present invention provides a high-repetition-rate extreme ultraviolet radiation light source and an EUV lithography machine light source, wherein a portion of the target laser pulses is incident on a megawatt-class optical gain cavity to generate a second infrared laser pulse with a megawatt average power; another portion of the target laser pulses is incident on a room-temperature very high frequency photocathode microwave electron gun after frequency doubling and shaping, driving the room-temperature very high frequency photocathode microwave electron gun to generate a continuous picosecond electron beam with a repetition rate of hundreds of megahertz; the continuous picosecond electron beam is incident on the megawatt-class optical gain cavity and undergoes inverse Compton scattering with the second infrared laser pulse to generate radiation in the extreme ultraviolet band; further, by adjusting the energy of the continuous picosecond electron beam and the laser incident angle, the wavelength of the scattered light can be adjusted within a certain range, thereby realizing a high-repetition-rate extreme ultraviolet radiation light source.

The application discloses a kind of ultrafast pulse laser autocorrelation measurement system and method, comprising: beam splitting unit;Reference light path;Delay light path;Adjustable delay unit;Delay light mirror group;Reference light mirror group;Combining unit;Focusing unit;Asymmetric air nanoslit photodetector, for receiving the light beam output by combining unit and focusing unit, and output corresponding photocurrent signal;Signal acquisition and processing unit, for acquiring photocurrent signal, and obtaining the intensity autocorrelation curve of ultrafast pulse laser according to the time delay change relationship of photocurrent signal, and inversion obtains the pulse width information of ultrafast pulse laser.The application utilizes asymmetric air nanoslit photodetector to directly output photocurrent signal, realizes the autocorrelation measurement of ultrafast pulse laser, without nonlinear crystal, compact structure, easy to integrate, suitable for measuring femtosecond or picosecond ultrafast pulse laser.

The full-automatic cutting disc production equipment comprises a machine frame, one side in the machine frame is connected with a moving platform which is of a step mechanism, the moving platform is connected with a first jacking and transplanting mechanism and a second jacking and transplanting mechanism which are the same in mechanism, and the lower step of the moving platform of the step mechanism is connected with an X-axis sliding platform; the X-axis sliding platform is connected with a Y-axis sliding platform, the Y-axis sliding platform is connected with a Z-axis lifting platform, the Z-axis lifting platform is connected with a cutting head, the cutting head and a picosecond cutting light path device installed in the rack form a cutting light path, and an upper step of the moving platform is connected with a galvanometer splitting gantry. A galvanometer splitting machining head is connected to the galvanometer splitting gantry, the galvanometer splitting gantry and a CO2 light path device installed in the rack form a CO2 light path, and the galvanometer splitting machining head and the cutting head both move in the first jacking and transplanting mechanism and the second jacking and transplanting mechanism. The working efficiency can be improved.

1. Name of the product in this design: Infrared Picosecond Cutting Machine. 2. Application of this design: for cutting glass, ceramics, monocrystalline silicon, etc. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: a 3D model.

A device for the generation of ultrashort pulses, wherein an oscillator is formed by: a first and a second non-overlapping transmission band-pass filter, which can serve as reflecting end element of the oscillator; optically transparent means with non-linear Kerr coefficient χ(3) different from zero configured to achieve a spectral broadening by self-phase modulation of the signal transiting through these means; an optical waveguide that produces a positive gain; a node configured to receive a trigger signal designed to activate the operation of the oscillator; a trigger signal generating device comprising: a laser source, for example a microchip, configured to generate a laser pulse, preferably with a minimum bandwidth, having a duration of hundreds of ps, up to the ns; a coupling system designed to introduce the pulse of the trigger laser into a waveguide made of an optically transparent material characterised by a non-linear Kerr coefficient χ(3) different from zero, which is configured to produce two distinct effects in order to spectrally broaden the pulse of the trigger laser, and precisely: a) self-phase modulation four-wave mixing; the output of the waveguide supplies the trigger signal to the node. The pulses produced by the oscillator typically have a duration of the order of the picosecond and are easily reduced to the Fourier limit of circa 100 femtoseconds by means of a dispersive device.

An image acquisition method comprising: a step of generating an optical excitation pulse group comprising a plurality of repeated optical excitation pulses; a step of emitting the optical excitation pulse group toward an object containing a fluorescent dye; a step of detecting fluorescence intensities generated at a plurality of locations on the object due to the emission of the optical excitation pulse group; and a step of generating a fluorescent image based on the fluorescence intensities at the plurality of locations on the object. In the step of generating the optical excitation pulse group, a time interval between the plurality of optical excitation pulses is set to be equal to or shorter than a relaxation time between excited triplet states of the fluorescent dye or shorter than 10 picoseconds.

This invention discloses a sub-picosecond ultrafast scintillator, its preparation method, and its applications. The invention employs ligand-assisted deposition and high-temperature thermal injection to prepare all-inorganic metal halide perovskite CsPbCl3 nanocrystals. Through size optimization and ligand engineering, a strategy is proposed to passivate shallow defect levels, reducing the carrier residence time in shallow defect states while appropriately retaining deep defect levels. This achieves exciton recombination path renormalization in the nanocrystals, ultimately realizing ultrafast scintillation of <100 ps at room temperature.

The invention discloses a time spectrometer system and method based on a microchannel plate photomultiplier (MCP-PMT). The constant proportion discriminator is triggered by adopting an attenuation branch / delay branch differential zero crossing point, and performs latch width limiting and level conversion on a trigger pulse; fPGA-based multi-level carry chain time TDC is adopted, and parallel tap sampling, bubble suppression and code density calibration table look-up correction are carried out; a processing flow of time window histogram accumulation, a first effective hit strategy, a background adaptive threshold and multi-peak positioning and fitting is adopted. According to the invention, the picosecond-level timing precision is obtained at a low clock rate, the sensitivity and precision of weak light signal flight time distance measurement are significantly improved, and the method is suitable for laser radar imaging and high time sequence of time correlation single photon counting, can realize sub-hundred picosecond-level time resolution, and is suitable for flight time distance measurement under a weak light condition.

The invention discloses a multi-principal-element alloy irradiation defect evolution method, which relates to the technical field of material irradiation effect simulation and prediction, and comprises the following steps: performing statistical fitting on formation energy and migration energy obtained by processing a plurality of set super-cell models with different element concentrations, and extracting half-peak width and distribution overlap ratio indexes; initializing a molecular dynamics cascade collision simulation condition, and counting the concentration of the generated initial defect cluster; generating diffusion coefficients, absorption coefficients, dissociation rates and annihilation rates of the clusters with various sizes by means of a random sampling method, and eliminating transitions exceeding an energy threshold value; substituting the rate list and the initial concentration into an energy-resolved cluster dynamics main equation, performing integration, and outputting a result; the method provided by the invention can accurately capture the local chemical non-uniformity in the multi-principal element alloy to dynamically regulate and control the defect cluster dynamics, not only covers the full time scale from the picosecond level to the second level, but also greatly improves the simulation precision and the prediction reliability through the statistical distribution model and dynamic parameter updating.

1. The name of the product under this design: Beauty instrument (picosecond). 2. Purpose of this design product: for beauty and care. 3. The key point of the design of this product lies in its shape. 4. The picture or photo that best illustrates the design points: three-dimensional picture.

The application discloses a multi-output low-frequency picosecond mode-locked fiber laser based on a cascade contrast differential beam splitter, which comprises a fiber grating, a gain fiber, a cascade light splitting network, a saturable absorber and a pump coupler for injecting pump light into the gain fiber; the fiber grating, the gain fiber, the cascade light splitting network and the saturable absorber are sequentially connected and constitute a linear resonant cavity with a target set length, and the fiber grating in the linear resonant cavity is connected with the pump coupler to build a linear cavity fiber laser; the length of the entire linear cavity fiber laser can be controlled by controlling the target set length of the linear resonant cavity composed of the fiber grating, the gain fiber, the cascade light splitting network and the saturable absorber, so that the volume of the linear cavity fiber laser is smaller, and meanwhile, after the target set length of the linear resonant cavity is controlled, low repetition frequency can be realized directly in a fundamental mode without complex harmonic mode-locking control.

The invention discloses a SiC crystal ingot laser stripping device in the technical field of semiconductor material laser processing, and the SiC crystal ingot laser stripping device comprises a sealing cover and a stripping sheet, the upper end of the sealing cover is fixedly provided with a sealing cover, the sealing cover and the sealing cover form a closed space, the closed space is internally provided with a stripping assembly, and the stripping assembly comprises a stripping frame, a laser output mechanism is arranged at the upper end of the stripping frame, the laser output mechanism comprises a multi-pulse dynamic switching system, femtosecond, picosecond and nanosecond pulse widths can be dynamically switched, and stress distribution and crack propagation characteristics of non-uniform areas such as a defect area and a doping layer in the crystal can be flexibly adapted; according to the invention, through femtosecond / picosecond / nanosecond pulse width dynamic switching and adaptation to the conductivity and thermal diffusion characteristics of a non-uniform region, accurate control of cracks / stress of a defect region and a conductive transition region is realized, high wafer yield and low loss are ensured, and the device is suitable for production of large-size high-quality SiC wafers.

The invention discloses a laser repairing method for a thermosetting carbon fiber reinforced resin-based composite material, relates to the technical field of carbon fiber composite material repairing, and is suitable for in-situ efficient repairing of military and civilian components in the aviation field. Aiming at the problems of secondary damage, low efficiency and poor interface bonding in the prior art, the method comprises the following steps: 1) removing a damaged area by picosecond or femtosecond laser, and processing a step structure of a repair area; 2) etching a microgroove which is consistent with the surface carbon fiber in direction, the depth D of the microgroove meets the condition that D is equal to 5 + 0.656 * [(TlaserTmelt) * MFR] 0.4, and the width W of the microgroove meets the condition that W / D is larger than or equal to 0.5 and smaller than or equal to 5; (3) a thermoplastic film is laid in the repairing area, and fusion anchoring is achieved through laser irradiation in combination with rolling or fixed compaction; 4, the thermoplastic prepreg tape is laid through large-spot laser, filling is completed in a multi-layer and multi-channel mode, according to another preferred embodiment, the thermoplastic film is pre-compounded on the surface of the prepreg tape, and the independent film laying step is omitted. According to the method, the repairing period of the carbon fiber composite material can be greatly shortened, the method is suitable for various damage types, and efficient and high-quality in-situ repairing is achieved.

The application discloses an ultrafast imaging device and method, which comprises, along an optical path, an ultra-short pulse laser, a time-domain shaping mechanism for separating the ultra-short laser pulse into light of different wavelengths and separating the light of different wavelengths in time, a space-domain shaping mechanism for separating the light of different wavelengths after time separation into multiple regions and converting the light into multiple parallel light beams to irradiate the sample at different incident angles, an objective lens for multiple frame imaging of the sample after irradiating the sample, a second convex lens array for mapping each frame of image to different positions of a high-speed camera, and a high-speed camera for simultaneously capturing multiple frames of images of the ultrafast phenomenon. The application has the advantages of simple structure, high stability, convenient operation, conventional elements, low cost for capturing the ultrafast phenomenon, flexible setting of the imaging time scale in the range of femtosecond or picosecond, and integration of multiple super-resolution and high-field methods.

The invention discloses a refraction type pulse radiation detector based on multi-wavelength compensation and a dynamic range expansion method thereof, and solves the problems that when ray pulse intensity input by an existing refraction type pulse radiation detector is high, a large phase difference is generated between signal light and reference light, an output signal of an interferometer is reduced when reaching a certain value, and the dynamic range of the refraction type pulse radiation detector is influenced. The problem that the measurement dynamic range of the refraction type pulse radiation detector is limited due to the fact that the external output is not increased continuously is solved. The number of paths of probe light is reasonably designed, a plurality of interferometers with complementary linear intervals can be obtained, the dynamic range limitation of a single-path interferometer is broken through, the dynamic range of the refraction type pulse radiation detector is effectively expanded, meanwhile, the advantages of the single-path refraction interferometer are reserved, namely, the picosecond-order intrinsic time resolution is achieved, and the detection precision is improved. Meanwhile, pulse signals can be transmitted remotely, the front end is full-optical, and the anti-electromagnetic interference capability is high.

A method for manufacturing a stone for a timepiece from a mineral body of a monocrystalline type, the stone including a hole, includes ablating the body by scanning at least one face of the body with ultra-short pulse laser radiation from a laser for a duration less than one hundred picoseconds, and guiding a beam of the laser radiation using a precession system of at least three axes configured to at least partially cancel a conical focusing angle of the laser. The ablating includes digging of a cone of entrance to the hole. A mineral stone of monocrystalline type for a timepiece includes a face provided with a hole formed in a body of the stone, and a functional element at an entrance to the hole. The functional element has a shape of a cone.