OLED display screen chip mounter

Abstract

The invention provides an OLED display screen chip mounter, and relates to the field of screen chip mounting equipment. The OLED display screen chip mounter comprises a main machine body, a feeding mechanism, a positioning mechanism, a mounting mechanism, a detection mechanism and a control system, the positioning mechanism, the mounting mechanism and the control system are installed on the main machine body, and the positioning mechanism comprises a first visual positioning assembly, a laser positioning assembly and a second visual positioning assembly. The mounting mechanism comprises a six-axis mechanical arm, the six-axis mechanical arm is mounted on a working table plate of the main machine body, and four vacuum suction nozzles are mounted on the six-axis mechanical arm. According to the OLED display screen chip mounter, the problems that an existing OLED display screen chip mounter is low in positioning precision, surface impurities of workpieces affect the mounting quality, the detection dimension is single, and fault response lags behind are solved, and meanwhile deformation-free adsorption and efficient mounting of a flexible OLED screen are achieved.

Description

Technical Field

[0001] This invention relates to the field of screen mounting equipment, specifically an OLED display mounting machine. Background Technology

[0002] OLED liquid crystal displays have advantages such as self-illumination, fast response speed, high contrast, and wide viewing angle, and are widely used in electronic devices such as smartphones, tablets, and televisions. In the manufacturing process of OLED displays, the mounting process is one of the key steps, requiring the precise attachment of the OLED screen to the substrate. The mounting accuracy directly affects the display effect and lifespan of the product. Existing OLED mounting machines have the following shortcomings: Insufficient positioning accuracy: Most devices only use a single vision positioning method, which is affected by factors such as light and reflection on the workpiece surface, resulting in large positioning deviations and easily leading to problems such as placement misalignment and air bubbles. Poor compatibility: The existing equipment has a fixed mounting mechanism structure, which makes it difficult to adapt to OLED displays of different sizes and thicknesses. When changing product models, the mechanical structure needs to be adjusted frequently, which is time-consuming and labor-intensive. Low placement efficiency: The placement process lacks a real-time detection and feedback mechanism, requiring offline detection after placement. If defective products are found, rework is necessary, which affects production efficiency. Therefore, those skilled in the art propose an OLED display chip mounter with high positioning accuracy, comprehensive workpiece protection, thorough inspection, and rapid response to address the shortcomings of the prior art. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides an OLED display chip mounter that solves the problems of low positioning accuracy, surface impurities affecting mounting quality, limited detection dimensions, and delayed fault response in existing OLED display chip mounters. At the same time, it achieves deformation-free adsorption and efficient mounting of flexible OLED screens.

[0004] To achieve the above objectives, the present invention provides the following technical solution: An OLED display chip mounter includes a main body, a feeding mechanism, a positioning mechanism, a mounting mechanism, a detection mechanism, and a control system. The main body is equipped with the positioning mechanism, the mounting mechanism, and the control system. The positioning mechanism includes a first vision positioning component, a laser positioning component, and a second vision positioning component. The mounting mechanism includes a six-axis robotic arm mounted on the worktable of the main body. Four vacuum nozzles are mounted on the six-axis robotic arm. The vision positioning instrument of the second vision positioning component is installed in the middle of the four vacuum nozzles of the six-axis robotic arm. The six-axis robotic arm and the four vacuum nozzles constitute the mounting mechanism. The feeding mechanism includes a screen substrate conveyor and a screen conveyor. The main body of the detection mechanism is a detection module, which includes a visual inspection camera, a displacement sensor, and an alarm. The main body of the control system is a CNC host, which controls the screen substrate conveyor, the screen conveyor, the mounting module, and the detection module. Through the above technical solution, by linking the control system with each actuator (feeding, positioning, mounting, and testing), the entire OLED mounting process is automated, eliminating the need for manual intervention and improving work efficiency. At the same time, the real-time data processing capability of the CNC host ensures the accuracy and synchronization of each process.

[0005] Furthermore, the feeding mechanism is used to transport the OLED liquid crystal display screen and the substrate to be mounted. The screen conveyor is located on one side of the six-axis robotic arm, and the screen substrate conveyor is placed in the middle of the worktable of the main body, directly below the first vision positioning component and the laser positioning component. By using the above technical solution, the screen conveyor and the screen substrate conveyor are arranged in separate sections, which avoids the risk of collision caused by the intersection of workpiece conveying paths. At the same time, the screen substrate conveyor is precisely aligned with the positioning mechanism directly below, so there is no need to adjust the posture of the workpiece after it is conveyed into place, saving time for the subsequent precision positioning process.

[0006] Furthermore, the positioning mechanism is used to calibrate the position of the OLED liquid crystal display screen and the substrate to be mounted, the industrial camera of the second vision positioning component is used to photograph the OLED screen on the screen conveyor, and the image processing module of the CNC host is used to analyze and process the image information, obtain the position deviation data, and then control the four vacuum nozzles of the six-axis robotic arm to be fixed at the four corners of the OLED screen to adsorb and fix the OLED screen. Through the above technical solution, the main body of the second vision positioning component is a 10-megapixel camera with a frame rate of 60fps, which can accurately identify the reference marks at the four corners of the OLED screen. Combined with the image processing of the CNC host, the deviation data calculation error is <0.003mm. When the vacuum nozzles at the four corners adsorb, the screen is subjected to uniform force. Compared with traditional center adsorption, it effectively avoids wrinkles on the flexible screen and has higher adsorption stability.

[0007] Furthermore, when the display substrate on the screen substrate conveyor is conveyed to the area directly below the first vision positioning component, the industrial camera of the first vision positioning component is used to position the display substrate, the laser emitter of the laser positioning component emits a laser beam, and the laser receiver receives the laser signal reflected by the edge of the workpiece to accurately position the edge coordinates of the workpiece. The CNC host controls the six-axis robotic arm to attach and install the OLED display. Through the above technical solution, dual calibration is adopted. The first vision positioning component realizes the initial positioning of the substrate, and the laser positioning component scans the edge of the substrate. The edge coordinate positioning accuracy reaches ±0.005mm. The two work together to eliminate the reflection interference of single vision positioning. The CNC host controls the six-axis robotic arm to mount according to the positioning data. The final mounting offset is ≤±0.01mm, which meets the requirements of narrow bezel OLED.

[0008] Furthermore, the visual inspection camera of the detection module is used to capture images of the finished OLED display after mounting to detect the mounting offset; the displacement sensor is used to detect the bonding gap between the OLED liquid crystal display and the substrate to be mounted; and the alarm is used to issue an alarm signal when the equipment malfunctions or the mounting is unqualified. Through the above technical solution, the visual inspection camera can detect the mounting offset with an accuracy of ±0.002mm, and the displacement sensor can monitor the bonding gap in real time, realizing dual detection of offset and gap; when an out-of-tolerance error or equipment transmission failure is detected, the alarm is triggered and the machine is stopped.

[0009] Furthermore, during the positioning process, the first and second visual positioning components first perform algorithmic preprocessing on the image, first converting the image to grayscale and then using Gaussian filtering to eliminate high-frequency noise in the acquired image: ; in, This represents the offset of a pixel within the filter template relative to the center. Given a Gaussian standard deviation, the pixel values ​​of the filtered image are: ; Where K is a template size setting constant; After removing high-frequency noise, the image is subjected to reference feature extraction using the cross-reference standard method to locate core marker points. A corner detection template matching combination algorithm is then used to identify the marker feature points. The feature point response function is as follows: ; in, , For local windows, For pixel gradient, For empirical coefficients, when A value greater than the maximum response value is identified as a corner point and denoted as . These are the pixel coordinates of the image; After determining the core location, template matching verification is performed. A standard template with a pre-stored crosshair reference point and pixel size is used. The normalized cross-correlation coefficient between the detected corner regions and the template is calculated to exclude spurious feature points. The formula is as follows: ; in, As a standard template, To detect the region image, The average grayscale value of the template area. The grayscale mean of the detection area, when When a point is identified as a valid reference marker, the geometric centers of its four corner points are taken as the image coordinates of the reference marker.

[0010] Finally, the image coordinates are converted to real-world coordinates, and camera distortion is calibrated. The radial distortion correction formula is: ; ; in, Let these be the coordinates of the camera's principal point. The radial distortion coefficient is a constant; The distance from the pixel to the principal point; By transforming the matrix Corrected image coordinates Convert to real coordinates The coordinate transformation formula is: ; Where the Z-direction is fixed, the average thickness of the workpiece is taken. For camera focal length, The world coordinates of the preset reference marker are the distance from the workpiece to the camera. The actual detection coordinates are ,but: Translational deviation in the X direction: Translational deviation in the Y direction: : Rotational deviation: ; in, The rotation angle is the preset reference mark; Through the above technical solutions, the high-frequency noise removal rate of the image is over 95% after Gaussian filtering preprocessing, avoiding interference from false feature points. The feature point recognition accuracy of corner detection and template matching combined with the camera distortion calibration is ≥99.8%. After camera distortion calibration, the distortion error is reduced from 0.015mm to below 0.003mm. Finally, the error of converting image coordinates to real coordinates is <0.004mm, providing algorithmic support for positioning accuracy and ensuring no accuracy loss in the visual positioning process.

[0011] Furthermore, during the laser positioning process, the laser positioning component precisely detects the edges of the OLED display screen and the display substrate to determine the position of the edges in the laser scanning direction. It then collects the laser beam emitted by the laser emitter and scans perpendicular to the workpiece edge. After reflection from the workpiece edge, the laser forms a continuous light spot on the receiver, converting the light signal into a grayscale signal. The scan time corresponds to the CCD pixel column number, and then the grayscale signal is smoothed using a moving average filter. The calculation formula is as follows: ; in For window size, the difference formula is: Edge pixel position: ; Among them, it must meet the following requirements. , It is twice the mean of the differential signal, thus eliminating noise interference; Determine the fixed geometric parameters of the laser emitter and receiver: The horizontal distance between the transmitter and the receiver is The laser emission angle is ; pixel spacing is The receiver reference pixel position is ; The horizontal distance from the edge of the workpiece to the transmitter The calculation is as follows: ; in Let the equivalent focal length of the laser receiver be denoted as , and the horizontal distance be denoted as : ; Combining the fixed coordinates of the laser emitter in the world coordinate system The world coordinates of the workpiece edge can be calculated as follows: ; Laser positioning requires measuring at four vertices of the workpiece edge and taking the average value as the final edge coordinates. Through the above technical solution, the moving average filtering eliminates more than 98% of noise interference by filtering out the fluctuation amplitude of the grayscale signal. Combined with geometric parameter calculation, the world coordinate error of the workpiece edge is <0.004mm. The average value processing of the four vertices further reduces random errors, and the final laser positioning accuracy reaches ±0.005mm. It achieves dual calibration in conjunction with visual positioning to ensure that the relative position deviation between the substrate and the screen is ≤0.008mm.

[0012] Furthermore, a cleaning vacuum cleaner is provided on both sides of the screen substrate conveyor on the main body. The cleaning vacuum cleaner is used to remove static electricity and dust from the surface of the OLED liquid crystal display screen and the substrate to be mounted. Through the above technical solutions, the cleaning and dust removal equipment can effectively adsorb and remove dust and charged particles in the air, thereby greatly improving the success rate of the mounting process.

[0013] This invention provides an OLED display chip mounter. It has the following advantages: 1. This invention provides an OLED display chip mounter. By adopting a collaborative calibration architecture of dual visual positioning and laser positioning in the positioning mechanism, combined with noise suppression, distortion calibration and precise coordinate transformation at the algorithm level, high-precision positioning of OLED screen and substrate is achieved. The overall positioning accuracy reaches ±0.005mm, which effectively solves the defects of existing equipment's single visual positioning which is affected by reflection and wrinkles, and meets the mounting accuracy requirements of flexible and narrow-bezel OLEDs.

[0014] 2. This invention provides an OLED display chip mounter with enhanced compatibility. The screen substrate conveyor and the screen conveyor are respectively set at both ends of the six-axis robotic arm of the mounting module, making it easier to pick up and mount the OLED screen. At the same time, a four-corner vacuum nozzle is used to adsorb the OLED screen, avoiding deformation of the flexible panel. Furthermore, by integrating a cleaning vacuum cleaner into the feeding path, static electricity and dust on the workpiece surface are removed simultaneously, ensuring the quality of the workpiece before mounting from both the workpiece cleaning and adsorption protection dimensions. Attached Figure Description

[0015] Figure 1 This is a structural framework diagram of the OLED display chip mounter of the present invention; Figure 2 This is a top view of the overall structure of the OLED display chip mounter of the present invention; Figure 3 This is a front view of the overall structure of the main body of the OLED display chip mounter of the present invention; Figure 4 This is a schematic diagram of the detection module of the OLED display chip mounter of the present invention.

[0016] In the picture: 1. Main unit; 2. Screen substrate conveyor; 3. Screen conveyor; 4. Mounting module; 5. Detection module; 101. CNC main unit; 102. First vision positioning component; 103. Laser positioning component; 104. Cleaning vacuum cleaner; 401. Six-axis robotic arm; 402. Vacuum nozzle; 403. Second vision positioning component; 501. Vision inspection camera; 502. Alarm. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1: like Figure 1-4 As shown, this embodiment of the invention provides an OLED display chip mounter, including a main body 1, a feeding mechanism, a positioning mechanism, a mounting mechanism, a detection mechanism, and a control system. The main body 1 is equipped with the positioning mechanism, the mounting mechanism, and the control system. The positioning mechanism includes a first visual positioning component 102, a laser positioning component 103, and a second visual positioning component 403. The mounting mechanism includes a six-axis robotic arm 401, which is mounted on the worktable of the main body 1. Four vacuum nozzles 402 are mounted on the six-axis robotic arm 401. The visual positioning instrument of the second visual positioning component 403 is installed between the four vacuum nozzles 402 of the six-axis robotic arm 401. The six-axis robotic arm 401 and the four vacuum nozzles 402 constitute the mounting mechanism. The feeding mechanism includes a screen substrate conveyor 2 and a screen conveyor 3. The main body of the detection mechanism is the detection module 5, which includes a vision inspection camera 501, a displacement sensor, and an alarm 502. The main body of the control system is the CNC host 101, which controls the screen substrate conveyor 2, the screen conveyor 3, the mounting module 4, and the detection module 5. The feeding mechanism is used to transport the OLED liquid crystal display screen and the substrate to be mounted. The screen conveyor 3 is located on one side of the six-axis robotic arm 401. The screen substrate conveyor 2 is placed in the middle of the worktable of the host body 1, directly below the first vision positioning component 102 and the laser positioning component 103. The positioning mechanism is used to calibrate the position of the OLED liquid crystal display screen and the substrate to be mounted. The industrial camera of the second vision positioning component 403 is used to photograph the OLED screen on the screen conveyor 3. The image processing module of the CNC host 101 is used to analyze and process the image information, and after obtaining the position deviation data, it controls the four vacuum nozzles 402 of the six-axis robotic arm 401 to be fixed at the four corners of the OLED screen to adsorb and fix the OLED screen. When the display substrate on the screen substrate conveyor 2 is conveyed to the area directly below the first vision positioning component 102, the industrial camera of the first vision positioning component 102 is used to position the display substrate. The laser emitter of the laser positioning component 103 emits a laser beam, and the laser receiver receives the laser signal reflected by the edge of the workpiece to accurately position the edge coordinates of the workpiece. The CNC host 101 controls the six-axis robotic arm 401 to attach and install the OLED display. The vision inspection camera 501 of the detection module is used to take pictures of the finished product image after the OLED display is attached to detect the attachment offset. The displacement sensor is used to detect the bonding gap between the OLED liquid crystal display and the substrate to be attached. The alarm is used to issue an alarm signal when the equipment malfunctions or the attachment is unqualified. Cleaning vacuum cleaners 104 are provided on both sides of the main body of the screen substrate conveyor 2. The cleaning vacuum cleaners are used to remove static electricity and dust from the surface of the OLED liquid crystal display and the substrate to be attached.

[0019] Example 2: like Figure 1-4 As shown, this embodiment of the invention provides an OLED display chip mounter. During the positioning process, the first visual positioning component 102 and the second visual positioning component 403 first perform algorithmic preprocessing on the image. This involves converting the image to grayscale and using Gaussian filtering to eliminate high-frequency noise in the acquired image. ; in, This represents the offset of a pixel within the filter template relative to the center. Given a Gaussian standard deviation, the pixel values ​​of the filtered image are: ; Where K is a template size setting constant; After removing high-frequency noise, the image is subjected to reference feature extraction using the cross-reference standard method to locate core marker points. A corner detection template matching combination algorithm is then used to identify the marker feature points. The feature point response function is as follows: ; in, , For local windows, For pixel gradient, For empirical coefficients, when A value greater than the maximum response value is identified as a corner point and denoted as . These are the pixel coordinates of the image; After determining the core location, template matching verification is performed. A standard template with a pre-stored crosshair reference point and pixel size is used. The normalized cross-correlation coefficient between the detected corner regions and the template is calculated to exclude spurious feature points. The formula is as follows: ; in, As a standard template, To detect the region image, The average grayscale value of the template area. The grayscale mean of the detection area, when When a point is identified as a valid reference marker, the geometric centers of its four corner points are taken as the image coordinates of the reference marker.

[0020] Finally, the image coordinates are converted to real-world coordinates, and camera distortion is calibrated. The radial distortion correction formula is: ; ; in, Let these be the coordinates of the camera's principal point. The radial distortion coefficient is a constant; The distance from the pixel to the principal point; By transforming the matrix Corrected image coordinates Convert to real coordinates The coordinate transformation formula is: ; Where the Z-direction is fixed, the average thickness of the workpiece is taken. For camera focal length, The world coordinates of the preset reference marker are the distance from the workpiece to the camera. The actual detection coordinates are ,but: Translational deviation in the X direction: Translational deviation in the Y direction: : Rotational deviation: ; in, The rotation angle is the preset reference mark; During the laser positioning process, the laser positioning component precisely detects the edges of the OLED display and its substrate to determine their position along the laser scanning direction. A laser beam emitted from the laser emitter scans perpendicularly to the workpiece edge. After reflection from the workpiece edge, the laser forms a continuous spot on the receiver, converting the light signal into a grayscale signal. The scan time corresponds to the CCD pixel column number, and then the grayscale signal is smoothed using a moving average filter. The calculation formula is as follows: ; in For window size, the difference formula is: Edge pixel position: ; Among them, it must meet the following requirements. , It is twice the mean of the differential signal, thus eliminating noise interference; Determine the fixed geometric parameters of the laser emitter and receiver: The horizontal distance between the transmitter and the receiver is The laser emission angle is ; pixel spacing is The receiver reference pixel position is ; The horizontal distance from the edge of the workpiece to the transmitter The calculation is as follows: ; in Let the equivalent focal length of the laser receiver be denoted as , and the horizontal distance be denoted as : ; Combining the fixed coordinates of the laser emitter in the world coordinate system The world coordinates of the workpiece edge can be calculated as follows: ; Laser positioning requires measurements at four vertices of the workpiece edge, with the average value taken as the final edge coordinates.

[0021] Working principle: This invention provides an OLED display chip mounter, the specific steps of which are as follows: Step 1: The operator sets the placement parameters (such as OLED screen size, placement speed, positioning accuracy threshold, etc.) via the touch screen. Step 2: The substrate to be mounted is transported to the substrate positioning station by the screen substrate conveyor belt, and the OLED liquid crystal display screen is transported to the display screen positioning station by the screen conveyor. Step 3: The positioning mechanism is activated, and the industrial camera and laser positioning component collect their position information respectively, calculate the position deviation, and transmit it to the control system; Step 4: The control system controls the robotic arm of the mounting mechanism to move to the display screen positioning station, and the adsorption component picks up the OLED screen through the vacuum nozzle; Step 5: The six-axis robotic arm moves the OLED screen to the substrate positioning station. Based on the positioning deviation data, the position and angle of the OLED screen are adjusted by the angle adjustment component. The six-axis robotic arm slowly lowers the OLED screen and accurately attaches it to the substrate. Step 6: After the mounting is completed, the inspection mechanism is started. The high-precision vision inspection camera detects the mounting offset, the displacement sensor detects the bonding gap, and the detection data is transmitted to the control system. If the inspection is qualified, the finished product is sent away by the subsequent conveying mechanism; if it is unqualified, the alarm module sounds an alarm, and the operator handles the situation.

[0022] The following points should be noted in this article: 1. The accompanying drawings of the embodiments disclosed herein only relate to the structures involved in the embodiments disclosed herein; other structures can be referred to in general design.

[0023] 2. Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0024] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. An OLED display chip mounter, comprising a main body (1), a feeding mechanism, a positioning mechanism, a mounting mechanism, a testing mechanism, and a control system, characterized in that; The main body (1) is equipped with a positioning mechanism, a mounting mechanism and a control system. The positioning mechanism includes a first visual positioning component (102), a laser positioning component (103) and a second visual positioning component (403). The mounting mechanism includes a six-axis robotic arm (401). The six-axis robotic arm (401) is mounted on the worktable of the main body (1). Four vacuum nozzles (402) are mounted on the six-axis robotic arm (401). The visual positioning instrument of the second visual positioning component (403) is installed in the middle of the four vacuum nozzles (402) of the six-axis robotic arm (401). The six-axis robotic arm (401) and the four vacuum nozzles (402) constitute the mounting mechanism. The feeding mechanism includes a screen substrate conveyor (2) and a screen conveyor (3). The main body of the detection mechanism is a detection module (5). The detection module (5) includes a visual inspection camera (501), a displacement sensor and an alarm (502). The main body of the control system is a CNC host (101). The CNC host (101) controls the screen substrate conveyor (2), the screen conveyor (3), the mounting module (4) and the detection module (5).

2. The OLED display screen mounting machine according to claim 1, characterized in that: The feeding mechanism is used to transport the OLED liquid crystal display screen and the substrate to be mounted. The screen conveyor (3) is located on one side of the six-axis robotic arm (401). The screen substrate conveyor (2) is placed in the middle of the worktable of the main body (1), directly below the first visual positioning component (102) and the laser positioning component (103).

3. The OLED display chip mounter according to claim 1, characterized in that: The positioning mechanism is used to calibrate the position of the OLED liquid crystal display screen and the substrate to be mounted. The industrial camera of the second vision positioning component (403) is used to photograph the OLED screen on the screen conveyor (3). The image processing module of the CNC host (101) is used to analyze and process the image information, and after obtaining the position deviation data, it controls the four vacuum nozzles (402) of the six-axis robotic arm (401) to be fixed at the four corners of the OLED screen to adsorb and fix the OLED screen.

4. An OLED display chip mounter according to claim 1, characterized in that: When the display substrate on the screen substrate conveyor (2) is conveyed to the area directly below the first visual positioning component (102), the industrial camera of the first visual positioning component (102) is used to position the display substrate. The laser emitter of the laser positioning component (103) emits a laser beam, and the laser receiver receives the laser signal reflected by the edge of the workpiece to accurately position the edge coordinates of the workpiece. The CNC host (101) controls the six-axis robotic arm (401) to attach and install the OLED display.

5. An OLED display chip mounter according to claim 1, characterized in that: The visual inspection camera (501) of the detection module (5) is used to take pictures of the finished product image after the OLED display is attached to detect the attachment offset. The displacement sensor is used to detect the bonding gap between the OLED liquid crystal display and the substrate to be attached. The alarm (502) is used to issue an alarm signal when the equipment fails or the attachment is unqualified.

6. An OLED display screen mounting machine according to claim 1, characterized in that: During the positioning process, the first visual positioning component (102) and the second visual positioning component (403) first perform algorithm preprocessing on the image, first converting the image to grayscale, and then using Gaussian filtering to eliminate high-frequency noise in the acquired image: ； in, This represents the offset of a pixel within the filter template relative to the center. Given a Gaussian standard deviation, the pixel values ​​of the filtered image are: ； Where K is a template size setting constant; After removing high-frequency noise, the image is subjected to reference feature extraction using the cross-reference standard method to locate core marker points. A corner detection template matching combination algorithm is then used to identify the marker feature points. The feature point response function is as follows: ； in, , For local windows, For pixel gradient, For empirical coefficients, when A value greater than the maximum response value is identified as a corner point and denoted as . These are the pixel coordinates of the image; After determining the core location, template matching verification is performed. A standard template with a pre-stored crosshair reference point and pixel dimensions is used. The normalized cross-correlation coefficient between the detected corner regions and the template is calculated to exclude spurious feature points. The formula is as follows: ； in, As a standard template, To detect the region image, The average grayscale value of the template area. The grayscale mean of the detection area, when When a point is identified as a valid reference marker, the geometric centers of its four corner points are taken as the image coordinates of the reference marker. Finally, the image coordinates are converted to real-world coordinates, and camera distortion is calibrated. The radial distortion correction formula is: ; ； in, Let these be the coordinates of the camera's principal point. The radial distortion coefficient is a constant; The distance from the pixel to the principal point; By transforming the matrix Corrected image coordinates Convert to real coordinates The coordinate transformation formula is: ； Where the Z-direction is fixed, the average thickness of the workpiece is taken. For camera focal length, The world coordinates of the preset reference marker are the distance from the workpiece to the camera. The actual detection coordinates are ,but: Translational deviation in the X direction: Translational deviation in the Y direction: : Rotational deviation: ; in, The rotation angle for the preset reference mark.

7. An OLED display chip mounter according to claim 1, characterized in that: During the laser positioning process, the laser positioning component accurately detects the edges of the OLED display screen and its substrate to determine the position of the edges in the laser scanning direction. It then collects the laser beam emitted by the laser emitter and scans perpendicular to the workpiece edge. After reflection from the workpiece edge, the laser beam forms a continuous spot on the receiver, converting the light signal into a grayscale signal. The scan time corresponds to the CCD pixel column number, and then the grayscale signal is smoothed using a moving average filter. The calculation formula is as follows: ； in For window size, the difference formula is: ; Edge pixel position: ; Among them, it must meet the following requirements. , It is twice the mean of the differential signal, thus eliminating noise interference; Determine the fixed geometric parameters of the laser emitter and receiver: The horizontal distance between the transmitter and the receiver is The laser emission angle is ; pixel spacing is The receiver reference pixel position is ; The horizontal distance from the edge of the workpiece to the transmitter The calculation is as follows: ； in Let the equivalent focal length of the laser receiver be denoted as , and the horizontal distance be denoted as : ； Combining the fixed coordinates of the laser emitter in the world coordinate system The world coordinates of the workpiece edge can be calculated as follows: ； Laser positioning requires measurements at four vertices of the workpiece edge, with the average value taken as the final edge coordinates.

8. An OLED display screen mounting machine according to claim 1, characterized in that: Cleaning vacuum cleaners (104) are provided on both sides of the screen substrate conveying platform (2) on the main body (1). The cleaning vacuum cleaners (104) are used to remove static electricity and dust from the surface of the OLED liquid crystal display screen and the substrate to be mounted.

Images