Method for determining the position of positioning marks on parts to be bonded and bonding equipment

Abstract

The present invention relates to a method for determining the position of a positioning mark on a part to be bonded and a bonding device. The method comprises placing a standard part at a placement position of the part to be bonded; collecting image information at a shooting point and determining the standard pixel coordinates of the positioning mark in the image information; moving a marking mechanism and determining the standard positioning coordinates of the marking mechanism on the bonding device; determining a conversion coefficient k between pixels in the image information and the spatial dimensions of the bonding device; placing the part to be bonded at the placement position of the part to be bonded, still collecting image information of the corresponding positioning mark at the shooting point, and determining the target pixel coordinates of the positioning mark in the image information, thereby determining the position coordinates of the positioning mark of the bonding part on the bonding device. By positioning the positioning mark on the bonding device and the image information respectively, a connection is established between the image information and the bonding device, thereby achieving high-precision conversion of any coordinates in the image information to the coordinates of the bonding device.

Description

Technical Field

[0001] The present invention relates to the technical field of backlight sheet and segment code screen assembly, and in particular to a method for determining the position of a positioning mark on a component to be bonded and bonding equipment. Background Art

[0002] As the demand for segmented displays to display complex images grows, such as on car dashboards, the shape and size of the backlight's transparent area and the display area of the segmented screen must be consistent. This requires an increasingly high degree of overlap between the transparent and display areas after the segmented screen and backlight are bonded together, placing higher demands on the bonding accuracy of the segmented screen and backlight. Existing technology for bonding such segmented screens to backlights often relies on manual alignment. However, due to individual differences in bonding operators, this can lead to inaccurate alignment, low product yields, and low bonding efficiency. Furthermore, bonding is performed under strong sunlight, which can cause certain eye damage to the operator.

[0003] Prior art CN114619233A proposes a locking and positioning method, a screw locking method, a locking and positioning device, and a screw machine. This method uses a camera calibration plate to enable conversion between the camera coordinate system {V} and the base coordinate system {B} via the local coordinate system {M}. This requires pre-positioning multiple reference points and converting back and forth between the three coordinate systems, resulting in cumbersome calculations. Summary of the Invention

[0004] Based on the above situation, the main purpose of the present invention is to provide a method for determining the position of the positioning mark on the part to be bonded and a bonding device. By positioning the positioning mark on the bonding device and the image information respectively, a connection between the image information and the bonding device is established, so that any coordinates in the image information can be converted into the coordinates of the bonding device with high precision.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A method for determining the position of a to-be-laminated part on a laminating device, used for aligning a segment code screen and a backlight sheet when laminating them, wherein the to-be-laminated part includes a segment code screen and a backlight sheet, both of which are provided with corresponding positioning marks; the laminating device is provided with a placement position for the to-be-laminated part, a movable marking mechanism, and relatively fixed shooting points, and when the to-be-laminated part is placed in the to-be-laminated position, there is a corresponding shooting point directly above each positioning mark; the position determination method comprises the steps of:

[0007] S100, placing one of the parts to be bonded as a standard part at the placement position of the parts to be bonded; collecting image information of the corresponding positioning mark at the shooting point, and determining the standard pixel coordinates (x1, y1) of the positioning mark in the image information;

[0008] S200, moving the marking mechanism so that it is located directly above the positioning mark, and determining the standard positioning coordinates (X1, Y1) of the marking mechanism on the laminating device. The position of the positioning mark of the standard component is (X1, Y1);

[0009] S300, determining a conversion coefficient k between pixels in the image information and the spatial size of the fitting device;

[0010] Perform step S400 on each piece to be bonded:

[0011] S400, placing the to-be-bonded piece at the to-be-bonded piece placement position, still capturing the corresponding image information of the positioning mark at the shooting point, and determining the target pixel coordinates S'(x2, y2) of the positioning mark in the image information. The position coordinates S(x2, y2) of the positioning mark of the to-be-bonded piece on the bonding device are:

[0012] X2=X1+(x2-x1)*k;

[0013] Y2=Y1+(y2-y1)*k;

[0014] Wherein, the two horizontal axes of the coordinate system in the laminating device and the image information are respectively parallel.

[0015] Preferably, the marking mechanism comprises a positioning rod, and the positioning rod is vertically arranged;

[0016] In the step S100, the standard pixel coordinates are the coordinates of the center point of the positioning mark in the image information;

[0017] In step S200, the marking mechanism is adjusted so that the axis of the positioning rod is located directly above the center point of the positioning mark, and the coordinates of the positioning rod on the bonding device are the standard positioning coordinates.

[0018] Preferably, the lower end of the positioning rod is in a conical structure;

[0019] In the step S100, the standard pixel coordinates are the coordinates of the positioning mark in the image information;

[0020] In step S200, the marking mechanism is adjusted so that the tip of the conical structure is located directly above the center point of the positioning mark.

[0021] Preferably, the positioning mark is a cross-shaped structure or a hollow circle structure.

[0022] Preferably, a light source is provided on the lower side of the position where the workpiece to be bonded is placed; the positioning mark is a hollow circle structure, which is provided in the light-transmitting area on the workpiece to be bonded; the positioning rod is a cylindrical structure, and its outer diameter is equal to the diameter of the hollow circle structure;

[0023] In step S200, the marking mechanism is adjusted so that the lower end of the positioning rod blocks the light transmitted through the hollow circular structure. At this time, the coordinates of the positioning rod on the bonding device are the standard positioning coordinates.

[0024] Preferably, the step S300 includes the following steps:

[0025] S310, placing a ruler at the placement position of the bonding component, with the length direction of the ruler parallel to the x-axis or y-axis of the image information, and at least a portion of the ruler located directly below the shooting point; collecting ruler image information of the ruler at the shooting point;

[0026] S320 , obtaining the number of pixels A occupied by the preset length B of the ruler in the ruler image information, and obtaining k=B / A.

[0027] Preferably, the ratio of the preset length B to the maximum dimension of the positioning mark in the length direction is 1-3.

[0028] Preferably, two positioning marks are provided on the piece to be bonded, and there are multiple placement positions for the piece to be bonded, some of which are for placement of segment code screens and some of which are for placement of backlight sheets;

[0029] The position of each positioning mark of the piece to be bonded located at each placement position of the piece to be bonded is determined by the method of steps S100 to S400.

[0030] Preferably, the laminating device also includes a photographic device, which is connected to the marking mechanism so as to collect the image information at each of the shooting points through the same photographic device; at each of the shooting points, the optical axis of the photographic device is located near or passes through the shooting point.

[0031] The present invention also relates to a laminating device, wherein when the workpiece to be laminated is placed in a placement position for workpieces to be laminated, the position coordinates of the positioning mark on the workpiece to be laminated on the laminating device are determined using the aforementioned position determination method; the laminating device includes a workspace, wherein a three-axis moving mechanism, a marking mechanism, a camera device, and a placement platform are provided in the workspace;

[0032] The placing platform is arranged at the lower part of the working space, and a placement position for the parts to be bonded is provided on the placing platform;

[0033] The marking mechanism is mounted on the three-axis moving mechanism so as to be driven to move within the working space by the three-axis moving mechanism;

[0034] The shooting points are arranged in the working space, and the photographic equipment can reach each of the shooting points.

[0035] In the present invention, a corresponding fixed shooting point is set directly above each positioning mark. Since the position of the photographic equipment is the same when photographing the same positioning mark of each identical part to be bonded, it is only necessary to determine the standard pixel coordinates of the positioning mark on the standard part in the image information and the absolute coordinates of the positioning mark on the bonding equipment, as well as the conversion relationship between the spatial size of the bonding equipment and the number of pixels in the image information. Subsequently, for the part to be bonded, it is only necessary to determine the target pixel coordinates of the positioning mark thereon in the image information to determine its absolute coordinates on the bonding equipment. In this way, by determining the absolute positions of the corresponding positioning marks on the backlight sheet and the segment code screen, the backlight sheet can be moved to the segment code screen by mechanical equipment such as a robot to achieve precise alignment. This method of determining the position can avoid the problems of low yield, low bonding efficiency and damage to the operator's eyes caused by manual alignment; and there is no need to record the position of the photographic equipment in the absolute coordinate system each time, which can avoid the final conversion error caused by the uncertainty of the photographic equipment's shooting position each time; at the same time, this method is used to capture images of each positioning mark separately, rather than capturing multiple positioning marks at the same time in one picture. In this way, a small range of shooting is used to enable the positioning mark to be located in the center area of the image information, thereby minimizing the positioning error caused by shooting angle, image distortion, etc., and further improving the position accuracy of the positioning mark in the bonding equipment.

[0036] Other beneficial effects of the present invention will be explained through the introduction of specific technical features and technical solutions in the specific implementation methods. Those skilled in the art should be able to understand the beneficial technical effects brought about by the introduction of these technical features and technical solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The following describes a preferred embodiment of a method for determining the position of a positioning mark on a piece to be bonded and a bonding device according to the present invention with reference to the accompanying drawings.

[0038] Figure 1 A flowchart of a method for determining the position of a positioning mark on a piece to be bonded according to the present invention;

[0039] Figure 2 It is a structural diagram of the bonding equipment;

[0040] Figure 3 is a schematic diagram of standard pixel coordinates and target pixel coordinates in target image information;

[0041] Figure 4 It is a schematic diagram of the standard positioning coordinates and the target positioning coordinates in the mechanical coordinate system;

[0042] Figure 5 for Figure 4 Enlarged view of the S part in the middle.

[0043] In the figure: 1. Placement platform; 2. Marking mechanism; 3. Photographic equipment. DETAILED DESCRIPTION

[0044] The present invention is described below based on the following embodiments, but the present invention is not limited to these embodiments. In the following detailed description of the present invention, some specific details are described in detail. In order to avoid obscuring the essence of the present invention, well-known methods, processes, procedures, and components are not described in detail.

[0045] Furthermore, persons of ordinary skill in the art will appreciate that the figures provided herein are for illustration purposes only and are not necessarily drawn to scale.

[0046] Unless the context clearly requires otherwise, throughout the specification and claims, the words "include," "comprising," and similar words should be construed in an inclusive sense rather than an exclusive or exhaustive sense; that is, in the sense of "including but not limited to."

[0047] In the description of the present invention, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0048] See also Figure 1-Figure 5 The present invention relates to a method for determining the position of a positioning mark on a workpiece to be bonded on a bonding device, which is used for alignment when a segment code screen and a backlight sheet are bonded. The workpiece to be bonded includes a segment code screen and a backlight sheet, both of which are provided with corresponding positioning marks; the bonding device includes a camera device 3 arranged in a working space of the bonding device, a marking mechanism 2 that can move in the working space, and a horizontally arranged placement platform 1.

[0049] The placement platform 1 is provided with a placement position for the piece to be bonded, and the piece to be bonded is placed at the placement position for the piece to be bonded. The shape of the placement position for the piece to be bonded matches the shape of the piece to be bonded, so that the piece to be bonded can only be set at a specific placement angle with the placement position for the piece to be bonded. A positioning mark is provided on the piece to be bonded, and the positioning mark is located at a specific position of the piece to be bonded, so that no matter which piece to be bonded is placed at the placement position for the piece to be bonded, the positioning mark is basically at the same position on the placement platform 1. There is a shooting point corresponding to the positioning mark in the workspace, and the shooting point is located directly above the positioning mark. The shooting point is a specific point. When the piece to be bonded is placed at the placement position for the piece to be bonded, the positioning mark is located directly below the shooting point. In some embodiments, the number of positioning marks on the piece to be bonded is more than one, for example, two or more. The number of shooting points in the workspace is equal to the number of positioning marks on the piece to be bonded, and there is a corresponding shooting point directly above each positioning mark, so that the camera can shoot the corresponding positioning mark at the shooting point.

[0050] For ease of understanding, one of the parts to be bonded in the present invention is a standard part, and the structure of the standard part is exactly the same as that of the other parts to be bonded. There is no essential difference between the two, except that the former is used in the following steps S100-S300, and the latter is applied to step S400.

[0051] The position determination method of the present invention comprises the steps of:

[0052] S100: Place one of the parts to be bonded as a standard part at a placement position for parts to be bonded; collect image information of a corresponding positioning mark at a shooting point, and determine the standard pixel coordinates (x1, y1) of the positioning mark in the image information.

[0053] S200, move the marking mechanism so that it is located directly above the positioning mark, and determine the standard positioning coordinates (X1, Y1) of the marking mechanism on the bonding device. The position of the positioning mark of the standard part is (X1, Y1);

[0054] S300: Determine a conversion coefficient k between pixels in the image information and the spatial size of the fitting device.

[0055] Perform step S400 on each piece to be bonded:

[0056] S400. Place the parts to be bonded at the placement position of the parts to be bonded, and still collect the image information of the corresponding positioning mark at the shooting point, and determine the target pixel coordinates S'(x2, y2) of the positioning mark in the image information. Then the position coordinates S(X2, Y2) of the positioning mark of the bonding part on the bonding device are.

[0057] X2=X1+(x2-x1)*k;

[0058] Y2=Y1+(y2-y1)*k;

[0059] The two horizontal axes of the coordinate systems in the lamination device and the image information are respectively parallel.

[0060] In the present invention, the working space has a corresponding mechanical coordinate system, which is a three-dimensional coordinate system. The mechanical coordinate system has an X-axis, a Y-axis and a Z-axis, wherein the plane formed by the X-axis and the Y-axis is parallel to the horizontal plane, and the Z-axis is the vertical direction. The shooting point is a specific point on the mechanical coordinate system. After the standard part is placed in the position where the part to be bonded is placed, the positioning mark is located directly below the shooting point, so that the camera 3 located at the shooting point can shoot the positioning mark downward.

[0061] For example, the mechanical coordinates of the shooting point in the mechanical coordinate system are (Xp, Yp, Zp). After the standard part is placed in the position with the fitting part, it is assumed that the mechanical coordinates of the positioning mark in the mechanical coordinate system are (Xd, Yd, Zd), where Zd is the position of the standard part on the Z axis, Xd is close to Xp, and Yd is close to Yp, so that the shooting point is located directly above the positioning mark.

[0062] In step S100, the camera 3 photographs the positioning mark at the photographing point to obtain image information (to distinguish it from the image information generated by subsequent photographing of other parts to be bonded, the image information obtained by photographing the positioning mark of the standard part is referred to as "standard image information"). Since Xd is close to Xp and Yd is close to Yp, the image positioning mark (to distinguish it from the positioning marks on other parts to be bonded, the positioning mark in the standard image information is referred to as "image positioning mark") is basically located at the center of the standard image information. Therefore, in the standard image information, the image positioning mark can be clearly displayed in the standard image information, so that the image positioning mark can be identified with high precision in the standard image information; an image coordinate system corresponding to the standard image information is established. The image coordinate system is a two-dimensional coordinate system having an x-axis and a y-axis. In order to facilitate the subsequent conversion of pixel coordinates in the image coordinate system into mechanical coordinates of a mechanical coordinate system, it is preferred that the x-axis is parallel to the x-axis and the y-axis is parallel to the y-axis. Due to the establishment of the image coordinate system, the standard pixel coordinates (x1, y1) of the image positioning mark in the image coordinate system can be determined.

[0063] In step S200, the marking mechanism 2 is controlled to move within the workspace so that it is directly above the positioning mark of the standard component. At this time, recording the mechanical coordinates (X1, Y1) of the marking mechanism 2 in the mechanical coordinate system only requires determining its coordinates on the X and Y axes. These mechanical coordinates (X1, Y1) are recorded as the standard positioning coordinates (X1 is the aforementioned Xd, and Y1 is the aforementioned Yd). In the present invention, the positioning mark coordinates in the mechanical coordinate system are determined by moving the marking mechanism 2, which is more direct and accurate. This lays a solid foundation for the subsequent determination of the mechanical coordinates of the positioning marks of other components to be bonded, thereby improving the accuracy of the subsequent positioning of the positioning marks of other components to be bonded.

[0064] In addition, since the standard positioning coordinates and the standard pixel coordinates are both the positioning of the same positioning mark in different coordinate systems, a connection is established between the mechanical coordinate system and the image coordinate system, that is, the standard pixel coordinates (x1, y1) in the image coordinate system correspond to the standard positioning coordinates (X1, Y1) in the mechanical coordinate system.

[0065] In step S300, the image information is formed by individual pixels arranged in a matrix, and the horizontal arrangement direction of the pixels is parallel to the x-axis, and the vertical arrangement direction is parallel to the y-axis. Each pixel in the matrix is a square monochrome color block, so the component of the pixel coordinate on the x-axis is the number of pixel columns (integer) in the image information, and the component on the y-axis is the number of pixel rows (integer) in the image information, so as to determine the specific pixel position. The pixel pointed to by the aforementioned standard pixel coordinate (x1, y1) in the image information is the standard pixel, and the standard pixel corresponds to the standard positioning coordinate (X1, Y1).

[0066] Since photographing a standard component generates image information—that is, an objective representation of the component's top surface—and the dimensions of the component corresponding to each pixel on the X and Y axes are unknown, the dimensions of the component's top surface corresponding to each pixel can be determined by measurement (detailed below). This is the conversion factor k between the image coordinate system and the mechanical coordinate system. k represents the length of a single pixel on the X or Y axis. For example, a k of 0.01 means that the side length of a single pixel corresponds to 0.01 mm on the X axis and 0.01 mm on the Y axis. In this way, any pixel coordinate in the image information can be converted to mechanical coordinates.

[0067] For example, k = 0.01, standard pixel coordinates (150, 150), standard positioning coordinates (2000 mm, 2000 mm); assuming that pixel coordinates C (50, 50) are converted to mechanical coordinates C', the positive direction of the x-axis is consistent with the positive direction of the X-axis, and the positive direction of the y-axis is consistent with the positive direction of the Y-axis.

[0068] It can be determined that pixel coordinate C is offset by 100 pixels on the x-axis and 100 pixels on the y-axis compared to the standard pixel coordinates. Each pixel corresponds to 0.01mm in the mechanical coordinate system. In other words, mechanical coordinate C' is offset by 1mm on both the x-axis and y-axis compared to the standard positioning coordinates. Therefore, mechanical coordinate C' is (1999mm, 1999mm). In this way, based on the offset between any pixel coordinate in the image coordinate system and the standard pixel coordinate, the offset of its corresponding mechanical coordinate relative to the standard positioning coordinate can be determined, thereby determining its corresponding mechanical coordinate, achieving high-precision conversion of any pixel coordinate in the image coordinate system into mechanical coordinates.

[0069] See also Figure 3-Figure 5 In actual use, corresponding to step S400, at this time, the placement position of the piece to be bonded is vacant, and the piece to be bonded is placed in the placement position of the piece to be bonded. Although the piece to be bonded is exactly the same as the standard piece, when the piece to be bonded is placed in the placement position of the piece to be bonded, due to the existence of placement error, there is a certain difference between the placement position of the piece to be bonded and the placement position of the standard piece. That is to say, the target positioning coordinates S (X2, Y2) of the positioning mark on the piece to be bonded in the mechanical coordinate system and the standard positioning coordinates (X1, Y1) are very likely to be different. Therefore, it is necessary to determine the coordinates S of the positioning mark on the piece to be bonded in the mechanical coordinate system. Specifically, the target image information is obtained by photographing the positioning mark on the workpiece to be bonded directly below it at the shooting point through the photographing device 3 (to distinguish it from the aforementioned standard image information, the image information obtained by photographing the workpiece to be bonded is called the target image information). The target image information and the standard image information are both photographed by the same photographing device 3, at the same shooting point, for the workpiece to be bonded at the same placement position. The difference is that the former is the workpiece to be bonded, and the latter is the standard workpiece. Therefore, the image coordinate systems of the target image information and the standard image information are completely consistent; the position of the positioning mark in the target image information is identified, and the target pixel coordinates S'(x2, y2) of the positioning mark in the target image information in the image coordinate system are determined. Then, according to the target pixel coordinates S'(x2, y2) and the standard pixel coordinates (x1, y1), the offsets of the target pixel coordinates and the standard pixel coordinates on the x-axis and y-axis are determined (see Figure 3 ), then combined with the conversion coefficient k, the offset of the target positioning coordinates relative to the standard positioning coordinates is obtained. Based on the standard positioning coordinates, the target positioning coordinates S(X2, Y2) can be obtained. In this way, simply by photographing the positioning mark on the part to be bonded using the camera 3 at the shooting point, the target positioning coordinates S can be determined. The specific process for determining the target positioning coordinates S can be found in the previous two paragraphs and will not be repeated here.

[0070] It should be emphasized that in the present invention, the placement position of the parts to be bonded can roughly position the parts to be bonded, that is, no matter which part to be bonded is placed in the placement position of the parts to be bonded, in the mechanical coordinate system, the target positioning coordinates of the positioning mark are near the standard positioning coordinates (the deviations on the X-axis and Y-axis are both within 4mm). The present application amplifies such a small deviation to the pixel level, determines the specific deviation value by the number of pixels, and thus determines the target positioning coordinates, thereby improving the positioning accuracy of the positioning mark on the part to be bonded, and facilitating the subsequent high-precision bonding of the backlight sheet and the segment code screen.

[0071] Moreover, in the present invention, when the photographic device 3 shoots the positioning mark, the photographic device 3 is located at the corresponding shooting point, so that the photographic device 3 is located directly above the positioning mark, so that in the obtained image information, the image positioning mark is basically located in the middle of the image information, which improves the recognition of the image positioning mark on the one hand. In addition, the degree of deformation of the partial information located in the middle area of the image information is very small (the size of the mechanical coordinate system corresponding to the partial pixels in the middle area is consistent, and the size of the mechanical coordinate system corresponding to the partial pixels farther away from the middle area tends to become larger. The middle area is circular or rectangular, and the center point of the middle area is consistent with the center point of the image information. The area of the middle area is 0.05-0.15 of the area of the image information). In this way, no matter which part to be bonded is photographed, the image positioning mark in the obtained image information is located in the middle area of the image information. In this way, the corresponding target positioning coordinates can be obtained with high precision, thereby improving the positioning accuracy of the positioning mark on the part to be bonded in the mechanical coordinate system.

[0072] In the present invention, a corresponding fixed shooting point is set directly above each positioning mark. Since the position of the photographic equipment is the same when photographing the same positioning mark of each identical part to be bonded, it is only necessary to determine the standard pixel coordinates of the positioning mark on the standard part in the image information and the absolute coordinates of the positioning mark in the mechanical coordinate system, as well as the conversion relationship between the spatial size of the bonding equipment and the number of pixels in the image information. Subsequently, for the part to be bonded, it is only necessary to determine the target pixel coordinates of the positioning mark thereon in the image information, that is, to determine its target positioning coordinates in the mechanical coordinate system. In this way, by determining the absolute positions of the corresponding positioning marks on the backlight sheet and the segment code screen, the backlight sheet can be moved to the segment code screen by mechanical equipment such as a robot arm to achieve precise alignment. This method of determining the position can avoid the problems of low yield, low bonding efficiency and damage to the operator's eyes caused by manual alignment; and there is no need to record the position of the photographic equipment in the absolute coordinate system each time, which can avoid the final conversion error caused by the uncertainty of the photographic equipment's shooting position each time; at the same time, this method is used to capture images of each positioning mark separately, rather than capturing multiple positioning marks at the same time in one picture. In this way, a small range of shooting is used to enable the positioning mark to be located in the center area of the image information, thereby minimizing the positioning error caused by shooting angle, image distortion, etc., and further improving the position accuracy of the positioning mark in the bonding equipment.

[0073] The positioning mark is a circular structure; the marking mechanism 2 includes a positioning rod, which is vertically arranged. When the marking mechanism 2 moves in the workspace, the positioning rod is always in a vertical state.

[0074] In step S100 , the standard pixel coordinates are the coordinates of the center point of the positioning mark in the image information in the image coordinate system.

[0075] In step S200, the marking mechanism 2 is adjusted so that the axis of the positioning rod is located directly above the center point of the photographed positioning mark. At this time, the coordinates of the positioning rod on the bonding device (mechanical coordinate system) are the standard positioning coordinates (X1, Y1).

[0076] In standard image information, the image positioning mark occupies a certain number of pixels, but not all pixel coordinates can be used as standard pixel coordinates. When the positioning mark is a hollow circle structure, the pixel coordinates corresponding to the pixel where the center of the image positioning mark is located are used as standard pixel coordinates.

[0077] In step S200, since the axis of the positioning rod is located directly above the center point of the positioning mark, the coordinate of the axis of the positioning rod on the X-axis is the same as the coordinate of the positioning mark on the X-axis, and the coordinate of the axis of the positioning rod on the Y-axis is the same as the coordinate of the positioning mark on the Y-axis. Therefore, the standard positioning coordinates (X1, Y1) of the positioning mark can be determined by the coordinates of the positioning rod in the mechanical coordinate system.

[0078] Of course, the positioning mark may also be a cross-shaped structure, in which case the cross intersection is positioned to determine the standard pixel coordinates and the standard positioning coordinates.

[0079] When adjusting the marking mechanism 2, the marking mechanism 2 can be controlled to move on the Z axis first, so that the lower end of the positioning rod is close to the positioning mark in the vertical direction, and then the positioning rod is moved to directly above the positioning mark. This can improve the positioning accuracy of the positioning rod on the positioning mark.

[0080] In another embodiment, the lower end of the positioning rod is in a conical structure.

[0081] In step S100 , the standard pixel coordinates are the coordinates of the positioning mark in the image information.

[0082] In step S200 , the marking mechanism is adjusted so that the tip of the conical structure is located directly above the center point of the positioning mark.

[0083] By adjusting the marking mechanism so that the tip of the positioning rod is located directly above the center point of the positioning mark, the coordinates of the positioning rod on the bonding device (mechanical coordinate system) are the standard positioning coordinates (X1, Y1).

[0084] A light source is provided on the lower side of the position where the parts to be bonded are placed; the positioning mark is a hollow circle structure, and the positioning mark is a light-transmitting area set on the parts to be bonded; the positioning rod is a cylindrical structure, and its outer diameter is equal to the diameter of the hollow circle structure.

[0085] In step S200, the marking mechanism is adjusted so that the lower end of the positioning rod blocks the light transmitted through the hollow circular structure. At this time, the coordinates of the positioning rod on the bonding device are the standard positioning coordinates.

[0086] The light source shines upward from below, and the light hits the lower side of the part to be bonded and is emitted from the light-transmitting area. The light emitted outside the light-transmitting area is weaker. Therefore, in the image information, the captured image positioning mark is a bright spot with the same shape as the positioning mark, so that the standard pixel coordinates can be determined.

[0087] In step S200, when the positioning rod moves to the top of the positioning mark, all the light passing through the positioning mark will hit the lower end face of the positioning rod. Therefore, it is possible to determine whether the lower end face of the positioning rod is completely illuminated by the light and whether the positioning rod has moved to the top of the positioning mark, thereby accurately obtaining the standard positioning coordinates.

[0088] Of course, the positioning mark can also be a colored mark provided on the piece to be bonded, and it only needs to be able to be effectively identified in the image information and the image positioning mark can be effectively positioned.

[0089] Furthermore, when determining the target positioning coordinates, the marking mechanism 2 can be moved repeatedly so that the lower end of the positioning rod is located directly above the positioning mark, and the mechanical coordinates of the positioning rod are recorded each time, and then the average is taken, which is (X1, Y1).

[0090] For example, move the marking mechanism 2 for the first time so that the lower end of the positioning rod is located directly above the positioning mark (directly above the center of the positioning mark, or directly above the cross intersection), and record the coordinates of the positioning rod in the mechanical coordinate system at this time (X01, Y01); repeat this 5 times to obtain (X02, Y02), (X03, Y03), (X04, Y04) and (X05, Y05) respectively.

[0091] in,

[0092] By repeatedly measuring the mechanical coordinates of the positioning mark and averaging them, the accuracy of the standard positioning coordinates can be improved.

[0093] The number of repetitions can be 5 times, 10 times, 15 times, 18 times or 20 times, etc.

[0094] Regarding step S400, in a preferred embodiment, step S300 includes the following steps:

[0095] S310. Place a ruler on the placement platform 1, with the length direction of the ruler parallel to the x-axis or the y-axis of the image information, and at least part of the ruler located directly below the shooting point; the photographic device 3 photographs the ruler directly below it at the shooting point to obtain ruler image information.

[0096] S320 , obtaining the number of pixels A occupied by the preset ruler length B in the ruler image information, and obtaining k=B / A.

[0097] The ruler has a mark of preset length, for example, a length mark of 10 mm. The ruler is placed on the placement platform 1 and is located directly below the shooting point. The photographic device 3 shoots the ruler at the shooting point to obtain ruler image information, and then identifies the number of pixels occupied by the 10 mm length mark in the ruler image information. For example, if it occupies 1000 pixels, it can be obtained that 1000 pixels in the image information correspond to a length of 10 mm, so k is 0.01.

[0098] Preferably, in the ruler image information, the pixels occupied by the preset length of the ruler are located in the middle area of the ruler image information, so that k corresponds to the conversion coefficient between the two coordinate systems in the middle area of the image information, so that the target positioning coordinates of the positioning mark of the part to be bonded on the mechanical coordinate system can be obtained more accurately later.

[0099] Of course, in the embodiment where the positioning mark is a hollow circle structure, the diameter of the positioning mark is obtained in advance (corresponding to the aforementioned preset length B), and then the number of pixels A occupied by the graphic positioning mark on the x-axis or y-axis is obtained in the standard image information, so that the conversion coefficient k can also be obtained.

[0100] The ratio of the preset length B to the maximum length of the positioning mark in the length direction is 1 to 3, for example, 1, 2 or 3. This allows the preset length B of the ruler to highlight the center area of the ruler in the ruler image information, thereby improving the accuracy of k.

[0101] For the parts to be bonded, if there is only one positioning mark on the parts to be bonded, only the coordinates of a point on the parts to be bonded in the mechanical coordinate system can be determined. At this time, the parts to be bonded can be placed at any angle around the positioning mark, so it is still impossible to accurately determine the position of the parts to be bonded in the mechanical coordinate system.

[0102] There are two positioning marks on the parts to be bonded, and there are multiple placement positions for the parts to be bonded, some of which are placement positions for segment code screens and some of which are placement positions for backlight sheets. The segment code screen is placed at the segment code screen placement position and the backlight sheet is placed at the backlight sheet placement position. A corresponding shooting point is provided above each positioning mark.

[0103] The positions of the positioning marks of the parts to be bonded located at each placement position of the parts to be bonded are determined through steps S100 to S400.

[0104] The parts to be bonded have two positioning marks. When the parts to be bonded are placed in the bonding position, there is a corresponding shooting point directly above each positioning mark. For each positioning mark, the corresponding image coordinate system and mechanical coordinate system conversion relationship is established according to the aforementioned steps S100-S300.

[0105] For example, the two positioning marks on the part to be bonded (standard part) are the first positioning mark and the second positioning mark respectively. Correspondingly, a first shooting point and a second shooting point are provided in the working space. When the part to be bonded is placed in the placement position of the part to be bonded, the first shooting point is located directly above the first positioning mark, and the second shooting point is located directly above the second positioning mark.

[0106] The photographic device 3 photographs the first positioning mark at the first shooting point to obtain the first standard image information, establishes the first image coordinate system, and obtains the first standard pixel coordinates of the first image positioning mark (corresponding to the first positioning mark) in the first standard image information in the first image coordinate system; then the marking mechanism 2 is moved to determine the first standard positioning coordinates of the first positioning mark in the mechanical coordinate system; and then the conversion coefficient k1 between the first image coordinate system and the mechanical coordinate system is determined, so that any pixel coordinates in the first image coordinate system can be converted into mechanical coordinates.

[0107] The photographic device 3 photographs the second positioning mark at the second shooting point to obtain second standard image information, and establishes a second image coordinate system to obtain the second standard pixel coordinates of the second image positioning mark (corresponding to the second positioning mark) in the second standard image information in the second image coordinate system; then the marking mechanism 2 is moved to determine the second standard positioning coordinates of the second positioning mark in the mechanical coordinate system; and then the conversion coefficient k2 between the second image coordinate system and the mechanical coordinate system is determined, so that any pixel coordinates in the second image coordinate system can be converted into mechanical coordinates.

[0108] Each positioning mark has a corresponding shooting point, so that each positioning mark has corresponding image information (the aforementioned first standard image information and second standard image information), and establishes a corresponding image coordinate system, and determines the corresponding standard pixel coordinates in the corresponding image coordinate system, thereby improving the positioning accuracy of each positioning mark in the corresponding image coordinate system; that is, in the present invention, one shooting point corresponds to one image coordinate system and also corresponds to one photographed positioning mark, so that the corresponding image positioning mark is located in the middle area of the image information, thereby improving the positioning accuracy of each image positioning mark in the corresponding image coordinate system.

[0109] In step S400, when determining the position of the part to be bonded, after the part to be bonded is placed at the part placement position, the photographic device 3 photographs the first positioning mark on the part to be bonded at a first shooting point to obtain first target image information, and determines the first target pixel coordinates of the positioning mark in the first image coordinate system, and then determines the first target positioning coordinates of the first positioning mark on the part to be bonded in the mechanical coordinate system based on the first standard pixel coordinates, the conversion coefficient k1 and the first standard positioning coordinates; similarly, the photographic device 3 photographs the second positioning mark on the part to be bonded at a second shooting point to obtain second target image information, and determines the second target pixel coordinates of the positioning mark in the second image coordinate system, and then determines the second target positioning coordinates of the second positioning mark on the part to be bonded in the mechanical coordinate system based on the second standard pixel coordinates, the conversion coefficient k2 and the second standard positioning coordinates. In this way, the coordinates of the two positioning marks on the part to be bonded in the mechanical coordinate system can be determined, thereby determining the placement coordinates of the part to be bonded in the mechanical coordinate system (for example, the first target coordinates, the second target coordinates or the coordinates of the preset point on the part to be bonded) and the placement angle (for example, the angle between the line between the first target coordinates and the second target coordinates relative to the X-axis or Y-axis).

[0110] In the present invention, a placement position for a segment code screen and a placement position for a backlight are provided on the placement platform 1, two backlight positioning marks are provided on the backlight, and two corresponding segment code screen positioning marks are also provided on the segment code screen. According to the aforementioned method, the placement coordinates and placement angle of the backlight are determined respectively, and the placement coordinates and placement angle of the segment code screen are determined. Then, the backlight can be grabbed with high precision, and the angle of the backlight can be adjusted to be consistent with the placement angle of the segment code screen. Then, the backlight is moved to the placement coordinates of the segment code screen and fits with the segment code screen, thereby achieving high-precision fitting of the backlight and the segment code screen.

[0111] Since the shooting point in the present invention corresponds to an image coordinate system, the conversion coefficient k between each image coordinate system and the mechanical coordinate system is determined separately to improve the accuracy of the subsequent determination of the target positioning coordinates.

[0112] Of course, if the heights of all shooting points are consistent (the data on the Z axis are the same) and the heights of each positioning coordinate are also consistent, then the conversion coefficient k between each image coordinate system and the mechanical coordinate system is basically equal, so it is only necessary to determine the conversion coefficient k once in step S300, and the conversion coefficient k is used as the conversion coefficient between each image coordinate system and the mechanical coordinate system.

[0113] Furthermore, the placement platform 1 is provided with a segment code screen positioning block and a backlight sheet positioning block, the segment code screen positioning blocks enclose the segment code screen placement position, and the backlight sheet positioning blocks enclose the backlight sheet placement position.

[0114] When placing the segment code screen in the segment code screen placement position, the segment code screen can be roughly positioned through the segment code screen positioning block so that several positioning marks on the segment code screen are located directly below the corresponding shooting points; when placing the backlight sheet in the backlight sheet placement position, the backlight sheet can be roughly positioned through the backlight sheet positioning block so that several positioning marks on the backlight sheet are located directly below the corresponding shooting points.

[0115] In some embodiments, the backlight sheet is rectangular, and the backlight sheet positioning block only needs to position two adjacent sides of the backlight sheet to achieve coarse positioning of the backlight sheet; the segment code screen is rectangular, and the segment code screen positioning block only needs to position two adjacent sides of the segment code screen to achieve coarse positioning of the segment code screen.

[0116] There is one photographic device 3, and the photographic device 3 is connected to the marking mechanism 2 so that the photographic device 3 can be moved to each shooting point to collect image information; at each shooting point, the optical axis of the photographic device 3 is located near or past the shooting point.

[0117] Each shooting point has corresponding shooting coordinates in the mechanical coordinate system. These shooting coordinates are preset. The photographic device 3 is connected to the marking mechanism 2 so that the photographic device 3 can also move in the working space. When a certain positioning mark needs to be photographed, the photographic device 3 is moved to the corresponding shooting coordinates. At this time, the photographic device 3 is located at the corresponding shooting point.

[0118] Of course, the photographic device 3 may not be connected to the marking mechanism 2, but may be independently movable in the working space, so that the photographic device 3 can be moved to various shooting points.

[0119] In another embodiment, each shooting point is fixedly provided with a camera 3. When a positioning mark needs to be photographed, the camera 3 at the corresponding shooting point can be used to shoot the mark.

[0120] See also Figure 2 The present invention also provides a bonding device that can implement the aforementioned position determination method. The device includes a workspace, in which a three-axis moving mechanism, a marking mechanism 2, a photographic device 3 and a placement platform 1 are provided.

[0121] The placing platform 1 is arranged at the lower part of the working space, and a placement position for the parts to be bonded is provided on the placing platform 1.

[0122] The marking mechanism 2 is installed on the three-axis moving mechanism so as to be driven to move in the working space by the three-axis moving mechanism.

[0123] Shooting points are set in the working space, and the camera device 3 can reach each shooting point.

[0124] In one embodiment, a shooting point is provided in the working space, and the camera device 3 is disposed at the shooting point.

[0125] The camera device 3 is fixed at the shooting point to shoot the positioning mark on the piece to be bonded placed at the position of the piece to be bonded. The specific working process has been described in the above-mentioned position determination method and will not be repeated here.

[0126] In another embodiment, the number of the marking mechanism 2 and the camera device 3 are both one and connected together. The two are installed on a three-axis moving mechanism so as to be driven to move in the working space by the three-axis moving mechanism.

[0127] In the present invention, a corresponding fixed shooting point is set directly above each positioning mark. Since the position of the photographic equipment is the same when photographing the same positioning mark of each identical part to be bonded, it is only necessary to determine the standard pixel coordinates of the positioning mark on the standard part in the image information and the absolute coordinates of the positioning mark on the bonding equipment, as well as the conversion relationship between the spatial size of the bonding equipment and the number of pixels in the image information. Subsequently, for the part to be bonded, it is only necessary to determine the target pixel coordinates of the positioning mark thereon in the image information to determine its absolute coordinates on the bonding equipment. In this way, by determining the absolute positions of the corresponding positioning marks on the backlight sheet and the segment code screen, the backlight sheet can be moved to the segment code screen by mechanical equipment such as a robot to achieve precise alignment. This method of determining the position can avoid the problems of low yield, low bonding efficiency and damage to the operator's eyes caused by manual alignment; and there is no need to record the position of the photographic equipment in the absolute coordinate system each time, which can avoid the final conversion error caused by the uncertainty of the photographic equipment's shooting position each time; at the same time, this method is used to capture images of each positioning mark separately, rather than capturing multiple positioning marks at the same time in one picture. In this way, a small range of shooting is used to enable the positioning mark to be located in the center area of the image information, thereby minimizing the positioning error caused by shooting angle, image distortion, etc., and further improving the position accuracy of the positioning mark in the bonding equipment.

[0128] It should be noted that the use of step numbers (letters or numbers) to refer to certain specific method steps in the present invention is solely for the purpose of descriptive convenience and brevity, and is in no way intended to limit the order of these method steps. Those skilled in the art will appreciate that the order of the relevant method steps is determined by the technology itself and should not be unduly limited by the presence of step numbers. Those skilled in the art can determine various permissible and reasonable step orders based on the technology itself.

[0129] Those skilled in the art will appreciate that, provided there is no conflict, the above preferred solutions can be freely combined and superimposed.

[0130] It should be understood that the above-mentioned embodiments are merely illustrative and non-restrictive. Without departing from the basic principles of the present invention, various obvious or equivalent modifications or substitutions that can be made by those skilled in the art to the above-mentioned details will be included in the scope of the claims of the present invention.

Claims

1. A method for determining the position of a component to be bonded in a bonding device, for use in aligning a segmented screen and a backlight sheet when bonding, wherein the component to be bonded comprises a segmented screen and a backlight sheet, both of which are provided with corresponding positioning marks; characterized in that: The bonding device is provided with a placement position for the piece to be bonded, a movable marking mechanism and a relatively fixed shooting point. When the piece to be bonded is placed at the placement position for the piece to be bonded, there is a corresponding shooting point directly above each positioning mark. The position determination method comprises the steps of: S100, placing one of the parts to be bonded as a standard part at the placement position of the parts to be bonded; collecting image information of the corresponding positioning mark at the shooting point, and determining the standard pixel coordinates (x1, y1) of the positioning mark in the image information; S200, moving the marking mechanism so that it is located directly above the positioning mark, and determining the standard positioning coordinates (X1, Y1) of the marking mechanism on the laminating device. The position of the positioning mark of the standard component is (X1, Y1); S300, determining a conversion coefficient k between pixels in the image information and the spatial size of the fitting device; Perform step S400 on each piece to be bonded: S400, placing the to-be-bonded parts at the to-be-bonded parts placement position, still capturing the image information of the corresponding positioning mark at the shooting point, and determining the target pixel coordinates S'(x2, y2) of the positioning mark in the image information. The position coordinates S(x2, y2) of the positioning mark of the to-be-bonded parts on the bonding device are: X2=X1+(x2-x1)*k; Y2=Y1+(y2-y1)*k; wherein the two horizontal axes of the coordinate system of the laminating device and the image information are respectively parallel; The position of each positioning mark of the piece to be bonded located at each position of the piece to be bonded is determined by the method of steps S100 to S400; Wherein, the step S300 includes the steps of: S310, placing a ruler at the position where the pieces to be bonded are placed, with the length of the ruler parallel to the x-axis or y-axis of the image information, and at least a portion of the ruler located directly below the shooting point; and collecting ruler image information of the ruler at the shooting point; S320 , obtaining the number of pixels A occupied by the preset length B of the ruler in the ruler image information, and obtaining k=B / A.

2. The position determination method according to claim 1, wherein: The marking mechanism includes a positioning rod, which is vertically arranged; In the step S100, the standard pixel coordinates are the coordinates of the center point of the positioning mark in the image information; In step S200, the marking mechanism is adjusted so that the axis of the positioning rod is located directly above the center point of the positioning mark, and the coordinates of the positioning rod on the bonding device are the standard positioning coordinates.

3. The position determination method according to claim 2, characterized in that: The lower end of the positioning rod is in a conical structure; In the step S100, the standard pixel coordinates are the coordinates of the center point of the positioning mark in the image information; In step S200, the marking mechanism is adjusted so that the tip of the conical structure is located directly above the center point of the positioning mark.

4. The method for determining a position according to claim 3, wherein: The positioning mark is a cross-shaped structure or a hollow circle structure.

5. The method for determining a position according to claim 2, wherein: A light source is provided on the lower side of the position where the workpiece to be bonded is placed; the positioning mark is a hollow circle structure, which is provided in the light-transmitting area on the workpiece to be bonded; the positioning rod is a cylindrical structure, and its outer diameter is equal to the diameter of the hollow circle structure; In step S200, the marking mechanism is adjusted so that the lower end of the positioning rod blocks the light transmitted through the hollow circular structure. At this time, the coordinates of the positioning rod on the bonding device are the standard positioning coordinates.

6. The position determination method according to any one of claims 1 to 5, characterized in that: The part to be bonded is provided with two positioning marks, and there are multiple placement positions for the part to be bonded, some of which are placement positions for segment code screens and some of which are placement positions for backlight sheets.

7. The position determination method according to claim 6, characterized in that: The bonding device also includes a photographic device, which is connected to the marking mechanism so as to collect the image information at each of the shooting points through the same photographic device; at each of the shooting points, the optical axis of the photographic device is located near or passes through the shooting point.

8. A laminating device, characterized in that: When the workpiece to be bonded is placed at a placement position for workpieces to be bonded, the position coordinates of the positioning mark on the workpiece to be bonded on the bonding device are determined using the position determination method according to any one of claims 1 to 7; the bonding device includes a workspace in which a three-axis moving mechanism, a marking mechanism, a camera, and a placement platform are provided; The placing platform is arranged at the lower part of the working space, and a placement position for the parts to be bonded is provided on the placing platform; The marking mechanism is mounted on the three-axis moving mechanism so as to be driven to move within the working space by the three-axis moving mechanism; Shooting points are arranged in the working space, and the photographic equipment can reach each of the shooting points.

Images