Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

293 results about "Plane wave" patented technology

In physics, a plane wave is a special case of wave or field: a physical quantity whose value, at any moment, is constant over any plane that is perpendicular to a fixed direction in space.

Method for realizing acoustic vortex tunneling transmission on metasurface based on topology

The invention provides an acoustic vortex tunneling transmission method based on topology pairing metasurfaces, and the method comprises the steps: respectively arranging an absorption type metasurface and an emission type metasurface which have opposite topological charges at an inlet and an outlet of a tunneling channel, forming a pair of topology pair TPMs structures, and forming a vortex tunneling system together with a sub-wavelength channel; mode conversion between vortex waves and plane waves is achieved through multi-period fan-shaped grooves etched in the angular direction and the radial direction, and the transmission efficiency is enhanced through Fabry-Perot resonance in a sub-wavelength channel. When the length of the tunneling channel meets specific conditions, periodical adjustment of transmissivity and perfect tunneling can be achieved, and the tunneling structure has high OAM mode coupling and transmission efficiency while guaranteeing the compact structure and low material cost. The metasurface designed by the invention supports diversified acoustic vortex tunneling transmission along a straight line and a curve, and shows excellent flexibility and stability.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Three-dimensional ultrasonic imaging method and system, computer equipment and computer program product

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.
Owner:SOUTHERN UNIVERSITY OF SCIENCE AND TECHNOLOGY +1

On-line automatic bar flaw detection method and device based on full-focusing phased array technology

The invention relates to the technical field of full-focusing phased arrays, and discloses an on-line automatic bar flaw detection method and device based on a full-focusing phased array technology. According to the method, after water immersion type coupling is carried out, array elements of a concave array phased array probe are excited in a plane wave emission mode, multi-angle acoustic beams are formed, and full-matrix echo data are captured; for transverse wave detection, the sound field uniformity is improved by adopting a grouped alternate emission mechanism. Full-domain dynamic focusing is realized through coherent superposition processing, and real-time alarm and mark spraying are carried out on standard exceeding defects in combination with encoder data. The device comprises an off-line automatic calibrator, a conveying roller way, a steel splitting instrument platform, a pinch roll system, a lifting transverse moving platform, an ultrasonic detection host, a mark spraying system, a water circulation system and a PLC system, and efficient and accurate on-line bar flaw detection is achieved.
Owner:JIANGSU JINYU INTELLIGENT DETECTION SYST CO LTD

Ultrafast three-dimensional wave number domain imaging method based on row-column addressing ultrasonic array

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.
Owner:ZHEJIANG UNIV

System for measuring performance of equipment under test, and method therefor

Disclosed are a system and a method for a high-speed performance measurement. The system includes: a fixing part; a positioner for controlling the rotation of the equipment by controlling the fixing part; a measurement probe; a curved reflective plate for reflecting, in the direction of the measurement probe, an electromagnetic wave radiated by the equipment and transforming the spherical wave of the measurement probe into a plane wave at the position where the equipment is provided; an arc structure including an arc arranged to be adjacent to the fixing part; a probe set including near-filed probes arranged to be spaced predetermined intervals apart from each other on the inner side of the arc; and a control unit, which receives, through a signal analyzer, signal data corresponding to an input signal from some of near-filed probes and the measurement probe.
Owner:REPUBLIC OF KOREADIRECTOR GENERAL NAT RADIO RES AGENCY

Balun-integrated full-wave oscillator radiation unit

The utility model discloses a balun-integrated full-wave oscillator radiation unit, and aims to solve the problems that a low-frequency bowl-shaped oscillator and a high-frequency die-cast half-wave oscillator are used in the conventional high-low frequency nesting scheme, so that the requirements of miniaturization and light weight of an antenna are difficult to meet, the processing cost is extremely high, and the cost is low. And meanwhile, the high-frequency oscillator is arranged in the bowl-shaped oscillator, so that the horizontal plane wave width deformation of the high-frequency oscillator is caused, the gain is influenced, and the market demand cannot be met. The Balun-integrated full-wave oscillator radiation unit comprises a fixed support and a PCB radiation plate installed on the fixed support. The structure of the full-wave oscillator is relatively simple, assembly can be completed only by installing the single-balun integrated feed sheet in the fixing support and welding and fixing the single-balun integrated feed sheet and the PCB radiation plate, miniaturization design can be achieved through the microstrip technology, the printed circuit technology and the like due to the fact that single-face embedded coupling is adopted, the requirement of miniaturization equipment is met, machining is easy, and cost is low. The production efficiency can be greatly improved, and the production cost is reduced.
Owner:DONGGUAN YUNTONG COMM TECH CO LTD

Fourier finite difference deconvolution imaging method based on inclination angle adaptive noise suppression

The invention discloses a Fourier finite difference deconvolution imaging method based on inclination angle adaptive noise suppression, and relates to the technical field of geophysical exploration of petroleum. The method specifically comprises the following steps: designing a scattering point speed model to solve a partial point spread function of an underground space; solving a partial point spread function by a speed disturbance method; solving point spread functions of all positions of the underground space by carrying out Gaussian filtering technology and inverse distance weighted interpolation on part of the point spread functions; using a plane wave destruction method to solve the inclination angle attribute of the work area, and constructing an inclination angle self-adaptive diagonal diffusion Fourier finite difference migration method based on the inclination angle attribute to solve a high-quality initial image suitable for an inversion system; and performing multi-dimensional deconvolution in the wave number domain to obtain a final migration imaging result. According to the method, the point spread function is successfully introduced into Fourier finite difference imaging, and the resolution and deep amplitude of a conventional Fourier finite difference imaging method can be effectively improved.
Owner:CHINA UNIV OF PETROLEUM (EAST CHINA)

Rapid fault diagnosis method for programmable metasurface based on orthogonal coding space-time modulation

The invention discloses a programmable metasurface fault rapid diagnosis method based on orthogonal coding space-time modulation. The method comprises the following steps: step 1, applying independent orthogonal coding space-time modulation to each metasurface unit on a programmable metasurface to be diagnosed by adopting a time-varying signal based on orthogonal coding; 2, irradiating the programmable metasurface to be diagnosed by using a single-frequency plane wave; 3, receiving a reflection signal of the programmable metasurface to be diagnosed, and recovering each orthogonal coding channel energy from the reflection signal; step 4, according to the magnitude of the recovered orthogonal coding channel energy, determining a malfunctioning metasurface unit; when a certain unit breaks down, preset orthogonal coding modulation cannot be normally executed, so that a corresponding coding channel in a transmitting signal is lost, and therefore whether the unit corresponding to each coding channel breaks down or not can be judged by recovering energy distribution of each coding channel in a receiving signal, and accurate and efficient fault diagnosis is achieved.
Owner:SOUTHEAST UNIV

Ultrasonic plane wave inverse problem imaging optimization method and system and ultrasonic imaging device

The invention provides an ultrasonic plane wave inverse problem imaging optimization method and system and an ultrasonic imaging device, and belongs to the technical field of ultrasonic imaging, and the method comprises the steps: constructing a space coordinate system of an image in ultrasonic plane wave imaging; constructing a sampling matrix according to the space coordinate system of the image and the parameters of the transmitted ultrasonic plane waves, and weighting in combination with the directivity of the transducer element and the geometric information of the image to keep sparsity; based on the weighted sampling matrix, constructing a low-rank sparse optimization model of an ultrasonic plane wave inverse problem; and carrying out beam forming updating, nuclear norm updating and sparse item and Lagrange item updating on the low-rank sparse optimization model, and carrying out envelope detection, logarithm compression and gray mapping to obtain a final optimized ultrasonic image. According to the method, the advantage of high frame rate of plane wave imaging is fully utilized, spot textures are reserved, the imaging speed is high, meanwhile, the resolution ratio and the contrast ratio of the ultrasonic image are improved, and the imaging quality is improved.
Owner:BEIJING JINGSHENG YANMING TECHNOLOGY CO LTD

Freeform surface characterization method based on CGH lens zero position compensation detection light path

ActiveCN116734765BUsing optical meansSurface typeIncident wave
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.
Owner:SUZHOU UNIV

A method for direction estimation of a multi-element stereo hydrophone array

The present application relates to the technical field of ultra-short baseline direction measurement data processing, and particularly relates to a direction estimation method of a multi-element stereo hydrophone array. The method approximates sound waves as plane waves and establishes a mathematical relationship between time difference of arrival (TDOA) and a direction vector, takes TDOA as an observation value, calculates a direction vector estimation value according to a weighted least square method, then calculates the equivalent weight of the observation value according to an equivalent weight function, further replaces the original observation value weight array with an equivalent weight array, and recalculates the direction vector according to the weighted least square method, iteratively calculates the equivalent weight and the direction vector, until the difference between the direction vectors of two consecutive times is less than a manually set threshold, and the direction vector is output as the direction of the multi-element stereo hydrophone array. The present application can weaken the influence of the sound ray bending which is not considered in the direction estimation function model, and consider the influence of the array element spacing and the target direction on the direction estimation, thereby improving the accuracy and reliability of the direction estimation of the multi-element stereo hydrophone array.
Owner:Chinese People's Liberation Army Cyberspace Force Information Engineering University

A plane near-field fast measurement method of a large aperture antenna

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.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

A near-field strong interference suppression method based on spherical wave deconvolution beamforming positioning

ActiveCN119310553BPosition fixationSound source locationHat matrix
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.
Owner:THE 715TH RES INST OF CHINA SHIPBUILDING IND CORP

Seismic data processing using a down-going annihilation operator

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.
Owner:CGG SERVICES SAS

Curved polarization torsional reflecting surface and antenna applying same

PendingCN121965160AAvoid lamination processSimple structureAntennasDielectric plateAntenna gain
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.
Owner:THE 20TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORP

Automatic design method of antenna housing

The invention particularly relates to an automatic design method of an antenna housing, which comprises the following steps: configuring a corresponding first self-defined design parameter according to a preset application scene of a target antenna housing, and generating a corresponding first self-defined parameter file based on the first self-defined design parameter; the first custom design parameters comprise an antenna housing form, a dielectric substrate performance parameter and an antenna housing structure parameter; obtaining a second user-defined performance parameter configured by the user on the graphical user interface, and generating a corresponding second user-defined parameter file; wherein the second custom performance parameter comprises any one or a combination of any more of the following parameters: an antenna housing application frequency band, a plane wave incident angle, the thickness of each layer of dielectric material, a dielectric constant and a loss angle tangent; and in response to a trigger instruction of a user, generating corresponding relation data between the wave transmissivity and the frequency and wave transmissivity data in different polarization modes according to the second custom design parameter, and displaying the relation data and the data in the image user interface.
Owner:XIAN LEITONG SCI & TECH

An integral equation based method for designing and optimizing surface impedance of finite-size anomalous reflection metasurfaces

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.
Owner:XIDIAN UNIV

A radar target monostatic RCS fast squint method

The application discloses a radar target single-station RCS fast scanning angle method, which comprises the following steps: firstly, a triangle grid is used to divide a created radar target geometric model; secondly, an ACA algorithm is used to perform low-rank compression processing on an excitation matrix; thirdly, a double-layer mixed compression method combining an ACA algorithm and QR decomposition is used; fourthly, QR decomposition is performed on the compressed matrix, and ACA algorithm is used for re-compression; fifthly, the number of excitations required for iterative solving in the solving process is further reduced; and finally, a multilevel fast multipole method is used to combine a near-zone block diagonal preconditioning technology to construct a matrix equation, so that the number of iterative solving times of the matrix equation is greatly reduced, the solving of the matrix equation is accelerated, and the solving efficiency of the radar target single-station RCS under the excitation of a plane wave at multiple angles is improved.
Owner:XIDIAN UNIV

Ultrasonic imaging method based on single-angle plane wave and convolutional neural network

The invention provides an ultrasonic imaging method based on a single-angle plane wave and a convolutional neural network, and belongs to the technical field of neural networks and ultrasonic imaging, and the method comprises the steps: obtaining the original radio frequency data of the single-angle plane wave, and enabling all array elements of an ultrasonic probe to synchronously transmit and receive echo signals to generate the original radio frequency data; processing the original radio frequency data through a convolutional neural network model, fitting a focused wave imaging effect through supervised learning by the convolutional neural network model, and generating a target ultrasonic imaging image; and outputting a target ultrasonic imaging image, wherein the frame rate of the target ultrasonic imaging image is higher than that of traditional focused wave imaging. According to the invention, for the business scene problems of low frame rate and insufficient real-time performance of traditional focused wave imaging, high-frame-rate and high-quality ultrasonic imaging is realized by innovatively combining rapid acquisition and deep learning optimization of single-angle plane waves.
Owner:SINOPHARM GENERAL (SHENZHEN) MEDICAL IMAGING CO LTD

Method and device for extracting deep earth non-stationary diffraction fields

The present invention provides a method and device for extracting deep-earth non-stationary diffraction fields, relating to the technical field of deep-earth resource exploration. The method comprises the following steps: obtaining seismic shot gather data of deep-earth viscoelastic media; performing a reflection wave continuation non-additive transformation on the seismic shot gather data to obtain shot gather reflection continuation gather data; constructing a sparse regularization-constrained least squares problem for solving the adaptive prediction filter coefficients based on the shot gather reflection continuation gather data, a plane wave destruction filter, and an adaptive prediction filter; solving the least squares problem to obtain the target adaptive prediction filter coefficients; and extracting non-stationary diffraction wave data of deep-earth viscoelastic media based on the target adaptive prediction filter coefficients, the shot gather reflection continuation gather data, and the plane wave destruction filter. This method can effectively preserve the spectral and amplitude characteristics of the diffraction waves of deep-earth viscoelastic media, providing technical support for high-precision imaging of deep oil and gas, hot dry rocks, and other deep-layer structures.
Owner:CHINA UNIV OF MINING & TECH (BEIJING)

Electromagnetic absorber and electromagnetic absorption method

PendingCN122315359AElectromagnetic absorbersParticle physics
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.
Owner:DONGGUAN UNIV OF TECH

Speed modeling method based on three-dimensional angle gather omni-directional tomographic inversion

The invention discloses a velocity modeling method based on three-dimensional angle gather omni-directional tomographic inversion, and relates to the technical field of omni-directional tomographic inversion, and the method comprises the steps: generating a three-dimensional common reflection angle gather through omni-directional pre-stack depth migration imaging, and the three-dimensional common reflection angle gather comprises the reflection angle, the azimuth angle, the depth and other information; based on a three-dimensional common reflection angle gather, through a two-dimensional plane wave method, residual delay of each grid point is automatically picked up by utilizing finite difference of a Poisson equation; and establishing an anisotropic ray travel time matrix equation set according to the residual delays of rays with different azimuth angles, and resolving the correction amount of each depth grid point medium to obtain a new depth domain velocity model. Therefore, by adopting the velocity modeling method based on the three-dimensional angle gather omni-directional tomography inversion, the precision of a small-scale geologic body velocity model, especially a karst body in carbonate rocks, is effectively improved.
Owner:CHENGDU SHENDI TECHNOLOGY CO LTD

Three-dimensional magnetotelluric anisotropic parallel finite element forward method coupled with pml

The application relates to a three-dimensional magnetotelluric anisotropy parallel finite element forward method coupled with PML. The method comprises the following steps: determining a non-reflection condition required by PML according to the continuity condition of an electromagnetic field and the dispersion relation of a plane wave in TE and TM modes; determining the parameter form of the stable absorption performance of PML by using the relationship between the incident field and the transmission field in a lossy medium; constructing an improved wide-band PML parameter tensor according to the non-reflection condition, the parameter form of the stable absorption performance and preset characteristic parameters; and realizing finite element forward by using the improved wide-band PML parameter tensor under a preset multi-level parallel architecture to obtain a finite element forward result. The method can be accurate, efficient and widely applicable.
Owner:NAT UNIV OF DEFENSE TECH

A method for generating an ultra-long focal depth array beam

PendingCN122632456AContinuous lightGrating
The application discloses a method for generating an ultralong focal depth array beam, and belongs to the technical field of grating manufacturing. The method comprises the following steps: constructing a Bessel beam excitation phase and a circular Airy beam excitation phase, constructing a composite phase distribution according to the array Bessel beam excitation phase and the array circular Airy beam excitation phase, and encoding the composite phase distribution to a metasurface; irradiating the metasurface with a linear polarization state plane wave, so that a left-handed circular polarization component excites an array Bessel beam, and a right-handed circular polarization component excites an array circular Airy beam; the array circular Airy beam is converted into a Bessel propagation mode after self-focusing, is spliced with the array Bessel beam in an axial direction to form a continuous light field distribution, and an ultralong focal depth array beam is obtained. The method can be applied to the fields of parallel laser processing, three-dimensional microscopic imaging and microparticle manipulation, and can extend the focal depth of the array Bessel beam while keeping the transverse resolution close to the diffraction limit.
Owner:CHANGCHUN INST OF OPTICS FINE MECHANICS & PHYSICS CHINESE ACAD OF SCI

Splicing aspheric surface characterization method based on CGH lens zero position compensation detection light path

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.
Owner:SUZHOU UNIV

Chip-level electromagnetic interference positioning method and device based on dual-plane near-field sampling

The invention provides a chip-level electromagnetic interference positioning method and device based on dual-plane near-field sampling, and the method comprises the steps: obtaining spatial domain radiation data from a first sampling plane and a second sampling plane, and building a wave spectrum domain conversion relation between the two planes and a target detection plane through a plane wave spectrum expansion theory. And calculating a height calibration factor and inverting target plane field distribution, and finally forming high-resolution electromagnetic imaging. According to the method, the scanning area, the scanning step length and the scanning height difference serve as core parameters, sampling conditions are accurately constrained according to the Nyquist criterion and the cut-off frequency, and spectrum leakage and aliasing errors are effectively restrained; meanwhile, no extra calibration piece is needed, the test process is remarkably simplified, and structural dependence is eliminated.
Owner:BEIJING UNIV OF POSTS & TELECOMM

Plane wave based illumination system and exposure apparatus

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.
Owner:HYPER-OPTICS (BEIJING) TECH LTD

A method for obtaining the wide-angle RCS of a medium target based on compressed sensing algorithm

ActiveCN117572373BAddressing computational inefficienciesImprove computing efficiencyTarget surfaceEngineering
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.
Owner:XIDIAN UNIV

Method for cooperatively detecting curvature radius and surface shape error of toroidal optical element

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.
Owner:NAT UNIV OF DEFENSE TECH

Quasi-optical beamformer comprising two reflectors

ActiveUS12719176B2QuasiopticsWaveguide
A quasi-optical beamformer includes a plurality N>1 of power feeds (PF), each of the i∈[1; N] power feeds (PF) being configured to emit a respective radio-frequency beam denoted Ri, a radio-frequency transmission line (LT) fed at a first end by the power feeds and comprising at a second end a plurality of network ports (PR) that are configured to collect radio-frequency radiation, the transmission line (LT) comprising a radio-frequency waveguide (GO) that comprises at least two metal plates (PM) that are stacked so as to guide the radio-frequency beams Ri, i∈[1; N] towards the network ports (PR), the transmission line (LT) extending along a central main axis denoted axis x, a first reflector (M1) having a first centre (C1) centred on the axis x and a first effective radius of curvature and being configured to reflect the guided radio-frequency beams Ri, i∈[1; N], a second reflector (M2) having a second effective radius of curvature and being configured to reflect the radio-frequency beams (RFi) reflected by the first reflector so as to direct them towards the network ports so as to form output radio-frequency beams (RSi), the first and second effective radii of curvature and an arrangement of the power feeds (PF) with respect to the first reflector being configured so that: each of the output radio-frequency beams (RSi) is a plane wave, and a transverse amplitude distribution Ai, on the network ports (PR), of each output radio-frequency beam (RSi), is substantially identical.
Owner:THALES SA +6