262 results about "Interferometry" patented technology

The invention relates to the technical field of geological engineering, and discloses a geological safety risk dynamic assessment method based on multi-source data fusion, which comprises the following specific steps: step 1, collecting and standardizing multi-source geological data; 2, performing semantic fusion and conflict resolution on the geologic features; 3, constructing a dynamic risk assessment model; 4, risk situation real-time updating and early warning are carried out; the satellite remote sensing system in the first step adopts the synthetic aperture radar interference measurement technology, the spatial resolution is better than 3 meters, the revisit period is shorter than 7 days, and the earth surface deformation monitoring precision reaches the millimeter level. Through standardized processing and semantic fusion of the multi-source geological data, the problem of heterogeneous data integration is effectively solved, the data basic quality of risk assessment is improved, a space-time coupling neural network model is adopted, nonlinear features and space-time correlation characteristics of geological risk evolution are accurately captured, and prediction precision and timeliness are improved.

The invention provides a three-dimensional flow velocity field inversion method and system based on coherence-assisted SAR adaptive offset tracking, and a storage medium, so as to improve the problem of decoherence caused by time heterogeneity in a synthetic aperture radar interferometry (InSAR) technology, and relates to the technical field of electric power engineering geological disaster monitoring. The method comprises the following steps: establishing a space-time baseline network between SAR images; obtaining coherence data after geocoding; selecting a pair of SAR images from the space-time baseline network as a reference unit, calculating an offset result through a pixel offset tracking technology for the reference unit, and determining an optimal matching window parameter of the reference unit; establishing a mapping function between coherence and optimal matching window parameters; according to the established mapping function, calculating an optimal matching window parameter of each remaining SAR image pair; and in combination with the line-of-sight average deformation rate fields of the ascending and descending rails, inverting a surface three-dimensional flow velocity deformation field of the target area through a geometric vector decomposition model.

The invention relates to the technical field of optical detection, and discloses an object surface three-dimensional topography measurement method based on optical interference, which comprises the following steps: acquiring a mixed time domain interference signal sequence in an axial scanning process; extracting seed pixels and constructing a spatial topology connectivity feature matrix; introducing fractional Fourier transform, and constructing a joint decoupling objective function containing a frequency domain nonlinear phase distortion evaluation index and a time domain physical invariant evaluation index; executing multi-stage optimization for the seed pixels, and locking a global optimal rotation angle; array self-adaptive decoupling is executed in combination with the spatial topology connectivity feature matrix, and an optimal rotation angle matrix is generated; and performing signal decoupling and reconstruction on the mixed signal, and extracting the absolute surface height of each pixel point to generate three-dimensional shape data. According to the invention, through multi-dimensional joint decoupling and spatial prior constraint, the problem of phase decoupling caused by film interference aliasing is solved, and the calculation overhead of a large-pixel array is reduced while the measurement precision is improved.

The invention relates to the technical field of synthetic aperture radar interferometry (InSAR) and deep learning, and discloses a CNN-BiGRU landslide displacement prediction method based on InSAR deformation spatial-temporal feature fusion. The method comprises the following steps: firstly, acquiring landslide area time sequence deformation displacement by utilizing an SBAS-InSAR technology, decomposing the displacement into a trend term, a season term and a noise component by adopting variational mode decomposition (VMD), fitting and predicting the trend term and a segmented polynomial through RNN, converting a one-dimensional time sequence into a time-frequency image by the season term through a Gramb angle field (GADF), extracting spatial features by combining the CNN and extracting time sequence features by a BiGRU, and calculating the landslide area time sequence deformation displacement according to the time-frequency image. Multi-modal fusion prediction is realized; and finally combining the trend term and the season term to obtain total displacement prediction. Experiments prove that RMSE, MAE and Rindexes of the method in seasonal item and total displacement prediction are all superior to those of comparison models such as BiGRU and BiLSTM, and prediction precision and reliability are remarkably improved.

The invention discloses a cross-sensor long-time-sequence InSAR deformation monitoring method and device, a medium and a product, and relates to the field of synthetic aperture radar interferometry, the method comprises the following steps: obtaining image data sets of a plurality of SAR sensors in a monitoring area, and sequentially carrying out differential interference and time sequence deformation calculation to obtain an LOS direction deformation result; geocoding all results to unify a coordinate system; screening high-coherence point targets and constructing an observation geometry unified analysis model; time information is obtained by combining the images, and a long-time-sequence earth surface deformation resolving function model after observation geometric correction is established; and further introducing a truncated singular value decomposition operator, constructing a cross-sensor long-time-sequence deformation resolving analysis model, and finally resolving to obtain a high-precision and long-time-span earth surface deformation product in the monitoring area. According to the method, the problems of rank deficiency and solution failure caused by time shortage and observation geometric difference in multi-platform InSAR data joint solution are effectively solved, and the precision and applicability of long-time-sequence deformation monitoring are remarkably improved.

A system for automatically focusing ("autofocusing") a microscope during an inner limiting membrane (ILM) peeling maneuver is configured to output low-coherence infrared (IR) light toward the eye during the maneuver. The system includes an interferometer that senses an axial distance between the microscope and ILM and outputs distance signals indicative of the sensed axial distance. An electronic control unit (ECU) is in communication with motor-driven lenses of the microscope and with an IR light source of the interferometer. Execution of the instructions causes the ECU to receive the distance signals from the interferometer. In response to the distance signals, the ECU transmits a focus control signal to the lens(es) to thereby resolve the ILM with a desired depth-of-field. The ECU automatically adjusts a focus level of the microscope on the ILM to accommodate for respiration-related movements of the patient.

Provided are a silicon-based tunable filter, laser and an optical module. The tunable laser comprises a semiconductor optical amplifier and a silicon photonic integrated chip, wherein a first coupler, a phase regulator and a tunable filter are provided on the silicon photonic integrated chip; the tunable filter comprises a flat-top band-pass filter structure, a Mach-Zehnder interferometry (MZI) structure and a micro ring resonation (MRR) structure, which are cascaded; gain light emitted by the semiconductor optical amplifier is coupled to the silicon photonic integrated chip by means of the first coupler, and a narrowband filtered optical signal is output by means of the tunable filter; and the phase of the gain light is regulated by means of the phase regulator so as to output single-peak narrowband laser light with a tunable target wavelength.

A surface deformation monitoring method and systems based on time-series InSAR (TS-InSAR) are provided. The method includes acquiring Synthetic Aperture Radar (SAR) data; performing differential interferometry; performing a robust two-tier multi-temporal InSAR method for detection of Persistent Scatterer (PS) and Distributed Scatterer (DS) candidates to acquire time series data for surface deformation monitoring; performing a variational mode decomposition (VMD) method to decompose TS-InSAR data into a plurality of components; reconstructing time series data; performing a gated recurrent unit (GRU) method; extracting trend of surface deformation; and performing continuous large-scale deformation monitoring. The InSAR-based deformation monitoring method integrates VMD and GRU, offering significant improvements in robustness and accuracy over the existing methods.

The invention provides an overall design method and system for a double-satellite double-frequency-point InSAR satellite system. The overall design method comprises the steps that the specification of a surveying and mapping product of the double-satellite double-frequency-point InSAR satellite system is determined; determining a target positioning equation of the double-satellite double-frequency-point InSAR satellite system; determining a resolving strategy of the absolute phase of the double-satellite double-frequency-point InSAR satellite system; designing double frequency points and working bandwidth of the SAR of the satellite system; distributing surveying and mapping indexes of the double-satellite double-frequency-point InSAR satellite system; designing a dual-frequency cooperative working mode of the SAR system; and designing an on-orbit working process of the double-satellite double-frequency-point InSAR satellite system. Through double-frequency cooperative imaging and full-link index distribution design under double-satellite formation, the problems of dependence of absolute phase ambiguity of traditional InSAR surveying and mapping calculation on ground control points and time decoherence of heavy-orbit interference are solved, and single-flight-pass, high-precision and uncontrolled global topographic surveying and mapping are realized. The method has the technical effects of greatly improving the self-positioning capability of the system, the surveying and mapping product quality and the development reliability.

The present invention provides an interference measurement method and apparatus that can appropriately measure the physical properties of a sample in a non-contact manner. [Solution] The interference measurement method using the interference measurement device 1 includes: a first step of obtaining a first interference waveform W1 for each optical path length difference in the first state by performing measurements while changing the optical path length difference between the first optical path P1 and the second optical path P2 in a first state in which no sample S is placed in the second optical path P2; a second step of converting the first interference waveform W1 into a first electric field amplitude waveform WE1; a third step of obtaining a second interference waveform W2 for each optical path length difference in the second state by performing measurements while changing the optical path length difference in a second state in which a sample S is placed in the second optical path P2; a fourth step of converting the second interference waveform W2 into a second electric field amplitude waveform WE2; and a fifth step of obtaining measured values ​​regarding the physical properties of the sample S based on the electric field amplitudes corresponding to the peaks of the first electric field amplitude waveform WE1 and the second electric field amplitude waveform WE2, respectively.

Provided herein is a method comprising: binding α-synuclein to a biolayer interferometry (BLI) microprobe, contacting the BLI microprobe with a biological sample, contacting the BLI microprobe with α-synuclein, and measuring an optical signal from the BLI microprobe, wherein the optical signal indicates whether α-synuclein aggregates have formed on the microprobe.

The present application relates to the field of optical interferometry, and aims at the phase distortion problem in off-axis interferometric quantitative phase imaging, and provides an interferometric microscopic phase distortion elimination method based on PACUNeXt3+ network. The method comprises the following steps: 1. using Zernike polynomials and test target pictures to simulate and generate a data set; 2. establishing and training a PACUNeXt3+ neural network model; 3. inputting the interference graph I or of the sample to be measured into the trained neural network, and outputting the background interference graph I' r corresponding to the sample without sample information; 4. using the two interference graphs I or and I' r to reconstruct the sample phase distribution φ o (x, y) without phase distortion. The present application has high precision and speed, can eliminate the secondary or high-order phase distortion in interferometric quantitative phase imaging, and has great application prospect in the field of phase imaging.

This invention relates to the fields of optical interferometry and artificial intelligence image processing, specifically to a high-precision phase extraction method for orthogonal transverse shearing interferograms based on generative multimodal AI. This method integrates the spatial texture of the interferogram with the constraints of the orthogonal shearing mathematical model through a multimodal feature fusion module, constructing a hybrid architecture of Generative Adversarial Network (GAN) and U-Net with a physical prior loss function. This achieves an end-to-end nonlinear mapping from the interferogram to the wrapped phase, and combines differential Zernike polynomial (DZF) to complete high-precision reconstruction of the absolute phase. Experimental results show that in low signal-to-noise ratio orthogonal transverse shearing interferograms, the proposed method reduces the root mean square error (RMSE) of phase extraction by 42.7% compared to the traditional DZF method, and improves the spatial resolution to λ / 100, providing an efficient and high-precision phase extraction scheme for optical wavefront detection.

This invention relates to the field of underwater acoustic signal processing and target recognition technology, and in particular to an intelligent classification method for surface and underwater targets based on a grazing angle-range domain interferometric structure. The method first constructs a standardized sample set of vertical time-recorded maps containing depth features of both surface and underwater targets through acoustic field simulation. Then, it designs and trains a multi-scale, cross-stage feature fusion classification model. This model uses multi-scale convolution operators to extract features from different receptive fields and integrates shallow and deep-layer features through a cross-stage fusion module, achieving deep mining of depth information in the interferometric structure. Finally, the trained model is used to classify unknown target data. This invention avoids the limitations of manual feature design, realizes end-to-end mapping from raw data to category decisions, and improves the accuracy and robustness of surface and underwater target classification in complex deep-sea environments.

Disclosed herein, among other things, are systems and methods for sound pressure level measurement for hearing devices. Various aspects include a method for sound pressure level measurement using self-mixing interferometry. The method includes directing a coherent light signal towards an eardrum of a user using an optical generation device, directing an audio signal towards the eardrum of the user using an audio generation device, and sensing a reflected light signal from the eardrum of the user using an optical sensor device. Displacement of the eardrum caused by the audio signal is computed using the reflected light signal, and real ear sound pressure level (SPL) at the eardrum is computed based on the displacement of the eardrum.

The invention provides an InSAR orbit phase fine modeling method combining a frequency domain and a space domain, and the method comprises the steps: 1, obtaining a synthetic aperture radar image data set of a target region, carrying out the preprocessing, and carrying out the pairwise interference, and obtaining an initial interferogram; 2, a flat ground winding phase and a terrain winding phase in the interferogram are reserved, and an orbit phase influenced by a baseline is obtained; thirdly, the azimuth fringe frequency and the distance fringe frequency of the interferogram are obtained through Fourier transform and linear frequency modulation transform, and the azimuth phase gradient and the distance phase gradient are calculated; fourthly, an orbit fine phase model is established according to the phase gradient and the space polynomial model; according to the method, the track accurate phase model combining the frequency domain and the space domain is established, linear and non-linear track phases caused by inaccurate base lines are removed at the same time under the condition that InSAR interference diagram unwrapping is not needed, and the precision of track phase error removal is improved.

This application provides an inertial measurement method and system based on atomic interferometry. The method includes: controlling a first atomic beam and a second atomic beam to exit into an interference region, and sequentially interacting with three pulse beams in the interference region to detect the corresponding momentum transfer probability signals. The exit directions of the first and second atomic beams intersect and are symmetrical about the quantization axis. The effective pulse vector directions of the three pulse beams are adjusted so that the adjusted effective pulse vector directions are opposite to those of the original three pulse beams. The first and second atomic beams are then controlled to exit into the interference region, and sequentially interact with the adjusted three pulse beams in the interference region to detect the corresponding momentum transfer probability signals. Based on the four momentum transfer probability signals, the inertial measurement result is determined. Thus, by reversing the effective pulse vector direction, the interference area is reversed, effectively suppressing noise and drift terms unrelated to the effective pulse vector direction.

State of art techniques for measurement of blood viscosity, RBC concentration and the like are in vitro methods. Embodiments of the present disclosure provide a method and system for in vivo non-invasive measurement of blood parameters using Laser Enabled Swept Frequency Acoustic Interferometry (LE-SFAI) principle. A Continuous Wave Laser diode based Photo Acoustic (CWPA) signal in frequency domain generated from laser excitation incident on a biological tissue of a subject carrying blood vessel is acquired by the ultrasound sensor and converted to a windowed time domain CWPA signal limited to two peaks. The signal characteristics such as risetime, amplitude, and time difference between first peak and the second peak are obtained to derive blood viscosity, Red Blood Corpuscles (RBC) concentration, and blood vessel diameter.

A quantitative phase contrast imaging system comprises a light source configured to generate light and to direct the light to a sample, wherein the light comprises nonlinearly polarized light; a first lens configured to receive light from the sample; a phase filter, wherein the first lens is configured to focus the light from the sample onto the phase filter, and the phase filter is configured to modulate multiple components of the nonlinearly polarized light simultaneously (e.g., geometric phase interferometry); a second lens configured to receive light from the phase filter; and a polarized camera, wherein the second lens is configured to collimate the light beam from the phase filter to the polarized camera and the polarized camera is configured to image the sample in response to the light from the phase filter. In absence of the second lens, the camera can be placed at the image plane.

Some embodiments of the present disclosure provide atom beam interferometry. MTL beams are directed to respective MTL regions along a 3D-cooled atom beam. Within each MTL region, the respective MTL beam coherently imparts photon recoil momenta to atoms of the atom beam to produce an interference signal in the atom beam. The MTL beams are switched between first and second cases providing first and second interfering trajectory paths for the atom beam, and the atom beam is continuously directed through the MTL regions while switching the MTL beams. Atoms from the atom beam are received along the first and second interfering trajectory paths at a detection region. State-dependent responses from the atoms of the atom beam are induced in the detection region to provide data of atomic states occupied by the atoms. The data of the atomic states is translated into an interferometry measurement. Related interferometers are also disclosed.

A device includes a head-mountable frame, an optical sensor subsystem mounted to the head-mountable frame and including a set of one or more SMI sensors, and a processor. Each SMI sensor is positioned to be spaced a respective distance from a skin surface of a user. The set of one or more SMI sensors is configured to emit a set of one or more beams of light. The processor is configured to operate the optical sensor subsystem to cause the set of one or more SMI sensors to emit the set of one or more beams of light toward the skin surface of the user; to receive a set of one or more SMI signals from the set of one or more SMI sensors; and to determine a respiration characteristic of the user based at least in part on the set of one or more SMI signals.

A method for compensating for grating defocusing errors in grating shearing interferometry systems involves replacing the coefficients of the Z4 and Z9 Zernike polynomials of the fitted wavefront measured after the image-plane grating has defocused with the corresponding coefficients when the image-plane grating is located at the focal plane. This refits the wavefront to achieve algorithmic compensation for the system error. Simultaneously, the method calculates the actual defocus distance of the image-plane grating, enabling mechanical compensation by adjusting the grating to the imaging focal plane. This method eliminates the defocusing error introduced by image-plane grating defocusing, improving the accuracy of grating shearing interferometry detection optical systems.

The application discloses a multi-source InSAR image building subsidence recognition method based on space-time feature fusion, and belongs to the field of synthetic aperture radar interferometry and building deformation monitoring. The method comprises the following steps: S1, obtaining radar line-of-sight deformation observation values at each structural line endpoint of a building; S2, constructing a joint adjustment function model with the three-dimensional displacement of the endpoint as a parameter; S3, introducing a structural line length invariable constraint as an adjustment strong condition; S4, iteratively adjusting and solving the optimal three-dimensional displacement solution of each endpoint; and S5, recognizing uneven subsidence according to the displacement vector difference of adjacent endpoints. The multi-source InSAR image building subsidence recognition method based on space-time feature fusion introduces the rigid geometric structure constraint of a building, reliably reverses one-dimensional observation of a radar line-of-sight into three-dimensional deformation of a building structure key point, and realizes fine recognition and quantitative analysis on uneven subsidence in the building.

This disclosure relates to the field of remote sensing and mapping technology, and provides an adaptive distributed scatterer interferometry method, apparatus, and medium for mountainous areas. The method includes: acquiring radar image data and digital elevation model (DEM) data of the target monitoring mountainous area; calculating the radar vegetation index of each pixel in the dual-polarization synthetic aperture radar (DAP) image sequence and classifying it into multiple vegetation coverage levels to obtain a vegetation coverage grading atlas; identifying statistically homogeneous pixels in each image scene under the spatial constraints of vegetation coverage levels according to the grading atlas to determine a candidate set of distributed scatterers; further, using the grading atlas, performing adaptive coherence threshold filtering on each candidate point to obtain multiple distributed scatterers; and determining the long-term surface deformation results of the mountainous area based on the multiple distributed scatterers, the DAP image sequence, and the DEM data. This embodiment effectively improves the accuracy and reliability of distributed scatterer extraction and is suitable for deformation monitoring in complex mountainous areas.

The invention discloses a topology protection Hong-Ou-Mandel interferometer based on a pi phase regulation and control grating, and belongs to the technical field of integrated photonics and quantum optics. The interferometer comprises a first waveguide and a second waveguide which are arranged side by side on a silicon dioxide substrate, and each waveguide comprises an input waveguide, a grating waveguide and an output waveguide. The two grating waveguides are provided with periodic notch grooves, and the positions of the notch grooves are symmetrically distributed about a waveguide center connecting line, so that a pi coupling phase difference is introduced between coupling in the two waveguides. The TE-TM coupling strength in the waveguides is enabled to be equal to the TE-TE coupling strength and the TM-TM coupling strength between the waveguides by adjusting the waveguide distance and the notch groove size, and the system enters a topological non-trivialness phase when delta phi is equal to pi, so that a compact topological boundary mode is formed. The structure provides an evolution path protected by topology for two-photon HOM interference, realizes interference visibility close to a theoretical limit, shows strong robustness for manufacturing errors and propagation distance changes, is obviously reduced in device size, and is suitable for high-density integrated quantum photon chips.

A system and methods for OCD metrology are provided including setting an interferometry mirror of the system at each of multiple positions z, wherein at each position the mirror reflection is Optical-Path-Difference (OPD) matched with reflection from the at least one reflective surface, and measuring interferometer spectra Imeasured, with the mirror at each of the multiple positions; then fitting the multiple measured interferometer spectra to an equation for Imeasured, to solve for non-z-dependent parameters of the equation, leaving a z-dependent function of the wave number k, having fully coherent and partially coherent terms; and removing the partially coherent terms of the function to derive a fully coherent field for characterizing the OCD structure.

The invention is based on a method of using a laser feedback interference (LFI) sensor (10), in particular a virtual retinal display (12), preferably in data glasses (14), in which at least one laser beam (16) is output by the LFI sensor (10), and in which a reflected signal (18) originating from a previously output laser beam (16) is recorded by the LFI sensor (10). According to the invention, the pulse rate of the owner of the eye (24) and / or the blood flow direction of at least one blood vessel of the eye (24) is determined from a detected reflected signal (18) of the LFI sensor (10), said reflected signal comprising a laser speckle reflection pattern (20) of the retina (22) of the eye (24).

The application discloses an InSAR atmospheric delay phase correction method along a slant range direction, comprising the following steps: S1, acquiring two SAR image subsets covering a research area and acquiring two clean water vapor data; S2, performing differential interference processing on the two SAR image subsets covering the research area to acquire differential interference phases; S3, accurately calculating atmospheric delay phases by using an atmospheric delay phase correction model; and S4, accurately obtaining real deformation of the ground along a radar line-of-sight direction. The application gives the latest weight value of the zenith path delay difference of each ground pixel on the slant range direction of the ground by correcting the sampling mode of the water vapor product along the ground distance direction, finally proposes an accurate and efficient slant range phase total delay calculation method along the ground distance, further optimizes and improves the repeat orbit synthetic aperture radar differential interferometry method, so that the measurement result is more scientific and reasonable, and therefore the application has a wide application prospect in the field of repeat orbit InSAR atmospheric phase correction.

The invention discloses a vibration drift removal and compensation method for atom interference measurement, which sequentially comprises the following steps of: carrying out atom interference continuous measurement, acquiring a voltage signal by an accelerometer, enabling the voltage signal to pass through a band-pass filter circuit, acquiring the voltage signal by a main control system, converting the voltage signal into an acceleration signal, and converting the acceleration signal into a vibration phase. The acceleration signal average value is converted into a vibration phase, vibration phase linear fitting, interference measurement period vibration phase drift removal and interference fringe fitting are carried out to obtain an interference phase, and the interference phase calculates a measured physical quantity; according to the method, data processing such as filtering, smoothing, linear fitting and deduction is carried out on signals collected by the accelerometer, suppression of time drift and temperature drift existing in relative acceleration measurement of the accelerometer is achieved, and measurement noise introduced by ground vibration is greatly reduced.

This invention discloses a self-supervised learning-based atmospheric phase compensation method for InSAR images, belonging to the field of differential interferometry (DI) technology for synthetic aperture radar. This method does not rely on external ground truth data. By establishing constraints for solving the atmospheric phase and integrating them into the network training process, it achieves self-supervised learning for atmospheric phase compensation. The method includes: constructing an atmospheric phase estimation network, which takes a time-series unwrapped phase image and related auxiliary data as input, and outputs the atmospheric phase estimation result or intermediate variables used to calculate the atmospheric phase; constructing differentiated constraint loss terms for reference points with different phase change modes based on the phase component composition of the interferometric phase; embedding physical prior constraints in both network structure and loss terms; combining various loss terms into a total loss function, and completing self-supervised training through iterative optimization to achieve atmospheric phase estimation and compensation.