173 results about "Plane wave" patented technology

The invention is suitable for the technical field of ultrasonic imaging, and provides a three-dimensional ultrasonic imaging method and system, computer equipment and a computer program product, and the method comprises the steps: transmitting a multi-angle composite plane wave sequence to a target region through a one-dimensional ultrasonic array with the frequency gradual change characteristic in the elevation direction, and receiving a reflected echo signal sequence, generating a target gray-scale image sequence corresponding to the echo signal sequence, acquiring coordinates of each ultrasonic contrast agent microbubble in each frame of gray-scale image, generating a two-dimensional coordinate set, calculating the axial half-peak full width of a point spread function region of each ultrasonic contrast agent microbubble, and calculating the axial half-peak full width of the point spread function region of each ultrasonic contrast agent microbubble; determining the coordinate of each ultrasonic contrast agent microbubble in the elevation angle direction based on the axial half-peak full width, generating an elevation angle coordinate set, and generating a three-dimensional contrast image of the target area based on the two-dimensional coordinate set and the elevation angle coordinate set. According to the method provided by the invention, the problem that three-dimensional ultrasonic imaging is limited by the surface ultrasonic array can be solved, and low-cost, simple and efficient three-dimensional ultrasonic imaging based on the one-dimensional ultrasonic array is realized.

The invention discloses an ultrafast three-dimensional wave number domain imaging method based on a row-column addressing ultrasonic array, which realizes ultrafast three-dimensional ultrasonic volume imaging by combining wave number domain image reconstruction based on row-column addressing (RCA) ultrasonic array probe data acquisition. According to the method, the three-dimensional volume imaging capability and channel number advantages of an RCA ultrasonic array probe and fewer emission times of plane wave imaging (PWI) are utilized, so that the volume acquisition rate is increased, and the data volume is reduced; according to the method, wave number domain image reconstruction is executed, rapid reconstruction of three-dimensional volume data can be realized by utilizing the calculation efficiency of fast Fourier transform, and the three-dimensional imaging requirements of high resolution and high frame rate are met. Compared with a time domain delay superposition algorithm, the method has remarkable technical advantages and is expected to be popularized and applied to medical and industrial detection scenes needing real-time three-dimensional volume imaging.

The present application relates to the technical field of optical aspheric surface, especially points to a kind of free curved surface characterization method based on CGH lens zero position compensation detection optical path, with the detection of free curved surface as the guide, based on zero position compensation detection principle, according to ray tracing method, Snell's law, diffraction principle and equal optical path principle, using the parameters required by interferometer incident wave front as plane wave, compensator as single CGH lens zero position compensation detection system indirectly characterizes free curved surface shape, by using XY polynomial and Zernike standard phase polynomial, the mathematical description of free curved surface is realized in design stage can determine its measurement scheme, and according to the characterization method self-defined a kind of aspheric surface type, called zero position free curved surface.The free curved surface characterization method improves the degree of freedom of free curved surface shape and the feasibility of zero position compensation method, reduces the detection difficulty of free curved surface shape, realizes the function of zero position free curved surface design can be detected.

This invention provides a method for rapid planar near-field measurement of large-aperture antennas, relating to the field of antenna technology. The method obtains sparse field amplitude and phase information of several sampling surfaces in the near-field radiation region of the antenna under test through large-step uniform sampling. Simultaneously, it samples a finite number of precise field amplitude and phase information points for each sampling surface and obtains the field distribution characteristics by calculating the fluctuation of the amplitude at the sampling points. Based on the sparse field amplitude and phase information and field distribution characteristics of the sampling surfaces, it uses partitioned interpolation and field distribution calibration methods to obtain the initial electric field of each sampling surface. Based on planar wave spectrum theory, iterative numerical calculations are performed on the initial electric field to recover the near-field distribution of each sampling surface. Finally, the far-field radiation characteristics of the antenna are obtained through near-field-to-far-field transformation. This invention can significantly shorten the testing time while obtaining key indicators of the antenna's far-field characteristics, including the normalized radiation pattern main lobe and first sidelobe, 3dB beamwidth, sidelobe level, and axial ratio.

The application discloses a near-field strong interference suppression method based on spherical wave deconvolution beam forming positioning, which comprises the following steps: performing fine grid division on a near-field scanning area of a linear array; performing spherical wave focusing beam forming on the near-field scanning area and two-dimensional deconvolution beam forming about distance-angle under the condition of unknown sound source position; calculating the distribution entropy characteristics of the deconvolution beam forming result in the angle dimension, and using a preset threshold to correlate the interference positioning of a target; constructing an array flow pattern matrix A of each near-field target l and generating a covariance matrix A; calculating the orthogonal complement space projection matrix of the covariance matrix A, and applying the orthogonal complement space projection matrix to the array element domain covariance matrix C to perform near-field interference suppression; using a far-field plane wave model to perform deconvolution beam forming calculation on the covariance matrix for suppressing near-field interference, so as to obtain passive detection results of the near-field strong interference suppression. The application can realize near-field interference positioning and interference suppression under the condition that the interference position is unknown.

Methods and seismic data processing apparatuses use a down-going annihilation operator to generate an image from seismic data acquired over a water-covered subsurface formation. The down-going annihilation operator is derived using a down-going wavefield and an estimated water-wave extracted from the seismic data. The down-going annihilation operator may be derived in plane-wave domain.

The invention provides a curved surface polarization torsion reflecting surface and an antenna using the same, and belongs to the technical field of antennas. The curved surface polarization torsion reflection surface comprises a curved surface dielectric plate, and a metal bottom plate and an electromagnetic metasurface which are respectively arranged on the outer side and the inner side of the curved surface dielectric plate; the electromagnetic metasurface is formed by periodically arranging a plurality of single-layer electromagnetic metasurface units. The single-layer metasurface unit with the polarization torsion function is conformal on the curved surface, so that the technical problems that a traditional multi-layer planar polarization torsion structure is complex to process, curved surface conformal is difficult, and the performance is deteriorated after conformal are solved. The reflecting surface is preferably a paraboloid, so that the incident wave polarization torsion is realized, and the spherical wave can be converted into the plane wave to improve the antenna gain. The metasurface unit keeps good cross polarization reflection performance within the wide incidence angle range of 0-40 degrees, is suitable for curved surface conformal design, can be integrally formed through 3D printing, and is easy and convenient to machine and stable in performance.

A finite size abnormal reflection super surface design and surface impedance optimization method based on integral equation, comprising the following steps: step 1: determining the size of the abnormal reflection surface unit of the actual project; step 2: obtaining the number of super surface units in the finite size direction through the finite size / super surface unit size, and forming a super surface array; step 3: dividing each individual super surface unit into impedance pieces of equal length in the finite size direction; step 4: further dividing each small impedance piece into sub-units of equal length in the finite size direction; step 5: simulating electromagnetic waves in the form of plane waves to 0° incidence of the super surface array, generating surface current, and the surface current will excite a scattering field; the scattering field reaches the ideal state in the target direction. The impedance surface proposed in the application can be designed for any large-angle abnormal reflection angle requirement and any target size, greatly improving its practicability in future application scenarios.

This application discloses an electromagnetic absorber and an electromagnetic wave absorption method. The electromagnetic absorber includes: a reflective phase gradient metasurface array, comprising a first dielectric layer, a first metal backplate layer, and multiple metal resonant units. The first dielectric layer is disposed on the upper surface of the first metal backplate layer, and the multiple metal resonant units are arrayed on the first dielectric layer. Each metal resonant unit includes n metal H-shaped structures of different sizes. The reflective phase gradient metasurface array is used to convert plane waves into surface waves. A surface plasmon polariton coupler is used to converge and absorb the energy of the converted surface waves. This application can achieve effective convergence and absorption of surface wave energy.

The present application relates to the technical field of optical aspheric surface, especially refers to a kind of splicing aspheric surface characterization method based on CGH lens zero position compensation detection optical path, with the detection of aspheric surface as the guidance, based on zero position compensation detection principle, according to ray tracing method, Snell's law, diffraction principle and equal optical path principle, using the parameters required by the zero position compensation detection system of interferometer incident wave front as plane wave, compensator as single CGH lens and diffraction surface as binary optical surface 3 or binary optical surface 4 to characterize aspheric surface surface shape, and according to the aspheric surface type defined by the characterization method, it is called zero position splicing aspheric surface.According to the splicing aspheric surface characterization method, the measurement scheme can be determined in the design stage through the mathematical description of splicing aspheric surface, which avoids the influence of stray light and projection distortion of CGH detection, reduces the detection difficulty of splicing aspheric surface surface shape, and realizes the function of zero position splicing aspheric surface design.

The application discloses a kind of illumination system and exposure equipment based on plane wave, comprising: first mirror, wavefront aberration detection module is inclined relative to light incidence direction, first mirror is used to receive light from light source and reflect light;Second mirror, for receiving the light reflected by first mirror and expanding the beam of light;Third mirror, for receiving the light reflected by second mirror and collimating the light back to the target object and reflecting light.The application realizes light path folding through the reflection path of first mirror, second mirror and third mirror, significantly shortens the axial length of illumination system, and significantly saves space.The number of structures of the three mirrors is much less than that of the conventional multi-lens group, and the positioning accuracy requirement of the mirrors is lower than the coaxiality requirement of the multi-lens, which simplifies the overall structure design and assembly process of the illumination system, and reduces the system complexity and use cost.

This invention discloses a method for obtaining the wide-angle single-station RCS of a medium target based on a compressed sensing algorithm. The steps are as follows: setting a wide-angle uniform incident plane wave illuminating the medium target; defining RWG basis functions and calculating the excitation vector for each incident angle; performing sparsification and compression on the excitation vectors respectively; generating the PMCHWT equations for the target surface and solving to obtain the compressed induced electromagnetic current matrix; recovering the original induced electromagnetic current matrix from each column of the compressed induced electromagnetic current matrix using the OMP algorithm; and calculating the radar cross section of the medium target based on the induced electromagnetic current vectors. This invention can obtain the RCS result at any angle with fewer PMCHWT equation solutions and combined with the OMP recovery algorithm, reducing the solution time for the wide-angle RCS of the medium target while ensuring accuracy.

The invention discloses a method for cooperatively detecting the curvature radius and the surface shape error of a toroidal optical element. The method comprises the following steps: S1, determining the position of a CGH compensator relative to a laser plane wave interferometer; s2, determining the position of the ring surface optical element and acquiring curvature radius data; and S3, performing zero position measurement to obtain surface shape error data of the optical surface of the ring surface optical element. The method for cooperatively detecting the curvature radius and the surface shape error of the toroidal optical element has the advantages of being few in steps, ingenious in design, capable of cooperatively detecting the curvature radius and the surface shape error of the toroidal optical element and the like.

The invention provides a frequency domain three-dimensional divergent wave ultrasonic image reconstruction method and system. The method comprises the following steps: (1) data acquisition: transmitting one or more three-dimensional divergent waves and receiving all echo signals; (2) imaging processing: performing three-dimensional Fourier transform on the received echo signal to obtain a three-dimensional frequency spectrum of the echo signal, obtaining a frequency spectrum of an image according to a mapping relation between the frequency spectrum of the echo signal and the frequency spectrum of the image after beam synthesis, then performing three-dimensional inverse Fourier transform on the frequency spectrum of the image to obtain a coordinate of the image in a plane wave space, and finally obtaining a coordinate of the image in the plane wave space; and finally, obtaining image coordinates of the Cartesian space of the divergent waves according to the spatial transformation relation. And (3) post-processing the image: sequentially performing Hilbert transform, envelope detection, scanning conversion and logarithmic compression on the image obtained in the step (2) to finally obtain an ultrasonic image. The invention provides a brand-new selectable method for the three-dimensional echocardiography technology.

The invention provides an ultrasonic plane wave multi-mode cooperative imaging method and system, and the method comprises the steps: controlling an ultrasonic probe to execute shear wave elastic imaging and sound attenuation imaging of which the mechanical index is equal to or greater than a first threshold value based on a multi-level voltage control scheme; and executing super-resolution imaging with the mechanical index smaller than or equal to a second threshold value after the super-resolution imaging is completed. The method comprises the following steps: acquiring a sound attenuation coefficient graph generated in a sound attenuation imaging process, and respectively acquiring a first super-resolution graph without contrast agent perfusion, a second super-resolution graph with contrast agent perfusion and a tissue elasticity graph generated in a shear wave elasticity imaging process based on an ultrafast plane wave technology; performing post-processing on the collected first super-resolution graph to generate a probability density graph of the tissue structure, and performing post-processing on the collected second super-resolution graph to generate a microbubble tracking speed graph; and carrying out cooperative imaging on the tissue elasticity map, the sound attenuation coefficient map, the probability density map and the velocity map. The imaging comprehensiveness and accuracy are improved, and early lesion diagnosis is facilitated.

The invention discloses a strong dispersion dielectric grating guided mode resonance optical filter insensitive to angles. The filter is based on a strong-dispersion sub-wavelength dielectric grating structure, and the resonant wavelength shows the characteristic of being insensitive to the change of an incident angle. By reducing the thickness of the grating layer and the grating line width, the angle sensitivity of the device can be further reduced. The insensitivity of the wavelength of the device to the angle mainly depends on the intrinsic dispersion characteristic of an excited optical mode in the device, that is, the frequency of the optical mode with strong dispersion changes slowly along with in-plane wave vectors, so that the change of the far-field frequency response along with the angle is obviously slowed down. Based on the principle, an angle-insensitive metasurface device can be designed by using a strong dispersion optical mode. The design method provided by the invention is not only suitable for an optical filter, but also can be popularized to other metasurface devices with strict requirements on angle sensitivity, and has wide application prospects in the fields of optical communication, hyperspectral and multispectral imaging, sensing and the like.

An angular sensitive time-of-flight position sensor device is provided and includes an array of pixels each comprising: a planar waveguide structure; a collection area with a grating pattern at a specific periodicity to couple incident light into the planar waveguide structure; at least one detector placed outside of the collection area and in a plane different from that of the planar waveguide structure; an output coupler to direct the light from planar waveguide to the at least one detector; a mask to shield the at least one detector from direct illumination; a narrow band light source that illuminates a field-of-view; a first electronics configured to detect the time-of-flight of light retroreflected, scattered, or both incident onto the position sensor and configured to provide distance ranging information; and a second electronics configured to interpret and retain time-of-flight information and configured to communicate with external electronics for system applications.

The present application belongs to the field of photoelectric precision manufacturing technology, and discloses an intelligent method for detecting and adjusting basic light waves. The whole system structure contains a detection or control unit. The relative positions of various components are obtained by the initial position and the moving distance of the components. The component position is moved by a servo motor. The light intensity or interference fringe information is received by a CCD to judge the light wave condition, and the light wave collimation state is automatically detected. The required diverging spherical wave, converging spherical wave or plane wave is obtained by adjusting the internal optical device position through a computer, and no human intervention is required. The wave surface curvature radius can be reproduced and adjusted to provide the required spherical wave or plane wave. These are all conducive to providing accurate illumination light sources for various optical systems. The analysis of the CCD interference fringes in the system, combined with the detection and control of the positions of various components, is completely analyzed and calculated by a computer program before being controlled, so as to realize the adjustment without human intervention, thereby realizing the intelligence of the instrument.

The application discloses a building steel structure weld ultrasonic nondestructive testing and flaw detection method and system, belongs to the technical field of weld detection, and the method comprises the following steps: acquiring weld surface laser point cloud data, calculating local normal direction and converting probe inclination; extracting noise amplitude sequence in a non-welding area, and constructing a noise statistics table; driving an ultrasonic array probe to generate a full matrix echo data set and a plane wave echo data set according to a scanning posture table; mapping into a full focus image and a plane wave superposition image, calculating amplitude difference to generate a fusion weight map; generating a fusion image based on the fusion weight map, performing regional segmentation by using the noise statistics table, and extracting a defect boundary coordinate table. The technical scheme of laser point cloud guided probe posture, dual-mode imaging fusion and adaptive noise segmentation can realize high-precision, automatic identification and objective quantitative evaluation of internal defects of a weld.

The invention belongs to the technical field of ultrasonic equipment, and particularly relates to an ultra-fast ultrasonic imaging method, system and equipment. In order to effectively solve the problem that ultra-fast imaging is difficult to realize in a miniaturized ultrasonic system, the complexity of the whole system is reduced by designing a sub-aperture control system for transmitting and receiving, so that the plane wave imaging design of space splicing is realized, and the ultra-fast ultrasonic imaging method is completed. The technical scheme of the invention has the advantages of low system complexity, low resource consumption during operation, high data transmission stability and rate and the like, is beneficial to the application of miniaturized ultra-fast ultrasonic imaging equipment, and has a good application prospect.

The invention provides a quantum storage structure optimization method for a plane wave basis group Hamiltonian, relates to the field of quantum calculation and quantum chemical simulation, and aims to solve storage and calculation challenges caused by huge scale of a Hamiltonian matrix in quantum calculation. Through structural analysis, double-layer index coding and structured QROM module construction, efficient loading and dynamic calling are achieved. The quantum random access memory routing module supports sub-channel loading, path compression reduces the number of control gates, and resource efficiency and flexibility are improved. The method is suitable for large-scale periodic material simulation, such as crystal structure optimization and electronic state analysis, is in seamless connection with a mainstream quantum algorithm, and remarkably reduces the circuit depth and auxiliary bit requirements.

The application discloses a millimeter wave flat plate slot array antenna with a filtering function, and relates to the technical field of radio frequency communication. The copper-based micro coaxial line-quasi-planar waveguide transition structure is connected with the staggered vertical layout cross-coupled millimeter wave filter, and is integrated with the quasi-planar waveguide feed power division network to realize a three-dimensional quasi-planar low-loss integrated feed circuit, and the feed circuit excites the high-mode flat plate slot antenna array through a coupling slot. The application utilizes the multi-layer metal plane and vertical design capability of electrochemical additive technology, breaks through the key problems of low-process-complexity low-loss interconnection integrated transition interface, low-loss miniaturized filtering structure and array antenna remaining limited special-shaped physical space integrated, and meets the actual application requirements of miniaturization and integration of the millimeter wave radio frequency communication system.

1. Name of the product in this design: Tunnel Broadcast Plane Wave Directional Loudspeaker. 2. Application of this design: Long-distance directional sound wave emission device. 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. 5. The design for which protection is sought includes color.

The invention provides an iron-sulfur isotope equilibrium fractionation factor calculation method based on a density functional theory. The iron-sulfur isotope equilibrium fractionation factor calculation method comprises the following steps: firstly, constructing initial mineral models of amorphous FeS, cubic FeS, maquinol ore, hematite, hematite and pyrite; the model is optimized through a spin polarization DFT + U method, GGA-PBE functional, OTFG ultra-soft pseudo potential, 400 eV plane wave cutoff energy and 5.0 * 10 <-7 > Hartree self-consistent field convergence standards are selected as calculation parameters, and the optimal Hubbar Ueff value and magnetic sequence arrangement of each mineral are determined; and finally, calculating the simple harmonic vibration frequency of the mineral, and deducing equilibrium fractionation factors (1000ln beta value) of Fe and S isotopes at a specific temperature. According to the method, the theoretical blank of isotope fractionation of the conversion path from amorphous FeS to pyrite is filled up, the data can be used for judging the isotope balance of minerals and tracing the mineralization process, and an important theoretical basis is provided for research on sedimentary diagenesis and ancient ocean redox.

This invention belongs to the technical field of coupling prediction methods, specifically relating to a method for predicting the coupling of UAV cables in high-intensity radiation fields based on transient electromagnetic fields. The method includes the following steps: simulating and modeling the UAV; simulating and modeling the cable; setting up the high-intensity radiation field excitation source; simulation settings; and high-intensity radiation field transient electromagnetic / circuit simulation. This invention uses a plane wave to set the incident direction and angle, sets a probe in the circuit model to monitor the core wire coupling voltage, and uses the Nyquist method to sample the excitation signal. The bidirectional coupling method obtains the coupling parameters of the UAV cable under high-intensity radiation fields, providing a basis for quantifying cable protection indicators. Furthermore, this invention constructs high-intensity radiation field signals based on VBA macro programming, allowing for customizable parameters such as rise time, pulse width, fall time, amplitude, and period of the high-intensity radiation field signal waveform, achieving numerical control and realizing numerical simulation of high-intensity radiation field signals.

The invention discloses a diffracted wave imaging method, a diffracted wave imaging device, diffracted wave imaging equipment and a medium based on Gaussian beam operators. The diffracted wave imaging method comprises the following steps: processing shot gather seismic records to obtain local data volumes and corresponding local plane waves in different directions; ray tracing is carried out at a seismic source position, and seismic wave real number travel time from the seismic source to an imaging point and a Gaussian beam propagation vector are calculated by using the seismic wave real number travel time; ray tracing is carried out at the beam center position, and seismic wave real number travel time from the beam center position to an imaging point and a Gaussian beam propagation vector are solved; calculating the real number travel time of the two-way seismic wave from the seismic source to the imaging point and then to the beam center position, picking up an amplitude value in the local plane wave according to the initial ray parameter of the beam center ray, and multiplying the result by the anti-stationary phase filter to serve as a migration imaging value of the imaging point; and all obtained migration imaging values are accumulated to finally obtain a diffracted wave imaging result based on a Gaussian beam operator.

The invention provides a portable ultrasonic imaging method based on multi-angle plane waves and a neural network, and belongs to the technical field of neural networks and ultrasonic imaging, and the method comprises the steps: obtaining multi-angle plane wave original data collected by an ultrasonic probe; screening out optimized angle combination data from the multi-angle plane wave original data through a first convolutional neural network model; transmitting the optimized angle combination data to terminal equipment; performing beam forming and image processing on the optimized angle combination data through a second convolutional neural network model in the terminal equipment to generate an ultrasonic image; and displaying the ultrasonic image through the terminal equipment. Aiming at the business scene problems that the multi-angle plane wave data processing efficiency is low and the image quality is influenced by noise and angle selection in the traditional ultrasonic imaging, the imaging quality and efficiency are obviously improved by innovatively fusing the intelligent processes of data screening, transmission and image processing.

The invention discloses a heterogeneous collaborative analysis method and system for a plane wave ultrasonic intelligent agent. The system adopts a heterogeneous double-GPU architecture, the first graphics processing unit is specially used for generating an original radio frequency signal to a multi-modal image, the second graphics processing unit is specially used for AI reasoning, and the first graphics processing unit and the second graphics processing unit realize data non-cache direct transmission through a direct memory access technology. The core of the system lies in that a computing power dynamic distribution and load control algorithm is introduced, and a computing power buffer area is constructed by actively controlling the peak load rate of a graphics processor to be below a preset threshold value. The design not only reduces the architecture delay, but also ensures that the system can immediately respond to the closed-loop feedback adjustment of the imaging parameters by using the reserved computing power when facing the complex focus analysis. In combination with multi-modal data fusion and standard section quality control, the real-time performance, high accuracy and system stability of ultrasonic diagnosis are realized.

The invention discloses a plane wave-based illumination system and exposure equipment, and the system comprises a first reflector, a wavefront aberration detection module is inclined relative to a light incident direction, and the first reflector is used for receiving light from a light source and reflecting the light; the second reflecting mirror is used for receiving the light rays reflected by the first reflecting mirror and expanding the light rays; and the third reflecting mirror is used for receiving the light reflected by the second reflecting mirror, collimating the light and then reflecting the light to a target object. Through reflection paths of the first reflector, the second reflector and the third reflector, light path folding is achieved, the axial length of the illumination system is greatly shortened, and space is remarkably saved. The number of the structures of the three reflectors is far smaller than that of a traditional multi-lens group, the positioning precision requirement of the reflectors is lower than the coaxiality requirement of multiple lenses, the overall structural design and assembly process of the lighting system are simplified, and the system complexity and the use cost are reduced.

The invention discloses a millimeter wave dual-circular polarization multi-beam antenna based on a polarization grating lens. The millimeter wave dual-circular polarization multi-beam antenna comprises a dielectric polarization grating lens and a millimeter wave + / -45-degree dual-linear polarization antenna array. According to the multi-beam antenna, a + / -45-degree dual-line polarization planar antenna array is used as a feed source and is placed on a horizontal focal plane of a dielectric polarization grating lens, and dual-circular polarization beam scanning is realized by exciting different ports of the feed source array. Each perforated column in each layer of the dielectric polarization grating lens has dielectric constants in radial gradient distribution and anisotropy in horizontal and vertical directions, and can convert + / -45-degree dual-linear polarization into dual-circular polarization while converting spherical waves into plane waves to improve antenna gain. The planar lens and the polarization grid structure are integrated, the system size is effectively reduced, + / -50-degree dual circular polarization beam scanning is achieved, the axial ratio bandwidth reaches 21.8% (24.5-30.5 GHz), and the maximum gain reaches 19.2 dBic.