Display panel, display device and splicing display device

Abstract

A display panel comprises a substrate, a bridging structure, a plurality of back electrodes and a plurality of connecting leads. The substrate comprises a first surface, a second surface and at least one selected first side surface, wherein the first surface and the second surface are oppositely arranged. The bridge structure includes a third surface and a fourth surface, and at least one selected second side surface. The plurality of back electrodes are arranged on the fourth surface in parallel at intervals. The third part of each connecting lead is electrically connected with one back electrode; the third surface and the fourth surface have a first interval. The first common edge is a selected intersecting line of the second side surface and the fourth surface, the second common edge is a selected intersecting line of the second side surface and the third surface, a second interval is formed between the orthographic projection of the first common edge on the third surface and the orthographic projection of the second common edge on the third surface, and the ratio of the first interval to the second interval is 0.27-1.73. The distance between the second common edge and the first selected side surface is a third interval, and the value range of the third interval is 0.5 mm-2. 0mm. The display panel is used for displaying images.

Description

Display panel, display device, spliced ​​display device Technical Field

[0001] 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

[0002] Compared with traditional LEDs, Micro LED (Micro Light Emitting Diode) and Mini LED (Mini Light Emitting Diode Display) have smaller particles and smaller volume. They are widely used in display devices to form Micro LED / Mini LED display devices with higher display effects.

[0003] Summary of the Invention

[0004] On the one hand, a display panel is provided, comprising: a substrate, a bridging structure, a plurality of back electrodes, and a plurality of connecting leads. The substrate comprises a first surface and a second surface disposed opposite each other, and a plurality of first side surfaces connecting the first and second surfaces; the plurality of first side surfaces include at least one selected first side surface. The bridging structure is disposed on the second surface; the bridging structure comprises a third surface and a fourth surface disposed opposite each other, and a plurality of second side surfaces connecting the third and fourth surfaces; the third surface is closer to the substrate than the fourth surface; the plurality of second side surfaces include at least one selected second side surface; each selected second side surface corresponds to a selected first side surface. A plurality of back electrodes are disposed on the fourth surface in parallel and spaced apart. A plurality of connecting leads are arranged in parallel and spaced apart; each connecting lead comprises a first portion located on one side of the first surface, a second portion located on one side of the selected first side surface, and a third portion located on one side of the second surface; the third portion of each connecting lead is electrically connected to a back electrode; the third portion of the connecting lead comprises a portion located on the second surface, a portion located on the selected second side surface, and a portion located on one side of the fourth surface; the third surface and the fourth surface are spaced apart by a first distance. The first common edge is the intersection of the selected second side surface and the fourth surface, the second common edge is the intersection of the selected second side surface and the third surface, the orthographic projection of the first common edge on the third surface and the orthographic projection of the second common edge on the third surface have a second interval, and the ratio of the first interval to the second interval is 0.27 to 1.73. The distance between the second common edge and the first selected side surface is the third interval, and the value range of the third interval is 0.5 mm to 2.0 mm.

[0005] In some embodiments, the portion of the connecting lead located in the area corresponding to the fourth surface has a first thickness, the portion of the connecting lead located in the area corresponding to the second surface has a second thickness, and the connecting lead has a third thickness at a position corresponding to the selected second side surface; wherein the first thickness is greater than or equal to the second thickness, and the difference between the first thickness and the second thickness is 0 to 1 μm; the third thickness is greater than the first thickness or the second thickness, and the difference between the third thickness and the first thickness or the second thickness is 1 μm to 3 μm.

[0006] In some embodiments, a cross section of the second side surface perpendicular to the first common edge or the second common edge is selected to be a straight line segment, a curved line segment, or a broken line segment, and the curved line segment bends away from the second surface.

[0007] In some embodiments, the second side surface is selected as a plane, and the angle between the second side surface and the third surface is selected to be in the range of 10° to 80°.

[0008] In some embodiments, the selected second side surface includes a plurality of sub-surfaces connected in sequence; of two adjacent sub-surfaces, the sub-surface farther from the selected first side surface is farther from the second surface relative to the other sub-surface.

[0009] In some embodiments, the plurality of sub-surfaces are planar, and the selected second side surface is stepped. The selected second side surface includes at least two first sub-surfaces and at least one second sub-surface alternately arranged, and the sub-surface closest to the fourth surface and the sub-surface closest to the second surface among the plurality of sub-surfaces are both first sub-surfaces. At least two first sub-surfaces are parallel to the selected first side surface; and / or the second sub-surface is parallel to the second surface.

[0010] In some embodiments, the dimensions of the orthographic projections of the at least two first sub-surfaces on the first reference plane in the first direction are all the first dimensions; the first reference plane is parallel to the selected first side surface; the first direction is the thickness direction of the substrate; and / or, the dimensions of the orthographic projections of the at least one second sub-surface on the second reference plane in the third direction are all the second dimensions; the second reference plane is parallel to the second surface; and the third direction is perpendicular to the selected first side surface.

[0011] In some embodiments, the bridging structure includes a circuit board, the circuit board includes a fifth surface and a sixth surface arranged opposite to each other, and a plurality of third side surfaces connecting the fifth surface and the sixth surface, the plurality of third side surfaces including at least one selected third side surface; the selected third side surface serves as the selected second side surface; and a plurality of back electrodes are arranged in parallel and spaced apart on the sixth surface.

[0012] In some embodiments, a circuit board includes an adhesive layer and a carrier body stacked together, with the adhesive layer closer to the substrate than the carrier body. A selected third side surface of the circuit board is stepped, and a distance between an end of the carrier body proximate to the selected first side surface and the selected first side surface is smaller than a distance between an end of the adhesive layer proximate to the selected first side surface and the selected first side surface.

[0013] In some embodiments, the ratio of the thickness of the adhesive layer to the thickness of the carrier body is in a range of 1.4 to 1.6.

[0014] In some embodiments, the bridging structure includes: a circuit board and a buffer structure. The circuit board includes a fifth surface and a sixth surface disposed opposite each other, and a plurality of third side surfaces connecting the fifth and sixth surfaces. The plurality of back electrodes are arranged in parallel and spaced relation on the sixth surface. The buffer structure is located on a side of the circuit board proximal to a selected first side surface; an outer surface of the buffer structure serves as at least a portion of a selected second side surface, and is the surface of the buffer structure distal from the circuit board and the second surface.

[0015] In some embodiments, the buffer structure includes a plurality of first sub-buffer structures, and at least a portion of each connecting lead is correspondingly disposed on one of the plurality of first sub-buffer structures.

[0016] In some embodiments, the multiple connecting leads include multiple groups of connecting leads, each group of connecting leads includes at least two connecting leads; the buffer structure includes multiple second sub-buffer structures, and at least a portion of each group of connecting leads is correspondingly arranged on a second sub-buffer structure among the multiple second sub-buffer structures.

[0017] In some embodiments, the buffer structure extends along a second direction, which is the extension direction of the boundary line between the first selected side surface and the second surface, and the length of the buffer structure is greater than the distance between the outer edges of the two outermost connecting leads in the orthographic projection of the multiple connecting leads on the second surface, and the outer edges of the two connecting leads are the sides of the two connecting leads that are away from each other.

[0018] In some embodiments, the cross-section of the surface of the buffer structure away from the circuit board and the second surface that is perpendicular to the first common edge or the second common edge is a straight line segment, a curve segment, or a broken line segment, and the curve segment bends away from the second surface; or, the surface of the buffer structure away from the circuit board and the second surface includes multiple sub-surfaces connected in sequence.

[0019] In some embodiments, the buffer structure further wraps the interface between the selected second side surface and the fourth surface.

[0020] In some embodiments, the material of the buffer structure includes an organic material.

[0021] In some embodiments, the dimension of the end portion of the connecting lead located on the second surface close to the bridging structure in the second direction is larger than the dimension of the other portions of the connecting lead in the second direction; the second direction is the extension direction of the boundary line between the first selected side surface and the second surface.

[0022] In some embodiments, each back electrode includes: a first straight portion, a slanted portion, and a second straight portion. The first straight portion extends in a direction perpendicular to the second direction; the second direction is the extension direction of the boundary line between the first selected side surface and the second surface. The slanted portion is connected to the first straight portion, and the extension direction of the first straight portion intersects with the extension direction of the slanted portion. The second straight portion is connected to the slanted portion and extends in a direction perpendicular to the second direction; the second straight portion is away from the selected first side surface relative to the first straight portion. The third portion of the connecting lead is electrically connected to the first straight portion, and the second straight portion is used to connect to the flexible circuit board. The first straight portions of the plurality of back electrodes are arranged along the second direction, the second straight portions of the plurality of back electrodes are arranged along the second direction, and the size of the plurality of second straight portions along the second direction is smaller than the size of the plurality of first straight portions along the second direction.

[0023] In another aspect, a display device is provided. The display device includes a display panel according to any of the above embodiments and a driver circuit board. The driver circuit board is electrically connected to the display panel and configured to drive the display panel to display an image.

[0024] In another aspect, a spliced ​​display device is provided, comprising a plurality of display devices according to any one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] 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.

[0026] FIG1 is a structural diagram of a display panel according to some embodiments;

[0027] FIG2 is a structural diagram of a display panel according to yet other embodiments;

[0028] FIG3 is a flow chart of a process for preparing a display panel according to some embodiments;

[0029] FIG4 is a structural diagram of a display panel according to yet other embodiments;

[0030] FIG5 is a structural diagram of a display panel according to yet other embodiments;

[0031] FIG6 is a partial enlarged view of point J in FIG4 ;

[0032] FIG7A is a structural diagram of a bridging structure according to some embodiments;

[0033] FIG7B is a structural diagram of a bridging structure according to yet other embodiments;

[0034] FIG7C is a structural diagram of a bridging structure according to yet other embodiments;

[0035] FIG7D is a structural diagram of a bridging structure according to yet other embodiments;

[0036] FIG7E is a structural diagram of a bridging structure according to yet other embodiments;

[0037] FIG7F is a structural diagram of a bridging structure according to yet other embodiments;

[0038] FIG8 is a structural diagram of a bridging structure according to yet other embodiments;

[0039] FIG9 is a structural diagram of a display panel according to yet other embodiments;

[0040] FIG10 is a structural diagram of a bridging structure according to yet other embodiments;

[0041] FIG11 is a structural diagram of a bridging structure according to yet other embodiments;

[0042] FIG12 is a structural diagram of a bridging structure according to yet other embodiments;

[0043] FIG13A is a structural diagram of a bridging structure according to some further embodiments;

[0044] FIG13B is a structural diagram of a bridging structure according to some further embodiments;

[0045] FIG13C is a structural diagram of a bridging structure according to some further embodiments;

[0046] FIG13D is a structural diagram of a bridging structure according to some further embodiments;

[0047] FIG14 is a structural diagram of a display panel according to yet other embodiments;

[0048] FIG15 is a structural diagram of a display panel according to yet other embodiments;

[0049] FIG16 is a structural diagram of a display panel according to yet other embodiments;

[0050] FIG17A is a structural diagram of a bridging structure according to yet other embodiments;

[0051] FIG17B is a structural diagram of a bridging structure according to yet other embodiments;

[0052] FIG17C is a structural diagram of a bridging structure according to yet other embodiments;

[0053] FIG18 is a structural diagram of a display panel according to yet other embodiments;

[0054] FIG19 is a structural diagram of a bridging structure according to yet other embodiments;

[0055] FIG20 is a structural diagram of a display panel according to yet other embodiments;

[0056] FIG21 is a structural diagram of a bridging structure according to still other embodiments;

[0057] FIG22A is a structural diagram of a display device according to some embodiments;

[0058] FIG22B is a structural diagram of a display device according to yet other embodiments;

[0059] FIG23 is a structural diagram of a display panel according to yet other embodiments;

[0060] FIG24 is a structural diagram of a spliced ​​display device according to some embodiments;

[0061] FIG25 is a structural diagram of a display panel according to yet other embodiments;

[0062] FIG26 is a structural diagram of a spliced ​​display device according to further embodiments;

[0063] FIG. 27 is a flow chart of a process for manufacturing a display panel according to yet other embodiments. DETAILED DESCRIPTION

[0064] 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.

[0065] 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.

[0066] 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.

[0067] When describing some embodiments, the expressions "coupled" and "connected" and their derivatives may be used. For example, when describing some embodiments, the term "connected" may be used to indicate that two or more components are in direct physical or electrical contact with each other. For another example, when describing some embodiments, the term "coupled" may be used to indicate that two or more components are in direct physical or electrical contact. However, 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.

[0068] “A and / or B” includes the following three combinations: A only, B only, and a combination of A and B.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] Exemplary embodiments are described herein with reference to cross-sectional and / or plan views that are idealized exemplary drawings. In the drawings, the thicknesses of layers and 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.

[0073] It should be noted that, in the drawings of this disclosure, references such as 11-1 indicate that component 11 belongs to component 1, and references such as 1b-1 indicate that second surface 1b belongs to substrate 1. The above description applies to other similar reference numerals in the drawings. References such as 1 / 2 in the drawings of this disclosure indicate that both plane 1 and plane 2 can refer to this plane. For example, references such as 81cc / 8cc in the drawings indicate that both selected third side surface 81cc and selected second side surface 8cc can be represented by this plane. The above description applies to other similar reference numerals in the drawings.

[0074] 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.

[0075] 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.

[0076] As shown in Figures 1, 2, 4, and 5, in some embodiments, the display panel 10 includes a substrate 1, a plurality of front electrodes 2, a plurality of connecting leads 3, and a plurality of back electrodes 4. The substrate 1 includes a first surface 1a and a second surface 1b disposed opposite 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 selected first side surface 1cc. A plurality of connecting leads 3 are provided corresponding to each selected first side surface 1cc, and the plurality of connecting leads 3 are arranged in parallel and spaced apart. Each connecting lead 3 extends from the first surface, through the selected first side surface 1cc, to the second surface. In other words, each connecting lead 3 includes a first portion 31 located on one side of the first surface 1a, a second portion 32 located on one side of the selected first side surface 1cc, and a third portion 33 located on one side of the second surface 1b.

[0077] Exemplarily, as shown in FIG1 , one side of the first surface 1a of the substrate 1 is the front side 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 1. 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. 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 Display).

[0078] As shown in Figures 1 and 5, 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 22 can be arranged in the binding area BB and arranged in parallel and spaced apart along the second direction Y, where the second direction Y is a direction parallel to the boundary line between the selected first side surface 1cc and the first surface 1a. The plurality of front electrodes 2 are electrically connected to at least a portion of the driving circuit layer (not shown in the figure). The first portions 31 of the plurality of connecting leads 3 are located on the first surface 1a side 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 portions 31 of the plurality of connecting leads 3 is, for example, a direction perpendicular to the selected first side surface 1cc of the substrate 1, i.e., the third direction Z shown in Figure 1.

[0079] For example, as shown in Figures 1 and 5 , the second surface 1b of the substrate 1 is located on the back side of the display panel 10, and the third portions 33 of the plurality of connecting leads 3 are located on the second surface 1b of the substrate 1. That is, the third portions 33 of the connecting leads 3 are the portions of the connecting leads 3 located on the back side of the display panel 10. The third portions 33 of the plurality of connecting leads 3 extend in, for example, the third direction Z. A plurality of back electrodes 4 are disposed on the second surface 1b of the substrate 1 and are arranged in parallel and spaced relation along the second direction Y. The plurality of back electrodes 4 can serve as binding electrodes for connecting to the flexible circuit board 9, and the third portions 33 of the plurality of connecting leads 3 are electrically connected to the plurality of back electrodes 4 in a one-to-one correspondence.

[0080] In some examples, as shown in FIG1 , the display panel 10 further includes a protective layer 6 and a light-blocking layer 7. The protective layer 6 covers the side of the connecting lead 3 and is configured to provide all-round protection for the connecting lead 3, preventing the connecting lead 3 from contacting with air and / or water vapor and causing water-oxygen corrosion, thereby affecting the conductivity of the connecting lead 3. The light-blocking layer 7 covers the side of the protective layer 6 away from the connecting lead 3 and the side of the first surface 1a of the substrate 1. On the one hand, it is configured to prevent external light from entering the display area AA and affecting the display effect. On the other hand, it can prevent light emitted by the light-emitting device layer 5 from leaking at the joints of the spliced ​​display device.

[0081] The method for manufacturing the display panel 10 includes forming a plurality of front electrodes 2 and a drive circuit layer on a first surface 1a of a substrate 1; and forming a plurality of back electrodes 4 on a second surface 1b of the substrate 1. The front electrodes 2 and drive circuit layer may be formed by, for example, etching. The back electrodes 4 may be formed by, for example, laser etching.

[0082] 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.

[0083] Therefore, in order to reduce the manufacturing cost of the display panel 10 while avoiding the impact of the back surface processing of the substrate 1 on the front surface film layers and devices, in some embodiments, as shown in Figures 1 and 4, the display panel 10 also includes a bridging structure 8 disposed on the second surface 1b of the substrate 1; the bridging structure 8 includes a third surface 8a and a fourth surface 8b disposed opposite each other, and a plurality of second side surfaces 8c connecting the third surface 8a and the fourth surface 8b; the third surface 8a is closer to the substrate 1 than the fourth surface 8b; the plurality of second side surfaces 8c include at least one selected second side surface 8cc; each selected second side surface 8cc corresponds to a selected first side surface 1cc. A plurality of back electrodes 4 are disposed in parallel and spaced apart on the fourth surface 8b.

[0084] Exemplarily, the thickness of the bridge structure 8 along the first direction X is 20 μm to 200 μm, and the first direction X is the thickness direction of the substrate 1 .

[0085] By providing a bridging structure 8 on the second surface 1b of the substrate 1, the bridging structure 8 can serve as a carrier of multiple back electrodes 4. In the case where the display panel 10 includes a bridging structure 8, 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 8b of the bridging structure 8, and then the bridging structure 8 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 8a of the bridging structure 8, and at the same time, the front electrode 2 and the back electrode 4 are facing each other in the first direction X. The above-mentioned process of connecting the bridging structure 8 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.

[0086] It should be noted that each of the above-mentioned selected second side surfaces 8cc corresponds to one selected first side surface 1cc, which means that the number of selected second side surfaces 8cc and selected first side surfaces 1cc corresponds, and the selected second side surface 8cc is close to the corresponding selected first side surface 1cc, and the two are arranged along the first direction X.

[0087] It can be understood that, as shown in Figures 1 and 4, when the display panel 10 includes the bridge structure 8, the third portion 33 of the connecting lead 3 includes a portion 331 located on the second surface 1b, a portion 332 located on the selected second side surface 8cc, and a portion 333 located on the side of the fourth surface 8b. The connecting lead 3 extends from the first surface, through the selected first side surface 1cc, to the edge of the second surface, and then through the second side surface 8cc to the fourth surface 8b. In this case, the portions 333 of the third portions 33 of the multiple connecting leads 3 located on the side of the fourth surface 8b are electrically connected to the multiple back electrodes 4 in a one-to-one correspondence.

[0088] The preparation process for the aforementioned multiple connecting leads 3 is, for example, as follows: forming a connecting metal layer entirely on at least one selected first side surface 1cc of the substrate 1, for example, by a three-dimensional sputtering coating process. The formed connecting metal layer covers the first surface 1a of the substrate 1, the selected first side surface 1cc of the substrate 1, and one side of the second surface 1b of the substrate 1. The connecting metal layer located on the second surface 1b of the substrate 1 covers the second surface 1b, the selected second side surface 8cc, and the fourth surface 8b. Subsequently, the connecting metal layer is patterned by laser etching to form multiple independent connecting leads 3. Correspondingly, the connecting metal layers located on the first surface 1a of the substrate 1, the selected first side surface 1cc of the substrate 1, and one side of the second surface 1b of the substrate 1 respectively form the first portion 31, second portion 32, and third portion 33 of the connecting lead 3.

[0089] The light-emitting devices in the above-mentioned display panel 10 are, for example, Micro LEDs or Mini LEDs. Compared with traditional LEDs, the light-emitting device particles are smaller, that is, smaller in size. Therefore, when the display area AA of the display panel 10 has a certain area, more and denser light-emitting devices are installed on the display panel 10, making the connecting leads 3 of the display panel 10 denser, which places higher requirements on the precision and speed of the preparation process of the connecting leads 3. The above-mentioned preparation process of forming a connecting metal layer and patterning by laser etching has low precision and slow preparation speed, which is not conducive to the preparation of the connecting leads 3 of Micro LED and Mini LED display panels 10.

[0090] In order to achieve high-precision and rapid preparation of the connecting leads 3 of the Micro LED and Mini LED display panels 10, in some embodiments, the connecting leads 3 are prepared using a printing process. In this case, as shown in FIG3 , the preparation process of the display panel 10 includes the following steps:

[0091] S1: forming a plurality of front electrodes 2 on the front surface of the initial substrate. In this step, other structures in the driving circuit layer are also formed.

[0092] S2: cutting the initial substrate to form a plurality of substrates 1, wherein a plurality of front electrodes 2 are provided on the front surface of each substrate 1.

[0093] S3: attaching the bridge structure 8 to the back surface of the substrate 1 , with a plurality of back electrodes 4 provided on the fourth surface of the bridge structure 8 , and the back electrodes 4 and the front electrodes 2 facing each other in the first direction X.

[0094] S4: Using a printing process, a conductive paste for connecting leads is formed on the front surface, the selected first side surface, the back surface, the selected second side surface and the fourth surface of the bridging structure of the substrate. The above printing process is, for example, screen printing, pad printing, transfer printing and 3D printing.

[0095] S5: curing the conductive paste to form a plurality of connecting leads 3 .

[0096] S6: forming an initial protective layer on the surfaces of the plurality of connecting leads 3 away from the substrate.

[0097] S7: Curing the initial protective layer to form a protective layer 6.

[0098] S8: Transferring the plurality of light-emitting devices to the front side of the substrate, soldering the light-emitting devices to the solder pads in the driving circuit layer, and completing the die bonding.

[0099] S9: Encapsulating a plurality of light-emitting devices.

[0100] In the preparation process of the above-mentioned display panel 10, on the one hand, when the selected second side surface 8cc of the bridging structure 8 is a plane perpendicular to the third surface 8a, in step S5, since the bridge structure 8 and the second surface 1b of the substrate 1 are stepped, the step difference from the second surface 1b directly to the fourth surface 8b is large, making it difficult for the conductive paste to climb upright on the selected second side surface 8cc, increasing the difficulty of printing while affecting the uniformity of the conductive paste leveling distribution, causing the formed connecting lead 3 to easily break at the junction K between the selected second side surface 8cc and the fourth surface 8b (see the cracks in the connecting line in Figure 2), causing the product circuit to be broken and unable to display. On the other hand, since the conductive paste for the connecting lead is formed by printing, it needs to undergo two curing processes, namely the curing of the conductive paste for the connecting lead and the curing of the initial protective layer, and the curing process is mostly carried out under high temperature conditions, so that the material of the connecting lead 3 needs to undergo two high-temperature processes, which is prone to deformation. At the same time, under the stress at the junction K, the possibility of the connecting lead 3 breaking is further increased.

[0101] Based on this, as shown in Figures 4 and 5, some embodiments of the present disclosure provide a display panel 10, wherein the third surface 8a and the fourth surface 8b of the bridging structure 8 have a first spacing L1. The first common edge H is the intersection of the selected second side surface 8cc and the fourth surface 8b, and the second common edge N is the intersection of the selected second side surface 8cc and the third surface 8a. The orthographic projection of the first common edge H on the third surface 8a and the orthographic projection of the second common edge N on the third surface 8a have a second spacing L2, and the ratio of the first spacing L1 to the second spacing L2 is between 0.27 and 1.73. The distance between the second common edge N and the first selected side surface is a third spacing L3, and the value range of the third spacing L3 is between 0.5 mm and 2.0 mm.

[0102] It can be understood that the third surface 8a and the fourth plane of the bridge structure 8 have a first spacing L1. The first spacing L1 is the dimension of the bridge structure 8 along the first direction X, or in other words, the thickness of the bridge structure 8. When the orthographic projection of the first common side H on the third surface 8a and the orthographic projection of the second common side N on the third surface 8a have a second spacing L2, the second spacing L2 is the dimension of the orthographic projection of the selected second side surface 8cc on the third surface 8a along the third direction Z. In other words, the selected second side surface 8cc is not perpendicular to the third surface 8a and is sloped. When the ratio of the first spacing L1 to the second spacing L2 is between 0.27 and 1.73, the angle between the plane containing the first common side H and the second common side N and the plane containing the third surface 8a ranges from 15° to 60°. This configuration limits the inclination of the selected second side surface 8cc, so that the slope angle at the selected second side surface 8cc is between 15° and 60°. In this way, when forming the connecting leads 3 through the printing process, the conductive paste can slowly slope up on the selected second side surface 8cc, reducing the printing difficulty while improving the uniformity of the conductive paste flow. This makes the subsequently formed connecting leads 3 more reliable and avoids the problem of the connecting leads 3 breaking at the interface K between the selected second side surface 8cc and the fourth surface 8b. Furthermore, because the selected second side surface 8cc is sloped, the connecting leads 3 formed on the selected second side surface 8cc are substantially conformal to the selected second side surface 8cc, i.e., the surface of the connecting leads 3 is also sloped. This makes the connecting leads 3 less likely to deform and, therefore, less likely to break, during the high-temperature curing process of the initial connecting leads and the initial protective layer.

[0103] For example, the ratio of the first interval L1 to the second interval L2 may be 0.27, 0.50, 1, 1.50, or 1.73.

[0104] It can be understood that when the distance between the second common edge N and the first selected side surface is the third interval L3, the third interval L3 is the distance between the edge of the selected second side surface 8cc close to the selected first side surface 1cc and the selected first side surface 1cc. By setting the value range of the third interval L3 to 0.5mm~2.0mm, in the third direction Z, a certain gap is left between the selected second side surface 8cc and the selected first side surface 1cc, so that the selected second side surface 8cc and the selected first side surface 1cc can avoid direct connection, but are connected through a part of the second surface 1b. In this way, when the connecting lead 3 is prepared by the printing process, a part of the third part of the connecting lead is located on the second surface, and the other part is located on the bridging structure, which increases the stability of the connection between the connecting lead and the substrate. At the same time, the connecting lead extends from the second surface through the selected second side surface to the fourth surface, which can avoid the conductive paste from continuously climbing on the selected first side surface 1cc and the selected second side surface 8cc. The conductive paste can slowly climb on the selected second side surface 8cc and the selected first side surface 1cc, reducing the difficulty of printing while the conductive paste is evenly distributed, making the subsequently formed connecting lead 3 more reliable and reducing the risk of the connecting lead 3 breaking. Moreover, since the connecting lead 3 formed on the selected second side surface 8cc is basically conformal to the selected second side surface 8cc, that is, the surface of the connecting lead 3 is also sloped, the force on the connecting lead 3 is more uniform, and it is not easy to deform during the initial high-temperature curing of the connecting lead and the high-temperature curing of the initial protective layer.

[0105] Exemplarily, the third interval L3 may be 0.5 mm, 1.0 mm, 1.5 mm, 1.8 mm, or 2.0 mm.

[0106] It should be noted that the third surface 8a and the fourth surface 8b may be parallel or non-parallel. When the third surface 8a and the fourth surface 8b are non-parallel, the first interval L1 is the average interval between the third surface 8a and the fourth surface 8b. The orthographic projection of the first common side H on the third surface 8a and the orthographic projection of the second common side N on the third surface 8a may be parallel or non-parallel. When the orthographic projection of the first common side H on the third surface 8a and the orthographic projection of the second common side N on the third surface 8a are non-parallel, the second interval L2 is the average interval between the orthographic projection of the first common side H on the third surface 8a and the orthographic projection of the second common side N on the third surface 8a. The second common side N may be parallel or non-parallel to the first selected side surface. When the second common side N is non-parallel to the first selected side surface, the third interval L3 is the average interval between the second common side N and the first selected side surface.

[0107] In some implementations, as shown in FIG1 and FIG2 , a dimension D7 of an end portion C of the connecting lead 3 located on the second surface 1 b and close to the bridge structure 8 in the second direction Y is greater than a dimension D8 of the remaining portion of the connecting lead 3 in the second direction Y. This is because the end portion C of the connecting lead 3 located on the second surface 1 b and close to the bridge structure 8 corresponds to the position before the conductive paste climbs along the selected second side surface 8 cc. It can be understood that, compared with the state when the conductive paste is printed on a plane (for example, the second plane), especially when the selected second side surface 8cc is flat, when the conductive paste is printed on the step G of the selected second side surface 8cc, climbing is more difficult and the moving speed will be slowed down, which causes a certain accumulation of the conductive paste at the position before climbing. The accumulation position corresponds to the end C of the part of the connecting lead 3 located on the second surface 1b close to the bridging structure 8, so that the dimension D7 of the end C of the part of the connecting lead 3 located on the second surface 1b close to the bridging structure 8 in the second direction Y is larger than the dimension D8 of the other parts of the connecting lead 3 in the second direction Y, resulting in low dimensional uniformity of the third part 33 of the connecting lead 3 in the direction perpendicular to its extension direction. At the same time, the thickness uniformity of the third part 33 of the connecting lead 3 is also low.

[0108] In some embodiments, as shown in Figure 6, the portion of the connecting lead 3 located in the area corresponding to the fourth surface 8b has a first thickness d1, the portion of the connecting lead 3 in the area corresponding to the second surface 1b has a second thickness d2, and the connecting lead 3 has a third thickness d3 at the position corresponding to the selected second side surface 8cc; wherein the first thickness d1 is greater than or equal to the second thickness d2, and the difference between the first thickness d1 and the second thickness d2 is 0 to 1 μm; the third thickness d3 is greater than the first thickness d1 or the second thickness d2, and the difference between the third thickness d3 and the first thickness d1 or the second thickness d2 is 1 μm to 3 μm.

[0109] When the difference between the first thickness d1 and the second thickness d2 is between 0 and 1 μm, the difference between the thickness of the portion 331 of the third part 33 of the connecting lead 3 located on the second surface 1b and the portion 333 located on the side of the fourth surface 8b is less than or equal to 1 μm, so that the thickness difference between the two portions is controlled within 1 μm. Correspondingly, the portion 331 of the third part 33 of the connecting lead 3 located on the second surface 1b is formed before the conductive paste climbs along the selected second side surface 8cc, and the portion 333 of the third part 33 of the connecting lead 3 located on the side of the fourth surface 8b is formed after the conductive paste completes climbing along the selected second side surface 8cc. Since the selected second side surface 8cc is a slope, the climbing difficulty is reduced when printing the conductive paste compared to a flat surface, and the accumulation of conductive paste at the position before climbing is reduced, and the thickness and size of the connecting lead at this position are reduced. Through such an arrangement, the thickness difference of the connecting lead 3 is relatively small at the position corresponding to before the conductive paste climbs along the selected second side surface 8cc and the position corresponding to after the conductive paste completes climbing along the selected second side surface 8cc.

[0110] When the difference between the third thickness d3 and the first thickness d1 or the second thickness d2 is between 1 μm and 3 μm, the difference between the thickness of the portion 331 of the third part 33 of the connecting lead 3 located on the second surface 1b and the portion 332 located on the selected second side surface 8cc, and the difference between the thickness of the portion 333 of the connecting lead 3 located on the side of the fourth surface 8b and the portion 332 located on the selected second side surface 8cc are both less than or equal to 3 μm, so that the thickness difference between any two of the portion 331 of the third part 33 of the connecting lead 3 located on the second surface 1b, the portion 332 located on the selected second side surface 8cc, and the portion 333 located on the side of the fourth surface 8b is controlled within 3 μm. Through such an arrangement, the overall thickness difference of the third portion 33 of the connecting lead 3 is small, so that the thickness uniformity of the third portion 33 of the connecting lead 3 is improved, and the size difference between the end of the connecting lead 3 located on the second surface 1b close to the bridging structure 8 and the other parts of the connecting lead 3 is reduced, thereby reducing the risk of the connecting lead 3 breaking.

[0111] For example, the first thickness d1 may be 2 μm, 2.5 μm, 2.7 μm, or 3 μm.

[0112] For example, the second thickness d2 may be 2 μm, 2.2 μm, 2.5 μm, or 3 μm.

[0113] Exemplarily, the third thickness d3 may be 3 μm, 3.7 μm, 4.0 μm, 4.5 μm, or 5 μm.

[0114] The above-mentioned third thickness d3 is greater than the first thickness d1 or the second thickness d2. This is because when the connecting lead 3 is prepared by printing, it is necessary to print and lift the needle at the position corresponding to the selected second side surface 8cc. The moving speed of the conductive paste is slowed down, causing the conductive paste to accumulate, and the actual measured thickness of the connecting lead 3 is high at the position corresponding to the selected second side surface 8cc.

[0115] For example, the difference between the first thickness d1 and the second thickness d2 may be 0 μm, 0.1 μm, 0.5 μm, or 1 μm.

[0116] For example, the difference between the third thickness d3 and the first thickness d1 may be 1 μm, 1.5 μm, 2.0 μm, 2.5 μm, 2.7 μm, or 3.0 μm, and the difference between the third thickness d3 and the second thickness d2 may be 1 μm, 1.8 μm, 2.0 μm, 2.5 μm, or 3.0 μm.

[0117] It should be noted that the first thickness d1 is the average thickness of each portion of the connecting lead 3 located in the region corresponding to the fourth surface 8b, that is, the average thickness of the portion 333 of the third portion 33 of the connecting lead 3 located on the fourth surface 8b side. Furthermore, the direction of the first thickness d1 is the first direction X, which is perpendicular to the fourth surface 8b. The second thickness d2 is the average thickness of each portion of the connecting lead 3 located in the region corresponding to the second surface 1b, that is, the average thickness of the portion 331 of the third portion 33 of the connecting lead 3 located on the second surface 1b. Furthermore, the direction of the second thickness d2 is the first direction X, which is perpendicular to the second surface 1b. The third thickness d3 is the average thickness of each portion of the connecting lead 3 located in the region corresponding to the selected second side surface 8cc, that is, the average thickness of the portion 332 of the third portion 33 of the connecting lead 3 located on the selected second side surface 8cc. Furthermore, the direction of the third thickness d3 is perpendicular to the selected second side surface 8cc.

[0118] In some embodiments, as shown in FIG. 7A to FIG. 7F , a cross section of the second side surface 8cc perpendicular to the first common edge H or the second common edge N is selected to be a straight line segment, a curved line segment, or a broken line segment, and the curved line segment bends away from the second surface 1b .

[0119] As shown in Figure 7A, when the cross-section of the second side surface 8cc perpendicular to the first common edge H or the second common edge N is selected as a straight line segment, the second side surface 8cc is selected as an inclined plane. Compared with the case where the second side surface 8cc is selected to be perpendicular to the third surface 8a, the uniformity of the leveling of the conductive paste is improved when preparing the connecting lead 3 through the printing process, and the formed connecting lead 3 is more reliable.

[0120] As shown in FIG7B , when the cross-section of the second side surface 8cc perpendicular to the first common edge H or the second common edge N is selected as a curved segment, the second side surface 8cc is selected as an inclined curved surface. Compared to the case where the second side surface 8cc is selected to be perpendicular to the third surface 8a, the conductive paste leveling uniformity is improved during the printing process to form the connecting leads 3, and the resulting connecting leads 3 are more reliable. Furthermore, the curved segment bends away from the second surface 1b, that is, the second side surface is selected as an outwardly convex curved surface. By setting the curved segment to bend away from the second surface 1b, the inclined curved surface can be prevented from forming a relatively upright slope near the fourth surface 8b, thereby avoiding the problem of the conductive paste having difficulty climbing the slope when printing the initial connecting leads.

[0121] It should be noted that when a cross section of the second side surface 8cc perpendicular to the first common side H or the second common side N is selected as a curved segment, the number of curved segments can be one or more, and there is no limitation here. In the case where there are multiple curved segments, the multiple curved segments are connected in sequence and are inclined as a whole.

[0122] As shown in Figures 7C to 7F, when the cross-section of the second side surface 8cc perpendicular to the first common edge H or the second common edge N is selected as a broken line segment, the second side surface 8cc is selected to be sawtooth-like as a whole. Compared with the case where the second side surface 8cc is selected to be perpendicular to the third surface 8a, the uniformity of the leveling of the conductive paste is improved when preparing the connecting lead 3 through the printing process, and the formed connecting lead 3 is more reliable.

[0123] In some embodiments, as shown in FIG. 7A , the second side surface 8cc is selected as a plane, and the angle between the second side surface 8cc and the third surface 8a is selected to be in the range of 10° to 80°.

[0124] When the angle α between the second side surface 8cc and the third surface 8a is selected to be in the range of 10° to 80°, the angle β between the second side surface 8cc and the fourth surface 8b is selected to be in the range of 100° to 170°. In this way, when the connecting lead 3 is formed by the printing process, the conductive paste can be kept in a state of slowly climbing on the selected second side surface 8cc.

[0125] By selecting the angle α between the second side surface 8cc and the third surface 8a to be less than or equal to 80°, the angle α between the second side surface 8cc and the third surface 8a is kept small, thereby preventing the formation of a relatively vertical slope. This, in turn, avoids the problem of the conductive paste having difficulty climbing the slope when printing the initial connection leads. By selecting the angle α between the second side surface 8cc and the third surface 8a to be greater than or equal to 10°, the angle α between the second side surface 8cc and the third surface 8a is kept small, thereby facilitating ensuring the third interval L3.

[0126] Exemplarily, the angle α between the second side surface 8cc and the third surface 8a may be selected to be 10°, 20°, 30°, 40°, 45°, 60°, or 80°.

[0127] In some embodiments, as shown in FIG7D , the selected second side surface 8cc includes a plurality of sub-surfaces 8cc1 connected sequentially; of two adjacent sub-surfaces 8cc1 , the sub-surface 8cc1 farther from the selected first side surface 1cc is farther from the second surface 1b relative to the other sub-surface 8cc1 .

[0128] By setting it this way, two adjacent sub-surfaces 8cc1 can be arranged in the direction from the second common edge N to the first common edge H, and the angle between this arrangement direction and the third plane of the bridge structure 8 is less than 90°. In this way, when preparing the connecting lead 3 through the printing process, the conductive paste can slowly climb on the selected second side surface 8cc, which reduces the difficulty of printing while improving the uniformity of the conductive paste leveling, making the subsequently formed connecting lead 3 more reliable, and avoiding the problem of the connecting lead 3 breaking at the junction K between the selected second side surface 8cc and the fourth surface 8b (see the crack in the connecting line in Figure 2). Moreover, since the connecting lead 3 formed on the selected second side surface 8cc is basically conformal to the selected second side surface 8cc, that is, the surface of the connecting lead 3 is also sloped, the connecting lead 3 is not easily deformed during the high-temperature curing of the initial connecting lead and the high-temperature curing of the initial protective layer.

[0129] It should be noted that, when the sub-surface 8cc1 of two adjacent sub-surfaces 8cc1 that is further away from the selected first side surface 1cc is further away from the second surface 1b relative to the other sub-surface 8cc1, this means that the sub-surface 8cc1 of the two adjacent sub-surfaces 8cc1 that is further away from the selected first side surface 1cc and the sub-surface 8cc1 that is further away from the second surface 1b are the same sub-surface 8cc1. The following uses sub-surfaces 8cc1A and 8cc1B of the selected second side surface 8cc as an example for a specific description. As shown in FIG7D , of sub-surfaces 8cc1A and 8cc1B of the selected second side surface 8cc, sub-surface 8cc1A is the sub-surface 8cc1 that is further away from the selected first side surface 1cc, and sub-surface 8cc1A is the sub-surface 8cc1 that is further away from the second surface 1b.

[0130] For example, all of the sub-surfaces 8cc1 are curved surfaces, or all of the sub-surfaces 8cc1 are flat surfaces, or some of the sub-surfaces 8cc1 are curved, while the remaining sub-surfaces 8cc1 are flat surfaces. When some of the sub-surfaces 8cc1 are curved, while the remaining sub-surfaces 8cc1 are flat surfaces, the arrangement of the flat and curved sub-surfaces 8cc1 is not limited.

[0131] In some embodiments, as shown in Figures 7D to 7F , multiple sub-surfaces 8cc1 are planar, and the selected second side surface 8cc is stepped. The selected second side surface 8cc includes at least two first sub-surfaces 8cc1a and at least one second sub-surface 8cc1b arranged alternately. The sub-surfaces 8cc1 closest to the fourth surface 8b and the sub-surface 8cc1 closest to the second surface 1b of the multiple sub-surfaces 8cc1 are both first sub-surfaces 8cc1a. At least two first sub-surfaces 8cc1a are parallel to the selected first side surface 1cc; and / or the second sub-surface 8cc1b is parallel to the second surface 1b.

[0132] Taking the directions shown in Figures 7D to 7F as an example, when multiple sub-surfaces 8cc1 are planes and the selected second side surface 8cc is stepped, the selected second side surface 8cc includes at least two connecting surfaces and at least one stepped surface. The first sub-surface 8cc1a is the connecting surface, and the second sub-surface 8cc1b is the stepped surface. Among the multiple sub-surfaces 8cc1, the sub-surfaces adjacent to the fourth surface 8b or adjacent to the second surface 1b are all first sub-surfaces 8cc1a, as shown in Figures 7D and 7E. When at least two first sub-surfaces 8cc1a are parallel to the selected first side surface 1cc, the connecting surface is perpendicular to the third surface 8a. The second sub-surface 8cc1b is not limited and can be parallel to the second surface 1b or not. As shown in Figures 7D and 7F, when the second sub-surface 8cc1b is parallel to the second surface 1b, the stepped surface is parallel to the third surface 8a. The first sub-surface 8cc1a is not limited and can be parallel to the selected first side surface 1cc or not.

[0133] By configuring the selected second side surface 8cc to be stepped, compared to a case where the selected second side surface 8cc is a plane perpendicular to the third surface 8a, the conductive paste's vertical slope on the selected second side surface 8cc during the printing process is transformed into a stepwise slope. This reduces printing difficulty while improving the uniformity of the conductive paste's leveling, making the subsequently formed connecting leads 3 more reliable and avoiding the problem of connecting leads 3 breaking at the interface K between the selected second side surface 8cc and the fourth surface 8b. Furthermore, because the connecting leads 3 formed on the selected second side surface 8cc are substantially conformal to the selected second side surface 8cc, i.e., the surface of the connecting leads 3 also has a slope, the connecting leads 3 are less likely to deform during the initial high-temperature curing of the connecting leads and the initial high-temperature curing of the protective layer.

[0134] In some embodiments, as shown in Figures 7D to 7F, the dimensions of the orthographic projections of at least two first sub-surfaces 8cc1a on the first reference plane in the first direction X are both the first dimension D1; the first reference plane is parallel to the selected first side surface 1cc; and the first direction X is the thickness direction of the substrate 1.

[0135] With this configuration, the selected second side surface 8cc becomes a plurality of equal-height connection surfaces, and the first interval L1 with a large step difference is decomposed into a plurality of smaller steps in the first direction X. This improves the flow uniformity of the conductive paste on the selected second side surface 8cc when the connecting leads 3 are formed through the printing process, thereby reducing the printing difficulty and improving the uniformity of the conductive paste flow.

[0136] In some embodiments, as shown in Figures 7D to 7F, the orthographic projection of at least one second sub-surface 8cc1b on the second reference plane has a dimension in the third direction Z that is the second dimension D2; the second reference plane is parallel to the second surface 1b; and the third direction Z is perpendicular to the selected first side surface 1cc.

[0137] Thus, the orthographic projections of two adjacent second sub-surfaces 8cc1b of the selected second side surface 8cc on the third surface 8a do not overlap, and their orthographic projections on a plane parallel to the selected first side surface 1cc are arranged at equal intervals. The second interval L2 is divided into multiple portions of equal size in the third direction Z. This improves the uniformity of the conductive paste flow on the selected second side surface 8cc when forming the connecting lead 3 through the printing process.

[0138] In other embodiments, as shown in FIG7D , the orthographic projections of at least two first sub-surfaces 8cc1a on the first reference plane each have a first dimension D1 in the first direction X. Furthermore, the orthographic projection of at least one second sub-surface 8cc1b on the second reference plane each has a second dimension D2 in the third direction Z. Furthermore, the first dimension D1 and the second dimension D2 are equal.

[0139] By this arrangement, the stepped surfaces and connecting surfaces of the selected second side surface 8cc are of equal size, the first interval L1 with a large step difference is broken down into multiple smaller steps in the first direction X, and the second interval L2 is divided into multiple even steps in the third direction Z. This allows the conductive paste to flow evenly on the selected second side surface 8cc when forming the connecting lead 3 through the printing process.

[0140] The following describes the composition of the bridge structure and the specific implementation method of selecting the second side surface to be a sloped surface.

[0141] In some embodiments, as shown in Figure 8, the bridging structure 8 includes a circuit board 81, the circuit board 81 includes a fifth surface 81a and a sixth surface 81b arranged opposite to each other, and a plurality of third side surfaces 81c connecting the fifth surface 81a and the sixth surface 81b, the plurality of third side surfaces 81c include at least one selected third side surface 81cc; the selected third side surface 81cc serves as the selected second side surface 8cc; and a plurality of back electrodes 4 are arranged in parallel and spaced apart on the sixth surface 81b.

[0142] When the bridge structure 8 includes a circuit board 81, the fifth surface 81a of the circuit board 81 is the third surface 8a of the bridge structure 8; the sixth surface 81b of the circuit board 81 is the fourth surface 8b of the bridge structure 8. In this case, the circuit board 81 can serve as a carrier for the plurality of back electrodes 4.

[0143] In some embodiments, as shown in Figures 8 and 9, circuit board 81 includes a stacked adhesive layer 811 and a carrier body 812, with adhesive layer 811 closer to substrate 1 than carrier body 812. As shown in Figure 8, adhesive layer 811 and carrier body 812 are cut so that the surfaces of adhesive layer 811 and carrier body 812 closer to the selected first side surface are inclined surfaces, that is, selected third side surface 81cc of circuit board 81 is inclined surfaces, so that the first common edge H of selected third side surface 81cc of circuit board 81 is farther away from the selected first side surface 81cc than the second common edge N, and a second gap exists between the orthographic projections of the two third side surfaces on the second surface of the substrate.

[0144] As shown in Figure 9, the selected third side surface 81cc of the circuit board 81 is stepped, and the distance D4 between the end of the carrier body 812 close to the selected first side surface 1cc and the selected first side surface 1cc is smaller than the distance D3 between the end of the adhesive layer 811 close to the selected first side surface 1cc and the selected first side surface 1cc.

[0145] The carrier body 812 is the portion of the circuit board 81 that serves as a carrier for the multiple back electrodes 4. The adhesive layer 811 is used to connect the carrier body 812 to the backplane. It is understood that the adhesive layer 811 is closer to the substrate 1 relative to the carrier body 812, thereby fulfilling the adhesive layer 811's function of connecting the carrier body 812 to the backplane. By setting the distance D4 between the end of the carrier body 812 near the selected first side surface 1cc and the selected first side surface 1cc to be smaller than the distance D3 between the end of the adhesive layer 811 near the selected first side surface 1cc and the selected first side surface 1cc, a step is formed on the selected third side surface 81cc of the circuit board 81, satisfying the requirement that the ratio of the first spacing L1 to the second spacing L2 be between 0.27 and 1.73. This allows the conductive paste to gradually climb the slope on the selected third side surface 81cc when preparing the connecting leads 3 through the printing process, reducing the printing difficulty while achieving a more uniform distribution of the conductive paste.

[0146] For example, as shown in FIG9 , when selected third side surface 81cc of circuit board 81 is stepped, first sub-surfaces 8cc1 may be two in number. End surface 811a of adhesive layer 811 proximal to selected first side surface 1cc serves as first sub-surface 8cc1a proximal to substrate 1, and end surface 812a of carrier body 812 proximal to selected first side surface 1cc serves as first sub-surface 8cc1a distal to substrate 1. Adhesive layer 811 proximal to selected first side surface 1cc, carrier body 812 proximal to selected first side surface 1cc, and second sub-surface 8cc1b located therebetween collectively constitute selected second side surface 8cc.

[0147] With this arrangement, the carrier body 812 and the adhesive layer 811 can be cut in batches, and the cutting line of the adhesive layer 811 is closer to the selected first side surface 1cc relative to the cutting line of the carrier body 812, thereby forming a stepped selected third side surface 81cc, which simplifies the method of forming the selected third side surface 81cc of the circuit board 81.

[0148] For example, the carrier body is made of polyimide, which has the characteristics of high precision, high temperature resistance, and low expansion and contraction, so that the carrier body is not easily displaced during subsequent high-temperature processes, such as reflow soldering.

[0149] In some embodiments, as shown in FIG. 9 , the thickness d3 of the adhesive layer 811 is greater than the thickness d4 of the carrier body 812 .

[0150] By such an arrangement, the connection firmness between the carrier body and the substrate 1 can be increased, and the carrier body 812 can be prevented from moving during the subsequent manufacturing process of the display panel 10 and affecting the position accuracy of the back electrode 4 .

[0151] In some embodiments, as shown in FIG. 9 , the ratio of the thickness d3 of the adhesive layer 811 to the thickness d4 of the carrier body 812 is in a range of 1.4 to 1.6.

[0152] It is understood that when the difference between the thickness d3 of the adhesive layer 811 and the thickness d4 of the carrier body 812 is too large, the thickness of the thicker of the adhesive layer 811 and the carrier body 812 will approach the thickness of the circuit board 8. As a result, even if a stepped selected second side surface 8cc is formed, the step difference of the selected second side surface 8cc will still be large, and the conductive paste cannot be applied gradually on the selected second side surface 8cc. By setting the ratio of the thickness d3 of the adhesive layer 811 to the thickness d4 of the carrier body 812 within a range of 1.4 to 1.6, the difference between the thickness d3 of the adhesive layer 811 and the thickness d4 of the carrier body 812 will not be too large, and a stepped selected second side surface 8cc can be formed. Compared to a case where the selected second side surface 8cc is a plane perpendicular to the third surface 8a, the conductive paste leveling uniformity is improved when forming the connecting lead 3 through the printing process, resulting in a more reliable connecting lead 3, reduced printing difficulty, and a uniform distribution of the conductive paste. For example, the ratio of the thickness d3 of the adhesive layer 811 to the thickness d4 of the carrier body 812 may be 1.4, 1.5, or 1.6.

[0153] To enhance the feasibility of high-precision attachment of the circuit board 81 to the second surface 1b of the substrate 1, in some examples, as shown in Figures 10 and 11, before the circuit board 81 is attached to the second surface 1b of the substrate 1, a release film E is provided on the side of the adhesive layer 811 facing away from the carrier body 812; and a reinforcing film F is provided on the side of the carrier body 812 facing away from the adhesive layer 811. The release film E prevents foreign matter from adhering to the adhesive layer 811 before the circuit board 81 is attached, thereby affecting the bonding performance. The reinforcing film F increases the strength of the carrier body 812, preventing curling or bending of the carrier body during the attachment process, which could affect the attachment of the circuit board 81. It should be noted that the release film E needs to be removed before the circuit board 81 is attached, and the reinforcing film F needs to be removed after the circuit board 81 is attached.

[0154] The above embodiment improves the structure of the circuit board 81 itself to form an inclined selected second side surface of the bridge structure. Another implementation method is described below.

[0155] In some embodiments, as shown in Figure 12, bridging structure 8 includes a circuit board 81 and a buffer structure 82. Circuit board 81 includes a fifth surface 81a and a sixth surface 81b disposed opposite each other, and a plurality of third side surfaces 81c connecting fifth and sixth surfaces 81a, 81b. A plurality of back electrodes 4 are arranged in parallel and spaced relation on sixth surface 81b. Buffer structure 82 is located on a side of circuit board 81 proximal to a selected first side surface 1cc. An outer surface 82a of the buffer structure serves as at least a portion of a selected second side surface 8cc and is the surface of the buffer structure 82 distal from circuit board 81 and second surface 1b.

[0156] It should be noted that the above-mentioned buffer structure outer surface 82a is the surface of the buffer structure 82 away from the circuit board 81 and the second surface 1b, which means that as shown in Figure 12, the surface of the buffer structure 82 can be divided into three parts. The first part is the first inner surface 82b of the buffer structure 82 in contact with the circuit board 81, the second part is the second inner surface 82c of the buffer structure 82 in contact with the second surface 1b of the substrate 1, and the third part is the buffer structure outer surface 82a, which is the part indicated by the rectangular dotted line in Figure 12.

[0157] The above-mentioned buffer structure 82 is located on the side of the circuit board 81 close to the selected first side surface 1cc. By setting the buffer structure 82 on the side of the circuit board close to the selected first side surface 1cc, the outer surface 82a of the buffer structure serves as at least a part of the selected second side surface 8cc, so that the intersection edge of the outer surface 82a of the buffer structure and the second inner surface 82c serves as the second common edge N, and the first common edge H is the intersection edge of the sixth surface 81b of the circuit board 81 and the selected third side surface 81cc. Compared with the case without the buffer structure 82, such a setting can make the second common edge N further away from the first common edge H, which is conducive to forming a second interval L2 between the second common edge N and the first common edge H, so that the selected second side surface 8cc is a slope, and the uniformity of the leveling of the conductive paste is improved when preparing the connecting lead 3 through the printing process, and the formed connecting lead 3 is more reliable.

[0158] The outer surface 82a of the buffer structure is selected as at least a portion of the second side surface 8cc. In this way, when the connecting lead 3 is prepared by a printing process, the conductive paste can slowly climb on the outer surface 82a of the buffer structure.

[0159] The bridge structure 8 includes a circuit board 81 and a buffer structure 82. The outer surface 82a of the buffer structure is selected as at least a portion of the second side surface 8cc, and at least four situations are included:

[0160] Case 1: As shown in Figures 12 and 13A, the side surface of circuit board 81 proximal to the selected first side surface 1cc is a plane perpendicular to third surface 8a. Buffer structure 82 is located on the side of circuit board 81 proximal to the selected first side surface 1cc. Furthermore, dimension d7 of buffer structure 82 along first direction X is less than thickness d5 of circuit board 81. In this case, side surface 81c of circuit board 81 proximal to the selected first side surface 1cc and outer surface 82a of the buffer structure together constitute selected second side surface 8cc. The provision of buffer structure 82 softens the slope of the portion of selected second side surface 8cc proximal to second surface 1b of substrate 1.

[0161] In the second scenario, as shown in Figures 12 and 13B , the side surface of circuit board 81 adjacent to selected first side surface 1cc is a plane perpendicular to third surface 8a. Buffer structure 82 is located on the side of circuit board 81 adjacent to selected first side surface 1cc. Furthermore, dimension d5 of buffer structure 82 along first direction X is greater than or equal to thickness d7 of circuit board 81. In this scenario, outer surface 82a of the buffer structure corresponds to selected second side surface 8cc. The provision of buffer structure 82 softens the overall slope of selected second side surface 8cc.

[0162] Case 3: As shown in Figures 12 and 13C , circuit board 81 includes a fifth surface 81a and a sixth surface 81b disposed opposite each other, and multiple third side surfaces 81c connecting fifth and sixth surfaces 81a, 81b. These multiple third side surfaces 81c include at least one selected third side surface 81cc. A cross-section of selected third side surface 81cc perpendicular to first common edge H or second common edge N is a straight line, a curved line, or a broken line segment, with the curved line segment curving away from second surface 1b. Alternatively, selected third side surface 81cc includes multiple sequentially connected sub-surfaces 8cc1. A buffer structure 82 is located on a side of circuit board 81 proximal to the selected first side surface 1cc. Furthermore, a dimension d7 of buffer structure 82 along the first direction X is less than the thickness d5 of circuit board 81. In this case, selected third side surface 81cc and buffer structure outer surface 82a together constitute selected second side surface 8cc, resulting in a gentler overall slope of selected second side surface 8cc. By selecting the third side surface 81cc, the slope of the portion of the second side surface 8cc away from the second surface 1b of the substrate 1 is slowed down, and by providing the buffer structure 82, the slope of the portion of the second side surface 8cc close to the second surface 1b of the substrate 1 is slowed down.

[0163] Case 4: As shown in Figures 12 and 13D, circuit board 81 includes a fifth surface 81a and a sixth surface 81b disposed opposite each other, and multiple third side surfaces 81c connecting fifth and sixth surfaces 81a, 81b. These multiple third side surfaces 81c include at least one selected third side surface 81cc. A cross-section of selected third side surface 81cc perpendicular to first common edge H or second common edge N is a straight line, a curved line, or a broken line segment, with the curved line segment curving away from second surface 1b. Alternatively, selected third side surface 81cc includes multiple sequentially connected sub-surfaces 8cc1. A buffer structure 82 is located on a side of circuit board 81 proximal to the selected first side surface 1cc. Furthermore, a dimension d5 of buffer structure 82 along the first direction X is greater than or equal to the thickness d7 of circuit board 81. In this case, outer surface 82a of the buffer structure corresponds to the selected second side surface 8cc. Thus, the slope of selected second side surface 8cc is softened by the selected third side surface 81cc, and the slope of selected second side surface 8cc is further softened by the provision of buffer structure 82. Among them, the third and fourth cases are implementation methods that combine improvements to the structure of the circuit board itself with the provision of a buffer structure.

[0164] In some embodiments, as shown in FIG. 14 , the buffer structure 82 includes a plurality of first sub-buffer structures 821 , and at least a portion of each connecting lead 3 is correspondingly disposed on one of the plurality of first sub-buffer structures 821 .

[0165] In this case, the number of the multiple first sub-buffer structures 821 matches the number of the multiple connecting leads 3, and the multiple first sub-buffer structures 821 are arranged along the second direction Y, which is equivalent to forming multiple arc-shaped island-shaped buffer blocks on the side surface of the circuit board 81. In this way, when the connecting leads 3 are prepared through the printing process, the conductive paste forming each connecting lead 3 can slowly climb along the outer surface of the corresponding first sub-buffer structure 821. It should be noted that for the description of the outer surface of the first sub-buffer structure 821, please refer to the aforementioned description of the buffer structure outer surface 82a, and will not be repeated here.

[0166] In some embodiments, as shown in Figure 15, the multiple connecting leads 3 include multiple groups of connecting leads 3, each group of connecting leads 3 includes at least two connecting leads 3; the buffer structure 82 includes multiple second sub-buffer structures 822, and at least a portion of each group of connecting leads 3 is correspondingly arranged on a second sub-buffer structure 822 among the multiple second sub-buffer structures 822.

[0167] In this case, the number of the multiple second sub-buffer structures 822 matches the number of the multiple groups of connecting leads 3, and the multiple first sub-buffer structures 821 are arranged along the second direction Y, which is equivalent to forming multiple groups of buffer strips on the side surface of the circuit board 81. In this way, when the connecting leads 3 are prepared through the printing process, the conductive paste forming each group of connecting leads 3 can slowly climb along the outer surface of the corresponding second sub-buffer structure 822. It should be noted that for the description of the outer surface of the second sub-buffer structure 822, please refer to the aforementioned description of the buffer structure outer surface 82a, and will not be repeated here.

[0168] Exemplarily, as shown in FIG. 15 , each group of connecting leads 3 includes three connecting leads 3 .

[0169] In some embodiments, as shown in Figure 16, the buffer structure 82 extends along the second direction Y, the second direction Y is the extension direction of the boundary line between the selected first side surface 1cc and the second surface 1b, and the length D5 of the buffer structure 82 is greater than the distance D6 between the outer sides P of the two outermost connecting leads 3 in the orthographic projection of the multiple connecting leads 3 on the second surface 1b, and the outer sides P of the two connecting leads 3 are the sides of the two connecting leads 3 that are away from each other.

[0170] This arrangement is equivalent to forming a continuous buffer layer on the side surface of circuit board 81, simplifying the manufacturing process of buffer structure 82 while ensuring that a portion of buffer structure 82 is provided on the side of each connecting lead 3 away from the selected first side surface 1cc. This allows each connecting lead 3 to gradually slope along a portion of the outer surface 82a of the buffer structure when the connecting leads 3 are manufactured through the printing process.

[0171] In some embodiments, as shown in Figures 17A to 17C, the cross-section of the surface of the buffer structure 82 away from the circuit board 81 and the second surface 1b that is perpendicular to the first common edge H or the second common edge N is a straight line segment, a curve segment, or a broken line segment, and the curve segment bends toward away from the second surface 1b; or, the surface of the buffer structure 82 away from the circuit board 81 and the second surface 1b includes multiple sub-surfaces 82a1 connected in sequence.

[0172] The surface of the above-mentioned buffer structure 82 away from the circuit board 81 and the second surface 1b is the outer surface 82a of the buffer structure. When the outer surface 82a of the buffer structure is used as at least a part of the selected second side surface 8cc, through the above-mentioned setting, the slope on the outer surface 82a of the buffer structure becomes gentler, that is, the slope of at least a part of the selected second side surface 8cc becomes gentler. When the connecting lead 3 is prepared by the printing process, the conductive paste slowly climbs on the outer surface 82a of the buffer structure.

[0173] In some embodiments, as shown in Figures 18 and 19, the buffer structure 82 extends along a second direction Y, which is the direction extending from the boundary line between the selected first side surface 1cc and the second surface 1b. The length D5 of the buffer structure 82 is greater than the distance D6 between the outer edges P of the two outermost connecting leads 3 in the orthographic projection of the second surface 1b. The outer edges P of the two connecting leads 3 are the sides of the two connecting leads 3 that are away from each other. Furthermore, the buffer structure 82 includes a plurality of third sub-buffer structures 823 arranged along the first direction X and having the same dimensions along the second direction Y. These third sub-buffer structures 823 give the buffer structure's outer surface 82a a stepped shape.

[0174] This arrangement reduces the step difference on the outer surface 82a of the buffer structure. The first interval L1, which has a large step difference, is broken down into multiple smaller steps in the first direction X. Simultaneously, the second interval L2 is divided into multiple segments in the third direction Z. This improves the flow rate of the conductive paste on the selected second side surface 8cc during the printing process for forming the connecting leads 3. Furthermore, the overall strip-shaped structure of the buffer structure 82 simplifies the manufacturing process.

[0175] For example, as shown in Figures 18 and 19 , the plurality of third sub-buffer structures 823 are four, namely, third sub-buffer structure 823a, third sub-buffer structure 823b, third sub-buffer structure 823c, and third sub-buffer structure 823d. As shown in Figure 19 , the thickness d5 of the circuit board 81 in the first direction X is 0.1 mm, and the thicknesses of the plurality of third sub-buffer structures 823 in the first direction X are equal. For example, the thickness d6 of each third sub-buffer structure 823 in the first direction X is 20 μm. This arrangement makes the step differences between adjacent step surfaces of the buffer structure outer surface 82a more consistent. When forming the connecting lead 3 through the printing process, the leveling uniformity of the conductive paste on the selected second side surface 8cc is improved, and the subsequently formed connecting lead 3 is prevented from breaking due to the large step differences.

[0176] In some embodiments, as shown in FIG. 13B , FIG. 13D , and FIG. 17B , a boundary T between a side surface 81 c of the circuit board 81 , which is close to the selected first side surface 1 cc , and the sixth surface 81 b of the circuit board 81 .

[0177] Because the intersection of the side surface 81c of the circuit board 81 near the selected first side surface 1cc and the sixth surface 81b of the circuit board 81 is relatively sharp, the conductive paste is subjected to greater force at this location and is easily deformed during the high-temperature curing of the initial connecting lead and the high-temperature curing of the initial protective layer, increasing the possibility of fracture of the connecting lead 3. Based on this, by providing a buffer structure 82 that wraps the side surface 81c of the circuit board 81 near the selected first side surface 1cc and the intersection T between the sixth surface 81b of the circuit board 81, when the connecting lead 3 is prepared by the printing process, the conductive paste forming the connecting lead 3 can bypass the side surface 81c of the circuit board 81 near the selected first side surface 1cc, reach the sixth surface 81b of the circuit board 81 at the intersection with the sixth surface 81b of the circuit board 81, and connect with the back electrode 4, achieving a smooth transition and reducing the risk of the conductive paste fracturing at the intersection of the side surface 81c of the circuit board 81 near the selected first side surface 1cc and the sixth surface 81b of the circuit board 81.

[0178] It can be understood that when the buffer structure 82 wraps the side surface 81c of the circuit board 81 close to the selected first side surface 1cc and the junction T between the sixth surface 81b of the circuit board 81, the dimension d7 of the buffer structure 82 along the first direction X is greater than or equal to the thickness d5 of the circuit board 81, corresponding to the second and fourth cases mentioned above.

[0179] It should be noted that when the buffer structure 82 wraps the side surface 81c of the circuit board 81 close to the selected first side surface 1cc and the junction T between the sixth surface 81b of the circuit board 81, the part 8b1 of the outer surface 82a of the buffer structure located on the side of the fourth surface 8b (that is, the part corresponding to the dotted rectangular box in Figure 17B) forms the fourth surface 8b.

[0180] In some embodiments, the material of the buffer structure 82 includes an organic material.

[0181] For example, the material of the buffer structure 82 may be resin or polyimide.

[0182] The above-mentioned organic material is not easy to deform at high temperature. When the buffer material is prepared using the above-mentioned organic material and the connecting lead 3 is prepared through a printing process, the buffer structure 82 is not easy to deform during the high-temperature curing of the initial connecting lead and the high-temperature curing of the initial protective layer, and the conductive paste can climb steadily and slowly along the buffer structure 82.

[0183] In some embodiments, as shown in FIG20 , each back electrode 4 includes a first straight portion 41, a diagonal portion 42, and a second straight portion 43. The first straight portion 41 extends perpendicular to the second direction Y, which is the direction of extension of the boundary between the first selected side surface and the second surface 1b. The diagonal portion 42 is connected to the first straight portion 41, and the direction of extension of the first straight portion 41 intersects the direction of extension of the diagonal portion 42. The second straight portion 43 is connected to the diagonal portion 42 and extends perpendicular to the second direction Y. The second straight portion 43 is further away from the selected first side surface 1cc than the first straight portion 41. The third portion 33 of the connecting lead 3 is electrically connected to the first straight portion 41, and the second straight portion 43 is used to connect to the flexible circuit board 9. The first straight portions 41 of the plurality of back electrodes 4 are arranged along the second direction Y, and the second straight portions 43 of the plurality of back electrodes 4 are arranged along the second direction Y. The dimension D10 of the plurality of second straight portions 43 along the second direction Y is smaller than the dimension D9 of the plurality of first straight portions 41 along the second direction Y.

[0184] The dimension D10 of the plurality of second straight portions 43 along the second direction Y is smaller than the dimension D9 of the plurality of first straight portions 41 along the second direction Y. This allows the plurality of oblique portions 42 connecting the plurality of second straight portions 43 and the plurality of first straight portions 41 to extend toward the centerline O of the fourth surface 8b. The region corresponding to the plurality of oblique portions 42 thus forms the fan-out region SS of the back electrode 4. This allows the plurality of second straight portions 43 to converge inward relative to the plurality of first straight portions 41, resulting in a smaller region corresponding to the plurality of second straight portions 43 than to the region corresponding to the plurality of first straight portions 41, facilitating electrical connection to the flexible printed circuit board 9.

[0185] 20 , the minimum dimension D11 of the bridge structure 8 along the second direction Y is the dimension D9 of the plurality of first straight portions 41 along the second direction Y. The maximum dimension D11 of the bridge structure 8 along the second direction Y is (M-30 μm), where M is the dimension of the substrate 1 along the second direction Y.

[0186] For example, as shown in FIG20 , the dimension D12 of the bridge structure 8 along the third direction Z ranges from 3 mm to 50 mm. This dimension range is appropriately selected so that the area of ​​the fourth surface 8 b of the bridge structure 8 is sufficient for the plurality of oblique portions 42 to form the fan-out region SS of the back electrode 4. The dimension D12 of the bridge structure 8 along the third direction Z ranges from 3 mm to 50 mm, for example.

[0187] In some examples, as shown in FIG1 , the second straight portion 43 is directly electrically connected to the flexible circuit board 9, or the second straight portion 43 is electrically connected to the flexible circuit board 9 via external leads. The flexible circuit board 9 is, for example, a COF (Chip On Film) flexible circuit board 9.

[0188] In some examples, as shown in FIG21 , a fourth distance L4 is defined between the first straight portion 41, which is located near the edge of the selected first side surface 1cc, and the intersection of the selected second side surface 8cc and the fourth surface 8b. The fourth distance L4 ranges from 0 to 1 mm. Examples of the fourth distance L4 include 0 mm, 0.5 mm, and 1 mm.

[0189] 21 , the length D13 of the first straight portion 41 along its extending direction is greater than or equal to 60 μm. The length D13 of the first straight portion 41 along its extending direction is, for example, 60 μm, 80 μm, or 90 μm.

[0190] 21 , the dimension D14 of the first straight portion 41 along the second direction Y is greater than 50 μm. The dimension D14 of the first straight portion 41 along the second direction Y is, for example, 55 μm, 60 μm, or 70 μm.

[0191] Exemplarily, as shown in FIG. 21 , a distance D15 between two adjacent first straight portions 41 is greater than or equal to 100 μm.

[0192] This arrangement can prevent short circuits between two adjacent first straight portions 41 and leave enough space for the protective layer 6 to ensure the protective effect of the protective layer 6. The spacing between two adjacent first straight portions 41 is, for example, 100 μm, 120 μm, or 150 μm.

[0193] On the other hand, as shown in Figures 22A and 22B, a display device 100 is provided, comprising the 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 of the display panel 10 via the flexible circuit board 9. 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 9, the back electrode 4, the connecting traces 3, and the front electrode 2 to control the light-emitting device to emit light. The driver circuit board 20 is configured to drive the display panel 10 to display an image.

[0194] 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.

[0195] 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.

[0196] In another aspect, a spliced ​​display device 1000 is provided, comprising a plurality of display devices 100 provided by any of the aforementioned embodiments.

[0197] Exemplarily, as shown in FIG. 24 and FIG. 26 , the plurality of display devices 100 in the spliced ​​display device 1000 are arranged in an array.

[0198] Exemplarily, as shown in FIG. 24 and FIG. 26 , the display device 100 is, for example, rectangular.

[0199] In the display panel 10, the plurality of front electrodes 22 are arranged in parallel and spaced apart along the second direction Y. Accordingly, the plurality of connecting leads 3 are also arranged in parallel and spaced apart along the second direction Y. The third direction Z is another direction parallel to the display device 100 and perpendicular to the 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 plurality of front electrodes 22 are referred to as selected side surfaces of the display device 100 for description.

[0200] Exemplarily, as shown in FIG23 , 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.

[0201] Furthermore, as shown in FIG24 , when a plurality of display devices 100 including the display panel 10 as shown in FIG23 are spliced ​​together, the selected side surfaces of two adjacent display devices 100 are arranged along the second direction Y. In this way, among the plurality of display devices 100 arranged in a row along the second direction Y, there is basically no splicing seam between two adjacent display devices 100 along the second direction Y; and among the plurality of display devices 100 arranged in a column along the third direction Z, there is a splicing gap between two adjacent display devices 100. That is, among the plurality of display devices 100 arranged in a row along the second direction Y, the size of the splicing gap between two adjacent display devices 100 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 third direction Z.

[0202] However, the size of the binding area BB in the third direction Z is very small. Therefore, when the spliced ​​display device 1000 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 1000 is more complete and can present a better display effect.

[0203] Exemplarily, as shown in FIG. 25 , 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 22 are provided in the binding area BB.

[0204] Furthermore, as shown in FIG26 , when a plurality of display devices 100 including the display panel 10 as shown in FIG25 are spliced ​​together, the selected side surfaces of two adjacent display devices 100 are arranged along the second direction Y. In this way, among the plurality of display devices 100 arranged in a row along the second direction Y, there is basically no splicing seam between two adjacent display devices 100 along the second direction Y; and among the plurality of display devices 100 arranged in a column along the third direction Z, there is a splicing gap between two adjacent display devices 100. That is, among the plurality of display devices 100 arranged in a row along the second direction Y, the size of the splicing gap between two adjacent display devices 100 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 third direction Z.

[0205] However, the size of the binding area BB in the third direction Z is very small. Therefore, when the spliced ​​display device 1000 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 1000 is more complete and can present a better display effect.

[0206] In another aspect, a method for manufacturing a display panel 10 is provided. As shown in FIG27 , the method for manufacturing the display panel 10 includes:

[0207] R1: Provide initial substrate.

[0208] R2: forming a front film layer structure on the front side of the initial substrate.

[0209] Exemplarily, the front film layer structure includes a driving circuit layer.

[0210] R3: forming a plurality of front electrodes 2 arranged in parallel and spaced apart on the front surface of the initial substrate.

[0211] R4: Cutting the initial substrate to form a plurality of substrates 1; the substrate 1 includes a first surface 1a and a second surface 1b 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.

[0212] 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.

[0213] R5: A bridging structure 8 is disposed on the second surface 1b of the substrate 1. The bridging structure 8 includes a third surface 8a and a fourth surface 8b disposed opposite each other, and a plurality of second side surfaces 8c connecting the third surface 8a and the fourth surface 8b. The third surface 8a is closer to the substrate 1 than the fourth surface 8b. The plurality of second side surfaces 8c include at least one selected second side surface 8cc. Each selected second side surface 8cc corresponds to a selected first side surface 1cc. A first spacing L1 is defined between the third surface 8a and the fourth surface 8b. A first common edge H is the intersection of the selected second side surface 8cc and the fourth surface 8b, and a second common edge N is the intersection of the selected second side surface 8cc and the third surface 8a. A second spacing L2 is defined between the orthographic projection of the first common edge H on the third surface 8a and the orthographic projection of the second common edge N on the third surface 8a. The ratio of the first spacing L1 to the second spacing L2 is between 0.27 and 1.73. The distance between the second common edge N and the first selected side surface is a third spacing L3, and the value of the third spacing L3 ranges from 0.5 mm to 2.0 mm.

[0214] The process of connecting the bridge structure 8 to the fourth surface 8 b of the substrate 1 is, for example, high-precision bonding, so that the back electrode 4 and the front electrode 2 face each other in the first direction X.

[0215] Before R5, a plurality of back electrodes 4 are formed on the fourth surface 8b of the bridge structure 8, and the plurality of back electrodes 4 are close to the selected second side surface 8c. Exemplarily, the plurality of back electrodes are formed by a wet etching process.

[0216] R6: A plurality of connecting leads 3 are formed that are arranged in parallel and at intervals; each connecting lead 3 among the plurality of connecting leads 3 includes a first portion 31 located on one side of the first surface 1a, a second portion 32 located on one side of the selected first side surface 1cc, and a third portion 33 located on one side of the second surface 1b; the third portion 33 of each connecting lead 3 is electrically connected to a back electrode 4; the third portion 33 of the connecting lead 3 includes a portion located on the second surface 1b, a portion located on the selected second side surface 8cc, and a portion located on one side of the fourth surface 8b.

[0217] Exemplarily, the process for forming the plurality of connecting leads 3 is a printing process, such as screen printing, pad printing, transfer printing, and 3D printing.

[0218] In some embodiments, the method for manufacturing the display panel 10 further includes, after step R6:

[0219] R7: A protective layer 6 is formed on a side of the connecting lead 3 away from the selected second side surface 8cc.

[0220] R8: forming a light-blocking layer 7 on a side of the protective layer 6 away from the selected second side surface 8 cc and on a side of the first surface 1 a of the substrate 1 .

[0221] In some other embodiments, when the bridge structure 8 includes a circuit board 81 and a buffer structure 82, step R4 includes:

[0222] R4.1: Attach the circuit board 81 to the second surface 1 b of the substrate 1 .

[0223] The process of connecting the circuit board 81 to the fourth surface 8 b of the substrate 1 is, for example, high-precision bonding, so that the back electrode 4 and the front electrode 2 face each other in the first direction X.

[0224] R4.2: Buffer structure 82 is formed on the side surface of wiring board 81 close to the selected first side surface 1 cc.

[0225] The above-mentioned process for forming the buffer structure 82 is, for example, screen printing, pad printing, transfer printing and 3D printing.

[0226] 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.

[0227] 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 arranged opposite to each other, and a plurality of first side surfaces connecting the first surface and the second surface; The plurality of first side surfaces include at least one selected first side surface; a bridge structure disposed on the second surface; the bridge structure includes a third surface and a fourth surface disposed opposite to each other, and a plurality of second side surfaces connecting the third surface and the fourth surface; the third surface is closer to the substrate than the fourth surface; the plurality of second side surfaces include at least one selected second side surface; each selected second side surface corresponds to a selected first side surface; A plurality of back electrodes are arranged in parallel and at intervals on the fourth surface; A plurality of connecting leads, the plurality of connecting leads are arranged in parallel and spaced apart; each connecting lead comprises a first portion located on one side of the first surface, a second portion located on one side of the selected first side surface, and a third portion located on one side of the second surface; the third portion of each connecting lead is electrically connected to a back electrode; the third portion of the connecting lead comprises a portion located on the second surface, a portion located on the selected second side surface, and a portion located on one side of the fourth surface; the third surface and the fourth surface have a first interval; The first common edge is the intersection line of the selected second side surface and the fourth surface, the second common edge is the intersection line of the selected second side surface and the third surface, the orthographic projection of the first common edge on the third surface and the orthographic projection of the second common edge on the third surface have a second interval, and the ratio of the first interval to the second interval is 0.27 to 1.73; The distance between the second common edge and the first selected side surface is a third interval, and the value range of the third interval is 0.5 mm to 2.0 mm.

2. The display panel according to claim 1, wherein: The portion of the connecting lead corresponding to the area where the fourth surface is located has a first thickness, the portion of the connecting lead corresponding to the area where the second surface is located has a second thickness, and the portion of the connecting lead corresponding to the selected second side surface has a third thickness; Among them, the first thickness is greater than or equal to the second thickness, and the difference between the first thickness and the second thickness is 0 to 1 μm; the third thickness is greater than the first thickness or the second thickness, and the difference between the third thickness and the first thickness or the second thickness is 1 μm to 3 μm.

3. The display panel according to claim 1 or 2, wherein: A cross section of the selected second side surface that is perpendicular to the first common edge or the second common edge is a straight line segment, a curve segment, or a broken line segment, and the curve segment bends away from the second surface.

4. The display panel according to any one of claims 1 to 3, wherein: The selected second side surface is a plane, and the angle between the selected second side surface and the third surface is in the range of 10° to 80°.

5. The display panel according to any one of claims 1 to 3, wherein: The selected second side surface includes a plurality of sub-surfaces connected in sequence; Of the two adjacent sub-surfaces, the sub-surface that is further away from the selected first side surface is further away from the second surface than the other sub-surface.

6. The display panel according to claim 5, wherein: The plurality of sub-surfaces are planes, and the selected second side surface is stepped; The selected second side surface includes at least two first sub-surfaces and at least one second sub-surface that are alternately arranged, and the sub-surface closest to the fourth surface and the sub-surface closest to the second surface among the multiple sub-surfaces are both first sub-surfaces; The at least two first sub-surfaces are parallel to the selected first side surface; and / or The second sub-surface is parallel to the second surface.

7. The display panel according to claim 6, wherein: The dimensions of the orthographic projections of the at least two first sub-surfaces on the first reference plane in the first direction are both the first dimensions; the first reference plane is parallel to the selected first side surface; The first direction is the thickness direction of the substrate; and / or The dimensions of the orthographic projection of the at least one second sub-surface on the second reference plane in the third direction are all the second dimensions; the second reference plane is parallel to the second surface; and the third direction is perpendicular to the selected first side surface.

8. The display panel according to any one of claims 1 to 7, wherein: The bridging structure comprises: A circuit board, comprising a fifth surface and a sixth surface arranged opposite to each other, and a plurality of third side surfaces connecting the fifth surface and the sixth surface, wherein the plurality of third side surfaces include at least one selected third side surface; the selected third side surface serves as the selected second side surface; and the plurality of back electrodes are arranged in parallel and at intervals on the sixth surface.

9. The display panel according to claim 8, wherein: The circuit board comprises an adhesive layer and a carrier body which are stacked, and the adhesive layer is close to the substrate relative to the carrier body; The selected third side surface of the circuit board is stepped, and the distance between the end of the carrier body close to the selected first side surface and the selected first side surface is smaller than the distance between the end of the adhesive layer close to the selected first side surface and the selected first side surface.

10. The display panel according to claim 9, wherein: The ratio of the thickness of the adhesive layer to the thickness of the carrier body is in the range of 1.4 to 1.

6.

11. The display panel according to any one of claims 1 to 10, wherein: The bridging structure comprises: A circuit board; the circuit board comprises a fifth surface and a sixth surface arranged opposite to each other, and a plurality of third side surfaces connecting the fifth surface and the sixth surface; the plurality of back electrodes are arranged in parallel and spaced relation on the sixth surface; The buffer structure is located on a side of the circuit board close to the selected first side surface; the outer surface of the buffer structure serves as at least a part of the selected second side surface, and the outer surface of the buffer structure is the surface of the buffer structure away from the circuit board and the second surface.

12. The display panel according to claim 11, wherein: The buffer structure includes a plurality of first sub-buffer structures, and at least a portion of each connecting lead is correspondingly arranged on a first sub-buffer structure among the plurality of first sub-buffer structures.

13. The display panel according to claim 11, wherein: The multiple connecting leads include multiple groups of connecting leads, each group of connecting leads includes at least two connecting leads; the buffer structure includes multiple second sub-buffer structures, and at least a portion of each group of connecting leads is correspondingly arranged on a second sub-buffer structure among the multiple second sub-buffer structures.

14. The display panel according to claim 11, wherein: The buffer structure extends along a second direction, which is an extension direction of a boundary line between the first selected side surface and the second surface, and a length of the buffer structure is greater than a distance between outer sides of two outermost connecting leads in an orthographic projection of the plurality of connecting leads on the second surface, wherein the outer sides of the two connecting leads are side sides of the two connecting leads that are away from each other.

15. The display panel according to any one of claims 11 to 14, wherein: The cross-section of the surface of the buffer structure away from the circuit board and the second surface that is perpendicular to the first common edge or the second common edge is a straight line segment, a curve segment or a broken line segment, and the curve segment bends away from the second surface; or, the surface of the buffer structure away from the circuit board and the second surface includes a plurality of sub-surfaces connected in sequence.

16. The display panel according to any one of claims 11 to 15, wherein: The buffer structure further wraps a boundary portion between a side surface of the circuit board close to the selected first side surface and a sixth surface of the circuit board.

17. The display panel according to any one of claims 11 to 16, wherein: The material of the buffer structure includes organic material.

18. The display panel according to any one of claims 1 to 17, wherein: The dimension of the end of the connecting lead located on the second surface and close to the bridging structure in the second direction is greater than the dimension of the other parts of the connecting lead in the second direction; the second direction is the extension direction of the boundary line between the first selected side surface and the second surface.

19. The display panel according to any one of claims 1 to 18, wherein: Each of the back electrodes comprises: a first straight portion extending in a direction perpendicular to a second direction; the second direction being an extending direction of a boundary line between the first selected side surface and the second surface; an oblique line portion connected to the first straight line portion, wherein an extending direction of the first straight line portion intersects with an extending direction of the oblique line portion; a second straight line portion connected to the oblique line portion and extending in a direction perpendicular to the second direction; the second straight line portion is farther away from the selected first side surface than the first straight line portion; The third portion of the connecting lead is electrically connected to the first straight portion, and the second straight portion is used to connect to the flexible circuit board; The first straight line portions of the plurality of back electrodes are arranged along the second direction, the second straight line portions of the plurality of back electrodes are arranged along the second direction, and the size of the plurality of second straight line portions along the second direction is smaller than the size of the plurality of first straight line portions along the second direction.

20. A display device, comprising: The display panel according to any one of claims 1 to 19; 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.

21. A spliced ​​display device, comprising a plurality of display devices according to claim 20.

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