9 results about "Transmission spectroscopy" patented technology

This invention discloses a highly sensitive detection method for carbendazim based on terahertz metamaterial resonance enhancement. The invention proposes a terahertz metamaterial sensor with a "+" shaped composite double-peak structure. Transmission spectra were acquired using terahertz spectroscopy, and the differences in terahertz spectra at different concentrations were investigated. Analysis revealed that the amplitude of the transmission peak in the terahertz transmission spectrum of this structure decreases with increasing carbendazim solution concentration. Data preprocessing was performed using multivariate scattering correction (MSC), feature extraction was conducted using the iterative information-preserving variable (IRIV) method, and a quantitative detection model for carbendazim terahertz transmission spectra was established based on LS-SVM. This provides a new approach for the quantitative detection of carbendazim. Experimental results show that the model has a high R-value. P The assay yielded a value of 0.9825, an RMSEP of 0.2001, and a detection limit (LOD) of 0.672 μg / ml. This invention provides a novel method for the rapid, non-destructive, and highly sensitive detection of carbendazim in food.

The application discloses a coal water-structure state recognition method based on terahertz spectroscopy, and relates to the technical field of material property characterization. The method prepares a characteristic state coal sample containing raw coal, collects a terahertz frequency band transmission spectrum and constructs a difference spectrum; three typical mechanism spectra of water-induced polarization absorption, structure scattering enhancement and cavity polarization nonlinearity are extracted through non-negative matrix decomposition to construct a frequency spectrum-mechanism-structure mapping model; the spectrum of a coal sample to be measured is collected and a difference spectrum is constructed, and after solving an activation weight vector, the difference spectrum is matched with characteristic samples to inverse the water-structure state thereof. The method can realize nondestructive and accurate recognition of the water-structure state of coal, adapt to disaster precursor warning such as water inrush in coal mines, and expand the engineering practical value of terahertz technology.

This invention discloses an alcohol detection chip and detection method based on a cascaded dual-ring resonator with dual-gradient curvature, belonging to the field of optical micro-nano sensing and integrated optics technology. This invention aims to solve the technical problems of low sensitivity, poor resolution, complex spectral analysis, and weak environmental adaptability in traditional micro-ring sensing devices, as well as the low detection accuracy of existing miniaturized equipment. The chip uses a silicon-based substrate and includes input and output waveguides, cascaded dual micro-rings, a coupling region, and two sets of miniature heating electrodes. The micro-rings employ dual-gradient waveguides with circular and Euler-circular curved structures for the inner and outer curves, respectively. The cascaded dual rings create a vernier effect, broadening the free spectral range. By adjusting the resonant wavelength through the heating electrodes, scanning detection is completed in the characteristic alcohol band around 1400nm, and high-precision alcohol measurement is achieved by combining transmission spectroscopy. This invention has a compact structure and low cost, and is suitable for rapid quantitative detection of alcohol in industrial monitoring, vehicle safety, food safety, and other scenarios.

The application discloses a kind of transmission spectrum nondestructive testing device and method, belong to fruit quality nondestructive testing field.The present application includes device shell, halogen tungsten lamp, collimating lens, pinhole diaphragm, multispectral sensor, raspberry controller, display screen and battery.Working, the light emitted by halogen tungsten lamp light source is collimated after collimating lens and passes through cherry tomato, and the light carrying cherry tomato internal quality information is filtered by pinhole diaphragm after passing through, and is received by multispectral sensor, and multispectral sensor converts optical signal into electrical signal and transmits to raspberry, and raspberry is analyzed in real time to obtain soluble solids content, hardness index and display.The present application can complete detection using separate button, uses multispectral sensor as spectral collection element, and greatly reduces the development cost of device.The present application realizes portable cherry tomato internal quality detection device, and can be used for cherry tomato key quality index on-site rapid nondestructive testing.

This invention discloses a microscopic transient angle-resolved reflection / transmission spectroscopy measurement system based on a streak camera, belonging to the field of microscopic angle-resolved spectroscopy measurement. The invention includes a reflection excitation optical path, a transmission excitation optical path, a collection optical path, and a microscopic illumination module. The reflection / transmission excitation optical path converts a pulsed laser source into a broadband pulsed white light source and focuses it onto the sample surface. The collection optical path achieves time resolution through a streak camera, angle resolution through a pinhole on the k-space plane, and wavelength or energy resolution through a grating. The microscopic illumination module illuminates the sample to determine its position. This invention can acquire transient angle-resolved spectra at different times, analyze the ultrafast dynamics of angle-resolved spectra, and simultaneously acquire information in three dimensions: time, angle, and wavelength. By analyzing the light signal from these three dimensions, it can comprehensively analyze the sample's response to the excitation light and thus determine the coupling state between light and matter in the sample.

This invention relates to the field of laser spectroscopy detection and gas analysis technology, and discloses a TDLAS gas concentration detection method and system based on a dual-view spectral attention mechanism. The method acquires the raw transmission spectrum from the TDLAS device; based on model parameters determined during the training phase, the raw transmission spectrum is normalized to obtain a normalized target spectrum; the target spectrum is tokenized using a learnable local window and injected with positional encoding information to generate a three-dimensional spectral feature cube; intraspectral attention enhancement is performed on the three-dimensional spectral feature cube using a physical prior correlation matrix to generate spectral enhancement features; interspectral cross-attention matching is performed on the three-dimensional spectral feature cube based on typical feature spectra to obtain cross-spectral fusion features; the spectral enhancement features and cross-spectral fusion features are fused to generate a final fused feature; the final fused feature is subjected to learnable weighted aggregation and multilayer perceptron mapping to obtain the concentration value of the target gas.

This invention discloses a plastic film thickness measurement system and method based on transmission spectroscopy, belonging to the field of thin film optics and optical measurement. The thickness measurement system includes a light source, an incident converging lens, a film sample, a receiving converging lens, a miniature spectrometer, and a data processing unit. The light source and the incident converging lens are connected via optical fiber. The principal optical axes of the incident and receiving converging lenses are aligned. The focal points of the incident and receiving converging lenses are adjusted to infinity. The film sample is placed between the incident and receiving converging lenses. The angle between the normal of the film sample and the principal optical axes of the incident and receiving lenses is the angle of incidence. The receiving converging lens is connected to the miniature spectrometer via optical fiber, and the miniature spectrometer is connected to the data processing unit via a USB data cable. This invention, based on the existing full-spectrum fitting method, combines the measurement of the refractive index of the film using the transmittance envelope, realizing the thickness measurement of films with unknown refractive indices.

This invention relates to the fields of analytical chemistry and semiconductor material detection technology, and discloses a method and system for determining the purity of electronic-grade anhydrous hydrogen fluoride. The method includes: introducing the sample into a low-temperature controllable gas-phase separation chamber for gradient cooling to suppress HF association; acquiring and preprocessing broadband infrared transmission spectra; dynamically subtracting HF background absorption using a differential absorption spectroscopy decoupling algorithm; and determining the type and concentration of impurities using a multi-band cross-validated impurity fingerprint identification model. The system includes a low-temperature gas-phase separation unit, an infrared excitation and acquisition unit, a data preprocessing unit, a differential decoupling calculation unit, an impurity identification unit, and a report generation unit. This invention enables the simultaneous detection of ten metallic impurities, with a detection limit of 10. ‑9 With a mole fraction and an accuracy rate exceeding 99.5%, it meets the quality control requirements for semiconductor-grade high-purity hydrogen fluoride.

This invention relates to a rapid, pretreatment-free detection method for breathable free silica on membranes based on FTIR transmission spectroscopy, belonging to the field of dust monitoring. This method establishes the RCS quality within a 5.78 mm spot diameter and the relationship between the RCS and the 800 cm⁻¹ area. ‑ ¹Standard algorithm for characteristic absorption peaks; targeting kaolinite, the most abundant interfering mineral in coal mine dust, utilizing its 915 cm⁻¹ peak... ‑ ¹The absorption peak was established at 800 cm⁻¹ ‑ ¹ An algorithm for subtracting interference. To address the non-uniform distribution of respirable dust deposited on the filter membrane surface, a piecewise function non-uniform distribution model was constructed. Based on this, a rapid algorithm was proposed that can calculate the total RCS mass of the entire filter membrane using only 10 key measurement points. The entire detection process of this invention eliminates the need for pretreatment steps such as strong acid digestion and high-temperature ashing, shortening the single detection cycle to less than 10 minutes, providing a practical and feasible technical approach for rapid on-site RCS detection in the workplace.