76 results about "Phase map" patented technology

The invention relates to the technical field of optical precision interference measurement, in particular to a correction method for projection distortion detection of a primary mirror of a dynamic interferometer and a related product, and the method comprises the steps: obtaining a first coordinate and a second coordinate; determining a zero distortion point; obtaining an ideal imaging point set and an actual mapping point set after system projection through ray tracing; fitting to obtain a distortion function representing the distortion of the optical system; performing point-by-point correction on a phase diagram obtained by interference measurement, mapping pixel coordinates of the phase diagram into workpiece coordinates, obtaining interference measurement data corresponding to the actual surface of the primary mirror, and completing distortion correction; according to the method for correcting the surface shape projection distortion during interference measurement of the high-precision primary mirror of the large-aperture dynamic interferometer, the problem that in the process of assembling, repairing and developing the large-aperture Twyman type dynamic interferometer, the projection distortion effect of a detection system causes the loss of an accurate matching relation between a workpiece coordinate system and a detection coordinate system is solved.

The invention discloses a light field display method and system with holography as a representation medium, and the method comprises the following steps: S1, collecting a multi-view image of a target scene, carrying out the coding of the multi-view image, and generating a light field tensor containing space and angle information; s2, mapping the light field tensor in the step S1 into a two-dimensional space phase diagram; s3, converting the two-dimensional space phase diagram in the step S2 into a modulation diagram used for driving a spatial light modulator; and S4, driving the spatial light modulator to perform light wavefront modulation according to the modulation graph in the step S3, and reproducing the image of the target scene through optical diffraction. According to the invention, integration from dynamic scene information acquisition to high-quality three-dimensional image reproduction is realized, a low-redundancy and high-fidelity processing link is realized, and the efficiency and quality of holographic display are greatly improved.

The invention relates to a speckle interferometric phase diagram filtering method based on a conditional diffusion model, and belongs to the technical field of optical measurement. The method comprises the following steps: S1, obtaining training data: generating or collecting multiple groups of paired speckle interferometric phase diagrams including noisy speckle interferometric phase diagrams and corresponding denoising reference phase diagrams; s2, constructing a conditional diffusion model; S3, training the conditional diffusion model: training the diffusion model in a supervision mode; and S4, taking the to-be-processed phase diagram as a conditional image, and generating a denoised phase diagram through a back diffusion process. According to the invention, the noise processing accuracy of the phase diagram in laser speckle interference measurement can be improved.

Embodiments of the present application provide a deep learning-based phase unwrapping method and apparatus, a device, and a medium. The method comprises: acquiring a wrapped phase map; and inputting the wrapped phase map into a pre-trained deep learning network model and performing phase unwrapping, such that the deep learning network model outputs, on the basis of a non-linear mapping relationship between wrapped phases and absolute phases, an absolute phase map corresponding to the wrapped phase map, wherein the deep learning network model adopts a U-Net framework and comprises an encoder, a decoder, a deep-supervision feature fusion module, and an atrous spatial pooling pyramid module, and the encoder and the decoder comprise Inception modules. On this basis, even in high-noise environments and in the presence of phase discontinuity, the embodiments of the present application enable a trained deep learning network model to predict a high-quality absolute phase map in just one step, thereby achieving accurate phase unwrapping.

This invention discloses a three-dimensional contour measurement method and apparatus based on multi-projection gratings, relating to the field of three-dimensional topography measurement technology. The method includes: obtaining intrinsic and extrinsic parameters through calibration; projecting a set of speckle patterns; preliminarily analyzing the surface topography gradient of the object to determine a non-uniform spatial frequency sequence; sequentially projecting and acquiring multiple sets of phase-shifting grating patterns, and calculating the wrapping phase map corresponding to each frequency; for the same pixel, based on its reliability assessment in wrapping phase maps at different frequencies, assigning confidence weights to the phase values ​​of each frequency, and calculating and optimizing the phase map and the corresponding fused confidence map; calculating gradient information and combining it with the fused confidence map to perform region division, and executing a region-guided path consistency verification unfolding algorithm to obtain the absolute phase; converting the absolute phase into three-dimensional point cloud coordinates of the object surface. This application aims to solve the problems of complex topography, discontinuities, and noise easily leading to unfolding path errors and order jumps during phase unfolding.

The present application relates to the field of information optics, more particularly, to a spatial structure vertical focal field generation method and system. The present application provides a spatial structure vertical focal field generation method, according to the constructed phase map of the spatial structure vertical focal field, the incident light beam is modulated into a cylindrical wave light beam at the light beam modulation, and then the cylindrical wave light beam is focused to generate a spatial structure vertical focal field. Wherein, the phase map only needs to be calculated according to the superposition of the column lens phase or the column lens phase and the flash grid phase, and the calculation amount and calculation time are obviously reduced compared with the iterative calculation of the existing method. The present application solves the problems of large calculation amount and long time consumption of the existing method for generating a spatial structure vertical focal field.

The application relates to a kind of quantitative imaging methods of living cells based on digital holographic microscopic sequential displacement aberration correction, and belongs to the field of optical measurement, comprising: collecting three holograms by sequentially displacing living cells; obtaining three original phase maps by phase demodulation; obtaining total mask map; sequentially displacing phase map in reverse direction; performing difference calculation to obtain global phase system aberration difference data; obtaining local system aberration difference data by using total mask map; performing difference processing on Chebyshev polynomial to obtain local polynomial difference data by using total mask map; fitting global system aberration by calculating corresponding coefficients from difference data; subtracting global system aberration from three original phase maps to obtain phase map of living cells after aberration correction. The application realizes high-precision quantitative phase imaging of living cells while retaining high-frequency information, has excellent displacement distance robustness, does not need to be equipped with high-precision displacement mechanism, and greatly reduces the hardware cost of measurement system.

A composite material gas cylinder layering defect displacement prediction method based on deep learning and laser shearing speckle interference comprises the following steps: constructing a training data set combining simulation data and experimental data, generating the simulation data based on a shearing speckle interference imaging principle, and combining the experimental data acquired by an experiment to predict the layering defect displacement of a composite material gas cylinder. Constructing a mixed data set containing a wrapped phase diagram and an out-of-plane displacement diagram; constructing a deep convolutional neural network fused with an attention mechanism, and extracting displacement features from high-frequency stripes: starting from an input layer, sequentially connecting an encoder path, a bottleneck layer, a decoder path and an output layer; constructing a composite loss function and training the network, and constructing a composite loss function comprising a pixel-level error constraint and a gradient consistency constraint; and utilizing the trained deep learning neural network to predict out-of-plane displacement response at the layering defect of the gas cylinder. According to the method, the problems of image distortion, data missing and the like caused by a traditional phase unwrapping algorithm are effectively solved, and the out-of-plane displacement field can be accurately, smoothly and continuously reconstructed.

This application discloses a 3D imaging method and system based on structured light phase measurement, relating to the field of 3D imaging technology. The method includes: calibrating a structured light measurement system to obtain intrinsic and extrinsic parameters, and determining the effective measurement depth range and the corresponding effective absolute phase interval; controlling a projector to project a preset sinusoidal fringe pattern onto the measured scene, acquiring a deformed fringe image modulated by the surface of the measured object, and obtaining a wrapping phase map; calculating the initial fringe order of each pixel based on the effective measurement depth range using a frequency domain order-based fringe order no-neighborhood solution algorithm; performing no-neighborhood verification and error correction on the initial fringe order based on the effective absolute phase interval using an order self-verification and error correction algorithm to obtain the final fringe order; and calculating the absolute phase map of the entire field of view based on the wrapping phase map and the final fringe order, and converting the point cloud data. This application aims to solve the technical problem of existing spatial phase unfolding techniques relying on the continuity of adjacent pixels.

The application belongs to the technical field of optical three-dimensional measurement, and discloses a two-division iteration sub-pixel matching method and system for phase structured light three-dimensional measurement, which comprises the following steps: obtaining a phase map; performing legality marking and pixel-level initial matching on the phase map; determining a sub-pixel search area based on the pixel-level initial matching; and performing sub-pixel matching point search based on the sub-pixel search area by using a two-division iteration method to obtain a sub-pixel matching point. The application can improve the precision of binocular matching in phase structured light three-dimensional measurement, thereby improving the precision of three-dimensional reconstruction.

The invention discloses a multi-focus composite Fresnel phase diagram rapid generation and power equalization method and system for one-to-many free space laser communication. According to the method, aiming at a scene in which a plurality of user targets are located at different directional angles and different propagation distances, a focusing + directional single-beam phase is constructed for each target on the basis of analyzing a Fresnel zone lens phase and a linear tilt phase, and the phase is taken after complex field superposition is performed according to a preset power weight, so that the target target is obtained. A composite phase diagram for a phase-type spatial light modulator (SLM) is directly obtained. The power weight is preset according to a link budget or a task demand so as to realize on-demand distribution and equalization of multi-beam output power; and meanwhile, fixed phase bias can be introduced to each beam to suppress inter-beam interference fringes. According to the method, frame-by-frame iterative solution is not needed, the calculation complexity is low, and high-frame-rate and low-delay online updating is easy to realize.

The invention discloses a cell hologram automatic focusing and aberration compensation phase reconstruction method based on deep learning, and the method comprises the steps: obtaining a to-be-processed off-axis digital hologram of a cell sample based on an off-axis digital holographic microscopy system, and carrying out the preprocessing of an original hologram, and enhancing the data size; processing the holograms in batches by using a phase reconstruction method considering aberration compensation to generate corresponding phase diagrams, and forming a ''hologram-phase diagram'' image pair data set for model training; the image pair data set is used for training a pix2pix network model, the input of the model is a cell hologram, and the output of the model is a focusing phase diagram; according to the invention, automatic focusing and phase reconstruction can be simultaneously realized for a single hologram, a clear and distortionless in-focus phase diagram is directly output, the problem that only an object in a specific distance range can be clearly imaged is solved, and the method is suitable for cell observation, label-free pathological detection and dynamic analysis of living cells in the field of biomedicine.

This invention discloses a method and system for de-flattening preprocessing, belonging to the field of radar imaging. The method includes: acquiring a main radar image and a secondary radar image, each containing several main image scattering points and several secondary image scattering points; calculating the secondary image scattering points corresponding to the main image scattering points to form several scattering point pairs; performing a flat-ground phase acquisition action to obtain an ideal flat-ground phase, thereby forming an ideal flat-ground phase map and completing the de-flattening preprocessing process. The flat-ground phase acquisition action includes: calculating the main image Doppler history and the secondary image Doppler history of the scattering point pairs; determining the main image focusing time that meets a preset time threshold to calculate the main image slant range, thereby determining the secondary image focusing time that meets the preset time threshold, and calculating the secondary image slant range based on the secondary image focusing time; and obtaining the ideal flat-ground phase of the scattering point pairs based on the main image slant range and the secondary image slant range. The de-flattening preprocessing method disclosed in this invention can effectively reduce the processing error of de-flattening preprocessing methods.

The application discloses a damage detection method based on a sparse wing array frequency modulation spectrum phase mapping method, and belongs to the technical field of crack detection. The method comprises the following steps: emitting a linear sweep wave and receiving a return wave; processing the return wave by using a spectrum phase mapping method. The main process of the spectrum phase mapping method comprises twin product transformation and Fourier transformation. The frequency difference between the sweep wave and the return wave can be obtained accurately, so that the distance from the damage to a sweep wave transceiving assembly can be calculated. The sweep wave transceiving assembly, namely a sparse wing array receiving device, is used for accurately positioning the damage. The device can firstly roughly determine the target direction, and then accurately position the damage crack according to a pair of receivers. The application can effectively improve the amplitude of the return wave signal, so that more accurate distance and position can be obtained, and the practicability is high.

The invention discloses a fatigue test crack detection method based on thermal imaging. In the periodic fatigue loading process, the surface temperature change of a sample is detected in real time through infrared thermal imaging, and an amplitude diagram and a phase diagram of weak temperature fluctuation are obtained through calculation; segmenting the sample through local phase consistency, prefabricating a gap and a background, and only performing subsequent analysis on a sample area so as to eliminate background interference; after the amplitude diagram is binarized, the boundary displacement influence is eliminated through a simple boundary displacement review strategy and by means of the boundary displacement direction and stress concentration point position relation, complex feature point matching and displacement estimation between images do not need to be conducted through the algorithm, the calculated amount is small, and reliability is high; the crack length is calculated according to the detected movement track of the crack tip feature point, the method does not depend on static crack features, the basic assumption that sample changes inevitably come from damage generation and development is utilized, and crack length evaluation is not affected even if wrong feature points are extracted through single-frame heat map analysis.

This application discloses a structured light encoding and decoding method based on polarization state modulation, relating to the field of 3D reconstruction technology. The method includes: controlling a projector to sequentially project a group of polarized structured light patterns onto the object under test, and controlling a polarization camera to synchronously acquire these patterns, obtaining a corresponding polarization image sequence; calculating the polarization angle of each camera pixel based on the polarization image sequence, obtaining a polarization angle map for each frame; for each camera pixel, calculating the wrapping phase based on the polarization angle map, obtaining a wrapping phase map for that frequency; obtaining an absolute phase map based on the wrapping phase map using a single-frequency absolute phase unfolding algorithm, establishing a mapping relationship between the column coordinates of camera pixels and projector pixels; and, based on pre-calibrated intrinsic and extrinsic parameters of the camera and projector, combined with the linear mapping relationship, calculating the 3D point cloud of the object under test through triangulation. This application aims to address the shortcomings of 3D reconstruction results being affected by the reflectivity of the object surface and ambient lighting.

Techniques for characterizing wafer bow are provided. In some embodiments, a method for determining wafer bow characteristics may involve projecting, using a projection device disposed in or on a portion of a semiconductor fabrication chamber, one or more fringe pattern images onto a surface of a wafer. The method may further involve capturing, using one or more camera devices, images representative of reflections of the one or more fringe pattern images from the surface of the wafer. The method may further involve generating an unwrapped phase map based on the captured images. The method may further involve generating a three-dimensional reconstruction of a surface of the wafer based on the unwrapped phase map using phase-measuring deflectometry.

The invention discloses a neural network enhanced wavefront sensing method and system based on a metasurface and double-helix PSF coding, and the method comprises the steps: loading a preset reference phase diagram and a to-be-measured phase diagram on unmodulated parallel light through a spatial light modulator, thereby generating a reference wavefront and a to-be-measured wavefront; mutually orthogonal double-helix phase distribution is generated by using the polarization multiplexing super-structure surface, and a reference double-helix point spread function image and a to-be-measured double-helix point spread function image are obtained; and outputting a phase distribution matrix of the wavefront to be measured by using the self-calibration dual-encoder neural network to realize synchronous reconstruction of the dual-channel wavefront. The method can realize high-resolution real-time wavefront measurement under single exposure, has high robustness and expandability, and is suitable for the fields of adaptive optics, polarization imaging, optical communication and the like.

The application discloses a kind of based on optimization's guiding filter image fusion change detection method and device, method includes: by extreme minimum scale difference operator, pixel value difference value is to the picture of same scene different phase, obtains difference map;Using the way of guiding filter, difference map is fused on global scale, to obtain the optimal difference map;Mean filter is used to phase map I1 and I2, and the base layer difference map corresponding to each difference map is obtained, and the optimized brightness saliency map F1 and F2 are obtained by pca fusion as the image of generating saliency map, according to the principle of maximum saliency to determine weight map;Weight map is regularized for double-scale difference map reconstruction, and the final difference map is obtained;In clustering segmentation stage, by introducing soft threshold function, the final difference map is further processed, to suppress existing abnormal noise.The device includes: processor and memory.

In a digital holographic wrapped phase aberration compensation method based on deep learning, a random Zernike polynomial coefficient and a corresponding wrapped phase map are generated by a computer and are respectively treated as a learning label and a network to train a neural network model. A digital holographic optical setup is built to record a hologram of a sample to be measured, the wrapped phase map is inputted into the trained neural network model after numerical reconstruction, and the Zernike polynomial coefficient is outputted to reconstruct a phase aberration distribution and to compensate complex amplitude in a spatial domain. Phase filtering and unwrapping are performed on the compensated wrapped phase map, and Zernike polynomial fitting based on background segmentation is performed on the unwrapped phase to compensate for residual aberration.

This invention discloses a phase-height mapping calibration method and apparatus in fringe projection, relating to the field of three-dimensional object contour measurement technology. The method includes: controlling a projector to project a set of phase-shifted sinusoidal fringe patterns onto a micromirror array with known height values; simultaneously triggering a camera to acquire fringe image sequences; performing phase shift calculations on the fringe image sequences to obtain a wrap-around phase map; constructing a global optimization model of absolute phase using the known height value of the micromirror array as an absolute constraint; solving for the absolute phase field corresponding to the height of the micromirror array; extracting the center coordinates, absolute phase values, and known height values ​​of each micromirror element; constructing a three-dimensional control point set; fitting the three-dimensional control point set; calculating the continuous model coefficient field; and forming a phase-height lookup table. This invention can significantly improve the real-time calculation efficiency of three-dimensional measurement, meeting the practical needs of high-precision, high-stability industrial three-dimensional shape measurement.

This invention discloses a wafer laser grooving method and system, comprising: a laser beam being adapted to a spatial light modulator via optical path adjustment; the spatial light modulator loading a rectangular phase map to form a main light spot, with a high-frequency modulation pattern superimposed on the edge; the grooving width being adjusted by rotating the main light spot angle; a 4F system filtering the spectrum and reconstructing a composite light field containing the main light spot and two auxiliary sub-light spots; single-pulse staged operation, with the spatial light modulator synchronously controlling the light spot parameters; after focusing by the objective lens, the main light spot cuts the groove, and the auxiliary sub-light spots soften the edge. This invention solves the problems of poor edge quality and low efficiency of traditional methods, improving grooving accuracy, edge quality, and efficiency, and is suitable for high-precision wafer processing.

The invention provides a spaceflight synthetic aperture radar image processing software load balancing method and system, and the method comprises the steps: dividing a plurality of sub-regions as initial tasks during the execution of parallel unwrapping processing, and distributing the initial tasks to work nodes; executing an iterative unwrapping algorithm in the working node, further determining a phase residual error of each pixel point, and extracting to obtain a plurality of residual error non-convergence areas; packaging each residual error non-convergence area into residual error sub-tasks, returning the residual error sub-tasks to the main node, and dynamically redistributing the tasks to idle nodes by the main node based on the load state of each working node; the working node performs iterative solution according to the received residual subtask, and submits a solution result back to the main node to update a global phase field; and repeatedly executing the step of determining the phase residual error and updating the global phase field until the interferometric phase diagram meets a judgment condition, and realizing convergence of all pixels. By adopting the scheme of the invention, real-time load migration based on residual dynamic evolution can be realized.

A method (100) of designing a segmented display device (1) having a plurality of elements (5) arranged in an array (3), each element (5) providing an individual output such that the plurality of elements (5) form a collective output of the device (1), wherein each element (5) is actuatable to control the individual output, the method (100) comprising: providing (102) a set (7) of images (9) representing a set of collective outputs from the device (1); generating (104) phase maps (13) of the images (9), the phase maps (13) having a phase value for each element (5) of the plurality of elements (5); and based on the phase maps (13), generating a plurality of non-overlapping groups of elements, wherein the elements (5) in each group are arranged to be actuated together as a segment (15) to cause display of any one of the set of collective output.

Systems and methods for 3D image scanners for real-time dynamic 3D surface imaging are disclosed. Embodiments of the present systems and methods describe a system and method comprising a first and / or second camera, and a projector, and a processor, the projector projects structured light with a fringe pattern onto a 3D object, the processor is configured to extract a phase map and a texture image from the image, and the processor calculates depth information from the phase map. Embodiments further describe methods and systems to determine wrapped phase from the image using a Hilbert transform, and to generate absolute phase from the wrapped phase using a combination of a quality-guided path following algorithm, a two-wavelength phase unwrapping algorithm, or a Markov Random Field method, and to generate a phase map from the absolute phase to determine depth information of the 3D object. Algorithms using conformal mapping, optimal transport mapping, and Tschupmueller mapping are used to register and track captured 3D geometry surfaces.

A non-contact motion physiological sensing method and a motion physiological sensing radar. The non-contact motion physiological sensing method is executed by a processor in a signal processing device, comprising: obtaining a digital signal; obtaining a phase map and a vibration frequency map according to the digital signal, the phase map presenting an energy distribution varying with a distance relative to the motion physiological sensing radar and a phase variation, and the vibration frequency map presenting an energy distribution varying with a distance relative to the motion physiological sensing radar and a vibration frequency variation; selecting at least one candidate position with an energy intensity exceeding an energy threshold from the vibration frequency map; selecting a target position from the candidate positions; obtaining one or more target phase data according to the target position; and inputting the one or more target phase data into a machine learning model to obtain a physiological parameter prediction result. The non-contact motion physiological sensing method and the motion physiological sensing radar can accurately sense the physiological parameter in the motion state of the subject in a non-contact manner.

An ablation calculation method and an ablation calculation system, the ablation calculation method comprising: scanning a target to be measured using a gradient echo sequence containing i different echo times, obtaining a phase map corresponding to the echo time, i being a positive integer greater than or equal to 2 (S101); selecting at least two groups of phase maps corresponding to different echo times to obtain corresponding temperature difference maps (S102); obtaining a temperature map according to the temperature difference maps (S103); calculating an ablation condition according to the temperature map (S104); and the ablation calculation system comprising an ablation calculation module capable of executing the ablation calculation method.

The application provides a three-dimensional imaging method, device and equipment of a dynamic object and a storage medium. The method comprises the following steps: projecting stripes on the dynamic object according to two preset stripe frequencies and shooting a stripe image; inputting the stripe image into a preset image feature extraction model to perform feature extraction processing, and obtaining a pixel point real distribution map and a pixel point imaginary distribution map of the dynamic object; performing phase calculation on the pixel points of the dynamic object according to the pixel point real distribution map and the pixel point imaginary distribution map, obtaining a folded phase map of the dynamic object, and performing phase unfolding processing on the folded phase map to obtain an absolute phase map of the dynamic object; performing binocular matching and depth calculation on all pixel points of the dynamic object according to the absolute phase map, obtaining three-dimensional coordinate values corresponding to each pixel point, and constructing a three-dimensional image of the dynamic object according to the three-dimensional coordinate values corresponding to each pixel point. The method has a small number of stripe images required in the implementation process and high three-dimensional imaging precision of the dynamic object.

A method of using computer-generated holography to determine a corrective lens prescription comprises computing a hologram of an image. An aberration phase map is computed using a set of Zernike pol

The present application relates to the field of structured light three-dimensional measurement technology, and particularly relates to a method for reconstructing and improving least square iterative phase unwrapping based on four-step phase shifting. An object light field is obtained on an imaging plane after a lens in a holography process; four reference light fields are generated by changing the phase of the reference light to interfere with the object light field, four-step phase shifting holograms are obtained, and an arctangent calculation is performed to obtain a wrapped phase map; a discrete Poisson equation of the wrapped phase map is established according to the least square method, and iterative solving is performed to obtain the real phase of the wrapped phase map. The unwrapping algorithm of the present application is optimized by the least square method multiple iterations, so that the partial derivative of the real phase and the difference value of the wrapped phase difference are minimized, the unwrapping error under noise is effectively reduced, and the Poisson equation is introduced for iterative solving, so that the quality of phase unwrapping is improved, and the robustness of the algorithm is improved.