An electro-hydraulic repair process for display panels and an inkjet printing system

Abstract

This application relates to an electrohydraulic repair process and inkjet printing system for display panels, comprising: incoming material inspection of a defective substrate; determining the required printing parameters and functional liquid type for each defect location; calibrating the relative position of the defective substrate and the electrohydraulic printing repair assembly; sequentially placing the defective locations on the substrate directly below the print head; printing the corresponding functional liquid onto the defective locations with the print head perpendicular to the substrate; using a visual imaging device to perform real-time imaging preliminary inspection of the droplets of functional liquid falling onto the defective locations; using an imaging module to perform imaging re-inspection of the droplets at the defective locations; if the results of the preliminary inspection and re-inspection meet the repair requirements, repairing the next defective location is performed; otherwise, an alarm is triggered. This application ensures the normal operation of the repair process by performing real-time imaging preliminary and re-inspection of the functional liquid printed onto the defective locations, facilitating timely detection and troubleshooting of repair problems, and avoiding large-scale repair failures.

Description

Technical Field

[0001] This application relates to the field of display panel repair technology, and in particular to a fluid repair process and inkjet printing system for display panels. Background Technology

[0002] MicroLED (micro-light-emitting diode) display devices are widely used due to their advantages such as small size, low power consumption, high brightness, high color saturation, fast response, and long lifespan. To improve the yield of MicroLED display devices, the current manufacturing process involves precise addressing detection and repair of the LED chips after transfer, eliminating any non-displayable chips and thus improving the overall yield.

[0003] In related technologies, after finding chip defects using visual recognition technology, it is determined whether silver paste or insulating glue needs to be printed based on the defect type. If electrode repair is required, silver paste needs to be printed on the pads first. After placing the LED on the pads, insulating glue is then printed for encapsulation. If the encapsulation layer needs to be repaired, insulating glue is printed directly on the pads.

[0004] Generally, after printing the silver paste or insulating adhesive, the repaired substrate is then inspected using an AOI (Automated Optical Inspection) system to determine whether the repair result is acceptable.

[0005] However, after the entire defective substrate is repaired, the repaired substrate is inspected. It is easy to find that the accuracy of the printing point and the accuracy of the droplet volume are not up to standard. This can lead to the failure to repair the position of multiple defective points, making it difficult to adjust the printing device in time and adversely affecting the repair effect. Summary of the Invention

[0006] This application provides a fluid repair process and inkjet printing system for display panels to solve the technical problem in related technologies where, after the overall repair of a defective substrate is completed, the repaired substrate is inspected, and the accuracy of the printing point and the amount of droplets are often unqualified, resulting in unqualified repair of multiple defect points. This makes it difficult to adjust the printing device in time, which has an adverse effect on the repair effect.

[0007] In a first aspect, a current-current repair process for a display panel is provided, which includes the following steps:

[0008] Incoming material inspection is performed on defective substrates to obtain the location, size, and type of all defect points on the defective substrates.

[0009] Determine the required printing parameters and functional fluid type for each defect point based on the size and type of all defect points;

[0010] The relative positions of the defective substrate and the electrohydraulic printing repair assembly are calibrated so that the defective points on the defective substrate can be moved to directly below the printhead of the electrohydraulic printing repair assembly.

[0011] Arrange the defect points on the defective substrate sequentially directly below the printhead;

[0012] Based on the printing parameters and the type of functional liquid, the print head is perpendicular to the defective substrate to print the corresponding functional liquid at the defective point.

[0013] The visual imaging device is used to perform real-time imaging and preliminary detection of the droplets of functional liquid falling to the defect point.

[0014] The imaging module is used to image and re-inspect the droplets at the defect points. The arrangement direction of the imaging module and the print head is consistent with the width or length direction of the pads on the defective substrate.

[0015] If the results of the preliminary inspection and re-inspection meet the repair requirements, the next defect point will be repaired; otherwise, an alarm will be triggered.

[0016] In some embodiments, determining the required printing parameters for each defect location based on the size and type of all defect locations includes:

[0017] Determine the diameter of the droplet to be printed at the defect location based on the size of the defect location;

[0018] Establish a database that maps multiple printing parameters to droplet diameters;

[0019] Determine the printing parameters based on the required droplet diameter and the database.

[0020] In some embodiments, the printing parameters include bias voltage, amplitude voltage, ignition frequency, duty cycle, printing time, and printing height.

[0021] In some embodiments, establishing the database corresponding to the printing parameters and droplet diameter includes:

[0022] The droplet diameter was measured after a test print by changing the values ​​of each data in the printing parameters sequentially using the controlled variable method.

[0023] Multiple sets of printing parameters and corresponding droplet diameter data are obtained to form a database.

[0024] In some embodiments, the real-time imaging preliminary detection of the functional liquid droplet falling to the defect point using a visual imaging device includes:

[0025] Obtain the imaging direction of the visual imaging component and the imaging tilt angle θ of the plane where the defect point is located;

[0026] The visual imaging device is used to image the droplets of functional liquid falling to the defect point in real time to obtain the initial inspection image.

[0027] The actual length L and width X of the initial inspection image are determined based on the initial inspection image.

[0028] The actual first diameter of the droplet, D1, is determined based on the length L of the initial image.

[0029] According to D2=X / sinθ, the actual second diameter of the droplet is D2;

[0030] Determine whether the actual first droplet diameter D1 and the actual second droplet diameter D2 are both within the preset error range compared to the preset droplet diameter; if so, the initial inspection is qualified; otherwise, the initial inspection is unqualified.

[0031] In some embodiments, the preset error range includes no more than 15%.

[0032] In some embodiments, the electrofluid printing repair assembly includes multiple printheads, the multiple printheads and the imaging module are arranged along the same straight line, and the multiple printheads include at least one printhead for printing two types of functional liquids;

[0033] The step of positioning the defect points on the defective substrate sequentially directly below the printhead includes:

[0034] Based on the defect type of the defect points on the defective substrate, multiple defect points are sequentially positioned directly below the printhead of the corresponding functional liquid type.

[0035] In some embodiments, after performing incoming material inspection on the defective substrate to obtain the location, size, and type of all defect points on the defective substrate, the method further includes:

[0036] The center-to-center spacing of adjacent pads on the defective substrate along the arrangement direction of multiple printheads is measured and calibrated as a unit spacing.

[0037] Obtain the defect points of the same defect type on the defective substrate, and group the defect points of the same defect type in each row in the arrangement direction of multiple printheads. The number of defect points of the same defect type in each group shall not exceed the number of printheads corresponding to the same defect type.

[0038] The center spacing of multiple printheads is adaptively adjusted in real time to make the installation spacing an integer multiple of the unit spacing, and to make the center spacing of multiple printheads of the same defect type consistent with the center spacing of multiple defect points of the same defect type in the same group to be repaired.

[0039] In some embodiments, when the number of multiple printheads of the same defect type is greater than the number of defect points of the same defect type in the same group to be repaired, some printheads are shielded so that the number of working printheads corresponds to the number of defect points in the group.

[0040] The beneficial effects of the technical solution provided in this application include:

[0041] This application provides an electro-hydraulic repair process for a display panel. When repairing a defective substrate, the location, size, and type of all defect points on the substrate are determined through incoming material inspection. After subsequently calibrating the relative position of the defective substrate and the electro-hydraulic printing repair component, the component can be moved to the corresponding position on the substrate. The defect points are then repaired by printing functional fluid at the corresponding defect points using the electro-hydraulic printing repair component.

[0042] When repairing defective points, the printhead is perpendicular to the defective substrate and prints the corresponding functional liquid at the defective point. At this time, the electric field force between the printhead and the defective substrate is consistent with the direction of the functional liquid sprayed by the printhead. The functional liquid falls vertically to the defective point. The sprayed functional liquid is not easily disturbed by the horizontal force, which improves the landing accuracy of the functional liquid and thus improves the repair quality.

[0043] When the functional fluid falls to the defect point, the vision imaging device performs a preliminary detection of the droplet in real time, thus providing real-time information on the printing status of the functional fluid and allowing for a preliminary judgment on whether the repair is satisfactory. Therefore, simultaneous detection of the repair point during repair facilitates timely troubleshooting and adjustment of the current fluid repair printing assembly, preventing large-scale repair failures.

[0044] In addition, after the defect point is repaired, when the next defect point is moved under the print head, the repaired defect point passes under the imaging module during the movement. At this time, the imaging module performs imaging re-inspection on the repaired defect point to ensure that the point is repaired to a qualified standard. This facilitates timely detection and troubleshooting of repair problems, and allows for timely adjustment of the current fluid to repair the printing components, avoiding large-scale repair failures.

[0045] Secondly, an inkjet printing system is provided, comprising:

[0046] A motion platform is used to support the defective substrate and drive the defective substrate to move in a horizontal plane;

[0047] A vision system for imaging droplets printed in real time and droplets after printing;

[0048] An electrofluid printing repair assembly is used to print functional liquid onto the defect sites of the defective substrate.

[0049] The control system controls the motion platform, the vision system, and the electro-hydraulic printing repair component to operate according to the electro-hydraulic repair process of the display panel as described above.

[0050] Another embodiment of this application provides an inkjet printing system. Since the inkjet printing system operates according to the above-mentioned electro-hydraulic repair process of the display panel, the beneficial effects of the inkjet printing system are the same as the beneficial effects of the above-mentioned electro-hydraulic repair process of the display panel, and will not be repeated here. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 A flowchart of the electro-hydraulic repair process for the display panel provided in this application embodiment;

[0053] Figure 2 This is a schematic diagram of the defect locations on the defective substrate provided in an embodiment of this application;

[0054] Figure 3 This is a schematic diagram showing the process of printing droplets onto the repair points, as provided in an embodiment of this application.

[0055] Figure 4 A schematic diagram of the initial inspection graphic and the re-inspection image provided in the embodiments of this application;

[0056] Figure 5 A schematic diagram illustrating the process of processing defect points by the printhead and imaging module provided in the embodiments of this application;

[0057] Figure 6 This is a schematic diagram showing the adaptive adjustment of the center spacing of multiple printheads according to the positions of multiple defect points provided in the embodiments of this application. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0059] This application provides a current-current repair process and inkjet printing system for display panels. The current-current repair process performs real-time imaging inspection of the functional liquid printed to defective points, and during the switching of repaired defective points, performs imaging re-inspection of the already repaired defective points. This ensures the repair operation proceeds normally, facilitates timely detection and troubleshooting of repair problems, and allows for timely adjustment of the current-current repair printing components, avoiding large-scale repair failures. This application solves the technical problem in related technologies where, after the entire defective substrate is repaired, the inspected substrate is prone to issues with the accuracy of the printing device's placement and droplet volume, leading to unqualified repairs of multiple defective points. This makes it difficult to adjust the printing device in a timely manner, negatively impacting the repair effect.

[0060] Reference Figure 1 A current-current repair process for a display panel includes the following steps:

[0061] S100. Incoming material inspection is performed on the defective substrate to obtain the location, size and type of all defect points on the defective substrate.

[0062] S200: Determine the required printing parameters and functional fluid type for each defect location based on the size and type of all defect locations.

[0063] S300, calibrate the relative position of the defective substrate and the electrohydraulic printing repair assembly so that the defective point on the defective substrate can be moved to directly below the printhead of the electrohydraulic printing repair assembly.

[0064] S400: Position the defect points on the defective substrate sequentially directly below the printhead.

[0065] S500: Based on the printing parameters and the type of functional liquid, the print head is perpendicular to the defective substrate to print the corresponding functional liquid at the defective point.

[0066] S600: Real-time imaging and preliminary detection of functional liquid droplets falling to defect locations using visual imaging devices.

[0067] S700: The imaging module is used to image and re-inspect the droplets at the defect points. The arrangement direction of the imaging module and the print head is consistent with the width or length direction of the pads on the defective substrate.

[0068] S800: If the results of the preliminary inspection and re-inspection meet the repair requirements, proceed to repair the next defect location; otherwise, issue an alarm.

[0069] With this setup, when repairing a defective substrate, the location, size, and type of all defect points on the substrate are determined through incoming material inspection. After subsequently calibrating the relative position of the defective substrate and the electrofluid printing repair component, the component can be moved to the corresponding position on the substrate. The component then prints functional fluid at the corresponding defect points to repair them.

[0070] When repairing defective points, the printhead is perpendicular to the defective substrate and prints the corresponding functional liquid at the defective point. At this time, the electric field force between the printhead and the defective substrate is consistent with the direction of the functional liquid sprayed by the printhead. The functional liquid falls vertically to the defective point. The sprayed functional liquid is not easily disturbed by the horizontal force, which improves the landing accuracy of the functional liquid and thus improves the repair quality.

[0071] When the functional fluid falls to the defect point, the vision imaging device performs a preliminary detection of the droplet in real time, thus providing real-time information on the printing status of the functional fluid and allowing for a preliminary judgment on whether the repair is satisfactory. Therefore, simultaneous detection of the repair point during repair facilitates timely troubleshooting and adjustment of the current fluid repair printing assembly, preventing large-scale repair failures.

[0072] In addition, after the defect point is repaired, when the next defect point is moved under the print head, the repaired defect point passes under the imaging module during the movement. At this time, the imaging module performs imaging re-inspection on the repaired defect point to ensure that the point is repaired to a qualified standard. This facilitates timely detection and troubleshooting of repair problems, and allows for timely adjustment of the current fluid to repair the printing components, avoiding large-scale repair failures.

[0073] In this embodiment, if the initial inspection fails, an alarm is triggered directly. If the initial inspection passes, the process switches to repairing the next defect point. During the switching process, the repaired defect points are re-inspected. If the re-inspection fails, an alarm is triggered; if the re-inspection passes, the repair of the next defect point can continue.

[0074] It is important to note that the defect location refers to the position of the defective pad on the defective substrate. Each pad on the defective substrate has multiple sub-pads, and the distribution of these sub-pads is consistent across all pads. In this embodiment, the defect location is used to describe the defective pad on the defective substrate. During actual repair, each defect location, i.e., each pad, will have a corresponding repair sub-pad. Figure 2 In the diagram, for ease of explanation and understanding, each defect point is represented by a whole pad.

[0075] In step S100, the defective substrate undergoes incoming material inspection to obtain the location, size, and type of all defect points on the substrate. Specifically,

[0076] An AOI (Automated Optical Inspection) system is used to inspect the defective substrate to determine the location of defect points, the size of the pads at each defect point, and the type of defect at each defect point. In this embodiment, the defect types include electrode defects and packaging defects.

[0077] This setup allows for easy determination of the number of defective points on the defective substrate, as well as the location, size, and type of each defective point, after incoming material inspection, facilitating targeted repair of each defective point in the future.

[0078] In this embodiment, before substrate repair, defective substrates can be inspected in large quantities upon arrival, and the defect status of each defective substrate can be recorded using marking features. When repairing defective substrates, the defect status can be determined by scanning the marking features on the defective substrate, allowing for targeted repair of multiple defective points on the substrate. The marking features include QR codes or barcodes, etc.

[0079] This setup allows for centralized inspection of incoming materials, which can further improve the efficiency of panel repair.

[0080] In step S200, the required printing parameters and functional fluid type for each defect point are determined based on the size and type of all defect points. Specifically,

[0081] Based on the defect type of each defect location, the type of functional liquid to be printed at that defect location is determined. In this embodiment, when the defect type is an electrode defect, nano-silver paste needs to be printed at the defect location to form an electrode on the corresponding pad; when the defect type is an encapsulation defect, insulating adhesive needs to be printed at the defect location to encapsulate on the corresponding pad.

[0082] Based on the size of each defect point, the required droplet diameter to be printed onto the corresponding pad can be determined. By controlling the printing parameters, the functional liquid can be sprayed out in a quantitative manner to meet the required droplet diameter.

[0083] Step S200, which involves determining the required printing parameters for each defect point based on the size and type of all defect points, includes steps S210-S230.

[0084] S210. Determine the diameter of the droplet to be printed at the defect location based on the size of the defect location.

[0085] S220. Establish a database that corresponds to multiple printing parameters and droplet diameters.

[0086] S230. Determine the printing parameters based on the required droplet diameter and the database.

[0087] This setup allows for the creation of a database, where the required droplet diameter is matched to the corresponding printing parameters. This enables the rapid adjustment of different printing parameters for different defect locations, improving repair efficiency and ensuring that the amount of droplet printed to the defect location meets the requirements, thus enhancing repair quality.

[0088] Specifically, step S210 involves determining the diameter of the droplet to be printed onto the defect location based on its dimensions. This includes:

[0089] The dimensions of the defective pads are measured using imaging, including the length and width of the pads. After determining the width of the defective pads, the diameter of the droplets printed onto the pads must be controlled to be smaller than the pad width. In this embodiment, the droplet diameter is 80-95% of the width of the defective pad to ensure that the functional liquid printed onto the defective pad does not overflow.

[0090] Step S220 involves establishing a database that maps multiple printing parameters to droplet diameters. This includes steps S221 and S222.

[0091] S221. Using the controlled variable method, change the values ​​of each data in the printing parameters one by one, and measure the droplet diameter after a trial print.

[0092] S222. Obtain multiple sets of printing parameters and corresponding data of droplet diameter to form a database.

[0093] This setup establishes a database of multiple sets of printing parameters and their corresponding droplet diameters by sequentially changing the printing parameters and conducting trial prints. This makes it convenient to directly match the required printing parameters with the desired droplet diameter during actual repairs.

[0094] In step S221, the printing parameters include bias voltage, amplitude voltage, ignition frequency, duty cycle, printing time, and printing height. By controlling variables, one parameter is gradually changed each time to perform multiple trial prints, thereby obtaining multiple sets of corresponding droplet diameter data.

[0095] Specifically, the bias voltage varies from 0 to 500V, and each change in bias voltage includes 10-20V. When the bias voltage is fixed, the bias voltage is 180V.

[0096] The amplitude voltage variation range is 0-1000V, and each amplitude voltage change includes 10-20V. When the amplitude voltage is fixed, the amplitude voltage is 300V.

[0097] The ignition frequency varies from 1 to 1000 Hz, with each change including 5-10 Hz. When the ignition frequency is fixed, it is 50 Hz.

[0098] The printing time varies from 1 to 50 ms, with each variation including 1-5 ms. When printing a fixed quantity, the printing time is 30 ms.

[0099] The printing height varies from 10 to 40 micrometers, with each change ranging from 1 to 3 micrometers. When the printing height is fixed, the printing height is 20 micrometers.

[0100] The duty cycle varies from 0% to 100%, and each change in duty cycle includes 5% to 10%. When the duty cycle is fixed, it is 50%.

[0101] It should be noted that different types of functional liquids have different material properties, so the correspondence between printing parameters and droplet diameter is different, and a corresponding database needs to be established for each type of functional liquid.

[0102] This setting allows for the correlation between printing parameters and droplet diameter to be obtained by changing the parameters multiple times. This facilitates adaptive adjustment of printing parameters when repairing defect points, thereby improving repair quality.

[0103] In step S300, the relative positions of the defective substrate and the electrohydraulic printing repair assembly are calibrated so that the defect points on the defective substrate can be moved directly below the print head of the electrohydraulic printing repair assembly. Specifically,

[0104] By capturing the marked points on the defective substrate, the location of the defective substrate is determined. Since the location of the defective substrate is determined, the locations of all defective points on the substrate are also determined, thus establishing the relative positions of the defective substrate, all defective points, and the current-current printing repair assembly. This facilitates the subsequent sequential repair of all defective points by the current-current printing repair assembly.

[0105] In this embodiment, after determining the location of the defective substrate, the substrate is then corrected so that the length or width direction of the pads on the defective substrate is aligned with the scanning motion direction of the row-by-row repair process. Specifically, the length direction of the pads on the defective substrate is aligned with the scanning motion direction of the row-by-row repair process. It is understood that the current-current printing repair assembly repairs each row of defective points on the substrate sequentially. With the relative movement of the defective substrate with respect to the current-current printing repair assembly, it is ensured that multiple defective points can be moved directly below the printhead of the current-current printing repair assembly.

[0106] This configuration allows for line-by-line repair of defective points on the substrate during subsequent repairs, improving repair efficiency.

[0107] In step S400, the defect points on the defective substrate are sequentially positioned directly below the print head. Specifically, as the defective substrate moves relative to the electrohydraulic printing repair assembly, multiple defect points can be moved to directly below the print head of the electrohydraulic printing repair assembly for sequential repair.

[0108] In step S500, based on the printing parameters and the type of functional liquid, the print head is positioned perpendicular to the defective substrate to print the corresponding functional liquid at the defective points. Specifically,

[0109] The printhead operates using corresponding printing parameters, and the corresponding functional liquid is vertically printed to the defect location based on the type of functional liquid required. For electrode defects, the printhead prints nano-silver paste to the defect location; for encapsulation defects, the printhead prints insulating adhesive to the defect location.

[0110] With this setup, when repairing defective points, the printhead is perpendicular to the defective substrate and prints the corresponding functional liquid onto the defective point. At this time, the electric field force between the printhead and the defective substrate is consistent with the direction of the functional liquid sprayed by the printhead. The functional liquid falls vertically to the defective point, and the sprayed functional liquid is not easily disturbed by the horizontal force, which improves the landing accuracy of the functional liquid and thus improves the repair quality.

[0111] In step S600, a visual imaging device is used to perform real-time imaging and preliminary detection of the droplets that fall to the defect point.

[0112] Because the printhead is positioned perpendicular to the plane where the defect is located, the plane of the vision imaging element, perpendicular to the defect, images the droplet printed onto the defect in real time due to interference from the installation position. Therefore, the imaging direction of the vision imaging element has an angle with the plane where the defect is located.

[0113] Reference Figure 3 Step S600 specifically includes steps S610-S660.

[0114] S610. Obtain the imaging direction of the visual imaging component and the imaging tilt angle θ of the plane where the defect point is located.

[0115] S620: The visual imaging device is used to perform real-time imaging of the droplets of functional liquid falling to the defect point to obtain the initial inspection image.

[0116] S630. Based on the initial inspection image, the actual length L and width X of the initial inspection image are obtained.

[0117] S640. Based on the length L of the initial inspection image, the actual droplet first diameter D1 is determined.

[0118] S650. According to D2=X / sinθ, the actual droplet second diameter D2 is obtained.

[0119] S660. Determine whether the actual first droplet diameter D1 and the actual second droplet diameter D2 are both within the preset error range from the preset droplet diameter; if so, the initial inspection is qualified; otherwise, the initial inspection is unqualified.

[0120] This setup allows for analysis of the droplet imaging results by the visual imaging component, revealing whether the diameter of the droplet printed to the defect location meets the requirements. This enables real-time initial inspection of the repair process. Therefore, simultaneous detection of the repair point during repair facilitates timely troubleshooting and adjustment of the current fluid repair printing component, preventing large-scale repair failures.

[0121] Specifically, a true image of the droplet's actual state can be obtained by perpendicularly projecting an image onto the plane containing the defect. Generally, the true image of the droplet's actual state is circular. Since the visual imaging device images the droplet at an angle, a reference... Figure 4 Therefore, the real-time imaging result of the droplet by the visual imaging device is elliptical, that is, the initial detection image is elliptical.

[0122] By measuring the actual length L and width X of the initial inspection image, where the actual length L of the initial inspection image is the actual droplet first diameter D1 of the actual image of the droplet.

[0123] By using the imaging direction of the visual imaging device, the imaging tilt angle θ between the plane where the defect point is located, and the width of the initial inspection image, the actual second diameter D2 of the droplet in the actual image can be determined using D2 = X / sinθ. In this embodiment, the imaging tilt angle θ includes 10-45 degrees.

[0124] In addition, the preset droplet diameter D is the expected droplet diameter to be printed onto the defect location to meet the repair requirements, obtained through printing parameters, and is also the droplet diameter required at that defect location.

[0125] Therefore, by comparing the actual droplet diameters D1 and D2 with the preset droplet diameter D, it can be determined whether the printed droplet is qualified. If both the actual droplet diameters D1 and D2 are within the preset error range, the initial inspection is qualified; otherwise, the initial inspection is unqualified.

[0126] The visual imaging component includes a camera.

[0127] In this embodiment, the preset error range is no greater than 15%.

[0128] This setup improves the accuracy of the initial inspection by detecting the dimensions in both directions of the initial inspection image to determine whether the repair of the defect points is up to standard.

[0129] Furthermore, by checking whether the position of the initial inspection image is on the pad corresponding to the defect point, the quality of the droplet landing point of the repair print can also be checked.

[0130] In step S700, the imaging module is used to image and re-inspect the droplets at the defect location. The arrangement direction of the imaging module and the print head is consistent with the width or length direction of the pads on the defective substrate. Specifically,

[0131] Reference Figure 5 After the defect point is repaired, when the next defect point is moved under the print head, the repaired defect point passes under the imaging module during the movement. At this time, the imaging module performs imaging re-inspection on the repaired defect point to ensure that the point is repaired qualified. This facilitates timely detection and troubleshooting of repair problems, and allows for timely adjustment of the current fluid to repair the printing components, avoiding large-scale repair failures.

[0132] Reference Figure 4 Specifically, the imaging module, perpendicular to the plane where the defect point is located, performs imaging detection on the droplet printed to the defect point to obtain a re-inspection image, thus obtaining the actual image of the droplet. Then, the actual droplet diameter D0 is obtained from the re-inspection image captured by the imaging module, and it is determined whether the error between the actual droplet diameter and the preset droplet diameter is within a preset error range. This preset error range is no greater than 15%.

[0133] In addition, the imaging module can more clearly determine the position of the droplets falling on the defect points, ensuring that the functional fluid is printed onto the pads corresponding to the defect points.

[0134] The imaging module includes a high-magnification camera.

[0135] This setup allows for real-time initial inspection of the repair effect using visual imaging components, followed by a final inspection using an imaging module after repair. The final inspection is interspersed throughout the switching of defect locations, minimizing impact on the processing cycle of the defective substrate repair. Therefore, it ensures that the defect location is repaired to a satisfactory standard, facilitates timely detection and troubleshooting of repair problems, and allows for prompt adjustments to the current-current fluid repair printing components, preventing large-scale repair failures.

[0136] In step S800, if the results of the preliminary inspection and re-inspection meet the repair requirements, the repair of the next defect point will proceed; otherwise, an alarm will be triggered.

[0137] Specifically, if both the initial inspection and the re-inspection are qualified, the repair of the next defect point can be carried out; if either the initial inspection or the re-inspection is unqualified, an alarm will be triggered and a shutdown message will be displayed so that the current fluid printing repair component can be repaired immediately.

[0138] Alarm prompts include, but are not limited to, voice alarms and light alarms.

[0139] In this embodiment, to improve repair efficiency, the electrofluid printing repair assembly includes multiple printheads arranged along a straight line with an imaging module. At least one of the printheads is used to print two types of functional liquids. Preferably, in this embodiment, one type of printhead is used to print nano-silver paste, and the other type is used to print insulating adhesive.

[0140] Step S400, which involves sequentially positioning the defect points on the defective substrate directly below the printhead, includes:

[0141] Based on the defect type of the defect points on the defective substrate, multiple defect points are sequentially positioned directly below the printhead of the corresponding functional liquid type.

[0142] Specifically, as the defect points are repaired sequentially, depending on the type of defect, the defect point is positioned below the corresponding printhead to print the corresponding functional liquid for repair. In this embodiment, there are two printheads, one for printing nano-silver paste and the other for printing insulating adhesive.

[0143] With this setup, during the repair process of the defective substrate, as the defective points move sequentially to the bottom of the electrofluid printing repair component, the printhead can repair the defective points without having to scan the defective substrate multiple times, thus improving repair efficiency.

[0144] Furthermore, after performing incoming material inspection on the defective substrate in step S100 to obtain the location, size, and defect type of all defect points on the defective substrate, the method further includes:

[0145] The center-to-center spacing of adjacent pads on the defective substrate along the arrangement direction of multiple printheads is measured and calibrated as a unit spacing.

[0146] Obtain the defect points of the same defect type on the defective substrate, and group the defect points of the same defect type in each row in the arrangement direction of multiple printheads. The number of defect points of the same defect type in each group shall not exceed the number of printheads corresponding to the same defect type.

[0147] The center spacing of multiple printheads is adaptively adjusted in real time to make the installation spacing an integer multiple of the unit spacing, and to make the center spacing of multiple printheads of the same defect type consistent with the center spacing of multiple defect points of the same defect type in the same group to be repaired.

[0148] This setup, by using multiple printheads and adaptively adjusting the spacing between them, allows multiple defect points to be located directly below multiple printheads simultaneously, enabling them to be repaired at the same time and improving repair efficiency.

[0149] In this embodiment, there are two types of printheads. Each type of printhead includes multiple printheads, preferably 2-4 printheads per type.

[0150] Reference Figure 6 After grouping the defect points of the same type in each row on the defective substrate, multiple defect points of the same type in each group are repaired simultaneously. Before repairing the next group of defect points, the center spacing of multiple printheads is adaptively adjusted to ensure that multiple printheads correspond to multiple defect points respectively.

[0151] It should be noted that as the defective substrate moves relative to the electrofluid printing repair component, different defect point groups of different defect types can be repaired alternately in the direction of movement of the defective substrate. As the defective substrate is scanned, all defect points on the defective substrate can be repaired, thereby improving the repair efficiency.

[0152] In this embodiment, when grouping defect points in each row, the number of defect points in each group is 1-4. The groups are based on the center-to-center spacing of the defect points. In this embodiment, among multiple defect points of the same type in each row, those with a center-to-center spacing of 2-20 units between adjacent defect points can be grouped together.

[0153] Furthermore, when the number of multiple printheads of the same defect type is greater than the number of defect points of the same defect type in the same group to be repaired, some printheads are shielded so that the number of working printheads corresponds to the number of defect points in the group.

[0154] This setting ensures that the number of working printheads matches the number of defect points that need to be repaired simultaneously, thus increasing the flexibility in the number of defect point groups.

[0155] This application provides an electro-hydraulic repair process for a display panel. When repairing a defective substrate, the location, size, and type of all defect points on the substrate are determined through incoming material inspection. After subsequently calibrating the relative position of the defective substrate and the electro-hydraulic printing repair component, the component can be moved to the corresponding position on the substrate. The defect points are then repaired by printing functional fluid at the corresponding defect points using the electro-hydraulic printing repair component.

[0156] When repairing defective points, the printhead is perpendicular to the defective substrate and prints the corresponding functional liquid at the defective point. At this time, the electric field force between the printhead and the defective substrate is consistent with the direction of the functional liquid sprayed by the printhead. The functional liquid falls vertically to the defective point. The sprayed functional liquid is not easily disturbed by the horizontal force, which improves the landing accuracy of the functional liquid and thus improves the repair quality.

[0157] When the functional fluid falls to the defect point, the vision imaging device performs a preliminary detection of the droplet in real time, thus providing real-time information on the printing status of the functional fluid and allowing for a preliminary judgment on whether the repair is satisfactory. Therefore, simultaneous detection of the repair point during repair facilitates timely troubleshooting and adjustment of the current fluid repair printing assembly, preventing large-scale repair failures.

[0158] In addition, after the defect point is repaired, when the next defect point is moved under the print head, the repaired defect point passes under the imaging module during the movement. At this time, the imaging module performs imaging re-inspection on the repaired defect point to ensure that the point is repaired to a qualified standard. This facilitates timely detection and troubleshooting of repair problems, and allows for timely adjustment of the current fluid to repair the printing components, avoiding large-scale repair failures.

[0159] Another embodiment of this application provides an inkjet printing system, including:

[0160] A motion platform is used to support the defective substrate and drive the defective substrate to move in a horizontal plane;

[0161] A vision system for imaging droplets printed in real time and droplets after printing;

[0162] An electrofluid printing repair assembly is used to print functional liquid onto the defect sites of the defective substrate.

[0163] The control system controls the motion platform, the vision system, and the electro-hydraulic printing repair component to operate according to the electro-hydraulic repair process of the display panel as described above.

[0164] Another embodiment of this application provides an inkjet printing system. Since the inkjet printing system operates according to the above-mentioned electro-hydraulic repair process of the display panel, the beneficial effects of the inkjet printing system are the same as the beneficial effects of the above-mentioned electro-hydraulic repair process of the display panel, and will not be repeated here.

[0165] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0166] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0167] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A process for electrowetting repair of a display panel, characterized in that, It comprises the following steps: Incoming inspection is performed on the defective substrate to obtain the position, size and defect type of all defect sites on the defective substrate; The printing parameters and functional liquid types required by each defect site are determined according to the size and defect type of all defect sites; The relative position of the defective substrate and the electro-fluid printing repair assembly is calibrated so that the defect sites on the defective substrate can be moved to the directly below the printing head of the electro-fluid printing repair assembly; The defect sites on the defective substrate are sequentially placed directly below the printing head; The printing head prints the corresponding functional liquid on the defect sites perpendicularly to the defective substrate according to the printing parameters and functional liquid types; The visual imaging element is used to perform real-time imaging preliminary inspection on the liquid drops of the functional liquid falling on the defect sites; After the repair of the defect sites is completed, the next defect site is moved to below the printing head, and in the moving process, the repaired defect sites pass below the imaging module, at which time the imaging module is used to perform imaging re-inspection on the liquid drops of the defect sites, and the arrangement direction of the imaging module and the printing head is consistent with the width direction or length direction of the pad arrangement on the defective substrate; If the results of the preliminary inspection and the re-inspection meet the repair requirements, the next defect site is repaired, otherwise, an alarm is given.

2. The current fluid repair process of display panel according to claim 1, wherein, The printing parameters required by each defect site are determined according to the size and defect type of all defect sites, which comprises: The drop diameter printed on the defect site is determined according to the size of the defect site; A database of the corresponding relationship between multiple printing parameters and drop diameters is established; The printing parameters are determined according to the required drop diameter and the database.

3. The current fluid repair process of display panel according to claim 2, wherein, The printing parameters comprise bias voltage, amplitude voltage, ignition frequency, duty cycle, printing time and printing height. 4.The current fluid repair process of display panel according to claim 2, wherein, The database of the corresponding relationship between multiple printing parameters and drop diameters comprises: The values of each data in the printing parameters are sequentially changed by using the control variable method, and the drop diameter is measured after trial printing; Multiple sets of corresponding data of the printing parameters and the drop diameters are obtained to form the database. 5.The current fluid repair process of the display panel according to claim 1, wherein, The real-time imaging preliminary inspection on the liquid drops of the functional liquid falling on the defect sites by the visual imaging element comprises: The imaging direction of the visual imaging element and the imaging inclination angle θ of the plane where the defect sites are located are obtained; The visual imaging element is used to obtain the preliminary inspection image by real-time imaging on the liquid drops of the functional liquid falling on the defect sites; The actual length L and width X of the preliminary inspection image are obtained according to the preliminary inspection image; The actual first diameter D1 of the liquid drop is obtained according to the length L of the preliminary inspection image; The actual second diameter D2 of the liquid drop is obtained according to D2=X / sinθ; It is judged whether the actual first diameter D1 and the actual second diameter D2 of the liquid drop are within the preset error range of the preset drop diameter; if yes, the preliminary inspection is qualified, otherwise, the preliminary inspection is unqualified.

6. The current fluid repair process of display panel according to claim 5, wherein, The preset error range is not greater than 15%.

7. The current fluid repair process of display panel according to claim 1, characterized in that, The electro-fluid printing repair assembly comprises multiple printing heads, the multiple printing heads and the imaging module are arranged along the same line, and the multiple printing heads at least comprise the printing heads for printing the functional liquid of type 2; The defect sites on the defective substrate are sequentially placed directly below the printing head, which comprises: The multiple defect sites are sequentially placed directly below the printing head of the corresponding functional liquid type according to the defect type of the defect sites on the defective substrate.

8. The current fluid repair process of display panel according to claim 7, wherein, The incoming inspection of the defective substrate to obtain the position, size and defect type of all defect sites on the defective substrate further comprises: measuring the center-to-center distance of adjacent pads on the defective substrate along the arrangement direction of the plurality of printheads and calibrating it as a unit distance; obtaining defect sites of the same defect type on the defective substrate, and grouping the defect sites of the same defect type in each row along the arrangement direction of the plurality of printheads, wherein the number of defect sites in each group of defect sites of the same defect type does not exceed the number of printheads corresponding to the same defect type; adaptively adjusting the center-to-center distance of the plurality of printheads in real time, so that the mounting distance is an integer multiple of the unit distance, and the center-to-center distance of the plurality of printheads corresponding to the same defect type is consistent with the center-to-center distance of the plurality of defect sites of the same group of the same defect type to be repaired.

9. The current fluid repair process of display panel according to claim 8, wherein, When the number of printheads of the same defect type is greater than the number of defect sites of the same group of the same defect type to be repaired, some printheads are shielded so that the number of working printheads corresponds to the number of defect sites in the group.

10. An inkjet printing system, characterized by, comprise: a motion platform for carrying the defective substrate and moving the defective substrate in a horizontal plane; a vision system for imaging the droplets printed in real time and the droplets after printing; an electrofluidic printing repair assembly for printing functional liquid to the defect sites of the defective substrate; a control system for controlling the motion platform, the vision system and the electrofluidic printing repair assembly according to the electrofluidic repair process of the display panel of any one of claims 1 to 9.

Images