11 results about "Speckle correlation" patented technology

The present application belongs to the technical field of image processing, and particularly relates to a VCSEL growth process real-time monitoring method based on image processing, which comprises the following steps: collecting an initial reference image and growth images at each time; calculating a deposition rate and a cumulative abruptness at each time; obtaining an incremental displacement field and a correlation coefficient by a digital speckle correlation method; determining a cumulative displacement field based on the incremental displacement field and an anchor point displacement field of the current round; in response to the cumulative abruptness being greater than or equal to a cumulative abruptness threshold, taking the cumulative displacement field at the time as a new anchor point displacement field and taking the growth image at the time as a new reference image; repeating iteration to obtain a cumulative displacement field in a whole growth period and calculate a cumulative stress. The present application significantly improves the accuracy of cumulative stress calculation.

The application discloses a kind of based on digital speckle's fiber winding gas cylinder defect detection method and system, high contrast speckle pattern is made on the surface of gas cylinder;Controllable load is applied to gas cylinder, and the image sequence of the surface of gas cylinder before and after load is collected;Based on the image sequence of the surface of gas cylinder, the full-field displacement field data of the surface of gas cylinder is calculated by digital speckle correlation method;The full-field displacement field data of the surface of gas cylinder is corrected by surface coordinate transformation;According to the full-field displacement field data of the surface of gas cylinder after correction, the full-field strain distribution image set of the surface of gas cylinder is calculated using difference method;The full-field strain distribution image set of the surface of gas cylinder is processed by image enhancement;Based on the full-field strain distribution image set of the surface of gas cylinder after enhancement, extract quantitative feature parameters, and utilize machine learning model to automatically identify and classify gas cylinder defect.By surface coordinate transformation correction, small microdefects can be identified, detection efficiency is improved, and detection cost is reduced.

The invention discloses a piezoelectric transducer surface micro-deformation detection method and system based on high-speed camera shooting, and belongs to the field of piezoelectric material dynamic deformation detection. According to the method, a non-contact, full-field and high-temporal-spatial-resolution detection scheme is provided for solving the problems of low frame rate of single-point measurement of a laser Doppler vibration meter and common optical measurement. According to the system, a binocular high-speed camera is adopted, a digital speckle correlation method (DIC) is combined, and accurate measurement of three-dimensional coordinates, micrometric displacement and a strain field of the transducer is achieved by synchronously collecting working images of the transducer underwater or in the air. The method comprises the key steps of binocular camera calibration, speckle marking, image preprocessing, obtaining of a sub-pixel displacement field through a DIC algorithm, and reconstruction of a three-dimensional shape and full-field strain distribution. According to the method, the surface vibration mode can be identified, three-dimensional vibration modeling and vibration-sound field data fusion are supported, the analysis capability on the resonance characteristic and the energy conversion efficiency of the transducer is effectively improved, and the method is suitable for scenes such as ocean exploration, underwater search and rescue, transducer optimization and the like.

The application discloses a kind of directional crystal mould shell automatic detection cleaning system.In the application, by transient air pressure excitation and multi-scale wavelet domain digital speckle correlation detection, the micro crack identification ability is identified from surface opening defect to sub-surface strain anomaly stage, which significantly improves the detection sensitivity of hidden cracks and wall thickness thinning defects, and replaces artificial visual experience determination with full-field strain cloud quantification grading, which significantly reduces the missed detection rate and the quality risk caused by human error. Strain-cleanness dual-factor fusion evaluation simultaneously completes the judgment of structural integrity and internal cavity cleanliness at the same station, improving the completeness and automation of defect evaluation, reducing the drag of batch offline sampling and chemical permeation operation on production rhythm, and eliminating the need for fluorescent penetrant immersion and cleaning process with transient pulse excitation method, which improves the single-piece detection rhythm and reduces the cost of hazardous chemicals procurement, storage and waste liquid treatment.

The invention belongs to the technical field of image processing, and particularly relates to a VCSEL growth process real-time monitoring method based on image processing, and the method comprises the steps: collecting an initial reference image and growth images at all moments; for each moment, calculating a deposition rate and cumulative mutability; obtaining an incremental displacement field and a correlation coefficient through a digital speckle correlation method; determining an accumulated displacement field based on the incremental displacement field and the anchor point displacement field of the current round; in response to the cumulative mutability being greater than or equal to a cumulative mutability threshold value, taking the cumulative displacement field at the moment as a new anchor point displacement field, and taking the growth image at the moment as a new reference image; iterating repeatedly to obtain an accumulated displacement field of the whole growth cycle and calculate accumulated stress. According to the method, the accuracy of accumulated stress calculation is remarkably improved.

The invention discloses a digital speckle-based fiber-wound gas cylinder defect detection method and system. The method comprises the following steps: making a high-contrast speckle pattern on the outer surface of a gas cylinder; a controllable load is applied to the gas cylinder, and a gas cylinder surface image sequence before and after the load is applied is collected; based on the gas cylinder surface image sequence, calculating through a digital speckle correlation method to obtain gas cylinder surface full-field displacement field data; curved surface coordinate transformation correction is carried out on the whole displacement field data of the gas cylinder surface; according to the corrected gas cylinder surface full-field displacement field data, a gas cylinder surface full-field strain distribution image set is obtained through calculation by adopting a difference method; performing image enhancement processing on the gas cylinder surface full-field strain distribution image set; and based on the enhanced gas cylinder surface full-field strain distribution image set, quantitative characteristic parameters are extracted, and gas cylinder defects are automatically identified and classified by using a machine learning model. Through curved surface coordinate transformation and correction, micro defects can be identified, the detection efficiency is improved, and the detection cost is reduced.

The application discloses a high-temperature material filter image collection and performance testing method for industrial vision, and particularly relates to the field of optical imaging technology; the method is characterized in that: original image data of a surface of a measured material is collected, infrared radiation stray light is filtered out, and multi-channel filter image data is obtained; center wavelength drift and bandwidth change of each channel in the multi-channel filter image data are analyzed, and channel spectrum drift data is obtained; brightness stability and edge definition of each channel image are analyzed, and image quality evaluation data is output; a correlation model is established, filter device calibration parameters are output, and filter center wavelengths and bandwidths of each filter device are adjusted in real time, so that calibrated multi-channel filter image data is obtained; a digital speckle correlation method is used to analyze deformation characteristics of the surface of the material, and high-temperature mechanical performance parameters of the material are extracted, which helps to improve the accuracy of material strain identification and mechanical performance extraction.

The application relates to a wide-band super-Rayleigh speckle correlation imaging spectrometer based on dispersion compensation, and the imaging scheme comprises and is not limited to the following imaging schemes: a front compensation scheme, a rear compensation scheme or a front-rear joint compensation scheme. The device comprises a front imaging module, a filter, a phase modulation module, a relay imaging module, a surface array detector and a computer and the like. The application utilizes the dispersion characteristics of the front imaging module or the relay imaging module to cooperate with the phase modulation module to realize super-Rayleigh speckle modulation in a wide band, and applies the super-Rayleigh speckle modulation to a correlation imaging spectrometer, so that the imaging quality of the correlation imaging spectrometer under low signal-to-noise ratio is improved.

A high-dynamic surface single-frame measurement method based on a multi-view digital speckle correlation method. The measurement method comprises: on the basis of a four-view camera and a lithographic speckle projection module, constructing a speckle projection collection system, and on the basis of the speckle projection collection system, collecting a single-frame image of a workpiece under test; on the basis of a multi-scale robust multi-view matching algorithm, processing the single-frame image of the workpiece under test, so as to obtain an intermediate depth map and pixel-wise spatial oblique planes; on the basis of a digital speckle correlation method, performing iterative calculation on intermediate parameters of the pixel-wise spatial oblique planes, so as to obtain final parameters of the spatial oblique planes; and on the basis of the final parameters of the spatial oblique planes and a left-right consistency cross-check, fusing final depth maps, so as to obtain final point cloud data. The high-dynamic surface single-frame measurement method based on a multi-view digital speckle correlation method can use a single-frame image to rapidly re-construct a workpiece having a high-dynamic surface in a field of view, so as to obtain point cloud with high integrity and high precision, and the measurement precision thereof can reach 0.03-0.07 mm.

The application provides a non-continuous deformation displacement field reconstruction method, system, electronic equipment and medium, and belongs to the field of material dynamics analysis. The method comprises the following steps: collecting a reference image and a non-continuous deformation image; arranging control points in the reference image; performing digital speckle correlation calculation according to the control points in the reference image and the non-continuous deformation image to obtain an initial displacement field; drawing a ZNCC distribution map according to the reference image, a ZNCC value and a deformation subset, and determining a non-continuous boundary track and a non-continuous deformation region; removing data in the non-continuous deformation region in the initial displacement field, and filling a blank region to obtain a predicted displacement field; determining a non-continuous control point subset according to the non-continuous boundary track, the non-continuous deformation region, the predicted displacement field and the reference image; performing digital speckle correlation calculation according to the non-continuous control point subset to update the predicted displacement field, and obtaining a non-continuous deformation displacement field. The application improves the reconstruction accuracy of the non-continuous deformation displacement field.

The present application belongs to the field of optical scattering imaging technology. When using the method based on optical memory effect to realize the imaging through scattering medium, once the size of the imaging target exceeds the range of the memory effect, it will usually lead to the failure of imaging, thereby limiting the field of view of the imaging system. The present application proposes a method of directly using correlation to expand the field of view, directly using the speckle autocorrelation of sub-target O i , the speckle cross-correlation calculation of sub-target O i and sub-target O i+1 , the relative position between sub-target image O i and O i+1 , the shift vector of the relative position between sub-target image O i and O i+1 , the correct flipping direction of sub-target image O i is determined by using the correlation between speckles, avoiding the estimation of point spread function PSF of the imaging system, thereby improving the efficiency. When the size of the target exceeds the range of the optical memory effect, the proposed method is used to more efficiently realize the non-invasive large field of view imaging through the scattering medium.