Alignment method of LDI exposure machine and LDI exposure machine

Abstract

The invention discloses an alignment method of an LDI exposure machine and the LDI exposure machine, the LDI exposure machine comprises a motion platform for pulling a substrate to move and a plurality of alignment cameras, the plurality of alignment cameras are linearly arranged along the width direction of the substrate, the motion platform is located below the plurality of alignment cameras, and the alignment method comprises the following steps: acquiring GDS drawing information about a positioning point; determining an optimal acquisition path corresponding to each alignment camera according to the GDS drawing information; controlling each alignment camera according to the optimal acquisition path corresponding to each alignment camera; controlling the motion platform to move back and forth between the starting point of the substrate and the end point of the substrate until the alignment camera completes image acquisition of all the positioning points; determining positioning point image information of each positioning point according to all the image information; and performing alignment according to the positioning point image information of each positioning point. By adopting the alignment method, the alignment speed of the LDI exposure machine can be improved to the greatest extent when the number of the positioning point partitions on the substrate is large, and the problem of camera redundancy is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of LDI exposure, and in particular to an alignment method of an LDI exposure machine and an LDI exposure machine. Background Art

[0002] In the related art, the existing LDI (laser direct imaging) exposure machine searches for the position of each positioning point in turn through the line spacing, controls the mutual vector movement of the camera and the motion platform, so that the camera stops shooting the positioning point image after reaching above each positioning point, and then performs alignment through the positioning point image of each positioning point. However, this method can only align the positioning points one by one during the alignment process, so there is a problem of slow alignment speed when there are many positioning point partitions on the substrate, thereby reducing the production capacity of the exposure machine. In addition, when multiple cameras are set to collect positioning point images for alignment, only one camera can collect images at the same time, which causes the problem of camera redundancy. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present invention is to propose a positioning method for an LDI exposure machine, which can maximize the positioning speed of the LDI exposure machine when there are many positioning point partitions on the substrate and avoid the problem of camera redundancy.

[0004] A second objective of the present invention is to provide an LDI exposure machine.

[0005] In order to solve the above problems, a first aspect of the present invention provides an alignment method for an LDI exposure machine, wherein the LDI exposure machine includes a motion platform for pulling a substrate to move and a plurality of alignment cameras, wherein the plurality of alignment cameras are arranged in a line along the width direction of the substrate, and the motion platform is located below the plurality of alignment cameras. The alignment method includes: acquiring GDS drawing information about positioning points; determining an optimal acquisition path corresponding to each alignment camera according to the GDS drawing information; controlling each alignment camera according to the optimal acquisition path corresponding to each alignment camera; controlling the motion platform to move back and forth between the starting point and the end point of the substrate until the alignment camera completes image acquisition of all positioning points, wherein an image acquisition signal is triggered every time it is determined that the real-time moving distance of the motion platform reaches a shooting interval distance, and the image acquisition signal is used to instruct the plurality of alignment cameras to synchronously acquire image information; determining the positioning point image information of each positioning point according to all the image information; and performing alignment according to the positioning point image information of each positioning point.

[0006] According to the alignment method of the LDI exposure machine of the embodiment of the present invention, each alignment camera is driven to move according to the corresponding optimal acquisition path, and then the motion platform is driven to move back and forth between the starting point and the end point of the substrate, and each time the motion platform moves to the shooting interval distance, it triggers multiple alignment cameras to shoot images, so as to obtain all image information at one time, and then filter and obtain the positioning point image information of each positioning point for positioning. Therefore, compared with the existing LDI exposure machine that aligns each positioning point one by one through the mutual vector movement of the control machine and the motion platform, in the present application, after all the positioning point image information is obtained at one time, the positioning point image information of each positioning point can be obtained after filtering and then positioning is performed through the positioning image information of each positioning point, instead of obtaining each positioning point image one by one and then positioning, but by controlling the motion platform to move along the length direction of the substrate and controlling the camera to move along the width direction of the substrate, the alignment speed of the LDI exposure machine can be maximized. In addition, multiple alignment cameras can synchronously shoot images at the same time, thereby avoiding the problem of camera redundancy.

[0007] In some embodiments, determining the optimal acquisition path corresponding to each alignment camera according to the GDS drawing information includes: rasterizing the GDS drawing information to obtain row-column relationship results of all positioning points and GDS coordinate information of each positioning point; determining the alignment camera corresponding to each column of positioning points in the row-column relationship results; performing path planning according to the GDS coordinate information of the first positioning point in each column in the row-column relationship results corresponding to each alignment camera to obtain the optimal acquisition path corresponding to each alignment camera, wherein the first positioning point in each column is a positioning point on the substrate close to the starting point of the substrate.

[0008] In some embodiments, determining the alignment camera corresponding to each column of the positioning point in the row-column relationship result includes: obtaining the acquisition area boundary of each alignment camera; and determining the alignment camera corresponding to each column of the positioning point in the row-column relationship result based on the GDS coordinate information of the first positioning point in each column in the row-column relationship result and the acquisition area boundary of each alignment camera.

[0009] In some embodiments, path planning is performed based on the GDS coordinate information of the first positioning point in each column in the row-column relationship result corresponding to each aiming camera to obtain the optimal acquisition path corresponding to each aiming camera, including: obtaining a pathfinder corresponding to each aiming camera; determining the starting position information of each pathfinder based on the GDS coordinate information of the first positioning point in each column; determining the acquisition path corresponding to each aiming camera based on the starting position information of each pathfinder and the GDS coordinate information of the first positioning point in each column, and adding the acquisition path to the set of alternative paths corresponding to each aiming camera until the number of acquisition paths in the set of alternative paths corresponding to each aiming camera reaches a preset number; determining the shortest acquisition path in the set of alternative paths corresponding to each aiming camera; and using the shortest acquisition path in the set of alternative paths corresponding to each aiming camera as the optimal acquisition path corresponding to each aiming camera.

[0010] In some embodiments, a limit switch is provided at the end point of the motion platform to control the motion platform to move back and forth between the starting point and the end point of the substrate, including: when it is determined that the alignment camera is located above the first positioning point in each column of the optimal acquisition path, the motion platform is controlled to move forward along the length direction of the substrate; when it is determined that the motion platform triggers the limit signal of the limit switch, the motion platform is controlled to move reversely along the length direction of the substrate.

[0011] In some embodiments, the positioning point image information of each positioning point is determined based on all the image information, including: obtaining the GDS coordinate mapping relationship about the positioning point, and obtaining the acquired image size information of the alignment camera; and filtering out the positioning point image information of each positioning point in all the image information based on the GDS coordinate mapping relationship and the acquired image size information.

[0012] In some embodiments, the alignment method also includes: determining an initial recognition position of each positioning point in the corresponding positioning point image information; determining a mapping relationship function between the positioning point image information about the same positioning point collected by each adjacent two alignment cameras among multiple alignment cameras; determining a final recognition position of each positioning point in the corresponding positioning point image information based on the mapping relationship function and the initial recognition position; and determining a substrate position recognition result of each positioning point based on the final recognition position of each positioning point.

[0013] In some embodiments, a mapping relationship function between image information about the same positioning point collected by each adjacent two alignment cameras among a plurality of alignment cameras is determined, including: for the positioning point image information collected by each alignment camera, determining the image coordinate information of each positioning point in the corresponding positioning point image information; and determining the mapping relationship function between the image information about the same positioning point collected by each adjacent two alignment cameras based on the image coordinate information of each positioning point.

[0014] In some embodiments, the substrate position recognition result of each positioning point is determined according to the final recognition position of each positioning point, including: determining the mapping relationship between the image coordinate information about the positioning point and the substrate coordinate information; performing position conversion on the final recognition position of each positioning point according to the mapping relationship to determine the substrate position recognition result of each positioning point.

[0015] A second aspect of the present invention provides an LDI exposure machine, comprising: a plurality of alignment cameras, the plurality of alignment cameras are arranged in a line along the width direction of the substrate, each alignment camera is used to acquire image information of a positioning point on the substrate in response to an image acquisition signal; a motion platform, the motion platform is located below the plurality of alignment cameras, the motion platform is used to pull the substrate to move; a controller, the controller is connected to the motion platform and the plurality of alignment cameras, and is used to execute the alignment method of the LDI exposure machine described in the above embodiment.

[0016] According to the LDI exposure machine of the embodiment of the present invention, by executing the alignment method of the LDI exposure machine of the above embodiment, the alignment speed of the LDI exposure machine can be maximized when there are many positioning point partitions on the substrate, avoiding the problem of camera redundancy.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 is a schematic diagram of an LDI exposure machine according to an embodiment of the present invention; Figure 2 is a flow chart of an alignment method of an LDI exposure machine according to an embodiment of the present invention; Figure 3 is a flow chart of acquisition path planning according to one embodiment of the present invention; FIG4( a ) is a schematic diagram of the motion direction of a motion platform according to an embodiment of the present invention; FIG4( b ) is a schematic diagram of the motion direction of the motion platform according to another embodiment of the present invention; Figure 5 is a flow chart of an alignment method of an LDI exposure machine according to another embodiment of the present invention.

[0019] Reference numerals: Host computer 1; controller 2; axis driver 3; PSO board 4; light source 5; memory module 6; alignment camera 7; substrate 8. DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0021] In order to solve the above problems, a first embodiment of the present invention provides an alignment method for an LDI exposure machine. The alignment method can maximize the alignment speed of the LDI exposure machine when there are many positioning point partitions on the substrate, thereby avoiding the problem of camera redundancy.

[0022] In an embodiment, the LDI exposure machine may be a high-end exposure machine, such as Figure 1 As shown, the LDI exposure machine 10 includes a motion platform (not shown in the figure) for pulling the substrate 8 to move and a plurality of alignment cameras 7. The alignment cameras 7 may be CCD (charge coupled device camera) cameras. The motion platform pulls the substrate 8 to move along the length direction Y of the substrate. The plurality of alignment cameras 7 are arranged in a line along the width direction X of the substrate, and the motion platform is located below the plurality of alignment cameras 7. In addition, the LDI exposure machine 10 also includes a host computer 1, a controller 2, an axis driver 3, a PSO (position synchronized output) board 4, a light source 5, and a memory module 6. Specifically, the host computer 1 is used to send control instructions to the controller 2 and process image acquisition signals, etc.; the controller 2 pulls the motion platform to move by controlling the axis driver 3; the axis driver 3 is used to drive the motion platform 8 to move, the PSO board 4 is connected to the controller 2 and each alignment camera 7, and is used to split the image acquisition signal sent by the controller 2 into multiple image acquisition sub-signals, and send each image acquisition sub-signal to each alignment camera 7; the light source 5 is located below the multiple alignment cameras 7, and the light source 5 is connected to the PSO board 4, and is used to flash according to the image acquisition signal; the memory module 6 is used to store the image information acquired by the alignment camera 7.

[0023] Specifically, the PSO board is used to receive the image acquisition signal sent by the controller, and split the image acquisition signal sent by the controller into multiple image acquisition sub-signals accordingly, and send the multiple image acquisition sub-signals to each alignment camera, and each alignment camera performs image acquisition after receiving the image acquisition sub-signals.

[0024] Reference below Figure 2 The alignment method of the LDI exposure machine according to the embodiment of the present invention is described as follows: Figure 2 As shown, the method includes steps S1 to S6.

[0025] Step S1, obtaining GDS (Geodetic Coordinate System, ground coordinate system) drawing information about the positioning point.

[0026] Among them, the GDS drawing is a drawing about the location of the positioning points on the substrate.

[0027] Specifically, the user inputs the GDS drawing into the host computer, and the host computer obtains the GDS drawing information about the positioning point.

[0028] Step S2, determining the optimal acquisition path corresponding to each alignment camera according to the GDS drawing information.

[0029] The optimal acquisition path corresponding to each alignment camera refers to the shortest distance trajectory that the alignment camera needs to move when completing the multi-partition alignment task. In addition, the optimal acquisition path can also be called the "flying path", which is the path that takes the least time for the alignment camera and the motion platform. The optimal acquisition path ensures that the alignment camera can efficiently cover all positioning points within the minimum displacement range, thereby minimizing movement time and mechanical loss and improving overall alignment efficiency.

[0030] Specifically, all the positioning points on the substrate in the present application are regularly distributed, and multiple alignment cameras are arranged in a line along the width direction of the substrate, that is, the field of view of the multiple alignment cameras corresponds to a continuous area on the substrate in the width direction, and the distances between the multiple alignment cameras and the positioning points in the width direction of the substrate are different. Therefore, in order to ensure that the multiple alignment cameras can quickly capture part of the positioning points in the width direction of the substrate, the multiple positioning points in the width direction of the substrate are assigned to each alignment camera, and path planning is performed for the positioning points assigned to each alignment camera. In other words, since the GDS drawing information contains the design position information of the positioning points on the substrate, the path planning can be performed for the positioning points assigned to each alignment camera according to the GDS drawing information to obtain the optimal acquisition path corresponding to each alignment camera, wherein the optimal acquisition path can be understood as the path with the least movement and the shortest movement time when the alignment camera captures the images corresponding to the assigned multiple positioning points.

[0031] Step S3, controlling each alignment camera according to the optimal acquisition path corresponding to each alignment camera.

[0032] Specifically, the optimal acquisition path can be the moving order or moving path of the positioning points assigned to each alignment camera. Each alignment camera is controlled to move above each assigned positioning point in the corresponding optimal acquisition path according to the optimal acquisition path corresponding to each alignment camera, so as to shorten the multi-partition alignment path distance, enable each alignment camera to quickly capture the substrate image, and improve the alignment speed of the exposure machine.

[0033] Step S4, controlling the motion platform to move back and forth between the starting point and the end point of the substrate until the alignment camera completes image acquisition of all positioning points, wherein an image acquisition signal is triggered every time the real-time moving distance of the motion platform reaches the shooting interval distance, and the image acquisition signal is used to instruct multiple alignment cameras to synchronously acquire image information.

[0034] The shooting interval distance can be understood as the distance between two adjacent images taken by the aiming camera. The shooting interval distance is determined by the shooting field of view of the aiming camera. The shooting interval distance can be 3.5um, and the size of the picture taken by the aiming camera is 2064×1544.

[0035] Specifically, since all the positioning points on the substrate in the present application are regularly distributed, after controlling each alignment camera to move above each assigned positioning point in the corresponding optimal acquisition path, in order to obtain all images in the length direction of the substrate corresponding to each assigned positioning point, the motion platform is controlled to move back and forth between the starting point of the substrate and the end point of the substrate, and in the process of the motion platform moving from the starting point of the substrate to the end point of the substrate, since the shooting field of view of the alignment camera for the substrate is fixed, the shooting interval distance is set according to the shooting field of view of the alignment camera, and all the positioning points on the substrate are divided into multiple substrate shooting areas in the length direction of the substrate according to the shooting interval distance. When the real-time moving distance of the motion platform reaches the shooting interval distance, the motion platform loads the substrate and moves to the unphotographed substrate shooting area, and then triggers an image acquisition signal, so that each alignment camera synchronously collects image information in the substrate shooting area until the motion platform moves to the end point of the substrate. At this time, it means that each alignment camera has collected all images in the length direction of the substrate corresponding to each assigned positioning point, and then the motion platform is controlled to return from the end point of the substrate to the starting point of the substrate until all images in the length direction of the substrate corresponding to the positioning point assigned by each alignment camera are obtained. Therefore, in the present application, the motion platform is controlled to move back and forth between the starting point and the end point of the substrate to capture the positioning point image, so as to shorten the multi-zone alignment path distance, so that each alignment camera can quickly capture the substrate image and improve the alignment speed of the exposure machine.

[0036] Step S5, determining the positioning point image information of each positioning point according to all the image information.

[0037] Specifically, since the images taken by multiple aiming cameras include positioning point images and non-positioning point images, it is necessary to filter out the positioning point images from all the taken images, that is, the upper computer will receive all the positioning point image information about all the taken images, and filter out the image information of each positioning point from all the positioning point image information, thereby obtaining the positioning point image information of each positioning point.

[0038] Step S6: performing alignment according to the positioning point image information of each positioning point.

[0039] Specifically, in the prior art, it is impossible to determine each positioning point image after obtaining all images, so each positioning point image can only be obtained one by one and then positioned. For this reason, the image recognition algorithm is used in the present application to identify and process the positioning point image information of each positioning point to determine the position information of each positioning point in the positioning point image, and then the position information of each positioning point in the positioning point image is converted into the position information of each positioning point in the substrate, so as to realize the rapid alignment of the LDI exposure machine. Therefore, compared with the existing LDI exposure machine that aligns each positioning point one by one through the mutual vector movement of the control machine and the motion platform, in the present application, after all the positioning point image information is obtained at one time, the positioning point image information of each positioning point can be screened and obtained, and then the positioning is performed through the positioning image information of each positioning point, instead of obtaining each positioning point image one by one and then positioning, but by controlling the motion platform to move along the length direction of the substrate and controlling the camera to move along the width direction of the substrate, so as to maximize the multi-zone alignment speed of the LDI exposure machine and avoid the problem of reduced production capacity of the LDI exposure machine. In addition, multiple alignment cameras can synchronously capture images at the same time, thereby avoiding the problem of camera redundancy.

[0040] It should be noted that the alignment method of the LDI exposure machine in the present application is applicable to aligning all regularly distributed positioning points on the substrate.

[0041] According to the alignment method of the LDI exposure machine of the embodiment of the present invention, each alignment camera is driven to move according to the corresponding optimal acquisition path, and then the motion platform is driven to move back and forth between the starting point and the end point of the substrate, and each time the motion platform moves to the shooting interval distance, it triggers multiple alignment cameras to shoot images, so as to obtain all image information at one time, and then filter and obtain the positioning point image information of each positioning point for positioning. Therefore, compared with the existing LDI exposure machine that aligns each positioning point one by one through the mutual vector movement of the control machine and the motion platform, in the present application, after all the positioning point image information is obtained at one time, the positioning point image information of each positioning point can be obtained after filtering and then positioning is performed through the positioning image information of each positioning point, instead of obtaining each positioning point image one by one and then positioning, but by controlling the motion platform to move along the length direction of the substrate and controlling the camera to move along the width direction of the substrate, the alignment speed of the LDI exposure machine can be maximized. In addition, multiple alignment cameras can synchronously shoot images at the same time, thereby avoiding the problem of camera redundancy.

[0042] In some embodiments, the optimal acquisition path corresponding to each alignment camera is determined according to the GDS drawing information, including: rasterizing the GDS drawing information to obtain row-column relationship results of all positioning points and GDS coordinate information of each positioning point; determining the alignment camera corresponding to each column of positioning points in the row-column relationship results; and performing path planning according to the GDS coordinate information of the first positioning point in each column in the row-column relationship results corresponding to each alignment camera to obtain the optimal acquisition path corresponding to each alignment camera, wherein the first positioning point in each column is a positioning point on the substrate close to the starting point of the substrate.

[0043] Specifically, the GDS drawing information is input into the upper computer software for rasterization processing, that is, the upper computer obtains the GDS coordinate information of each positioning point, so as to obtain the row-column relationship results of all the positioning points according to the GDS coordinate information of each positioning point, and then determines the alignment camera corresponding to each column of the positioning points in the row-column relationship results, that is, determines which specific alignment camera is responsible for collecting the image of each column of the positioning points in the row-column relationship results. For determining the alignment camera corresponding to each column of the positioning points, the shooting range and position information of each alignment camera and the GDS coordinate information of each column of the positioning points can be combined to determine the distance between each column of the positioning points in the row-column relationship results and each alignment camera, and then According to the distance between each column of positioning points and each alignment camera, the alignment camera corresponding to each column of positioning points in the row-column relationship result is determined, and then path planning is performed for all column positioning points assigned to each alignment camera. Specifically, since all positioning points on the substrate are regularly distributed, path planning can be performed through the GDS coordinate information of the first positioning point in each column assigned to each alignment camera, that is, the GDS coordinate information of the first positioning point in each column assigned to each alignment camera is input into the path planning algorithm to obtain the optimal acquisition path corresponding to each alignment camera, so as to reduce the number of movements and the movement path of the motion platform, thereby reducing the exposure machine alignment time and improving the exposure machine's productivity.

[0044] Exemplarily, the present application uses three alignment cameras as an example for description, from left to right they are the first alignment camera, the second alignment camera and the third alignment camera, the row and column relationship result is nine columns, the first column positioning points, the second column positioning points and the third column positioning points are closest to the first alignment camera, the first column positioning points, the second column positioning points and the third column positioning points are assigned to the first alignment camera, and then the first positioning point in the first column positioning points, the second column positioning points and the third column positioning points is path planned to obtain the optimal path planning corresponding to the first alignment camera; the fourth column positioning points, the fifth column positioning points and the sixth column positioning points are closest to the second alignment camera Recently, the fourth column of positioning points, the fifth column of positioning points and the sixth column of positioning points are assigned to the second alignment camera, and then path planning is performed on the first positioning point in the fourth column of positioning points, the fifth column of positioning points and the sixth column of positioning points to obtain the optimal path planning corresponding to the second alignment camera; the seventh column of positioning points, the eighth column of positioning points and the ninth column of positioning points are closest to the third alignment camera, and the seventh column of positioning points, the eighth column of positioning points and the ninth column of positioning points are assigned to the third alignment camera, and then path planning is performed on the first positioning point in the seventh column of positioning points, the eighth column of positioning points and the ninth column of positioning points to obtain the optimal path planning corresponding to the third alignment camera.

[0045] In an embodiment, based on the coordinate information of the positioning points in two directions in the GDS drawing information, when the distance between the two positioning points in two directions is less than a preset threshold, where the preset threshold can be 1 mm, then the two positioning points are confirmed to be adjacent positioning points, and the adjacent positioning points are located in the same field of view, that is, the same row and the same column, then the adjacent positioning points are collected by the same alignment camera.

[0046] In some embodiments, determining the alignment camera corresponding to each column of the positioning point in the row-column relationship result includes: obtaining the acquisition area boundary of each alignment camera; determining the alignment camera corresponding to each column of the positioning point in the row-column relationship result based on the GDS coordinate information of the first positioning point in each column in the row-column relationship result and the acquisition area boundary of each alignment camera.

[0047] Among them, the acquisition area limit refers to the image acquisition range of the substrate for the alignment camera. The acquisition area limit can be calculated based on the camera parameters and geometric optical principles to obtain the boundary and size of the acquisition area. The acquisition area limit can be represented by the substrate coordinate system. The acquisition area limit is calculated in advance before the positioning points on the substrate are aligned.

[0048] Specifically, the acquisition area range can be calculated based on the camera parameters and the principle of geometric optics, and then the acquisition area range can be converted to the substrate coordinate system according to the position of each alignment camera to obtain the acquisition area limit of each alignment camera, or the acquisition area limit of the camera can be determined by shooting an image with an alignment camera and observing the boundary position of the target area in the image, and then the coordinate information of the first positioning point in each column in the substrate coordinate system can be obtained according to the GDS coordinate information of the first positioning point in each column, and then the relative distance between the first positioning point in each column and the acquisition area limit corresponding to each alignment camera can be calculated according to the coordinate information of the first positioning point in each column in the substrate coordinate system and the acquisition area limit of each alignment camera, so as to determine the alignment camera with the shortest relative distance between the first positioning point in each column and each acquisition area limit, and use the alignment camera as the alignment camera corresponding to each positioning point in the row-column relationship result, thereby determining the alignment camera corresponding to each positioning point in the row-column relationship result. In addition, it should be noted that the substrate coordinate information of the first positioning point in each column in the width direction of the substrate can be used for the relative distance calculation.

[0049] In some embodiments, path planning is performed based on the GDS coordinate information of the first positioning point in each column in the row-column relationship result corresponding to each alignment camera to obtain the optimal acquisition path corresponding to each alignment camera, including the following steps: First, get the pathfinder corresponding to each camera.

[0050] The pathfinder can be a computer program used to find the best path from the starting point to the end point in a space such as a graph, a map, or a network. This path can be defined as the shortest path, the fastest path, or a path that meets certain conditions. The number of pathfinders is consistent with the number of aiming cameras. For example, when the number of aiming cameras is 3, the number of correspondingly configured pathfinders is also 3.

[0051] Specifically, a pathfinder corresponding to each aiming camera is obtained, and the pathfinder is used to plan a collection path corresponding to each aiming camera.

[0052] Secondly, the starting position information of each pathfinder is determined according to the GDS coordinate information of the first positioning point in each column.

[0053] Specifically, the GDS coordinate information of the first positioning point in each column corresponding to the row and column relationship results of each aiming camera is used to determine the first positioning point in a column closest to each aiming camera, and the GDS coordinate information of the first positioning point is used as the starting position information of each pathfinder.

[0054] Again, based on the starting position information of each pathfinder and the GDS coordinate information of the first positioning point in each column, determine the acquisition path corresponding to each aiming camera, and add the acquisition path to the alternative path set corresponding to each aiming camera until the number of acquisition paths in the alternative path set corresponding to each aiming camera reaches the preset number.

[0055] The preset number can be understood as the number of path iterations that are preset in advance by the pathfinder. The preset number can be set according to the time to obtain the final collection path. The setting of the preset number affects the depth of the algorithm search. More iterations usually mean a better collection path, but it may also increase the time to calculate the collection path. Therefore, setting a reasonable preset number usually requires balancing computing resources and path diversity. The preset number can be adjusted according to specific circumstances.

[0056] Specifically, the pathfinder corresponding to each aiming camera performs path planning according to the starting position information of each pathfinder and the GDS coordinate information of the first positioning point in each column to determine the collection path corresponding to each aiming camera with respect to the first positioning point in each column, and add the collection path to the set of alternative paths corresponding to each aiming camera, and then determine whether the number of collection paths in the set of alternative paths corresponding to each aiming camera reaches a preset number. If not, it means that the optimal collection path is not obtained in the set of alternative paths corresponding to each aiming camera, that is, the path quality of the collection path obtained by the pathfinder corresponding to each aiming camera does not meet the standard, then the pathfinder corresponding to each aiming camera continues to perform path planning. If so, it means that the optimal collection path is obtained in the set of alternative paths corresponding to each aiming camera, that is, the path quality of the collection path obtained by the pathfinder corresponding to each aiming camera meets the standard, and the efficiency of the pathfinder corresponding to each aiming camera in obtaining the collection path is high, then the pathfinder corresponding to each aiming camera stops performing path planning.

[0057] Then, the shortest acquisition path in the candidate path set corresponding to each aligned camera is determined.

[0058] The shortest acquisition path is the shortest acquisition sequence or path for each alignment camera to move to the first positioning point in each column in the corresponding row and column relationship result.

[0059] Finally, the shortest acquisition path in the candidate path set corresponding to each aiming camera is used as the optimal acquisition path corresponding to each aiming camera, so as to shorten the moving distance of each aiming camera, thereby effectively improving the moving speed of each aiming camera.

[0060] Reference below Figure 3 The following is an example of the alignment method of the LDI exposure machine according to the embodiment of the present invention, and the specific contents are as follows.

[0061] Step S7, obtaining the GDS coordinate information of all positioning points on the substrate.

[0062] Step S8, setting initialization parameters such as the number of pathfinders and the preset number.

[0063] Step S9, creating a pathfinder for each aiming camera, and setting and recording the starting position information of each pathfinder.

[0064] Step S10, based on the starting position information of each pathfinder and the GDS coordinate information of the first positioning point in each column, determine the acquisition path corresponding to each aiming camera, and add the acquisition path to the alternative path set corresponding to each aiming camera to update the alternative path set and update the number of times each positioning point is passed by the pathfinder in real time.

[0065] Step S11, determining whether the number of acquisition paths in the candidate path set corresponding to each alignment camera reaches a preset number, if so, executing step S12, if not, executing step S9.

[0066] Step S12: taking the shortest acquisition path in the candidate path set as the optimal acquisition path corresponding to each alignment camera.

[0067] Based on the above, in this application, by determining the shortest acquisition path in the set of alternative paths corresponding to each alignment camera, and using it as the optimal acquisition path corresponding to each alignment camera, the acquisition efficiency of the positioning point image can be significantly improved, and the time and resources consumed in the acquisition process can be effectively reduced. Unnecessary path detours and repetitions can be avoided, so that the alignment of the substrate positioning points can be more efficient.

[0068] In some embodiments, a limit switch is provided at the end point of the motion platform to control the motion platform to move back and forth between the starting point and the end point of the substrate, including: when it is determined that the alignment camera is located above the first positioning point in each column of the optimal acquisition path, the motion platform is controlled to move forward along the length direction of the substrate; when it is determined that the motion platform triggers the limit signal of the limit switch, the motion platform is controlled to move in the reverse direction along the length direction of the substrate.

[0069] Specifically, the optimal acquisition path is the movement order of the alignment camera for the first positioning point in each column corresponding to the row-column relationship result. When each alignment camera is driven to move to the top of the first positioning point in each column in the optimal acquisition path, in order to obtain the positioning point images of all the positioning points in the column where the first positioning point is located, refer to Figure 4 (a) and Figure 4 (b). Drive the motion platform to move forward along the length direction of the substrate from the starting point of the substrate. Since the shooting field of view of the alignment camera for the substrate is fixed, the shooting interval distance is set according to the shooting field of view of the alignment camera, and all the positioning points on the substrate are divided into multiple substrate shooting areas in the length direction of the substrate according to the shooting interval distance. When the real-time moving distance of the motion platform reaches the shooting interval distance every time, When leaving, the motion platform loaded with the substrate moves to the unphotographed substrate shooting area, which triggers an image acquisition signal, so that each alignment camera synchronously acquires the image information in the substrate shooting area until the motion platform triggers the limit signal of the limit switch. At this time, it means that each alignment camera has acquired the image information in all areas on the substrate, that is, each alignment camera obtains the positioning point images of all positioning points in the column where the first positioning point is located, and then controls the motion platform to move in the opposite direction along the length direction of the substrate, so that the motion platform returns to the starting point of the motion platform on the substrate, so that each alignment camera continues to capture all positioning point images in the column where the other first positioning points are located, and so on, until each alignment camera captures the positioning point images of each column assigned to it.

[0070] After each alignment camera has captured the image of the positioning points of each assigned column, if there are still uncaptured areas of the substrate, that is, there are other unassigned columns in the row-column relationship result, control the multiple alignment cameras and the motion platform to move toward each other so that the multiple alignment cameras move to the uncaptured areas of the substrate, and reallocate other unassigned columns in the row-column relationship result to each alignment camera.

[0071] Exemplarily, taking the first alignment camera collecting the positioning point images of each column of positioning points assigned as an example, the first column of positioning points, the second column of positioning points and the third column of positioning points are assigned to the first alignment camera, each column of positioning points includes three positioning points, the first positioning point of the first column of positioning points is positioning point A1, the first positioning point of the second column of positioning points is positioning point B1, and the first positioning point of the third column of positioning points is positioning point C1, then the optimal collection path of the first alignment camera for these three columns of positioning points is the shooting order of positioning point A1, positioning point B1 and positioning point C1. If the optimal collection path is to first collect positioning point A1, then collect positioning point B1 and finally collect positioning point C, based on this, when the first alignment camera is driven to move above positioning point A1 in the optimal collection path, the motion platform is driven from the substrate The motion platform starts to move forward along the length direction of the substrate from the starting point. When the upper computer monitors that the real-time moving distance of the motion platform reaches the shooting interval distance, an image acquisition signal is triggered and sent to the first alignment camera, so that the first alignment camera collects image information within the shooting interval distance until the motion platform triggers the limit signal of the limit switch. At this time, it means that the first alignment camera collects the positioning point images of positioning point A1, positioning point A2 and positioning point A3, and then controls the motion platform to move in the opposite direction along the length direction of the substrate, so that the motion platform returns to the starting point of the motion platform on the substrate, so that the first alignment camera continues to capture all the positioning point images in the column where positioning point B1 is located, and so on, until the first alignment camera finishes capturing the positioning point images of the assigned column.

[0072] In addition, it should be noted that when the first aiming camera captures the positioning point image of the assigned column, the remaining aiming cameras synchronously capture the positioning point images of their corresponding columns.

[0073] Therefore, in the present application, by controlling the motion platform to move back and forth between the starting point and the end point of the substrate, the multi-zone alignment path distance is shortened, so that each alignment camera can efficiently obtain the positioning point images of all columns assigned to it, ensuring the continuity and integrity of the positioning point image acquisition process, thereby maximizing the alignment speed of the LDI exposure machine.

[0074] In some embodiments, the positioning point image information of each positioning point is determined based on all the image information, including: obtaining the GDS coordinate mapping relationship about the positioning point, and obtaining the acquired image size information of the alignment camera; and filtering out the positioning point image information of each positioning point in all the image information based on the GDS coordinate mapping relationship and the acquired image size information.

[0075] Specifically, the GDS coordinate mapping relationship of the positioning points and the size information of the captured image of the alignment camera are obtained. Since the GDS coordinate information of each positioning point exists in the GDS drawing about the positioning points, the GDS coordinate information of each positioning point in the GDS drawing is obtained to determine the association information between each positioning point through the GDS coordinate information of each positioning point. For example, the association information can be the positional relationship between each positioning point or the distance between each positioning point. For example, the GDS coordinate information of one positioning point is expressed as (X1, Y1), and the GDS coordinate information of another positioning point is expressed as (X2, Y2). Then, the positional relationship between each positioning point is (X1-X2, Y1-Y2), and the association information between each positioning point is used as the GDS coordinate mapping relationship of the positioning point in the GDS drawing.

[0076] Then, the positioning point image information of each positioning point in all the image information is filtered out according to the GDS coordinate mapping relationship and the collected image size information. That is to say, since the positioning points on the substrate are prepared according to the GDS coordinate information of each positioning point in the GDS drawing, the GDS coordinate mapping relationship of the positioning points is the mapping relationship between the positioning points on the substrate. Based on this, the association information between each positioning point is determined through the GDS coordinate information of each positioning point, that is, through the positional relationship between each positioning point or the distance between each positioning point, the upper computer obtains multiple images collected by each alignment camera and determines the positioning point image of the reference point, and determines the reference point and other positioning points according to the GDS coordinate mapping relationship. The distance in the length direction and the width direction is then converted into the number of pictures in the length direction and the width direction according to the acquired image size information, so as to determine the positioning point image of each positioning point from all the images acquired by multiple alignment cameras according to the number of pictures in the length direction and the width direction. In the present application, the positioning point image of each positioning point is obtained by screening from all the images taken by multiple alignment cameras through the GDS coordinate mapping relationship and the acquired image size information, so that it is possible to wait until all images are acquired before aligning through the image of each positioning point, instead of obtaining each positioning point image one by one and then positioning, thereby maximizing the positioning speed and improving the alignment speed of the LDI exposure machine.

[0077] In some embodiments, the alignment method also includes: determining an initial recognition position of each positioning point in the corresponding positioning point image information; determining a mapping relationship function between the positioning point image information about the same positioning point collected by each adjacent two alignment cameras among multiple alignment cameras; determining a final recognition position of each positioning point in the corresponding positioning point image information based on the mapping relationship function and the initial recognition position; and determining a substrate position recognition result of each positioning point based on the final recognition position of each positioning point.

[0078] Specifically, in order for the positional relationship between the positioning points in the images taken by all alignment cameras to reflect the positional relationship between the positioning points of the substrate, the present application uses a mapping relationship function between the image information of the positioning points collected by each adjacent two alignment cameras among multiple alignment cameras to associate the image position information of the positioning points in the images taken by all alignment cameras. Specifically, the positional relationship between the same positioning points in the positioning point image information collected by each two adjacent alignment cameras among the multiple alignment cameras is used as the conversion relationship between the positioning point image information collected by each two adjacent alignment cameras among the multiple alignment cameras, and then the conversion relationship between the positioning point image information collected by each two adjacent alignment cameras among the multiple alignment cameras is used as the mapping relationship function between the positioning point image information collected by each two adjacent alignment cameras among the multiple alignment cameras, and then the final recognition position of each positioning point in the corresponding positioning point image information is calculated through the mapping relationship function between the initial recognition position of each positioning point in the corresponding positioning point image information and the positioning point image information collected by the corresponding two adjacent alignment cameras, wherein the final recognition position of all positioning points in the corresponding positioning point image information can reflect the positional relationship between all positioning points of the substrate, and the final recognition position of each positioning point in the corresponding positioning point image information is converted to the substrate coordinate system according to the final recognition position of each positioning point in the corresponding positioning point image information, so that the substrate coordinate information of the converted positioning point is used as the substrate position recognition result of each positioning point, thereby realizing the alignment of the LDI exposure machine.

[0079] In some embodiments, a mapping relationship function between image information about the same positioning point collected by each adjacent two alignment cameras among a plurality of alignment cameras is determined, including: for the positioning point image information collected by each alignment camera, determining the image coordinate information of each positioning point in the corresponding positioning point image information; and determining the mapping relationship function between the image information about the same positioning point collected by each adjacent two alignment cameras based on the image coordinate information of each positioning point.

[0080] Specifically, for each two adjacent alignment cameras, the image coordinate information of each positioning point in the positioning point image information collected by each alignment camera is determined, that is, the positioning point image information collected by each alignment camera in the two adjacent alignment cameras is obtained, and then the image coordinate information of each positioning point in the positioning point image information is identified by an image recognition algorithm, and the image coordinate information of the positioning point in the same positioning point image collected by each alignment camera in the two adjacent alignment cameras is determined, and then the conversion relationship between the image coordinate information of the same positioning point photographed by the two adjacent alignment cameras is calculated, and the conversion relationship can be the image coordinate difference of the same positioning point photographed by the adjacent alignment cameras, so as to calculate the mapping relationship function between the positioning point image information collected by each two adjacent alignment cameras through the conversion relationship between the image coordinate information of the same positioning point photographed by the adjacent alignment cameras, for example, the conversion relationship between the image coordinate information of a certain same positioning point is used as the mapping relationship function between the image coordinate information of the positioning points collected by the adjacent alignment cameras. Among them, the conversion relationship between the image coordinate information of a certain same positioning point can be the most accurate conversion relationship among the conversion relationships between the image coordinate information of all the same positioning points. Alternatively, the final conversion relationship may be calculated through the conversion relationship between the image coordinate information of all the same positioning points, so that the final conversion relationship is used as a mapping relationship function between the image information of the positioning points collected by adjacent alignment cameras.

[0081] Exemplarily, the first alignment camera and the second alignment camera are two adjacent alignment cameras, a column of positioning points with equal width and spacing on the substrate are selected, and then the first alignment camera and the second alignment camera are used to shoot the selected column of positioning points to obtain positioning point images of the positioning points respectively, and then the image recognition algorithm is used to identify the image coordinate information of each positioning point in the positioning point image shot by the first alignment camera and the second alignment camera for each same positioning point, and the conversion relationship between the image coordinate information of the same positioning point shot by the first alignment camera and the second alignment camera is calculated. The conversion relationship can be the image coordinate difference of the same positioning point shot by the first alignment camera and the second alignment camera, for example, The coordinates of a positioning point are identified as A (X3, Y3) by the positioning point image of a positioning point captured by the first alignment camera, and the coordinates of the positioning point are identified as B (X4, Y4) by the positioning point image of the same positioning point captured by the first alignment camera. Then, the conversion relationship can be (X3-X4, Y3-Y4), so as to determine the mapping relationship function between the positioning point image information captured by the first alignment camera and the second alignment camera through the conversion relationship between the image coordinate information of the same positioning point captured by the first alignment camera and the second alignment camera. For example, the conversion relationship between the image coordinate information of a certain same positioning point is used as the mapping relationship function between the image coordinate information of the positioning point captured by the first alignment camera and the second alignment camera. Among them, the conversion relationship between the image coordinate information of a certain same positioning point can be the most accurate conversion relationship among the conversion relationships between the image coordinate information of all the same positioning points.

[0082] In addition, it should be noted that if there is another adjacent third alignment camera to the second alignment camera, the third alignment camera and the second alignment camera are aligned in the above manner to obtain a mapping relationship function between the positioning point image information collected by the second alignment camera and the third alignment camera.

[0083] Based on this, the image information of the positioning points collected by all cameras is associated with each other through a mapping relationship function between the image information of the positioning points collected by two adjacent alignment cameras.

[0084] In some embodiments, the substrate position recognition result of each positioning point is determined according to the final recognition position of each positioning point, including: determining the mapping relationship between the image coordinate information about the positioning point and the substrate coordinate information; performing position conversion on the final recognition position of each positioning point according to the mapping relationship to determine the substrate position recognition result of each positioning point.

[0085] The substrate coordinate information is the coordinate information of the positioning point in the substrate in the substrate coordinate system.

[0086] Exemplarily, one or more positioning points in the substrate that can be clearly distinguished from other positioning points are selected, and the positioning points can be located at the upper left corner, the lower corner, the upper right corner or the lower right corner of the substrate. The user manually inputs the coordinate information of the positioning point in the substrate coordinate system, or uses the GDS coordinate information of the positioning point as the substrate coordinate information of the positioning point, and the controller obtains the substrate coordinate information of the positioning point, and then uses the alignment camera to shoot the image coordinate information of the positioning point, and then calculates the association information between the image coordinate information of the positioning point and the substrate coordinate information through the image coordinate information of the positioning point and the substrate coordinate information, so as to use the association information between the image coordinate information of the positioning point and the substrate coordinate information as the mapping relationship between the image coordinate information of the positioning point and the substrate coordinate information, and then converts the final recognition position of each positioning point according to the mapping relationship to determine the substrate position recognition result of each positioning point, for example, the final recognition position of each positioning point minus the mapping relationship to obtain the substrate position recognition result of each positioning point.

[0087] Finally, the controller can also calculate the rotation, translation and expansion / contraction information of each positioning point according to the substrate position recognition result of each positioning point and the GDS coordinate information of each positioning point.

[0088] Reference below Figure 5 The alignment method of the LDI exposure machine according to an embodiment of the present invention is described, and the specific contents are as follows.

[0089] Step S13: the host computer obtains the GDS coordinate information of all positioning points.

[0090] Step S14, performing path planning according to the GDS coordinate information of the first positioning point in each column corresponding to the row-column relationship result of each alignment camera, so as to obtain the optimal acquisition path corresponding to each alignment camera.

[0091] Step S15, controlling each alignment camera to move to above the first positioning point in each column in the corresponding optimal acquisition path.

[0092] Step S16, controlling the moving platform to accelerate from the starting point of the substrate, and starting to move at a uniform speed along the length direction of the substrate after the moving platform moves to the trigger starting point.

[0093] Step S17: When the controller detects that the real-time moving distance of the motion platform reaches the shooting interval distance, an image acquisition signal is triggered once, and the controller sends the image acquisition signal to the PSO board.

[0094] Step S18, after receiving the image acquisition signal, the PSO board performs voltage boosting processing on the image acquisition signal, and then synchronously transmits it to each light source controller.

[0095] Step S19: After receiving the image acquisition signal, the light source controller synchronizes the image acquisition signal to multiple alignment cameras and light sources, and executes steps S22 and S20.

[0096] In step S20, each alignment camera captures all images of the motion platform during the motion process along the length direction of the substrate and stores them in the image queue of the corresponding alignment camera, and then executes step S23.

[0097] Step S21, when the motion platform moves to the limit switch, a limit signal is triggered to control the motion platform to move in the opposite direction along the length direction of the substrate, and an image acquisition stop signal is triggered and sent to the controller. The controller sends an image acquisition stop signal to the PSO board to control multiple alignment cameras to stop acquiring images.

[0098] Step S22, controlling the light source to strobe according to the image acquisition signal.

[0099] Step S23, filtering out the positioning point image information of each positioning point in all the image information according to the GDS coordinate mapping relationship and the image size information, and deleting all the images except the images containing the positioning points.

[0100] Step S24, performing image recognition on the positioning point image of each positioning point through an image recognition algorithm to obtain an initial recognition position of each positioning point in the corresponding positioning point image information, and then obtaining a final recognition position of each positioning point in the corresponding positioning point image information based on a mapping relationship function between the positioning point image information about the same positioning point collected by each adjacent two alignment cameras in the multiple alignment cameras, and determining a substrate position recognition result of each positioning point based on the final recognition position of each positioning point, and calculating rotation, translation and expansion and contraction information between the substrate position recognition result of each positioning point and the substrate coordinate information of each positioning point.

[0101] Step S25, the substrate position recognition result of each positioning point is counted to complete the LDI exposure machine alignment.

[0102] A second aspect of the present invention provides an LDI exposure machine, referring to Figure 1 As shown, the LDI exposure machine 10 includes a plurality of alignment cameras 7, a motion platform and a controller 2. The plurality of alignment cameras 7 are arranged in a line along the width direction of the substrate 8, and each alignment camera 7 is used to collect image information of a positioning point on the substrate 8 in response to an image acquisition signal; the motion platform is located below the plurality of alignment cameras 7, and the motion platform is used to pull the substrate 8 to move; the controller 2 is connected to the motion platform and the plurality of alignment cameras 7, and is used to execute the alignment method of the LDI exposure machine of the above-mentioned embodiment.

[0103] According to the LDI exposure machine 10 of the embodiment of the present invention, by executing the alignment method of the LDI exposure machine of the above embodiment, the alignment speed of the LDI exposure machine can be maximized when there are many positioning point partitions on the substrate 8.

[0104] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative 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.

[0105] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for aligning an LDI exposure machine, characterized in that: The LDI exposure machine includes a motion platform for pulling the substrate to move and a plurality of alignment cameras, the plurality of alignment cameras are arranged in a line along the width direction of the substrate, the motion platform is located below the plurality of alignment cameras, and the alignment method includes: Get GDS drawing information about the positioning point; Determine the optimal acquisition path corresponding to each alignment camera according to the GDS drawing information; Control each alignment camera according to the optimal acquisition path corresponding to each alignment camera; Controlling the motion platform to move back and forth between the starting point and the end point of the substrate until the alignment camera completes image acquisition of all positioning points, wherein an image acquisition signal is triggered once each time the real-time moving distance of the motion platform reaches the shooting interval distance, and the image acquisition signal is used to instruct multiple alignment cameras to synchronously acquire image information; Determine the positioning point image information of each positioning point according to all the image information; Alignment is performed based on the positioning point image information of each positioning point.

2. The alignment method of the LDI exposure machine according to claim 1, characterized in that: Determining the optimal acquisition path corresponding to each alignment camera according to the GDS drawing information includes: The GDS drawing information is rasterized to obtain row and column relationship results of all positioning points and GDS coordinate information of each positioning point; Determine the alignment camera corresponding to each column of positioning points in the row-column relationship result; Path planning is performed based on the GDS coordinate information of the first positioning point in each column corresponding to the row-column relationship result of each alignment camera to obtain the optimal acquisition path corresponding to each alignment camera, wherein the first positioning point in each column is a positioning point on the substrate close to the starting point of the substrate.

3. The alignment method of the LDI exposure machine according to claim 2, characterized in that: Determining the alignment camera corresponding to each column of the positioning points in the row-column relationship result includes: Get the acquisition area limits of each camera; The alignment camera corresponding to each column of the row-column relationship result is determined according to the GDS coordinate information of the first positioning point in each column of the row-column relationship result and the acquisition area boundary of each alignment camera.

4. The alignment method of the LDI exposure machine according to claim 2, characterized in that: Performing path planning according to the GDS coordinate information of the first positioning point in each column corresponding to the row-column relationship result of each alignment camera to obtain the optimal acquisition path corresponding to each alignment camera, including: Get the pathfinder corresponding to each camera; Determine the starting position information of each pathfinder according to the GDS coordinate information of the first positioning point in each column; Determine the acquisition path corresponding to each alignment camera according to the starting position information of each pathfinder and the GDS coordinate information of the first positioning point in each column, and add the acquisition path to the set of candidate paths corresponding to each alignment camera until the number of acquisition paths in the set of candidate paths corresponding to each alignment camera reaches a preset number; Determine the shortest acquisition path in the set of candidate paths corresponding to each aligned camera; The shortest acquisition path in the candidate path set corresponding to each aligned camera is used as the optimal acquisition path corresponding to each aligned camera.

5. The alignment method of the LDI exposure machine according to claim 1, characterized in that: A limit switch is provided at the end point of the motion platform to control the motion platform to move back and forth between the start point of the substrate and the end point of the substrate, including: When it is determined that the alignment camera is located above the first positioning point in each column of the optimal acquisition path, controlling the motion platform to move forward along the length direction of the substrate; When it is determined that the motion platform triggers the limit signal of the limit switch, the motion platform is controlled to move in the reverse direction along the length direction of the substrate.

6. The alignment method of the LDI exposure machine according to claim 1, characterized in that: Determine the image information of each positioning point based on all the image information, including: Obtaining the GDS coordinate mapping relationship of the positioning point and obtaining the image size information collected by the alignment camera; The positioning point image information of each positioning point in all the image information is filtered out according to the GDS coordinate mapping relationship and the acquired image size information.

7. The alignment method of the LDI exposure machine according to any one of claims 1 to 6, characterized in that: The alignment method further comprises: Determine the initial recognition position of each positioning point in the corresponding positioning point image information; Determine a mapping relationship function between the positioning point image information about the same positioning point collected by each two adjacent positioning cameras among the multiple positioning cameras; Determine the final recognition position of each positioning point in the corresponding positioning point image information according to the mapping relationship function and the initial recognition position; The substrate position recognition result of each positioning point is determined according to the final recognition position of each positioning point.

8. The alignment method of the LDI exposure machine according to claim 7, characterized in that: Determining a mapping relationship function between image information collected by each two adjacent alignment cameras about the same positioning point among the multiple alignment cameras includes: For each positioning point image information collected by the alignment camera, determine the image coordinate information of each positioning point in the corresponding positioning point image information; A mapping relationship function between image information on the same positioning point collected by every two adjacent alignment cameras is determined according to the image coordinate information of each positioning point.

9. The alignment method of the LDI exposure machine according to claim 8, characterized in that: The substrate position recognition result of each positioning point is determined according to the final recognition position of each positioning point, including: Determine a mapping relationship between image coordinate information about a positioning point and substrate coordinate information; The final identified position of each positioning point is converted according to the mapping relationship to determine the substrate position identification result of each positioning point.

10. An LDI exposure machine, characterized in that: include: A plurality of alignment cameras, wherein the plurality of alignment cameras are arranged in a line along the width direction of the substrate, and each alignment camera is used to acquire image information of a positioning point on the substrate in response to an image acquisition signal; A motion platform, the motion platform is located below the plurality of alignment cameras, and the motion platform is used to pull the substrate to move; A controller, wherein the controller is connected to the motion platform and the plurality of alignment cameras, and is used to execute the alignment method of the LDI exposure machine according to any one of claims 1 to 9.

Images