Calibration method, device and equipment of linear array scanning imaging and storage medium

Abstract

The application provides a kind of linear array scanning imaging calibration method, device, equipment and storage medium, the reliability of calibration result is evaluated by introducing the solution quality evaluation index, and the linear solution or nonlinear optimization path is adaptively selected according to the evaluation result, so that the high efficiency of linear algorithm is maintained when the image quality of calibration is good, and the nonlinear optimization is automatically switched under non-ideal conditions, to ensure that the calibration solution is always stable convergence.At the same time, the linear scanning mode calibration result is fed back to the area array mode calibration process, the joint iterative optimization of area array calibration and linear scanning calibration is realized, the limitation that two calibration stages are independent in the traditional method is broken, and the natural defect of insufficient number of pixels in linear scanning direction is effectively compensated.Finally, high-precision calibration results are output when the preset convergence condition is met, which significantly improves the calibration robustness and precision of linear array scanning imaging system in nanoscale detection scene.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a calibration method, apparatus, device, and storage medium for linear array scanning imaging. Background Technology

[0002] In the field of high-precision industrial vision inspection, linear scanning imaging systems are widely used in nanometer or submicron level measurement scenarios such as semiconductor wafer defect detection, photolithography pattern alignment, and flat panel display inspection due to their extremely high spatial resolution in the scanning direction. The calibration accuracy of the linear scanning camera directly determines the overall measurement accuracy and imaging quality of the system. Existing linear scanning camera calibration methods typically employ a two-stage strategy: first, a checkerboard calibration board is photographed using an area scan mode, and the camera's intrinsic and extrinsic parameters and distortion coefficients are solved using linear least squares; then, the camera rotation angle is calibrated separately using the linear scan mode. However, as system resolution increases to the nanometer level, existing methods have revealed the following shortcomings: poor stability of linear solutions under high noise conditions; non-negligible errors in corner extraction due to factors such as calibration plate process errors, optical diffraction aberrations, and image noise; linear algorithms are prone to getting trapped in local optima or even failing to converge. Furthermore, traditional methods lack evaluation and adaptive mechanisms for solution quality, employing the same linear solution process regardless of data quality. When the calibration image is incomplete (e.g., the line scan direction cannot capture a complete checkerboard pattern) or is noisy, they cannot automatically switch to a more robust optimization strategy. In addition, area calibration and line scan calibration are isolated; the line scan mode is only used to correct rotation angles, and its calibration results cannot be fed back to optimize area calibration parameters, resulting in limited overall system calibration accuracy and difficulty in meeting high-precision requirements at the sub-pixel or even 0.1 pixel level.

[0003] In summary, the problems existing in the current technology urgently need to be solved. Summary of the Invention

[0004] This invention provides a calibration method, apparatus, device, and storage medium for linear array scanning imaging, which addresses the deficiencies in the prior art and improves the calibration robustness and accuracy of linear array scanning imaging systems in nanoscale detection scenarios.

[0005] This invention provides a calibration method for linear array scanning imaging, comprising: Acquire calibration images and scanned images of the calibration board captured by the line scan camera. The calibration images are acquired by the line scan camera in area scan mode, and the scanned images are acquired by the line scan camera in line scan mode. Based on the calibration image and calibration board feature information, the initial calibration result of the area array mode is obtained by linear solution; A solution quality evaluation index is constructed based on the initial calibration results of the area array mode. The solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode. When the solution quality evaluation index does not meet the preset conditions, the target calibration result of the array mode is obtained through nonlinear optimization; Based on the target calibration results of the area scan mode, the scanned image is calibrated to obtain the line scan mode calibration results. Based on the line scan mode calibration result, the array mode calibration process is updated with feedback, and the array mode calibration and line scan mode calibration are jointly iterated until the preset convergence condition is met, at which point the target calibration result is output. The target calibration result includes the line scan mode calibration result and the array mode target calibration result that meet the convergence condition.

[0006] According to the calibration method for linear array scanning imaging provided by the present invention, the step of obtaining the initial calibration result of the area array mode through linear solution based on the calibration image and the feature information of the calibration plate specifically includes: A linear constraint relationship is established based on the image coordinates of feature points and the corresponding spatial coordinates of feature points in the calibration image; The initial values ​​of the camera rotation and displacement parameters are determined based on the linear constraint relationship. Calculate the initial value of the liberation rate parameter based on the camera rotation and displacement parameters; The initial values ​​of the distortion parameters are calculated based on the camera rotation parameters, displacement parameters, and magnification parameters to obtain the initial calibration results of the area array mode.

[0007] According to a calibration method for linear array scanning imaging provided by the present invention, the step of constructing a solution quality evaluation index based on the initial calibration result of the area array mode, wherein the solution quality evaluation index is used to characterize the reliability of the initial calibration result of the area array mode, specifically includes: Based on the initial calibration results of the array mode, the predicted image coordinates corresponding to the calibration feature points are obtained. An error vector is constructed based on the deviation between the predicted image coordinates and the actual image coordinates; Calculate the solution quality evaluation index based on the error vector; The solution quality evaluation index is compared with a preset evaluation threshold. When the solution quality evaluation index meets the preset evaluation threshold, it is determined that the current calibration result meets the reliability requirements; When the solution quality evaluation index does not meet the preset evaluation threshold, the current calibration result is determined to not meet the reliability requirements.

[0008] According to a calibration method for linear array scanning imaging provided by the present invention, after the step of constructing a solution quality evaluation index based on the initial calibration result of the area array mode, wherein the solution quality evaluation index is used to characterize the reliability of the initial calibration result of the area array mode, the method further includes: When the solution quality evaluation index meets the preset conditions, the initial calibration result of the area array mode is used as the target calibration result of the area array mode.

[0009] According to the calibration method for linear array scanning imaging provided by the present invention, the step of obtaining the calibration result of the area array mode target through nonlinear optimization when the solution quality evaluation index does not meet the preset conditions specifically includes: An optimized model of the area array pattern is constructed based on the initial calibration results of the area array pattern, and the initial calibration results of the area array pattern are used as the initial values ​​of the optimized model of the area array pattern. The optimized model of the array mode is solved using a nonlinear optimization algorithm to obtain the updated magnification parameters; The solution quality evaluation index is recalculated based on the updated magnification parameters; When the recalculated solution quality evaluation index meets the preset conditions, the current optimization result is determined as the target calibration result of the array mode; When the recalculated solution quality evaluation index still does not meet the preset conditions, a constrained optimization model including camera attitude parameters, platform tilt parameters and displacement parameters is constructed, and a nonlinear optimization algorithm is used to solve the constrained optimization model to obtain the area array mode target calibration result.

[0010] According to the calibration method for linear array scanning imaging provided by the present invention, the step of calibrating the scanned image based on the area array mode target calibration result to obtain the linear scan mode calibration result specifically includes: Based on the distortion parameters in the target calibration results of the array mode, the scanned image is subjected to anti-distortion processing to obtain the anti-distortion scanned image; Extract the coordinate information of the calibration feature points from the scanned image after distortion correction; A line scan mode imaging model is constructed based on the image coordinate information of the calibration feature points, the spatial coordinate information of the feature points on the calibration plate, and the target calibration results of the area array mode. The initial values ​​of the rotation parameters corresponding to the scanning direction of the linear array camera are obtained by linear solution; Based on the initial values ​​of the rotation parameters, a line scan mode optimization model is constructed, and a nonlinear optimization algorithm is used to solve the line scan mode optimization model to obtain the line scan mode calibration results.

[0011] According to the calibration method for linear array scanning imaging provided by the present invention, the step of updating the array mode calibration process based on the linear scan mode calibration result, and jointly iterating the array mode calibration and the linear scan mode calibration until a preset convergence condition is met, and then outputting the target calibration result, specifically includes: The calibration parameters used in the area array mode calibration process are updated based on the line scan mode calibration results. Based on the updated calibration parameters, the area array mode calibration is re-executed to obtain the updated optimized area array mode calibration results. Based on the updated area array mode optimization calibration results, the line scan mode calibration is re-executed to obtain the updated line scan mode calibration results; The reprojection error of the area array mode is calculated based on the updated area array mode calibration results, and the reprojection error of the line scan mode is calculated based on the updated line scan mode calibration results. When at least one of the area array mode reprojection error and the line scan mode reprojection error does not meet the corresponding error threshold, the joint iteration of area array mode calibration and line scan mode calibration continues. When both the area array mode reprojection error and the line scan mode reprojection error meet the corresponding error thresholds, the target calibration result is output.

[0012] The present invention also provides a calibration device for linear array scanning imaging, comprising: The image acquisition module is used to acquire calibration images and scanned images captured by the line scan camera on the calibration board. The calibration images are acquired by the line scan camera in area scan mode, and the scanned images are acquired by the line scan camera in line scan mode. The area array calibration module is used to obtain the initial calibration result of the area array mode through linear solution based on the calibration image and the feature information of the calibration board; The result evaluation module is used to construct a solution quality evaluation index based on the initial calibration result of the area array mode. The solution quality evaluation index is used to characterize the reliability of the initial calibration result of the area array mode. The nonlinear optimization module is used to obtain the target calibration result of the array mode through nonlinear optimization when the solution quality evaluation index does not meet the preset conditions. The line scan calibration module is used to calibrate the scanned image based on the area array mode target calibration result to obtain the line scan mode calibration result. The result output module is used to update the array mode calibration process based on the line scan mode calibration result, and to perform joint iteration of array mode calibration and line scan mode calibration until the preset convergence condition is met, and then output the target calibration result. The target calibration result includes the line scan mode calibration result and the array mode target calibration result that meet the convergence condition.

[0013] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the calibration method for linear scan imaging as described above.

[0014] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the calibration method for linear scan imaging as described above.

[0015] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the calibration method for linear scan imaging as described above.

[0016] The calibration method, apparatus, device, and storage medium for linear array scanning imaging provided by this invention evaluates the reliability of the calibration results by introducing a solution quality evaluation index. Based on the evaluation results, it adaptively selects either a linear solution or a nonlinear optimization path. This maintains the efficiency of the linear algorithm when the calibration image quality is good, and automatically switches to nonlinear optimization under non-ideal conditions such as high image noise, incomplete checkerboard patterns, or system tilt, ensuring that the calibration solution always converges stably. Simultaneously, this method feeds back the linear scan mode calibration results to the area array mode calibration process, achieving joint iterative optimization of area array calibration and linear scan calibration. This overcomes the limitation of the two calibration stages being independent in traditional methods, effectively compensating for the inherent defect of insufficient pixel count in the linear scan direction. Finally, when the preset convergence conditions are met, a high-precision calibration result is output, significantly improving the calibration robustness and accuracy of the linear array scanning imaging system in nanoscale detection scenarios. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a flowchart illustrating the calibration method for linear array scanning imaging provided by the present invention; Figure 2 This is a schematic diagram of the calibration device for linear array scanning imaging provided by the present invention; Figure 3 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0020] To address the problems in existing technologies, this invention proposes a calibration method for linear array scanning imaging to improve the calibration robustness and accuracy of linear array scanning imaging systems in nanoscale detection scenarios. The calibration method for linear array scanning imaging is described below, as follows: Figure 1 As shown, including but not limited to the following steps: Step 110: Acquire calibration images and scanned images captured by the line scan camera on the calibration board. The calibration images are acquired by the line scan camera in area scan mode, and the scanned images are acquired by the line scan camera in line scan mode.

[0021] In step 110, the pre-fabricated calibration board is first placed within the field of view of the line scan camera, and multiple calibration images are acquired by controlling the line scan camera to switch to area scan mode. The calibration images are used to obtain the distribution information of the feature points of the calibration board in the image coordinate system.

[0022] After completing the area scan mode image acquisition, the line scan camera is switched to line scan mode, and scanned images are acquired through the relative motion between the camera and the calibration plate. These scanned images are used to characterize the imaging characteristics of the line scan camera in the scanning direction, providing a data basis for subsequent line scan mode calibration.

[0023] To acquire the area array image for calibration, this embodiment does not rely on the line scan camera's own area array readout mode, but instead adopts the following "stepping-acquisition-stitching" process: the calibration board is fixed on a precision motion platform and placed within the field of view of the line scan camera; the motion platform is controlled to move the calibration board relative to the line scan camera to the initial acquisition position; the line scan camera is set to operate in single-line acquisition mode with a fixed line frequency; then the motion platform is controlled to step along a preset small step distance (this step distance is determined according to the required spatial resolution, for example, 1 / 10 to 1 / 5 of the feature point size of the calibration board) perpendicular to the scanning line direction of the line scan camera (i.e., the Y direction of the area array image); after each step, the line scan camera is triggered to acquire one line of image data; the above stepping and acquisition process is repeated until the number of acquired lines can completely cover all feature points on the calibration board; finally, all the acquired single-line image data are stacked sequentially according to the stepping order to stitch together a complete two-dimensional calibration image. The calibration image is geometrically equivalent to an image taken by a traditional area array camera in the same field of view, thus providing the necessary two-dimensional image coordinate information for subsequent linear solutions.

[0024] Step 120: Based on the calibration image and calibration board feature information, obtain the initial calibration result of the area array mode through linear solution.

[0025] In step 120, the features of the calibration plate in the calibration image are identified, the image coordinate information of the feature points is obtained, and the correspondence between the image coordinates and the spatial coordinates is established by combining the spatial coordinate information of the calibration plate feature points that is known in advance.

[0026] A linear solution model is constructed based on the aforementioned correspondence. Initial calibration parameters in the area array mode are obtained by solving this linear solution model, thus forming the initial calibration result for the area array mode. This initial calibration result characterizes the imaging relationship in the current area array mode and serves as the basis for subsequent calibration quality assessment and optimization calculations.

[0027] Step 130: Construct a solution quality evaluation index based on the initial calibration results of the area array mode. The solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode.

[0028] In step 130, the initial calibration results of the area array mode are used to establish the predicted imaging results of the feature points of the calibration board, and the predicted imaging results are compared with the actual observation results to obtain evaluation information reflecting the current solution quality.

[0029] Based on the evaluation information, a solution quality evaluation index is constructed, which characterizes the degree of matching between the initial calibration results of the current array mode and the actual observation results.

[0030] The solution quality evaluation index is then compared with preset conditions to determine whether the initial calibration result of the current array mode meets the reliability requirements, and the subsequent calibration processing path is determined based on the judgment result.

[0031] The dimension of this indicator is the same as that of image coordinates, and the unit is pixels. Its value directly reflects the average deviation between the predicted image coordinates and the actual image coordinates. The smaller the ε value, the more accurate and reliable the current calibration result is; conversely, the larger the ε value, the greater the error and the lower the reliability of the current calibration result.

[0032] Step 140: When the solution quality evaluation index does not meet the preset conditions, obtain the target calibration result of the array mode through nonlinear optimization.

[0033] In step 140, when it is determined that the initial calibration result of the current array mode has a large error or does not meet the preset accuracy requirements, an array mode optimization model is constructed.

[0034] Using the initial calibration results of the area array mode as the initial values ​​for optimization, the calibration parameters are iteratively updated through nonlinear optimization, so that the optimized parameters can more accurately represent the actual imaging process.

[0035] As the optimization process continues, the difference between the predicted results and the actual observation results is continuously reduced, and finally, the area array mode target calibration results that meet the accuracy requirements are obtained.

[0036] Step 150: Based on the target calibration result of the area array mode, perform calibration processing on the scanned image to obtain the line scan mode calibration result.

[0037] In step 150, the scanned image is corrected using the area array mode target calibration results to eliminate the influence of area array mode parameter errors on the line scan mode calibration process.

[0038] After completing the scanning image calibration, the imaging relationship in the line scan mode is established based on the calibration plate feature information in the scanning image, and the calibration parameters corresponding to the line scan mode are solved.

[0039] By optimizing the calibration parameters of the line scan mode, a line scan mode calibration result that can accurately characterize the imaging characteristics of the line scan camera in the scanning direction is obtained.

[0040] Since line scan images are composed of stitched continuous rows of data, the calibration board is typically placed at a certain angle relative to the camera scan line or moves at a constant speed with the motion platform during the scanning process. Therefore, a physical corner point on the calibration board is not presented as an isolated pixel in the line scan image, but rather as a continuous trajectory line (e.g., a diagonal line segment). To accurately extract the sub-pixel level image coordinates of this corner point from the line scan image, this embodiment employs an edge intersection method based on the known geometric constraints of the calibration board. The specific steps are as follows: First, for each physical corner point with known spatial coordinates on the calibration plate, based on its position in the world coordinate system and the scanning speed and direction of the current motion platform, the approximate row coordinate range of that corner point in the line scan image is estimated. This row range corresponds to the time interval between the corner point entering and leaving the linear field of view of the linear scan camera.

[0041] Secondly, within the estimated row range, edge detection is performed row by row. For the checkerboard calibration board, each row of image data is a one-dimensional grayscale curve, with a step change in grayscale value corresponding to the boundary between black and white squares. On this one-dimensional curve, a sub-pixel edge localization algorithm (such as a gray-scale moment-based method or polynomial interpolation) is used to determine the precise location of the edge points. This location is the column coordinate of an edge point belonging to the current corner point in that row. By traversing all rows, a set of edge points belonging to the same physical corner point is obtained.

[0042] Secondly, since the calibration plate moves at a constant linear speed during scanning, and the checkerboard boundary is a straight line, the aforementioned set of edge points should be approximately collinear in the image coordinate system. The least squares method is used to fit this set of edge points into a straight line, which represents the trajectory of the physical corner point in the online scan image.

[0043] Finally, based on the known position information of the calibration board at the start and end of the scan, the intersection point of the trajectory line and a virtual reference line (such as the center line of the calibration board or the line corresponding to the theoretical imaging time of the corner point) is determined, and the coordinates of the intersection point are used as the final image coordinates of the physical corner point in the online scan image.

[0044] For the dot calibration board, the feature extraction method is similar: each row of image data intersects with the circular region to obtain a gray-level distribution of a chord. By detecting the symmetry center or peak position of the gray-level distribution, a positioning point belonging to the center of the circle is determined on that row. Then, circle fitting or line fitting is performed on the positioning points obtained from all rows to finally determine the coordinates of the center of the circle.

[0045] Using the above method, the known geometric constraints of the calibration plate (the straight boundary of the checkerboard, the equidistant distribution of the dot array, etc.) are utilized to efficiently and robustly restore the trajectory data in the line scan image to accurate feature point coordinates, providing high-precision observation data for the subsequent construction of the line scan mode imaging model and parameter solving.

[0046] Step 160: Based on the line scan mode calibration result, update the array mode calibration process, and perform joint iteration of array mode calibration and line scan mode calibration until the preset convergence condition is met, and output the target calibration result. The target calibration result includes the line scan mode calibration result and the array mode target calibration result that meet the convergence condition.

[0047] In step 160, the line scan mode calibration result is used as feedback information to be introduced into the area array mode calibration process to update the area array mode calibration parameters.

[0048] Based on the updated area mode calibration parameters, the area mode calibration is re-executed, and then the line scan mode calibration is further executed, thus forming a joint iterative mechanism between area mode calibration and line scan mode calibration.

[0049] During each iteration, the errors of the area scan mode calibration results and the line scan mode calibration results are evaluated separately. If the error still does not meet the preset convergence condition, parameter updates and joint iterations continue; when the preset convergence condition is met, the iteration stops and the final target calibration result is output.

[0050] Through the above joint iterative process, the calibration results of the area array mode and the line scan mode are optimized in a coordinated manner, thereby improving the overall calibration accuracy and stability.

[0051] As a further optional embodiment, the step of obtaining the initial calibration result of the area array mode through linear solution based on the calibration image and calibration board feature information specifically includes: A linear constraint relationship is established based on the image coordinates of feature points and the corresponding spatial coordinates of feature points in the calibration image; The initial values ​​of the camera rotation and displacement parameters are determined based on the linear constraint relationship. Calculate the initial value of the liberation rate parameter based on the camera rotation and displacement parameters; The initial values ​​of the distortion parameters are calculated based on the camera rotation parameters, displacement parameters, and magnification parameters to obtain the initial calibration results of the area array mode.

[0052] In this embodiment, the image coordinates of the calibration board feature points are first extracted from the calibration image, and the spatial coordinates of the corresponding feature points are obtained. A linear constraint relationship is established based on the image coordinates and spatial coordinates, and the initial values ​​of the camera rotation and displacement parameters are obtained by solving the linear constraint relationship.

[0053] For example, the spatial coordinates and image coordinates satisfy a projection mapping relationship: ; in, P Represents the spatial coordinates of the feature point. p Indicates the corresponding image coordinates. M This represents a mapping matrix describing the imaging relationship. s The scale factor is represented. An overdetermined system of equations is established using multiple feature points, and the initial values ​​of the camera rotation and displacement parameters are obtained by linear solution.

[0054] After obtaining the camera rotation and displacement parameters, the initial value of the magnification parameter is calculated by combining the spatial distribution of feature points on the calibration board and the corresponding image distribution. The magnification parameter is used to characterize the proportional relationship between the actual physical size and the image size.

[0055] Subsequently, the ideal imaging position is calculated based on the currently obtained camera rotation parameters, displacement parameters, and magnification parameters. This ideal imaging position is then compared with the feature point positions in the actual image to obtain the imaging deviation. A distortion model is established based on this imaging deviation, and the initial values ​​of the distortion parameters are solved.

[0056] Finally, the camera rotation parameters, displacement parameters, magnification parameters, and distortion parameters are combined to form the initial calibration results of the area array mode, providing an initial parameter basis for subsequent solution quality evaluation and area array mode optimization.

[0057] As a further optional embodiment, the step of constructing a solution quality evaluation index based on the initial calibration results of the area array mode, wherein the solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode, specifically includes: Based on the initial calibration results of the array mode, the predicted image coordinates corresponding to the calibration feature points are obtained. An error vector is constructed based on the deviation between the predicted image coordinates and the actual image coordinates; Calculate the solution quality evaluation index based on the error vector; The solution quality evaluation index is compared with a preset evaluation threshold. When the solution quality evaluation index meets the preset evaluation threshold, it is determined that the current calibration result meets the reliability requirements; When the solution quality evaluation index does not meet the preset evaluation threshold, the current calibration result is determined to not meet the reliability requirements.

[0058] In this embodiment, after obtaining the initial calibration result of the area array mode, the feature points of the calibration board are projected using the calibration parameters in the initial calibration result to obtain the predicted image coordinates corresponding to each calibration feature point. The predicted image coordinates represent the imaging position theoretically calculated under the current calibration parameter conditions.

[0059] Subsequently, the predicted image coordinates are compared with the actual detected feature point image coordinates in the calibration image to obtain the positional deviation corresponding to each calibration feature point. Because the actual imaging process may be affected by factors such as image noise, lens distortion, platform tilt error, and parameter estimation error, there is usually a certain deviation between the predicted image coordinates and the actual image coordinates.

[0060] Furthermore, the positional deviations of multiple calibration feature points are statistically analyzed and combined to construct an error vector. This error vector reflects the overall deviation between the initial calibration result of the current area array mode and the actual observation result. The smaller the error vector, the closer the current calibration parameters are to the true imaging model; the larger the error vector, the more likely there is a large error in the calibration parameters obtained by the current linear solution.

[0061] After obtaining the error vector, a solution quality evaluation index is calculated based on the error vector. This index is used to quantitatively evaluate the reliability and accuracy of the initial calibration results of the current array mode. Specifically, the index comprehensively reflects the positional deviations of each calibration feature point, thereby avoiding evaluation bias caused by relying solely on the error of a single feature point and improving the stability and reliability of the evaluation results.

[0062] Subsequently, the solution quality evaluation index is compared with a preset evaluation threshold. When the solution quality evaluation index meets the preset evaluation threshold, it indicates that the initial calibration result of the area array mode obtained by the current linear solution can accurately describe the actual imaging process. Therefore, the current calibration result is determined to meet the reliability requirements and is used as the basic parameter for subsequent processing.

[0063] When the solution quality evaluation index does not meet the preset evaluation threshold, it indicates that there is still a significant difference between the calibration parameters obtained by the current linear solution and the actual imaging model. In this case, the current calibration result is determined to not meet the reliability requirements. Further, a subsequent nonlinear optimization process is triggered to optimize and correct the current calibration parameters, thereby improving the accuracy and robustness of the calibration result.

[0064] By setting the solution quality evaluation index, this embodiment can automatically evaluate the quality of the calibration results after completing the linear solution, and select whether to enter the subsequent optimization process based on the evaluation results, thereby avoiding low-quality initial solutions from directly participating in subsequent calculations, and improving the convergence, stability and final calibration accuracy of the entire calibration process.

[0065] For example, solving quality evaluation indicators Specifically: ; When camera tilt is ignored, r 1 、r 2 Specifically: ; When camera tilt is taken into account r 1 、r 2 Specifically: ; in, H 11 、H 12 、H 21 、H 22 、H 31 、H 32 All parameters are shared by the rotating parts; the magnification is ( ). f x , f y The principal point coordinates are ( c x , c y The principal point coordinates are iterated starting from (0, 0).

[0066] As a further optional embodiment, after the step of constructing a solution quality evaluation index based on the initial calibration results of the area array mode, wherein the solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode, the method further includes: When the solution quality evaluation index meets the preset conditions, the initial calibration result of the area array mode is used as the target calibration result of the area array mode.

[0067] In this embodiment, after the reliability assessment of the initial calibration results of the area array mode is completed, the solution quality evaluation index is compared with preset conditions. The preset conditions are used to characterize the accuracy and reliability requirements that the current calibration results need to achieve.

[0068] When the solution quality evaluation index meets the preset conditions, it indicates that the initial calibration result of the area array mode obtained based on the linear solution has a high consistency with the actual imaging situation, and the current calibration parameters can accurately describe the imaging relationship of the line array camera in the area array mode.

[0069] At this point, there is no need to continue the subsequent nonlinear optimization process. The initial calibration result of the area array mode is directly determined as the target calibration result of the area array mode, and the target calibration result of the area array mode is used as the input parameter for the subsequent line scan mode calibration process.

[0070] Furthermore, when the calibration image quality is high, the feature point extraction error is small, or the initial solution result is close to the true parameters, the solution quality evaluation index can usually meet the preset conditions. In this case, continuing to perform nonlinear optimization may not significantly improve the calibration accuracy, but will instead increase the computational load and processing time.

[0071] Therefore, this embodiment sets up a judgment mechanism based on solution quality evaluation index, which allows the initial calibration result of the area array mode to be directly used as the target calibration result of the area array mode, while ensuring that the calibration accuracy meets the requirements. This reduces unnecessary optimization calculations, improves calibration efficiency, and reduces the uncertainty caused by local convergence problems in the optimization process.

[0072] Through the above method, this embodiment realizes the adaptive selection between linear solution path and optimized solution path, enabling the calibration process to automatically match the corresponding solution strategy according to the current data quality, thereby improving the overall computational efficiency and stability while ensuring calibration accuracy.

[0073] As a further optional embodiment, the step of obtaining the array mode target calibration result through nonlinear optimization when the solution quality evaluation index does not meet the preset conditions specifically includes: An optimized model of the area array pattern is constructed based on the initial calibration results of the area array pattern, and the initial calibration results of the area array pattern are used as the initial values ​​of the optimized model of the area array pattern. The optimized model of the array mode is solved using a nonlinear optimization algorithm to obtain the updated magnification parameters; The solution quality evaluation index is recalculated based on the updated magnification parameters; When the recalculated solution quality evaluation index meets the preset conditions, the current optimization result is determined as the target calibration result of the array mode; When the recalculated solution quality evaluation index still does not meet the preset conditions, a constrained optimization model including camera attitude parameters, platform tilt parameters and displacement parameters is constructed, and a nonlinear optimization algorithm is used to solve the constrained optimization model to obtain the area array mode target calibration result.

[0074] In this embodiment, when the solution quality evaluation index obtained in step 130 does not meet the preset conditions, it indicates that there is still a large deviation between the initial calibration result of the area array mode obtained by linear solution and the actual imaging model. At this time, the nonlinear optimization process is started to further correct the calibration parameters.

[0075] First, an optimization model for the area array mode is constructed using the initial calibration results as the initial values. Since the magnification parameter has a direct impact on the imaging scale, it is prioritized as the optimization target. While keeping other calibration parameters relatively stable, the magnification parameter is iteratively updated using a nonlinear optimization algorithm, so that the theoretical projection results gradually approach the actual observation results.

[0076] After obtaining the updated magnification parameters, the projection calculation of the calibrated feature points is re-executed, and the error vector and corresponding solution quality evaluation index are reconstructed based on the new projection results. By re-evaluating the solution quality evaluation index, it can be determined whether the current optimization result has met the preset accuracy requirements.

[0077] When the recalculated solution quality evaluation index meets the preset conditions, it means that the current optimized parameters can accurately describe the actual imaging relationship. At this time, the current optimization result is determined as the area array mode target calibration result, and the subsequent line scan mode calibration process begins.

[0078] When the recalculated solution quality evaluation index still does not meet the preset conditions, it indicates that optimizing only the magnification parameter is not enough to fully eliminate the calibration error. At this time, a constraint optimization model is further constructed to jointly optimize more parameters that affect imaging accuracy.

[0079] Specifically, the constrained optimization model includes variables such as camera attitude parameters, platform tilt parameters, and displacement parameters. By introducing parameter constraints and actual imaging constraints, an optimization model that more closely resembles the real imaging process is established. Based on this, a nonlinear optimization algorithm is used to iteratively solve the constrained optimization model, enabling coordinated adjustment of multiple parameters to reduce the difference between theoretical imaging results and actual observation results.

[0080] As the optimization iterations proceed, the parameters gradually converge to a stable state, the calibration error continues to decrease, and finally the calibration result of the area array mode target that meets the accuracy requirements is obtained.

[0081] By setting up a hierarchical optimization mechanism that combines amplification parameter optimization and constraint optimization, this embodiment can adaptively select the optimization strategy based on the error of the current calibration result. For cases with small errors, only the amplification parameter needs to be optimized to obtain a high-precision calibration result; for cases with large errors, multi-parameter joint optimization is further performed to improve the convergence, stability, and final calibration accuracy of the calibration process.

[0082] As a further optional embodiment, the step of calibrating the scanned image based on the area scan mode target calibration result to obtain the line scan mode calibration result specifically includes: Based on the distortion parameters in the target calibration results of the array mode, the scanned image is subjected to anti-distortion processing to obtain the anti-distortion scanned image; Extract the coordinate information of the calibration feature points from the scanned image after distortion correction; A line scan mode imaging model is constructed based on the image coordinate information of the calibration feature points, the spatial coordinate information of the feature points on the calibration plate, and the target calibration results of the area array mode. The initial values ​​of the rotation parameters corresponding to the scanning direction of the linear array camera are obtained by linear solution; Based on the initial values ​​of the rotation parameters, a line scan mode optimization model is constructed, and a nonlinear optimization algorithm is used to solve the line scan mode optimization model to obtain the line scan mode calibration results.

[0083] In this embodiment, after obtaining the area scan mode target calibration result, the scanned image is first subjected to anti-distortion processing using the distortion parameters in the area scan mode target calibration result. Since the scanned image of a line scan camera is also affected by lens distortion and optical system errors, directly using the original scanned image for calibration can easily introduce distortion errors into the subsequent parameter solving process. Therefore, anti-distortion processing eliminates the influence of distortion factors on image coordinates, improving the accuracy of subsequent line scan mode calibration.

[0084] After completing the distortion correction process, the image coordinate information corresponding to the feature points of the calibration board is extracted from the distorted scan image, and the correspondence between the image space and the physical space is established by combining the known spatial coordinate information of the feature points of the calibration board.

[0085] Furthermore, combining the imaging parameters already obtained from the area scan mode target calibration results, a line scan mode imaging model is constructed. This line scan mode imaging model describes the mapping relationship between the spatial positions of feature points on the calibration board and the image positions during the scanning process of the line scan camera, thus providing a foundation for subsequent line scan mode parameter solving.

[0086] After establishing the linear scan imaging model, the initial values ​​of the rotation parameters corresponding to the scanning direction of the linear scan camera are first obtained using a linear solution method. Since linear solutions are characterized by high computational speed and high stability, they can provide relatively reasonable initial parameters for subsequent optimization processes.

[0087] However, due to factors such as installation errors, motion errors, and imaging noise that may exist during actual scanning, the parameters obtained by linear solutions alone cannot fully reflect the true imaging state. Therefore, after obtaining the initial values ​​of the rotation parameters, an optimization model for the line scan mode is constructed using these initial values ​​as the starting point for optimization, and a nonlinear optimization algorithm is used to iteratively optimize the relevant parameters.

[0088] During the optimization process, the theoretical imaging positions of the calibrated feature points are continuously calculated based on the line scan mode imaging model and compared with the actual observation positions. The parameters are updated by continuously reducing the deviation between the two. When the optimization process meets the preset termination condition, the corresponding parameter results are output as the line scan mode calibration results.

[0089] For example, the rotation parameter is specifically the rotation angle of the chessboard grid in the world coordinate system. : ; in, The calibration parameters are the sum of the camera and checkerboard rotation angles. This is the camera rotation angle.

[0090] Through the above methods, this embodiment fully utilizes the distortion and imaging information provided by the area array mode target calibration results, providing a reliable parameter basis for line scan mode calibration. Simultaneously, by combining linear solutions with nonlinear optimization, the convergence speed and accuracy of the line scan mode parameter solution are improved, thereby obtaining more accurate and stable line scan mode calibration results.

[0091] As a further optional embodiment, the step of updating the array mode calibration process based on the line scan mode calibration result, and jointly iterating the array mode calibration and line scan mode calibration until a preset convergence condition is met, and then outputting the target calibration result, specifically includes: The calibration parameters used in the area array mode calibration process are updated based on the line scan mode calibration results. Based on the updated calibration parameters, the area array mode calibration is re-executed to obtain the updated optimized area array mode calibration results. Based on the updated area array mode optimization calibration results, the line scan mode calibration is re-executed to obtain the updated line scan mode calibration results; The reprojection error of the area array mode is calculated based on the updated area array mode calibration results, and the reprojection error of the line scan mode is calculated based on the updated line scan mode calibration results. When at least one of the area array mode reprojection error and the line scan mode reprojection error does not meet the corresponding error threshold, the joint iteration of area array mode calibration and line scan mode calibration continues. When both the area array mode reprojection error and the line scan mode reprojection error meet the corresponding error thresholds, the target calibration result is output.

[0092] In this embodiment, after obtaining the line scan mode calibration result, it is not directly output as the final calibration result. Instead, the line scan mode calibration result is used as feedback information and introduced into the area scan mode calibration process. Since both the area scan mode calibration and the line scan mode calibration originate from the imaging process of the same line scan camera, there is a parameter correlation between the two. Therefore, the line scan mode calibration result can provide further error correction basis for the area scan mode calibration.

[0093] Specifically, the calibration parameters used in the area scan mode calibration process are updated based on the line scan mode calibration results, making the area scan mode calibration parameters closer to the actual imaging state of the line scan camera. Subsequently, the area scan mode calibration process is re-executed using the updated calibration parameters to obtain updated optimized area scan mode calibration results. Compared with the initial area scan mode calibration results, the updated optimized area scan mode calibration results can more accurately reflect the actual imaging characteristics of the camera.

[0094] Furthermore, the line scan mode calibration process is re-executed based on the updated area scan mode optimization calibration results. Since line scan mode calibration relies on the imaging parameters provided by the area scan mode calibration results, the updated area scan mode optimization calibration results can provide a more accurate parameter basis for line scan mode calibration, thereby obtaining updated line scan mode calibration results.

[0095] After completing the above updates, error assessments were performed on the calibration results of both the array mode and the line scan mode. Specifically, the array mode reprojection error was calculated by comparing the difference between the theoretical projection positions and the actual observation positions of the calibrated feature points in the array mode; the line scan mode reprojection error was calculated by comparing the difference between the theoretical projection positions and the actual observation positions of the calibrated feature points in the line scan mode.

[0096] Subsequently, the reprojection error of the area array mode and the reprojection error of the line scan mode are compared with their corresponding error thresholds. When at least one of the reprojection errors of the area array mode and the line scan mode fails to meet its corresponding error threshold, it indicates that there is still room for further optimization of the current calibration result. Therefore, the joint iterative process between the area array mode calibration and the line scan mode calibration is continued.

[0097] As the number of iterations increases, the calibration results of the area scan mode and the line scan mode mutually correct and constrain each other, and the calibration parameters gradually stabilize. The reprojection errors of both the area scan mode and the line scan mode continuously decrease. When both the reprojection errors of the area scan mode and the line scan mode meet their corresponding error thresholds, it indicates that the current calibration result has reached the preset accuracy requirement. At this point, the joint iteration process is terminated, and the target calibration result is output.

[0098] Through the aforementioned joint iteration mechanism, this embodiment breaks through the traditional independent processing method of area scan calibration and line scan calibration, realizing information sharing and collaborative optimization between area scan mode calibration results and line scan mode calibration results. Compared with performing area scan calibration or line scan calibration separately, it can effectively improve the consistency and accuracy of calibration parameters, reduce the impact of cumulative errors on calibration results, and thus improve the overall calibration accuracy and stability of the line scan camera.

[0099] For example, the objective function is specifically: ; in,[ x L ,y L ] represents the world coordinates in line scan mode. u L ，v L [Image coordinate observation in line scan mode] D L For line scan distortion model, P L For the line scan projection process, ρ L This is a set of parameters to be optimized.

[0100] The calibration device for linear array scanning imaging provided by the present invention will be described below, such as... Figure 2 As shown, the calibration device for linear array scanning imaging described below and the calibration method for linear array scanning imaging described above can be referred to in correspondence.

[0101] A calibration device for linear array scanning imaging, comprising: Image acquisition module 210 is used to acquire calibration images and scan images captured by a line scan camera on a calibration board. The calibration images are acquired by the line scan camera in area scan mode, and the scan images are acquired by the line scan camera in line scan mode. The area array calibration module 220 is used to obtain the initial calibration result of the area array mode through linear solution based on the calibration image and the feature information of the calibration board; The result evaluation module 230 is used to construct a solution quality evaluation index based on the initial calibration result of the area array mode. The solution quality evaluation index is used to characterize the reliability of the initial calibration result of the area array mode. The nonlinear optimization module 240 is used to obtain the target calibration result of the array mode through nonlinear optimization when the solution quality evaluation index does not meet the preset conditions. The line scan calibration module 250 is used to perform calibration processing on the scanned image based on the area array mode target calibration result to obtain the line scan mode calibration result. The result output module 260 is used to update the array mode calibration process based on the line scan mode calibration result, and to perform joint iteration of array mode calibration and line scan mode calibration until the preset convergence condition is met, and then output the target calibration result. The target calibration result includes the line scan mode calibration result and the array mode target calibration result that meet the convergence condition.

[0102] Figure 3 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 3 As shown, the electronic device may include: a processor 310, a communications interface 320, a memory 330, and a communication bus 340, wherein the processor 310, the communications interface 320, and the memory 330 communicate with each other via the communication bus 340. The processor 310 can call logical instructions in the memory 330 to execute a calibration method for linear array scanning imaging, the method including: Acquire calibration images and scanned images of the calibration board captured by the line scan camera. The calibration images are acquired by the line scan camera in area scan mode, and the scanned images are acquired by the line scan camera in line scan mode. Based on the calibration image and calibration board feature information, the initial calibration result of the area array mode is obtained by linear solution; A solution quality evaluation index is constructed based on the initial calibration results of the area array mode. The solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode. When the solution quality evaluation index does not meet the preset conditions, the target calibration result of the array mode is obtained through nonlinear optimization; Based on the target calibration results of the area scan mode, the scanned image is calibrated to obtain the line scan mode calibration results. Based on the line scan mode calibration result, the array mode calibration process is updated with feedback, and the array mode calibration and line scan mode calibration are jointly iterated until the preset convergence condition is met, at which point the target calibration result is output. The target calibration result includes the line scan mode calibration result and the array mode target calibration result that meet the convergence condition.

[0103] Furthermore, the logical instructions in the aforementioned memory 330 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0104] On the other hand, the present invention also provides a computer program product, the computer program product comprising a computer program that can be stored on a non-transitory computer-readable storage medium, wherein when the computer program is executed by a processor, the computer is able to execute the calibration method for linear scan imaging provided by the above methods, the method comprising: Acquire calibration images and scanned images of the calibration board captured by the line scan camera. The calibration images are acquired by the line scan camera in area scan mode, and the scanned images are acquired by the line scan camera in line scan mode. Based on the calibration image and calibration board feature information, the initial calibration result of the area array mode is obtained by linear solution; A solution quality evaluation index is constructed based on the initial calibration results of the area array mode. The solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode. When the solution quality evaluation index does not meet the preset conditions, the target calibration result of the array mode is obtained through nonlinear optimization; Based on the target calibration results of the area scan mode, the scanned image is calibrated to obtain the line scan mode calibration results. Based on the line scan mode calibration result, the array mode calibration process is updated with feedback, and the array mode calibration and line scan mode calibration are jointly iterated until the preset convergence condition is met, at which point the target calibration result is output. The target calibration result includes the line scan mode calibration result and the array mode target calibration result that meet the convergence condition.

[0105] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a calibration method for linear scan imaging provided by the methods described above, the method comprising: Acquire calibration images and scanned images of the calibration board captured by the line scan camera. The calibration images are acquired by the line scan camera in area scan mode, and the scanned images are acquired by the line scan camera in line scan mode. Based on the calibration image and calibration board feature information, the initial calibration result of the area array mode is obtained by linear solution; A solution quality evaluation index is constructed based on the initial calibration results of the area array mode. The solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode. When the solution quality evaluation index does not meet the preset conditions, the target calibration result of the array mode is obtained through nonlinear optimization; Based on the target calibration results of the area scan mode, the scanned image is calibrated to obtain the line scan mode calibration results. Based on the line scan mode calibration result, the array mode calibration process is updated with feedback, and the array mode calibration and line scan mode calibration are jointly iterated until the preset convergence condition is met, at which point the target calibration result is output. The target calibration result includes the line scan mode calibration result and the array mode target calibration result that meet the convergence condition.

[0106] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0107] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A calibration method for linear array scanning imaging, characterized in that, include: Acquire calibration images and scanned images of the calibration board captured by the line scan camera. The calibration images are acquired by the line scan camera in area scan mode, and the scanned images are acquired by the line scan camera in line scan mode. Based on the calibration image and calibration board feature information, the initial calibration result of the area array mode is obtained by linear solution; A solution quality evaluation index is constructed based on the initial calibration results of the area array mode. The solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode. When the solution quality evaluation index does not meet the preset conditions, the target calibration result of the array mode is obtained through nonlinear optimization; Based on the target calibration results of the area scan mode, the scanned image is calibrated to obtain the line scan mode calibration results. Based on the line scan mode calibration result, the array mode calibration process is updated with feedback, and the array mode calibration and line scan mode calibration are jointly iterated until the preset convergence condition is met, at which point the target calibration result is output. The target calibration result includes the line scan mode calibration result and the array mode target calibration result that meet the convergence condition.

2. The calibration method for linear array scanning imaging according to claim 1, characterized in that, The step of obtaining the initial calibration result of the area array mode through linear solution based on the calibration image and calibration board feature information specifically includes: A linear constraint relationship is established based on the image coordinates of feature points and the corresponding spatial coordinates of feature points in the calibration image; The initial values ​​of the camera rotation and displacement parameters are determined based on the linear constraint relationship. Calculate the initial value of the liberation rate parameter based on the camera rotation and displacement parameters; The initial values ​​of the distortion parameters are calculated based on the camera rotation parameters, displacement parameters, and magnification parameters to obtain the initial calibration results of the area array mode.

3. The calibration method for linear array scanning imaging according to claim 1, characterized in that, The step of constructing a solution quality evaluation index based on the initial calibration results of the area array mode, wherein the solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode, specifically includes: Based on the initial calibration results of the array mode, the predicted image coordinates corresponding to the calibration feature points are obtained. An error vector is constructed based on the deviation between the predicted image coordinates and the actual image coordinates; Calculate the solution quality evaluation index based on the error vector; The solution quality evaluation index is compared with a preset evaluation threshold. When the solution quality evaluation index meets the preset evaluation threshold, it is determined that the current calibration result meets the reliability requirements; When the solution quality evaluation index does not meet the preset evaluation threshold, the current calibration result is determined to not meet the reliability requirements.

4. The calibration method for linear array scanning imaging according to claim 1, characterized in that, After the step of constructing a solution quality evaluation index based on the initial calibration results of the area array mode, wherein the solution quality evaluation index is used to characterize the reliability of the initial calibration results of the area array mode, the method further includes: When the solution quality evaluation index meets the preset conditions, the initial calibration result of the area array mode is used as the target calibration result of the area array mode.

5. The calibration method for linear array scanning imaging according to claim 1, characterized in that, The step of obtaining the array mode target calibration result through nonlinear optimization when the solution quality evaluation index does not meet the preset conditions specifically includes: An optimized model of the area array pattern is constructed based on the initial calibration results of the area array pattern, and the initial calibration results of the area array pattern are used as the initial values ​​of the optimized model of the area array pattern. The optimized model of the array mode is solved using a nonlinear optimization algorithm to obtain the updated magnification parameters; The solution quality evaluation index is recalculated based on the updated magnification parameters; When the recalculated solution quality evaluation index meets the preset conditions, the current optimization result is determined as the target calibration result of the array mode; When the recalculated solution quality evaluation index still does not meet the preset conditions, a constrained optimization model including camera attitude parameters, platform tilt parameters and displacement parameters is constructed, and a nonlinear optimization algorithm is used to solve the constrained optimization model to obtain the area array mode target calibration result.

6. The calibration method for linear array scanning imaging according to claim 1, characterized in that, The step of calibrating the scanned image based on the area array mode target calibration result to obtain the line scan mode calibration result specifically includes: Based on the distortion parameters in the target calibration results of the array mode, the scanned image is subjected to anti-distortion processing to obtain the anti-distortion scanned image; Extract the coordinate information of the calibration feature points from the scanned image after distortion correction; A line scan mode imaging model is constructed based on the image coordinate information of the calibration feature points, the spatial coordinate information of the feature points on the calibration plate, and the target calibration results of the area array mode. The initial values ​​of the rotation parameters corresponding to the scanning direction of the linear array camera are obtained by linear solution; Based on the initial values ​​of the rotation parameters, a line scan mode optimization model is constructed, and a nonlinear optimization algorithm is used to solve the line scan mode optimization model to obtain the line scan mode calibration results.

7. The calibration method for linear array scanning imaging according to claim 1, characterized in that, The step of updating the array mode calibration process based on the line scan mode calibration result, and jointly iterating the array mode calibration and line scan mode calibration until the preset convergence condition is met, and then outputting the target calibration result, specifically includes: The calibration parameters used in the area array mode calibration process are updated based on the line scan mode calibration results. Based on the updated calibration parameters, the area array mode calibration is re-executed to obtain the updated optimized area array mode calibration results. Based on the updated area array mode optimization calibration results, the line scan mode calibration is re-executed to obtain the updated line scan mode calibration results; The reprojection error of the area array mode is calculated based on the updated area array mode calibration results, and the reprojection error of the line scan mode is calculated based on the updated line scan mode calibration results. When at least one of the area array mode reprojection error and the line scan mode reprojection error does not meet the corresponding error threshold, the joint iteration of area array mode calibration and line scan mode calibration continues. When both the area array mode reprojection error and the line scan mode reprojection error meet the corresponding error thresholds, the target calibration result is output.

8. A calibration device for linear array scanning imaging, characterized in that, include: The image acquisition module is used to acquire calibration images and scanned images captured by the line scan camera on the calibration board. The calibration images are acquired by the line scan camera in area scan mode, and the scanned images are acquired by the line scan camera in line scan mode. The area array calibration module is used to obtain the initial calibration result of the area array mode through linear solution based on the calibration image and the feature information of the calibration board; The result evaluation module is used to construct a solution quality evaluation index based on the initial calibration result of the area array mode. The solution quality evaluation index is used to characterize the reliability of the initial calibration result of the area array mode. The nonlinear optimization module is used to obtain the target calibration result of the array mode through nonlinear optimization when the solution quality evaluation index does not meet the preset conditions. The line scan calibration module is used to calibrate the scanned image based on the area array mode target calibration result to obtain the line scan mode calibration result. The result output module is used to update the array mode calibration process based on the line scan mode calibration result, and to perform joint iteration of array mode calibration and line scan mode calibration until the preset convergence condition is met, and then output the target calibration result. The target calibration result includes the line scan mode calibration result and the array mode target calibration result that meet the convergence condition.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the calibration method for linear scan imaging as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the calibration method for linear scan imaging as described in any one of claims 1 to 7.

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