Light-emitting substrate and display device

Abstract

Provided is a light-emitting substrate. The light-emitting substrate comprises: a base substrate, comprising a light-emitting region; a plurality of light-emitting elements located on the base substrate, the plurality of light-emitting elements being located in the light-emitting region; and a plurality of first common signal lines and a plurality of second common signal lines that are located on the base substrate and electrically connected to the plurality of light-emitting elements, wherein each first common signal line among the plurality of first common signal lines comprises a first main body extending in a first direction, each second common signal line among the plurality of second common signal lines comprises a second main body extending in the first direction, the first direction extends from a first edge of the base substrate toward a second edge opposite to the first edge, the light-emitting substrate further comprises a first conductive structure and a second conductive structure that are located on the base substrate, the first conductive structure electrically connects at least some first common signal lines among the plurality of first common signal lines to each other, the second conductive structure electrically connects at least some second common signal lines among the plurality of second common signal lines to each other, the first conductive structure and the second conductive structure extend in a second direction intersecting the first direction, and the first conductive structure and the second conductive structure are located in the light-emitting region.

Description

Light-emitting substrate and display device Technical Field

[0001] This application relates to the field of display technology, and more specifically, to a light-emitting substrate and a display device including the light-emitting substrate. Background Technology

[0002] In the field of display technology, semiconductor light-emitting devices (e.g., light-emitting diodes) have been adopted as backlight sources. Using small-sized (sub-millimeter or even micrometer-scale) light-emitting diodes as backlight sources is more conducive to fine-tuning of the backlight, enabling local dimming within a smaller area, thereby achieving better brightness uniformity. However, existing light-emitting substrates and display devices still face the problem of high cost, while the bezels of display products are also expected to be narrower.

[0003] Summary of the Invention

[0004] This application provides a light-emitting substrate to reduce the cost of the light-emitting substrate and the display device using the light-emitting substrate, and to promote the narrowing of the bezel of the display device.

[0005] This application provides a light-emitting substrate comprising: a substrate including a light-emitting region; a plurality of light-emitting elements located on the substrate within the light-emitting region; and a plurality of first common signal lines and a plurality of second common signal lines located on the substrate and electrically connected to the plurality of light-emitting elements. Each of the plurality of first common signal lines includes a first body extending along a first direction, and each of the plurality of second common signal lines includes a second body extending along the first direction. The first direction extends from a first edge of the substrate to a second edge directly opposite the first edge. The light-emitting substrate further includes a first conductive structure and a second conductive structure located on the substrate. The first conductive structure electrically connects at least a portion of the plurality of first common signal lines to each other, and the second conductive structure electrically connects at least a portion of the plurality of second common signal lines to each other. The first conductive structure and the second conductive structure extend along a second direction intersecting the first direction, and the first conductive structure and the second conductive structure are located within the light-emitting region.

[0006] According to some embodiments of this application, the light-emitting area includes an array of light-emitting units, each light-emitting unit in the array of light-emitting units includes K light-emitting elements from the plurality of light-emitting elements, wherein the orthographic projections of the first conductive structure and the second conductive structure on the substrate do not overlap with the orthographic projections of the light-emitting elements in each light-emitting unit on the substrate, wherein K is greater than or equal to 2.

[0007] According to some embodiments of this application, at least one of the first conductive structure and the second conductive structure is located in the gap between light-emitting units in different rows of the light-emitting unit array.

[0008] According to some embodiments of this application, at least one of the first conductive structure and the second conductive structure is located within the gap between different light-emitting elements of the same light-emitting unit in the light-emitting unit array.

[0009] According to some embodiments of this application, the first common signal line includes a power line for transmitting power supply voltage to each light-emitting unit in the light-emitting unit array, and the second common signal line includes a reference ground potential line.

[0010] According to some embodiments of this application, the light-emitting substrate further includes a protective layer located on the first common signal line and the second common signal line. The first conductive structure and the second conductive structure are located on the side of the protective layer away from the substrate. The protective layer includes a plurality of first conductive vias corresponding to at least a portion of the first common signal lines and a plurality of second conductive vias corresponding to at least a portion of the second common signal lines. The first conductive structure is electrically connected to the at least a portion of the first common signal lines via the plurality of first conductive vias, and the second conductive structure is electrically connected to the at least a portion of the second common signal lines via the plurality of second conductive vias.

[0011] According to some embodiments of this application, each of the first conductive structure and the second conductive structure comprises a material different from the first common signal line and the second common signal line.

[0012] According to some embodiments of this application, each of the first conductive structure and the second conductive structure includes silver paste, and the first common signal line and the second common signal line include copper.

[0013] According to some embodiments of this application, the light-emitting substrate further includes a light-reflecting layer located on the substrate, the light-reflecting layer covering the first conductive structure and the second conductive structure.

[0014] According to some embodiments of this application, the light-emitting substrate further includes a light-reflecting layer, which covers the protective layer and is located between the first conductive structure or the second conductive structure and the protective layer. The light-reflecting layer includes a third conductive via communicating with the first conductive via or the second conductive via.

[0015] According to some embodiments of this application, the light-emitting substrate further includes light-emitting element interconnecting lines that connect the K light-emitting elements in the light-emitting unit in series. The light-emitting element interconnecting lines are located on the side of the protective layer away from the substrate and are in the same layer as the first conductive structure and the second conductive structure.

[0016] According to some embodiments of this application, each of the first conductive structure and the second conductive structure includes a zero-ohm resistance jumper.

[0017] According to some embodiments of this application, the substrate further includes a bonding region located outside the light-emitting region, wherein one of the first conductive structure and the second conductive structure is located in the gap between the two rows of light-emitting units closest to the bonding region in the light-emitting unit array.

[0018] According to some embodiments of this application, the first conductive structure and the second conductive structure are located in the gap between different light-emitting elements in the row of light-emitting units closest to the bonding area in the light-emitting unit array.

[0019] According to some embodiments of this application, the light-emitting substrate further includes a driving circuit array located on the substrate, each driving circuit in the driving circuit array being electrically connected to at least one light-emitting unit in the light-emitting unit array, wherein each row of driving circuits in the driving circuit array is located in the gap between light-emitting units in different rows of the light-emitting unit array, and each row of driving circuits is spaced apart from the first conductive structure or the second conductive structure by at least one row of light-emitting units in the first direction.

[0020] According to some embodiments of this application, the light-emitting substrate further includes driving circuit signal lines connected to the driving circuit, and the substrate further includes a fan-out region located between the light-emitting region and the bonding region. The driving circuit signal lines extend from the light-emitting region through the fan-out region to the bonding region. At least a portion of the first common signal lines include multiple first-length power lines and at least one second-length power line. The second-length power line extends from the light-emitting region through the fan-out region to the bonding region. The first-length power lines extend within the light-emitting region, and their orthogonal projection on the substrate does not overlap with the fan-out region and the bonding region. At least a portion of the second common signal lines include multiple first-length reference ground potential lines and at least one second-length reference ground potential line. The second-length reference ground potential line extends from the light-emitting region through the fan-out region to the bonding region. The first-length reference ground potential line extends within the light-emitting region, and its orthogonal projection on the substrate does not overlap with the fan-out region and the bonding region. According to some embodiments of this application, the plurality of first-length power lines are distributed along the second direction on both sides of the at least one second-length power line, and the plurality of first-length reference ground potential lines are distributed along the second direction on both sides of the at least one second-length reference ground potential line.

[0021] According to some embodiments of this application, the width of the first end of the at least one second-length power line near the bonding area is greater than the width of the first body of the second-length power line, and the width of the first end of the at least one second-length reference ground potential line near the bonding area is greater than the width of the second body of the second-length reference ground potential line.

[0022] According to some embodiments of this application, the K light-emitting elements in the light-emitting unit are connected in series to form a first light-emitting unit pattern, wherein the light-emitting substrate further includes an additional light-emitting unit row in the fan-out region, each additional light-emitting unit in the additional light-emitting unit row includes a plurality of additional light-emitting elements, the plurality of additional light-emitting elements are connected in series to form a second light-emitting unit pattern, wherein a portion of the first light-emitting unit pattern of the light-emitting unit in the bottom light-emitting unit row closest to the bonding region in the light-emitting unit array is symmetrical with respect to a portion of the second light-emitting single-unit pattern of the additional light-emitting unit in the additional light-emitting unit row about the gap extending along the second direction between the bottom light-emitting unit row and the additional light-emitting unit row.

[0023] According to some embodiments of this application, at least one of the first conductive structure and the second conductive structure includes a plurality of sub-conductive structures. Each of the plurality of sub-conductive structures is located in the gap between light-emitting units in different rows of the light-emitting unit array. The plurality of sub-conductive structures are electrically connected to each other via the at least a portion of the first common signal line or the at least a portion of the second common signal line. The bottom sub-conductive structure closest to the bonding region among the plurality of sub-conductive structures includes a zero-ohm jumper. The other sub-conductive structures among the plurality of sub-conductive structures, except for the bottom sub-conductive structure, are formed of the same material as the first common signal line and the second common signal line.

[0024] According to some embodiments of this application, the bottom sub-conductive structure further includes an additional conductive structure connected in parallel with the zero-ohm resistance jumper, the additional conductive structure being formed of the same material as the first common signal line and the second common signal line.

[0025] According to some embodiments of this application, the plurality of first common signal lines and the plurality of second common signal lines are arranged alternately in the second direction. The first common signal line further includes a first protrusion extending from the first body toward the adjacent second common signal line along the second direction. The adjacent second common signal line further includes a second protrusion extending from the second body toward the first common signal line along a third direction, which is opposite to the second direction.

[0026] According to some embodiments of this application, the first common signal line and the adjacent second common signal line are located between two adjacent columns of light-emitting units in the light-emitting unit array, wherein one of the first protrusion and the second protrusion is located within the region of a single light-emitting unit in the light-emitting unit array, and the other of the first protrusion and the second protrusion is located between two adjacent rows of light-emitting units in the light-emitting unit array.

[0027] According to some embodiments of this application, the first common signal line further includes a third protrusion extending from the first body toward an adjacent second common signal line along the third direction, wherein the first protrusion of the first common signal line in at least a portion of the first common signal lines is electrically connected to the third protrusion of the adjacent first common signal line via the first conductive structure.

[0028] According to some embodiments of this application, each of the first protrusion and the second protrusion is located in the gap between light-emitting units in adjacent rows of the light-emitting unit array, wherein the first protrusion of the first common signal line in at least a portion of the first common signal lines is electrically connected to the first body of the adjacent first common signal line via the first conductive structure, and the second protrusion of the second common signal line in at least a portion of the second common signal lines is electrically connected to the second body of the adjacent second common signal line via the second conductive structure.

[0029] According to some embodiments of this application, the plurality of first common signal lines and the plurality of second common signal lines are arranged alternately in the second direction. The first common signal line further includes a first protrusion extending from the first body toward the adjacent second common signal line along the second direction. The first protrusion includes a hollow portion. The light-emitting substrate further includes a conductive block located in the hollow portion and isolated from the first protrusion. The conductive block is electrically connected to two adjacent second common signal lines in the at least a portion of the second common signal lines via the second conductive structure. The first protrusion of the first common signal line in the at least a portion of the first common signal lines is electrically connected to the first body of the adjacent first common signal line via the first conductive structure.

[0030] Another embodiment of this application provides a display device, which includes a light-emitting substrate according to any of the foregoing embodiments.

[0031] The embodiments of the light-emitting substrate and display device provided in this application have been summarized above. Other embodiments of this application include additional embodiments formed by combining different embodiments of the above-described embodiments or combining different technical features of the embodiments. The technical features and corresponding technical advantages of the above-described embodiments can be more clearly understood through the detailed description of the embodiments below in conjunction with the accompanying drawings. Attached Figure Description

[0032] Embodiments of this application will now be described in more detail with reference to the accompanying drawings, wherein:

[0033] Figure 1 schematically illustrates an example of signal lines for four rows of light-emitting units converging into a bonding area;

[0034] Figure 2 schematically shows the arrangement of light-emitting elements on a light-emitting substrate comprising 36*64 light-emitting units;

[0035] Figure 3 illustrates an example of a partial plan view of a light-emitting substrate provided according to an embodiment of this application;

[0036] Figure 4 illustrates an example of a partial plan view of a light-emitting substrate provided according to another embodiment of this application;

[0037] Figure 5 illustrates an example of a partial plan view of a light-emitting substrate provided according to yet another embodiment of this application;

[0038] Figure 6 illustrates a partial plan view of a light-emitting substrate provided according to yet another embodiment of this application;

[0039] Figure 7 is a partial enlarged view of the light-emitting substrate shown in Figure 6;

[0040] Figures 8 to 12 illustrate partial cross-sectional views of light-emitting substrates provided according to different embodiments;

[0041] Figure 13 is a partial cross-sectional view of a light-emitting substrate according to an embodiment of the present application along the dashed line B1-B2 shown in Figure 4;

[0042] Figure 14 illustrates a partial cross-sectional view of the light-emitting substrate provided according to this embodiment;

[0043] Figure 15 illustrates a partially enlarged schematic diagram of the boundary between the fan-out region and the light-emitting region of a light-emitting substrate according to an embodiment of the present application.

[0044] Figure 16 illustrates the electrical connection between multiple first common signal lines and a first conductive structure, and the electrical connection between multiple second common signal lines and a second conductive structure of a light-emitting substrate provided according to an embodiment of this application.

[0045] Figure 17 illustrates a partially enlarged schematic diagram of some first common signal lines and second common signal lines on a light-emitting substrate provided according to some embodiments of this application;

[0046] Figure 18 illustrates a partially enlarged schematic diagram of some first common signal lines and second common signal lines on a light-emitting substrate according to another embodiment of this application;

[0047] Figure 19 illustrates a partially enlarged schematic diagram of some first common signal lines and second common signal lines on a light-emitting substrate according to another embodiment of the present application. Detailed Implementation

[0048] The following description provides specific details of various embodiments of this application to enable those skilled in the art to fully understand and implement the various embodiments of this application. In some cases, this application does not show or describe in detail some structures or functions well known in the art to avoid such unnecessary descriptions that would obscure the description of the embodiments of this application. The technical solutions of this application can be embodied in many different forms and for many different purposes, and should not be limited to the embodiments set forth herein. These embodiments are provided to make the technical solutions of this application clear and complete, but the embodiments do not limit the scope of protection of this patent application.

[0049] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the technical solutions of this application can be practiced without one or more of these details. Detailed steps and structures are set forth in the following description to illustrate the technical solutions proposed by the present invention. The terminology used in this application should be understood in its broadest reasonable sense, even when used in connection with specific embodiments of this application.

[0050] As a backlight source for a display device, the light-emitting substrate typically has multiple bonding areas. The light-emitting elements and corresponding driving circuits on the substrate are electrically connected to external circuits through these bonding areas to provide a common voltage and control signals for controlling the individual light-emitting elements. The inventors of this application recognized that a significant factor contributing to the high cost of the light-emitting substrate and the display device including it is the number of bonding areas. To reduce the number of bonding areas, signal lines involving multiple light-emitting units within the light-emitting area of ​​the substrate can be converged to a single bonding area. For example, FIG1 schematically illustrates an example where signal lines for four columns of light-emitting units are converged to a single bonding area B. The light-emitting substrate also includes multiple driving circuit ICs for driving one or more light-emitting units to emit light. In FIG1, each light-emitting unit includes four light-emitting diodes (e.g., mini-LEDs). The signal lines for each column of light-emitting units include a power supply line VLED transmitting the operating voltage to each light-emitting diode, a reference ground potential line GND, and a driving signal line DL connected to the driving circuit IC, etc. The signal lines for the four columns of light-emitting units converge to a single bonding area B in the peripheral region of the light-emitting substrate. However, in practice, the number of light-emitting elements contained in the light-emitting substrate is very large. The light-emitting area of ​​the substrate may include far more than four columns of light-emitting units. It may be impractical to converge all the signal lines involved in the light-emitting units into a single bonding area as shown in Figure 1, because the bezel size of the display device limits this approach. Actual display devices may include hundreds or even thousands of light-emitting areas. Figure 2 schematically shows a schematic diagram of the arrangement of light-emitting elements on a light-emitting substrate including 36*64 light-emitting units. That is, the light-emitting substrate includes 64 columns of light-emitting units, and each column includes 36 light-emitting units. The smaller gray dots in Figure 2 represent light-emitting elements, and multiple light-emitting elements form a light-emitting unit. The larger gray dots represent the driving circuits used to drive the individual light-emitting elements in the light-emitting unit. To reduce the overall number of bonding areas on the light-emitting substrate, in the example of Figure 2, the signal lines of every 8 columns of light-emitting units converge into one bonding area. Accordingly, the light-emitting substrate includes 8 bonding areas, namely bonding areas b1, b2, b3, b4, b5, b6, b7, and b8. The horizontal axis of Figure 2 indicates the number of each bonding area, and the vertical axis indicates the row number of some light-emitting units. Referring back to Figure 1, the signal lines for each column of light-emitting units include the power supply line VLED, the reference ground potential line GND, and the drive signal line DL connected to the driver circuit IC. The power supply line VLED and the reference ground potential line GND apply voltage to the two electrodes of the light-emitting element to make the light-emitting element emit light. The power supply line VLED and the reference ground potential line GND usually carry a large current, and at the same time, their own resistance needs to be minimized to reduce the loss of the wires. Therefore, the width of the power supply line VLED and the reference ground potential line GND is wider than that of other signal lines.If the signal lines for all the light-emitting units were converged to a single bonding area, the bottom bezel of the display device would inevitably be too large, which is inconsistent with current user expectations or aspirations for display products. Therefore, in the example of Figure 2, eight bonding areas are provided on the light-emitting substrate. Accordingly, the display device requires eight flexible printed circuit boards (FPCs) or chip-on-film (COF) to be connected to the eight bonding areas respectively, in order to electrically connect the light-emitting substrate to an external control circuit board (e.g., a printed circuit board PCB).

[0051] The large number of bonding areas and the corresponding flexible printed circuit boards (FPCs) or chip-on-film (COF) films are significant factors contributing to the high cost of light-emitting substrates. The light-emitting substrates provided in the embodiments described below aim to reduce the number of bonding areas on the light-emitting substrate while avoiding excessively large sizes of the light-emitting substrate and the bezel area of ​​the display device including the light-emitting substrate. The light-emitting substrate provided according to an embodiment of this application includes: a substrate, the substrate including a light-emitting region; a plurality of light-emitting elements located on the substrate, the plurality of light-emitting elements being located within the light-emitting region; and a plurality of first common signal lines and a plurality of second common signal lines located on the substrate and electrically connected to the plurality of light-emitting elements. Each of the plurality of first common signal lines includes a first body extending along a first direction, and each of the plurality of second common signal lines includes a second body extending along the first direction. The first direction extends from a first edge of the substrate to a second edge directly opposite the first edge. The light-emitting substrate further includes a first conductive structure and a second conductive structure located on the substrate. The first conductive structure electrically connects at least a portion of the plurality of first common signal lines to each other, and the second conductive structure electrically connects at least a portion of the plurality of second common signal lines to each other. The first conductive structure and the second conductive structure extend along a second direction intersecting the first direction, and the first conductive structure and the second conductive structure are located within the light-emitting region. The "first common signal line" and "second common signal line" mentioned here refer to signal lines shared by a portion of the light-emitting elements within the light-emitting area. For example, the "first common signal line" and "second common signal line" can be electrically connected to a row or column of light-emitting elements respectively to transmit signals to that row or column of light-emitting elements. Examples of the first common signal line and the second common signal line include, but are not limited to, the power line and the reference ground potential line mentioned above; that is, the first common signal line is one of the power line and the reference ground potential line, and the second common signal line is the other of the power line and the reference ground potential line. The first common signal line or the second common signal line can also be other signal lines on the light-emitting substrate, as long as at least a portion of the first common signal lines and at least a portion of the second common signal lines need to receive the same signal.

[0052] According to the light-emitting substrate provided in the embodiments of this application, a first conductive structure electrically connects at least a portion of the first common signal lines to each other, and a second conductive structure electrically connects at least a portion of the second common signal lines to each other. The first and second conductive structures extend along a second direction intersecting the first direction, and are located within the light-emitting area of ​​the light-emitting substrate. Therefore, the at least a portion of the first common signal lines electrically connected to each other via the first conductive structure and the at least a portion of the second common signal lines electrically connected to each other via the second conductive structure do not need to extend entirely to the bonding area of ​​the light-emitting substrate. Theoretically, only a single first common signal line and a single second common signal line need to extend to the bonding area. This allows signal lines for a larger number of light-emitting elements (e.g., signal lines for a larger number of columns of light-emitting units) to converge to a single bonding area, thereby reducing the number of bonding areas provided on the light-emitting substrate. It also avoids excessively large sizes for the light-emitting substrate and the bezel area of ​​the display device including the light-emitting substrate. In some embodiments, the first conductive structure electrically connects all the first common signal lines on the light-emitting substrate to each other, and the second conductive structure electrically connects all the second common signal lines on the light-emitting substrate to each other. In this case, the light-emitting substrate may only have one bonding area.

[0053] The following example illustrates a specific implementation of the light-emitting substrate, using the first common signal line and the second common signal line as examples of a power supply line and a reference ground potential line used to transmit power supply voltage to each light-emitting unit, respectively.

[0054] In some embodiments, the light-emitting area of ​​the light-emitting substrate includes an array of light-emitting units. Each light-emitting unit in the array includes K light-emitting elements from the plurality of light-emitting elements. The orthographic projections of the first conductive structure and the second conductive structure on the substrate do not overlap with the orthographic projections of the light-emitting elements in each light-emitting unit on the substrate, wherein K is greater than or equal to 2. The K light-emitting elements can be connected in series, and the interconnection of the positions of the K light-emitting elements can form patterns such as line segments and polygons.

[0055] Figure 3 illustrates an example of a partial plan view of a light-emitting substrate provided according to an embodiment of this application. As shown in Figure 3, the light-emitting area of ​​the light-emitting substrate includes multiple light-emitting units LU, each light-emitting unit including four light-emitting elements LED. These four light-emitting elements LED are connected in series to form a light-emitting unit LU, as shown by the dashed box in Figure 3. In this example, the positions of the four light-emitting elements LED form a rectangular pattern. It can be understood that each light-emitting element LED includes two electrodes. As shown in Figure 3, in the rectangular pattern formed by the four light-emitting elements LED connected in series, the first electrode of the light-emitting element LED at the lower left corner of the rectangle is connected to the power line VLED, the second electrode of the light-emitting element LED at the lower left corner of the rectangle is connected to the first electrode of the light-emitting element LED at the upper left corner of the rectangle, the second electrode of the light-emitting element LED at the lower right corner of the rectangle is electrically connected to the reference ground potential line GND via the driving circuit IC, and the first electrode of the light-emitting element LED at the lower right corner of the rectangle is electrically connected to the second electrode of the light-emitting element LED at the upper right corner of the rectangle. Thus, the four light-emitting elements LED in each light-emitting unit are connected in series between the power line VLED and the reference ground potential line GND, enabling each light-emitting element to emit light. Figure 3 also illustrates drive signal lines DL1, DL2, DL3, and DL4 electrically connected to the drive circuit IC. Examples of drive signal lines include, but are not limited to, drive circuit power lines, data lines, drive circuit input signal lines, and drive circuit output signal lines. This application does not impose any limitations on the model of the drive circuit IC or the drive signal lines, and the drive circuit and the corresponding drive signal lines are not the focus of this disclosure. In the example of Figure 3, the first body of multiple first common signal lines VLED and the second body of multiple second common signal lines GND extend in a first direction (e.g., vertical direction). The light-emitting substrate also includes a first conductive structure CD1 and a second conductive structure CD2 located on the substrate. The first conductive structure CD1 electrically connects the four first common signal lines VLED shown in Figure 3 to each other, and the second conductive structure CD2 electrically connects the four second common signal lines GND shown in Figure 3 to each other. The first conductive structure CD1 and the second conductive structure CD2 extend along a second direction (e.g., horizontal direction) intersecting the first direction, and the first conductive structure CD1 and the second conductive structure CD2 are located within the light-emitting area. In the embodiment of Figure 3, the first conductive structure CD1 and the second conductive structure CD2 may each include multiple jumpers, each jumper electrically connecting two adjacent first common signal lines VLED or two adjacent second common signal lines GND.

[0056] In some embodiments, at least one of the first conductive structure and the second conductive structure is located within the gap between light-emitting units in different rows of the light-emitting unit array. Alternatively, in another embodiment, at least one of the first conductive structure and the second conductive structure is located within the gap between different light-emitting elements of the same light-emitting unit in the light-emitting unit array. This reduces or avoids the impact of the first and second conductive structures on the normal operation or luminous performance of each light-emitting element. For example, as shown in FIG. 3, the first conductive structure CD1 is located within the gap between light-emitting units in different rows of the light-emitting unit array, while the second conductive structure CD2 is located within the gap between different light-emitting elements of the same light-emitting unit in the light-emitting unit array. Specifically, the first conductive structure CD1 is located within the gap between the two rows of light-emitting units closest to the bonding region B in the light-emitting unit array, and the second conductive structure CD2 is located within the gap between different light-emitting elements of the last row of light-emitting units closest to the bonding region in the light-emitting unit array.

[0057] Figure 4 illustrates an example of a partial plan view of a light-emitting substrate according to another embodiment of this application. As shown in Figure 4, the light-emitting substrate includes multiple first common signal lines CM1 and multiple second common signal lines CM2. The first body of the first common signal line CM1 and the first body of the second common signal line CM2 extend along a first direction D1. The first conductive structure CD1 and the second conductive structure CD2 extend along a second direction D2. The first direction D1 and the second direction D2 can be vertical and horizontal, respectively. Similar to the example shown in Figure 3, four light-emitting elements among the multiple light-emitting elements LEDs form a light-emitting unit, and each light-emitting unit LU has a rectangular pattern. In the embodiment of Figure 4, both the first conductive structure CD1 and the second conductive structure CD2 include continuous metal traces. The metal traces of the first conductive structure CD1 electrically connect the four first common signal lines CM1 in Figure 4 to each other, and the metal traces of the second conductive structure CD2 electrically connect the four second common signal lines CM2 in Figure 4 to each other. Similarly, specifically, the first conductive structure CD1 is located in the gap between the two rows of light-emitting units closest to the bonding region B in the light-emitting unit array, and the second conductive structure CD2 is located in the gap between different light-emitting elements of the last row of light-emitting units closest to the bonding region in the light-emitting unit array. Figure 5 illustrates an example of a partial plan view of a light-emitting substrate provided according to another embodiment of this application. The embodiment shown in Figure 5 is basically the same as the embodiment shown in Figure 3, except that the first conductive structure CD1 and the second conductive structure CD2, which include multiple jumpers, shown in Figure 3 are replaced with continuous metal traces in Figure 5.

[0058] As can be seen from Figures 3, 4, and 5, not all of the first and second common signal lines extend to the bonding area B of the electroluminescent substrate. Only one or a small portion of the first and second common signal lines extend to the bonding area B. In other words, most of the first and second common signal lines only extend within the light-emitting area, without needing to bend and change direction to reach the bonding area as in the example shown in Figure 1. This reduces the number of signal lines that need to be accommodated within the bezel area of ​​the light-emitting substrate, which is beneficial for reducing the area of ​​the bezel region. This is especially true when the first and second common signal lines are relatively wide power lines and reference ground potential lines, resulting in a more significant effect on achieving a narrow bezel. Furthermore, by utilizing the aforementioned first and second conductive structures, signal lines for more rows of light-emitting units can be converged to a single bonding area, thereby reducing the number of bonding areas on the light-emitting substrate and promoting cost reduction for both the light-emitting substrate and the display device.

[0059] Furthermore, compared to the embodiment shown in FIG. 3, the embodiments shown in FIG. 4 and FIG. 5 have additional technical advantages. In the embodiments of FIG. 4 and FIG. 5, the first conductive structure and the second conductive structure include continuous metal traces. The thickness of the metal traces can be made smaller than that of the jumper wires. For example, the thickness of the metal traces is between 5-50 μm, while the thickness of the jumper wires is typically 0.2-0.5 mm. Therefore, compared to the jumper-type first and second conductive structures shown in FIG. 3, the metal trace-type first and second conductive structures in the embodiments of FIG. 4 and FIG. 5 have less impact on the optical aspects of the light-emitting elements of the light-emitting substrate. Moreover, the metal trace-type first and second conductive structures can be made to any length, and are applicable even when the layout of the light-emitting elements in the light-emitting substrate is relatively dense (e.g., the pitch between the light-emitting elements is less than 5 mm). Therefore, the metal trace-type first and second conductive structures have a wider range of applications.

[0060] Figure 6 illustrates a partial plan view of a light-emitting substrate according to another embodiment of this application. As shown in Figure 6, multiple light-emitting elements in the light-emitting substrate form a light-emitting unit array, and each light-emitting unit LU (shown by the dashed box in Figure 6) includes six light-emitting elements. The light-emitting substrate also includes multiple first common signal lines CM1, multiple second common signal lines CM2, multiple driving circuit ICs (shown by the dashed ellipse in Figure 6), and a bonding area B. A first conductive structure CD1 electrically connects the multiple first common signal lines CM1 to each other, and a second conductive structure CD2 electrically connects the multiple second common signal lines CM2 to each other. Both the first conductive structure CD1 and the second conductive structure CD2 include metal traces. Figure 7 is a partial enlarged view of the light-emitting substrate shown in Figure 6.

[0061] In some embodiments, the light-emitting substrate further includes a protective layer located on the first common signal line and the second common signal line. The first conductive structure and the second conductive structure are located on the side of the protective layer facing away from the substrate. The protective layer includes a plurality of first conductive vias corresponding to at least a portion of the first common signal lines and a plurality of second conductive vias corresponding to at least a portion of the second common signal lines. The first conductive structure is electrically connected to the at least a portion of the first common signal lines via the plurality of first conductive vias, and the second conductive structure is electrically connected to the at least a portion of the second common signal lines via the plurality of second conductive vias. Figures 8 to 12 below illustrate partial cross-sectional schematic diagrams of light-emitting substrates provided according to different embodiments.

[0062] Figures 8 to 10 illustrate the situation before and after the second conductive structure is connected to the second conductive via, respectively. Figure 9 can be considered as an example of a partial cross-sectional view of the light-emitting substrate obtained along the dashed line A-A' in Figure 7. Referring to Figures 7 to 9, the light-emitting substrate includes a substrate SB, a first common signal line CM1, a second common signal line CM2 located on the substrate, and a protective layer PT located on the first common signal line CM1 and the second common signal line CM2. The first conductive structure CD1 and the second conductive structure CD2 are located on the side of the protective layer PT facing away from the substrate SB. The protective layer PT includes a plurality of first conductive vias VH2 corresponding to the first common signal line CM1 and a plurality of second conductive vias VH2 corresponding to the second common signal line CM2. The first conductive structure CD1 is electrically connected to at least a portion of the first common signal line CM1 through the plurality of first conductive vias VH1, and the second conductive structure CD2 is electrically connected to at least a portion of the second common signal line CM2 through the plurality of second conductive vias VH2. Although the partial cross-sectional views shown in Figures 8 and 9 do not show the first common signal line CM1, it can be understood that the first common signal line CM1 may be on the same layer as the second common signal line CM2. As shown in Figures 8 and 9, the protective layer may include a multilayer structure, each layer of which may be formed of an insulating material. The protective layer PT includes a first insulating layer PV1 (which may include thermoplastic polyvinyl chloride material PVX), a second insulating layer OC (which may include photoresist) located on the first insulating layer PV1, and a third insulating layer PV2 (which may include thermoplastic polyvinyl chloride material PVX) located on the second insulating layer OC. The light-emitting substrate may also include a buffer layer BF located between the substrate SB and the first insulating layer PV1. In some embodiments, a protective layer PT covering the first common signal line and the second common signal line may be formed on the substrate, and then a first conductive via and a second conductive via may be formed in the protective layer PT, as shown in Figure 8. Subsequently, a first conductive structure CD1 and a second conductive structure CD2 may be formed on the protective layer.

[0063] In some embodiments, each of the first conductive structure and the second conductive structure is formed of the same material as the first common signal line and the second common signal line. For example, in the embodiment of FIG. 9, both the first common signal line and the second common signal line may be formed of copper, and the first conductive structure CD1 and the second conductive structure CD2 may also be formed of copper. In some embodiments, the light-emitting substrate further includes light-emitting element interconnects (e.g., light-emitting element interconnects HL shown in FIG. 9) that connect the K light-emitting elements in the light-emitting unit in series. The light-emitting element interconnects HL are located on the side of the protective layer away from the substrate and are in the same layer as the first conductive structure and the second conductive structure. The first conductive structure and the second conductive structure can be fabricated in the same process as other conductor structures of the light-emitting substrate (e.g., light-emitting element interconnects HL connecting different light-emitting elements LEDs in series), thereby avoiding the complexity of the fabrication process of the light-emitting substrate. In this embodiment, the light-emitting substrate may also include an additional protective layer (e.g., a fourth insulating layer, not shown in FIG. 9) located on the first conductive structure CD1 and the second conductive structure CD2. The fourth insulating layer may cover the third insulating layer PV2 and the first conductive structure CD1 and the second conductive structure CD2.

[0064] Alternatively, in other embodiments, each of the first and second conductive structures includes a zero-ohm jumper. As shown in FIG10, the zero-ohm jumper CD2 electrically connects two second conductive vias VH2, thereby electrically connecting two second common signal lines CM2. In the embodiment of FIG10, a fourth insulating layer PV3 is formed on a third insulating layer PV2, constituting part of a protective layer PT, and the first and second conductive vias penetrate the fourth insulating layer PV3, the third insulating layer PV2, the second insulating layer OC, and the first insulating layer PV1 in the protective layer.

[0065] In some embodiments, each of the first conductive structure and the second conductive structure comprises a material different from the first common signal line and the second common signal line. For example, each of the first conductive structure and the second conductive structure comprises silver paste, and the first common signal line and the second common signal line comprise copper. FIG11 illustrates a partial cross-sectional view of a light-emitting substrate according to another embodiment of the present application. FIG11 is a partial cross-sectional view of the light-emitting substrate obtained along the dashed lines A1-A2 shown in FIG4. In this embodiment, all signal lines of the light-emitting substrate are in the same layer, the first common signal line CM1 and the second common signal line CM2 both comprise copper, for example, while each of the first conductive structure CD1 and the second conductive structure CD2 comprises silver paste. The first conductive structure and the second conductive structure can be fabricated using a screen-printed silver paste process. The minimum width of the metal traces formed by the screen-printed silver paste process can be approximately 50 μm, which can better meet the line spacing requirements of power lines and reference ground potential lines with larger line widths.

[0066] As shown in Figure 11, the light-emitting substrate includes a substrate SB, a first common signal line CM1, a second common signal line CM2, a protective layer PT, and a first conductive structure CD1. The light-emitting substrate also includes a light-reflecting layer RF located on the substrate, which covers the first conductive structure CD1 and the second conductive structure. The light-reflecting layer RF may include white oil, thereby enhancing the light reflection capability of the light-emitting substrate and improving its luminous effect as a backlight source. In the embodiment of Figure 1, the light-emitting substrate also includes a buffer layer BF located on the substrate, an insulating layer IN located between the first or second conductive structure and the protective layer PT, and a first and second conductive via in the protective layer PT passing through the insulating layer IN.

[0067] Figure 12 schematically illustrates a partial cross-sectional view of a light-emitting substrate according to another embodiment of this application. The embodiment shown in Figure 12 can be further described in conjunction with Figure 11; the cross-sectional view shown in Figure 12 can also be considered as a partial cross-sectional view of the light-emitting substrate obtained along the dashed lines A1-A2 shown in Figure 4. In this embodiment, the light-emitting substrate includes a light-reflecting layer RF, which covers a protective layer PT and is located between a first conductive structure or a second conductive structure and the protective layer PT. The light-reflecting layer RF includes a third conductive via VH3 communicating with the first or second conductive via. That is, the first or second conductive structure is located on the surface of the light-reflecting layer facing away from the substrate SB. The light-reflecting layer may include white oil, and the thickness of the light-reflecting layer can be made to be tens of micrometers, without the need to form an additional insulating layer IN on the protective layer PT as in Figure 11.

[0068] Figure 13 is a partial cross-sectional view of a light-emitting substrate according to an embodiment of this application, taken along the dashed lines B1-B2 shown in Figure 4, where the dashed lines B1-B2 are located at a light-emitting element (LED). As shown in Figure 13, the LED is electrically connected to a signal line CU on the substrate to receive a voltage signal that allows it to function properly. In this embodiment, the signal line CU and the aforementioned first and second common signal lines may be on the same layer (e.g., both on the surface of the buffer layer BF facing away from the substrate SB) and formed of the same material, such as copper. A protective layer PT may cover the signal line CU and the aforementioned first and second common signal lines. The protective layer PT has openings or vias at the locations corresponding to the signal line CU to allow the LED to be electrically connected to the signal line CU. In some embodiments, the light-emitting substrate further includes a conductive block PTA disposed in the vias of the protective layer. The conductive block PTA enhances the connection between the LED pins and the signal line CU and also protects the signal line CU. A light-reflecting layer RF, comprising white varnish, is disposed around the LED on the protective layer PT to reflect the light emitted by the LED. In addition, the light-emitting substrate also includes a protective adhesive layer PG disposed on the light-reflecting layer RF. The protective adhesive layer PG covers the light-emitting element LED and includes a transparent material so as not to affect the emission of light emitted from the LED.

[0069] In some embodiments, at least one of the first conductive structure and the second conductive structure includes a zero-ohm resistance jumper and a metal trace. The two ends of the zero-ohm resistance jumper and the two ends of the metal trace are respectively electrically connected to two first conductive holes or two second conductive vias among the plurality of first conductive holes, such that the zero-ohm resistance jumper and the metal trace are connected in parallel. This further reduces the overall resistance of the second conductive structure or the first conductive structure, and allows the current flowing through the first common signal line or the second common signal line to be carried by more current branches. Figure 14 illustrates a partial cross-sectional view of the light-emitting substrate provided according to this embodiment, which can be considered as being obtained along line AA' in Figure 7. As shown in Figure 14, the second conductive structure includes a zero-ohm resistance jumper CD21 and a metal trace CD22. The two ends of the zero-ohm resistance jumper CD21 and the two ends of the metal trace CD22 are respectively electrically connected to two second conductive vias VH2, such that the zero-ohm resistance jumper CD21 and the metal trace CD22 are connected in parallel. The metal trace CD22 can be similar to the second conductive structure CD2 shown in FIG9, and can be formed of metal materials such as copper. It can be fabricated in the same process as other conductive structures of the light-emitting substrate (e.g., wires that connect different light-emitting elements LEDs in series). As shown in FIG14, in addition to the protective layer PT and the second conductive via therein in the embodiment shown in FIG9, the light-emitting substrate also includes another protective layer PV3 located on the protective layer PT, and a fourth conductive via VH4 in the other protective layer PV3. The two ends of the zero-ohm jumper CD21 are electrically connected to the metal trace CD22 through the fourth conductive via VH4, so that the zero-ohm jumper CD21 and the metal trace CD22 are connected in parallel.

[0070] As previously mentioned, the substrate of the light-emitting substrate also includes a bonding region located outside the light-emitting area. In some embodiments, one of the first conductive structure and the second conductive structure is located within the gap between the two rows of light-emitting units closest to the bonding region in the light-emitting unit array. For example, Figures 3 to 6 all illustrate that the first conductive structure CD1 is located within the gap between the two rows of light-emitting units closest to the bonding region B in the light-emitting unit array. The other of the first and second conductive structures may be spaced one or two rows of light-emitting units apart from the first or second conductive structure located within the gap between the two rows of light-emitting units closest to the bonding region, or the other of the first and second conductive structures may be located within the gap between different light-emitting elements of the row of light-emitting units closest to the bonding region. That is, in this embodiment, the first and second conductive structures are disposed in the region of the light-emitting area close to the bonding region, rather than in other regions of the light-emitting area that are farther away from the bonding region. Since the current collected near the bonding area via the first common signal line and the second common signal line is relatively large, placing the first conductive structure and the second conductive structure in the region near the bonding area of ​​the light-emitting area allows the first conductive structure and the second conductive structure to share the large current near the bonding area on the first common signal line and the second common signal line, preventing the first common signal line and the second common signal line from being damaged by excessive current.

[0071] As shown in Figures 3 to 6, in some embodiments, the light-emitting substrate further includes a driving circuit array located on the substrate. Each driving circuit IC in the driving circuit array is electrically connected to at least one light-emitting unit LU in the light-emitting unit array. Each row of driving circuit ICs in the driving circuit array is located within the gaps between light-emitting units LU in different rows of the light-emitting unit array, and each row of driving circuits is spaced at least one row of light-emitting units apart from the first conductive structure CD1 or the second conductive structure CD2 in the first direction. This reduces the mutual influence between the first conductive structure or the second conductive structure and the driving circuit. In the embodiment of Figure 6, the first conductive structure CD1 and the second conductive structure CD2 are alternately distributed with a portion of the driving circuit rows in the driving circuit array within the gaps between light-emitting units LU in different rows.

[0072] In some embodiments, the light-emitting substrate further includes drive circuit signal lines connected to the drive circuit, and the substrate further includes a fan-out region located between the light-emitting region and the bonding region, wherein the drive circuit signal lines extend from the light-emitting region, through the fan-out region, and reach the bonding region. In Figures 4, 5, and 6, the fan-out region FT is identified by a long dashed rectangle. The fan-out region FT can be considered as a transition region before the various signal lines on the light-emitting substrate converge to reach the bonding region. The at least portion of the first common signal lines electrically connected to each other via the first conductive structure include multiple first-length power lines and at least one second-length power line. The second-length power line extends from the light-emitting region through the fan-out region to the bonding region. The first-length power lines extend within the light-emitting region, and their orthogonal projections on the substrate do not overlap with the fan-out region and the bonding region. The at least portion of the second common signal lines electrically connected to each other via the second conductive structure include multiple first-length reference ground potential lines and at least one second-length reference ground potential line. The second-length reference ground potential line extends from the light-emitting region through the fan-out region to the bonding region. The first-length reference ground potential line extends within the light-emitting region, and its orthogonal projection on the substrate does not overlap with the fan-out region and the bonding region. For example, for the four power lines CM1 and four reference ground potential lines CM2 shown in Figure 4, the first common signal line marked with VLED in the middle position is the second length power line. The second length power line extends from the light-emitting area through the fan-out area FT to the bonding area B. The other three first common signal lines are the first length power lines. The first length power lines extend in the light-emitting area without passing through the fan-out area FT and the bonding area B (that is, the orthographic projection of the first length power line on the substrate does not overlap with the fan-out area and the bonding area). The length of the first length power line is less than the length of the second length power line. Similarly, the second common signal line marked GND in the middle is a second-length reference ground potential line, which extends from the light-emitting region through the fan-out region FT to the bonding region B. The other three second common signal lines are first-length reference ground potential lines, which extend within the light-emitting region without passing through the fan-out region FT and the bonding region B (i.e., the orthographic projection of the first-length reference ground potential line onto the substrate does not overlap with the fan-out region and the bonding region). The length of the first-length reference ground potential line is less than the length of the second-length reference ground potential line. Figures 5 and 6 also illustrate first common signal lines and second common signal lines of different lengths. As shown in Figures 5 and 6, only the first and second common signal lines located directly above the bonding region extend through the fan-out region FT to the bonding region B; the other first and second common signal lines do not extend from the light-emitting region to the fan-out region FT.Therefore, it can be further understood that the number of first and second common signal lines extending within the fan-out area is significantly reduced, thereby helping to reduce the area of ​​the fan-out area and facilitating the realization of narrow bezels in the light-emitting substrate and display device. Of course, where fan-out area wiring allows, additional conductive structures can be provided in the fan-out area, connected to the first or second conductive structure and extending to the bonding area, further helping to disperse the current flowing through the first and second common signal lines near the bonding area. For example, in the example of Figure 4, the first conductive structure CD1 also includes an "L"-shaped branch conductive structure, and the second conductive structure CD2 also includes another segment-type branch conductive structure extending in the first direction. The "L"-shaped branch conductive structure and the segment-type branch conductive structure extend to the fan-out area FT and are connected to the bonding area via metal traces within the fan-out area.

[0073] In the embodiments of Figures 4 and 5, the plurality of first-length power lines are distributed along the second direction D2 on both sides of the at least one second-length power line, and the plurality of first-length reference ground potential lines are distributed along the second direction D2 on both sides of the at least one second-length reference ground potential line.

[0074] In some embodiments, the width of the first end of the at least one second-length power line near the bonding region is greater than the width of the first body of the second-length power line, and the width of the first end of the at least one second-length reference ground potential line near the bonding region is greater than the width of the second body of the second-length reference ground potential line. As shown in FIG5, the width of the first end of the second-length power line VLED near the bonding region B is significantly greater than the width of its first body, and the width of the first end of the second-length reference ground potential line GND near the bonding region B is greater than the width of its second body. This improves the current carrying capacity of the second-length power line and the second-length reference ground potential line.

[0075] According to some embodiments of this application, the K light-emitting elements in the light-emitting unit of the light-emitting substrate are connected in series to form a first light-emitting unit pattern. The light-emitting substrate also includes an additional light-emitting unit row located in the fan-out region. Each additional light-emitting unit in the additional light-emitting unit row includes multiple additional light-emitting elements, and the multiple additional light-emitting elements are connected in series to form a second light-emitting unit pattern. For example, the light-emitting substrate shown in FIG6 has an additional light-emitting unit row in the fan-out region FT, and the second light-emitting unit pattern is substantially consistent with the first light-emitting unit pattern in the light-emitting region. By setting an additional light-emitting unit row in the fan-out region, the actual light-emitting surface area of ​​the light-emitting substrate can be increased, and the brightness of the border area can be improved.

[0076] In another embodiment, as shown in FIG15, a partially enlarged schematic diagram of the boundary between the fan-out region and the light-emitting region of the light-emitting substrate is illustrated. Each light-emitting unit includes six light-emitting elements connected in series. The six light-emitting elements LED1, LED2, LED3, LED4, LED5, and LED6 in the bottom light-emitting unit row BL closest to the bonding region in the light-emitting unit array are connected in series to form a first light-emitting unit pattern. The light-emitting units in the additional light-emitting unit row AL in the fan-out region include six light-emitting elements LEDa, LEDb, LEDc, LEDd, LEDe, and LEDf connected in series, forming a second light-emitting unit pattern. A portion of the first light-emitting unit pattern of the light-emitting unit in the bottom light-emitting unit row BL closest to the bonding region in the light-emitting unit array and a portion of the second light-emitting unit pattern of the additional light-emitting unit in the additional light-emitting unit row AL are symmetrical about the gap extending along the second direction between the bottom light-emitting unit row BL and the additional light-emitting unit row AL. For example, the pattern formed by light-emitting elements LED1, LED2, LED3, and LED4 in the first light-emitting unit pattern is symmetrical to the pattern formed by light-emitting elements LEDa, LEDb, LEDc, and LEDd in the second light-emitting pattern about the gap extending along the second direction between the bottom light-emitting unit row BL and the additional light-emitting unit row AL. The axis of symmetry can be simplified as the double-arrow line CC' in Figure 15. This optimizes the layout of the drive signal lines within the fan-out area, preventing the distance between the drive signal lines and the light-emitting elements in the additional light-emitting unit row from being too small or even overlapping with the light-emitting elements. This helps the light-emitting elements in the additional light-emitting unit row avoid the drive signal lines. For example, in the embodiment of Figure 15, the drive signal lines can be placed within the gap between two different rows of light-emitting elements in the additional light-emitting unit.

[0077] According to some embodiments of this application, at least one of the first conductive structure and the second conductive structure includes a plurality of sub-conductive structures. Each of the plurality of sub-conductive structures is located in the gap between light-emitting units in different rows of the light-emitting unit array. The plurality of sub-conductive structures are electrically connected to each other via the at least a portion of the first common signal line or the at least a portion of the second common signal line. The bottom sub-conductive structure closest to the bonding region among the plurality of sub-conductive structures includes a zero-ohm resistance jumper. The other sub-conductive structures among the plurality of sub-conductive structures, except for the bottom sub-conductive structure, are formed of the same material as the first common signal line and the second common signal line. Figure 16 illustrates the electrical connection between the plurality of first common signal lines and the first conductive structure, and the electrical connection between the plurality of second common signal lines and the second conductive structure of the light-emitting substrate provided according to an embodiment of this application, and schematically illustrates the fan-out region FT and the bonding region B. For simplicity, Figure 16 omits other components such as light-emitting units, driving circuits, and driving signal lines. In the embodiment shown in Figure 16, the first conductive structure includes two sub-conductive structures CD1a and CD1b, and the second conductive structure includes two sub-conductive structures CD2a and CD2b. Each sub-conductive structure CD1a, CD1b, CD2a, and CD2b is located within the gaps between light-emitting units in different rows of the light-emitting unit array. Sub-conductive structures CD1a and CD1b are electrically connected to each other via four first common signal lines CM1, and sub-conductive structures CD2a and CD2b are electrically connected to each other via four second common signal lines CM2. The bottom sub-conductive structure CD1b, closest to the bonding region B among sub-conductive structures CD1a and CD1b, includes a zero-ohm resistance jumper. The bottom sub-conductive structure CD2b, closest to the bonding region B among sub-conductive structures CD2a and CD2b, is formed of the same material as the first common signal lines CM1 and the second common signal lines CM2. Zero-ohm jumpers have a greater current carrying capacity. The closer to the bonding area B, the greater the current convergence of the common signal lines through the first or second conductive structure. Therefore, the bottom sub-conductive structures CD1b and CD2b, which are closest to the bonding area B, include zero-ohm jumpers, which helps to improve the overall current carrying capacity of the circuit and prevent damage to the common signal lines and the first or second conductive structure due to excessive current. The other sub-conductive structures CD1a, CD1b, CD2a, and CD2b, except for the bottom sub-conductive structures CD1b and CD2b, can be, for example, formed of copper.

[0078] In some embodiments, the bottom sub-conductive structure described above further includes an additional conductive structure connected in parallel with the zero-ohm resistance jumper. This additional conductive structure is formed of the same material as the first common signal line and the second common signal line. For example, this additional conductive structure can be a copper metal trace. Thus, the zero-ohm resistance jumper and the copper metal trace are connected in parallel to form the bottom sub-conductive structure, thereby not only improving the overall current carrying capacity of the circuit but also reducing the power loss of the first or second conductive structure itself. The bottom sub-conductive structure can be illustrated with reference to FIG14. The bottom sub-conductive structure may include a zero-ohm resistance jumper CD21 and a metal trace CD22. The metal trace CD22 is the additional conductive structure described above. The two ends of the zero-ohm resistance jumper CD21 are electrically connected to the two ends of the metal trace CD22 via a fourth conductive via VH4, so that the zero-ohm resistance jumper CD21 and the metal trace CD22 are connected in parallel.

[0079] According to some embodiments of this application, multiple first common signal lines and multiple second common signal lines of the light-emitting substrate are alternately arranged in the second direction, for example, as shown in the embodiments illustrated in Figures 4, 5, 15, and 16. The first common signal line further includes a first protrusion extending from the first body toward an adjacent second common signal line along the second direction. The adjacent second common signal line further includes a second protrusion extending from the second body toward the first common signal line along a third direction, opposite to the second direction. Figure 5 illustrates the first protrusion P1 and the second protrusion P2. Figure 17 illustrates a partially enlarged schematic diagram of some first common signal lines and second common signal lines on a light-emitting substrate provided according to some embodiments of this application. As shown in Figure 17, the first common signal line CM1 includes a first protrusion P1 extending from the first body toward an adjacent second common signal line CM2 along the second direction D2. The adjacent second common signal line CM2 further includes a second protrusion P2 extending from the second body toward the first common signal line CM1 along a third direction D3, opposite to the second direction D2.

[0080] Referring again to Figure 17, according to some embodiments of this application, the first common signal line CM1 and the adjacent second common signal line CM2 are located between two adjacent columns of light-emitting units in the light-emitting unit array. Figure 17 illustrates two adjacent light-emitting units LU with dashed boxes, and these two light-emitting units LU belong to two adjacent columns of light-emitting units respectively. The second protrusion P2 is located within the area of ​​a single light-emitting unit LU in the light-emitting unit array, and the first protrusion P2 is located between two adjacent rows of light-emitting units in the light-emitting unit array.

[0081] According to some embodiments of this application, the first common signal line further includes a third protrusion extending from the first body toward an adjacent second common signal line along the third direction D3. The first protrusion of the first common signal line in at least a portion of the first common signal lines is electrically connected to the third protrusion of the adjacent first common signal line via the first conductive structure. The provision of the third protrusion can reduce the length requirements of the first or second conductive structure, facilitating electrical connections between the various first or second common signal lines. As shown in FIG17, the first common signal line CM1 includes a third protrusion P3 extending from the first body toward an adjacent second common signal line CM2 along the third direction D3. The first protrusion P1 of the first common signal line CM1 is electrically connected to the third protrusion P3 of the adjacent first common signal line via the first conductive structure CD1.

[0082] Figure 18 illustrates a partially enlarged schematic diagram of some first common signal lines and second common signal lines on a light-emitting substrate according to another embodiment of this application. Multiple first common signal lines CM1 and multiple second common signal lines CM2 are arranged alternately in a second direction D2. Each first common signal line CM1 further includes a first protrusion P1 extending from the first body toward an adjacent second common signal line CM2 along the second direction D2. Each adjacent second common signal line also includes a second protrusion P2 extending from the second body toward the first common signal line CM1 along a third direction D3, opposite to the second direction D2. Each of the first protrusions P1 and P2 is located within the gap between light-emitting units in adjacent rows of the light-emitting unit array. The first protrusion P1 of at least a portion of the first common signal lines is electrically connected to the first body of the adjacent first common signal line CM1 via a first conductive structure CD1. The second protrusion P2 of at least a portion of the second common signal lines is electrically connected to the second body of the adjacent second common signal line CM2 via the second conductive structure CD2.

[0083] Figure 19 illustrates a partially enlarged schematic diagram of some first common signal lines and second common signal lines on a light-emitting substrate according to another embodiment of this application. In this embodiment, multiple first common signal lines CM1 and multiple second common signal lines CM2 are arranged alternately in a second direction D2. The first common signal line CM1 further includes a first protrusion P1 extending from the first body toward the adjacent second common signal line along the second direction D2. The first protrusion P1 includes a hollow portion. The light-emitting substrate further includes a conductive block D located in the hollow portion and isolated from the first protrusion P1. The conductive block D is electrically connected to two adjacent second common signal lines CM2 in the at least a portion of the second common signal lines via a second conductive structure CD2. The first protrusion P1 of the first common signal line in the at least a portion of the first common signal lines is electrically connected to the first body of the adjacent first common signal line CM1 via the first conductive structure CD1. In this embodiment, by using the aforementioned conductive block, the first conductive structure and the second conductive structure can be disposed in the same gap between two adjacent rows of light-emitting units in the light-emitting unit array. Moreover, compared to other embodiments, there is no dedicated second protrusion for the second common signal line, thereby reducing the influence of the first conductive structure and the second conductive structure on the light-emitting element in the light-emitting unit.

[0084] In summary, according to the light-emitting substrates provided in the above embodiments of this application, the first conductive structure electrically connects at least a portion of the first common signal lines to each other, and the second conductive structure electrically connects at least a portion of the second common signal lines to each other. The first and second conductive structures are located within the light-emitting area of ​​the light-emitting substrate. Thus, the at least a portion of the first common signal lines electrically connected to each other via the first conductive structure and the at least a portion of the second common signal lines electrically connected to each other via the second conductive structure do not need to extend entirely to the bonding area of ​​the light-emitting substrate. This allows signal lines for a larger number of light-emitting elements (e.g., signal lines for more columns of light-emitting units) to converge to a single bonding area, reducing the number of bonding areas on the light-emitting substrate and avoiding excessively large sizes for the light-emitting substrate and the bezel area of ​​the display device including the light-emitting substrate. In some embodiments, the first conductive structure electrically connects all the first common signal lines on the light-emitting substrate to each other, and the second conductive structure electrically connects all the second common signal lines on the light-emitting substrate to each other. In this case, only a single first common signal line and a single second common signal line can extend to the bonding area, and the light-emitting substrate can have only one bonding area. Correspondingly, the number of flip-chip films or flexible printed circuit boards required is greatly reduced, lowering the cost of light-emitting substrates and display devices. At the same time, it can also promote the improvement of the yield of light-emitting substrates and display devices, especially in cases where it is necessary to bend the flip-chip film or flexible printed circuit board to the back of the light-emitting substrate.

[0085] In the case of the first common signal line, the second common signal line, the power line, and the reference ground potential line, the above embodiments are more effective in achieving a narrow bezel. The power line and reference ground potential line, which provide operating voltage to the light-emitting element and form a current loop, need to carry a large current to ensure normal operation of the light-emitting element. Simultaneously, they are required to have minimal resistance to reduce losses. Therefore, the linewidth of the power line and reference ground potential line is much larger than that of other signal lines, and correspondingly, the line spacing between different power lines or reference ground potential lines is also required to be larger. For example, in the example described previously with reference to Figures 1 and 2, the linewidth of the power line VLED and the reference ground potential line GND is approximately 850 μm, and the line spacing between different power lines or reference ground potential lines is approximately 200 μm. The numerous power lines and reference ground potential lines reach the bonding area through the fan-out area, inevitably resulting in a large bezel size. For example, the width of the bottom bezel (the distance from the center of the light-emitting element closest to the bonding area in the first direction to the outer edge of the display substrate) may reach 5 to 10 millimeters. However, based on the embodiments described in Figures 4 or 5, the width of the bottom bezel can be reduced to 2 to 5 millimeters.

[0086] Another embodiment of this application provides a display device, which includes a light-emitting substrate as described in any of the foregoing embodiments. This light-emitting substrate can serve as a backlight substrate for the display device. Therefore, the display device can be a liquid crystal display or a liquid crystal display panel that includes liquid crystals. The display device may also include an array substrate, a color filter substrate, and a liquid crystal layer located between the array substrate and the color filter substrate. Examples of display devices include, but are not limited to, any electronic device with display functionality, such as a mobile phone, computer, or PDA.

[0087] Another embodiment of this application provides a method for fabricating a light-emitting substrate, which may include the following steps: S1, fabricating a first conductive layer on a substrate, the first conductive layer including the aforementioned plurality of first common signal lines and plurality of second common signal lines (e.g., power lines and reference ground potential lines). In some embodiments, the first conductive layer may further include, for example, the aforementioned driving signal lines. S2, fabricating a protective layer on the substrate covering the first conductive layer, the protective layer may include some openings exposing the aforementioned first common signal lines and second common signal lines. S3, fabricating a first conductive structure and a second conductive structure on the protective layer, the first conductive structure electrically connecting at least a portion of the plurality of first common signal lines to each other, and the second conductive structure electrically connecting at least a portion of the plurality of second common signal lines to each other. In some embodiments, the first conductive structure and the second conductive structure may each include silver paste material, and the first conductive structure and the second conductive structure may be formed by screen printing silver paste. In some embodiments, to enhance the overall light-emitting effect of the light-emitting substrate, the above method may further include: S4, forming a light-reflecting layer on the first conductive structure and the second conductive structure, the light-reflecting layer surrounding each light-emitting element. The light-reflecting layer includes a white oil layer. The white oil layer can promote the emission of light emitted by the light-emitting element in the direction away from the light-emitting surface of the light-emitting substrate, thereby enhancing the brightness of the light-emitting substrate. Alternatively, step S4 can be performed before step S3, that is, a light-reflecting layer covering the protective layer is first formed on the protective layer, and then the first conductive structure and the second conductive structure are formed on the light-reflecting layer.

[0088] It will be understood that although the terms first, second, third, etc., may be used herein to describe various devices, elements, components, or parts, these devices, elements, components, or parts should not be limited by these terms, but only indicate a distinction in name. Furthermore, the term "electrical connection" as used herein includes both "direct connection" and "indirect connection." Although the technical solutions of this application have been described in conjunction with some embodiments, the scope of protection of this application is not limited to the specific forms set forth herein, and the scope of this application is defined by the appended claims.

Claims

1. A light-emitting substrate, comprising: A substrate, the substrate including a light-emitting region; A plurality of light-emitting elements are located on the substrate, and the plurality of light-emitting elements are located within the light-emitting area; as well as The substrate has multiple first common signal lines and multiple second common signal lines located on it and electrically connected to the plurality of light-emitting elements. Each of the multiple first common signal lines includes a first body extending along a first direction, and each of the multiple second common signal lines includes a second body extending along the first direction. The first direction extends from a first edge of the substrate to a second edge directly opposite the first edge. The light-emitting substrate further includes a first conductive structure and a second conductive structure located on the substrate. The first conductive structure electrically connects at least a portion of the plurality of first common signal lines to each other, and the second conductive structure electrically connects at least a portion of the plurality of second common signal lines to each other. The first conductive structure and the second conductive structure extend along a second direction intersecting the first direction, and the first conductive structure and the second conductive structure are located within the light-emitting area.

2. The light-emitting substrate according to claim 1, wherein the light-emitting region includes an array of light-emitting units, each light-emitting unit in the array of light-emitting units includes K light-emitting elements among the plurality of light-emitting elements, wherein the orthographic projections of the first conductive structure and the second conductive structure on the substrate do not overlap with the orthographic projections of the light-emitting elements in each light-emitting unit on the substrate, wherein K is greater than or equal to 2.

3. The light-emitting substrate according to claim 2, wherein at least one of the first conductive structure and the second conductive structure is located in the gap between light-emitting units in different rows of the light-emitting unit array.

4. The light-emitting substrate according to claim 2, wherein at least one of the first conductive structure and the second conductive structure is located within the gap between different light-emitting elements of the same light-emitting unit in the light-emitting unit array.

5. The light-emitting substrate according to claim 1, wherein the first common signal line includes a power line for transmitting power supply voltage to each light-emitting unit in the light-emitting unit array, and the second common signal line includes a reference ground potential line.

6. The light-emitting substrate according to claim 2, wherein the light-emitting substrate further comprises a protective layer located on the first common signal line and the second common signal line, the first conductive structure and the second conductive structure being located on the side of the protective layer facing away from the substrate, the protective layer comprising a plurality of first conductive vias corresponding to at least a portion of the first common signal lines, and a plurality of second conductive vias corresponding to at least a portion of the second common signal lines. The first conductive structure is electrically connected to at least a portion of the first common signal lines via the plurality of first conductive vias, and the second conductive structure is electrically connected to at least a portion of the second common signal lines via the plurality of second conductive vias.

7. The light-emitting substrate according to claim 6, wherein each of the first conductive structure and the second conductive structure comprises a material different from the first common signal line and the second common signal line.

8. The light-emitting substrate according to claim 7, wherein each of the first conductive structure and the second conductive structure comprises silver paste, and the first common signal line and the second common signal line comprise copper.

9. The light-emitting substrate according to claim 8, wherein the light-emitting substrate further comprises a light-reflecting layer located on the substrate, the light-reflecting layer covering the first conductive structure and the second conductive structure.

10. The light-emitting substrate according to claim 8, wherein the light-emitting substrate further comprises a light-reflecting layer, the light-reflecting layer covering the protective layer and located between the first conductive structure or the second conductive structure and the protective layer, the light-reflecting layer comprising a third conductive via communicating with the first conductive via or the second conductive via.

11. The light-emitting substrate according to claim 6, wherein the light-emitting substrate further includes light-emitting element interconnecting lines that connect the K light-emitting elements in the light-emitting unit in series, the light-emitting element interconnecting lines being located on the side of the protective layer away from the substrate and being in the same layer as the first conductive structure and the second conductive structure.

12. The light-emitting substrate of claim 6, wherein each of the first conductive structure and the second conductive structure includes a zero-ohm resistance jumper.

13. The light-emitting substrate according to claim 2, wherein the substrate further comprises a bonding region located outside the light-emitting region, and one of the first conductive structure and the second conductive structure is located in the gap between the two rows of light-emitting units closest to the bonding region in the light-emitting unit array.

14. The light-emitting substrate according to claim 13, wherein the first conductive structure and the other of the second conductive structure are located in the gap between different light-emitting elements in the row of light-emitting units closest to the bonding region in the light-emitting unit array.

15. The light-emitting substrate according to claim 2, wherein the light-emitting substrate further comprises a driving circuit array located on the substrate, each driving circuit in the driving circuit array being electrically connected to at least one light-emitting unit in the light-emitting unit array, wherein each row of driving circuits in the driving circuit array is located in the gap between light-emitting units in different rows of the light-emitting unit array, and each row of driving circuits is spaced apart from the first conductive structure or the second conductive structure by at least one row of light-emitting units in the first direction.

16. The light-emitting substrate according to claim 15, wherein the light-emitting substrate further includes a driving circuit signal line connected to the driving circuit, the substrate further includes a fan-out region located between the light-emitting region and the bonding region, and the driving circuit signal line extends from the light-emitting region, through the fan-out region, to the bonding region. The at least portion of the first common signal line includes multiple first-length power lines and at least one second-length power line. The second-length power line extends from the light-emitting region through the fan-out region to the bonding region. The first-length power line extends within the light-emitting region, and its orthographic projection on the substrate does not overlap with the fan-out region and the bonding region. The at least a portion of the second common signal lines include multiple first-length reference ground potential lines and at least one second-length reference ground potential line. The second-length reference ground potential line extends from the light-emitting region through the fan-out region to the bonding region. The first-length reference ground potential line extends within the light-emitting region, and the orthographic projection of the first-length reference ground potential line on the substrate does not overlap with the fan-out region and the bonding region.

17. The light-emitting substrate according to claim 15, wherein the plurality of first-length power lines are distributed along the second direction on both sides of the at least one second-length power line, and the plurality of first-length reference ground potential lines are distributed along the second direction on both sides of the at least one second-length reference ground potential line.

18. The light-emitting substrate according to claim 17, wherein the width of the first end of the at least one second-length power line near the bonding region is greater than the width of the first body of the second-length power line, and the width of the first end of the at least one second-length reference ground potential line near the bonding region is greater than the width of the second body of the second-length reference ground potential line.

19. The light-emitting substrate according to claim 16, wherein the K light-emitting elements in the light-emitting unit are connected in series to form a first light-emitting unit pattern, wherein the light-emitting substrate further includes an additional light-emitting unit row located in the fan-out region, each additional light-emitting unit in the additional light-emitting unit row including a plurality of additional light-emitting elements, the plurality of additional light-emitting elements being connected in series to form a second light-emitting unit pattern. A portion of the first light-emitting unit pattern of the light-emitting unit in the bottom light-emitting unit row closest to the binding area in the light-emitting unit array is symmetrical with respect to a portion of the second light-emitting unit pattern of the additional light-emitting unit in the additional light-emitting unit row about the gap extending along the second direction between the bottom light-emitting unit row and the additional light-emitting unit row.

20. The light-emitting substrate according to claim 2, wherein at least one of the first conductive structure and the second conductive structure comprises a plurality of sub-conductive structures, each of the plurality of sub-conductive structures being located within the gaps between light-emitting units in different rows of the light-emitting unit array, and the plurality of sub-conductive structures being electrically connected to each other via the at least a portion of the first common signal line or the at least a portion of the second common signal line. The bottom sub-conductive structure closest to the bonding region among the plurality of sub-conductive structures includes a zero-ohm resistance jumper, and the other sub-conductive structures among the plurality of sub-conductive structures, excluding the bottom sub-conductive structure, are formed of the same material as the first common signal line and the second common signal line.

21. The light-emitting substrate of claim 20, wherein the bottom sub-conductive structure further comprises an additional conductive structure connected in parallel with the zero-ohm resistance jumper, the additional conductive structure being formed of the same material as the first common signal line and the second common signal line.

22. The light-emitting substrate according to claim 2, wherein the plurality of first common signal lines and the plurality of second common signal lines are alternately arranged in the second direction, the first common signal line further includes a first protrusion extending from the first body toward an adjacent second common signal line along the second direction, and the adjacent second common signal line further includes a second protrusion extending from the second body toward the first common signal line along a third direction, the third direction being opposite to the second direction.

23. The light-emitting substrate according to claim 22, wherein the first common signal line and the adjacent second common signal line are located between two adjacent columns of light-emitting units in the light-emitting unit array, wherein one of the first protrusion and the second protrusion is located within the region of a single light-emitting unit in the light-emitting unit array, and the other of the first protrusion and the second protrusion is located between two adjacent rows of light-emitting units in the light-emitting unit array.

24. The light-emitting substrate of claim 22, wherein the first common signal line further includes a third protrusion extending from the first body toward an adjacent second common signal line along the third direction, wherein the first protrusion of the first common signal line in at least a portion of the first common signal lines is electrically connected to the third protrusion of the adjacent first common signal line via the first conductive structure.

25. The light-emitting substrate of claim 22, wherein each of the first protrusion and the second protrusion is located within the gap between light-emitting units in adjacent rows of the light-emitting unit array, wherein the first protrusion of the first common signal line in at least a portion of the first common signal lines is electrically connected to the first body of the adjacent first common signal line via the first conductive structure, and the second protrusion of the second common signal line in at least a portion of the second common signal lines is electrically connected to the second body of the adjacent second common signal line via the second conductive structure.

26. The light-emitting substrate according to claim 2, wherein the plurality of first common signal lines and the plurality of second common signal lines are alternately arranged in the second direction, the first common signal lines further include a first protrusion extending from the first body toward an adjacent second common signal line along the second direction, the first protrusion including a hollow portion, the light-emitting substrate further including a conductive block located in the hollow portion and isolated from the first protrusion, wherein the conductive block is electrically connected to two adjacent second common signal lines among the at least a portion of the second common signal lines via the second conductive structure, and the first protrusion of the first common signal line among the at least a portion of the first common signal lines is electrically connected to the first body of the adjacent first common signal line via the first conductive structure.

27. A display device comprising a light-emitting substrate according to any one of claims 1-26.

Images