Positioning compensation method for display panel camera

Abstract

The present invention provides a positioning compensation method for a display panel camera, comprising: measuring the straightness and linearity of the X-axis and Y-axis, as well as the perpendicularity between the X-axis and Y-axis; wherein the X-axis is the extension direction of a display panel clamping mechanism, and the Y-axis is the extension direction of a camera, which is mounted across the clamping mechanism and is used to photograph the display panel; performing a linear combination of the straightness and linearity of the X-axis and Y-axis, as well as the perpendicularity between the X-axis and Y-axis, and then compensating and correcting the X-axis and Y-axis to compensate for the camera's positioning. A microscope is mounted on the camera, and the camera can move back and forth along a slide rail along the X-axis, while the microscope can move back and forth along the slide rail along the Y-axis. The present invention employs a method of deviation testing and corresponding compensation to address the problem of inaccurate positioning. Testing and verification have shown that this method significantly improves axis positioning accuracy, ensuring that system error meets design requirements and exhibits good stability.

Description

Technical Field

[0001] The present invention relates to the technical field of display panels, and in particular to a positioning compensation method for a display panel camera. Background Art

[0002] With the development of the display panel industry, integrated circuit manufacturing processes are constantly improving, and precision requirements are becoming increasingly stringent. To identify process issues, after detecting areas of interest such as defects, particles, and feature points, a camera is used to capture clearer images at designated locations. However, due to a combination of factors such as hardware manufacturing errors, assembly errors, component thermal reactions, and control compensation errors, achieving higher precision motion requirements may be impossible, or system errors may exceed standards. In even worse cases, the area of ​​interest may shift from the center of the microscope's field of view when the camera reaches the designated location, or the area of ​​interest may be lost when switching to a higher-magnification lens. In such situations, despite improvements to the hardware's inherent process and assembly accuracy, the combined effects of these factors still lead to certain system errors.

[0003] By controlling the camera's microscope to move to a designated position and zooming in on the area of ​​interest, you can obtain more detailed images. However, due to interference from hardware, software, and the environment, some deviations may occur in the combined superposition, leading to the following problems:

[0004] (1) There is a certain deviation between the actual movement position of the microscope and the theoretical one;

[0005] (2) The defect is not in the center of the image when it is photographed (or the deviation is large);

[0006] (3) When switching to a higher magnification, the region of interest is not in the field of view;

[0007] (4) The system error does not meet the standard.

[0008] The above problems can be summarized as inaccurate positioning, which brings troubles in use and cannot achieve higher-precision motion effects.

[0009] The existing technologies generally include: (1) using CCD to collect regularly arranged Marks, perform template matching, record the deviations of X and Y, and use this data to compensate the axis; this method is relatively general and cannot analyze the source of the error, and the resolution is relatively low; (2) installing a laser interferometer structure to adjust the motion state of the axis through real-time feedback of the moving distance; this method has high precision and strong reliability, but high cost, complex structure, and high requirements for the use environment. Considering applicability, it is not the best choice.

[0010] Existing compensation methods have the following shortcomings when facing practical engineering problems:

[0011] 1. Applications in different fields have significant differences in structure, environment, cost, and application scenarios, making direct reference impossible.

[0012] 2. Positioning accuracy is a comprehensive issue. Using general testing methods cannot troubleshoot system problems.

[0013] 3. The source of positioning deviation is unclear, and it is impossible to pinpoint the problem and provide a clear solution.

[0014] 4. Use the matching MARK mark method to determine the offset. The arrangement and number of MARK marks on the display panel are relatively limited, the resolution is not high enough, and the calculation method is relatively complicated. Summary of the Invention

[0015] The purpose of the present invention is to solve the problem of inaccurate positioning by adopting a method of deviation testing and corresponding compensation.

[0016] The key points of the present invention are: (1) using a method of measuring the position offset of a straight line edge to calculate the deviation;

[0017] (2) Comprehensive problems are decomposed into linearity, straightness, and perpendicularity; (3) Independent tests can help engineers troubleshoot system problems; (4) By utilizing the characteristics of linear systems, the method of superimposing and integrating system errors can achieve accurate positioning compensation.

[0018] Specifically, the present invention provides a positioning compensation method for a display panel camera, comprising:

[0019] Measure the straightness and linearity of the X-axis and Y-axis, as well as the perpendicularity between the X-axis and Y-axis; wherein the X-axis is the extension direction of the display panel clamping mechanism, and the Y-axis is the extension direction of the camera, which is installed across both sides of the clamping mechanism and is used to take pictures of the display panel;

[0020] The straightness and linearity of the X-axis and Y-axis, as well as the perpendicularity between the X-axis and Y-axis are linearly combined, and then the X-axis and Y-axis are compensated and corrected to perform positioning compensation for the camera.

[0021] Furthermore, the microscope is mounted on the camera, the camera can move back and forth along the slide rail on the X axis, and the microscope can move back and forth along the slide rail in the Y axis direction.

[0022] Furthermore, in the measurement, pattern glass is used as a measuring tool, and the interior of the pattern glass has standard horizontal and vertical straight lines and a regular panel distribution.

[0023] The advantage of this invention is that it uses a method of deviation testing and corresponding compensation to solve the problem of inaccurate positioning. Through testing and verification, this method can significantly improve the accuracy of shaft positioning, making the system error meet the design requirements and have good stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0025] Figure 1 A schematic diagram of the hardware structure involved in the positioning compensation method of a display panel camera according to an embodiment of the present invention is shown.

[0026] Figure 2 A schematic diagram of a motion platform and panel model according to an embodiment of the present invention is shown.

[0027] Figure 3 A schematic diagram of the linearity measurement process of the X-axis and the Y-axis according to an embodiment of the present invention is shown.

[0028] Figure 4 A schematic diagram of the linearity measurement process of the X-axis and the Y-axis according to an embodiment of the present invention is shown.

[0029] Figure 5 A schematic diagram of a process for measuring the perpendicularity between the X-axis and the Y-axis according to an embodiment of the present invention is shown.

[0030] Figure 6 FIG. 4 shows a principle diagram of a method for calculating a compensation value in the X direction according to an embodiment of the present invention.

[0031] Figure 7 A principle diagram of a method for calculating a compensation value in the Y direction according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0032] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0033] Figure 1 FIG. 1 shows a schematic diagram of the hardware structure involved in the positioning compensation method of the display panel camera according to an embodiment of the present invention. Figure 1As shown, the device includes a microscope, a clamping mechanism, an X-axis, a Y-axis, a glass panel, and a camera. The X-axis is the extension direction of the display panel clamping mechanism, and the Y-axis is the extension direction of the camera. The camera spans both sides of the clamping mechanism and is used to photograph the display panel. The microscope is mounted on the camera. The camera can move back and forth along the X-axis along the slide rail, and the microscope can move back and forth along the Y-axis along the slide rail.

[0034] The straightness and linearity of the X-axis and Y-axis, as well as the perpendicularity between the X-axis and Y-axis are linearly combined, and then the X-axis and Y-axis are compensated and corrected to perform positioning compensation for the camera.

[0035] The two-dimensional position of a camera machine is determined by the X and Y axes. Each axis is controlled and moved independently, and the accuracy of positioning is directly related to these two axes. To improve positioning accuracy and better troubleshoot problems, this method proposes an offline axis deviation measurement and corresponding compensation method to solve this problem. Each axis is independent and therefore requires independent compensation. This method measures the straightness, linearity, and X and Y perpendicularity of each axis, linearly combines these three parameters, and then compensates and corrects each axis to achieve precise positioning.

[0036] In the present invention, the parameter test of the axis needs to use the pattern process glass as a measuring tool. The pattern has horizontal and vertical straight line standard processes inside, with regular panel distribution, running through the entire glass, the motion platform and panel model are as follows: Figure 2 shown.

[0037] This method uses a two-dimensional matrix point map to move the microscope to the specified point, use the microscope to collect images, calculate the X / Y direction edge position of the marked straight line, calculate and record the position X0 / Y0 at the starting point, and do the same operation at other points, and collect images in turn to calculate and record the straight line edge position X n \Y n , the deviation between other points and the starting point:

[0038] The X direction is: E = X n -X0

[0039] The Y direction is: E = Y n -Y0

[0040] Based on the above deviation calculation method, the following axis offset performance measurement is completed. The compensation accuracy can be controlled by changing the density of the two-dimensional matrix.

[0041] The clamping mechanism adjusts the panel glass's posture so that the pattern glass is essentially parallel to the X-axis. The following offline measurement, online calculation, and compensation are performed. The specific methods and steps are as follows:

[0042] 1.X, Y axis linearity measurement

[0043] 1) X-axis straightness X_DY measurement

[0044] Find the straight line process in the X direction of the Pattern glass near the head position of X=0, move the X axis (dot matrix) in the positive direction at equal intervals, and the Y direction position Y0 of the straight line edge in the microscope field of view at the starting position X0 and the current X n Position Y of the straight edge in the microscope n The difference is X_DY. Record each X position and the corresponding DY until the end, throughout the X direction of the glass.

[0045] The corresponding DY at the X position is: n _DY=Y n -Y0.

[0046] 2) Y-axis straightness Y_DX measurement

[0047] Find the straight line process in the Y direction of the pattern glass near the Y=0 head position, move the Y axis (dot matrix) in the positive direction at equal intervals, and the X direction position X0 of the straight line edge in the microscope field of view at the starting Y0 position and the current Y n Position X direction position of the straight edge in the microscope n The difference is Y_DX. Record each Y position and the corresponding DX until the end, throughout the Y direction of the glass.

[0048] The corresponding DX at the Y position is: Y n _DX=X n -X0.

[0049] Figure 3 A schematic diagram of the linearity measurement process of the X-axis and the Y-axis according to an embodiment of the present invention is shown.

[0050] 2. X and Y axis linear measurement

[0051] 1) X-axis linearity X_DX measurement

[0052] Starting from the first panel in the pattern glass near the head position X=0, move the X axis (dot matrix) in the positive direction at equal intervals. The X direction position X0 of the straight edge in the microscope field of view at the starting position X0 and the current X n Position X direction position of the straight edge in the microscope n The difference is X_DX. Record each X position and the corresponding DX until the end, throughout the X direction of the glass.

[0053] The corresponding DX under X position is: X n _DX=X n -X0.

[0054] 2) Y-axis linearity Y_DY measurement

[0055] Starting from the first panel in the pattern glass near the Y=0 head position, move the Y axis (dot matrix) in the positive direction at equal intervals. The Y direction position Y0 of the straight edge in the microscope field of view at the starting Y0 position and the current Y n Position Y of the straight edge in the microscope n The difference is Y_DY. Record each Y position and the corresponding DY until the end, throughout the Y direction of the glass.

[0056] The corresponding DY at the Y position is: n _DY=Y n -Y0.

[0057] Figure 4 A schematic diagram of the linearity measurement process of the X-axis and the Y-axis according to an embodiment of the present invention is shown.

[0058] 3. X and Y axis vertical measurement

[0059] Using the X-axis as the reference axis, theoretically, Y-axis movement should be perpendicular to the X-axis. However, in practice, there are angles that are not equal to 90°. Each X-axis position has an angle with the Y-axis. If the two are not perpendicular, compensation is applied at that position (or the position between two measurement points), so perpendicularity testing is required for each subdivided position. A horizontal straight line on the glass plate that can penetrate the Y-axis travel is found. The offset of the horizontal line edge at the first (x1, y1) and last (x2, y2) positions in the microscope field of view is calculated, and the vertical parameters are then calculated based on trigonometric functions.

[0060] Figure 5 A schematic diagram of the vertical measurement process between the X-axis and the Y-axis according to an embodiment of the present invention is shown. Figure 5 For the model, the relationship between the actual and theoretical perpendicularity of the X and Y axes can be expressed by the formula: Tan(θ)=(y2-y1) / (x2-x1).

[0061] In different Y n In the axis coordinate, it will correspond to X n There is a deviation value in the axis direction, namely: Δx n =y n *Tan(θ) n .

[0062] 4. Deviation Performance Linear Combination

[0063] In this system, the axis deviation is mainly composed of the three components of straightness, linearity, and perpendicularity mentioned above. They are independent of each other and can be superimposed, which conforms to the characteristics of a linear system. Therefore, the deviation composition can be expressed by the formula:

[0064] ΔE(n)=ΔE1(n)+ΔE2(n)+ΔE3(n)

[0065] ΔE1(n) is the linearity deviation, ΔE2(n) is the straightness deviation, and ΔE3(n) is the perpendicularity deviation.

[0066] 1) If Figure 6 As shown, the compensation value in the X direction is: ΔE X (n)=(X n -DX)+(Y n -DX)+y t *Tan(θ) n

[0067] Where: ΔE1(n)=X n -DX; ΔE2(n)=Y n -DX; ΔE3(n)=y t *Tan(θ) n

[0068] 2) If Figure 7 As shown, the compensation value in the Y direction is: ΔE Y (n)=(Y n -DY)+(X n -DY)

[0069] Where: ΔE1(n)=Y n -DY; ΔE2(n)=X n -DY; ΔE3(n)=0

[0070] 5. Online compensation of 2D motion

[0071] 1) Save the above measured data in a document;

[0072] 2) Target value of machine coordinates (X tx ,Y ty ), by calling the document, find X tx 、Y ty Front and back (left and right) adjacent coordinates (X tx-1 ,Y ty-1 ) and (X tx+1 ,Y ty+1 ), and the corresponding deviation values ​​under each factor can be found (EX tx-1 ,EY ty-1 ) and (EX tx+1 ,EY ty+1 );

[0073] 3) When measuring performance, there is a certain subdivision (matrix density). The linear interpolation method is used to supplement the two corresponding deviation values ​​​​before and after (left and right) to obtain the specific compensation value under this value.

[0074] Calculate the X-direction compensation value by linear interpolation method:

[0075] EX tx =(X tx -X tx-1 )*(EX tx+1 -EX tx-1 ) / (X tx+1 -X tx-1 )

[0076] Calculate the Y direction compensation value by linear interpolation method:

[0077] EY ty =(Y ty -Y ty-1 )*(EY ty+1 -EY ty-1 ) / (Y ty+1 -Y ty-1 )

[0078] 4) Superimpose the three deviations and add them to the target value, and the actual moving position (X a ,Y a ) is the target position after the deviation is superimposed.

[0079] The deviation after superposition is EX tx , after compensation in X direction:

[0080] X a =X tx +EX tx

[0081] The deviation after superposition is EY ty , after Y direction compensation:

[0082] Y a =Y ty +EY ty

[0083] The foregoing description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be readily conceived by a person skilled in the art within the technical scope disclosed herein are intended to be encompassed within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A positioning compensation method for a display panel camera, characterized in that: include: Measuring the straightness and linearity of the camera's X-axis and Y-axis, as well as the perpendicularity between the X-axis and Y-axis; wherein the X-axis is the extension direction of the display panel clamping mechanism, and the Y-axis is the extension direction of the camera, which is installed across both sides of the clamping mechanism to take pictures of the display panel; The microscope is mounted on the camera, the camera can move back and forth along the slide rail on the X axis, and the microscope can move back and forth along the slide rail on the Y axis; In the measurement, pattern glass is used as a measuring tool. The interior of the pattern glass has a standard process of horizontal and vertical straight lines and a regular panel distribution; The measuring of the straightness of the X-axis and the Y-axis includes: 1) X-axis straightness X_DY measurement Find the straight line process in the X direction of the Pattern glass near the head position of X=0, move the X axis in the positive direction at equal intervals, and compare the Y direction position Y0 of the straight line edge in the microscope field of view at the starting X0 position with the current X n Position Y of the straight edge in the microscope n The difference is recorded as X_DY; record each X position and the corresponding DY until the end, through the pattern glass X direction, where the corresponding DY at the X position is: X n _DY=Y n -Y0; 2) Y-axis straightness Y_DX measurement The Y-axis straightness Y_DX measurement is performed using the same operation as the X-axis straightness X_DY measurement; The linearity measurement of the X-axis and Y-axis includes: 1) X-axis linearity X_DX measurement Starting from the first panel in the pattern glass near the head position X=0, move the X axis in the positive direction at equal intervals, and compare the X direction position X0 of the straight edge in the microscope field of view at the starting X0 position with the current X n Position X direction position of the straight edge in the microscope n The difference is recorded as X_DX; record each X position and the corresponding DX until the tail, through the glass X direction; where the corresponding DX at the X position is: X n _DX=X n -X0; 2) Y-axis linearity Y_DY measurement The Y-axis linearity Y_DY measurement is performed using the same operation as the X-axis linearity X_DX measurement. Measuring the perpendicularity between the X-axis and the Y-axis includes: Find the horizontal straight line on the glass plate that can penetrate the Y-axis travel, calculate the offset of the horizontal straight line edge at the first and last positions on the microscope field of view, and then calculate the perpendicularity based on the trigonometric function relationship; The deviation of the straightness of the X-axis and the Y-axis, the deviation of the linearity, and the deviation of the perpendicularity between the X-axis and the Y-axis are linearly combined, and then the X-axis and the Y-axis are compensated and corrected to perform positioning compensation for the camera.

2. The positioning compensation method for a display panel camera according to claim 1, wherein: The linear combination of the deviation of the straightness of the X-axis and the Y-axis, the deviation of the linearity, and the deviation of the perpendicularity between the X-axis and the Y-axis comprises: The deviation components of the X-axis and Y-axis are expressed by the formula: ΔE(n)=ΔE1(n)+ΔE2(n)+ΔE3(n) ΔE1(n) is the linearity deviation, ΔE2(n) is the straightness deviation, and ΔE3(n) is the perpendicularity deviation.

3. The positioning compensation method for a display panel camera according to claim 2, wherein: The compensation and correction of the X-axis and the Y-axis to perform positioning compensation of the camera includes: 1) Save the above measured data in a document; 2) Target value of the camera's platform coordinates (X tx ,Y ty ), by calling the document, find X tx 、Y ty The adjacent coordinates (X tx-1 ,Y ty-1 ) and (X tx+1 ,Y ty+1 ), and find the corresponding deviation value of the adjacent coordinates before and after (EX tx-1 ,EY ty-1 ) and (EX tx+1 ,EY ty+1 ); 3) Using the linear interpolation method to compensate for the corresponding deviation values ​​of the adjacent coordinates, a specific compensation value under the deviation value is obtained; 4) Superimpose the three deviations and add them to the target value to obtain the actual moving position.

4. The positioning compensation method for a display panel camera according to claim 3, wherein: The specific compensation value is calculated as follows: Calculate the X-direction compensation value by linear interpolation method: EX tx =(X tx -X tx-1 )*(EX tx+1 -EX tx-1 ) / (X tx+1 -X tx-1 ) Calculate the Y direction compensation value by linear interpolation method: HEY ty =(And ty -AND ty-1 )*(HEY ty+1 -HEY ty-1 ) / (AND ty+1 -AND ty-1 )。 5. The positioning compensation method for a display panel camera according to claim 4, wherein: The actual moving position is calculated as follows: The deviation after superposition is EX tx , after compensation in X direction: X a =X tx +EX tx The deviation after superposition is EY ty , after Y direction compensation: AND a =And ty +EY ty 。

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