Display panel, display device, and splicing display device

Abstract

A display panel, a display device, and a splicing display device. The display panel comprises a substrate, a bridging structure, a plurality of back electrodes, and a plurality of connecting wires. The substrate comprises a first surface and a second surface which are oppositely arranged, and a plurality of first side surfaces, and at least one of the plurality of first side surfaces is a first selected side surface. The bridging structure is arranged on the second surface, the bridging structure comprises a third surface and a fourth surface which are oppositely arranged, and the third surface is close to the substrate relative to the fourth surface. The part, close to the first selected side surface, of the bridging structure is provided with a plurality of grooves, and the openings of the plurality of grooves face the first selected side surface. Each connecting wire comprises a first wire, a second wire, and a third wire, and the third wire comprises a first portion, a second portion, and a third portion which are connected in sequence. The second portion is located in the groove, the third portion is located on one side of the fourth surface and connected to the back electrode, and the first portion is located between the second portion and the second wire.

Description

Display panel, display device, and spliced ​​display device

[0001] This application claims priority to Chinese patent application No. 202310813867.8, filed on July 4, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to the field of display technology, and in particular to a display panel, a display device, and a spliced ​​display device. Background Art

[0003] The use of micro light-emitting diodes (MLDs) or sub-millimeter light-emitting diodes (MLDs) as pixels in display panels has attracted widespread attention and research. However, due to mass transfer yield issues, large-scale display devices cannot be produced in one go. Instead, a large-scale spliced ​​display device is usually assembled by splicing small-scale display devices.

[0004] In order to reduce the bezel size of the display device and reduce the seam width of the spliced ​​display device, a single display panel can currently use wiring arranged on the side of the display panel to connect the wiring on the display surface with the driver (such as a circuit board or driver chip) arranged on the non-display surface. In this way, when multiple display panels are composed to form a larger spliced ​​display device, the spacing between adjacent display panels can be smaller, thereby improving the display quality.

[0005] Summary of the Invention

[0006] In one aspect, a display panel is provided. The display panel includes a substrate, a bridge structure, multiple back electrodes, and multiple connecting traces. The substrate includes a first surface and a second surface facing each other, and multiple first side surfaces connecting the first and second surfaces, at least one of the multiple first side surfaces being a first selected side surface. The bridge structure is disposed on the second surface and includes a third surface and a fourth surface facing each other, the third surface being closer to the substrate than the fourth surface. A portion of the bridge structure stacked near the first selected side surface is provided with multiple grooves, with the openings of the multiple grooves facing the first selected side surface. Multiple back electrodes are disposed in parallel and spaced apart on the fourth surface, with each groove corresponding to a back electrode. The multiple connecting traces are arranged in parallel and spaced apart. Each connecting trace includes a first trace located on one side of the first surface, a second trace located on one side of the first selected side surface, and a third trace located on one side of the second surface. The third trace includes a first portion, a second portion, and a third portion connected in sequence. The second portion is located within the groove, the third portion is located on the fourth surface and connected to the back electrode, and the first portion is located between the second portion and the second trace.

[0007] In some embodiments, a dimension of the second portion along the first direction is smaller than dimensions of the first portion and the third portion along the first direction.

[0008] In some embodiments, the second portion includes a first sub-portion and a second sub-portion, the average distance between the second sub-portion and the second surface is greater than the average distance between the first sub-portion and the second surface, and the second sub-portion is connected to the third portion; the size of the first sub-portion in the second direction is greater than the size of the second sub-portion in the second direction, and the second direction is the extension direction of the third trace.

[0009] In some embodiments, the thickness of the first subsection is greater than or equal to the thickness of the first section, and the thickness of the first subsection is greater than the thickness of the third section.

[0010] In some embodiments, a thickness of a portion of the first portion proximate to the bridging structure is greater than a thickness of a portion of the first portion proximate to the first selected side surface.

[0011] In some embodiments, a dimension of the groove in a first direction is smaller than a dimension of the back electrode in the first direction, and the first direction is perpendicular to an extension direction of the third trace.

[0012] In some embodiments, a ratio of a size of the groove in the first direction to a size of the back electrode in the first direction ranges from 0.5 to 0.6.

[0013] In some embodiments, on a plane parallel to and perpendicular to the second direction, the groove has multiple cross-sections, and the cross-section farthest from the first selected side surface among the multiple cross-sections has a size in the first direction that is less than or equal to the size of the cross-section farthest from the first selected side surface among the multiple cross-sections in the first direction.

[0014] In some embodiments, the orthographic projection of the groove on the second surface is in the shape of a square, a trapezoid, a semicircle, or a semi-ellipse.

[0015] In some embodiments, a buffer structure is provided at a sidewall of the groove close to the back electrode, the second portion is located in the groove, and a portion of the second portion is located on the buffer structure.

[0016] In some embodiments, the groove and the corresponding back electrode have a first spacing in the second direction; and a ratio of a size of the groove in the second direction to the first spacing is in a range of 0.6 to 1.

[0017] In some embodiments, a side of the bridging structure close to the first selected side surface has a second distance from the first selected side surface in the second direction.

[0018] In another aspect, a display device is provided, comprising: a display panel according to any of the above embodiments and a driving circuit board, wherein the driving circuit board is electrically connected to the display panel and configured to drive the display panel to display an image.

[0019] In another aspect, a spliced ​​display device is provided, comprising: a plurality of spliced ​​display devices according to the above embodiments.

[0020] In another aspect, a spliced ​​display device is provided, comprising: a plurality of spliced ​​display panels according to any one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] To more clearly illustrate the technical solutions of the present disclosure, the following briefly introduces the drawings required for use in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure, and those skilled in the art can also derive other drawings based on these drawings. Furthermore, the drawings described below are schematic diagrams and are not intended to limit the actual dimensions of the products, actual processes of the methods, actual timing of signals, and the like involved in the embodiments of the present disclosure.

[0022] FIG1 is a cross-sectional structural diagram of a display panel according to some embodiments;

[0023] FIG2 is a planar structural diagram of a display panel according to some embodiments;

[0024] FIG3 is another cross-sectional structural diagram of a display panel according to some embodiments;

[0025] FIG4 is a partial top view of the structure of a display panel according to some embodiments;

[0026] FIG5 is a partial top view of the structure of a display panel according to some embodiments;

[0027] FIG6 is a partial top view of the structure of a display panel according to some embodiments;

[0028] FIG7 is another cross-sectional structural diagram of a display panel according to some embodiments;

[0029] FIG8A is another cross-sectional structural diagram of a display panel according to some embodiments;

[0030] FIG8B is a cross-sectional structural diagram of some connecting wirings of a display panel according to some embodiments;

[0031] FIG9 is another cross-sectional structural diagram of a display panel according to some embodiments;

[0032] FIG10A is a top view of a groove of a display panel according to some embodiments;

[0033] FIG10B is another top view of a groove of a display panel according to some embodiments;

[0034] FIG10C is another top view of a groove of a display panel according to some embodiments;

[0035] FIG10D is another top view of a groove of a display panel according to some embodiments;

[0036] FIG10E is another top view of a groove of a display panel according to some embodiments;

[0037] FIG10F is another top view of a groove of a display panel according to some embodiments;

[0038] FIG11A is a cross-sectional structural diagram of a display panel according to some embodiments;

[0039] FIG11B is another cross-sectional structural diagram of a display panel according to some embodiments;

[0040] FIG12 is a partial top view of the structure of a display panel according to some embodiments;

[0041] FIG13 is a cross-sectional structural diagram of a display panel according to some embodiments;

[0042] FIG14A is another cross-sectional structural diagram of a display panel according to some embodiments;

[0043] FIG14B is another cross-sectional structural diagram of a display panel according to some embodiments;

[0044] FIG15 is a planar structural diagram of a display device according to some embodiments;

[0045] FIG16 is a planar structural diagram of a display device according to some embodiments;

[0046] FIG17 is a planar structural diagram of a spliced ​​display device according to some embodiments;

[0047] FIG18 is a planar structural diagram of a display device according to some embodiments;

[0048] FIG19 is a planar structural diagram of a spliced ​​display device according to some embodiments;

[0049] FIG20A is a structural diagram corresponding to steps for preparing a display panel according to some embodiments;

[0050] FIG20B is a structural diagram corresponding to steps for preparing a display panel according to some embodiments;

[0051] FIG20C is a structural diagram corresponding to steps for preparing a display panel according to some embodiments;

[0052] FIG20D is a structural diagram corresponding to steps of manufacturing a display panel according to some embodiments;

[0053] FIG. 20E is a structural diagram corresponding to steps for preparing a display panel according to some embodiments. DETAILED DESCRIPTION

[0054] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the embodiments described are only some embodiments of the present disclosure, not all embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present disclosure.

[0055] Unless the context requires otherwise, throughout the specification and claims, the term "comprise" and its other forms, such as the third person singular form "comprises" and the present participle form "comprising", are to be interpreted as open and inclusive, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples" are intended to indicate that the particular features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the particular features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0056] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0057] When describing some embodiments, the expressions "coupled" and "connected" and their derivatives may be used. The term "connected" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. The term "coupled" indicates, for example, that two or more components are in direct physical or electrical contact. The term "coupled" or "communicatively coupled" may also refer to two or more components that are not in direct contact with each other, but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this document.

[0058] “At least one of A, B and C” has the same meaning as “at least one of A, B or C” and both include the following combinations of A, B and C: A only, B only, C only, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B and C.

[0059] “A and / or B” includes the following three combinations: A only, B only, and a combination of A and B.

[0060] The use of "adapted to" or "configured to" herein is intended to be open and inclusive language that does not exclude devices adapted or configured to perform additional tasks or steps.

[0061] Additionally, the use of “based on” is meant to be open and inclusive, as a process, step, calculation, or other action “based on” one or more stated conditions or values ​​may, in practice, be based on additional conditions or values ​​beyond those stated.

[0062] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0063] As used herein, "parallel", "perpendicular", and "equal" include the situations described and situations similar to the situations described, and the range of the similar situations is within an acceptable deviation range, wherein the acceptable deviation range is as determined by a person of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the specific quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range of approximate parallelism can be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity can also be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality can be, for example, that the difference between the two equals is less than or equal to 5% of either one.

[0064] It will be understood that when a layer or element is referred to as being on another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may be present therebetween.

[0065] Exemplary embodiments are described herein with reference to cross-sectional and / or plan views that are idealized exemplary drawings. In the drawings, the thickness of layers and the area of ​​regions are exaggerated for clarity. Therefore, variations in shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances are contemplated. Therefore, the exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include deviations in shape due to, for example, manufacturing. For example, an etched region shown as a rectangle will typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to illustrate the actual shape of regions of the device and are not intended to limit the scope of the exemplary embodiments.

[0066] In order to improve product reliability and reduce transportation and maintenance costs, a large-size display device can be assembled by splicing multiple small-size display devices.

[0067] To avoid the sense of fragmentation in the display caused by splicing, it is necessary to reduce the bezel size of a single small-sized display device and reduce the width of the splicing seam. The small-sized display device includes a display panel. For example, side wiring can be used to connect the wiring located on the display surface side of the display panel to a circuit board (such as a flexible circuit board) provided on the non-display surface side of the display panel. Therefore, when multiple small-sized display devices are spliced ​​together to form a larger large-sized display device, the spacing between adjacent small-sized display devices can be smaller, thereby reducing the width of the splicing seam of the large-sized display device formed by splicing multiple small-sized display devices and improving the display quality.

[0068] The display panel, display device and spliced ​​display device provided by the present disclosure are introduced below respectively.

[0069] In the present disclosure, Figure 1 is a cross-sectional structural diagram of a display panel according to some embodiments, Figure 2 is a planar structural diagram of a display panel according to some embodiments, and Figure 3 is another cross-sectional structural diagram of a display panel according to some embodiments. In order to facilitate a clear description of the structural changes of the display panel during the preparation process, Figures 4 to 6 illustrate partial top-view structural diagrams of the display panel, Figures 7 to 9, Figure 11A, Figure 11B, Figure 12, Figure 13, Figure 14A and Figure 14B are cross-sectional structural diagrams of the display panel according to some embodiments, Figures 10A to 10F and Figure 12 are top-view structural diagrams of the groove of the display panel according to some embodiments, Figures 15, 16 and 18 are planar structural diagrams of the display device 100 according to some embodiments, Figures 17 and 19 are planar structural diagrams of the spliced ​​display device 200 according to some embodiments, and Figures 20A to 20E are structural diagrams corresponding to the preparation steps of the display panel according to some embodiments.

[0070] In some embodiments, as shown in FIG1 , a display panel 10 includes a substrate 1, a plurality of front electrodes 2, a plurality of connecting traces 3, and a plurality of back electrodes 4. The substrate 1 includes a first surface 1a and a second surface 1b relative to each other, and a plurality of first side surfaces 1c connecting the first surface 1a and the second surface 1b. At least one of the plurality of first side surfaces 1c of the substrate 1 is a first selected side surface 1cc. A plurality of connecting traces 3 are provided corresponding to each first selected side surface 1cc, and the plurality of connecting traces 3 are arranged in parallel and spaced apart. Each connecting trace 3 extends from the first surface 1a through the first selected side surface 1cc to the second surface 1b. In other words, each connecting trace 3 includes a first trace 31 located on one side of the first surface 1a, a second trace 32 located on one side of the first selected side surface 1cc, and a third trace 33 located on one side of the second surface.

[0071] Exemplarily, as shown in Figures 1 and 2, one side of the first surface 1a of the substrate 1 is the front of the display panel 10, and a display area AA and a binding area BB are provided on one side of the first surface 1a of the substrate. A film structure such as a driving circuit layer and a light-emitting device layer 5 is provided in the display area AA. The light-emitting device layer 5 includes light-emitting devices 51 of at least three colors, and the light-emitting devices of multiple colors include at least a first color light-emitting device 511, a second color light-emitting device 512 and a third color light-emitting device 513, wherein the first color, the second color and the third color are three primary colors (for example, red, green and blue). Exemplarily, the light-emitting device 51 is a Micro LED (Micro Light Emitting Diode) and a Mini LED (Mini Light Emitting Diode).

[0072] As shown in Figures 1 and 2, one side of the first surface 1a of the substrate 1 is the front of the display panel 10, and a plurality of front electrodes 2 can be arranged in the binding area BB and arranged in parallel and spaced apart along the first direction X, where the first direction X is a direction parallel to the boundary line between the first selected side surface 1cc and the first surface 1a. The plurality of front electrodes 2 are electrically connected to at least a portion of the drive circuit layer (not shown in the figure). The first traces 31 of the plurality of connecting traces 3 are located on the side of the first surface 1a of the substrate 1 and are electrically connected to the plurality of front electrodes 2 in a one-to-one correspondence. The extension direction of the first traces 31 of the plurality of connecting traces 3 is, for example, a direction perpendicular to the first selected side surface 1cc of the substrate 1, that is, the second direction Y shown in Figure 1.

[0073] For example, with continued reference to FIG. 1 , the second surface 1b of the substrate 1 is the back side of the display panel 10, and the third traces 33 of the plurality of connecting traces 3 are located on the second surface 1b side of the substrate 1. In other words, the third traces 33 of the plurality of connecting traces 3 are the portion of the connecting traces 3 located on the back side of the display panel 10. The third traces 33 of the plurality of connecting traces 3 extend in, for example, the second direction Y. A plurality of back electrodes 4 are disposed on the second surface 1b side of the substrate and are arranged in parallel and spaced relation along the first direction X. The plurality of back electrodes 4 can serve as binding electrodes for connecting to a flexible circuit board, and the third traces 33 of the plurality of connecting traces 3 are electrically connected to the plurality of back electrodes 4 in a one-to-one correspondence.

[0074] The method for manufacturing the display panel 10 includes forming a drive circuit layer on a first surface 1a of a substrate 1, the drive circuit layer including a plurality of front electrodes 2; and forming a plurality of back electrodes 4 on a second surface 1b of the substrate 1. The drive circuit layer may be formed by, for example, etching, and the back electrodes 4 may be formed by, for example, laser etching.

[0075] In this case, both the first surface 1a and the second surface 1b of the substrate 1 need to be etched, resulting in high manufacturing costs for the display panel 10. Furthermore, if the orthographic projections of the multiple back electrodes 4 on the substrate 1 overlap with the area corresponding to the display area AA, the laser light may pass through the substrate 1 and enter the display area AA of the first surface 1a. Consequently, some of the laser light energy may pass through the substrate 1 and reach the display area AA, potentially damaging the film layers and devices within the display area AA, leading to reliability issues such as localized corrosion and the failure of the light-emitting device to illuminate.

[0076] In other examples, during the production process of substrate 1, the devices on the front side of the substrate are prepared first, and then the devices on the back side of the substrate are prepared through a flipping process. During the flipping process of the substrate, the substrate contact equipment is easily scratched and contaminated, and static electricity cannot be released, affecting the yield and quality of the product.

[0077] Therefore, in order to reduce the manufacturing cost of the display panel 10 and avoid the influence of the back surface process of the substrate 1 on the front surface film layer and the device, in some embodiments, as shown in Figures 1 and 3, the display panel 10 also includes a bridging structure 6 arranged on the second surface 1b of the substrate 1; the bridging structure 6 includes a third surface 6a and a fourth surface 6b arranged opposite to each other, and a plurality of second side surfaces 6c connecting the third surface 6a and the fourth surface 6b; the third surface 6a is close to the substrate 1 relative to the fourth surface 6b; at least one second side surface 6c among the plurality of second side surfaces 6c is a second selected side surface 6cc; each second selected side surface 6cc corresponds to a first selected side surface 1cc.

[0078] As shown in Figure 1, by providing a bridging structure 6 on the second surface 1b of the substrate 1, the bridging structure 6 can serve as a carrier of multiple back electrodes 4. In the case where the display panel 10 includes a bridging structure 6, the formation of multiple back electrodes 4 can be achieved through the following two steps: first, multiple back electrodes 4 are formed on the fourth surface 6b of the bridging structure 6, and then the bridging structure 6 is connected to the second surface 1b of the substrate 1 with high precision, so that the second surface 1b of the substrate 1 is in contact with the third surface 6a of the bridging structure 6, and at the same time, the front electrode 2 and the back electrode 4 are facing each other in the third direction Z. The above-mentioned process of connecting the bridging structure 6 to the second surface 1b of the substrate 1 with high precision is, for example, bonding. Through the above method, costs can be reduced while avoiding the influence of the etching process on the front film layer and the device.

[0079] In some embodiments, as shown in Figure 1, the back electrode 4 includes a first end 41 close to the first selected side surface 1cc, and a second end 42 away from the first selected side surface 1cc, wherein the first end 41 is used to connect the trace 3, for example, the connecting trace is overlapped on the first end 41, and the second end is used to connect to the circuit board or the flexible circuit board, for example, the circuit board or the flexible circuit board is overlapped on the second end 42.

[0080] Illustratively, the bridge structure 6 may further include an insulating layer 9 located on a side of the fourth surface of the back electrode 4 away from the bridge structure, wherein the insulating layer 9 exposes at least the first end 41 and the second end 42 of each back electrode 4 .

[0081] The insulating layer covers the middle portion of the back electrode to protect the back electrode and prevent the back electrode from being corroded. The insulating layer exposes the first end and the second end of each back electrode to connect the back electrode to the wiring and the circuit board / flexible circuit board.

[0082] It should be noted that each of the above-mentioned second selected side surfaces 6cc corresponds to one first selected side surface 1cc, which means that the number of second selected side surfaces 6cc and first selected side surfaces 1cc corresponds, and the second selected side surface 6cc is close to the corresponding first selected side surface 1cc, and the two are arranged along the third direction Z.

[0083] In some embodiments, as shown in Figures 1 and 3, when the display panel 10 includes a bridging structure 6, the third trace 33 of the connecting trace 3 extends from the second surface 1b of the substrate 1 to the fourth surface 6b of the bridging structure 6, that is, the third trace 33 is arranged on the second selected side surface 6cc and the fourth surface 6b of the bridging structure 6, and is electrically connected to the second electrode 4.

[0084] The preparation process for the plurality of connecting traces 3 is as follows: a second trace 32, a first trace 31, and a third trace 33 are formed on the first selected side surface 1cc of the substrate 1, the first surface 1a of the substrate 1, and the second surface 1b of the substrate 1, respectively. For example, a printing process is used to form a conductive paste in a printing device on the areas corresponding to the areas where the connecting traces need to be printed. For example, the conductive paste is sequentially formed on the first surface 1a, the first selected side surface 1cc, the second surface 1b, the second selected side surface 6cc, and the fourth surface 6b of the substrate 1. The printing process may be, for example, a three-dimensional printing process, and the conductive paste may be, for example, silver paste. The three-dimensional printing process uses a needle with a certain caliber and air pressure to squeeze the conductive paste in the needle tube onto a specific position on the substrate. After the conductive paste solidifies, the traces are formed. Since the connecting trace 3 includes parts located on different surfaces, each connecting trace needs to be formed separately by printing in batches. For example, it can be printed in three batches to form a part located on the first surface 1a, a part located on the first selected side surface 1cc, and a part located on the second surface 1b, the second selected side surface 6cc, and the fourth surface 6b. Exemplarily, the printing process is as follows: the substrate is set on the substrate carrier, the substrate carrier moves along the second direction Y (moves left and right), the printing needle P is set along the third direction Z, and the position is kept fixed in the second direction Y. The printing needle moves in the third direction Z (moves up and down), and the ejection speed of the printing needle P remains constant. By controlling the movement speed of the substrate carrier in the second direction Y and the movement speed of the printing needle P in the third direction X, the distance between the printing needle and the substrate surface is controlled to achieve the conductive paste being written on the substrate surface. After curing, a connecting trace with a relatively uniform width and thickness is formed, and a good climbing morphology is provided at the step difference of the bridge structure.

[0085] There are certain difficulties in the process of forming the portion of the connecting traces located on the second surface 1b, the second selected side surface 6cc and the fourth surface 6b by printing. On the one hand, since the conductive paste has a certain fluidity, when the substrate carrier moves slowly, it is easy to cause the conductive paste to accumulate, making the final formed traces wider. After the printing is completed, the distance between two adjacent traces in the first direction X is too close, which is easy to short-circuit, causing a short circuit. For example, as shown in Figure 3, in the process of forming the portion of the connecting traces located on the second surface 1b, the second selected side surface 6cc and the fourth surface 6b by printing, the printing needle P is always placed parallel to the third direction Z. The relative movement path of the printing needle P and the substrate carrier is indicated by the dotted arrow. A specific position on the second surface 1b of the substrate 1 is used as the starting printing position. The printing needle P is located above the starting position and starts printing. The printing needle maintains a constant coating speed and continues to spit out the material. The substrate carrier moves a specific distance to the left (F1 direction) along the second direction Y, so that the printing needle P moves relatively from the starting position to the bridge structure 6 close to the first selected After the end face of the side surface 1cc is reached, the substrate carrier continues to move in the F1 direction. At this time, the print head P slowly moves upward along the third direction Z (along the F2 direction) so that the print head P moves to print directly above the fourth surface 6b of the bridging structure 6. That is to say, during the process of the print head P printing from the end face close to the first selected side surface 1cc to directly above the fourth surface 6b of the bridging structure 6, the relative movement path of the print head P and the substrate carrier is as indicated by the dotted arrow. After that, the print head P continues to maintain this position for printing, and the substrate 1 continues to move a specific distance relative to the print head P in the F1 direction until printing is completed, and the print head P is closed. Since the bridging structure has a certain thickness and there is a large step difference between the second surface and the fourth surface, in order to ensure that the conductive paste will not break after curing, when printing to the step difference position, the movement speed of the substrate carrier along the second direction Y slows down, so that the printing needle stays longer. Therefore, the conductive paste will accumulate at this position, and after the conductive paste is cured, the risk of contact between the two adjacent connecting lines 3 at this position is greatly increased, which can easily cause a short circuit between the two adjacent connecting lines 3, thereby affecting the reliability of the display panel.

[0086] On the other hand, referring to Figure 3, when the second selected side surface 6cc of the bridging structure 6 is perpendicular to the second surface 1b, in the process of forming multiple connecting traces 3, since the fourth surface 6b of the bridging structure 6 and the second surface 1b of the substrate 1 are not on the same horizontal plane, the two constitute a step structure, and the size of the second selected side surface 6cc in the third direction Z is larger than the discharge thickness of the printing needle. Therefore, it is more difficult to set the conductive paste on the second surface 1b by printing. At the same time, due to the influence of gravity and the leveling characteristics of the conductive paste, the conductive paste will accumulate at the bottom of the step position, but it may still be thin at the junction of the second selected side surface 6cc and the fourth surface 6b. At the same time, since the conductive paste will deform during the curing process, such as volume shrinkage, the formed connecting traces 3 are prone to breakage at the junction of the second selected side surface 6cc and the fourth surface 6b, which in turn causes the circuit of the display product to be broken, causing the display panel to be unable to display.

[0087] The thickness of the material ejected by the printing needle is the thickness of the conductive paste printed on the second selected side surface in the third direction. Exemplarily, the ratio of the thickness of the material ejected by the printing needle to the thickness of the bridge structure in the third direction is 1:20 to 1:10. For example, if the ratio of the thickness of the material ejected by the printing needle to the thickness of the bridge structure in the third direction is 1:20 or 1:10, the thickness of the material ejected by the printing needle is 5 μm.

[0088] 4 to 6 , a plurality of grooves 61 are provided in a portion of the bridging structure 6 close to the first selected side surface 1cc, and the openings of the plurality of grooves 61 face the first selected side surface 1cc; a plurality of back electrodes 4 are arranged in parallel and spaced apart on the fourth surface 6b.

[0089] It can be understood that, as shown in Figure 3, the grooves are arranged in the portion of the bridging structure 6 close to the first selected side surface 1cc, and the openings of the multiple grooves 61 are toward the first selected side surface 1cc, that is, from the top view of the display panel, the grooves 61 are recessed from the second selected side surface 6cc toward the second electrode, and from the side view of the display panel, the grooves 61 are recessed from the fourth surface 6b toward the third surface 6a.

[0090] Exemplarily, the thickness of the bridging structure 6 in the third direction Z is 100 μm to 150 μm, and the third direction Z is the thickness direction of the substrate 1 .

[0091] For example, the material of the bridge structure 6 may be glass, polyimide (PI, Polyimide Film) or other materials.

[0092] In some examples, as shown in FIG. 3 , the groove 61 is arranged to extend from the fourth surface 6 b to the third surface 6 a in the third direction Z. That is, the thickness of the groove 61 in the third direction Z is the same as the thickness of the bridging structure 6 in the third direction Z.

[0093] Exemplarily, the groove 61 runs through the entire bridge structure 6 , and the bottom of the groove 61 exposes the second surface 1 b of the substrate 1 .

[0094] In other examples, as shown in Figure 4, the groove 61 is set to pass through a portion of the bridging structure 6 along the fourth surface 6b in the third direction Z. At this time, the thickness of the groove 61 in the third direction Z is less than the thickness of the bridging structure 6 in the third direction Z.

[0095] Exemplarily, the groove 61 partially penetrates the bridging structure 6 , and the bottom of the groove 61 does not expose the second surface 1 b of the substrate 1 .

[0096] In some embodiments, each surface of the groove 61 is parallel to the third direction Z. That is, each surface of the groove 61 is perpendicular to the second surface 1 b of the substrate 1 .

[0097] In other embodiments, the bottom surface of the groove 61 may have a certain angle with the third direction Z, and the angle range is 30° to 60°. The bottom surface of the groove is the surface close to the back electrode, and the bottom surface of the groove has an angle with the third direction. The angle is 30° to 60°, that is, an obtuse angle is formed between the bottom surface of the groove and the second surface 1b of the substrate. The bottom surface of the groove is an inclined surface. In this way, during the printing process, the path from the second surface to the fourth surface through the bottom surface of the groove is smoother, the printing difficulty is reduced, and the connection line can be further prevented from breaking.

[0098] In some embodiments, as shown in Figures 1 and 6, when the display panel 10 includes a bridging structure 6, the third routing line 33 of the connecting routing line 3 includes a first portion 331, a second portion 332 and a third portion 333 connected in sequence, wherein the second portion 332 is located in the groove 61, the third portion 333 is located on one side of the fourth surface 6b and is electrically connected to the back electrode 4, and the first portion 331 is located between the second portion 332 and the second routing line 32.

[0099] 7 , a groove 61 is formed in a portion of the bridging structure 6 near the first selected side surface 1cc, and the second portion 332 of the third trace 33 is located within the groove 61. That is, during the printing of the second portion 332, the conductive paste is formed within the groove 61. The groove 61 can limit the boundary of the conductive paste forming the second portion 332 to a certain extent, thereby preventing the conductive paste from diffusing to both sides along the first direction X. As the movement speed of the substrate carrier slows down, it is easy to cause material accumulation in the groove. However, since the conductive paste is subject to certain restrictions in the first direction X, the conductive paste can only be accumulated along the third direction Z. That is to say, the thickness of the conductive paste in the third direction Z gradually increases. When the printing needle P moves from the opening of the groove to the end, the conductive paste (as shown in FIG8B corresponding to the first sub-portion 332a) has filled the bottom of the groove and has a certain thickness, forming a step. When the printing needle P moves slowly along the third direction Z and continues to print the conductive paste located on the side wall of the groove close to the second electrode (as shown in FIG8B corresponding to the second sub-portion 332b), it is equivalent to continuing to print the conductive paste upward on the basis of the conductive paste that has filled the bottom of the groove. The step difference from the first step to the fourth surface is reduced, which reduces the difficulty of printing and makes the distribution of the conductive paste more uniform. Compared with the case where the groove 61 is not provided, a groove is provided on the bridging structure, so that the conductive paste can be formed in batches at the step difference during the process of printing and forming the second part 332, which is equivalent to reducing the vertical height that needs to be formed in a single time, and the larger step difference is decomposed into two smaller steps in the third direction Z. The conductive paste is easier to print on the bridging structure, and the thickness of the conductive paste is thickened at the junction of the second selected side surface 6cc and the fourth surface 6b, thereby avoiding the problem of breakage of the conductive paste during the curing process due to the large step difference. At the same time, since the second part is confined in the groove and does not overflow, the short circuit between the second parts 332 of the two adjacent connecting lines 3 is avoided.

[0100] As shown in Figure 5, when the groove 61 passes through part of the bridging structure 6 along the third direction Z and the bottom of the groove 61 does not expose the second surface 1b of the substrate 1, a first step is formed between the bottom of the groove 61 and the second surface of the substrate, and a second step is formed between the bottom of the groove 61 and the fourth surface 6b of the bridging structure 6, decomposing the larger step difference between the second surface 1b and the fourth surface 6b into two smaller step differences. During the printing process, the conductive paste is smeared from the second surface 1b through the first step with a smaller step difference on the bottom of the groove 61. After filling the bottom of the groove 61, it continues to pass through the second step and is smeared on the fourth surface 6b. Since the groove 61 does not completely pass through the bridging structure, the step difference between the bottom of the groove 61 and the fourth surface of the bridging structure 6 is reduced. When the conductive paste is formed in the groove, the conductive paste accumulates and raises, further reducing the step difference between the surface of the conductive paste and the fourth surface 6b, thereby reducing the difficulty of printing the conductive paste on the side wall of the groove 61, so that the formed connecting trace 3 is not easy to break.

[0101] In some embodiments, referring to FIG. 6 , a dimension d2 of the second portion 332 along the first direction X is smaller than dimensions of the first portion 331 and the third portion 333 along the first direction X.

[0102] It can be understood that, referring to Figure 6, the size of the first portion 331 in the first direction X is d1, and the size of the third portion 333 in the first direction X is d3. Referring to the aforementioned content, it can be seen that during the printing process, the conductive paste is applied to the second surface 1b and the fourth surface 6b. Since the conductive paste has a certain fluidity, the conductive paste will level along the first direction X. Finally, after curing, the first portion 331 and the third portion 333 have larger sizes in the first direction X. Since the second portion 332 is located inside the groove 61, it is equivalent to limiting the size d2 of the second portion 332 in the first direction X. Therefore, the size d2 of the second portion 332 along the first direction X is narrowed to a certain extent. Therefore, the size d2 of the second portion 332 along the first direction X is smaller than the sizes of the first portion 331 and the third portion 333 along the first direction X, that is, d2<d1 / d3. In this way, even if the conductive paste accumulates in the groove 61 , the size of the second portion 332 in the first direction X will not be too large due to the limitation of the groove sidewall, thereby preventing two adjacent third portions 333 from short-circuiting.

[0103] In some embodiments, as shown in Figures 7, 8A and 8B, the second portion 332 includes a first sub-portion 332a and a second sub-portion 332b, the average distance s2 between the second sub-portion 332b and the second surface 1b is greater than the average distance s1 between the first sub-portion 332a and the second surface 1b, and the second sub-portion 332b is connected to the third portion 333, and the first sub-portion 332a is connected to the first portion 331; the dimension d4 of the first sub-portion 332a in the second direction Y is greater than the dimension d5 of the second sub-portion 332b in the second direction Y, and the second direction Y is the extension direction of the third trace 33.

[0104] It should be noted that, referring to Figures 7, 8A and 8B, the average distance s1 between the second sub-portion 332b and the second surface 1b shown in the figures refers to the average value of the distance between the side of the second sub-portion 332b away from the second surface 1b and the second surface 1b, and the average distance s1 between the first sub-portion 332a and the second surface 1b is the average value of the distance between the side of the first sub-portion 332a away from the second surface 1b and the second surface 1b. The average distance s2 between the second sub-portion 332b and the second surface 1b is greater than the average distance s1 between the first sub-portion 332a and the second surface 1b, that is, the second sub-portion 332b is farther away from the second surface 1b than the first sub-portion 332a, and the first sub-portion 332a is located at the bottom of the groove 61, and the second sub-portion 332b is located above the first sub-portion 332a and contacts the side wall of the groove 61.

[0105] Exemplarily, referring to Figures 8A and 8B, the dimension d4 of the first sub-portion 332a in the second direction Y, the dimension d5 of the second sub-portion 332b in the second direction Y, the dimension d4 of the first sub-portion 332a in the second direction Y is greater than the dimension d5 of the second sub-portion 332b in the second direction Y. According to Figures 8A and 8B, in the cross-sectional views shown in Figures 8A and 8B, the second portion 332 formed by the first sub-portion 332a and the second sub-portion 332b is stepped.

[0106] In some embodiments, as shown in FIG. 8A and FIG. 8B , the thickness t2 of the first sub-portion 332 a is greater than or equal to the thickness t1 of the first portion 331 , and the thickness t2 of the first sub-portion 332 a is greater than the thickness t3 of the third portion 333 .

[0107] It can be understood that, referring to Figures 8B and 9, the first part 331 located on the second surface 1b in the figure includes two parts, namely a straight part 331a and a sloped part 331b, the thickness of the straight part 331a and the sloped part 331b are not equal, the thickness t1 of the first part 331 is the average value of the thickness at each position of the first part, the straight part 331a of the third trace 33 located on the second surface 1b and the third part 333 located on the fourth surface 6b are both formed without climbing, while the second part 332 of the third trace 33 is formed in a climbing state. In the process of forming the first sub-part 332a, due to the greater difficulty in printing and the slower movement speed of the substrate carrier, more conductive paste accumulates at this position, and the thickness t2 of the first sub-part 332a formed at this position is greater than the thickness t1 of the first part 331 and the thickness t3 of the third part 333.

[0108] In addition, referring to Figure 9, the slope portion 331b located on the second surface 1b in the figure is connected to the first sub-portion 332a. During the printing process of the slope portion 331b, it is necessary to climb the slope. Similarly, the movement speed of the substrate carrier gradually slows down, causing the accumulation of conductive paste, thereby forming the slope portion 331b shown in Figure 9, wherein the thickness t2 of the first sub-portion 332a is equal to the thickness of the portion of the slope portion close to the first sub-portion 332a, that is, the portion where the slope portion of the first portion contacts the first sub-portion forms a connection transition.

[0109] In some embodiments, as shown in FIG. 9 , a thickness t12 of a portion of the first portion 331 close to the bridge structure 6 is greater than a thickness t11 of a portion of the first portion 331 close to the first selected side surface 1 cc.

[0110] For example, referring to FIG. 9 , as previously described, the first portion 331 includes two parts: a straight portion 331a and a sloped portion 331b. The sloped portion 331b is located near the bridge structure 6, while the straight portion 331a is located near the first selected side surface 1cc. As described in the aforementioned printing process, during the formation of the sloped portion 331b, more conductive paste accumulates, corresponding to the initial ramp position. During the formation of the straight portion 331a, no ramping occurs, resulting in a thickness t12 of the sloped portion 331b greater than that of the straight portion 331a. These thicknesses are the average thicknesses of the portion of the first portion 331 on the corresponding second surface 1b, and are oriented in the third direction Z.

[0111] In some embodiments, referring to FIG. 10A , FIG. 10C and FIG. 10E , a dimension L1 of the groove 61 in the first direction X is smaller than a dimension L2 of the back electrode 4 in the first direction X, and the first direction X is perpendicular to the extension direction of the third trace 33 .

[0112] It can be understood that, according to the aforementioned content and in combination with Figure 9, in the process of printing the third trace of the connecting trace 3, since the fourth surface 6b of the bridging structure 6 and the second surface 1b of the substrate 1 are not in the same horizontal plane, the two constitute a step structure, and the size of the second selected side surface 6cc in the third direction Z is greater than the spitting thickness of the printing needle. Therefore, it is more difficult to set the conductive paste on the second surface 1b by printing. At the same time, due to the influence of gravity and the leveling characteristics of the conductive paste, the conductive paste will accumulate at the bottom of the step position, but it may still be thin at the junction of the second selected side surface 6cc and the fourth surface 6b. At the same time, since the conductive paste will deform during the curing process, such as volume shrinkage, the formed connecting trace 3 will be The junction of the surface 6b is prone to fracture. In order to avoid the fracture of the third trace 33 of the connecting trace 3 and reduce the difficulty of the conductive paste climbing during the printing process, the printing method is changed to segmented climbing printing, and the size L1 of the groove 61 in the first direction X is set to be smaller than the size L2 of the back electrode 4 in the first direction X. In the process of printing the second part 332, as the movement speed of the substrate carrier slows down, the conductive paste is restricted by the groove 61 and can only be accumulated along the third direction Z, that is, the thickness of the second part 332 in the third direction Z is increased, which can decompose the step difference between the bridging structure 6 and the second surface 1b into multiple small step differences to a certain extent, reduce the difficulty of printing, and thus avoid the fracture of the formed connecting trace 3 at the junction of the second selected side surface 6cc and the fourth surface 6b.

[0113] It should be noted that the dimension L1 of the groove 61 in the first direction X is an average dimension of the groove 61 in the first direction X.

[0114] In some embodiments, with continued reference to FIG. 10A , FIG. 10C , and FIG. 10E , a ratio of a dimension L1 of the groove 61 in the first direction X to a dimension L2 of the back electrode 4 in the first direction X ranges from 0.5 to 0.6.

[0115] It is understood that when the difference between the dimension L1 of the groove 61 in the first direction X and the dimension L2 of the back electrode 4 in the first direction X is too large, the dimension of the groove 61 is too narrow, making the dimension of the second portion too narrow, which may affect the electrical signal transmission efficiency of the connecting trace 3, thereby affecting the display of the display panel; if the difference between the dimension L1 of the groove 61 in the first direction X and the dimension L2 of the back electrode 4 in the first direction X is too small, then during the actual printing of the connecting trace 3, the stacking effect will not be obvious, and the effect of reducing the step difference cannot be achieved. By setting the ratio range of the dimension L1 of the groove 61 in the first direction X and the dimension L2 of the back electrode 4 in the first direction X, the difference between the dimension L1 of the groove 61 in the first direction X and the dimension L2 of the back electrode 4 in the first direction X can be maintained within a reasonable range, ensuring the transmission efficiency of the electrical signal of the display panel, thereby improving the yield of the display panel. Exemplarily, the ratio range of the dimension L1 of the groove 61 in the first direction X to the dimension L2 of the back electrode 4 in the first direction X is, for example, 0.5, 0.55 or 0.6.

[0116] In some embodiments, referring to Figures 10A to 10F, on a plane parallel to and perpendicular to the second direction Y, the groove 61 has multiple cross-sections, and the cross-section farthest from the first selected side surface 1cc among the multiple cross-sections has a dimension L11 in the first direction X that is less than or equal to the dimension L12 in the first direction X of the cross-section closest to the first selected side surface 1cc among the multiple cross-sections.

[0117] For example, referring to Figure 10A, the dimension L11 of the cross-section farthest from the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X is equal to the dimension L12 of the cross-section closest to the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X, and the positive projection of the groove 61 on the second surface 1b is a rectangle. It can be understood that, according to the above content and in combination with Figure 9, in the process of printing the second part 332 located in the groove 61, due to the difficulty in climbing, the movement speed of the substrate carrier will slow down, which results in the conductive paste at the position farthest from the first selected side surface 1cc of the groove 61. The accumulation degree of the conductive paste is higher than the accumulation degree of the conductive paste at the position closest to the first selected side surface 1cc of the groove 61. That is, the thickness of the second part 332 formed at the position farthest from the first selected side surface 1cc of the groove 61 in the third direction Z is greater than the thickness of the second part 332 at the position closest to the first selected side surface 1cc of the groove 61 in the third direction Z. At this time, the second part 332 is perpendicular to the second selected side surface 6cc. The orthographic projection of the plane is a step shape, which is equivalent to reducing the difficulty of climbing once, decomposing the height difference between the second surface 1b and the fourth surface 6b into multiple small steps, achieving multiple climbing, and avoiding the problem of breakage due to the large height difference during the curing process of the conductive paste. At the same time, due to the limitation of the position of the groove 61 in the first direction X, the size of the conductive paste in the first direction X will not become wider, which can avoid the short circuit phenomenon of two adjacent connecting lines 3 in the local area.

[0118] For example, referring to Figures 10C to 10F and the description in the foregoing part, since the fourth surface 6b of the bridging structure 6 and the second surface 1b of the substrate 1 are not on the same horizontal plane, the two constitute a step structure. The step difference from the second surface 1b to the fourth surface 6b is large, making it difficult for the conductive paste to climb upright on the second selected side surface 6cc, increasing the difficulty of printing. The dimension L11 of the section farthest from the first selected side surface 1cc among the multiple cross sections of the groove 61 in the first direction X is smaller than the dimension L12 of the section closest to the first selected side surface 1cc among the multiple cross sections of the groove 61 in the first direction X. For example, the dimension of the groove 61 gradually narrows along the direction from the first selected side surface 1cc to the second selected side surface 6cc. During the printing process of the substrate carrier moving, the conductive paste can be accumulated faster at a position far from the first selected side surface 1cc in the groove 61 than at a position close to the first selected side surface 1cc in the groove 61 under the same speed of the substrate carrier moving. The height of the accumulated conductive paste is also higher, which not only improves the printing efficiency, but also It is easier to prepare the stepped second portion 332, and the thickness of the formed second portion 332 at the position of the groove 61 away from the first selected side surface 1cc in the third direction Z is greater than the thickness of the second portion 332 at the position of the groove 61 close to the first selected side surface 1cc in the third direction Z, which is equivalent to further reducing the difficulty of climbing once, decomposing the height difference between the second surface 1b and the fourth surface 6b into multiple small sections, achieving multiple climbing, and avoiding the problem of fracture due to large height difference during the curing process of the conductive paste. At the same time, due to the limitation of the position of the groove 61 in the first direction X, the size of the conductive paste in the first direction X will not widen, which can avoid the short circuit phenomenon of two adjacent connecting lines 3 in the local area.

[0119] In some embodiments, referring to FIG. 10A to FIG. 10F , the orthographic projection of the groove 61 on the second surface 1 b is in the shape of a square, a trapezoid, or a semi-ellipse.

[0120] Exemplarily, referring to Figure 10A, the shape of the positive projection of the groove 61 on the second surface 1b is a square, which can ensure that the dimension L11 of the cross-section farthest from the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X is equal to the dimension L12 of the cross-section closest to the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X, and has the same beneficial effects as the above-mentioned embodiments, which will not be repeated here.

[0121] Exemplarily, referring to Figures 10C to 10F, the shape of the positive projection of the groove 61 on the second surface 1b is a trapezoid or a semi-ellipse, respectively, which can ensure that the dimension L11 of the section farthest from the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X is smaller than the dimension L12 of the section closest to the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X, and the dimension of the groove 61 in the first direction gradually narrows along the direction from the first selected side surface 1cc to the second selected side surface 6cc. In this way, during the relative movement of the printing needle P to print the conductive paste, the accumulation speed of the conductive paste in the groove 61 gradually accelerates, and the height of the conductive paste accumulation gradually becomes higher, which is equivalent to forming a gentle slope, reducing the difficulty of printing, making the formed third part more reliable, and having the same beneficial effects as the above-mentioned embodiments, which are not elaborated here.

[0122] In some embodiments, referring to FIG. 11A and FIG. 11B , a buffer structure 7 is provided at a sidewall of the groove 61 close to the back electrode 4 , the second portion 332 is located in the groove 61 and a portion of the second portion 332 is located on the buffer structure 7 .

[0123] It should be noted that the thickness of the buffer structure 7 near the side wall of the back electrode 4 in the third direction Z is less than or equal to the thickness of the groove 61 in the third direction Z, so as to ensure that the second part 332 of the connecting line 3 can climb slowly while printing, reducing the difficulty of climbing.

[0124] For example, referring to Figure 10A, the thickness of the portion of the buffer structure 7 at the side wall close to the back electrode 4 in the third direction Z is less than the thickness of the groove 61 in the third direction Z. The buffer structure 7 is located in the groove 61, and the buffer structure 7 is close to one side of the back electrode 4. The provision of the buffer structure 7 is equivalent to constructing a gentle slope inside the groove 61 before the second part 332 of the connecting trace 3 is printed, which to a certain extent decomposes the height difference between the second surface 1b and the fourth surface 6b. The second part 332 in the groove 61 can achieve slow climbing through the buffer structure 7, thereby avoiding the problem of breakage due to the large height difference during the curing process of the conductive paste.

[0125] For example, referring to Figure 10B, the thickness of the portion of the side wall of the buffer structure 7 close to the back electrode 4 in the third direction Z is equal to the thickness of the groove 61 in the third direction Z, that is, the thickness of the portion of the side wall of the buffer structure 7 close to the back electrode 4 in the third direction Z is equal to the thickness of the bridging structure 6 in the third direction Z. In the process of printing the second part 332 of the connecting trace 3, the conductive paste can be evenly printed along the side of the buffer structure 7 away from the substrate 1, and in the process of continuing to print the third part 333, since there is no height difference between the second part 332 and the third part 333, the printing equipment can maintain a smooth transition printing at a height, and at the same time, it can avoid the connection trace 3 formed due to the height difference. The phenomenon of breakage is eventually caused.

[0126] In some embodiments, the material of the buffer structure 7 includes an organic material.

[0127] For example, the material of the buffer structure 7 may be resin or polyimide.

[0128] In some embodiments, referring to FIG. 12 , the groove 61 and the corresponding back electrode 4 have a first spacing H1 in the second direction Y; a ratio of a dimension H2 of the groove 61 in the second direction Y to the first spacing H1 is in a range of 0.6-1.

[0129] Exemplarily, as shown in Figure 12, the groove 61 and the corresponding back electrode 4 are provided with a first spacing H1 in the second direction Y. That is, referring to Figure 9, the fourth surface 6b of the bridging structure 6 and the side of the back electrode 4 away from the bridging structure 6 form a certain height difference, which is equivalent to a buffer step. The main purpose is to ensure that in the process of printing the second part 332 of the connecting trace 3, the height difference is only the thickness of the bridging structure 6 in the third direction Z; if the groove 61 and the corresponding back electrode 4 have no spacing in the second direction Y, that is, the side of the back electrode 4 close to the second selected side surface 6cc coincides with the side of the groove 61 away from the second selected side surface 6cc, in the process of printing the second part 332 of the connecting trace 3, the height difference becomes the sum of the thickness of the bridging structure 6 in the third direction Z and the thickness of the back electrode 4 in the third direction Z. The height difference is larger, which is not conducive to the printing of the connecting trace 3. The part where the second part 332 and the third part 333 of the connecting trace 3 are connected is more likely to break. Therefore, the groove 61 and the corresponding back electrode 4 are provided with a first spacing H1 in the second direction Y to avoid the above problem.

[0130] It is understood that setting a range of ratios between the dimension H2 of the groove 61 in the second direction Y and the first spacing H1 can ensure that the conductive paste leveling uniformity is improved when the connecting traces 3 are prepared using the printing process, resulting in more reliable connecting traces 3, reducing the printing difficulty, and evenly distributing the conductive paste. For example, the ratios of the dimension H2 of the groove 61 in the second direction Y to the first spacing H1 can be 0.6, 0.8, or 1.

[0131] In some embodiments, referring to FIG. 13 , a second distance H3 is formed between a side of the bridging structure 6 close to the first selected side surface 1 cc and the first selected side surface 1 cc in the second direction Y.

[0132] It can be understood that the side of the bridging structure 6 close to the first selected side surface 1cc is provided with a second spacing H3 in the second direction Y with the first selected side surface 1cc. On the one hand, a step can be formed between the substrate 1 and the bridging structure 6. Compared with the design in which the boundary of the bridging structure 6 close to the first selected side surface 1cc overlaps or roughly overlaps with the first selected side surface 1cc, while reserving space for the setting of the buffer structure 7, the length of the portion of the connecting trace 3 located between the bridging structure 6 and the first selected side surface 1cc is extended. When the third trace 33 of the connecting trace 3 is prepared by a printing process, the conductive paste can slowly climb, which reduces the printing difficulty and makes the conductive paste more evenly distributed. On the other hand, it can increase the connection firmness between the bridging structure 6 and the substrate 1, and prevent the bridging structure 6 from moving in the subsequent process of the display panel 10 and affecting the position accuracy of the back electrode 4. At the same time, compared with the design in which the boundary of the bridging structure 6 close to the first selected side surface 1cc overlaps or roughly overlaps with the first selected side surface 1cc, it can prevent the bridging structure 6 from warping and other undesirable phenomena near the boundary of the first selected side surface 1cc.

[0133] The above embodiments are all cases where the bridge structure 6 is provided with the groove 61 . The following describes some embodiments where the bridge structure 6 is not provided with the groove 61 .

[0134] 14A and 14B , the buffer structure 7 is disposed on a side of the bridging structure 6 close to the first selected side surface 1cc, the connecting trace 3 crosses the buffer structure 7 and is connected to the back electrode, and the buffer structure 7 is spaced apart from the first selected side surface 1cc.

[0135] It can be understood that by setting the buffer structure 7, on the one hand, the adhesion tightness between the portion of the bridging structure 6 close to the selected side 11cc and the substrate 1 is increased, thereby preventing the back electrode 4 from deviating from the set position due to the displacement of the bridging structure 6, thereby ensuring that the connecting line 3 and the back electrode 4 can be effectively connected, and then ensuring that the driving signal can be transmitted to the light-emitting device through the connecting line 3, ensuring that the display panel 10 can display normally; on the other hand, due to the setting of the buffer structure 7, the buffer structure forms a step, which to a certain extent decomposes the height difference between the second surface 1b and the fourth surface 6b, and the conductive paste can slowly climb through the buffer structure 7, reducing the difficulty of printing, and can relatively easily control the distance between the printing needle P and the buffer structure, and improve the smoothness and uniformity of the conductive paste, so that the width and thickness of the connecting line can be better controlled, avoiding the problem of breakage due to large height difference during the curing process of the conductive paste.

[0136] In some examples, as shown in FIG14A , the thickness of the portion of the side wall of the buffer structure 7 close to the back electrode 4 in the third direction Z is equal to the thickness of the groove 61 in the third direction Z, that is, the thickness of the portion of the side wall of the buffer structure 7 close to the back electrode 4 in the third direction Z is equal to the thickness of the bridging structure 6 in the third direction Z. In the process of printing the second part 332 of the connecting trace 3, due to the setting of the buffer structure 7, the side of the buffer structure 7 away from the second surface 1b is an arc-shaped surface with a certain slope. That is, the height difference between the fourth surface 6b of the bridging structure 6 and the second surface 1b of the substrate 1 becomes an overall gentle slope. The conductive paste can be evenly printed along the side of the buffer structure 7 away from the substrate 1. In the process of continuing to print the third part 333, since there is no height difference between the second part 332 and the third part 333, the printing device can maintain a smooth transition printing at a height, and at the same time, it can avoid the connection trace 3 formed due to the height difference. The phenomenon of breakage is avoided.

[0137] In other examples, as shown in FIG14B , the buffer structure 7 is disposed on the side of the second selected side surface of the bridge structure, and the buffer structure 7 is also disposed on the fourth surface of the bridge structure, wrapping the interface between the second selected side surface and the fourth surface of the bridge structure 6. This allows the conductive paste to pass from the surface of the buffer structure to the fourth surface 6b and connect to the back electrode 4, achieving a smooth transition and reducing the risk of fracture caused by the conductive paste being subjected to greater force at the interface between the second selected side surface and the fourth surface of the bridge structure. Furthermore, the buffer structure 7 is disposed on the fourth surface of the bridge structure 6 and also overlaps multiple back electrodes 4. The surface of the buffer structure 7 is a gently sloping surface. In this way, the formed conductive paste is more easily overlapped with the back electrode 4 along the gently sloping surface of the buffer structure 7 due to its fluidity, further improving preparation efficiency.

[0138] The embodiments of the present disclosure also provide a display device 100. As shown in FIG15 and FIG1 , the display device 100 includes a display panel 10 and a driver circuit board 20 provided in any of the aforementioned embodiments. The driver circuit board 20 is electrically connected to the display panel 10; for example, the driver circuit board 20 is electrically connected to the back electrode 4 of the display panel 10 via the flexible circuit board 8. The electrical signal provided by the driver circuit board 20 is transmitted to the drive circuit layer of the display panel 10 via the flexible circuit board 8, the back electrode 4, the connecting trace 3, and the front electrode 2 to control the light-emitting device to emit light. The driver circuit board 20 is configured to send a drive signal to the display panel 10, thereby driving the display panel 10 to display an image.

[0139] In other embodiments, referring to Figure 16, the driving circuit board 20 is directly connected to the back electrode 4 of the display panel 10, and the electrical signal provided by the driving circuit board 20 is transmitted to the driving circuit layer of the display panel 10 via the back electrode 4, the connecting line 3 and the front electrode 2 to control the light-emitting device to emit light.

[0140] In the display device 100, Mini LED or Micro LED is used as the light-emitting device, which is smaller in size. On a substrate of the same area, the arrangement density of the light-emitting devices 51 per unit area can be higher. In addition, the light-emitting devices 51 can be driven independently or in partitions, thereby improving the uniformity of the display brightness and further improving the display quality of the display device 100.

[0141] The display device 100 can be any device that displays a display, whether in motion (e.g., video), stationary (e.g., still image), text, or an image. More specifically, it is contemplated that the embodiments described may be implemented in or associated with a variety of electronic devices, such as, but not limited to, mobile phones, wireless devices, personal data assistants (PDAs), handheld or portable computers, GPS receivers / navigators, cameras, MP4 video players, camcorders, game consoles, watches, clocks, calculators, television monitors, flat-panel displays, computer monitors, automotive displays (e.g., speedometer displays, etc.), navigation systems, cockpit controls and / or displays, displays of camera views (e.g., displays of rearview cameras in vehicles), electronic photographs, electronic billboards or signs, projectors, architectural structures, packaging, and aesthetic structures (e.g., displays of images of a piece of jewelry), and the like.

[0142] For example, the display device 100 may further include a frame and other electronic components, etc. The display panel 10 may be disposed within the frame, for example.

[0143] The display device 100 has the same structure and beneficial technical effects as the display panel 10 provided in some of the above embodiments, and will not be described in detail here.

[0144] The embodiments of the present disclosure further provide a spliced ​​display device 200 .

[0145] In some embodiments, as shown in FIG17 , a spliced ​​display device 200 includes: a plurality of spliced ​​display panels 10 as described in any of the above embodiments.

[0146] In other embodiments, as shown in FIG. 19 , a spliced ​​display device 200 includes: a plurality of spliced ​​display devices 100 as described in the above embodiments.

[0147] The following description will be made by taking an example where the spliced ​​display device 200 includes a plurality of spliced ​​display devices 100 .

[0148] Exemplarily, as shown in FIG. 17 and FIG. 19 , the display device 100 is, for example, rectangular.

[0149] In some examples, as shown in FIG. 17 , the plurality of display panels 10 in the spliced ​​display device 200 are arranged in an array.

[0150] As shown in FIG1 , in the display panel 10, a plurality of front electrodes 2 are arranged in parallel along a first direction X. Accordingly, a plurality of connecting traces 3 are also arranged in parallel along the first direction X. A direction parallel to the first surface 1 a of the display panel 10 and perpendicular to the first direction X is referred to as a second direction Y. The display device 100 includes multiple side surfaces. Hereinafter, the side surfaces of the display device 100 that are close to the multiple front electrodes 2 are referred to as selected side surfaces of the display device 100 for description.

[0151] Exemplarily, as shown in FIG2 , the display panel 10 includes a display area AA and two binding areas BB located on opposite sides of the display area AA. The display panel 10 includes two groups of front electrodes 2, each group of front electrodes 2 includes a plurality of upper electrodes 2, and the two groups of front electrodes 2 are respectively arranged close to the two binding areas BB.

[0152] Furthermore, as shown in FIG17 , when a plurality of display devices 100 having the display panel 10 as shown in FIG2 are spliced ​​together, for example, the selected side surfaces of two adjacent display devices 100 are arranged along the first direction X. In this way, among the plurality of display devices 100 arranged in a row along the first direction X, there is substantially no splicing seam between two adjacent display devices 100 along the first direction X; and among the plurality of display devices 100 arranged in a column along the second direction Y, there is a splicing gap between two adjacent display devices 100. That is, the size of the splicing gap between two adjacent display devices 100 among the plurality of display devices 100 arranged in a row along the first direction X is smaller than the size of the splicing gap between two adjacent display devices 100 among the plurality of display devices 100 arranged in a column along the second direction Y.

[0153] However, the size of the binding area BB in the second direction Y is very small. Therefore, when the spliced ​​display device 200 is actually viewed, the seam between two adjacent display devices 100 is difficult to be seen by the naked eye within the viewing distance, so that the display image of the spliced ​​display device 200 is more complete and can present a better display effect.

[0154] Exemplarily, as shown in FIG18 , the display panel 10 includes a display area AA and a binding area BB located on one side of the display area AA, and a plurality of front electrodes 2 are provided in the binding area BB.

[0155] Furthermore, as shown in FIG19 , when a plurality of display devices 100 including the display panel 10 shown in FIG18 are spliced ​​together, the selected side surfaces of two adjacent display devices 100 are arranged along the first direction X. In this way, among the plurality of display devices 100 arranged in a row along the first direction X, there is substantially no splicing seam between two adjacent display devices 100 along the first direction X; and among the plurality of display devices 100 arranged in a column along the second direction Y, there is a splicing seam between two adjacent display devices 100. That is, the size of the splicing seam between two adjacent display devices 100 among the plurality of display devices 100 arranged in a row along the first direction X is smaller than the size of the splicing seam between two adjacent display devices 100 among the plurality of display devices 100 arranged in a column along the second direction Y.

[0156] However, the size of the binding area BB in the second direction Y is very small. Therefore, when the spliced ​​display device 200 is actually viewed, the seam between two adjacent display devices 100 is difficult to be seen by the naked eye within the viewing distance, so that the display image of the spliced ​​display device 200 is more complete and can present a better display effect.

[0157] The spliced ​​display device 200 has the same structure and beneficial technical effects as the display device 100 provided in some of the above embodiments, which will not be described in detail here.

[0158] In another aspect, a method for manufacturing a display panel 10 is provided. As shown in FIG. 20A to FIG. 20E , the method for manufacturing the display panel 10 includes:

[0159] R1: Provide initial substrate.

[0160] R2: forming a front film layer structure on the front side of the initial substrate.

[0161] Exemplarily, the front film layer structure includes a driving circuit layer.

[0162] R3: forming a plurality of front electrodes 2 arranged in parallel and spaced apart on the front surface of the initial substrate.

[0163] R4: Cut the initial substrate to form multiple substrates 1; as shown in Figure 20A, the substrate 1 includes a first surface 1a and a second surface 1b arranged opposite to each other, and a plurality of first side surfaces 1c connecting the first surface 1a and the second surface 1b; the plurality of first side surfaces 1c include at least one selected first side surface 1cc.

[0164] The front electrode 2 and the film structure including the driving circuit layer are all disposed on the front surface of the substrate 1. The front electrode 2 is close to the selected first side surface 1cc.

[0165] R5: Disposing the bridge structure 6 on the second surface 1 b of the substrate 1 .

[0166] Referring to Figure 20D , the bridging structure 6 includes a third surface 6a and a fourth surface 6b disposed opposite each other, and a plurality of second side surfaces 6c connecting the third surface 6a and the fourth surface 6b. The third surface 6a is closer to the substrate 1 than the fourth surface 6b. The plurality of second side surfaces 6c include at least one second selected side surface 6cc. Each second selected side surface 6cc corresponds to a first selected side surface 1cc. The portion of the bridging structure 6 adjacent to the first selected side surface is provided with a plurality of grooves 61, with the openings of the plurality of grooves 61 facing the first selected side surface 1cc. Exemplarily, an etching process is employed to form the plurality of grooves 61 in the bridging structure.

[0167] The process of connecting the bridge structure 6 to the second surface 1 b of the substrate 1 is, for example, high-precision bonding.

[0168] Before R5, referring to FIG. 20B and FIG. 20C , a plurality of back electrodes 4 are formed on the fourth surface 6 b of the bridge structure 6. The plurality of back electrodes 4 are close to the second selected side surface 6 cc, and each of the plurality of grooves 61 is provided corresponding to one back electrode 4. Exemplarily, a wet etching process is used to form the plurality of back electrodes 4.

[0169] R6: Referring to Figure 20E, a plurality of connecting traces 3 are formed that are arranged in parallel and spaced apart; each connecting trace 3 among the plurality of connecting traces 3 includes a first trace 31 located on one side of the first surface 1a, a second trace 32 located on one side of the first selected side surface 1cc, and a third trace 33 located on one side of the second surface 1b; the third trace 33 includes a first portion 331, a second portion 332, and a third portion 333 that are connected in sequence; the second portion 332 is located in the groove 61, the third portion 333 is located on one side of the fourth surface 6b, and is connected to the back electrode 4, and the first portion 331 is located between the second portion 332 and the second trace 32.

[0170] Exemplarily, the process for forming the plurality of connecting traces 3 is a printing process, such as three-dimensional printing.

[0171] In some embodiments, the method for preparing the display panel 10 further includes, before step R6:

[0172] R5 - 1 : Referring to FIG. 11A and FIG. 11B , a buffer structure 7 is formed in the groove 61 of the bridge structure 6 .

[0173] In some other embodiments, when the bridge structure is not provided with the groove 61, before step R6, the following steps are included:

[0174] R5-1: Referring to FIG. 14A and FIG. 14B , a buffer structure 7 is formed on a side surface of the bridge structure 6 close to the selected second side surface 1 cc.

[0175] Exemplarily, the buffer structure 7 provided in FIG14B is flush with the back electrode 4 on the side close to the back electrode 4 . For the specific effect, refer to the description in the above section.

[0176] For example, the buffer structure 7 provided in FIG14B overlaps with the back electrode 4 near the side of the back electrode 4, which enables the printing device to perform uniform transition printing, and at the same time avoids the breakage of the connection lines formed due to height difference.

[0177] The process for forming the buffer structure 7 is, for example, three-dimensional printing.

[0178] The above-mentioned preparation processes, such as the printing process, are only described as examples and are not intended to limit the actual production process.

[0179] The above description is merely a specific embodiment of the present disclosure, but the scope of protection of the present disclosure is not limited thereto. Any changes or substitutions that a person skilled in the art can conceive within the technical scope disclosed in the present disclosure should be included within the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure should be based on the scope of protection of the claims.

Claims

1. A display panel, comprising: A substrate, comprising a first surface and a second surface disposed opposite to each other, and a plurality of first side surfaces connecting the first surface and the second surface, at least one first side surface of the plurality of first side surfaces being a first selected side surface; a bridge structure disposed on the second surface, the bridge structure comprising a third surface and a fourth surface disposed opposite to each other, the third surface being closer to the substrate than the fourth surface; wherein a portion of the bridge structure close to the first selected side surface is provided with a plurality of grooves, and the openings of the plurality of grooves face the first selected side surface; A plurality of back electrodes are arranged in parallel and at intervals on the fourth surface; each of the plurality of grooves is arranged corresponding to a back electrode; A plurality of connecting traces are arranged in parallel and at intervals; each connecting trace comprises a first trace located on one side of the first surface, a second trace located on one side of the first selected side surface, and a third trace located on one side of the second surface; the third trace comprises a first portion, a second portion, and a third portion connected in sequence; the second portion is located in the groove, the third portion is located on one side of the fourth surface and connected to the back electrode, and the first portion is located between the second portion and the second trace.

2. The display panel according to claim 1, wherein: A dimension of the second portion along the first direction is smaller than dimensions of the first portion and the third portion along the first direction.

3. The display panel according to claim 1 or 2, wherein: The second portion includes a first sub-portion and a second sub-portion, the average distance between the second sub-portion and the second surface is greater than the average distance between the first sub-portion and the second surface, the second sub-portion is connected to the third portion, and the first sub-portion is connected to the first portion; The size of the first sub-portion in the second direction is greater than the size of the second sub-portion in the second direction, and the second direction is the extending direction of the third routing line.

4. The display panel according to claim 3, wherein: The thickness of the first sub-portion is greater than or equal to the thickness of the first portion, and the thickness of the first sub-portion is greater than the thickness of the third portion.

5. The display panel according to claim 1, wherein: A thickness of a portion of the first portion proximate to the bridge structure is greater than a thickness of a portion of the first portion proximate to the first selected side surface.

6. The display panel according to any one of claims 1 to 5, wherein: The dimension of the groove in the first direction is smaller than the dimension of the back electrode in the first direction, and the first direction is perpendicular to the extending direction of the third wiring.

7. The display panel according to claim 6, wherein: The ratio of the size of the groove in the first direction to the size of the back electrode in the first direction is in the range of 0.5 to 0.

6.

8. The display panel according to any one of claims 1 to 7, wherein: On a plane parallel to and perpendicular to the second direction Y, the groove has multiple cross-sections, and the cross-section farthest from the first selected side surface among the multiple cross-sections has a size in the first direction that is less than or equal to the size of the cross-section closest to the first selected side surface among the multiple cross-sections in the first direction.

9. The display panel according to claim 8, wherein: The orthographic projection of the groove on the second surface is in the shape of a square, a trapezoid, a semicircle or a semi-ellipse.

10. The display panel according to any one of claims 1 to 9, wherein: A buffer structure is disposed at a side wall of the groove close to the back electrode, the second portion is located in the groove and a part of the second portion is located on the buffer structure.

11. The display panel according to any one of claims 1 to 10, wherein: The groove and the corresponding back electrode have a first distance in the second direction; The ratio of the size of the groove in the second direction to the first spacing is in a range of 0.6-1.

12. The display panel according to any one of claims 1 to 11, wherein: A side of the bridging structure close to the first selected side surface has a second distance from the first selected side surface in the second direction.

13. A display device, comprising: The display panel according to any one of claims 1 to 12; A driving circuit board, the driving circuit board is electrically connected to the display panel; The driving circuit board is configured to drive the display panel to display an image.

14. A spliced ​​display device, comprising a plurality of spliced ​​display devices according to claim 13; or a plurality of spliced ​​display panels according to any one of claims 1 to 12.

Images