High-precision alignment method and equipment for laminated steel

Abstract

The invention provides a high-precision alignment method and equipment for laminated iron, and relates to the technical field of laminated iron processing. Wire grid moire fringe marking and concentric circle moire fringe marking are conducted on a substrate and a laminated film, composite marking is achieved, the phase difference of the film is calculated and analyzed by collecting wire grid moire fringe image data, and the alignment precision of the laminated iron is improved. The method comprises the following steps: collecting concentric circle moire fringe image data, fitting a circle center coordinate and a wire grating angle by using Hough transformation to obtain a rotation deviation, and carrying out deviation coupling on the rotation deviation, the transverse deviation and the longitudinal deviation to generate a deviation coupling matrix. The deviation coupling matrix is used for compensating and adjusting the laminating position and compensating errors, high-precision decoupling detection and dynamic correction of translation deviation and rotation deviation are achieved, the transverse, longitudinal and rotation precision is greatly improved, the effective area occupied by the marking size on a base plate is small, and the method is more suitable for production of laminated steel with narrow breadth and high-density typesetting.

Description

Technical Field

[0001] The present invention relates to the technical field of coated iron processing, and in particular to a high-precision alignment method and equipment for coated iron. Background Art

[0002] Coated iron, a metal-based composite material, combines the strength of metal with the corrosion resistance and insulation properties of thin films by laminating a polymer film on a steel plate. It is widely used in food cans, pharmaceutical packaging, and 5G electronic component substrates. As downstream industries upgrade towards miniaturization and precision, stringent requirements are placed on the alignment accuracy of coated iron. Existing technology places circular or cross-shaped marks on the substrate and film surfaces, and uses a visual camera to identify the center coordinate difference of the marks and calculate the deviation. However, achieving submicron accuracy is difficult.

[0003] In the field of microelectronics packaging, the coated iron used for chip carriers must meet the requirements of lateral / longitudinal deviation between the film and the substrate ≤0.1μm and rotational deviation ≤0.01° to avoid misalignment of circuit connections; in the field of pharmaceutical and food anti-counterfeiting packaging, high-precision alignment can ensure that the film coating evenly covers surface defects of the substrate, complete the preparation of complex anti-counterfeiting patterns, and greatly enhance product value and application scope.

[0004] The existing technology of coated iron cannot achieve independent detection of the X-axis, Y-axis and rotation during processing, resulting in "translation-rotation" linkage errors during adjustment, and when the mark position deviates, the existing method lacks an effective compensation mechanism.

[0005] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the Invention

[0006] The object of the present invention is to provide a high-precision alignment method and equipment for coated iron to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A high-precision alignment method for coated iron, comprising the following steps:

[0009] S1. During the coated iron process, adding wire grid moiré fringe marks to the film and substrate, and adding concentric circle moiré fringe marks to the film and substrate, wherein the wire grid moiré fringe marks and the concentric circle moiré fringe marks are both used to position the substrate and the film;

[0010] S2. Completely capture the wire grid moiré fringe mark using a linear array camera, collect image data of the wire grid moiré fringe mark, obtain the fundamental frequency signal of the moiré fringe through Fourier transform, perform correlation analysis on the fundamental frequency signal, generate the phase difference of the wire grid moiré fringe mark between the film and the substrate, perform correlation analysis on the phase difference, and generate lateral deviation and longitudinal deviation;

[0011] S3. Collect concentric moiré fringe mark image data using an area array camera, fit the center coordinates of the concentric moiré fringe mark and the wire grid angle θ using Hough transform, and further analyze to generate a rotational deviation Δθ. The wire grid angle θ is the angle of the spoke-shaped wire grid of the fitted concentric moiré fringe mark. The rotational deviation Δθ is used to reflect the rotational deviation angle between the substrate and the film.

[0012] S4, performing correlation analysis on the concentric moiré fringe mark grid angle θ, rotation deviation Δθ, lateral deviation and longitudinal deviation to generate a deviation coupling matrix, which is used to reflect the coating offset and deflection during the coating iron process;

[0013] S5. Adjust the film position by translation and rotation according to the deviation coupling matrix until the calibration is determined to be complete.

[0014] Furthermore, each substrate and the film have the wire grid moiré fringe marks at the corresponding positions at both ends of the edge, and the wire grid moiré fringe marks are orthogonal wire grids, and the orthogonal wire grids include transverse wire grids and longitudinal wire grids, and the transverse wire grids are parallel to the film transmission direction, with a period of P x =5μm, the transverse wire grid is used to detect the transverse deviation ΔX, the longitudinal wire grid is perpendicular to the film transmission direction, the period P y =5μm, the longitudinal line grid is used to detect the longitudinal deviation ΔY, the grid line width is 2.5μm, and the edge roughness is less than or equal to 50nm.

[0015] Furthermore, concentric moiré fringe marks are added to the corresponding center positions of each substrate and the film. The concentric moiré fringe marks include 360 radial grating lines, the radial grating line angle is 1 degree, the inner diameter R1 = 10 mm, the outer diameter R2 = 12 mm, and the angular positioning accuracy of the spoke-shaped grating lines is ±0.001 degrees. The concentric moiré fringe marks are used to detect rotational deviation Δθ.

[0016] Furthermore, the resolution of the linear array camera is 12K, the scanning frequency is 10kHz, and a two-dimensional Fourier transform is applied to the collected image data of the line grid moiré fringe mark to obtain the fundamental frequency signal of the moiré fringe, based on the formula:

[0017]

[0018] Wherein, F(u, v) is the fundamental frequency signal of the image data of the line grid moiré fringe mark, f(x, y) is the time domain image of the image data of the line grid moiré fringe mark, u and v are frequency variables, x and y represent the horizontal and vertical coordinates of each pixel in the image data of the line grid moiré fringe mark, f(x, y) is the image function of the image data of the line grid moiré fringe mark, which represents the grayscale value of the pixel at the plane coordinate (x, y), (u, v) is the frequency domain coordinate, which represents different frequency components, u represents the frequency in the horizontal direction, v represents the frequency in the vertical direction, F(u, v) is the image function in the frequency domain, which represents the frequency component at the frequency coordinate (u, v), and j is an imaginary number;

[0019] The fundamental frequency signal is correlated and the phase difference of the line grid moiré fringe mark between the film and the substrate is generated based on the following formula:

[0020]

[0021] in, is the lateral phase deviation, is the longitudinal phase deviation, arg(F x )、arg(F y ) represent the phase information of the horizontal and vertical Fourier transform results respectively, where

[0022] Correlation analysis is performed on the phase difference to generate the lateral deviation ΔX and longitudinal deviation ΔY based on the following formula:

[0023]

[0024] The lateral deviation ΔX is used to reflect the lateral deviation distance of the wire grid moiré fringe marks on the substrate and the film, and the longitudinal deviation ΔY is used to reflect the longitudinal deviation distance of the wire grid moiré fringe marks on the substrate and the film.

[0025] Furthermore, the resolution of the area array camera is 16MP, and Hough transform is applied to the collected concentric circle moiré fringe mark image data to identify the circular edge and obtain the coordinates of the circle center and the concentric circle moiré fringe mark line grid angle θ.

[0026] Furthermore, a correlation analysis is performed on the wire grid angle θ to generate the rotation deviation Δθ, based on the formula:

[0027]

[0028] Among them, the wire grid angle is the difference between the angle of the concentric moiré fringe marked spoke wire grid on the film and the angle of the concentric moiré fringe marked spoke wire grid on the substrate, N is the total number of spoke wire grids of the concentric moiré fringe marked wire grid, and ΔN is the number of wire grids that produce phase difference in the concentric moiré fringe marked spoke wire grid.

[0029] Furthermore, the correlation analysis of the concentric moiré fringe marker line grid angle θ, rotation deviation Δθ, lateral deviation and longitudinal deviation is performed to generate the deviation coupling matrix based on the formula:

[0030]

[0031] Where R is the radius of the concentric moiré fringe marker, ΔX′ is the lateral offset of the coating, ΔY′ is the longitudinal offset of the coating, and Δθ′ is the deflection of the coating, with the unit being degrees.

[0032] Furthermore, an air-floating guide rail and a voice coil motor are used to drive the translation of the coating, and the coating position is adjusted according to ΔX′ and ΔY′ until the wire grid moiré marks on the coating coincide with the wire grid moiré marks on the substrate. The coating angle is adjusted by a magnetic levitation rotating table, and the adjustment angle is Δθ′. During the adjustment process, the contrast between the wire grid and the spoke-mounted wire grid is fed back in real time. When the contrast is greater than or equal to 90% and the center coordinate deviation is less than 0.02μm, the alignment is determined to be complete.

[0033] The present invention also provides a high-precision alignment device for coated iron, which is used to perform a high-precision alignment method for coated iron, comprising:

[0034] Marking module, used to add wire grid moiré fringe marks to the film and substrate during the coated iron process, and to add concentric circle moiré fringe marks to the film and substrate;

[0035] The wire grid analysis module is used to completely capture the wire grid moiré fringe marks through a linear array camera, continuously collect image data of the wire grid moiré fringe marks, obtain the fundamental frequency signal of the moiré fringe through Fourier transform, perform correlation analysis on the fundamental frequency signal, generate the phase difference of the wire grid moiré fringe marks between the film and the substrate, perform correlation analysis on the phase difference, and generate lateral deviation and longitudinal deviation;

[0036] The circular grating analysis module is used to collect concentric circular moiré fringe mark image data through an area array camera, fit the concentric circular moiré fringe mark center coordinates and the line grating angle θ through Hough transform, and further analyze and generate a rotation deviation Δθ. The line grating angle θ is the angle of the spoke-shaped line grating of the fitted concentric circular moiré fringe mark;

[0037] Deviation coupling module, used to perform correlation analysis on the angle θ, rotation deviation Δθ, lateral deviation and longitudinal deviation of the concentric moiré fringe marker grid to generate a deviation coupling matrix;

[0038] Adjustment module, used for translation and rotation adjustment of lamination position.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention realizes composite marking by marking the substrate and the coating with wire grid moiré fringes and concentric circle moiré fringes, calculates and analyzes the phase difference of the film by collecting wire grid moiré fringes image data, and further calculates the lateral deviation and longitudinal deviation. At the same time, by collecting the concentric circle moiré fringes image data, the center coordinates and the wire grid angle are fitted using Hough transform, and further the rotational deviation is obtained. The rotational deviation, lateral deviation and longitudinal deviation are deviation-coupled to generate a deviation coupling matrix, and the coating position is compensated and adjusted by the deviation coupling matrix to compensate for the error, thereby realizing high-precision decoupling detection and dynamic correction of translational deviation and rotational deviation, greatly improving the lateral, longitudinal and rotational accuracy. In addition, the marking size of the present invention occupies a small effective area of the substrate, and is more suitable for the production of coated iron for narrow format and high-density typesetting. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Schematic diagram of the overall method flow of the present invention;

[0042] Figure 2 This is a schematic diagram of the arrangement module of the present invention;

[0043] Figure 3 Schematic diagram of the moiré fringe marking of the present invention;

[0044] Figure 4 This is a schematic diagram of the coated iron of the present invention;

[0045] Figure 5 These are 30 groups of alignment recognition results randomly selected by the present invention. DETAILED DESCRIPTION

[0046] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0047] It should be noted that, unless otherwise defined, the technical or scientific terms used in the present invention should have the usual meanings understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0048] Example:

[0049] See also Figure 1 , the present invention provides a technical solution:

[0050] A high-precision alignment method for coated iron, comprising the following steps:

[0051] Step 1: During the coated iron process, wire grid moiré fringe marks are added to the film and substrate, and concentric circle moiré fringe marks are added to the film and substrate. The wire grid moiré fringe marks and concentric circle moiré fringe marks are both used to position the substrate and the film;

[0052] The corresponding positions of the edges of each substrate and the two ends of the film include the wire grid moiré fringe marks, and the wire grid moiré fringe marks are orthogonal wire grids. The orthogonal wire grids include transverse wire grids and longitudinal wire grids. The transverse wire grids are parallel to the transmission direction of the coating, with a period of P x =5μm, the transverse wire grid is used to detect the transverse deviation ΔX, the longitudinal wire grid is perpendicular to the film transmission direction, the period P y =5μm, the longitudinal line grid is used to detect the longitudinal deviation ΔY, the grid line width is 2.5μm, and the edge roughness is less than or equal to 50nm. x =5μm is the interval between adjacent transverse wire grids, and the period P y =5μm is the interval between adjacent longitudinal wire grids.

[0053] Step 2: Completely capture the wire grid moiré fringe mark using a linear array camera, collect image data of the wire grid moiré fringe mark, obtain the fundamental frequency signal of the moiré fringe through Fourier transform, perform correlation analysis on the fundamental frequency signal, generate the phase difference of the wire grid moiré fringe mark between the film and the substrate, perform correlation analysis on the phase difference, and generate the lateral deviation and longitudinal deviation;

[0054] Concentric moiré fringe marks are added to the corresponding center positions of each substrate and film. The concentric moiré fringe marks include 360 radial grating lines with an included angle of 1 degree, an inner diameter R1 = 10 mm, an outer diameter R2 = 12 mm, and an angular positioning accuracy of ±0.001 degrees for the spoke-shaped grating lines. The concentric moiré fringe marks are used to detect rotational deviation Δθ.

[0055] The resolution of the linear array camera is 12K and the scanning frequency is 10kHz. A two-dimensional Fourier transform is applied to the collected image data of the line grid moiré fringe mark to obtain the fundamental frequency signal of the moiré fringe. The formula is:

[0056]

[0057] Wherein, F(u, v) is the fundamental frequency signal of the image data of the line grid moiré fringe mark, f(x, y) is the time domain image of the image data of the line grid moiré fringe mark, and u and v are frequency variables;

[0058] (x, y) are spatial domain coordinates, representing the position of a point in the image on a plane. x and y represent the horizontal and vertical coordinates of each pixel in the image data of the line grid moiré fringe marker. f(x, y) is an image function in the spatial domain, representing the grayscale value of the pixel at the plane coordinates (x, y). (u, v) are frequency domain coordinates, representing different frequency components. u represents the horizontal frequency, and v represents the vertical frequency. F(u, v) is an image function in the frequency domain, representing the frequency component at the frequency coordinates (u, v). j is an imaginary number.

[0059] By performing a two-dimensional Fourier transform on an image, we can extract frequency information, including both low-frequency and high-frequency components. In the frequency domain, we can identify the fundamental frequency signal associated with the moiré fringes by examining the amplitude spectrum of the frequency components. By calculating the phase information in the frequency domain, we can understand the relative position and variation of the moiré fringes, thereby calculating the phase difference between the moiré marks on the film and the substrate.

[0060] The fundamental frequency signal is correlated and the phase difference of the line grid moiré fringe mark between the film and the substrate is generated based on the following formula:

[0061]

[0062] in, is the lateral phase deviation, is the longitudinal phase deviation, arg(F x )、arg(F y ) represent the phase information of the horizontal and vertical Fourier transform results respectively, where

[0063] Correlation analysis is performed on the phase difference to generate the lateral deviation ΔX and longitudinal deviation ΔY based on the following formula:

[0064]

[0065] The lateral deviation ΔX is used to reflect the lateral deviation distance of the wire grid moiré fringe marks on the substrate and the film, and the longitudinal deviation ΔY is used to reflect the longitudinal deviation distance of the wire grid moiré fringe marks on the substrate and the film.

[0066] Step 3: Acquire concentric moiré fringe mark image data using an area array camera, fit the concentric moiré fringe mark center coordinates and the line grid angle θ using Hough transform, and further analyze to generate a rotational deviation Δθ. The line grid angle θ is the angle of the spoke-shaped line grid of the fitted concentric moiré fringe mark. The rotational deviation Δθ is used to reflect the rotational deviation angle between the substrate and the film.

[0067] The area array camera has a resolution of 16MP. Hough transform is applied to the collected concentric circle moiré fringe mark image data. Through Hough transform, the existence of circles can be detected in the image data, and the center position and radius R of the circle can be calculated by fitting. At the same time, the circular edge can also be identified to obtain the coordinates of the center of the circle and the spoke-shaped line grid angle θ of the concentric circle moiré fringe mark.

[0068] The spoke-shaped wire grid angle θ is the angle between the corresponding spoke-shaped wire grids on the substrate and on the film in the concentric moiré fringe mark image data.

[0069] Correlation analysis of the wire grid angle θ is performed to generate the rotation deviation Δθ based on the formula:

[0070]

[0071] Among them, the wire grid angle is the difference between the angle of the concentric moiré fringe marked spoke wire grid on the film and the angle of the concentric moiré fringe marked spoke wire grid on the substrate, N is the total number of spoke wire grids of the concentric moiré fringe marked wire grid, and ΔN is the number of wire grids that produce phase difference in the concentric moiré fringe marked spoke wire grid.

[0072] Step 4: perform correlation analysis on the concentric moiré fringe mark grid angle θ, rotation deviation Δθ, lateral deviation, and longitudinal deviation to generate a deviation coupling matrix. The deviation coupling matrix is used to reflect the coating offset and deflection during the coating iron process.

[0073] The correlation analysis of the concentric moiré fringe marker line grid angle θ, rotation deviation Δθ, lateral deviation and longitudinal deviation is performed to generate the deviation coupling matrix based on the formula:

[0074]

[0075] Where R is the radius of the concentric moiré fringe marker, ΔX′ is the lateral offset of the coating, ΔY′ is the longitudinal offset of the coating, and Δθ′ is the deflection of the coating, in degrees. The deviation coupling matrix is used to describe the mutual influence between different deviations in the system, especially the coupling relationship between translational deviation and rotational deviation in high-precision alignment systems. In the above formula, the vector on the left side of the equal sign represents the deviation that needs to be corrected. represents the original deviation obtained by measurement, This figure represents the coupling relationship between translational and rotational deviations. In the first row, the calculation of ΔX′ is directly affected only by ΔX, with the effect of the rotation angle adjusted by -R sinθ. In the second row, the calculation of ΔY′ is directly affected only by ΔY, with the effect of the rotation angle adjusted by R cosθ. In the third row, Δθ′ is directly related only to Δθ and is unaffected by translational deviation. The coupling matrix compensates for the effect of rotational deviation on translational detection.

[0076] Step 5: Adjust the film position by translation and rotation according to the deviation coupling matrix until the calibration is determined to be complete.

[0077] An air-floating guide rail and a voice coil motor are used to drive the film translation. The film position is adjusted according to ΔX′ and ΔY′ until the wire grid moiré marks on the film coincide with the wire grid moiré marks on the substrate. The film angle is adjusted by a magnetic levitation rotary table with an adjustment amount of Δθ′. During the adjustment process, the contrast between the wire grid and the spoke-mounted wire grid is fed back in real time. When the contrast is greater than or equal to 90% and the center coordinate deviation is less than 0.02μm, the alignment is considered complete.

[0078] After the film is driven to translate by the air-floating guide rail and the voice coil motor, the alignment is determined to be accurate when the deviation of the center coordinates of the concentric circle moiré fringe mark image data and the center coordinates on the substrate is less than 0.02 μm, and the contrast of the image data is greater than or equal to 90%. If it is inaccurate, repeat steps 2-5.

[0079] Reference Figure 2 The present invention also provides a high-precision alignment device for coated iron, which is used to perform a high-precision alignment method for coated iron, comprising:

[0080] Marking module, used to add wire grid moiré fringe marks to the film and substrate during the coated iron process, and to add concentric circle moiré fringe marks to the film and substrate;

[0081] The wire grid analysis module is used to completely capture the wire grid moiré fringe marks through a linear array camera, continuously collect image data of the wire grid moiré fringe marks, obtain the fundamental frequency signal of the moiré fringe through Fourier transform, perform correlation analysis on the fundamental frequency signal, generate the phase difference of the wire grid moiré fringe marks between the film and the substrate, perform correlation analysis on the phase difference, and generate lateral deviation and longitudinal deviation;

[0082] The circular grating analysis module is used to collect concentric circular moiré fringe mark image data through an area array camera, fit the concentric circular moiré fringe mark center coordinates and the line grating angle θ through Hough transform, and further analyze and generate a rotation deviation Δθ. The line grating angle θ is the angle of the spoke-shaped line grating of the fitted concentric circular moiré fringe mark;

[0083] Deviation coupling module, used to perform correlation analysis on the angle θ, rotation deviation Δθ, lateral deviation and longitudinal deviation of the concentric moiré fringe marker grid to generate a deviation coupling matrix;

[0084] Adjustment module, used for translation and rotation adjustment of lamination position.

[0085] See Figure 3 , the left side is a schematic diagram of the wire grid moiré fringe marks and the concentric circle moiré fringe marks on the coating, and the right side is a schematic diagram of the wire grid moiré fringe marks and the concentric circle moiré fringe marks on the substrate, where the wire grid moiré fringe marks are located at the edges on both sides and the concentric circle moiré fringe marks are located in the center.

[0086] See Figure 4 , where both the line array camera and the area array camera use independent light sources to improve brightness and ensure the accuracy of image data reception.

[0087] In this embodiment, 30 consecutive sets of recognition alignment calculation results are randomly selected, as shown in the following table:

[0088] Table 1

[0089]

[0090]

[0091] Reference Figure 5 , Figure 5 The lateral offset, longitudinal offset and rotational offset angle of the coating in each group are clearly displayed, and the center coordinate deviation in the 14th, 17th, 24th, 25th and 29th groups is greater than or equal to 0.02μm. The coating is then adjusted and reset according to the lateral offset, longitudinal offset and rotational offset angle to improve the accuracy of the coating.

[0092] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0093] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software depends on the specific application and design constraints of the technical solution.

[0094] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, and may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment as needed.

[0095] The above is only a specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the scope of protection of the present application.

Claims

1. A high-precision alignment method for coated iron, characterized in that: The specific steps include: S1. During the coated iron process, adding wire grid moiré fringe marks to the film and substrate, and adding concentric circle moiré fringe marks to the film and substrate, wherein the wire grid moiré fringe marks and the concentric circle moiré fringe marks are both used to position the substrate and the film; S2. Completely capture the wire grid moiré fringe mark using a linear array camera, collect image data of the wire grid moiré fringe mark, obtain the fundamental frequency signal of the moiré fringe through Fourier transform, perform correlation analysis on the fundamental frequency signal, generate the phase difference of the wire grid moiré fringe mark between the film and the substrate, perform correlation analysis on the phase difference, and generate lateral deviation and longitudinal deviation; S3. Collect concentric moiré fringe mark image data using an area array camera, fit the center coordinates of the concentric moiré fringe mark and the wire grid angle θ using Hough transform, and further analyze to generate a rotational deviation Δθ. The wire grid angle θ is the angle of the spoke-shaped wire grid of the fitted concentric moiré fringe mark. The rotational deviation Δθ is used to reflect the rotational deviation angle between the substrate and the film. S4, performing correlation analysis on the concentric moiré fringe mark grid angle θ, rotation deviation Δθ, lateral deviation and longitudinal deviation to generate a deviation coupling matrix, which is used to reflect the coating offset and deflection during the coating iron process; S5. Adjust the film position by translation and rotation according to the deviation coupling matrix until the calibration is determined to be complete.

2. The high-precision alignment method for coated iron according to claim 1, characterized in that: The corresponding positions of the edges of each substrate and the two ends of the film include the wire grid moiré fringe marks, and the wire grid moiré fringe marks are orthogonal wire grids. The orthogonal wire grids include transverse wire grids and longitudinal wire grids. The transverse wire grids are parallel to the transmission direction of the coating, with a period of P x =5μm, the transverse wire grid is used to detect the transverse deviation ΔX, the longitudinal wire grid is perpendicular to the film transmission direction, the period P y =5μm, the longitudinal line grid is used to detect the longitudinal deviation ΔY, the grid line width is 2.5μm, and the edge roughness is less than or equal to 50nm.

3. The high-precision alignment method for coated iron according to claim 2, characterized in that: Concentric moiré fringe marks are added to the corresponding center positions of each substrate and film. The concentric moiré fringe marks include 360 radial grating lines with an included angle of 1 degree, an inner diameter R1 = 10 mm, an outer diameter R2 = 12 mm, and an angular positioning accuracy of the spoke-shaped grating lines of ±0.001 degrees. The concentric moiré fringe marks are used to detect rotational deviation Δθ.

4. The high-precision alignment method for coated iron according to claim 3, characterized in that: The resolution of the linear array camera is 12K and the scanning frequency is 10kHz. A two-dimensional Fourier transform is applied to the collected image data of the line grid moiré fringe mark to obtain the fundamental frequency signal of the moiré fringe. The formula is: Wherein, F(u, v) is the fundamental frequency signal of the image data of the line grid moiré fringe mark, f(x, y) is the time domain image of the image data of the line grid moiré fringe mark, u and v are frequency variables, x and y represent the horizontal and vertical coordinates of each pixel in the image data of the line grid moiré fringe mark, f(x, y) is the image function of the image data of the line grid moiré fringe mark, which represents the grayscale value of the pixel at the plane coordinate (x, y), (u, v) is the frequency domain coordinate, which represents different frequency components, u represents the frequency in the horizontal direction, v represents the frequency in the vertical direction, F(u, v) is the image function in the frequency domain, which represents the frequency component at the frequency coordinate (u, v), and j is an imaginary number; The fundamental frequency signal is correlated and the phase difference of the line grid moiré fringe mark between the film and the substrate is generated based on the following formula: in, is the lateral phase deviation, is the longitudinal phase deviation, arg(F x )、arg(F y ) represent the phase information of the horizontal and vertical Fourier transform results respectively, where Correlation analysis is performed on the phase difference to generate the lateral deviation ΔX and longitudinal deviation ΔY based on the following formula: The lateral deviation ΔX is used to reflect the lateral deviation distance of the wire grid moiré fringe marks on the substrate and the film, and the longitudinal deviation ΔY is used to reflect the longitudinal deviation distance of the wire grid moiré fringe marks on the substrate and the film.

5. The high-precision alignment method for coated iron according to claim 1, characterized in that: The resolution of the area array camera is 16MP. Hough transform is applied to the collected concentric circle moiré fringe mark image data to identify the circular edge and obtain the coordinates of the circle center and the concentric circle moiré fringe mark line grid angle θ.

6. The high-precision alignment method for coated iron according to claim 5, characterized in that: Correlation analysis of the wire grid angle θ is performed to generate the rotation deviation Δθ based on the formula: Wherein, the wire grid angle θ is the difference between the angle of the spoke-shaped wire grid of the concentric moiré fringe marking on the film and the angle of the spoke-shaped wire grid of the concentric moiré fringe marking on the substrate, N is the total number of spoke-shaped wire grids of the concentric moiré fringe marking wire grid, and ΔN is the number of wire grids that produce phase difference in the spoke-shaped wire grid of the concentric moiré fringe marking.

7. A high-precision alignment method for coated iron according to any one of claims 4 or 6, characterized in that: The correlation analysis of the concentric moiré fringe marker line grid angle θ, rotation deviation Δθ, lateral deviation and longitudinal deviation is performed to generate the deviation coupling matrix based on the formula: Where R is the radius of the concentric moiré fringe marker, ΔX′ is the lateral offset of the coating, ΔY′ is the longitudinal offset of the coating, and Δθ′ is the deflection of the coating, with the unit being degrees.

8. The high-precision alignment method for coated iron according to claim 7, characterized in that: An air-floating guide rail and a voice coil motor are used to drive the film translation. The film position is adjusted according to ΔX′ and ΔY′ until the wire grid moiré marks on the film coincide with the wire grid moiré marks on the substrate. The film angle is adjusted by a magnetic levitation rotary table with an adjustment amount of Δθ′. During the adjustment process, the contrast between the wire grid and the spoke-mounted wire grid is fed back in real time. When the contrast is greater than or equal to 90% and the center coordinate deviation is less than 0.02μm, the alignment is considered complete.

9. A high-precision alignment device for coated iron, used to perform the high-precision alignment method for coated iron according to claim 1, characterized in that: include: Marking module, used to add wire grid moiré fringe marks to the film and substrate during the coated iron process, and to add concentric circle moiré fringe marks to the film and substrate; The wire grid analysis module is used to completely capture the wire grid moiré fringe marks through a linear array camera, continuously collect image data of the wire grid moiré fringe marks, obtain the fundamental frequency signal of the moiré fringe through Fourier transform, perform correlation analysis on the fundamental frequency signal, generate the phase difference of the wire grid moiré fringe marks between the film and the substrate, perform correlation analysis on the phase difference, and generate lateral deviation and longitudinal deviation; The circular grating analysis module is used to collect concentric circular moiré fringe mark image data through an area array camera, fit the concentric circular moiré fringe mark center coordinates and the line grating angle θ through Hough transform, and further analyze and generate a rotation deviation Δθ. The line grating angle θ is the angle of the spoke-shaped line grating of the fitted concentric circular moiré fringe mark; Deviation coupling module, used to perform correlation analysis on the angle θ, rotation deviation Δθ, lateral deviation and longitudinal deviation of the concentric moiré fringe marker grid to generate a deviation coupling matrix; Adjustment module, used for translation and rotation adjustment of lamination position.

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