A Mini-LED adhesive surface defect detection device and method based on photometric stereo method

Abstract

The present invention discloses a Mini-LED adhesive surface defect detection device and method based on photometric stereo method, including a detection platform, a mounting frame fixedly arranged on the top of the detection platform, a servo motor fixedly arranged on the top of the mounting frame, a fixing seat fixedly arranged on the lower side wall of the mounting frame, a rotating screw rod installed inside the fixing seat through a bearing, and a rotating connection assembly is arranged between the top of the rotating screw rod and the output shaft of the servo motor. The servo motor drives the rotating shaft to rotate by driving the connecting assembly, so that the driving gear drives the circular gear plate to rotate, so that the sliding sleeve drives the illumination lamp to make a circular motion, so that the illumination lamp illuminates the Mini-LED adhesive surface from different angles, avoids the situation that multiple light sources are used to illuminate the Mini-LED adhesive surface from different angles, avoids the situation that multiple light sources consume too much power resources, and avoids the simultaneous damage of multiple light sources to increase maintenance costs.

Description

Technical Field

[0001] The present invention relates to the technical field of Mini-LED adhesive surface defect detection, and in particular to a Mini-LED adhesive surface defect detection device and method based on photometric stereo method. Background Art

[0002] The Mini-LED chip is firmly fixed on the substrate. In order to prevent the chip from being displaced or loosened during use and to ensure its normal light emission and electrical connection, the Mini-LED chip will be fixed and packaged by colloid. The Mini-LED glue surface refers to the colloid surface used to fix and package the Mini-LED chip. In order to ensure the quality of the colloid surface, the colloid surface is usually tested to mainly check whether the glue surface is flat and smooth, and whether there are defects such as bubbles, cracks, glue deficiency, and glue overflow. The above-mentioned defects will affect the light emission effect and appearance quality of Mini-LED.

[0003] When detecting defects on the Mini-LED glue surface, a Mini-LED glue surface defect detection device based on the photometric stereo method is usually used. The Mini-LED is placed inside the detection device, and the Mini-LED glue surface is illuminated by the light source inside the device. The Mini-LED glue surface under the illumination of the light source is photographed by a camera, and the photographed graphic information is processed using the photometric stereo method to detect whether there are defects on the Mini-LED glue surface.

[0004] When the detection device detects the Mini-LED glue surface, it needs to illuminate the Mini-LED glue surface at different angles. Therefore, more than three light sources will be used, such as four, six or even more. Multiple light sources can illuminate from multiple angles, which can more delicately portray the three-dimensional features of the glue surface and more accurately detect various defects. However, using multiple light sources to illuminate the Mini-LED glue surface consumes more power resources, and during the use of multiple light sources, more than two light sources may be damaged, which increases the cost of light source maintenance of the detection device. Based on the above problems, the present application proposes a Mini-LED glue surface defect detection device and method based on photometric stereo. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a Mini-LED adhesive surface defect detection device and method based on photometric stereo method, which is used to solve the problems raised in the above background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A Mini-LED glue surface defect detection device and method based on photometric stereo method, including a detection platform, a mounting frame is fixedly arranged on the top of the detection platform, a servo motor is fixedly arranged on the top of the mounting frame, a fixing seat is fixedly arranged on the lower side wall of the mounting frame, a rotating screw is installed inside the fixing seat through a bearing, a rotating connection component is arranged between the top of the rotating screw and the output shaft of the servo motor, which is used to connect the output end of the servo motor with the rotating screw, a screw sleeve is threadedly arranged on the surface of the rotating screw, a fixing frame is fixedly arranged on the front side of the screw sleeve, a sealing cover is fixedly arranged on the bottom of the fixing frame, a blocking frame and a blocking plate are fixedly arranged inside the sealing cover, a shooting camera is fixedly arranged inside the blocking plate, a rotating component is arranged at the bottom of the blocking plate, an illumination lamp is arranged at the bottom of the blocking plate through the rotating component, a rotating shaft is rotatably arranged inside the sealing cover, a driving connection component is connected between the surface of the rotating shaft and the output end of the servo motor, which is used to drive the rotating shaft to connect the output end of the servo motor.

[0008] Preferably, the rotating connection assembly includes an upper ratchet sleeve fixedly mounted on the output end of the servo motor, a lower ratchet sleeve overlappingly arranged inside the upper ratchet sleeve, the lower ratchet sleeve slidably arranged on the surface of the rotating screw, a spring fixedly arranged at the bottom of the rotating screw, a connecting circular plate fixedly arranged at the bottom end of the spring, the connecting circular plate fixedly mounted on the surface of the rotating screw, a limiting groove is provided inside the lower ratchet sleeve, a limiting protrusion is slidably arranged inside the limiting groove, and the limiting protrusion is fixedly mounted on the surface of the rotating screw.

[0009] Preferably, the rotating assembly includes a circular slide rail fixedly mounted on the bottom of the blocking plate, a sleeve is slidably arranged on the surface of the circular slide rail, the lighting lamp is fixedly mounted on the bottom of the sleeve, a circular tooth plate is fixedly arranged on the surface of the sleeve, a driving gear is meshingly arranged on the surface of the circular tooth plate, and the driving gear is fixedly mounted on the bottom end of the rotating shaft.

[0010] Preferably, the driving connection assembly includes a rotating sleeve slidably arranged on the surface of the rotating shaft, a limit strip is slidably arranged inside the rotating sleeve, the limit strip is fixedly mounted on the surface of the rotating shaft, a synchronous wheel 1 is fixedly arranged on the outer surface of the rotating sleeve, a synchronous belt is meshed inside the synchronous wheel 1, a synchronous wheel 2 is meshed inside the synchronous belt, a groove is provided inside the synchronous wheel 2, a connecting sleeve is rotatably arranged inside the synchronous wheel 2, the connecting sleeve is fixedly mounted on the output end of the servo motor, a mounting groove is provided on the outer surface of the connecting sleeve, a fixed shaft is fixedly arranged inside the mounting groove, an arc plate is rotatably arranged on the surface of the fixed shaft, and a coil spring is connected between the surface of the arc plate and the surface of the fixed shaft.

[0011] Preferably, the blocking frame and the blocking plate are both made of light-absorbing material, the bottom of the blocking frame and the inside of the blocking plate are both black, a circular opening is provided through the top of the blocking plate, and a fixing block for installing a shooting camera is fixed inside the circular opening.

[0012] Preferably, the circular slide rail is composed of two semicircular slide rails, the number of the sliding sleeves is two, the two sliding sleeves are both slidably arranged on the surface of the circular slide rail, and the two sliding sleeves are both connected to the circular toothed plate.

[0013] Preferably, limiting circular plates for limiting the position of the second synchronous wheel are fixedly provided on both upper and lower sides of the connecting sleeve, and the limiting circular plates are in contact with the second synchronous wheel.

[0014] A Mini-LED adhesive surface defect detection method based on photometric stereo method comprises the following steps:

[0015] Step 1: Place the Mini-LED with encapsulated colloid on the top of the test bench, and use the output end of the servo motor to drive the rotating screw to rotate through the rotating connection assembly, so that the rotating screw drives the screw sleeve to move downward, and the screw sleeve drives the sealing cover to move downward through the fixing frame, so that the sealing cover contacts the top of the test bench;

[0016] Step 2: After the sealing cover contacts the top of the inspection table, the lighting lamp is powered on by the annular conductive slide rail, and the luminous lighting lamp is used as the light source for inspection. When the lighting lamp irradiates the Mini-LED adhesive surface, the Mini-LED is photographed by the camera, so that the camera captures the adhesive surface image under illumination. After the back end receives the collected multiple images, it is processed using the photometric stereo method. According to the Lambertian reflection model, combined with the known light source direction and the image pixel value captured by the camera, the grayscale change of each pixel under different illumination is calculated to solve the surface normal vector of each pixel point on the Mini-LED adhesive surface;

[0017] Step 3: When it is necessary to illuminate the Mini-LED rubber surface at different angles, the servo motor drives the output end to rotate in the opposite direction, so that the output end of the servo motor drives the rotating shaft to rotate inside the sealing cover through the driving connection component. At the same time, the rotating shaft drives the rotating component to drive the lighting lamp to make a circular motion, so that the lighting lamp moves to different angles to illuminate the Mini-LED rubber surface.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. In the Mini-LED adhesive surface defect detection device based on the photometric stereo method, the servo motor drives the rotating shaft to rotate by driving the connecting component, so that the driving gear drives the circular toothed plate to rotate, and the sliding sleeve drives the illumination lamp to make a circular motion, so that the illumination lamp illuminates the Mini-LED adhesive surface from different angles, avoiding the situation where multiple light sources are used to illuminate the Mini-LED adhesive surface from different angles, avoiding excessive power consumption by multiple light sources, and avoiding the increase of maintenance costs due to damage of multiple light sources at the same time.

[0020] 2. In the Mini-LED adhesive surface defect detection device based on the photometric stereo method, the servo motor drives the rotating screw to rotate through the rotating connection assembly, so that the screw sleeve drives the sealing cover to move downward through the fixed frame, and makes the sealing cover contact with the detection table, so as to protect the Mini-LED from light, avoiding the influence of external light sources on the Mini-LED adhesive surface detection, so that the image information captured during the Mini-LED adhesive surface detection is more accurate, thereby making the Mini-LED adhesive surface defect detection result more accurate.

[0021] 3. The Mini-LED adhesive surface defect detection device based on the photometric stereo method can block the light reflected from the Mini-LED adhesive surface to the sealing cover through the setting of a blocking frame and a blocking plate, and absorb the reflected light, thereby reducing the adverse effects of light leakage and ensuring the accuracy and high quality of lighting or display. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a positive isometric drawing of the structure of the present invention;

[0023] Figure 2 It is a schematic diagram of a longitudinal section of the structure of the present invention;

[0024] Figure 3 for Figure 2 A magnified view of the structure at B;

[0025] Figure 4 It is a schematic diagram of the local structure of the present invention;

[0026] Figure 5 for Figure 2 A magnified view of the structure at A;

[0027] Figure 6 This is a schematic diagram of the structure of the rotary connection assembly of the present invention;

[0028] Figure 7 This is a schematic diagram of the structure of the drive connection assembly of the present invention;

[0029] Figure 8 Based Figure 7 Enlarged view of the structure at location C.

[0030] In the figure: 1. test table; 2. mounting frame; 3. servo motor; 4. fixing seat; 5. rotating screw; 6. screw sleeve; 7. fixing frame; 8. sealing cover; 9. blocking frame; 10. blocking plate; 11. shooting camera; 12. circular slide rail; 13. sliding sleeve; 14. lighting lamp; 15. circular tooth plate; 16. driving gear; 17. rotating shaft; 18. upper ratchet sleeve; 19. lower ratchet sleeve; 20. spring; 21. connecting circular plate; 22. limiting groove; 23. limiting protrusion; 24. rotating sleeve; 25. limiting strip; 26. synchronous wheel one; 27. synchronous belt; 28. synchronous wheel two; 29. ​​groove; 30. connecting sleeve; 31. mounting groove; 32. fixed shaft; 33. arc plate; 34. coil spring. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Reference Figure 1-4A Mini-LED adhesive surface defect detection device and method based on photometric stereo method, including a detection platform 1, a mounting frame 2 is fixedly arranged on the top of the detection platform 1, a servo motor 3 is fixedly arranged on the top of the mounting frame 2, a fixing seat 4 is fixedly arranged on the lower side wall of the mounting frame 2, a rotating screw 5 is installed inside the fixing seat 4 through a bearing, a rotating connection component is arranged between the top of the rotating screw 5 and the output shaft of the servo motor 3, and is used to connect the output end of the servo motor 3 with the rotating screw 5, a threaded sleeve 6 is arranged on the surface of the rotating screw 5, a fixing frame 7 is fixedly arranged on the front side of the fixing frame 6, a sealing cover 8 is fixedly arranged on the bottom of the fixing frame 7, and a sealing cover 8 is fixedly arranged on the top of the sealing cover 8. A heat dissipation port is provided, through which the camera 11 can be cooled, thereby avoiding overheating of the camera 11 and avoiding thermal noise caused by temperature rise, which causes some random and messy pixels on the image, thereby avoiding the image quality used for detecting Mini-LED adhesive surface defects by the photometric stereo method from deteriorating, thereby affecting the subsequent accurate judgment and analysis of adhesive surface defects. A blocking frame 9 and a blocking plate 10 are fixedly provided inside the sealing cover 8. The blocking frame 9 and the blocking plate 10 are both made of light-absorbing materials. The bottom of the blocking frame 9 and the inside of the blocking plate 10 are both black. A circular opening is provided on the top of the blocking plate 10, and a fixed hole for The fixed block for mounting the shooting camera 11, the blocking frame 9 and the blocking plate 10 made of light-absorbing material can better absorb the light reflected from the Mini-LED adhesive surface to the sealing cover 8, and the black color can better absorb the light, thereby avoiding the influence of the light refracted by the sealing cover 8 on the detection of the Mini-LED adhesive surface. The shooting camera 11 is fixedly arranged inside the blocking plate 10, a rotating component is arranged at the bottom of the blocking plate 10, and an illumination lamp 14 is arranged at the bottom of the blocking plate 10 through the rotating component. A rotating shaft 17 is rotatably arranged inside the sealing cover 8, and a driving connection component is connected between the surface of the rotating shaft 17 and the output end of the servo motor 3 , used to connect the output end of the servo motor 3 to drive the rotating shaft 17, the servo motor 3 drives the rotating screw 5 and the rotating shaft 17 to rotate respectively through the rotating connection component and the driving connection component, wherein the rotating screw 5 rotates so that the screw sleeve 6 drives the sealing cover 8 to contact the detection table 1 through the fixing frame 7, so as to avoid the external light source from affecting the Mini-LED adhesive surface defect detection. When the rotating shaft 17 rotates, the rotating component drives the illumination lamp 14 to make a circular motion, so that the illumination lamp 14 irradiates the Mini-LED adhesive surface at different angles, and a single illumination lamp 14 can be used to complete the irradiation for Mini-LED adhesive surface defect detection.

[0033] As a preferred implementation in this embodiment, please refer to Figure 5 and Figure 6As shown, the rotary connection assembly includes an upper ratchet sleeve 18 fixedly mounted on the output end of the servo motor 3, a lower ratchet sleeve 19 is overlapped inside the upper ratchet sleeve 18, the lower ratchet sleeve 19 is slidably mounted on the surface of the rotating screw 5, a spring 20 is fixedly mounted at the bottom of the rotating screw 5, a connecting circular plate 21 is fixedly mounted at the bottom end of the spring 20, the connecting circular plate 21 is fixedly mounted on the surface of the rotating screw 5, a limiting groove 22 is provided inside the lower ratchet sleeve 19, a limiting protrusion 23 is slidably arranged inside the limiting groove 22, and the limiting protrusion 23 is fixedly mounted on the surface of the rotating screw 5 The servo motor 3 drives the lower ratchet sleeve 19 to rotate through the upper ratchet sleeve 18, and the lower ratchet sleeve 19 drives the rotating screw 5 to rotate through the limit groove 22 and the limit protrusion 23, so that the screw sleeve 6 drives the sealing cover 8 to contact the detection platform 1 through the fixing frame 7, thereby blocking the external light source, so that the Mini-LED glue surface defect detection does not need to be carried out in a light-proof room, making the Mini-LED glue surface defect detection device more convenient to use, and the Mini-LED glue surface defect detection device can be placed in any place for use.

[0034] As a preferred implementation in this embodiment, please refer to Figure 3 , Figure 4 , Figure 7 and Figure 8As shown, the drive connection assembly includes a rotating sleeve 24 slidably arranged on the surface of the rotating shaft 17, a limit strip 25 is slidably arranged inside the rotating sleeve 24, and the limit strip 25 is fixedly installed on the surface of the rotating shaft 17. A synchronous wheel 1 26 is fixedly arranged on the outer surface of the rotating sleeve 24, and a synchronous belt 27 is meshed inside the synchronous wheel 1 26. A synchronous wheel 28 is meshed inside the synchronous belt 27. A groove 29 is provided inside the synchronous wheel 28. A connecting sleeve 30 is rotatably arranged inside the synchronous wheel 28. The upper and lower sides of the connecting sleeve 30 are fixedly provided with a connection for the synchronous wheel 28. The limiting circular plate is used for limiting, and the limiting circular plate contacts the synchronous wheel 28. The position of the synchronous wheel 28 can be limited by the limiting circular plate, which prevents the synchronous wheel 28 from exerting downward pressure on the arc plate 33 due to its own gravity, thereby preventing the arc plate 33 from breaking. The connecting sleeve 30 is fixedly installed on the output end of the servo motor 3. The outer surface of the connecting sleeve 30 is provided with a mounting groove 31. A fixed shaft 32 is fixedly arranged inside the mounting groove 31. The surface of the fixed shaft 32 is rotatably provided with an arc plate 33. The surface of the arc plate 33 is connected to the surface of the fixed shaft 32. The rotating assembly includes a circular slide rail 12 fixedly mounted on the bottom of the blocking plate 10, a sleeve 13 is slidably arranged on the surface of the circular slide rail 12, a lighting lamp 14 is fixedly mounted on the bottom of the sleeve 13, a circular tooth plate 15 is fixedly arranged on the surface of the sleeve 13, the circular slide rail 12 is composed of two semicircular slide rails, the number of the sleeves 13 is two, the two sleeves 13 are slidably arranged on the surface of the circular slide rail 12, and the two sleeves 13 are connected to the circular tooth plate 15, the surface of the circular tooth plate 15 is meshed with a driving gear 16, and the driving gear 16 is fixed. Installed at the bottom end of the rotating shaft 17, the servo motor 3 drives the connecting sleeve 30 to rotate the synchronous wheel 28 through the fixed shaft 32 and the arc plate 33, and the synchronous wheel 28 drives the synchronous wheel 1 26 to rotate through the synchronous belt 27, so that the rotating sleeve 24 drives the rotating shaft 17 to rotate through the limit bar 25, so that the driving gear 16 pushes the circular toothed plate 15 to drive the sliding sleeve 13 to move, and drives the lighting lamp 14 to make a circular motion through the sliding sleeve 13, thereby changing the position of the lighting lamp 14, so that the lighting lamp 14 can illuminate the Mini-LED rubber surface at different angles.

[0035] A Mini-LED adhesive surface defect detection method based on photometric stereo method comprises the following steps:

[0036] Step 1: Place the Mini-LED encapsulated with colloid on the top of the test bench 1, and drive the rotating screw 5 to rotate through the output end of the servo motor 3 through the rotating connection assembly, so that the rotating screw 5 drives the screw sleeve 6 to move downward, and the screw sleeve 6 drives the sealing cover 8 to move downward through the fixing frame 7, so that the sealing cover 8 contacts the top of the test bench 1;

[0037] Step 2: After the sealing cover 8 contacts the top of the detection table 1, the lighting lamp 14 is powered on by the annular conductive slide rail, and the luminous lighting lamp 14 is used as the light source for detection. When the lighting lamp 14 irradiates the Mini-LED adhesive surface, the Mini-LED is photographed by the shooting camera 11, so that the shooting camera 11 captures the adhesive surface image under illumination. After the back end receives the collected multiple images, the photometric stereo method is used for processing. According to the Lambertian reflection model, combined with the known light source direction and the image pixel value captured by the camera, the grayscale change of each pixel under different illumination is calculated to solve the surface normal vector of each pixel point on the Mini-LED adhesive surface;

[0038] Step 3: When it is necessary to illuminate the Mini-LED rubber surface at different angles, the output end is driven by the servo motor 3 to rotate in the opposite direction, so that the output end of the servo motor 3 drives the rotating shaft 17 to rotate inside the sealing cover 8 through the driving connection component. At the same time, the rotating shaft 17 drives the rotating component to drive the lighting lamp 14 to perform a circular motion, so that the lighting lamp 14 moves to different angles to illuminate the Mini-LED rubber surface.

[0039] During use: when it is necessary to inspect the Mini-LED adhesive surface, place the Mini-LED on the top of the inspection table 1, and the servo motor 3 drives the output end to drive the upper ratchet sleeve 18 to rotate, so that the vertical surface of the upper ratchet sleeve 18 pushes the vertical surface of the lower ratchet sleeve 19, so that the upper ratchet sleeve 18 drives the lower ratchet sleeve 19 to rotate, and the lower ratchet sleeve 19 drives the rotating screw 5 to rotate through the limit groove 22 and the limit protrusion 23, so that the screw sleeve 6 drives the fixing frame 7 to move downward, and the fixing frame 7 drives the sealing cover 8 to contact with the top of the inspection table 1, and the lighting lamp 14 is energized through the annular conductive slide rail, so that the lighting lamp 14 illuminates the Mini-LED adhesive surface. The camera 11 is used to synchronously shoot the Mini-LED adhesive surface, and the captured image information is transmitted to the back end, which processes the image information through the photometric stereo method. During this process, the output end of the servo motor 3 drives the connecting sleeve 30 to rotate, so that the fixed shaft 32 drives the coil spring 34 and the arc plate 33 to move, and the arc plate 33 moves along the inclined surface of the groove 29, so that the groove 29 pushes the arc plate 33 to rotate on the surface of the fixed shaft 32, so that the arc plate 33 shrinks to the inside of the installation groove 31, and the arc plate 33 compresses the coil spring 34, then the synchronous wheel 28 does not rotate, and then the output end of the servo motor 3 drives the connecting sleeve 3 0 rotates in the opposite direction, the connecting sleeve 30 drives the arc plate 33 to move in the opposite direction through the fixed shaft 32, so that the arc plate 33 pushes the synchronous wheel 28 to rotate, the synchronous wheel 28 drives the synchronous wheel 1 26 to rotate through the synchronous belt 27, and the synchronous wheel 1 26 drives the rotating shaft 17 to rotate through the limit strip 25. In this process, the output end of the servo motor 3 drives the upper ratchet sleeve 18 to rotate, so that the upper ratchet sleeve 18 moves along the inclined surface of the lower ratchet sleeve 19, so that the lower ratchet sleeve 19 moves downward, and is compressed by the spring 20 so that the lower ratchet sleeve 19 does not rotate, so that the rotating shaft 17 drives the driving gear 16 to rotate, and the driving gear 16 drives the circular toothed plate 11 meshed with it. 5 rotates, and drives the sliding sleeve 13 to slide on the surface of the circular slide rail 12 through the circular tooth plate 15, so that the sliding sleeve 13 drives the illumination lamp 14 to make a circular motion, so that the illumination lamp 14 moves to different positions, so that the illumination lamp 14 illuminates the Mini-LED adhesive surface at different angles, so that the shooting camera 11 shoots the grayscale change of the Mini-LED adhesive surface under different illumination, and calculates the grayscale change of each pixel point under different illumination through the back end, and solves the surface normal vector of each pixel point of the Mini-LED adhesive surface. Based on these surface normal vectors, the depth map of the Mini-LED adhesive surface is further reconstructed, so as to obtain the three-dimensional shape information of the adhesive surface.

[0040] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0041] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A Mini-LED adhesive surface defect detection device based on photometric stereo method, comprising a detection platform (1), characterized in that: The top of the detection platform (1) is fixedly provided with a mounting frame (2), the top of the mounting frame (2) is fixedly provided with a servo motor (3), the lower side wall of the mounting frame (2) is fixedly provided with a fixing seat (4), a rotating screw (5) is installed inside the fixing seat (4) via a bearing, a rotating connection component is provided between the top of the rotating screw (5) and the output shaft of the servo motor (3), and is used for connecting the output end of the servo motor (3) with the rotating screw (5), a threaded sleeve (6) is provided on the surface of the rotating screw (5), a fixing frame (7) is fixedly provided on the front side of the screw sleeve (6), and the fixing frame (7) 7) A sealing cover (8) is fixedly arranged at the bottom, a blocking frame (9) and a blocking plate (10) are fixedly arranged inside the sealing cover (8), a shooting camera (11) is fixedly arranged inside the blocking plate (10), a rotating assembly is arranged at the bottom of the blocking plate (10), an illuminating lamp (14) is arranged at the bottom of the blocking plate (10) through the rotating assembly, a rotating shaft (17) is rotatably arranged inside the sealing cover (8), a driving connection assembly is connected between the surface of the rotating shaft (17) and the output end of the servo motor (3), and is used to drive the output end of the servo motor (3) to connect the rotating shaft (17).

2. According to claim 1, a Mini-LED adhesive surface defect detection device based on photometric stereo method is characterized in that: The rotary connection assembly comprises an upper ratchet sleeve (18) fixedly mounted on the output end of the servo motor (3); a lower ratchet sleeve (19) is overlappedly arranged inside the upper ratchet sleeve (18); the lower ratchet sleeve (19) is slidably arranged on the surface of the rotating screw (5); a spring (20) is fixedly arranged at the bottom of the rotating screw (5); a connecting circular plate (21) is fixedly arranged at the bottom end of the spring (20); the connecting circular plate (21) is fixedly mounted on the surface of the rotating screw (5); a limiting groove (22) is provided inside the lower ratchet sleeve (19); a limiting protrusion (23) is slidably arranged inside the limiting groove (22); and the limiting protrusion (23) is fixedly mounted on the surface of the rotating screw (5).

3. The Mini-LED adhesive surface defect detection device based on photometric stereo method according to claim 1, characterized in that: The rotating assembly comprises a circular slide rail (12) fixedly mounted on the bottom of the blocking plate (10); a sliding sleeve (13) is slidably arranged on the surface of the circular slide rail (12); the illumination lamp (14) is fixedly mounted on the bottom of the sliding sleeve (13); a circular toothed plate (15) is fixedly mounted on the surface of the sliding sleeve (13); a driving gear (16) is meshedly arranged on the surface of the circular toothed plate (15); and the driving gear (16) is fixedly mounted on the bottom end of the rotating shaft (17).

4. The Mini-LED adhesive surface defect detection device based on photometric stereo method according to claim 1, characterized in that: The driving connection assembly comprises a rotating sleeve (24) slidably arranged on the surface of the rotating shaft (17), a limit strip (25) slidably arranged inside the rotating sleeve (24), the limit strip (25) being fixedly mounted on the surface of the rotating shaft (17), a synchronous wheel 1 (26) being fixedly arranged on the outer surface of the rotating sleeve (24), a synchronous belt (27) being meshed inside the synchronous wheel 1 (26), a synchronous wheel 2 (28) being meshed inside the synchronous belt (27), and the synchronous wheel 2 (28) being meshed inside the synchronous belt (27). A groove (29) is provided inside the synchronous wheel (28), a connecting sleeve (30) is rotatably provided inside the synchronous wheel (28), the connecting sleeve (30) is fixedly installed on the output end of the servo motor (3), a mounting groove (31) is provided on the outer surface of the connecting sleeve (30), a fixed shaft (32) is fixedly provided inside the mounting groove (31), an arc plate (33) is rotatably provided on the surface of the fixed shaft (32), and a coil spring (34) is connected between the surface of the arc plate (33) and the surface of the fixed shaft (32).

5. The Mini-LED adhesive surface defect detection device based on photometric stereo method according to claim 1, characterized in that: The blocking frame (9) and the blocking plate (10) are both made of light-absorbing material; the bottom of the blocking frame (9) and the inside of the blocking plate (10) are both black; a circular opening is provided through the top of the blocking plate (10); a fixing block for mounting a shooting camera (11) is fixedly provided inside the circular opening.

6. The Mini-LED adhesive surface defect detection device based on photometric stereo method according to claim 3, characterized in that: The circular slide rail (12) is composed of two semicircular slide rails. The number of the slide sleeves (13) is two. The two slide sleeves (13) are both slidably arranged on the surface of the circular slide rail (12), and the two slide sleeves (13) are both connected to the circular toothed plate (15).

7. The Mini-LED adhesive surface defect detection device based on photometric stereo method according to claim 4, characterized in that: The connection sleeve (30) is fixedly provided with limiting circular plates on both upper and lower sides for limiting the position of the second synchronous wheel (28), and the limiting circular plates are in contact with the second synchronous wheel (28).

8. A Mini-LED adhesive surface defect detection method based on photometric stereo method according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: Place the Mini-LED encapsulated with colloid on the top of the test bench (1), and drive the rotating screw (5) to rotate through the output end of the servo motor (3) through the rotating connection assembly, so that the rotating screw (5) drives the screw sleeve (6) to move downward, and the screw sleeve (6) drives the sealing cover (8) to move downward through the fixing frame (7), so that the sealing cover (8) contacts the top of the test bench (1); Step 2: When the sealing cover (8) contacts the top of the detection platform (1), the lighting lamp (14) is powered on by the annular conductive slide rail, and the luminous lighting lamp (14) is used as the light source for detection. When the lighting lamp (14) irradiates the Mini-LED adhesive surface, the Mini-LED is photographed by the shooting camera (11), so that the shooting camera (11) captures the adhesive surface image under the illumination. After the back end receives the collected multiple images, the photometric stereo method is used for processing. According to the Lambertian reflection model, combined with the known light source direction and the pixel value of the image captured by the camera, the surface normal vector of each pixel point on the Mini-LED adhesive surface is solved by calculating the grayscale change of each pixel point under different illumination; Step 3: When it is necessary to illuminate the Mini-LED rubber surface at different angles, the servo motor (3) is used to drive the output end to rotate in the opposite direction, so that the output end of the servo motor (3) drives the rotating shaft (17) to rotate inside the sealing cover (8) through the driving connection component. At the same time, the rotating shaft (17) drives the rotating component to drive the lighting lamp (14) to make a circular motion, so that the lighting lamp (14) moves to different angles to illuminate the Mini-LED rubber surface.

Images