105 results about "Oblique incidence" patented technology

The invention provides a large-thickness electron beam weld defect repair welding spot X-ray positioning method which comprises the following steps: S1, adopting vertical transillumination for the first time to find defects; s2, selecting a heavy metal marker and arranging; s3, preliminarily positioning the relative position of the marker and the defect; s4, performing primary iterative positioning; s5, iterating for multiple times until the relative positions of the positioning marker and the defect are adjusted; s6, carrying out oblique incidence and transillumination arrangement; s7, picking off the film; s8, washing the film; s9, the position of a repair welding spot and the repair welding depth are measured and calculated; and S10, ending the detection. According to the X-ray positioning method for the repair welding spot of the large-thickness electron beam welding seam defect, a heavy metal marker selection method and an oblique incident ray defect positioning method are arranged, so that rapid and accurate positioning of repair welding of the large-thickness electron beam welding seam defect is realized.

The invention provides an oblique incidence high-efficiency broadband long-wave light splitting film, the working angle of the light splitting film is 45 degrees, an equivalent relation of double-sided design and single-sided design under oblique incidence is established through numerical calculation, 45-degree single-sided transmittance and reflectivity target values are set, and film system matching is performed by adopting a design method of alternating three refractive indexes. And then the same film system is plated on the two surfaces of the long-wave infrared substrate respectively, so that the preparation of the beam splitting film is realized. The objective of the invention is to realize high-efficiency light splitting of a long-wave infrared window in a transmittance / reflectivity ratio of 1: 1 in a wave band range of 7 [mu] m-12 [mu] m under 45-degree inclined incidence, and the light splitting film has the advantages of stable performance and small surface shape change, and is suitable for optical systems for imaging, detection and the like.

The invention discloses an intrinsic chiral super-structure surface, an angle dispersion regulation and control method and application, and belongs to the field of super-structure surfaces, the intrinsic chiral super-structure surface comprises a plurality of achiral super-atom units, a top resonator comprises two semi-circular rings in mirror symmetry, one ends of opposite sides of the two semi-circular rings are provided with notches, and the other ends of the two semi-circular rings are provided with gaps. The other ends of the opposite sides of the two semicircular rings are bent inwards to form inward protrusions. According to the intrinsic chiral super-structure surface, the angular dispersion regulation and control method and the application, the achiral super-atoms with a single mirror symmetry axis are designed, and multiple interference effects of a metal-insulating medium-metal structure are combined; the ultra-strong circular dichroism (the absolute value is about 0.8, and the single-component absorption efficiency is 98%) of terahertz waves under oblique incidence and dynamic range polarization conversion cooperatively regulated and controlled by the incident angle and the geometric dimension of the super-atom facing and inward protruding are achieved, and a multi-angle and multi-parameter adjustable innovative scheme is provided for efficient reflection type terahertz device design.

The invention discloses a negative conical wave-absorbing honeycomb, which comprises a negative conical impedance matching layer, an absorbing layer and a reflecting layer, and is characterized in that the negative conical impedance matching layer, the absorbing layer and the reflecting layer respectively comprise at least one honeycomb layer, and the honeycomb apertures of the negative conical impedance matching layer, the absorbing layer and the reflecting layer are sequentially decreased; the negative tapered impedance matching layer surface includes at least one negative tapered slot. According to the scheme of the invention, when electromagnetic waves are incident to the honeycomb, the negative conical shape design ensures that two surfaces are always in an oblique incidence state in the polarization direction, scattering of the electromagnetic waves is enhanced, reflection is reduced, impedance matching with airwaves is enhanced, the electromagnetic waves are made to be incident into the material to the greatest extent, and the electromagnetic waves are prevented from entering the material to the greatest extent. Multiple times of reflection and refraction of electromagnetic waves in the negative conical structure are increased, electromagnetic wave energy radiated out is effectively reduced, and efficient broadband absorption of the electromagnetic waves is achieved.

The invention relates to a transparent wave absorber, in particular to a wide-angle incidence insensitive ultra-wideband transparent wave absorber based on slit enhancement. The invention aims to solve the problems that an existing wave absorber is insensitive to large-angle oblique incidence of a radio frequency electromagnetic field, and inherent contradiction exists between low-thickness design and low-frequency absorption performance of the wave absorber. The transparent wave absorber is composed of N * M wave absorber units in an array. Each wave absorber unit is composed of a horizontal transparent conductive film and two vertical transparent conductive films. And the transparent conductive film is etched on the surface of the vertical transparent conductive film to form one or more strip slit non-conductive areas. The invention is used for the wide-angle incidence insensitive ultra-wideband transparent wave absorber based on slit enhancement.

The invention discloses an airborne dynamic imaging-oriented image quality enhancement calculation processing system and a method thereof, and relates to the technical field of calculation optics. The system comprises an illumination module, a collimation module, a confocal module, a beam splitting module, an angle selection filtering module and an imaging module. The angle selection filtering module changes the incident angle of a light beam through physical movement or rotation, so that the angle selection filtering module excites a Berman mode in a near-zero dielectric constant double-layer film, and real-time switching between normal incidence low-pass denoising and oblique incidence high-pass sharpening is achieved. According to the invention, switching of two typical image processing functions can be realized only through incident angle adjustment without introducing an electrical regulation and control element, so that sharpening and denoising function integration is realized in a single optical structure, and the system has millisecond-level angle switching, low power consumption and a compact linear folded optical path, and is suitable for airborne high-speed imaging.

The invention relates to a pointed cone for optimizing large-angle oblique incidence wave-absorbing performance, which comprises a cone body and a magnetic loss interlayer, the magnetic loss interlayer is arranged at the bottom of the cone body, and the cone body is integrally formed by a foamed conductive mixture. The microwave anechoic chamber has the advantages that the low-frequency large-angle oblique incidence performance of the wave-absorbing pointed cone can be remarkably optimized, then the reflection level of a low-frequency quiet zone of the anechoic chamber is improved, and the testing capacity and testing precision of the microwave anechoic chamber are remarkably improved.

The invention discloses a low-frequency wide-angle light 3D (three-dimensional) metamaterial wave-absorbing structure. The wave-absorbing structure can realize a broadband wave-absorbing function with an average reflectivity of less than-10 dB in a frequency band of 0.5-2 GHz. The structural unit is composed of a planar resonant structure and a composite three-dimensional frame resonant structure, and the wave-absorbing structure is obtained by periodically arraying the unit structure. The wave-absorbing structure has the advantages of light weight, low-frequency broadband, excellent oblique incidence performance and the like, so that the wave-absorbing structure has a wide application prospect in the aspects of target stealth and electromagnetic protection.

The invention relates to the technical field of intelligent surface defect identification of an intelligent sensing detection and optical scattering method, and discloses a yoga mat surface defect automatic identification method based on an intelligent sensor. Establishing a two-dimensional coordinate and a discrete sampling array on the surface of a measured object, and unifying an installation posture; scanning the scattering intensity of each point according to a multi-angle sequence under fixed oblique incidence, and checking the integrity and the range; summarizing according to fixed angle weights to form an angular spectrum value matrix; carrying out point-by-point difference on the defect-free reference matrix to obtain a residual error, carrying out difference synthesis along rows and columns to obtain mutation intensity, and constructing a matrix; generating candidate anomalies according to a reference mutation statistics set threshold value; a connected domain is extracted on the grid in a four-adjacent mode, insufficient area is eliminated, and the center and the area are calculated; and outputting the number, the position and the area of the defects and performing visual marking.

The invention discloses a method for correcting an error introduced by oblique incidence of light in aspheric surface interference detection, which relates to the technical field of optical precision measurement and comprises the following steps of: constructing an interference measurement system, and obtaining surface shape error distribution of an aspheric surface to be measured; constructing a corresponding geometrical optical model according to actual space layout parameters of an interference measurement system, and calculating a mapping relation between theoretical space coordinates of an interference measurement result and an illegal oblique incidence angle of a light beam; pixel coordinates of the interference measurement result are converted into theoretical space coordinates, and the oblique incidence angle of each sampling point of the actual surface shape data on the aspheric surface to be measured is calculated through an interpolation algorithm based on the mapping relation; and finally, through the relationship between the surface shape error during oblique incidence and normal incidence and the oblique incidence angle, completing the correction of the light oblique incidence introduction error in the to-be-detected aspheric interference detection. According to the method, the problem of errors caused by oblique incidence of light rays in the interference measurement process of the aspheric element is solved, and the detection precision is remarkably improved.

Variable-angle ellipsometry is performed using a high speed polarization state modulator, a photodetector, and a digital micromirror device or spinning disk to encode the angle of incidence of light with a high sampling rate in a time domain or frequency domain. A variable-angle ellipsometer uses a high speed, axially stationary polarization state modulator, such as a photoelastic modulator, and a high speed detector, such as a photodiode, for high speed data acquisition. To acquire data at a plurality of incident angles, a lens is used to generate a large incident angle distribution along an optical axis that is at an oblique angle of incidence and discrete or combinations of incident angles of light are selected in a sequence in the time domain or modulated over a plurality of incident angles in the frequency domain.

Methods and devices relating to volumetric meta-optic structures. A method involves computationally designing a three-dimensional refractive index profile using an adjoint-based optimization process. The process optimizes for sorting light based on wavelength or polarization at specific oblique incidence angles and accounts for source divergence using Gaussian beam simulations. A mode overlap figure of merit is employed, optionally including terms to minimize crosstalk. Fabrication constraints like material binarization and minimum feature size are handled via differentiable filters. Physical crosstalk barriers may optionally be modeled during optimization. The resulting optimized profile defines a manufacturable multi-layer structure comprising patterned dielectric materials configured to perform the target sorting function efficiently under the specified oblique angle conditions. An array of such devices, potentially comprising structurally distinct elements optimized for different angles, can be integrated with an image sensor.

The invention provides a method for realizing ultra-high-speed translation of a Bessel beam by using double acousto-optic modulation elements, which is characterized in that the displacement in the x-axis direction and the displacement in the y-axis direction are changed at a high speed by quickly switching radio frequencies f1 and f2, so that ultra-high-speed punching on the surface of a workpiece is realized; meanwhile, each hole has excellent morphology consistency due to vertical incidence, so that the problem of hole shape distortion caused by inclined incidence at the scanning edge of a traditional galvanometer is avoided; that is to say, the all-solid-state diffractive optical element is adopted, no mechanical moving part exists, the limitation of mechanical inertia is completely eliminated, the response time of light beam displacement only depends on the change speed of a driving signal and the establishment time of the diffraction effect, the MHz-level control effect can be easily achieved, and the speed is several orders of magnitude faster than that of a traditional galvanometer. The method is especially suitable for application scenes such as laser processing, optical tweezers, confocal microscopic imaging and high-speed optical switches.

This application relates to the field of tunnel construction safety monitoring technology, and discloses an intelligent identification method for water seepage risk at the tunnel face in water-rich clay layers. This method controls an active infrared excitation module to project radiation in an oblique incidence manner, uses polarization imaging to acquire sequences and calculates Stokes vectors; calculates the degree of linear polarization based on the Stokes vectors and performs threshold segmentation to generate a water film distribution mask; uses the Stokes vectors to construct a polarization angle field reflecting local normal changes as texture features, solves the optical flow constraint equation to obtain the instantaneous velocity field; performs frequency domain transformation on the velocity field, extracts the proportion of low-frequency creep energy through power spectral density analysis, and determines the soil rheological softening factor; finally, combines the water film distribution, rheological softening factor, and instantaneous velocity field to construct a mudslide risk index. This invention utilizes polarization texture reconstruction to solve the problem of weak texture tracking and eliminates elastic vibration interference through frequency domain energy decoupling, effectively improving the accuracy of mudslide risk identification.

The invention relates to the technical field of ultrasonic phased array nondestructive testing, and discloses a metal pipe inner wall defect ultrasonic phased array detection probe and a metal pipe inner wall defect ultrasonic phased array detection method, the probe comprises an array transducer and a wedge block, the array transducer is connected with the wedge block through a connector, and the curvature radius of the end face of the bottom of the wedge block is the same as that of a metal pipe. The curvature of the end part of the probe provided by the invention is the same as that of the outer diameter of the pipe, so that good acoustic coupling can be realized, an oblique incidence sound beam forming a certain angle with the radial direction of a detected object can be formed, and ultrasonic waves can obliquely enter the side surface of a defect; the full-focus algorithm is adopted for imaging in the axial direction of the pipe, the detection sensitivity of inner wall shallow surface defects can be effectively improved, and the detection efficiency and reliability are improved.

The utility model is applicable to the field of optical detection, and provides a double-light-source oblique incidence semiconductor wafer surface quality detection system, which is characterized in that laser of a first laser sequentially passes through a spectroscope, a polaroid, a first convex lens, a diaphragm module and a second convex lens, and obliquely enters the surface of a semiconductor wafer to be detected; and laser of the second laser sequentially passes through the spectroscope, the polaroid, the first convex lens, the diaphragm module and the second convex lens, and obliquely enters the surface of the semiconductor wafer to be measured. The existing optical detection has the defects of small detection field of view, low diffraction resolution and difficulty in positioning, while the characteristics of two detection technologies, namely photoluminescence detection and angle resolution scattering detection, are combined, so that the two detection results can be simply and quickly obtained; and the defect detection of the surface and the subsurface of the semiconductor wafer sample and the quality evaluation detection of the surface roughness are completed.

This invention provides a method for measuring dielectric constant based on oblique incidence light reflection difference technology. The probe light emitted by the laser 1 is converted into p-polarized light by the polarizer 2, and then modulated into p-polarized light and s-polarized light by the photoelastic modulator 3. The p-polarized light and s-polarized light are emitted alternately at a frequency of 50 kHz, and after passing through the phase shifter 4, a fixed phase difference is generated. Then, the light is focused by the first lens 5 and obliquely incident on the surface of the sample 6 to be tested, with the incident range between 50° and 60°. The signal light reflected from the surface of the sample 6 to be tested is incident on the analyzer 9 after passing through the second lens 8. The analyzer 9 is used to zero the fundamental frequency signal of the system. The signal light after passing through the analyzer 9 is absorbed by the photodetector 10 and converted into an electrical signal. The electrical signal is demodulated by the first lock-in amplifier 11 and the second lock-in amplifier 12 into a DC signal, a fundamental frequency signal I (Ω), and a harmonic signal I (2Ω). The demodulated signal is acquired and processed by the data acquisition and processing unit 13.

The present application relates to a kind of optical detection systems with full-angle oblique incidence dark field illumination system, belong to wafer defect detection technical field, especially to full-angle oblique incidence dark field illumination system optical detection system.The optical detection system provided by the present application, by the combination of first cone lens and second cone lens, collimate incident laser beam as parallel annular light beam, then realize full-angle oblique incidence dark field illumination by annular reflector and annular focusing system, fundamentally overcome the problems of existing single light source directional sensitivity and high precision of installation and adjustment of divergent annular light beam, poor expansibility, while ensuring the advantages of dark field high contrast, high precision and non-destructive testing, significantly improve system detection sensitivity, installation and adjustment convenience and function expansion capability.

The application provides a kind of oblique incidence high-efficiency broadband long-wave light splitting film, the working angle of the light splitting film is 45°, the equivalent relationship of double-sided design and single-sided design under oblique incidence is established by numerical calculation, the target values of 45° single-sided transmittance and reflectivity are set, three kinds of refractive index alternating design methods are used for film system matching, the film system structure design optimization is completed, then the same film system is coated on the two sides of long-wave infrared substrate respectively, and the preparation of the light splitting film is realized. The purpose of the application is to realize the high-efficiency splitting of long-wave infrared window in the wavelength range of 7-12 μm with transmittance / reflectivity of 1:1 under 45° oblique incidence. The light splitting film has stable performance, small surface shape change and is suitable for optical systems such as imaging and detection.

The application discloses a kind of round bar piece ultrasonic testing methods, it is for the round bar piece of diameter not more than 12mm, comprising: selecting contrast sample;Radial in contrast sample is opened as artificial reflector along the direction of hole;Control probe so that incident sound wave is produced pure transverse wave by axial oblique incidence of contrast sample;Adjust the incidence angle and sensitivity gain of probe, so that the wave height of secondary reflected sound wave of artificial reflector is not lower than set threshold, to determine detection sensitivity and the optimum incidence angle of probe;Control ultrasonic wave is obliquely incident along the axis of contrast sample and the bar piece to be examined, control relative helical linear motion between probe and corresponding bar piece, and obtain corresponding ultrasonic reflection signal;According to the ultrasonic reflection signal of contrast sample and the bar piece to be examined obtained is compared to obtain the organization state of the bar piece to be examined.The application can realize the measurement and evaluation of the grain organization state inside round bar piece under the premise of not destroying material structure.

The invention relates to the field of optical detection instruments, and discloses a method and device for detecting geometric parameters of an optical fiber bundle end face, and the method comprises the steps: controlling light emitted by a light source to obliquely enter a to-be-detected optical fiber bundle at a preset angle and optimal illuminance; performing convolution operation on pixel points at different pixel positions in the end face image of the to-be-detected optical fiber bundle by adopting different convolution kernels to generate a gradient map; extracting an edge image of the gradient map, and performing ellipse fitting and circle fitting to obtain an ellipse parameter and a circle parameter corresponding to the fitted image; and geometric parameters of the to-be-detected optical fiber bundle are calculated. According to the method, a common illumination light source is adopted and obliquely irradiates the cladding and the surface of the coating layer, so that geometric parameter detection can be carried out on the optical fiber with the coating layer and the cladding layer, and meanwhile, specific convolution parameters, light source brightness, an oblique incidence angle adjusting method and the like in an image edge extraction algorithm are optimized; the device can adapt to optical fiber bundles with different lengths and different transmittances, and the detection efficiency and accuracy are improved.

The present invention discloses a prism-based light source integrated super-resolution microscopy chip and an imaging method thereof, relating to the field of super-resolution microscopy. Based on a bulk high-refractive-index substrate material, a sample area is provided at the center of its upper surface, and multiple circles of prisms with different angles are provided on its lower surface. LEDs are respectively placed on the sides of the prisms, and then the positive and negative electrodes of the LEDs are integrated onto a PCB board, and the on / off of the LEDs is controlled by a single-chip microcomputer. Compared with the super-resolution microscopy imaging system with an external optical path, integrating the light source onto the super-resolution microscopy chip can achieve miniaturization and portability of super-resolution imaging, which is convenient for medical diagnosis and scientific research analysis in resource-scarce areas. Compared with traditional Fourier ptychography microscopy (FPM), using prisms can increase the light intensity, signal-to-noise ratio and oblique incidence range of the obliquely incident light source, introduce evanescent waves with a larger transverse wave vector, and effectively improve the imaging quality and resolution.

The present invention discloses an electromagnetic wave finite-difference time-domain (FDTD) method and system based on anisotropic media conditions, relating to the field of electromagnetic detection. Starting from Maxwell's equations, the method involves the constitutive relationship of the medium in tensor representation, which is given anisotropic properties. The method creatively introduces transverse wave vector parameters into the classic one-dimensional FDTD method, replacing the transverse partial derivatives in Maxwell's equations that do not belong to the propagation direction with the corresponding transverse wave vector parameters. This method can realize a one-dimensional solution for two-dimensional or three-dimensional electromagnetic problems. By setting the corresponding transverse wave vector parameters, the field intensity distribution of the electromagnetic wave can also be calculated under different conditions of normal incidence or oblique incidence.

The invention discloses a system and a method for measuring the target landing speed of a dynamic explosion oblique incidence fragment, and solves the problem that the existing fragment speed measurement method is difficult to be suitable for a dynamic explosion fragment speed measurement scene with a severe environment and an uncertain track. The system specifically comprises a projectile body coordinate resolving module, a double-layer target breaking assembly, a distributed time measuring module, a real-time dynamic positioning instrument and a terminal data processing module. The output end of the projectile body coordinate resolving module is connected with the input end of the terminal data processing module; the output end of the double-layer target breaking assembly is connected with the input end of the distributed time measurement module, and the target surface is in a regular shape; the output end of the distributed time measurement module is connected with the input end of the terminal data processing module; and the output end of the real-time dynamic positioning instrument is connected with the input end of the terminal data processing module. According to the invention, the vertical component of the fragment targeting speed is measured through the low-cost broken target, and the incident angle of the fragment at each point is measured by using the high-speed camera, so that the low-cost measurement of the multi-point oblique incidence fragment targeting speed is realized.

This invention belongs to the field of two-dimensional lateral offset measurement technology, and provides a method for synchronous measurement of two-dimensional displacement of metasurfaces based on quasi-continuous domain bound states. The method includes: acquiring a metasurface lattice sample containing dual markers; determining the band structure of the quasi-continuous domain bound states and its corresponding resonant electric field distribution through electromagnetic field simulation; determining the correlation between the normalized coupling amplitude component and the overall bias vector direction through electromagnetic field simulation; establishing a multi-solution correspondence between the incident light polarization direction and the overall bias direction; determining a unique overall bias direction from the multi-solution correspondence based on the chiral spectral differences and full width at half maximum (FWHM) response exhibited by the dual markers under oblique incidence of circularly polarized light; and calculating the two-dimensional overlay error by combining the determined overall bias direction with the preset artificial bias information. Compared with traditional methods, this application achieves synchronous measurement of two-dimensional displacement in characterizing overlay errors in photolithography processes.

The application discloses a kind of rotary body parts crack defect single-side ultrasonic oblique incidence full coverage detection method, belong to the field of measurement and control, the implementation steps of this method include: the crack occurrence area of the step root of rotary body parts is divided into two adjacent regions A and region B;Ultrasonic wave is obliquely incident from the end face of one end of rotary body parts, so that the refracted transverse wave only propagates between the two end faces of rotary body parts, and the crack in region A is detected;Ultrasonic wave is obliquely incident from the same end of rotary body parts, so that the refracted transverse wave propagates using the step, and the crack in region B is detected.This method ingeniously utilizes the structure of the boss itself, so that only ultrasonic oblique incidence from one end of rotary body parts can detect the cracks of all angles at the step root of both ends of rotary body parts, improve the detection efficiency, and reduce the labor intensity.

The application discloses a kind of applied to layered stratum seismic motion oblique incidence three-dimensional modeling input method, belong to civil engineering technical field.The method includes the following steps: S1, modeling to each layer stratum;S2, under reflection and transmission, calculate time delay and amplitude ratio;S3, calculate model boundary point parameter;S4, to model parameter is assigned value.The application adopts the above-mentioned one applied to layered stratum seismic motion oblique incidence three-dimensional modeling input method, and the seismic motion input under layered stratum is more accurate, reduces the use of parameter on seismic wave propagation path, establishes layered stratum seismic motion input method, provides effective support for near-fault underground structure seismic motion response analysis, with very strong practicality.

The invention discloses a construction method and device of an angle-stable FSS based on high-order mode regulation and control, and the method specifically comprises the steps: decomposing the scattering of a structure into the superposition of different orthogonal characteristic modes, building a theoretical model of correlation structure reflection, transmission coefficients and modal behaviors, and converting the problem of eliminating the high-order resonance of the structure into the problem of regulating and controlling the high-order mode of the structure; obtaining a miniaturized FSS through joint simulation, and judging whether the structure has high-order resonance under the condition of oblique incidence; for a miniaturized structure with high-order resonance, CMA is analyzed through a characteristic mode, and a lumped element is loaded in the structure or the structure is adjusted to block characteristic current distribution to regulate and control a high-order mode, so that the influence of the high-order resonance on the angle stability of the FSS is eliminated; and finally determining a target structure of the angle-stable FSS by using a distributed capacitance-inductance equivalent lumped element. The high-efficiency structural design of the angle-stable FSS is realized by taking application requirements as guidance.

The invention provides a well cementation quality evaluation and annulus medium propagation velocity determination method and device, and belongs to the field of well cementation quality evaluation.The determination method comprises the steps that waveform data received by a current depth point at different orientations are obtained based on oblique incidence ultrasonic logging, and the waveform data are obtained; the waveform data comprises full-wave waveforms of Lamb waves received by receivers located at different well depths; determining the average propagation time of the reflected wave corresponding to the current depth point in the annulus medium based on the waveform data received by the current depth point at different orientations; and based on the logging parameters and the average propagation time corresponding to the current depth point, determining an annular medium propagation speed corresponding to the current depth point. According to the method provided by the invention, the cement loss in the direction can be identified by independently depending on the propagation velocity of the annulus medium, so that the first-interface and second-interface evaluation of the well cementation quality is realized.