23 results about "Phase map" patented technology

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.

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.

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.

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 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.

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 phase order correction method for multi-frequency cascaded phase unwrapping is proposed. First, the low-frequency unfolded phase is directly calculated using the multi-frequency fringe method, and then the mid-frequency unfolded phase is obtained to acquire the initial fringe order obtained through a small frequency ratio. Subsequently, based on the shifting wrapped phase method, a fringe order misaligned by half a cycle from the initial fringe order is obtained. Accurate phase reconstruction is achieved through fringe order correction. These two methods complement each other to simultaneously address the accuracy degradation caused by pseudo-2-step transitions and impulse noise errors, while preserving phase map details. This invention obtains the correct order corresponding to the high-frequency wrapped phase through a phase recovery method at two fringe frequencies, and uses this to calculate the high-frequency unfolded phase, achieving fast and accurate phase unwrapping.

The present disclosure relates to a micro-nano structure manufacturing system and method, wherein the micro-nano structure manufacturing system comprises: a light source module for generating a first illumination light field; a host computer for generating a phase map that can represent a target micro-nano structure; a spatial light modulator for performing wavefront phase modulation on a light field at a corresponding position in the first illumination light field based on a phase distribution in the phase map to obtain a second illumination light field; and a projection imaging module for filtering and removing a high-frequency background light field in the generated second illumination light field by using a low-pass filtering characteristic of the projection imaging module, and retaining a target light field that is used for micro-nano structure processing. Therefore, embodiments of the present disclosure solve the dependence of a projection lithography system on a physical mask.

This invention provides a demodulation method and system for free-space optical communication links based on helical fractional orbital angular momentum. N data streams are loaded onto a Gaussian beam, and at least one modulated beam of helical fractional OAM (Optical Aspect-Oriented Motion) is generated through a spatial optical phase modulation module. After coaxial beam combining, the beam is emitted in free space and imaged onto the demodulation phase modulation module plane via an optical relay imaging system. A conjugate helical phase map is loaded to demodulate the target OAM, and the focusing optics module is adjusted to couple the peak of the target OAM beam into a single-mode fiber, while non-target OAM beams are isolated. After verifying the demodulation isolation, the demodulation phase map is switched to sequentially recover each data stream. This invention achieves hybrid multiplexing of helical fractional and integer OAM, and achieves a mode isolation of ≥5dB through a dual isolation mechanism of phase conjugate demodulation and spatial optimal focusing. This improves fiber coupling efficiency and communication link robustness, significantly expanding the channel capacity and spectral efficiency of free-space optical communication.

This application relates to radar remote sensing data processing technology, and in particular to an automatic unwrapping method for InSAR based on coherence hierarchical constraints. The method includes: acquiring an interferometric wrapped phase map and a coherence coefficient map; extracting coherence features to generate a coherence hierarchy map containing high, medium, and low-coherence regions; performing initial unwrapping based on the coherence hierarchy map and recording the propagation source, constructing a coherence hierarchy propagation map with propagation risk weights; detecting propagation anomalies using closed-loop errors, boundary cycle slip abrupt changes, and abnormal intrusions in high-coherence regions; when anomalies are detected, tracing the erroneous path back to a high-coherence confidence anchor point, performing a backtracking process, and clearing integer cycle slips on the erroneous path; re-selecting candidate integer cycle slip combinations under confidence anchor point constraints for local re-unwrapping, and updating the final unwrapped phase map and confidence marker map. This application can effectively solve the problem of misjudgment spreading from low-coherence regions to high-coherence regions, improving the stability and reliability of the unwrapping results.

This invention relates to a method and system for denoising phase-shifted shear speckle interferograms, specifically within the field of phase-shifted shear speckle interferogram denoising technology. The method includes: acquiring several phase-shifted shear speckle interferograms; calculating discrete complex phase quantities based on the several phase-shifted shear speckle interferograms, and calculating discrete wrapped phases based on the discrete complex phase quantities; calculating phase confidence weights based on the discrete complex phase quantities and discrete wrapped phases; constructing diffusion weight coefficients based on the phase confidence weights; calculating discrete phase gradients based on the discrete wrapped phases using a finite difference method, and performing weighted diffusion processing on the discrete phase gradients based on the diffusion weight coefficients; and reconstructing the phase of the phase-shifted shear speckle interferograms based on the weighted diffusion processed discrete phase gradients to obtain the denoised phase distribution. This invention can effectively denoise phase-shifted shear speckle interferograms.

This application proposes an image processing apparatus, a 3D scanning system, and an image processing method. The image processing apparatus includes: a wrapping phase control module, used to acquire several groups of phase-shifted images at different frequencies, and perform parallel wrapping phase calculations based on several phase-shifted images in each group of phase-shifted images to obtain several wrapping phase maps; each wrapping phase map includes several wrapping phase data; an unwrapping phase control module, used to perform multi-frequency heterodyne phase unwrapping parallel calculations based on each wrapping phase map to obtain absolute phase data; and an interface control module, used to acquire the absolute phase data and transmit the absolute phase data to a host computer. This application improves the 3D reconstruction frame rate.

This invention provides a method and system for optical domain crosstalk compensation of mode multiplexing signals based on neural networks. The method includes the following steps: a receiver receives OAM signal light in real time; the receiver analyzes the OAM signal light using a spatial light modulator to obtain an actual light intensity map of the OAM signal light; an initial latent vector is randomly generated based on a Gaussian distribution; the latent vector is iteratively calculated for a preset number of rounds based on the real-time actual light intensity map; in each round of iterative calculation, the latent vector is input into a preset generator to generate a turbulence phase map, which is then input into a preset feedforward network. The feedforward network outputs a predicted light intensity map; a loss function is calculated based on the predicted light intensity map and the real-time actual light intensity map; the latent vector is updated based on the loss function; after completing the preset number of iterative calculations, the complex conjugate of the final turbulence phase map is fed back to the spatial light modulator so that the spatial light modulator compensates for the OAM signal light incident at the receiver.

This invention relates to an adaptive optimization method for welding process parameters based on online detection of weld defects in ship hulls. Addressing the challenges of multi-source physical signal interference and the difficulty in real-time and accurate identification of weld defect evolution, this invention proposes a dynamic optimization method for arc voltage based on multi-sensor real-time feature extraction, phase map construction, and feedback closed-loop control. This method fuses multi-source signals such as molten pool acoustics, infrared thermals, and gas flow fields, performs denoising, normalization, and principal component analysis to form a weld feature vector, and maps it to a defect evolution phase map, achieving real-time identification and labeling of weld defect evolution. Based on the identification results, intelligent matching and switching of voltage response strategies enable precise adjustment and feedback optimization of the arc voltage. This method improves the spatiotemporal resolution of weld defect identification and the adaptability of voltage control, thereby enhancing welding quality and stability.

This invention discloses a laser processing method and system for narrow-pitch discrete tombstone array circuits, relating to the field of laser three-dimensional processing technology. The laser processing method is as follows: First, a metal thin film is deposited over the entire discrete tombstone array sample; then, the three-dimensional curved surface is discretized into several sub-regions according to the incident angle tolerance threshold and a representative incident angle is assigned; an incident angle-wavefront compensation database is constructed, generating a set of collaborative processing parameters including a spatial light modulator compensation phase map, energy compensation parameters, and dynamic focusing parameters; finally, processing is performed sequentially according to the sub-regions, adjusting the workpiece posture through a multi-axis linkage platform so that the angle between the surface normal and the optical axis equals the representative incident angle, and the etching is completed after loading the corresponding parameter set. This invention effectively corrects spot distortion and energy attenuation through regional static wavefront pre-compensation and multi-parameter collaborative control, achieving high consistency in etching linewidth, depth, and morphology across the entire curved surface, significantly improving the manufacturing accuracy and reliability of the conformal circuit.

This invention relates to the field of binocular structured light 3D measurement technology, specifically to a binocular structured light disparity map calculation method, apparatus, and readable medium. The method includes: constructing a disparity value sequence; calculating several cost maps corresponding to each disparity value to be searched based on each disparity value in the disparity value sequence, a phase map obtained from the left camera, and a phase map obtained from the right camera; constructing a minimum cost map and an optimal index map; updating the minimum cost map and the optimal index map based on the mapping relationship between the cost maps, the disparity values ​​to be searched, and the disparity value sequence; and then determining the disparity value of the minimum matching cost corresponding to each pixel position based on the updated optimal index map to generate a disparity map. By employing a whole-map operation method on the cost map, minimum cost map, optimal index map, and disparity map instead of point-by-point looping, the problem of low computational efficiency and exponential increase in computational complexity with image resolution and disparity range in existing technologies is solved.

This invention discloses an engineering visual inspection and analysis system based on the Internet of Things (IoT) and AI, comprising: an optical reading terminal for projecting sinusoidal fringe structured light of a specific frequency onto the surface of the engineering project under test, and acquiring fringe images with multi-step phase shifts using a polarization filter; an edge processing unit connected to the optical reading terminal for calculating a wrap-around phase map based on the acquired fringe images, extracting defect features and generating feature vectors, and simultaneously acquiring the physical coordinates of the surface of the engineering project under test; an IoT communication gateway for binding the physical coordinates with the feature vectors to generate structured data packets, and uploading the structured data packets; and a cloud processing server for receiving the structured data packets, establishing a digital twin of the engineering entity, and determining the defect status based on the difference between historical feature vectors and current feature vectors.

The application discloses a two-dimensional photoelectric array signal processing method for obtaining discharge positions and spectral information. In the method, optical filtering coating or covering filters are arranged in the row direction of an m*m two-dimensional photoelectric array to form m columns of spectral receiving areas. The unit outputs of each column and each row of the two-dimensional photoelectric array are led out in parallel and connected to m summation operation circuits respectively. Each summation operation circuit outputs the summation of each unit signal I(i, j) in the m columns and the summation of each unit signal I(i, j) in the m rows. A central processing unit processes the m pulse signals collected in T1 and T2 periods. The pulse full waveform is extracted, and the pulse peak value and the peak time are extracted. The spectral pulse signals and the position pulse signals are recorded in a memory. The phase map is used for statistical analysis to obtain the phase statistical map of the spectral band and the phase statistical map of the position.