16 results about "Time resolved spectra" patented technology

The application discloses a pump-repump-probe time-resolved spectrum system for measuring luminescence and absorption, comprising a laser beam splitting module, a probe light path construction module, a pump light path regulation module, a repump light path adjustment module, a double-channel signal acquisition module and a light path coupling and converging module. The same femtosecond laser is used to split a light beam, two-stage light splitting is performed to obtain initial light beams of pump, repump and probe light paths, and each light path is subjected to delay adjustment, wavelength conversion, focusing and other treatments, and then is precisely coupled at the same spatial position of a sample. The double-channel signal acquisition module synchronously captures luminescence signals and probe light transmission signals of the sample, and realizes data acquisition in combination with reference light path calibration. The test method acquires multidimensional dynamic information through light path optimization, light beam coupling, signal synchronous acquisition and analysis. The system realizes synchronous detection of luminescence and absorption signals under the same excitation condition, and solves the test error and single mode limitation of the traditional independent system.

The present application relates to a time-resolved spectrum measurement method and apparatus based on a multi-event time-to-digital converter, a device, and a medium. The method comprises: a multi-event time-to-digital converter performs histogram statistics on photon signals, which are responded at different times and correspond to each column of single-photon avalanche diodes, in different laser pulse periods, so as to determine photon signal distributions of a photon signal of a specific wavelength corresponding to each column of single-photon avalanche diodes in the different laser pulse periods; and the multi-event time-to-digital converter performs delayed merging on the photon signal distributions in the different laser pulse periods to determine a photon lifetime curve corresponding to the photon signal of a specific wavelength corresponding to each column of single-photon avalanche diodes, and integrates the photon lifetime curve corresponding to the photon signal of a specific wavelength corresponding to each column of single-photon avalanche diodes to construct a time-resolved spectrum of a sample to be measured. The present application can reduce the count loss or time error caused by dead time.

The invention discloses a time-resolved metal material tensile strength detection device and method, and belongs to the technical field of metal material mechanical property detection. The method comprises the following steps: 1, configuring sample spectrum acquisition by using a time-resolved metal material tensile strength detection device; 2, respectively constructing a spectrum matrix Mn under different delay time; 3, sequentially carrying out saturation removal, abnormity removal, background removal and normalization on the spectrum matrix to form a sample initial feature vector; 4, respectively acquiring training set feature matrixes under different delay times, and forming training set feature input of the prediction model by adopting a variable screening and recombination mode; 5, performing multi-fold cross validation by using the randomly selected part of samples to adjust hyper-parameters so as to obtain a prediction model; the trained prediction model is used for metal material tensile strength detection; compared with the prior art, the technical problem of low accuracy in metal material tensile strength detection is solved by adopting the time-resolved spectrum.

The application relates to a time-resolved spectrum measurement method, device, equipment and medium based on a multi-event time-to-digital converter. The method comprises the following steps: a multi-event time-to-digital converter performs histogram statistics on different time response photon signals in each column of single-photon avalanche diodes in different laser pulse periods, so as to determine the photon signal distribution of the photon signals of a specific wavelength corresponding to each column of single-photon avalanche diodes in different laser pulse periods; the multi-event time-to-digital converter performs delay combination on the photon signal distribution in different laser pulse periods, so as to determine the photon lifetime curve corresponding to the photon signals of the specific wavelength of each column of single-photon avalanche diodes, and integrate the photon lifetime curve corresponding to the photon signals of the specific wavelength of each column of single-photon avalanche diodes to construct a time-resolved spectrum of a sample to be detected. The application can reduce the count loss or time error caused by the dead time.

The invention relates to the technical field of ultrafast optical and time-resolved spectral measurement, in particular to a pumping spectrum detection device with adjustable chirp and adjustable time delay. Comprising an ultrafast laser source, two grating dispersion units, a distance adjusting device, a laser climbing mirror, a beam splitting and energy control device, an independent delay line, a focusing lens, a light beam terminator, a sample module, a collimation attenuation module, a spectrum detection module and a synchronous control module. The method has the beneficial effects of chirp-delay decoupling, wide-range linear dispersion, stable space-time coincidence, multi-sample compatibility, automation, high signal noise, and parameter calibration and reproducibility.

This invention discloses an online defect detection method in the fabrication process of silicon carbide chips, specifically relating to the field of semiconductor defect detection technology. The method adaptively adjusts laser parameters based on the quality of real-time acquired photoluminescence signals to excite hidden defects and generate characteristic signals. Time-resolved spectral acquisition of the signals is performed, and background noise and self-absorption effects are decoupled using a nonlinear separation model to extract hidden defect features. The signal distribution and noise floor are monitored in real-time, and the discrimination threshold is dynamically adjusted to obtain candidate defect regions and their characteristics. Different detection modes are sequentially activated, and the most sensitive excitation method is selected to confirm the defect type, density, and location. This invention adaptively adjusts laser parameters based on the quality of real-time acquired photoluminescence signals, enabling stable excitation of hidden defects under dynamic conditions. By decoupling background noise and self-absorption effects, pure defect feature signals are extracted. Dynamic adjustment of the discrimination threshold and fusion of three detection modes achieve high-confidence defect identification.

The application relates to a fitting method and device for transient absorption spectrum dynamics, belonging to the field of time-resolved spectrum. The device comprises a spectrum acquisition module, a dispersion correction module, a dynamic fitting module and an upper computer. The spectrum acquisition module is used for acquiring transient absorption spectrum data under a preset time delay sequence, so that a transient absorption spectrum data matrix is obtained. The dispersion correction module is used for generating a corrected transient absorption spectrum data matrix. The dynamic fitting module uses the corrected transient absorption spectrum data matrix and a related dynamic fitting function to fit the characteristic constant of intrinsic excited state decay dynamics. The application describes the convolution of pump light, probe light and intrinsic spectrum dynamics through the time-domain representation and fitting of the pump light and the probe light, and obtains accurate intrinsic transient absorption dynamics through a fitting model, so that the fitting of transient absorption spectrum dynamics is realized. The application can eliminate the influence of the pulse width of the pump light and the probe light on the transient absorption spectrum dynamics, and improves the fitting precision.

The invention provides an LIBS (laser-induced breakdown spectroscopy) measurement method and system based on time domain integral uncertainty correction, and relates to the field of laser-induced breakdown spectroscopy, and the method comprises the following steps: carrying out single sampling on a to-be-measured sample by using an LIBS device to obtain a time-resolved spectrum of a generated single plasma; selecting a specific wavelength, and selecting characteristic spectral line intensity data of the analyzed element at the specific wavelength under different delay times from the time-resolved spectrum; solving unknown parameters of the radiation intensity evolution function by combining an integral equation set of the radiation intensity evolution function under the specific wavelength to obtain the radiation intensity evolution function; reconstructing a curve that the radiation intensity evolves along with time under a specific wavelength, and extracting an evolution peak value of atom / ion transition radiation intensity after avoiding laser-induced plasma background radiation from the evolution curve as corrected spectral line intensity; and carrying out quantitative analysis on the analyzed element by utilizing the corrected spectral line intensity. According to the invention, the repeatability and the detection precision of the laser-induced breakdown spectroscopy are improved.

The invention discloses a milk powder adulteration qualitative and quantitative collaborative analysis method based on time-resolved LIBS (laser-induced breakdown spectroscopy). Comprising the following steps: S1, acquiring LIBS spectral data of a milk powder sample at a plurality of delay times to form a time-resolved spectral matrix; s2, performing feature extraction on the spectrum matrix to obtain a multi-scale feature vector; s3, inputting the multi-scale features into a classification branch and a regression branch based on mixed experts, outputting the probability of each adulteration type by the classification branch, weighting the concentration prediction result of each expert sub-network by the regression branch according to the probability, and outputting the final adulteration concentration; s4, carrying out end-to-end training on the model by adopting a joint loss function; and S5, outputting the adulteration type and concentration of the milk powder sample to realize qualitative and quantitative collaborative analysis. According to the method, the limitation of weak generalization ability of traditional qualitative and quantitative splitting is broken through, and the stability, precision and industrial suitability of LIBS milk powder detection in small samples and high-dimensional complex scenes are remarkably improved. And the method has good engineering implementability and popularization value.

The application discloses a kind of electric field effect download carrier recombination and diffusion process characterization method and device, belong to time-resolved spectroscopy test technical field.The method for realizing of the present application is: preset time delay sequence, time delay refers to the interval of laser emission time and image acquisition time;According to the time delay sequence of step one preset, the transient fluorescence image of sample is sequentially collected;According to transient fluorescence image, diffusion rate D is obtained by numerical method fitting, and the characterization of carrier diffusion process is realized based on diffusion rate D.The characterization device for realizing the characterization method of the electric field effect download carrier recombination and diffusion process, including pump laser, dichroic mirror, objective, sample, reflector, optical filter, plano-convex lens, gated image intensifier detector, control module, host computer and voltage source.The present application can realize the characterization of electric field effect download carrier recombination and diffusion process, and the detection window of transient fluorescence imaging is greatly expanded to the scale of seconds.

The invention discloses a high-time-resolution wide-energy-region X-ray spectrum quantitative measurement system and method. The high-time-resolution wide-energy-region X-ray spectrum quantitative measurement system and method have the beneficial effects that quantitative diagnosis of wide-energy-region (0.2 keV-5. 0keV) and high-time-resolution (lt, 40ps) X spectrum is realized by combining a height pair transmission type grating (TG), an X-ray streak camera (XSC) and a flat response radiation flow detector (FXRD), and the time resolution of the system is superior to that of an existing soft X-ray energy spectrometer (-200ps). Compared with an existing time-resolved transmission grating spectrometer, the system realizes quantitative measurement of the wide-energy-region X-ray spectrum intensity evolution process.

The invention belongs to the technical field of mineral spectral analysis, and provides an accurate characterization and quantitative analysis method for a blue calcite luminescent spectrum. According to the method, three excitation wavelengths of 265 nm, 335 nm and 405 nm are combined with a 80K-320K temperature gradient test and a time-resolved spectrum technology, manganese ions, rare earth ions and defect luminescence centers are accurately distinguished through a luminescence center recognition algorithm, accurate separation and quantification of luminescence peaks are realized by adopting a spectrum deconvolution technology, a quantitative analysis framework based on reference is established, the detection sensitivity is high, and the method is suitable for large-scale popularization and application. The quantification accuracy is gt; therefore, important technical support is provided for scientific research and application of the blue calcite.

The application provides a compact high-power ultra-short pulse optical parametric amplification device, which is sequentially provided with a glass array, a first blazed grating pair, a slit, a first mirror and a second blazed grating pair along the light path direction; the application controls femtosecond laser to pass through the ultra-thin glass array for spectral broadening, utilizes the grating pair for pulse width compression and utilizes the adjustable slit for frequency width selection, thereby realizing wide-range continuous tuning of optical parameters such as wavelength, pulse width and power of the ultrafast femtosecond laser, and being particularly suitable for high-power hundred femtosecond and sub-hundred femtosecond laser. The device can efficiently convert the incident femtosecond laser, the pulse width and the spectral bandwidth can be continuously adjusted by a large margin, and the stability of the laser output is significantly improved compared with the mode of realizing spectral broadening by using femtosecond laser through high-pressure inert gas; and the device is particularly suitable for being used as a light source parameter tuning in an ultra-high time resolution spectrum test and an ultrafast laser processing system.

A method of identifying a characteristic of a sample (124) comprising receiving time resolved spectral data obtained by exposing the sample to a pulsed excitation beam, detecting photons emitted from the sample (124) and recording a time of each photon detection from a corresponding pulse of the excitation beam; determining an estimate of Raman emissions (160) and / or fluorescence (161); and determining the characteristic from the estimate.

This invention discloses a method for preparing heterojunctions with controllable torsion angles, belonging to the field of moiré superlattice materials technology. The method first utilizes angle-dependent pump-probe time-resolved spectroscopy to measure the optical response of the lattice orientation of a two-dimensional material, determining its lattice reference orientation and marking the surface. Subsequently, a first marking material is fixed to a substrate, and a second marking material is placed on a precision rotating stage. Observation is performed using an optical microscope. The marking directions of the two materials are first made parallel to determine the initial angle, and then the stage is precisely rotated to the target angle according to a preset torsion angle. Finally, dry transfer and van der Waals bonding of the material are completed while maintaining the angle, forming a heterojunction with a preset torsion angle. This invention achieves a fundamental shift from passive selection to active design of the torsion angle, with a control accuracy better than 0.1 degrees. It eliminates the dependence on expensive equipment such as transmission electron microscopes and has the advantages of universal process applicability, clean interface, and high success rate.

The invention discloses a time-resolved metal material multi-mechanical parameter synchronous detection device and method, and belongs to the technical field of metal material mechanical property detection. The method comprises the following steps: 1, configuring sample spectrum acquisition by using a time-resolved metal material multi-mechanical parameter synchronous detection device; 2, respectively constructing a spectrum matrix Mn under different delay time; 3, sequentially carrying out saturation removal, abnormity removal, background removal and normalization on the spectrum matrix to form a sample initial feature vector; 4, respectively acquiring training set feature matrixes under different delay times, and forming training set feature input of the prediction model by adopting a variable screening and recombination mode; 5, performing multi-fold cross validation by using the randomly selected part of samples to adjust hyper-parameters so as to obtain a prediction model; the trained prediction model is used for metal mechanical parameter detection; compared with the prior art, the technical problem of low accuracy in mechanical parameter detection of the metal material is solved by adopting the time-resolved spectrum.