Display panel, display device and tiled display device

Abstract

The embodiment of the invention provides a display panel, a display device and a tiled display device, relates to the technical field of display, and is used for solving the problem of breakage of wires prepared at offset positions of the display panel. The display panel comprises a substrate, a bridging structure, a plurality of back electrodes and a plurality of connecting wires. The substrate comprises a first surface, a second surface and a plurality of first side surfaces, wherein the first surface and the second surface are oppositely arranged, and at least one of the first side surfaces is a first selected side surface. The bridging structure is arranged on the second surface and comprises a third surface and a fourth surface which are oppositely arranged, and the third surface is close to the substrate relative to the fourth surface; a plurality of grooves are formed in the part, close to the first selected side surface, of the bridging structure; each connecting wire comprises a first wire, a second wire and a third wire, and the third wire comprises a first part, a second part and a third part which are connected in sequence; the second part is located in the groove, and the third part is located on one side of the fourth surface and connected with the back electrode.

Description

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] The use of micro light-emitting diodes (Micro Light-emitting Diode) or sub-millimeter light-emitting diodes (Mini Light-emitting Diode) as pixels of display panels has received extensive attention and research. Currently, due to the mass transfer yield problem, it is impossible to produce large-sized display devices at one time. Usually, a method of splicing small-sized display devices is used to assemble a large-sized spliced ​​display device.

[0003] In order to reduce the border size of the display device and reduce the seam width of the spliced ​​display device, a single display panel can currently use wiring arranged on the side of the display panel to connect the wiring on the display surface with a driver (such as a circuit board or a driver chip) arranged on the non-display surface. When multiple display panels are combined to form a larger spliced ​​display device, the spacing between adjacent display panels can be smaller, thereby improving the display quality. Summary of the invention

[0004] The purpose of the embodiments of the present disclosure is to provide a display panel, a display device and a spliced ​​display device, which are used to reduce the problem of breakage of printed wiring at the step position of the display panel in the direct writing printing process and improve the yield of the display panel.

[0005] To achieve the above objectives, the embodiments of the present disclosure provide the following technical solutions:

[0006] In one aspect, a display panel is provided. The display panel includes a substrate, a bridge structure, a plurality of back electrodes and a plurality of connecting wires. The substrate includes a first surface and a second surface opposite to each other, and a plurality of first side surfaces connecting the first surface and the second surface, at least one of the plurality of first side surfaces being a first selected side surface. The bridge structure is arranged on the second surface, and the bridge structure includes a third surface and a fourth surface opposite to each other, and the third surface is close to the substrate relative to the fourth surface; wherein a plurality of grooves are provided in a portion of the bridge structure stack close to the first selected side surface, and the openings of the plurality of grooves face the first selected side surface. The plurality of back electrodes are arranged in parallel and at intervals on the fourth surface, and each of the plurality of grooves corresponds to a back electrode. The plurality of connecting wires are arranged in parallel and at intervals; each connecting wire includes a first wire located on one side of the first surface, a second wire located on one side of the first selected side surface and a third wire located on one side of the second surface; the third wire includes a first portion, a second portion and a third portion connected in sequence; the second portion is located in the groove, the third portion is located on one side of the fourth surface and connected to the back electrode, and the first portion is located between the second portion and the second wire.

[0007] In the above-mentioned display panel, a groove is opened on the bridging structure, so that the conductive paste can be formed in batches at the step difference during the process of printing and forming the second part, which is equivalent to reducing the vertical height that needs to be formed at a single time, and the larger step difference is decomposed into two smaller step differences. When the conductive paste is formed in the groove, the conductive paste is accumulated and raised, which further reduces the step difference between the surface of the conductive paste and the fourth surface, thereby reducing the difficulty of printing the conductive paste on the side wall of the groove, making the formed connecting line less likely to break. At the same time, since the second part is confined in the groove and does not overflow, the short circuit between the second parts of two adjacent connecting lines is avoided.

[0008] In some embodiments, a dimension of the second portion along the first direction is smaller than dimensions of the first portion and the third portion along the first direction, and the second direction is an extension direction of the third trace.

[0009] In some embodiments, the second portion includes a first sub-portion and a second sub-portion, the average distance between the second sub-portion and the second surface is greater than the average distance between the first sub-portion and the second surface, and the second sub-portion is connected to the third portion; the size of the first sub-portion in the second direction is greater than the size of the second sub-portion in the second direction, and the second direction is the extension direction of the third routing.

[0010] In some embodiments, the thickness of the first sub-portion is greater than or equal to the thickness of the first portion, and the thickness of the first sub-portion is greater than the thickness of the third portion.

[0011] In some embodiments, a thickness of a portion of the first portion proximate to the bridging structure is greater than a thickness of a portion of the first portion proximate to the first selected side surface.

[0012] In some embodiments, a size of the groove in a first direction is smaller than a size of the back electrode in the first direction, and the first direction is perpendicular to an extension direction of the third trace.

[0013] In some embodiments, a ratio of a size of the groove in the first direction to a size of the back electrode in the first direction ranges from 0.5 to 0.6.

[0014] In some embodiments, on a plane parallel to and perpendicular to the second direction Y, the groove has multiple cross-sections, and the cross-section farthest from the first selected side surface among the multiple cross-sections has a size in the first direction that is less than or equal to the size of the cross-section closest to the first selected side surface among the multiple cross-sections in the first direction, and the second direction is the extension direction of the third routing line.

[0015] In some embodiments, the orthographic projection of the groove on the second surface is in the shape of a square, a trapezoid, or a semi-ellipse.

[0016] In some embodiments, a buffer structure is disposed at a side wall of the groove close to the back electrode, the second portion is located in the groove and a portion of the second portion is located on the buffer structure.

[0017] In some embodiments, the groove and the corresponding back electrode have a first spacing in a second direction, and the second direction is an extension direction of the third wiring; the ratio of the size of the groove in the second direction to the first spacing ranges from 0.6 to 1.

[0018] In some embodiments, a side of the bridging structure close to the first selected side surface has a second distance from the first selected side surface in a second direction, and the second direction is an extension direction of the third trace.

[0019] In another aspect, a display device is provided, comprising: a display panel as described in any of the above embodiments and a driving circuit board, wherein the driving circuit board is electrically connected to the display panel, and the driving circuit board is configured to drive the display panel to display an image.

[0020] The above-mentioned display device has the same structure and beneficial technical effects as the display panels provided in some of the above-mentioned embodiments, which will not be described in detail here.

[0021] In another aspect, a spliced ​​display device is provided, comprising: a plurality of display devices as described in the above embodiments spliced ​​together.

[0022] In another aspect, a spliced ​​display device is provided, comprising: a plurality of spliced ​​display panels as described in any one of the above embodiments.

[0023] The above-mentioned spliced ​​display device has the same structure and beneficial technical effects as the display devices provided in some of the above-mentioned embodiments, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the present disclosure, the following briefly introduces the drawings required to be used in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the product involved in the embodiments of the present disclosure, the actual process of the method, the actual timing of the signal, etc.

[0025] Figure 1 is a cross-sectional structural diagram of a display panel according to some embodiments;

[0026] Figure 2 is a planar structural diagram of a display panel according to some embodiments;

[0027] Figure 3 is another cross-sectional structural diagram of a display panel according to some embodiments;

[0028] Figure 4 is a partial top view of the structure of a display panel according to some embodiments;

[0029] Figure 5 is a partial top view of the structure of a display panel according to some embodiments;

[0030] Figure 6 is a partial top view of the structure of a display panel according to some embodiments;

[0031] Figure 7 is another cross-sectional structural diagram of a display panel according to some embodiments;

[0032] Fig. 8A is another cross-sectional structural diagram of a display panel according to some embodiments;

[0033] Figure 8B is a cross-sectional structural diagram of some connecting wires of a display panel according to some embodiments;

[0034] Fig. 9is another cross-sectional structural diagram of a display panel according to some embodiments;

[0035] Fig. 10A is a top view of a groove of a display panel according to some embodiments;

[0036] Fig. 10B is another top view of a groove of a display panel according to some embodiments;

[0037] Fig. 10C is another top view of a groove of a display panel according to some embodiments;

[0038] Fig. 10D is another top view of a groove of a display panel according to some embodiments;

[0039] Fig.10E is another top view of a groove of a display panel according to some embodiments;

[0040] Fig.10F is another top view of a groove of a display panel according to some embodiments;

[0041] Fig.11A is a cross-sectional structural diagram of a display panel according to some embodiments;

[0042] Fig. 11B is another cross-sectional structural diagram of a display panel according to some embodiments;

[0043] Fig.12 is a partial top view of the structure of a display panel according to some embodiments;

[0044] Fig.13 is a cross-sectional structural diagram of a display panel according to some embodiments;

[0045] Fig.14A is another cross-sectional structural diagram of a display panel according to some embodiments;

[0046] Fig. 14B is another cross-sectional structural diagram of a display panel according to some embodiments;

[0047] Fig.15 is a planar structural diagram of a display device according to some embodiments,

[0048] Fig.16 is a planar structural diagram of a display device according to some embodiments;

[0049] Fig.17 is a planar structural diagram of a spliced ​​display device according to some embodiments;

[0050] Fig.18is a planar structural diagram of a display device according to some embodiments;

[0051] Fig.19 is a planar structural diagram of a spliced ​​display device according to some embodiments;

[0052] Fig. 20A is a structural diagram corresponding to steps for preparing a display panel according to some embodiments;

[0053] Fig. 20B is a structural diagram corresponding to steps for preparing a display panel according to some embodiments;

[0054] Fig. 20C is a structural diagram corresponding to steps for preparing a display panel according to some embodiments;

[0055] Fig.20D is a structural diagram corresponding to steps for preparing a display panel according to some embodiments;

[0056] Fig.20E is a structural diagram corresponding to steps for preparing a display panel according to some embodiments. DETAILED DESCRIPTION

[0057] 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 described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present disclosure.

[0058] Unless the context requires otherwise, throughout the specification and claims, the term "comprise" and other forms thereof, such as the third person singular form "comprises" and the present participle form "comprising", are to be interpreted as open, 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" and the like are intended to indicate that specific 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 specific features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0059] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, 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.

[0060] When describing some embodiments, the expressions "coupled" and "connected" and their derivatives may be used. The term "connected" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. The term "coupled" indicates, for example, that two or more components are in direct physical or electrical contact. The term "coupled" or "communicatively coupled" may also refer to two or more components that are not in direct contact with each other, but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this document.

[0061] “At least one of A, B, and C” has the same meaning as “at least one of A, B, or C” and both include the following combinations of A, B, and C: only A, only B, only C, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B, and C.

[0062] "Group A and / or Group B, including the following three combinations: A only, B only, and a combination of A and B.

[0063] As used herein, the term "if" is optionally interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined that" or "if [a stated condition or event] is detected" are optionally interpreted to mean "upon determining that" or "in response to determining that" or "upon detecting [a stated condition or event]" or "in response to detecting [a stated condition or event]," depending on the context.

[0064] The use of "adapted to" or "configured to" herein is meant to be open and inclusive language that does not exclude devices adapted or configured to perform additional tasks or steps.

[0065] Additionally, the use of “based on” is meant to be open and inclusive, as a process, step, calculation, or other action “based on” one or more stated conditions or values ​​may, in practice, be based on additional conditions or values ​​beyond those stated.

[0066] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of variation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0067] 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 the acceptable deviation range, wherein the acceptable deviation range is 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 a particular 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 brackets; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity can also be, for example, a deviation within 5 brackets. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality can be, for example, the difference between the two equalities is less than or equal to 5% of either one.

[0068] It will be understood that when a layer or an 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 between the layer or element and the other layer or substrate.

[0069] Exemplary embodiments are described herein with reference to cross-sectional views and / or plan views that are idealized exemplary drawings. In the drawings, the thickness of the layers and the area of ​​the regions are exaggerated for clarity. Therefore, variations in the shapes relative to the drawings due to, for example, manufacturing techniques and / or tolerances are conceivable. Therefore, the exemplary embodiments should not be interpreted as being limited to the shapes of the regions shown herein, but include shape deviations 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 shapes of the regions of the device, and are not intended to limit the scope of the exemplary embodiments.

[0070] 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.

[0071] In order to avoid the sense of display screen fragmentation caused by splicing, it is necessary to reduce the frame size of a single small-sized display device and reduce the seam width. The small-sized display device includes a display panel. For example, the wiring located on the display surface side of the display panel can be connected to the circuit board (such as a flexible circuit board) arranged on the non-display surface side of the display panel through side wiring. Therefore, when multiple small-sized display devices are spliced ​​to form a larger large-sized display device, the spacing between adjacent small-sized display devices can be smaller, so that the seam width of the large-sized display device formed by splicing multiple small-sized display devices is reduced, and the display quality is improved.

[0072] The display panel, display device and spliced ​​display device provided by the present disclosure are introduced respectively below.

[0073] In this disclosure, Figure 1 is a cross-sectional structural diagram of a display panel according to some embodiments, Figure 2 is a planar structural diagram of a display panel according to some embodiments, Figure 3 FIG. 1 is another cross-sectional structural diagram of a display panel according to some embodiments. In order to clearly describe the structural changes of the display panel during the preparation process, Figures 4 to 6 A partial top view of the display panel is shown in FIG. Figure 7 to Figure 9 , Fig.11A , Fig. 11B , Fig.12 , Fig.13 , Fig.14A and Fig. 14B is a cross-sectional structural diagram of a display panel according to some embodiments, Figures 10A to 10F , Fig.12 is a top view of a groove of a display panel according to some embodiments. Fig.15 , Fig.16 , Fig.18 is a planar structural diagram of a display device 100 according to some embodiments, Fig.17 , Fig.19 is a planar structural diagram of a spliced ​​display device 200 according to some embodiments, Figures 20A to 20E is a structural diagram corresponding to steps for preparing a display panel according to some embodiments.

[0074] In some embodiments, Figure 1As shown, the display panel 10 includes a substrate 1, a plurality of front electrodes 2, a plurality of connecting wires 3 and a plurality of back electrodes 4. 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, and at least one of the plurality of first side surfaces 1c of the substrate 1 is a first selected side surface 1cc. A plurality of connecting wires 3 are correspondingly arranged on each first selected side surface 1cc, and the plurality of connecting wires 3 are arranged in parallel and spaced apart; each connecting wire 3 extends from the first surface 1a through the first selected side surface 1cc to the second surface 1b, that is, each connecting wire 3 includes a first wire 31 located on one side of the first surface 1a, a second wire 32 located on one side of the first selected side surface 1cc and a third wire 33 located on one side of the second surface.

[0075] For example, Figure 1 and Figure 2 As shown, one side of the first surface 1a of the substrate 1 is the front of the display panel 10, and one side of the first surface 1a of the substrate is provided with a display area AA and a binding area BB. A film layer structure such as a drive circuit layer and a light-emitting device layer 5 is provided in the display area AA. The light-emitting device layer 5 includes light-emitting devices 51 of at least three colors, and the light-emitting devices of multiple colors include at least a first color light-emitting device 511, a second color light-emitting device 512, and a third color light-emitting device 513, wherein the first color, the second color, and the third color are three primary colors (for example, red, green, and blue). Exemplarily, the light-emitting device 51 is a Micro LED (Micro Light Emitting Diode) and a Mini LED (Mini Light Emitting Diode).

[0076] like Figure 1 and Figure 2 As shown, one side of the first surface 1a of the substrate 1 is the front side of the display panel 10, and a plurality of front electrodes 2 can be arranged in the binding area BB and arranged in parallel and spaced relation along a first direction X, and the first direction X is a direction parallel to the boundary line between the first selected side surface 1cc and the first surface 1a. The plurality of front electrodes 2 are electrically connected to at least a portion of the driving circuit layer (not shown in the figure). The first wiring 31 of the plurality of connecting wirings 3 is located on one side of the first surface 1a of the substrate 1, and is electrically connected to the plurality of front electrodes 2 in a one-to-one correspondence. The extension direction of the first wiring 31 of the plurality of connecting wirings 3 is, for example, a direction perpendicular to the first selected side surface 1cc of the substrate 1, that is, Figure 1 The second direction Y shown in .

[0077] For example, continue to refer to Figure 1, the second surface 1b side of the substrate 1 is the back side of the display panel 10, and the third wiring 33 of the plurality of connecting wirings 3 is located on the second surface 1b side of the substrate 1, that is, the third wiring 33 of the connecting wiring 3 is the portion of the connecting wiring 3 located on the back side of the display panel 10. The extension direction of the third wiring 33 of the plurality of connecting wirings 3 is, for example, the second direction Y. The plurality of back electrodes 4 are disposed on the second surface 1b side of the substrate and are arranged in parallel and spaced relation along the first direction X. The plurality of back electrodes 4 can be used as binding electrodes for connecting a flexible circuit board, and the third wiring 33 of the plurality of connecting wirings 3 is electrically connected to the plurality of back electrodes 4 in a one-to-one correspondence.

[0078] The manufacturing method of the display panel 10 includes: forming a driving circuit layer on the first surface 1a side of the substrate 1, the driving circuit layer including a plurality of front electrodes 2; and forming a plurality of back electrodes 4 on the second surface 1b side of the substrate 1. The process for forming the driving circuit layer is, for example, an etching process, and the process for forming the plurality of back electrodes 4 is, for example, laser etching.

[0079] 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. Moreover, when the orthographic projections of the plurality of back electrodes 4 on the substrate 1 overlap with the area corresponding to the display area AA, the laser may pass through the substrate 1 and enter the display area AA of the first surface 1a, so part of the energy of the laser will pass through the substrate 1 to reach the display area AA and damage the film layer and devices in the display area AA, resulting in reliability issues such as local corrosion and failure of the light-emitting device to light up.

[0080] In other examples, during the production process of the substrate 1, the devices on the front side of the substrate are prepared first, and then the devices on the back side of the substrate are prepared through a flipping process. During the process of flipping the substrate, the substrate contact equipment is easily scratched and contaminated, and static electricity cannot be released, affecting the yield and quality of the product.

[0081] Therefore, in order to reduce the manufacturing cost of the display panel 10 and avoid the influence of the back process of the substrate 1 on the front film layer and the device, in some embodiments, such as Figure 1 and Figure 3 As shown, the display panel 10 further includes a bridge structure 6 disposed on the second surface 1b of the substrate 1; the bridge structure 6 includes a third surface 6a and a fourth surface 6b disposed opposite to each other, and a plurality of second side surfaces 6c connecting the third surface 6a and the fourth surface 6b; the third surface 6a is closer to the substrate 1 than the fourth surface 6b; at least one second side surface 6c among the plurality of second side surfaces 6c is a second selected side surface 6cc; each second selected side surface 6cc corresponds to a first selected side surface 1cc;

[0082] like Figure 1As shown, by setting a bridge structure 6 on the second surface 1b of the substrate 1, the bridge structure 6 can be used as a carrier of multiple back electrodes 4. In the case where the display panel 10 includes a bridge structure 6, the formation of multiple back electrodes 4 can be achieved by the following two steps: first, multiple back electrodes 4 are formed on the fourth surface 6b of the bridge structure 6, and then the bridge structure 6 is connected to the second surface 1b of the substrate 1 with high precision, so that the second surface 1b of the substrate 1 is in contact with the third surface 6a of the bridge structure 6, and at the same time, the front electrode 2 and the back electrode 4 are facing each other in the third direction Z. The above-mentioned process of connecting the bridge structure 6 to the second surface 1b of the substrate 1 with high precision is, for example, bonding. Through the above method, the cost can be reduced, and the influence of the etching process on the front film layer and the device can be avoided.

[0083] In some embodiments, Figure 1 As shown, the back electrode 4 includes a first end 41 close to the first selected side surface 1cc, and a second end 42 away from the first selected side surface 1cc, wherein the first end 41 is used to connect to the connecting trace 3, for example, the connecting trace is overlapped on the first end 41, and the second end is used to connect to a circuit board or a flexible circuit board, for example, the circuit board or the flexible circuit board is overlapped on the second end 42.

[0084] Exemplarily, the bridge structure 6 may further include an insulating layer 9 located on a side of the fourth surface of the back electrode 4 away from the bridge structure, and the insulating layer 9 at least exposes the first end 41 and the second end 42 of each back electrode 4 .

[0085] The insulating layer covers the middle part of the back electrode to protect the back electrode and prevent the back electrode from being corroded. The insulating layer exposes the first end and the second end of each back electrode so that the back electrode 4 is connected to the connection line 3 and the circuit board / flexible circuit board.

[0086] It should be noted that each of the above-mentioned second selected side surfaces 6cc corresponds to one first selected side surface 1cc, which means that the number of second selected side surfaces 6cc and first selected side surfaces 1cc corresponds to each other, and the second selected side surface 6cc is close to the corresponding first selected side surface 1cc, and the two are arranged along the third direction Z.

[0087] In some embodiments, Figure 1 and Figure 3 As shown, when the display panel 10 includes a bridging structure 6, the third wiring 33 of the connecting wiring 3 extends from the second surface 1b of the substrate 1 to the fourth surface 6b of the bridging structure 6, that is, the third wiring 33 is arranged on the second selected side surface 6cc and the fourth surface 6b of the bridging structure 6, and is electrically connected to the second electrode 4.

[0088] The preparation process of the above-mentioned multiple connecting traces 3 is: forming the second trace 32, the first trace 31 and the third trace 33 on the first selected side surface 1cc of the substrate 1, the first surface 1a of the substrate 1 and the second surface 1b of the substrate 1 respectively, for example, using a printing process to form the conductive paste in the printing device on the area corresponding to the need to print the connecting traces, illustratively, the conductive paste is sequentially formed on the first surface 1a, the first selected side surface 1cc, the second surface 1b, the second selected side surface 6cc and the fourth surface 6b of the substrate 1, the printing process can be, for example, a three-dimensional printing process, and the conductive paste can be, for example, a silver paste. The three-dimensional printing process is to use a needle with a certain caliber and air pressure to squeeze the conductive paste in the needle tube to a specific position on the substrate, and the conductive paste will form traces after solidification. Since the connection trace 3 includes parts located on different surfaces, each connection trace 3 needs to be formed separately by printing in batches, for example, it can be printed in three batches to form the parts located on the first surface 1a, the parts located on the first selected side surface 1cc, and the parts located on the second surface 1b, the second selected side surface 6cc and the fourth surface 6b. Exemplarily, the printing process is as follows: the substrate is set on the substrate carrier, the substrate carrier moves along the second direction Y (moves left and right), the printing needle P is set along the third direction Z, keeps a fixed position in the second direction Y, the printing needle moves in the third direction Z (moves up and down), and the ejection speed of the printing needle P is kept constant. By controlling the moving speed of the substrate carrier in the second direction Y and the moving speed of the printing needle P in the third direction X, the distance between the printing needle and the substrate surface is controlled to realize that the conductive paste is smeared on the substrate surface, and after curing, a connection trace with relatively consistent width and thickness is formed, and a good climbing morphology is provided at the step difference of the bridge structure.

[0089] There are certain difficulties in the process of forming the connection lines on the second surface 1b, the second selected side surface 6cc and the fourth surface 6b by printing. On the one hand, since the conductive paste has a certain fluidity, when the substrate carrier moves slowly, it is easy to cause the conductive paste to accumulate, making the final formed lines wider. After printing, the distance between two adjacent lines in the first direction X is too close, which is easy to short-circuit and cause a short circuit. For example, Figure 3As shown, in the process of forming the connection line located on the second surface 1b, the second selected side surface 6cc and the fourth surface 6b by printing, the print needle P is always placed parallel to the third direction Z, and the relative movement path of the print needle P and the substrate carrier is as indicated by the dotted arrow. The specific position of the second surface 1b of the substrate 1 is used as the starting printing position, and the print needle P is located above the starting position to start printing. The print needle maintains a constant coating speed and continues to spit out the material. The substrate carrier moves a specific distance to the left (F1 direction) along the second direction Y, so that the print needle P moves relatively from the starting position to the bridge structure 6 close to the first selected side surface 1c c, the substrate carrier continues to move in the direction of F1, and at this time the print head P slowly moves upward along the third direction Z (along the direction of F2) so that the print head P moves to print just above the fourth surface 6b of the bridging structure 6. That is to say, in the process of the print head P printing from the end face close to the first selected side surface 1cc to just above the fourth surface 6b of the bridging structure 6, the relative movement path of the print head P and the substrate carrier is as indicated by the dotted arrow, and then the print head P continues to maintain this position for printing, and the substrate 1 continues to move a specific distance relative to the print head P in the direction of F1 until printing is completed, and the print head P is closed. Since the bridging structure has a certain thickness and there is a large step difference between the second surface and the fourth surface, in order to ensure that the conductive paste will not break after curing, when printing to the step difference position, the movement speed of the substrate carrier along the second direction Y slows down, so that the printing needle stays longer. Therefore, the conductive paste will accumulate at this position, and after the conductive paste is cured, the risk of contact between two adjacent connecting wires 3 at this position is greatly increased, which can easily cause a short circuit between the two adjacent connecting wires 3, thereby affecting the reliability of the display panel.

[0090] On the other hand, refer to Figure 3 In the case where the second selected side surface 6cc of the bridging structure 6 is perpendicular to the second surface 1b, in the process of forming multiple connecting traces 3, since the fourth surface 6b of the bridging structure 6 and the second surface 1b of the substrate 1 are not in the same horizontal plane, the two constitute a step structure, and the size of the second selected side surface 6cc in the third direction Z is greater than the spitting thickness of the printing needle. Therefore, it is more difficult to set the conductive paste on the second surface 1b by printing. At the same time, due to the influence of gravity and the leveling characteristics of the conductive paste, the conductive paste will accumulate at the bottom of the step position, but it may still be relatively thin at the junction of the second selected side surface 6cc and the fourth surface 6b. At the same time, since the conductive paste will deform during the curing process, such as volume shrinkage, the formed connecting traces 3 are prone to breakage at the junction of the second selected side surface 6cc and the fourth surface 6b, which in turn causes the circuit of the display product to be broken, causing the display panel to be unable to display.

[0091] The material spitting thickness of the printing needle is the thickness of the conductive paste printed on the second selected side surface in the third direction. Exemplarily, the ratio of the material spitting thickness of the printing needle to the thickness of the bridge structure in the third direction is 1:20 to 1:10. For example, the ratio of the material spitting thickness of the printing needle to the thickness of the bridge structure in the third direction is 1:20 or 1:10, and the material spitting thickness of the printing needle is 5 μm.

[0092] Based on this, refer to Figures 4 to 6 A portion of the bridging structure 6 close to the first selected side surface 1cc is provided with a plurality of grooves 61, and the openings of the plurality of grooves 61 face the first selected side surface 1cc; a plurality of back electrodes 4 are arranged in parallel and spaced apart on the fourth surface 6b.

[0093] It is understandable that if Figure 3 As shown, the grooves are arranged in a portion of the bridging structure 6 close to the first selected side surface 1cc, and the openings of the plurality of grooves 61 are toward the first selected side surface 1cc, that is, from the top view angle of the display panel, the grooves 61 are recessed from the second selected side surface 6cc toward the second electrode, and from the side view angle of the display panel, the grooves 61 are recessed from the fourth surface 6b toward the third surface 6a.

[0094] Exemplarily, the thickness of the bridging structure 6 in the third direction Z is 100 μm to 150 μm, and the third direction Z is the thickness direction of the substrate 1 .

[0095] Exemplarily, the material of the bridge structure 6 may be glass, polyimide (PI, Polyimide Film) or other materials.

[0096] In some examples, such as Figure 3 As shown, the groove 61 is arranged in the third direction Z, extending from the fourth surface 6 b to the third surface 6 a , that is, the thickness of the groove 61 in the third direction Z is the same as the thickness of the bridging structure 6 in the third direction Z.

[0097] Exemplarily, the groove 61 runs through the entire bridge structure 6 , and the bottom of the groove 61 exposes the second surface 1 b of the substrate 1 .

[0098] In other examples, such as Figure 4 As shown, the groove 61 is arranged to penetrate a portion of the bridging structure 6 along the fourth surface 6b in the third direction Z. At this time, the thickness of the groove 61 in the third direction Z is less than the thickness of the bridging structure 6 in the third direction Z.

[0099] Exemplarily, the groove 61 runs through a portion of the bridging structure 6 , and the bottom of the groove 61 does not expose the second surface 1 b of the substrate 1 .

[0100] In some embodiments, each surface of the groove 61 is parallel to the third direction Z. In other words, each surface of the groove 61 is perpendicular to the second surface 1 b of the substrate 1 .

[0101] In other embodiments, the bottom surface of the groove 61 may have a certain angle with the third direction Z, and the angle ranges from 30° to 60°. The bottom surface of the groove is the surface close to the back electrode, and the bottom surface of the groove has an angle with the third direction. The angle is 30° to 60°, that is, an obtuse angle is formed between the bottom surface of the groove and the second surface 1b of the substrate, and the bottom surface of the groove is an inclined surface, so that during the printing process, it is smoother to reach the fourth surface from the second surface through the bottom surface of the groove, the printing difficulty is reduced, and the connection wiring can be further prevented from being broken.

[0102] In some embodiments, Figure 1 and Figure 6 As shown, in the case where the display panel 10 includes a bridging structure 6, the third wiring 33 of the connecting wiring 3 includes a first part 331, a second part 332 and a third part 333 which are connected in sequence, wherein the second part 332 is located in the groove 61, the third part 333 is located on one side of the fourth surface 6b and is electrically connected to the back electrode 4, and the first part 331 is located between the second part 332 and the second wiring 32.

[0103] Reference Figure 7 , by opening a groove 61 in the portion of the bridge structure 6 close to the first selected side surface 1cc, and the second portion 332 of the third trace 33 is located in the groove 61, that is, in the process of printing the second portion 332, the conductive paste is formed in the groove 61, and the groove 61 can play a certain limiting role on the boundary of the conductive paste forming the second portion 332, and can prevent the conductive paste from diffusing to both sides along the first direction X. As the moving speed of the substrate carrier slows down, it is easy to cause material accumulation in the groove, but because the conductive paste is subject to certain restrictions in the first direction X, the conductive paste can only accumulate along the third direction Z, that is, the thickness of the conductive paste in the third direction Z gradually increases, and when the printing needle P moves from the opening of the groove to the end along the printing path, the conductive paste (such as Figure 8B The corresponding first sub-portion 332a) has filled the bottom of the groove and has a certain thickness, forming a step; the printing needle P slowly moves upward in the third direction Z to continue printing the conductive paste (such as Figure 8BWhen corresponding to the second sub-section 332b), it is equivalent to continuing to print the conductive paste upward on the basis of the conductive paste that has filled the bottom of the groove, and the step difference from the first step to the fourth surface is reduced, which reduces the difficulty of printing and makes the distribution of the conductive paste more uniform. Compared with the case where the groove 61 is not set, the groove is opened on the bridge structure, and the conductive paste can be formed in batches at the step difference during the process of printing and forming the second part 332, which is equivalent to reducing the vertical height that needs to be formed in a single time, and the larger step difference is decomposed into two smaller step differences in the third direction Z. The conductive paste is easier to print on the bridge structure, and the thickness of the conductive paste at the junction of the second selected side surface 6cc and the fourth surface 6b is thickened, thereby avoiding the problem of fracture during the curing process of the conductive paste due to the large step difference. At the same time, since the second part is confined in the groove and does not overflow, the short circuit phenomenon between the second parts 332 of the two adjacent connecting lines 3 is avoided.

[0104] like Figure 5 As shown, when the groove 61 penetrates part of the bridging structure 6 along the third direction Z and the bottom of the groove 61 does not expose the second surface 1b of the substrate 1, a first step is formed between the bottom of the groove 61 and the second surface of the substrate, and a second step is formed between the bottom of the groove 61 and the fourth surface 6b of the bridging structure 6, decomposing the larger step difference between the second surface 1b and the fourth surface 6b into two smaller step differences. During the printing process, the conductive paste is smeared on the bottom of the groove 61 from the second surface 1b through the first step with a smaller step difference. After filling the bottom of the groove 61, it continues to be smeared on the fourth surface 6b through the second step. Since the groove 61 does not completely penetrate the bridging structure, the step difference between the bottom of the groove 61 and the fourth surface of the bridging structure 6 is reduced. When the conductive paste is formed in the groove, the conductive paste is accumulated and raised, which further reduces the step difference between the surface of the conductive paste and the fourth surface 6b, thereby reducing the difficulty of printing the conductive paste on the side wall of the groove 61, so that the formed connecting trace 3 is not easy to break.

[0105] In some embodiments, reference Figure 6 , a dimension d2 of the second portion 332 along the first direction X is smaller than dimensions of the first portion 331 and the third portion 333 along the first direction X.

[0106] It is understandable that, referring to Figure 6As shown, the first part 331 has a dimension d1 in the first direction X, and the third part 333 has a dimension d3 in the first direction X. Referring to the foregoing content, during the printing process, the conductive paste is coated on the second surface 1b and the fourth surface 6b. Since the conductive paste has a certain fluidity, the conductive paste will level out along the first direction X. Eventually, after curing, the first part 331 and the third part 333 have larger dimensions in the first direction X. Since the second part 332 is located inside the groove 61, which is equivalent to restricting the dimension d2 of the second part 332 in the first direction X. Therefore, the dimension d2 of the second part 332 in the first direction X is narrowed to a certain extent. Thus, the dimension d2 of the second part 332 in the first direction X is smaller than the dimensions of the first part 331 and the third part 333 in the first direction X, that is, d2 < d1 / d3. In this way, even if the conductive paste accumulates at the groove 61, due to the restriction of the groove sidewall, the dimension of the second part 332 in the first direction X will not be too large, avoiding short - circuit between two adjacent third parts 333.

[0107] In some embodiments, as Figure 7 、 Fig. 8A and Figure 8B shown, the second part 332 includes a first sub - part 332a and a second sub - part 332b. The average distance s2 between the second sub - part 332b and the second surface 1b is greater than the average distance s1 between the first sub - part 332a and the second surface 1b, and the second sub - part 332b is connected to the third part 333, and the first sub - part 332a is connected to the first part 331; the dimension d4 of the first sub - part 332a in the second direction Y is greater than the dimension d5 of the second sub - part 332b in the second direction Y, and the second direction Y is the extending direction of the third trace 33.

[0108] It should be noted that, referring to Figure 7 、 Fig. 8A and Figure 8B , the average distance s1 between the second sub - part 332b and the second surface 1b shown in the figure refers to the average value of the distance between the side of the second sub - part 332b away from the second surface 1b and the second surface 1b. The average distance s1 between the first sub - part 332a and the second surface 1b is the average value of the distance between the side of the first sub - part 332a away from the second surface 1b and the second surface 1b. The average distance s2 between the second sub - part 332b and the second surface 1b is greater than the average distance s1 between the first sub - part 332a and the second surface 1b, that is, the second sub - part 332b is farther from the second surface 1b than the first sub - part 332a. The first sub - part 332a is located at the bottom of the groove 61, and the second sub - part 332b is located above the first sub - part 332a and is in contact with the sidewall of the groove 61.

[0109] Exemplarily, referring to Fig. 8A and Figure 8B, the size d4 of the first sub-portion 332a in the second direction Y, the size d5 of the second sub-portion 332b in the second direction Y, the size d4 of the first sub-portion 332a in the second direction Y is greater than the size d5 of the second sub-portion 332b in the second direction Y, according to Fig. 8A and Figure 8B It is known that in Fig. 8A and Figure 8B In the cross-sectional view shown, the second portion 332 formed by the first sub-portion 332a and the second sub-portion 332b is stepped.

[0110] In some embodiments, Fig. 8A and Figure 8B As shown, the thickness t2 of the first sub-portion 332 a is greater than or equal to the thickness t1 of the first portion 331 , and the thickness t2 of the first sub-portion 332 a is greater than the thickness t3 of the third portion 333 .

[0111] It is understandable that, referring to Figure 8B and Fig. 9 In the figure, the first portion 331 located on the second surface 1b includes two parts, namely a straight portion 331a and a slope portion 331b. The thicknesses of the straight portion 331a and the slope portion 331b are different. The thickness t1 of the first portion 331 is the average value of the thickness at each position of the first portion. The straight portion 331a of the third routing line 33 located on the second surface 1b and the third portion 333 located on the fourth surface 6b are both formed without climbing the slope, while the second portion 332 of the third routing line 33 is formed under the climbing state. In the process of forming the first sub-portion 332a, due to the greater printing difficulty and the slower moving speed of the substrate carrier, more conductive paste is accumulated at this position, and the thickness t2 of the first sub-portion 332a formed at this position is greater than the thickness t1 of the first portion 331 and the thickness t3 of the third portion 333.

[0112] In addition, refer to Fig. 9 In the figure, the slope portion 331b located on the second surface 1b is connected to the first sub-portion 332a. During the printing process of the slope portion 331b, it is necessary to climb the slope. Similarly, the moving speed of the substrate stage gradually slows down, resulting in the accumulation of the conductive paste, thus forming Fig. 9 The slope portion 331b shown in the figure, wherein the thickness t2 of the first sub-portion 332a is equal to the thickness of the portion of the slope portion close to the first sub-portion 332a, that is, the portion where the slope portion of the first portion contacts the first sub-portion forms a transition.

[0113] In some embodiments, Fig. 9 As shown, the thickness t12 of the portion of the first portion 331 close to the bridge structure 6 is greater than the thickness t11 of the portion of the first portion 331 close to the first selected side surface 1 cc.

[0114] For example, continue to refer to Fig. 9 As can be seen from the above content, the first portion 331 includes two parts, namely, the straight portion 331a and the slope portion 331b, wherein the portion close to the bridge structure 6 is the slope portion 331b, and the portion close to the first selected side surface 1cc is the straight portion 331a. According to the introduction of the above printing process, the conductive paste accumulates more in the process of forming the slope portion 331b, and it is equivalent to the initial position of the climbing, while in the process of forming the straight portion 331a, there is no climbing, so the thickness t12 of the slope portion 331b is greater than the thickness of the straight portion 331a. The above thicknesses are the average values ​​of the thicknesses of the first portion 331 on the corresponding second surface 1b, and the thickness direction is the third direction Z.

[0115] In some embodiments, reference Fig. 10A , Fig. 10C and Fig.10E A dimension L1 of the groove 61 in the first direction X is smaller than a dimension L2 of the back electrode 4 in the first direction X, and the first direction X is perpendicular to the extension direction of the third wiring 33 .

[0116] It is understandable that according to the above content and in combination with Fig. 9 It can be seen that in the process of printing the third routing of the connecting routing 3, since the fourth surface 6b of the bridging structure 6 and the second surface 1b of the substrate 1 are not in the same horizontal plane, the two form a step structure, and the size of the second selected side surface 6cc in the third direction Z is greater than the spitting thickness of the printing needle, it is difficult to set the conductive paste on the second surface 1b by printing. At the same time, due to the influence of gravity and the leveling characteristics of the conductive paste, the conductive paste will accumulate at the bottom of the step position, but it may still be relatively thin at the junction of the second selected side surface 6cc and the fourth surface 6b. At the same time, since the conductive paste will deform during the curing process, such as volume shrinkage, the formed connecting routing 3 is easy to be formed at the junction of the second selected side surface 6cc and the fourth surface 6b. In order to avoid the breakage of the third wiring 33 of the connecting wiring 3 and reduce the climbing difficulty of the conductive paste during the printing process, the printing method is changed to segmented climbing printing, and the dimension L1 of the groove 61 in the first direction X is set to be smaller than the dimension L2 of the back electrode 4 in the first direction X. In the process of printing the second part 332, as the moving speed of the substrate carrier slows down, the conductive paste is restricted by the groove 61 and can only be accumulated along the third direction Z, that is, the thickness of the second part 332 in the third direction Z is increased, which can decompose the step difference between the bridging structure 6 and the second surface 1b into multiple small step differences to a certain extent, reduce the printing difficulty, and thus avoid the breakage of the formed connecting wiring 3 at the junction of the second selected side surface 6cc and the fourth surface 6b.

[0117] It should be noted that the dimension L1 of the groove 61 in the first direction X is an average dimension of the groove 61 in the first direction X.

[0118] In some embodiments, continue to refer to Fig. 10A , Fig. 10C and Fig.10E , the ratio of the dimension L1 of the groove 61 in the first direction X to the dimension L2 of the back electrode 4 in the first direction X is in the range of 0.5 to 0.6.

[0119] It is understandable that when the difference between the size L1 of the groove 61 in the first direction X and the size L2 of the back electrode 4 in the first direction X is too large, the size of the groove 61 is too narrow, so that the size of the second part is too narrow, which may affect the transmission efficiency of the electrical signal of the connecting line 3, thereby affecting the display of the display panel; if the difference between the size L1 of the groove 61 in the first direction X and the size L2 of the back electrode 4 in the first direction X is too small, the stacking effect will not be obvious in the actual printing process of the connecting line 3, thereby failing to achieve the effect of reducing the step difference. By setting the ratio range of the size L1 of the groove 61 in the first direction X and the size L2 of the back electrode 4 in the first direction X, the difference between the size L1 of the groove 61 in the first direction X and the size L2 of the back electrode 4 in the first direction X can be kept within a reasonable range, ensuring the transmission efficiency of the electrical signal of the display panel, thereby improving the yield of the display panel. Exemplarily, the ratio range of the size L1 of the groove 61 in the first direction X to the size L2 of the back electrode 4 in the first direction X is, for example, 0.5, 0.55 or 0.6.

[0120] In some embodiments, reference Figures 10A to 10F , on a plane parallel to and perpendicular to the second direction Y, the groove 61 has multiple cross-sections, and the cross-section farthest from the first selected side surface 1cc among the multiple cross-sections has a dimension L11 in the first direction X that is less than or equal to the dimension L12 in the first direction X of the cross-section closest to the first selected side surface 1cc among the multiple cross-sections.

[0121] For example, refer to Fig. 10A , the dimension L11 of the section farthest from the first selected side surface 1cc among the multiple sections of the groove 61 in the first direction X is equal to the dimension L12 of the section closest to the first selected side surface 1cc among the multiple sections of the groove 61 in the first direction X, and the positive projection of the groove 61 on the second surface 1b is a rectangle. It can be understood that according to the above content and in combination with Fig. 9It can be seen that in the process of printing the second portion 332 located in the groove 61, the moving speed of the substrate carrier will be slowed down due to the difficulty in climbing the slope, which results in the conductive paste being accumulated at a position farthest from the first selected side surface 1cc of the groove 61 to a higher degree than the conductive paste being accumulated at a position closest to the first selected side surface 1cc of the groove 61. In other words, the thickness of the second portion 332 formed at the position farthest from the first selected side surface 1cc of the groove 61 in the third direction Z is greater than the thickness of the second portion 332 at the position closest to the first selected side surface 1cc of the groove 61. The thickness of the part at the position in the third direction Z, at this time, the orthographic projection of the second portion 332 on the plane perpendicular to the second selected side surface 6cc is a step shape, which is equivalent to reducing the difficulty of climbing once, and decomposing the height difference between the second surface 1b and the fourth surface 6b into multiple small section differences, so as to achieve multiple climbing, and avoid the problem of fracture due to too large height difference during the curing process of the conductive paste. At the same time, due to the limitation of the position of the groove 61 in the first direction X, the size of the conductive paste in the first direction X will not become wider, so as to avoid the short circuit phenomenon of two adjacent connecting lines 3 in the local area.

[0122] For example, refer to Figure 10C to Figure 10FAs described in the above part, since the fourth surface 6b of the bridge structure 6 and the second surface 1b of the substrate 1 are not on the same horizontal plane, the two form a step structure. The step difference from the second surface 1b to the fourth surface 6b is large, which makes it difficult for the conductive paste to climb upright on the second selected side surface 6cc, increasing the difficulty of printing. The dimension L11 of the section farthest from the first selected side surface 1cc among the multiple sections of the groove 61 in the first direction X is set to be smaller than the dimension L12 of the section closest to the first selected side surface 1cc among the multiple sections of the groove 61 in the first direction X. For example, along the direction from the first selected side surface 1cc to the second selected side surface 6cc, the dimension of the groove 61 gradually narrows. In the process of printing by moving the substrate carrier, the conductive paste can be deposited faster at a position far from the first selected side surface 1cc in the groove 61 than at a position close to the first selected side surface 1cc in the groove 61 when the speed of the substrate carrier is the same, and the height of the deposited conductive paste is higher, which can not only improve the printing efficiency, but also It is easier to prepare the stepped second portion 332, and the thickness of the second portion 332 at the position of the groove 61 away from the first selected side surface 1cc in the third direction Z is greater than the thickness of the second portion 332 at the position of the groove 61 close to the first selected side surface 1cc in the third direction Z, which is equivalent to further reducing the difficulty of climbing once, and decomposing the height difference between the second surface 1b and the fourth surface 6b into multiple small section differences, achieving multiple climbing, and avoiding the problem of breakage due to the large height difference during the curing process of the conductive paste. At the same time, due to the limitation of the position of the groove 61 in the first direction X, the size of the conductive paste in the first direction X will not become wider, which can avoid the short circuit phenomenon of two adjacent connecting lines 3 in the local area.

[0123] In some embodiments, reference Figures 10A to 10F The shape of the orthographic projection of the groove 61 on the second surface 1b is a square, a trapezoid or a semi-ellipse.

[0124] For example, refer to Fig. 10A The shape of the positive projection of the groove 61 on the second surface 1b is a square, which can ensure that the dimension L11 of the section farthest from the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X is equal to the dimension L12 of the section closest to the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X, and has the same beneficial effects as the above-mentioned embodiments, which are not elaborated here one by one.

[0125] For example, refer to Figure 10C to Figure 10F, the shape of the positive projection of the groove 61 on the second surface 1b is a trapezoid or a semi-ellipse, which can ensure that the size L11 of the section farthest from the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X is smaller than the size L12 of the section closest to the first selected side surface 1cc among the multiple cross-sections of the groove 61 in the first direction X, and, along the direction from the first selected side surface 1cc to the second selected side surface 6cc, the size of the groove 61 in the first direction gradually narrows, so that in the process of the printing needle P moving relatively to print the conductive paste, in the groove 61, the accumulation speed of the conductive paste gradually increases, and the height of the conductive paste accumulation gradually increases, which is equivalent to forming a gentle slope, reducing the difficulty of printing, making the formed third part more reliable, and having the same beneficial effects as the above-mentioned embodiments, which are not repeated here.

[0126] In some embodiments, reference Fig.11A and Fig. 11B A buffer structure 7 is disposed at the side wall of the groove 61 close to the back electrode 4 , the second portion 332 is located in the groove 61 and a portion of the second portion 332 is located on the buffer structure 7 .

[0127] It should be noted that the thickness of the buffer structure 7 near the side wall of the back electrode 4 in the third direction Z is less than or equal to the thickness of the groove 61 in the third direction Z, so as to ensure that the second part 332 of the connecting line 3 can be printed while climbing slowly, reducing the difficulty of climbing.

[0128] For example, refer to Fig. 10A The thickness of the portion of the side wall of the buffer structure 7 close to the back electrode 4 in the third direction Z is less than the thickness of the groove 61 in the third direction Z. The buffer structure 7 is located in the groove 61, and the buffer structure 7 is close to one side of the back electrode 4. The buffer structure 7 is provided, which is equivalent to constructing a gentle slope inside the groove 61 before printing the second portion 332 of the connecting wiring 3, which to a certain extent decomposes the height difference between the second surface 1b and the fourth surface 6b. The second portion 332 in the groove 61 can achieve slow climbing through the buffer structure 7, thereby avoiding the problem of breakage due to the large height difference during the curing process of the conductive paste.

[0129] For example, refer to Fig. 10B, the thickness of the portion of the side wall of the buffer structure 7 close to the back electrode 4 in the third direction Z is equal to the thickness of the groove 61 in the third direction Z, that is, the thickness of the portion of the side wall of the buffer structure 7 close to the back electrode 4 in the third direction Z is equal to the thickness of the bridging structure 6 in the third direction Z, and in the process of printing the second part 332 of the connecting wiring 3, the conductive paste can be evenly printed along the side of the buffer structure 7 away from the substrate 1, and in the process of continuing to print the third part 333, since there is no height difference between the second part 332 and the third part 333, the printing device can maintain a smooth transition printing at a height, and at the same time, it can avoid the connection wiring 3 formed due to the height difference. The phenomenon of breakage is finally caused.

[0130] In some embodiments, the material of the buffer structure 7 includes an organic material.

[0131] Exemplarily, the material of the buffer structure 7 may be resin or polyimide.

[0132] In some embodiments, reference Fig.12 The groove 61 and the corresponding back electrode 4 have a first spacing H1 in the second direction Y; the ratio of the size H2 of the groove 61 in the second direction Y to the first spacing H1 is in the range of 0.6-1.

[0133] For example, Fig.12 As shown, the groove 61 and the corresponding back electrode 4 are arranged to have a first spacing H1 in the second direction Y, that is, referring to Fig. 9 , a certain height difference is formed between the fourth surface 6b of the bridging structure 6 and the side of the back electrode 4 away from the bridging structure 6, which is equivalent to a buffer step. The main purpose is to ensure that in the process of printing the second part 332 of the connecting line 3, the height difference is only the thickness of the bridging structure 6 in the third direction Z; if the groove 61 and the corresponding back electrode 4 have no spacing in the second direction Y, that is, the side of the back electrode 4 close to the second selected side surface 6cc coincides with the side of the groove 61 away from the second selected side surface 6cc, in the process of printing the second part 332 of the connecting line 3, the height difference becomes the sum of the thickness of the bridging structure 6 in the third direction Z and the thickness of the back electrode 4 in the third direction Z. The greater the height difference, the more unfavorable it is for printing the connecting line 3, and the part where the second part 332 and the third part 333 of the connecting line 3 are connected is more likely to break. Therefore, the groove 61 and the corresponding back electrode 4 are provided with a first spacing H1 in the second direction Y to avoid the above problems.

[0134] It is understandable that by setting the ratio range of the dimension H2 of the groove 61 in the second direction Y to the first spacing H1, it is possible to ensure that the uniformity of the conductive paste leveling is improved when the connection trace 3 is prepared by the printing process, and the formed connection trace 3 is more reliable, while reducing the difficulty of printing and the conductive paste is evenly distributed. Exemplarily, the ratio of the dimension H2 of the groove 61 in the second direction Y to the first spacing H1 can be 0.6, 0.8, or 1.

[0135] In some embodiments, reference Fig.13 , a second distance H3 is formed between the side of the bridging structure 6 close to the first selected side surface 1 cc and the first selected side surface 1 cc in the second direction Y.

[0136] It can be understood that the side of the bridging structure 6 close to the first selected side surface 1cc is provided with a second spacing H3 with the first selected side surface 1cc in the second direction Y. On the one hand, a step can be formed between the substrate 1 and the bridging structure 6. Compared with the design in which the boundary of the bridging structure 6 close to the first selected side surface 1cc overlaps or roughly overlaps with the first selected side surface 1cc, while reserving the setting space of the buffer structure 7, the length of the portion of the connecting line 3 located between the bridging structure 6 and the first selected side surface 1cc is extended. When the third line 33 of the connecting line 3 is prepared by the printing process, the conductive paste can slowly climb the slope, which reduces the printing difficulty and makes the conductive paste more evenly distributed. On the other hand, the connection firmness between the bridging structure 6 and the substrate 1 can be increased to prevent the bridging structure 6 from moving in the subsequent process of the display panel 10 and affecting the position accuracy of the back electrode 4. At the same time, compared with the design in which the boundary of the bridging structure 6 close to the first selected side surface 1cc overlaps or roughly overlaps with the first selected side surface 1cc, the boundary of the bridging structure 6 close to the first selected side surface 1cc can be prevented from warping and other undesirable phenomena.

[0137] The above embodiments are all cases where the bridge structure 6 is provided with a groove 61 . The following describes some embodiments where the bridge structure 6 is not provided with a groove 61 .

[0138] In some embodiments, reference Fig.14A and Fig. 14B The buffer structure 7 is arranged on the side of the bridge structure 6 close to the first selected side surface 1cc, the connecting wire 3 crosses the buffer structure 7 and is connected to the back electrode, and the buffer structure 7 is spaced apart from the first selected side surface 1cc.

[0139] It can be understood that by setting the buffer structure 7, on the one hand, the adhesion tightness between the portion of the bridging structure 6 close to the selected side 11cc and the substrate 1 is increased, thereby preventing the back electrode 4 from deviating from the set position due to the displacement of the bridging structure 6, thereby ensuring that the connecting line 3 and the back electrode 4 can be effectively connected, and then ensuring that the driving signal can be transmitted to the light-emitting device through the connecting line 3, ensuring that the display panel 10 can display normally; on the other hand, due to the setting of the buffer structure 7, the buffer structure forms a step, which to a certain extent decomposes the height difference between the second surface 1b and the fourth surface 6b, and the conductive paste can pass through the buffer structure 7 to achieve slow climbing, reducing the difficulty of printing, and can relatively easily control the distance between the printing needle P and the buffer structure, and improve the smoothness and uniformity of the conductive paste, so that the width and thickness of the connecting line can be better controlled, avoiding the problem of breakage due to large height difference during the curing process of the conductive paste.

[0140] In some examples, such as Fig.14A As shown, the thickness of the portion of the buffer structure 7 at the side wall close to the back electrode 4 in the third direction Z is equal to the thickness of the groove 61 in the third direction Z, that is, the thickness of the portion of the buffer structure 7 at the side wall close to the back electrode 4 in the third direction Z is equal to the thickness of the bridging structure 6 in the third direction Z. In the process of printing and forming the second part 332 of the connecting wiring 3, due to the setting of the buffer structure 7, the side of the buffer structure 7 away from the second surface 1b is an arc surface with a certain slope, that is, the height difference between the fourth surface 6b of the bridging structure 6 and the second surface 1b of the substrate 1 becomes an overall gentle slope, and the conductive paste can be evenly printed along the side of the buffer structure 7 away from the substrate 1. In the process of continuing to print the third part 333, since there is no height difference between the second part 332 and the third part 333, the printing device can maintain a smooth transition printing at a height, and at the same time, it can avoid the connection wiring 3 formed due to the height difference. The phenomenon of breakage is finally caused.

[0141] In other examples, such as Fig. 14B As shown, the buffer structure 7 is arranged on the second selected side surface of the bridge structure, and the buffer structure 7 is also arranged on the fourth surface of the bridge structure, wrapping the boundary edge between the second selected side surface and the fourth surface of the bridge structure 6, so that the conductive paste can reach the fourth surface 6b from the surface of the buffer structure, and connect with the back electrode 4, to achieve a smooth transition, and reduce the risk of fracture caused by the conductive paste being subjected to a large force at the boundary edge between the second selected side surface and the fourth surface of the bridge structure. Further, the buffer structure 7 is arranged on the fourth surface of the bridge structure 6, and is also overlapped on multiple back electrodes 4, and the surface of the buffer structure 7 is a gently sloping surface, so that the formed conductive paste is more easily overlapped with the back electrode 4 along the gentle slope surface of the buffer structure 7 due to its fluidity, further improving the preparation efficiency.

[0142] The embodiment of the present disclosure further provides a display device 100. Fig.15 and Figure 1 As shown, the display device 100 includes a display panel 10 and a driving circuit board 20 provided in any of the foregoing embodiments. The driving circuit board 20 is electrically connected to the display panel 10; for example, the driving circuit board 20 is electrically connected to the back electrode 4 of the display panel 10 through the flexible circuit board 8, and the electrical signal provided by the driving circuit board 20 is transmitted to the driving circuit layer of the display panel 10 via the flexible circuit board 8, the back electrode 4, the connecting wire 3 and the front electrode 2 to control the light-emitting device to emit light. The driving circuit board 20 is configured to send a driving signal to the display panel 10, thereby driving the display panel 10 to display an image.

[0143] In other embodiments, referring to Fig.16 The driving circuit board 20 is directly connected to the back electrode 4 of the display panel 10. The electrical signal provided by the driving circuit board 20 is transmitted to the driving circuit layer of the display panel 10 via the back electrode 4, the connecting line 3 and the front electrode 2 to control the light-emitting device to emit light.

[0144] In the display device 100, Mini LED or Micro LED is used as the light-emitting device, which has a smaller volume. On a substrate of the same area, the arrangement density of the light-emitting devices 51 per unit area can be higher. In addition, the light-emitting devices 51 can be driven independently or in partitions, thereby improving the uniformity of the display brightness and further improving the display quality of the display device 100.

[0145] The display device 100 may be any device that displays, whether in motion (e.g., video), stationary (e.g., still images), text, or images. 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., odometer displays, etc.), navigators, cockpit controls and / or displays, displays of camera views (e.g., displays of rear-view 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), etc.

[0146] Exemplarily, the display device 100 may further include a frame and other electronic components, etc. The display panel 10 may be disposed in the frame, for example.

[0147] The display device 100 has the same structure and beneficial technical effects as the display panel 10 provided in some of the above embodiments, which will not be described in detail herein.

[0148] The embodiment of the present disclosure further provides a spliced ​​display device 200 .

[0149] In some embodiments, Fig.17 As shown, the spliced ​​display device 200 includes: a plurality of spliced ​​display panels 10 as described in any of the above embodiments.

[0150] In other embodiments, Fig.19 As shown, the spliced ​​display device 200 includes: a plurality of spliced ​​display devices 100 as described in the above embodiments.

[0151] The following description will be made by taking an example where the spliced ​​display device 200 includes a plurality of spliced ​​display devices 100 .

[0152] For example, Fig.17 and Fig.19 As shown, the display device 100 is, for example, rectangular.

[0153] In some examples, such as Fig.17 As shown, the multiple display panels 10 in the spliced ​​display device 200 are arranged in an array.

[0154] like Figure 1 As shown, in the display panel 10, a plurality of front electrodes 2 are arranged in parallel along a first direction X, and correspondingly, a plurality of connection traces 3 are also arranged in parallel along the first direction X, and another direction parallel to the first surface 1a of the display panel 10 and perpendicular to the first direction X is referred to as a second direction Y. The display device 100 includes a plurality of side surfaces, and hereinafter, the side surfaces of the plurality of side surfaces of the display device 100 close to the plurality of front electrodes 2 are referred to as selected side surfaces of the display device 100 for description.

[0155] For example, Figure 2 As shown, 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 multiple upper electrodes 2, and the two groups of front electrodes 2 are respectively arranged close to the two binding areas BB.

[0156] Furthermore, if Fig.17 As shown, multiple Figure 2When the display devices 100 of the display panel 10 shown are spliced, for example, the selected side surfaces of two adjacent display devices 100 are arranged along the first direction X. In this way, among the multiple display devices 100 arranged in a row along the first direction X, there is basically no splicing seam between two adjacent display devices 100 along the first direction X; there is a splicing gap between two adjacent display devices 100 among the multiple display devices 100 arranged in a row along the second direction Y, that is, the size of the splicing gap between two adjacent display devices 100 among the multiple display devices 100 arranged in a row along the first direction X is smaller than the size of the splicing gap between two adjacent display devices 100 among the multiple display devices 100 arranged in a row along the second direction Y.

[0157] However, the size of the binding area BB in the second direction Y is very small, so when the spliced ​​display device 200 is actually viewed, the seam between two adjacent display devices 100 is difficult to be seen by the naked eye within the viewing distance, so that the display screen of the spliced ​​display device 200 is more complete and can present a better display effect.

[0158] For example, Fig.18 As shown, the display panel 10 includes a display area AA and a binding area BB located at one side of the display area AA, and a plurality of front electrodes 2 are disposed in the binding area BB.

[0159] Furthermore, if Fig.19 As shown, multiple include Fig.18 When the display devices 100 of the display panel 10 shown are spliced, the selected side surfaces of two adjacent display devices 100 are arranged along the first direction X, so that among the multiple display devices 100 arranged in a row along the first direction X, there is basically no splicing seam between two adjacent display devices 100 along the first direction X; there is a splicing gap between two adjacent display devices 100 among the multiple display devices 100 arranged in a row along the second direction Y, that is, the size of the splicing gap between two adjacent display devices 100 among the multiple display devices 100 arranged in a row along the first direction X is smaller than the size of the splicing gap between two adjacent display devices 100 among the multiple display devices 100 arranged in a row along the second direction Y.

[0160] However, the size of the binding area BB in the second direction Y is very small, so when the spliced ​​display device 200 is actually viewed, the seam between two adjacent display devices 100 is difficult to be seen by the naked eye within the viewing distance, so that the display screen of the spliced ​​display device 200 is more complete and can present a better display effect.

[0161] The spliced ​​display device 200 has the same structure and beneficial technical effects as the display device 100 provided in some of the above embodiments, which will not be described in detail herein.

[0162] In another aspect, a method for manufacturing a display panel 10 is provided. Figures 20A to 20E As shown, the method for preparing the display panel 10 includes:

[0163] R1: Provide initial substrate.

[0164] R2: forming a front film layer structure on the front side of the initial substrate.

[0165] Exemplarily, the front film layer structure includes a driving circuit layer.

[0166] R3: A plurality of front electrodes 2 arranged in parallel and at intervals are formed on the front surface of the initial substrate.

[0167] R4: cutting the initial substrate to form a plurality of substrates 1; Fig. 20A As shown, the substrate 1 includes a first surface 1a and a second surface 1b that are oppositely disposed, 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.

[0168] The front electrode 2 and the film structure such as the driving circuit layer are all arranged on the front side of the substrate 1. The front electrode 2 is close to the selected first side surface 1cc.

[0169] R5: Disposing the bridge structure 6 on the second surface 1 b of the substrate 1 .

[0170] Reference Fig.20D The bridge structure 6 includes a third surface 6a and a fourth surface 6b that are arranged opposite to each other, and a plurality of second side surfaces 6c that connect the third surface 6a and the fourth surface 6b; the third surface 6a is closer to the substrate 1 relative to the fourth surface 6b; the plurality of second side surfaces 6c include at least one second selected side surface 6cc; each second selected side surface 6cc corresponds to a first selected side surface 1cc. A plurality of grooves 61 are provided in the portion of the bridge structure 6 that is close to the first selected side surface, and the openings of the plurality of grooves 61 face the first selected side surface 1cc. Exemplarily, an etching process is used to form a plurality of grooves 61 in the bridge structure.

[0171] The process of connecting the bridge structure 6 to the second surface 1 b of the substrate 1 is, for example, high-precision bonding.

[0172] Before R5, refer to Fig. 20B and Fig. 20C A plurality of back electrodes 4 are formed on the fourth surface 6b of the bridge structure 6. The plurality of back electrodes 4 are close to the second selected side surface 6cc, and each of the plurality of grooves 61 corresponds to a back electrode 4. Exemplarily, the plurality of back electrodes 4 are formed by a wet etching process.

[0173] R6: Reference Fig.20E , forming a plurality of connecting wires 3 arranged in parallel and at intervals; each of the plurality of connecting wires 3 includes a first wire 31 located on one side of the first surface 1a, a second wire 32 located on one side of the first selected side surface 1cc, and a third wire 33 located on one side of the second surface 1b; the third wire 33 includes a first portion 331, a second portion 332, and a third portion 333 connected in sequence; the second portion 332 is located in the groove 61, the third portion 333 is located on one side of the fourth surface 6b, and is connected to the back electrode 4, and the first portion 331 is located between the second portion 332 and the second wire 32.

[0174] Exemplarily, the process for forming the plurality of connection traces 3 is a printing process, such as three-dimensional printing.

[0175] In some embodiments, the method for preparing the display panel 10 further includes, before step R6:

[0176] R5-1: Reference Fig.11A and Fig. 11B , a buffer structure 7 is formed in the groove 61 of the bridging structure 6 .

[0177] In some other embodiments, when the bridging structure is not provided with the groove 61, before step R6, the following steps are included:

[0178] R5-1: Reference Fig.14A and Fig. 14B , a buffer structure 7 is formed on the side surface of the bridge structure 6 close to the selected second side surface 1cc.

[0179] For example, Fig. 14B The buffer structure 7 disposed in the middle is flush with the back electrode 4 on one side close to the back electrode 4 , and the specific effect is referred to the introduction in the above part.

[0180] For example, Fig. 14B The buffer structure 7 arranged in the middle overlaps with the back electrode 4 near the side of the back electrode 4, which can achieve uniform transition printing of the printing device and avoid the breakage of the connection wiring formed due to height difference.

[0181] The process for forming the buffer structure 7 is, for example, three-dimensional printing.

[0182] The above-mentioned preparation processes, such as printing processes, are only described as examples and are not intended to limit the actual production process.

[0183] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be thought of by any person skilled in the art within the technical scope disclosed in the present disclosure should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

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

2. The display panel according to claim 1, characterized in that: A dimension of the second portion along a first direction is smaller than dimensions of the first portion and the third portion along the first direction, and the first direction is perpendicular to an extending direction of the third trace.

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

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

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

6. The display panel according to claim 1, characterized in that: The dimension of the groove in the first direction is smaller than the dimension of the back electrode in the first direction, and the first direction is perpendicular to the extending direction of the third wiring.

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

6.

8. The display panel according to claim 1, characterized in that: On a plane parallel to and perpendicular to the second direction, the groove has multiple cross-sections, and the cross-section farthest from the first selected side surface among the multiple cross-sections has a size in the first direction that is smaller than or equal to the size of the cross-section closest to the first selected side surface among the multiple cross-sections in the first direction, and the first direction is perpendicular to the extension direction of the third routing line.

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

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

11. The display panel according to claim 1, characterized in that: The groove and the corresponding back electrode have a first distance in a second direction, and the second direction is an extending direction of the third wiring; The ratio of the size of the groove in the second direction to the first spacing is in a range of 0.6-1.

12. The display panel according to claim 1 or 11, characterized in that: A side of the bridging structure close to the first selected side surface has a second distance from the first selected side surface in a second direction, and the second direction is an extending direction of the third trace.

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

14. A splicing display device, characterized in that: A display device comprising a plurality of display devices as claimed in claim 13 connected together; or a display panel comprising a plurality of display panels as claimed in any one of claims 1 to 12 connected together.

Images