Method and device for calculating remapping parameters based on calibration board

Abstract

The invention discloses a remapping parameter calculation method and device based on a calibration board, and the method comprises the steps: obtaining a calibration board image of the calibration board collected in a preset scanning mode under a set condition, and the set condition is that the calibration board is disposed on a motion platform, and the center of the calibration board is aligned with the rotation center of the motion platform; image coordinates of all mark patterns on the calibration plate are extracted according to the calibration plate image through the image processing technology, and the image coordinates of all the mark patterns comprise image coordinates of data marks and image coordinates of registration marks; and calculating calibration plate coordinates of all the data marks according to the coordinates of the registration marks in the calibration plate, performing data fitting based on the image coordinates of all the mark patterns and the calibration plate coordinates, and determining remapping parameters. According to the method and the device, the problem of low accuracy during remapping parameter determination in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of chip manufacturing, and in particular to a method and device for calculating remapping parameters based on a calibration plate. Background Art

[0002] When capturing images of some chip products, a combination of spiral scanning and concentric circle scanning is required. However, the images captured by these two scanning methods are all in polar coordinates. To facilitate user browsing, they need to be converted to Cartesian coordinates. This image and coordinate conversion process between different coordinate systems is called remapping.

[0003] Currently, most calibration methods rely on manual operation, which makes the entire calibration process not only time-consuming but also easily affected by human operation errors, resulting in low accuracy. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a method and device for calculating remapping parameters based on a calibration plate, aiming to solve the problem of low accuracy in calculating remapping parameters in the prior art.

[0005] The embodiment of the present invention is implemented as follows: A method for calculating remapping parameters based on a calibration plate, wherein the calibration plate is a wafer divided into a plurality of regions, each region being composed of respective grains with a marking pattern, wherein the marking pattern includes a data mark and a registration mark, the method comprising: Acquire an image of the calibration plate collected in a preset scanning mode under set conditions, wherein the set conditions are that the calibration plate is placed on a motion platform, and the center of the calibration plate is aligned with the rotation center of the motion platform; Extracting the image coordinates of all the marking patterns on the calibration plate according to the calibration plate image by using image processing technology, wherein the image coordinates of all the marking patterns include the image coordinates of the data marks and the registration marks; The calibration plate coordinates of all data markers are calculated according to the coordinates of the registration markers in the calibration plate, and data fitting is performed based on the image coordinates of all marker patterns and the calibration plate coordinates to determine the remapping parameters.

[0006] Furthermore, in the above-mentioned method for calculating the remapping parameters based on the calibration plate, the step of extracting the image coordinates of all the marking patterns on the calibration plate according to the calibration plate image using image processing technology comprises: The calibration plate image is thresholded based on the pixel gray value to extract the pattern area, and the black square area that constitutes each mark is filtered according to the area, shape and other information; Take two adjacent black square areas as a pair, extract the contour of each black square area respectively, calculate the Euclidean distance to get a pair of points with the closest distance between the two contours, and use the midpoint of the point pair as the candidate coordinate; The saddle point positioning algorithm is used to improve the sub-pixel accuracy of the candidate coordinates to obtain the image coordinates of the corresponding marking pattern.

[0007] Furthermore, in the above-mentioned method for calculating the remapping parameters based on the calibration plate, the step of calculating the calibration plate coordinates of all data marks according to the coordinates of the registration marks in the calibration plate comprises: The calibration plate image is thresholded based on the pixel gray value to extract the pattern area, and the black and white circular areas are filtered according to the area, shape and other information; Determine the type of registration mark according to the number and position distribution of the circular areas, and determine the X-axis and Y-axis positions and directions corresponding to the calibration plate according to the type of registration mark; The image coordinates of all data markers are converted into motion platform coordinates, a coordinate system is established according to the X-axis and Y-axis, and the coordinates of each data marker in the coordinate system are calculated, namely, the calibration plate coordinates.

[0008] Furthermore, in the above-mentioned calculation method of the remapping parameters based on the calibration plate, when the preset scanning mode is spiral scanning, the function of converting the image coordinates of all data marks into the motion platform coordinates is defined as: ; in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, and are the spiral coefficients, is the initial angle of the spiral scan, and are the camera X-axis and scanning direction resolutions, is the spiral arc length, and Mark The polar coordinates of the motion platform, and Mark The X and Y coordinates of the motion platform.

[0009] Furthermore, in the above-mentioned calculation method of the remapping parameters based on the calibration plate, when the preset scanning mode is concentric circle scanning, the function of converting the image coordinates of all data marks into the motion platform coordinates is defined as:

[0010] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, is the initial angle of concentric circle scanning, and are the camera X-axis and scanning direction resolutions, is the circle radius, and are the polar coordinates of the motion platform marked respectively, and are the X and Y coordinates of the marked motion platform, and are the X and Y coordinates of the center of the circle respectively.

[0011] Furthermore, in the above-mentioned method for calculating the remapping parameters based on the calibration plate, when the preset scanning mode is spiral scanning, the step of performing data fitting based on the image coordinates of all marking patterns and the calibration plate coordinates to determine the remapping parameters includes: Function to convert calibration plate coordinates into image coordinates definition:

[0012] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, and are the spiral coefficients, is the initial angle of the spiral scan, and are the camera X-axis and scanning direction resolutions, and are the polar coordinates of the motion platform marked respectively, and are the X and Y coordinates of the marked motion platform, and are the image X and Y coordinates of the marker, is the affine transformation function, 、 and is the affine transformation coefficient, is the spiral arc length calculation function, is the polar coordinate conversion function, To find the remainder function; Remapping parameter fitting numerical solution definition: .

[0013] Furthermore, in the above-mentioned method for calculating the remapping parameters based on the calibration plate, when the preset scanning mode is concentric circle scanning, the step of performing data fitting based on the image coordinates of all marking patterns and the calibration plate coordinates to determine the remapping parameters includes: Function to convert calibration plate coordinates into image coordinates definition:

[0014] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, is the initial angle of the circle scan, and are the camera X-axis and scanning direction resolutions, is the circle radius, and are the polar coordinates of the motion platform marked respectively, and are the X and Y coordinates of the marked motion platform, and are the X and Y coordinates of the center of the circle, and are the image X and Y coordinates of the marker, is the affine transformation function, , and is the affine transformation coefficient, is the polar coordinate conversion function, To find the remainder function; Remapping parameter fitting numerical solution definition: .

[0015] Another object of the present invention is to provide a device for calculating remapping parameters based on a calibration plate, wherein the calibration plate is a wafer divided into a plurality of regions, each region being composed of respective grains with a marking pattern, wherein the marking pattern includes a data mark and a registration mark, and the device comprises: An acquisition module, used to acquire an image of the calibration plate collected in a preset scanning mode under set conditions, wherein the set conditions are that the calibration plate is placed on a motion platform, and the center of the calibration plate is aligned with the rotation center of the motion platform; A processing module, used for extracting the image coordinates of all the marking patterns on the calibration plate according to the calibration plate image by using image processing technology, wherein the image coordinates of all the marking patterns include the image coordinates of the data mark and the registration mark; The calculation module is used to calculate the calibration plate coordinates of all data marks according to the coordinates of the registration marks in the calibration plate, perform data fitting based on the image coordinates of all mark patterns and the calibration plate coordinates, and determine the remapping parameters.

[0016] Another object of the present invention is to provide a readable storage medium having a computer program stored thereon, wherein the program implements the steps of the above method when executed by a processor.

[0017] Another object of the present invention is to provide an electronic device, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of the above method when executing the program.

[0018] The present invention obtains a calibration plate image collected by a preset scanning method under set conditions, wherein the set conditions are that the calibration plate is placed on a motion platform, and the center of the calibration plate is aligned with the rotation center of the motion platform; image processing technology is used to extract the image coordinates of all marking patterns on the calibration plate according to the calibration plate image, wherein the image coordinates of all marking patterns include the image coordinates of data markings and registration markings; the calibration plate coordinates of all data markings are calculated according to the coordinates of the registration markings in the calibration plate, data fitting is performed based on the image coordinates of all marking patterns and the calibration plate coordinates, and remapping parameters are determined. The remapping parameters are calculated through steps such as scanning the calibration plate, image processing, and data fitting, without manual intervention, reducing the errors caused by manual intervention, and achieving high-precision image and coordinate remapping. The problem of low accuracy in calculating remapping parameters in the prior art is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1is a flow chart of a method for calculating remapping parameters based on a calibration plate in a first embodiment of the present invention; Figure 2 is a schematic diagram of a conventional grain pattern in a method for calculating remapping parameters based on a calibration plate in one embodiment of the present invention; Figure 3 is a schematic diagram of a special A-type grain pattern in a calculation method of remapping parameters based on a calibration plate in one embodiment of the present invention; Figure 4 is a schematic diagram of a special A1-type grain pattern in a calculation method of remapping parameters based on a calibration plate in one embodiment of the present invention; Figure 5 A schematic diagram of a special A2-type grain pattern in a calculation method of remapping parameters based on a calibration plate in one embodiment of the present invention; Figure 6 is a schematic diagram of a special B-type grain pattern in a calculation method of remapping parameters based on a calibration plate in one embodiment of the present invention; Figure 7 is a schematic diagram of a special B1 type grain pattern in a calculation method of remapping parameters based on a calibration plate in one embodiment of the present invention; Figure 8 It is a schematic diagram of a special B2 type grain pattern in a calculation method of remapping parameters based on a calibration plate in one embodiment of the present invention; Fig. 9 A schematic diagram of a special C-type grain pattern in a calculation method of remapping parameters based on a calibration plate in one embodiment of the present invention; Fig.10 Schematic diagram of A, B, and C type registration marks in a method for calculating remapping parameters based on a calibration plate in one embodiment of the present invention; Fig.11 Schematic diagram of A1, A2, A3, and A4 registration marks in a method for calculating remapping parameters based on a calibration plate in one embodiment of the present invention; Fig.12 It is a schematic diagram of determining the calibration plate coordinates of the data markers in the calculation method of the remapping parameters based on the calibration plate in one embodiment of the present invention; Fig.13 It is a structural block diagram of a calculation device for remapping parameters based on a calibration plate in a third embodiment of the present invention.

[0020] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0021] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0022] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0024] First embodiment See also Figure 1 , which shows a method for calculating remapping parameters based on a calibration plate in a first embodiment of the present invention, and the method includes steps S10 to S12.

[0025] Step S10, obtaining an image of the calibration plate under set conditions collected in a preset scanning mode, wherein the set conditions are that the calibration plate is placed on a motion platform, and the center of the calibration plate is aligned with the rotation center of the motion platform.

[0026] The calibration plate is a wafer divided into multiple areas, each area is composed of its own grains with marking patterns, the marking patterns include data marks and registration marks, and there are 8 types of grain patterns, specifically, Figures 2 to 9 , respectively: conventional, special A, special A1, special A2, special B, special B1, special B2 and special C. The above grain patterns can be decomposed into smaller unit marking patterns. The marking patterns can be divided into two categories according to their uses: data marking and registration marking. The registration marking includes three types: A, B and C. Specifically, as follows Fig.10 shown.

[0027] Furthermore, the preset scanning mode is a spiral or concentric circle scanning mode, and the calibration plate is placed on the Stage (motion platform) to ensure that the center of the wafer is aligned with the rotation center of the Stage as much as possible.

[0028] Step S11, using image processing technology to extract image coordinates of all marking patterns on the calibration plate according to the calibration plate image, wherein the image coordinates of all marking patterns include image coordinates of data marks and registration marks.

[0029] Specifically, the image processing technology is used to extract the image coordinates of all the marking patterns of the calibration plate. The coordinate points are the adjacent positions of two black squares, and are divided into data marks and registration marks according to the pattern differences. In the specific implementation, the image is thresholded based on the pixel grayscale value to extract the pattern area, and the black square area that constitutes each mark is filtered according to the area, shape and other information; the two adjacent black square areas are taken as a pair, and the contour of each black square area is extracted respectively, and the pair of points with the closest distance between the two contours is obtained by calculating the Euclidean distance, and the midpoint of the point pair is taken as the candidate coordinates; the saddle point positioning algorithm is used to improve the sub-pixel accuracy of the candidate coordinates to obtain the image coordinates of the final marking pattern.

[0030] Step S12, calculating the calibration plate coordinates of all data marks according to the coordinates of the registration marks in the calibration plate, performing data fitting based on the image coordinates of all mark patterns and the calibration plate coordinates, and determining remapping parameters.

[0031] Specifically, as shown in the following table, the A-type registration marks in the image are subdivided into four categories according to the position distribution of the black squares and white circles. Fig.11 shown.

[0032] Among them, A1 and A2 types are located on the X axis of the wafer, and A3 and A4 types are located on the Y axis of the wafer; (2) Convert the image coordinates of the A1 and A2 registration marks into stage coordinates and determine the X-axis position and direction of the wafer; (3) Convert the image coordinates of A3 and A4 registration marks into stage coordinates and determine the Y-axis position and direction of the wafer; (4) Convert the image coordinates of all data markers into Stage coordinates; (5) Specific, such as Fig.12 As shown, the circular shaded part is the registration mark, the XY axis of the calibration plate is determined according to the motion platform coordinates of the registration mark, a coordinate system is established according to the X axis and the Y axis, and the coordinates of each mark in the coordinate system are calculated, that is, the calibration plate coordinates; (6) Since the calibration plate coordinates of the B-type and C-type registration marks are known, the calibration plate coordinates of the surrounding data marks can be calculated based on these marks until all marks are covered; (7) Comprehensively compare the results of (5) and (6) to improve the accuracy of coordinate extraction of the data marker calibration plate.

[0033] Function to convert spiral scanning image coordinates to Stage coordinates definition:

[0034] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, and are the spiral coefficients, is the initial angle of the spiral scan, and are the camera X-axis and scanning direction resolutions, is the spiral arc length, and Mark Stage polar coordinates, and Mark The Stage X and Y coordinates, Calculate the function for the arc length of a spiral:

[0035] Concentric circle scanning image coordinates converted to Stage coordinates function definition:

[0036] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, is the initial angle of concentric circle scanning, and are the camera X-axis and scanning direction resolutions, is the circle radius, and They are the marked Stage polar coordinates, and are the X and Y coordinates of the marked Stage, and are the X and Y coordinates of the center of the circle respectively.

[0037] Finally, data fitting is performed based on the image coordinates of all markers and the coordinates of the calibration plate to determine the remapping parameters.

[0038] In summary, the calculation method of the remapping parameters based on the calibration plate in the above embodiment of the present invention is to obtain the calibration plate image of the calibration plate collected in a preset scanning mode under set conditions, wherein the set conditions are that the calibration plate is placed on a motion platform, and the center of the calibration plate is aligned with the rotation center of the motion platform; the image coordinates of all the marking patterns on the calibration plate are extracted according to the calibration plate image using image processing technology, wherein the image coordinates of all the marking patterns include the image coordinates of the data mark and the registration mark; the calibration plate coordinates of all the data marks are calculated according to the coordinates of the registration mark in the calibration plate, and data fitting is performed based on the image coordinates of all the marking patterns and the calibration plate coordinates to determine the remapping parameters, and the remapping parameters are calculated by scanning the calibration plate, image processing, data fitting and other steps, without manual intervention, reducing the errors caused by manual intervention, and realizing high-precision image and coordinate remapping. The problem of low accuracy in calculating remapping parameters in the prior art is solved.

[0039] Second embodiment This embodiment also proposes a method for calculating remapping parameters based on a calibration plate. The difference between the method for calculating remapping parameters based on a calibration plate in this embodiment and the method for calculating remapping parameters based on a calibration plate in the first embodiment is that: When the preset scanning mode is spiral scanning, the calibration plate coordinates are converted into image coordinates by the function definition:

[0040] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, and are the spiral coefficients, is the initial angle of the spiral scan, and are the camera X-axis and scanning direction resolutions, and They are the marked Stage polar coordinates, and are the X and Y coordinates of the marked Stage, and are the image X and Y coordinates of the marker, is the affine transformation function, , and is the affine transformation coefficient, is the spiral arc length calculation function, is the polar coordinate conversion function, To find the remainder function.

[0041] Remapping parameter fitting numerical solution definition:

[0042] When the preset scanning mode is concentric circle scanning, the calibration plate coordinates are converted into image coordinates function definition:

[0043] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, is the initial angle of the circle scan, and are the camera X-axis and scanning direction resolutions, is the circle radius, and They are the marked Stage polar coordinates, and are the X and Y coordinates of the marked Stage, and are the X and Y coordinates of the center of the circle, and are the image X and Y coordinates of the marker, is the affine transformation function, , and is the affine transformation coefficient, is the polar coordinate conversion function, To find the remainder function.

[0044] Remapping parameter fitting numerical solution definition:

[0045] In summary, the calculation method of the remapping parameters based on the calibration plate in the above embodiment of the present invention is to obtain the calibration plate image of the calibration plate collected in a preset scanning mode under set conditions, wherein the set conditions are that the calibration plate is placed on a motion platform, and the center of the calibration plate is aligned with the rotation center of the motion platform; the image coordinates of all the marking patterns on the calibration plate are extracted according to the calibration plate image using image processing technology, wherein the image coordinates of all the marking patterns include the image coordinates of the data mark and the registration mark; the calibration plate coordinates of all the data marks are calculated according to the coordinates of the registration mark in the calibration plate, and data fitting is performed based on the image coordinates of all the marking patterns and the calibration plate coordinates to determine the remapping parameters, and the remapping parameters are calculated by scanning the calibration plate, image processing, data fitting and other steps, without manual intervention, reducing the errors caused by manual intervention, and realizing high-precision image and coordinate remapping. The problem of low accuracy in calculating remapping parameters in the prior art is solved.

[0046] Third embodiment See also Fig.13 , shown is a calculation device for remapping parameters based on a calibration plate according to a fourth embodiment of the present invention, wherein the calibration plate is a wafer divided into a plurality of regions, each region being composed of respective grains with a marking pattern, wherein the marking pattern includes a data mark and a registration mark, and the device includes: The acquisition module 100 is used to acquire an image of the calibration plate collected in a preset scanning mode under set conditions, wherein the set conditions are that the calibration plate is placed on a motion platform, and the center of the calibration plate is aligned with the rotation center of the motion platform; A processing module 200 is used to extract the image coordinates of all the marking patterns on the calibration plate according to the calibration plate image by using image processing technology, wherein the image coordinates of all the marking patterns include the image coordinates of the data mark and the registration mark; The calculation module 300 is used to calculate the calibration plate coordinates of all data marks according to the coordinates of the registration marks in the calibration plate, perform data fitting based on the image coordinates of all mark patterns and the calibration plate coordinates, and determine the remapping parameters.

[0047] Furthermore, in the above-mentioned calibration plate-based remapping parameter calculation device, the step of extracting the image coordinates of all marking patterns on the calibration plate according to the calibration plate image using image processing technology comprises: The calibration plate image is thresholded based on the pixel gray value to extract the pattern area, and the black square area that constitutes each mark is filtered according to the area, shape and other information; Take two adjacent black square areas as a pair, extract the contour of each black square area respectively, calculate the Euclidean distance to get a pair of points with the closest distance between the two contours, and use the midpoint of the point pair as the candidate coordinate; The saddle point positioning algorithm is used to improve the sub-pixel accuracy of the candidate coordinates to obtain the image coordinates of the corresponding marking pattern.

[0048] Furthermore, in the above-mentioned calibration plate-based remapping parameter calculation device, the step of calculating the calibration plate coordinates of all data marks according to the coordinates of the registration marks in the calibration plate comprises: The calibration plate image is thresholded based on the pixel gray value to extract the pattern area, and the black and white circular areas are filtered according to the area, shape and other information; Determine the type of registration mark according to the number and position distribution of the circular areas, and determine the X-axis and Y-axis positions and directions corresponding to the calibration plate according to the type of registration mark; The image coordinates of all data markers are converted into motion platform coordinates, a coordinate system is established according to the X-axis and Y-axis, and the coordinates of each data marker in the coordinate system are calculated, namely, the calibration plate coordinates.

[0049] Furthermore, in the above-mentioned calculation device of the remapping parameters based on the calibration plate, when the preset scanning mode is spiral scanning, the function of converting the image coordinates of all data marks into the motion platform coordinates is defined as: ; in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, and are the spiral coefficients, is the initial angle of the spiral scan, and are the camera X-axis and scanning direction resolutions, is the spiral arc length, and Mark The polar coordinates of the motion platform, and Mark The X and Y coordinates of the motion platform.

[0050] Furthermore, in the above-mentioned calculation device of the remapping parameters based on the calibration plate, when the preset scanning mode is concentric circle scanning, the function of converting the image coordinates of all data marks into the motion platform coordinates is defined as:

[0051] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, is the initial angle of concentric circle scanning, and are the camera X-axis and scanning direction resolutions, is the circle radius, and are the polar coordinates of the motion platform marked respectively, and are the X and Y coordinates of the marked motion platform, and are the X and Y coordinates of the center of the circle respectively.

[0052] Furthermore, in the above-mentioned calculation device for remapping parameters based on the calibration plate, when the preset scanning mode is spiral scanning, the step of performing data fitting based on the image coordinates of all marking patterns and the calibration plate coordinates to determine the remapping parameters includes: Function to convert calibration plate coordinates into image coordinates definition:

[0053] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, and are the spiral coefficients, is the initial angle of the spiral scan, and are the camera X-axis and scanning direction resolutions, and are the polar coordinates of the motion platform marked respectively, and are the X and Y coordinates of the marked motion platform, and are the image X and Y coordinates of the marker, is the affine transformation function, , and is the affine transformation coefficient, is the spiral arc length calculation function, is the polar coordinate conversion function, To find the remainder function; Remapping parameter fitting numerical solution definition: .

[0054] Furthermore, in the above-mentioned calculation device for remapping parameters based on the calibration plate, when the preset scanning mode is concentric circle scanning, the step of performing data fitting based on the image coordinates of all marking patterns and the calibration plate coordinates to determine the remapping parameters includes: Function to convert calibration plate coordinates into image coordinates definition:

[0055] in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, is the initial angle of the circle scan, and are the camera X-axis and scanning direction resolutions, is the circle radius, and are the polar coordinates of the motion platform marked respectively, and are the X and Y coordinates of the marked motion platform, and are the X and Y coordinates of the center of the circle, and are the image X and Y coordinates of the marker, is the affine transformation function, , and is the affine transformation coefficient, is the polar coordinate conversion function, To find the remainder function; Remapping parameter fitting numerical solution definition: .

[0056] The functions or operation steps implemented when the above modules are executed are substantially the same as those in the above method embodiments, and will not be repeated here.

[0057] Fourth embodiment Another aspect of the present invention further provides a readable storage medium having a computer program stored thereon, and when the program is executed by a processor, the steps of the method described in any one of the first to second embodiments above are implemented.

[0058] Fifth embodiment Another aspect of the present invention provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and running on the processor, and when the processor executes the program, the steps of the method described in any one of the first to second embodiments above are implemented.

[0059] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0060] Those skilled in the art will appreciate that the logic and / or steps represented in the flowchart or otherwise described herein, for example, may be considered as an ordered list of executable instructions for implementing logical functions, and may be specifically implemented in any computer-readable storage medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For purposes of this specification, a "computer-readable storage medium" may be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0061] More specific examples (a non-exhaustive list) of computer-readable storage media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable storage medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0062] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or a combination thereof: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0063] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0064] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for calculating remapping parameters based on a calibration plate, characterized in that: The calibration plate is a wafer divided into a plurality of regions, each region is composed of respective crystal grains with a marking pattern, the marking pattern includes a data mark and a registration mark, and the method includes: Acquire an image of the calibration plate collected in a preset scanning mode under set conditions, wherein the set conditions are that the calibration plate is placed on a motion platform, and the center of the calibration plate is aligned with the rotation center of the motion platform; Extracting the image coordinates of all the marking patterns on the calibration plate according to the calibration plate image by using image processing technology, wherein the image coordinates of all the marking patterns include the image coordinates of the data marks and the registration marks; The calibration plate coordinates of all data markers are calculated according to the coordinates of the registration markers in the calibration plate, and data fitting is performed based on the image coordinates of all marker patterns and the calibration plate coordinates to determine the remapping parameters.

2. The method for calculating the remapping parameters based on the calibration plate according to claim 1, characterized in that: The step of extracting the image coordinates of all marking patterns on the calibration plate according to the calibration plate image by using image processing technology comprises: The calibration plate image is thresholded based on the pixel gray value to extract the pattern area, and the black square area that constitutes each mark is filtered according to the area, shape and other information; Take two adjacent black square areas as a pair, extract the contour of each black square area respectively, calculate the Euclidean distance to get a pair of points with the closest distance between the two contours, and use the midpoint of the point pair as the candidate coordinate; The saddle point positioning algorithm is used to improve the sub-pixel accuracy of the candidate coordinates to obtain the image coordinates of the corresponding marking pattern.

3. The method for calculating the remapping parameters based on the calibration plate according to claim 2, characterized in that: The step of calculating the calibration plate coordinates of all data marks according to the coordinates of the registration marks in the calibration plate comprises: The calibration plate image is thresholded based on the pixel gray value to extract the pattern area, and the black and white circular areas are filtered according to the area, shape and other information; Determine the type of registration mark according to the number and position distribution of the circular areas, and determine the X-axis and Y-axis positions and directions corresponding to the calibration plate according to the type of registration mark; The image coordinates of all data markers are converted into motion platform coordinates, a coordinate system is established according to the X-axis and Y-axis, and the coordinates of each data marker in the coordinate system are calculated, namely, the calibration plate coordinates.

4. The method for calculating the remapping parameters based on the calibration plate according to claim 3, characterized in that: When the preset scanning mode is spiral scanning, the function of converting the image coordinates of all data marks into the motion platform coordinates is defined as: ； in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, and are the spiral coefficients, is the initial angle of the spiral scan, and are the camera X-axis and scanning direction resolutions, is the spiral arc length, and Mark The polar coordinates of the motion platform, and Mark The X and Y coordinates of the motion platform.

5. The method for calculating the remapping parameters based on the calibration plate according to claim 4, characterized in that: When the preset scanning mode is concentric circle scanning, the function of converting the image coordinates of all data marks into the motion platform coordinates is defined as: in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, is the initial angle of concentric circle scanning, and are the camera X-axis and scanning direction resolutions, is the circle radius, and are the polar coordinates of the motion platform marked respectively, and are the X and Y coordinates of the marked motion platform, and are the X and Y coordinates of the center of the circle respectively.

6. The method for calculating the remapping parameters based on the calibration plate according to claim 1, characterized in that: When the preset scanning mode is spiral scanning, the step of performing data fitting based on the image coordinates of all marking patterns and the coordinates of the calibration plate to determine the remapping parameters includes: Function to convert calibration plate coordinates into image coordinates definition: in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, and are the spiral coefficients, is the initial angle of the spiral scan, and are the camera X-axis and scanning direction resolutions, and are the polar coordinates of the motion platform marked respectively, and are the X and Y coordinates of the marked motion platform, and are the image X and Y coordinates of the marker, is the affine transformation function, , and is the affine transformation coefficient, is the spiral arc length calculation function, is the polar coordinate conversion function, To find the remainder function; Remapping parameter fitting numerical solution definition: 。 7. The method for calculating the remapping parameters based on the calibration plate according to claim 1, characterized in that: When the preset scanning mode is concentric circle scanning, the step of performing data fitting based on the image coordinates of all marking patterns and the coordinates of the calibration plate to determine the remapping parameters includes: Function to convert calibration plate coordinates into image coordinates definition: in, and Mark The image X and Y coordinates, and are the X and Y coordinates in the image stitching coordinate system, and are the image width and height, is the image number, is the initial angle of the circle scan, and are the camera X-axis and scanning direction resolutions, is the circle radius, and are the polar coordinates of the motion platform marked respectively, and are the X and Y coordinates of the marked motion platform, and are the X and Y coordinates of the center of the circle, and are the image X and Y coordinates of the marker, is the affine transformation function, , and is the affine transformation coefficient, is the polar coordinate conversion function, To find the remainder function; Remapping parameter fitting numerical solution definition: 。 8. A device for calculating remapping parameters based on a calibration plate, characterized in that: The calibration plate is a wafer divided into a plurality of regions, each region is composed of respective crystal grains with a marking pattern, the marking pattern includes a data mark and a registration mark, and the device includes: An acquisition module, used to acquire an image of the calibration plate collected in a preset scanning mode under set conditions, wherein the set conditions are that the calibration plate is placed on a motion platform, and the center of the calibration plate is aligned with the rotation center of the motion platform; A processing module, used for extracting the image coordinates of all the marking patterns on the calibration plate according to the calibration plate image by using image processing technology, wherein the image coordinates of all the marking patterns include the image coordinates of the data mark and the registration mark; The calculation module is used to calculate the calibration plate coordinates of all data marks according to the coordinates of the registration marks in the calibration plate, perform data fitting based on the image coordinates of all mark patterns and the calibration plate coordinates, and determine the remapping parameters.

9. A readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. An electronic device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and running on the processor, wherein when the processor executes the program, the steps of the method according to any one of claims 1 to 7 are implemented.

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