Mini LED and Micro LED binding offset checking device

Abstract

The utility model provides a Mini LED and Micro LED binding offset checking device which comprises an upper checking light source and a lower checking light source, the upper checking light source and the lower checking light source both comprise a coaxial light source and an annular light source, the annular light source is arranged on the lower side of the coaxial light source, the coaxial light source comprises a first shell, a first light source and a semi-transparent and semi-reflecting mirror, and the first shell is arranged on the first shell. The first light source is arranged on the left side in the first shell, the semi-transparent and semi-reflecting mirror is arranged on the right side in the first shell, and an inclined included angle is formed between the semi-transparent and semi-reflecting mirror and the horizontal line; the annular light source comprises a second shell and a second light source, the second light source is arranged in the shell and composed of a plurality of annular lamps arranged in parallel, a penetrating hole is formed in the middle of the top of the second shell, and the coaxial light source and the annular light source are infrared light sources. According to the utility model, lighting imaging is carried out by combining infrared coaxial light and low-angle infrared annular light, and the binding precision of a lightproof MINI / MICRO LED is checked.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of binding detection equipment in display panel manufacturing, and particularly relates to a Mini LED and Micro LED binding offset inspection device. BACKGROUND

[0002] In the manufacturing process of a display panel, Bonding is a key link, and the external connection of the driving or control signal of the display panel needs to rely on the compression of the display panel and the flexible wiring substrate or the compression of the display panel and the driving chip to realize the connection. However, due to mechanical errors, material deformation and other factors, offset may occur during the Bonding process, affecting the display effect and performance of the final product.

[0003] The precision inspection equipment after bonding on the market mainly relies on a camera to shoot the Mark on the Panel and the Mark on the COF (Chip On Film), and calculates the distance between the two Marks and the distance between the ITO Bump. For OLED Panel and COF, the light camera is easy to take pictures after lighting. However, when MINI LED and MICRO LED are checked, the circuit for mounting chips exists on the back of the MINI LED and MICRO LED, which makes visual recognition complex and confusing. The traditional inspection equipment cannot identify the position Mark of the Panel and the COF, so it cannot perform accurate offset inspection. SUMMARY

[0004] To solve the above-mentioned defects, the utility model provides a Mini LED and Micro LED binding offset inspection device, which can automatically, efficiently and accurately complete the detection of the binding offset of Mini LED and Micro LED, thereby improving the production quality and efficiency of Mini LED and Micro LED.

[0005] In the first aspect, the utility model provides a Mini LED and Micro LED binding offset inspection device, which comprises:

[0006] A CCD camera is arranged on one side of the product to be inspected for product loading position compensation.

[0007] A CCD light source is arranged on one side of the product to be inspected to provide a light source for the CCD camera.

[0008] An upper inspection camera is arranged on the upper side of the product to be inspected for shooting and clear imaging of the upper side of the product to be inspected.

[0009] An upper inspection light source is arranged on the upper side of the product to be inspected to provide light source for the upper inspection camera; the upper inspection light source comprises a coaxial light source and a ring light source, the upper side of the coaxial light source is arranged as the upper inspection camera, the lower side of the coaxial light source is arranged as the ring light source, the coaxial light source comprises a first shell, a first light source and a semi-transparent half mirror, the first light source is arranged on the left side in the first shell, the semi-transparent half mirror is arranged on the right side in the first shell, and the semi-transparent half mirror is arranged at an inclined angle with the horizontal line; the ring light source comprises a second shell and a second light source, the second light source is arranged in the second shell, the second light source is composed of a plurality of ring lamps, and a through hole is arranged in the middle of the top of the second shell;

[0010] A lower inspection camera is arranged on the lower side of the product to be inspected to shoot the lower side of the product to be inspected and form clear images;

[0011] A lower inspection light source is arranged on the lower side of the product to be inspected to provide light source for the lower inspection camera.

[0012] In an embodiment of the utility model, the lower inspection light source comprises a coaxial light source and a ring light source, the lower side of the coaxial light source is arranged as the lower inspection camera, the upper side is configured with the ring light source, the coaxial light source comprises a first shell, a first light source and a semi-transparent half mirror, the first light source is arranged on the left side in the first shell, and the semi-transparent half mirror is arranged at an inclined angle on the right side in the first shell; the ring light source comprises a second shell and a second light source, the second light source is arranged in the second shell, the second light source is composed of a plurality of ring lamps, and a through hole is arranged in the middle of the bottom of the second shell.

[0013] In an embodiment of the utility model, the second shell is in the shape of a circular truncated cone, and the plurality of ring lamps are distributed at intervals from top to bottom.

[0014] In an embodiment of the utility model, the upper inspection light source and the lower inspection light source both adopt infrared light sources.

[0015] In an embodiment of the utility model, the upper inspection camera and the lower inspection camera are arranged on the Z-axis linear module through supports respectively, the Z-axis linear module is installed on a module mounting frame, the bottom of the module mounting frame is connected with the X-axis linear module through a sliding block, and one end of the X-axis linear module is connected with an X-axis servo motor.

[0016] In an embodiment of the utility model, the product to be inspected is installed on a platform, and the platform is arranged on the Y-axis linear module, one end of the Y-axis linear module is connected with a Y-axis servo motor.

[0017] In summary, the utility model provides a Mini LED and Micro LED binding offset inspection device, and the utility model has the advantages of:

[0018] The utility model adopts the way of infrared coaxial light and low angle infrared annular light combination to carry out lighting imaging, and successfully solves the problem of Mini LED and Micro LED binding precision inspection. This method replaces the current artificial inspection method or the method of resistance determination through ART (Automated Resistance Testing, namely automatic resistance testing).

[0019] The utility model discloses through the automatic detection process, reduces manual intervention, improves detection speed greatly, and finds Bonding deviation problem in time, and this helps to avoid unqualified product flow into the subsequent production link, guarantees product quality stability. Meanwhile, using infrared annular light source frontal photographing clear, can carry out photographing on multilayer material. Combined with high accuracy image recognition technology, ensure the accuracy of detection result. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The utility model provides the three -dimensional structure schematic diagram of Mini LED and Micro LED binding deviation inspection device for an embodiment of the utility model.

[0021] Figure 2 The utility model discloses a structure schematic drawing of infrared light source for an embodiment of the utility model.

[0022] Figure 3 It is general product structure schematic diagram.

[0023] Figure 4 It is offset system for opaque COF product offset calculation parameter schematic diagram.

[0024] Figure 5 It is FPC binding on the product of COF upper portion and lower portion

[0025] Figure 6 It is two side edge products.

[0026] Figure 7 It is the bending product.

[0027] Figure 8 It is the effect picture of lighting imaging for opaque COF product.

[0028] Figure 9 It is the effect picture of lighting imaging for opaque COF product.

[0029] Figure 10 It is offset system for opaque FPF product offset calculation parameter schematic diagram.

[0030] Main element symbol description: 1, base; 2, platform; 21, Y-axis linear module; 3, X-axis linear module; 4, Z-axis linear module; 41, module mounting frame; 5, support; 6, upper inspection camera; 61, lens; 7, upper infrared light source; 71, infrared coaxial light source; 711, first light source; 712, half-transmission half-reflection mirror; 72, infrared ring light source; 721, second light source; 722, through hole; 8, lower inspection camera; 9, lower infrared light source. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0032] As shown in Figure 1 A Mini LED and Micro LED binding offset inspection device includes a base 1, a CCD camera, a white light source, an upper inspection camera 6, an upper infrared light source 7, a lower inspection camera 8, and a lower infrared light source 9.

[0033] The CCD camera is arranged on one side of the product to be inspected, and is used to capture the MARK on the product to be inspected and calculate the position of the product to be inspected.

[0034] The CCD light source is arranged on one side of the product to be inspected and provides light source for the CCD camera.

[0035] The upper inspection camera 6 is arranged on the upper side of the product to be inspected, and is used to capture the upper side of the product to be inspected and perform clear imaging. The lower side of the upper inspection camera 6 is provided with a lens 61.

[0036] The upper inspection light source 7 is arranged on the upper side of the product to be inspected and provides light source for the upper inspection camera 6. As Figure 2As shown, the upper inspection light source 7 comprises a coaxial light source 71 and a ring light source 72, the upper side of the coaxial light source 71 is provided as the upper inspection camera 6, the lower side of the coaxial light source 71 is provided as the ring light source 72, the coaxial light source 71 comprises a first shell, a first light source 711 and a semi-transparent half mirror 712, the first light source 711 is arranged on the left side in the first shell, the semi-transparent half mirror 712 is arranged on the right side in the first shell, and the semi-transparent half mirror 712 forms an inclined angle with the horizontal line; the ring light source 72 comprises a second shell and a second light source 721, the second light source 721 is arranged inside the second shell, the second light source 721 is composed of a plurality of parallel arranged ring lamps, and a through hole 722 is arranged in the middle of the top of the second shell. Preferably, the inside of the second shell is in the shape of a circular truncated cone, and the plurality of ring lamps are distributed at intervals from top to bottom.

[0037] The lower inspection camera 8 is arranged on the lower side of the product to be inspected, and is used for shooting the lower side of the product to be inspected and clearly imaging.

[0038] The lower inspection light source 9 is arranged on the lower side of the product to be inspected, and provides a light source for the shooting of the lower inspection camera 8. The lower inspection light source 9 has the same structure and principle as the upper inspection light source 7. The lower inspection light source 9 comprises a coaxial light source and a ring light source, the lower side of the coaxial light source is provided as the lower inspection camera 8, the upper side of the coaxial light source is provided as the ring light source, the coaxial light source comprises a first shell, a first light source and a semi-transparent half mirror, the first light source is arranged on the left side in the first shell, the semi-transparent half mirror is arranged on the right side in the first shell, and the semi-transparent half mirror forms an inclined angle with the horizontal line; the ring light source comprises a second shell and a second light source, the second light source is arranged inside the second shell, the second light source is composed of a plurality of parallel arranged ring lamps, and a through hole is arranged in the middle of the bottom of the second shell. Preferably, the inside of the second shell is in the shape of an inverted circular truncated cone, and the plurality of ring lamps are distributed at intervals from top to bottom.

[0039] Further, the semi-transparent half mirrors in the upper inspection light source 7 and the lower inspection light source 9 can be further attached with band-pass / high-pass filtering effect according to needs, all of which belong to the protection scope of the utility model.

[0040] Further, the upper inspection light source and the lower inspection light source both adopt infrared light sources. Only the infrared light source (wavelength greater than 800nm), and the specific wavelength can be further optimized according to the product characteristics, such as 930, 960, 1100 and other wave bands, which have different penetration effects on electronic product substrates.

[0041] Further, the upper inspection camera 6 and the lower inspection camera 8 are respectively installed on the Z-axis linear module 4 through the bracket 5, the Z-axis linear module 4 is installed on the module mounting frame 41, the bottom of the module mounting frame 41 is connected with the X-axis linear module 3 through a sliding block, the X-axis linear module 3 is installed on the upper side of the base 1, and one end of the X-axis linear module 3 is connected with the X-axis servo motor.

[0042] Further, the upper inspection camera 6 and the lower inspection camera 8 are preferably area array cameras.

[0043] Further, the product to be inspected is installed on the platform 2, the platform 2 is arranged on the Y-axis linear module 21, and the Y-axis linear module 21 is installed on the upper side of the base 1. One end of the Y-axis linear module 21 is connected with the Y-axis servo motor.

[0044] As shown in Figure 3 , there are multiple side edges for a single product panel, and each side edge contains multiple groups of COG / FOC. The current detection product contains a COG (IC) side edge and a FOG (FPC) side edge at the top of the panel, and each side edge contains a group of COG / FOC. The offset inspection system is also compatible with different numbers of side edges and different numbers of COG / FOC on the panel.

[0045] The Mini LED and Micro LED binding offset inspection process includes the following steps:

[0046] S1, binding the fields of view of the upper inspection camera and the lower inspection camera, including the following process:

[0047] S11, placing a transparent calibration plate at the position of the product to be detected;

[0048] S12, the upper inspection camera and the lower inspection camera take pictures at the same time, and the transparent calibration plate is photographed;

[0049] S13, calibrating the intrinsic matrix of each of the two inspection cameras through the transparent calibration plate;

[0050] S14, using the transparent calibration plate, flipping and coinciding the pictures taken by the two inspection cameras after calibration by the intrinsic matrix, and calculating the projection relationship matrix.

[0051] By using the transparent calibration plate as a bridge, the fields of view of the upper inspection camera and the lower inspection camera can be closely related. When the two cameras capture the top and bottom images of the opaque object respectively, the relative position relationship of the upper and lower surfaces of the object can be accurately calculated according to the principle of field of view projection.

[0052] In addition, if the fields of view of the upper and lower cameras do not coincide, the use range of the transparent calibration plate can be expanded as a calibration medium to accurately calibrate and convert the relative position relationship between the fields of view of the two cameras, and ensure the accuracy of the measurement.

[0053] S2, the mechanical hand picks up the product, moves above the loading camera, first moves to the left Mark point, the PLC controller or host PC receives the signal through the motion control card and controls the shooting, completes the left Mark shooting, the mechanical hand moves to the right Mark point, the PLC controller or host PC receives the signal through the motion control card and controls the shooting, completes the right Mark shooting, and the vision feedback shooting completion result OK / NG;

[0054] S3, after the PLC controller or host PC receives the shooting result OK signal through the motion control card, triggers the vision system to calculate the alignment, and compensates the position and angle;

[0055] S4, the PLC controller or host PC drives the mechanical hand to place the product on the platform 2 according to the alignment calculation result, and the platform 2 moves along the Y direction to be directly below the inspection camera 6;

[0056] S5, the PLC controller or host PC sends a single side edge detection instruction;

[0057] S6, the detection system drives the Z axis to move to the COF shooting height, drives the X axis to move from right to left to complete the offset shooting of the COF and the panel, performs image preprocessing on the image, then binarizes and segments, and finally completes the offset calculation;

[0058] Further, a distance measuring device is added in step S6, and the distance measured by the distance measuring device triggers the adjustment of the Z axis.

[0059] Since the offset inspection requires high detection accuracy, the depth of field of the camera is very shallow at this time (for example, when the magnification is 5x, the lens depth of field is only 0.09mm), and a distance measuring device can be added to obtain better shooting effect:

[0060] The measurement of the distance measuring device (laser range finder / spectral confocal range finder, etc.) and the linkage of the Z axis can realize more accurate shooting position control and obtain better shooting effect, and the measurement action has two implementation ways:

[0061] (1) The off-axis triggering mechanism is adopted, and the distance measuring device and the photographic lens do not share the same axis. Through the accurate movement of the Y axis, the distance measurement is first completed, and then the necessary compensation adjustment is made along the Z axis according to the measurement result, finally ensuring shooting at the best position to realize accurate image capture.

[0062] (2) For the coaxial measurement technology, a triangular laser layout deviating from the main optical axis of the lens is adopted, or a specially designed lens is introduced, so as to realize the active distance measuring function through the lens itself. This technology can accurately control the distance between the product to be detected and the lens, and thus significantly improve the clarity of the shooting and the overall imaging quality.

[0063] In step S6, Figure 4 As shown, the detection system is provided with a COF inspection box, a Panel ITO inspection box and an ITOPattern box. The COF inspection box is used to detect the lider line and center line of the COF; the Panel ITO inspection box is used to detect the panel ITO line and center line; the ITO Pattern box is used to detect the panel ITO offset detection area; offset calculation X: the distance between the center of the COF lider line and the center line of the panel ITO line; offset calculation Y: the distance between the center of the ITO Pattern and the center of the COFMark in the Y direction; offset angle calculation T: the difference between the left and right offset Y values ​​LY-RY.

[0064] S7. Platform 2 moves the Y axis to the FPC photo position. The PLC controller or main control PC triggers the left mark photo again. Then the detection system drives the X axis to move to complete the right mark photo. Finally, the offset calculation of the binding area between the FPC and the panel is completed.

[0065] There are several possibilities for product bonding: (1) One-sided bonding, where bonding is performed on only one of the four sides; (2) Two-sided bonding, where bonding is performed on two opposite sides of the product (upper and lower or left and right); and (3) L-shaped bonding, where bonding is performed on two adjacent sides of the product.

[0066] The mobile stage needs to be compatible with the above bonding arrangements. The following steps need to be repeated for each bonding edge.

[0067] For example, when the product has a second bottom side bonding, step S8 is also included. Step S8 includes the following process: the platform returns to the loading camera position, the product is rotated 180°, and the loading and photographing inspection process is repeated. The robot picks up the product and places it directly above the CCD camera. The left mark and right mark are photographed respectively. The PLC controller or main control PC sends the left and right mark photographing instructions in turn. The detection system completes the photographing and performs the alignment calculation. The platform moves the Y axis to the FPC photographing position. The PLC controller or main control PC receives the side completion signal and triggers the left mark photographing again. Then the detection system drives the X axis to move to complete the right mark photographing. Finally, the offset calculation of the binding area between the FPC and the panel is completed.

[0068] Further examples:

[0069] like Figure 5 As shown, the process is COF+FOF, first bind COF to the glass cover, then bind FPC to the glass cover with COF. Figure 5The upper part of the figure shows the process of attaching the FPC to the upper part of the COF, and the lower part shows the process of attaching the FPC to the lower part of the COF. Depending on the process, you can choose to use the upper or lower area scan camera.

[0070] Inspection method: Use the offset inspection system to take pictures of the binding area between the COF and the panel through the upper array camera for offset inspection; then use the upper array camera or the lower array camera to check the binding offset of the FPC according to the lighting imaging.

[0071] like Figure 6 As shown, the process is as follows: COF+FOF: First, the COF is bonded to the glass cover at the top, and then the FPC is bonded to the glass cover with COF. FOG: The FPC is bonded to the glass cover at the bottom.

[0072] Inspection method: Use the upper array camera to take pictures of the binding area between the COF and the panel for offset inspection; use the upper array camera or the lower array camera to detect the binding offset of the FPC according to the lighting imaging; rotate the product 180° and use the upper array camera to take pictures of the binding area between the FPC and the panel for offset inspection.

[0073] like Figure 7 As shown in the figure, the process is as follows: FPC on COF + COF on Glass: First, the FPC is bonded to the COF at the top, and then the COF with FPC is bonded to the glass cover. FOG: The FPC is bonded to the glass cover at the bottom.

[0074] Inspection method: Use the upper array camera to take pictures of the binding area between COF and panel for offset inspection; rotate the product 180°, and use the upper array camera to take pictures of the binding area between FPC and panel for offset inspection.

[0075] For opaque COF products, white light cannot penetrate their surface to reveal the mark image behind them. However, by using infrared light for illumination and combining it with the image processing technology of the offset inspection system, the image quality is significantly improved. Figure 8 As shown in the figure, the optimized image features are as follows: the transition pixels are controlled at 4 pixels or less, and the contrast achieves obvious differences from 118 to 52 (i.e. 66 grayscale differences) and from 92 to 50 (i.e. 42 grayscale differences).

[0076] For opaque FOF products, white light cannot penetrate the surface to capture the mark image behind it. However, by introducing infrared light for illumination and applying the offset inspection system for subsequent imaging processing, the image quality is significantly improved. Figure 9As shown, the optimized image presents the following characteristics: transition pixel control is within 6 pixels or less; in terms of contrast, significant gray scale differences of 226 to 62 (i.e., 164 gray scale difference), 234 to 87 (i.e., 147 gray scale difference), 193 to 91 (i.e., 102 gray scale difference), and 188 to 63 (i.e., 125 gray scale difference) are achieved.

[0077] Generally, when the gray scale difference exceeds 20, the algorithm can more stably calculate the offset value of the image. In contrast, if the surface layer cannot be penetrated, the gray scale difference will be zero, and effective measurement cannot be performed.

[0078] For opaque FOF products, such as Figure 10 As shown, for the case where the COF is blocked: the FPC cross Mark blocks 1-3 COF reference frames, resulting in the inability to locate the COF cross reference line, so when 1-4 COF reference frames are located, a reference offset is added:

[0079] Offset calculation X = FPC cross reference line X - (COF Mark X + reference offset X);

[0080] Offset calculation Y = FPC cross reference line Y - (COF Mark Y + reference offset Y);

[0081] In Figure 10 :

[0082] FPC cross reference line: the center reference line obtained by detecting the FPC;

[0083] COF reference frame: the four reference frames on the COF;

[0084] COF cross reference line: the center cross line of the four reference frames on the COF;

[0085] Reference offset: the actual distance from the COF cross reference line to the COF reference frame;

[0086] Offset calculation method:

[0087] Offset calculation X: the distance between the FPC cross reference line and the COF cross reference line in the X direction;

[0088] Offset calculation Y: the distance between the FPC cross reference line and the COF cross reference line in the Y direction;

[0089] Offset calculation T (angle): the difference (LY-RY) between the left and right offsets Y.

[0090] The above merely describes preferred embodiments of the present application, and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A Mini LED and Micro LED bonding offset inspection device, characterized in that: It includes: A CCD camera, set on one side of the product to be inspected, used for product loading position compensation; A CCD light source, provided on one side of the product to be inspected, to provide light for the CCD camera to shoot; An upper inspection camera is provided on the upper side of the product to be inspected, and is used to photograph the upper side of the product to be inspected and obtain a clear image; An upper inspection light source is arranged on the upper side of the product to be inspected to provide light for the upper inspection camera to shoot; the upper inspection light source includes a coaxial light source and an annular light source, the upper side of the coaxial light source is set as the upper inspection camera, and the lower side of the coaxial light source is set as the annular light source, the coaxial light source includes a first shell, a first light source and a semi-transparent and semi-reflective mirror, the first light source is arranged on the left side of the first shell, the semi-transparent and semi-reflective mirror is arranged on the right side of the first shell, and the semi-transparent and semi-reflective mirror is at an inclined angle to the horizontal line; the annular light source includes a second shell and a second light source, the second light source is arranged inside the shell, the second light source is composed of a plurality of annular lights, and a through hole is provided in the middle of the top of the second shell; A lower inspection camera is installed on the lower side of the product to be inspected, and is used to take clear images of the lower side of the product to be inspected; The lower inspection light source is arranged on the lower side of the product to be inspected and provides light source for the lower inspection camera to shoot.

2. The Mini LED and Micro LED bonding offset inspection device according to claim 1, characterized in that: The lower inspection light source includes a coaxial light source and an annular light source. The lower side of the coaxial light source is set as a lower inspection camera, and the upper side is configured with an annular light source. The coaxial light source includes a first shell, a first light source and a semi-transparent and semi-reflective mirror. The first light source is set on the left side inside the first shell, and the semi-transparent and semi-reflective mirror is tilted and set on the right side inside the first shell; the annular light source includes a second shell and a second light source. The second light source is set inside the second shell. The second light source is composed of multiple annular lights, and a through hole is set in the middle of the bottom of the second shell.

3. The Mini LED and Micro LED bonding offset inspection device according to claim 1 or 2, characterized in that: The interior of the second shell is in a frustum shape, and a plurality of ring lights are distributed at intervals from top to bottom.

4. The Mini LED and Micro LED bonding offset inspection device according to claim 1 or 2, characterized in that: The upper inspection light source and the lower inspection light source are both infrared light sources.

5. The Mini LED and Micro LED bonding offset inspection device according to claim 1, characterized in that: The upper inspection camera and the lower inspection camera are respectively arranged on the Z-axis linear module through the bracket. The Z-axis linear module is installed on the module mounting frame. The bottom of the module mounting frame is connected to the X-axis linear module through a slider. One end of the X-axis linear module is connected to the X-axis servo motor.

6. The Mini LED and Micro LED bonding offset inspection device according to claim 1, characterized in that: The product to be inspected is installed on a platform, which is set on a Y-axis linear module. One end of the Y-axis linear module is connected to the Y-axis servo motor.

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