Display panel and display device

Abstract

The present invention provides a display panel and a display device, wherein the display panel comprises: a base substrate, a cathode layer located in a display area and a non-display area of ​​the base substrate, and an auxiliary cathode structure located in the non-display area; wherein the auxiliary cathode structure comprises at least two conductive rings surrounding the display area in a direction from the display area to the non-display area; an inner conductive ring of the at least two conductive rings, located closer to the display area, is coupled to the cathode layer, and the inner conductive rings are arranged around the display area; an outer conductive ring of the at least two conductive rings, located away from the display area, is coupled to a corresponding binding electrode located in a binding area of ​​the base substrate via two oppositely arranged terminals, and receives a driving signal from a driving chip in the binding area via the two terminals; and adjacent two conductive rings of the at least two conductive rings are coupled via an overlapping portion, wherein the resistance of the overlapping portion is greater than that of the inner conductive ring. This is used to improve in-plane brightness uniformity.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a display panel and a display device. Background Art

[0002] The increasing demand for larger-sized microdisplays in the industry has led to a surge in demand. Compared to existing product architectures, the thin cathode leads to a larger current and resistance drop (IR drop), resulting in poor brightness uniformity. For example, for microdisplays larger than 1.5 inches, the current in-plane brightness uniformity is only 30%, failing to meet product specifications. Summary of the Invention

[0003] The present invention provides a display panel and a display device for improving the uniformity of brightness within a surface.

[0004] In a first aspect, an embodiment of the present invention provides a display panel, including:

[0005] A base substrate, a cathode layer located in a display area and a non-display area of ​​the base substrate, and an auxiliary cathode structure located in the non-display area;

[0006] Among them, along the direction from the display area to the non-display area, the auxiliary cathode structure includes at least two conductive rings surrounding the display area; the inner conductive ring close to the display area of ​​the at least two conductive rings is coupled to the cathode layer, and the inner conductive ring is arranged around the display area; the outer conductive ring away from the display area of ​​the at least two conductive rings is coupled to the corresponding binding electrode located in the binding area of ​​the substrate through two oppositely arranged terminals, and receives the driving signal from the driving chip in the binding area through the two terminals; two adjacent conductive rings of the at least two conductive rings are coupled through a overlapping portion, and the resistance value of the overlapping portion is greater than the resistance value of the inner conductive ring.

[0007] In a possible implementation, each overlapping portion includes a plurality of sub-joint units extending in a direction from the display area to the non-display area.

[0008] In a possible implementation, the at least two conductive rings include two conductive rings including the inner conductive ring and the outer conductive ring, and the inner conductive ring and the outer conductive ring include the plurality of sub-bonding units arranged in sequence.

[0009] In a possible implementation, the resistance value of each sub-bonding unit is negatively correlated with the distance between the corresponding sub-bonding unit and the binding area.

[0010] In a possible implementation, the width of each sub-joint unit in a direction intersecting the extending direction is positively correlated with the distance from the corresponding sub-joint unit to the binding area.

[0011] In a possible implementation, the orthographic projection of each sub-joint unit on the base substrate is arranged in a non-linear shape.

[0012] In a possible implementation, the length of each sub-joint unit in the extension direction is negatively correlated with the distance from the corresponding sub-joint unit to the binding area.

[0013] In a possible implementation, each overlapping portion is made of the same material as the cathode layer, and a thickness of each overlapping portion is less than a thickness of the cathode layer.

[0014] In a possible implementation, the distribution density of some sub-overlapping units near the corner areas of the display area is smaller than the distribution density of some sub-overlapping units near the non-corner areas of the display area except the corner areas.

[0015] In a possible implementation, a ratio of a resistance value of the overlapping portion to a resistance value of the inner conductive ring is greater than 1000:1.

[0016] In a possible implementation, it further includes a plurality of light-emitting devices arranged in the display area, and an auxiliary conductive structure is provided on the side of the cathode layer facing away from the base substrate, and the auxiliary conductive structure has a first opening at each light-emitting device.

[0017] In one possible implementation, it further includes a pixel definition layer located on the side of the cathode layer close to the base substrate and having a second opening at each light-emitting device; the orthographic projection of the second opening on the base substrate completely falls within the area of ​​the orthographic projection of the first opening on the base substrate.

[0018] In a possible implementation, the thickness of the cathode layer ranges from 2000 angstroms to 6000 angstroms.

[0019] In a possible implementation, the auxiliary conductive structure is composed of TiN / Al / TiN.

[0020] In a possible implementation, an etch stop layer surrounding the auxiliary conductive structure is provided on a side of the auxiliary conductive structure close to the cathode layer, and a thickness of the etch stop layer is smaller than a thickness of the auxiliary conductive structure.

[0021] In a second aspect, an embodiment of the present invention further provides a display device, including:

[0022] A display panel as described in any one of the above.

[0023] The beneficial effects of the present invention are as follows:

[0024] An embodiment of the present invention provides a display panel and a display device, wherein the display panel includes a base substrate, a cathode layer located in a display area and a non-display area of ​​the base substrate, and an auxiliary cathode structure located in the non-display area; along the direction from the display area to the non-display area, the auxiliary cathode structure includes at least two conductive rings surrounding the display area; an inner conductive ring on the side close to the display area of ​​the at least two conductive rings is coupled to the cathode layer, and the inner conductive ring is arranged around the display area; an outer conductive ring on the side away from the display area of ​​the at least two conductive rings is coupled to a corresponding binding electrode located in a binding area of ​​the base substrate through two oppositely arranged terminals, and receives a driving signal from a driving chip in the binding area through the two terminals; two adjacent conductive rings of the at least two conductive rings are coupled through a lap joint, and the resistance value of the lap joint is greater than the resistance value of the inner conductive ring. That is to say, at least two conductive rings surrounding the display area are provided in the non-display area, and the two adjacent conductive rings are coupled via an overlapping portion having a resistance value greater than that of the inner conductive ring, thereby ensuring that most of the voltage difference of the driving signal provided by the driving chip falls in the area where the overlapping portion is located, thereby improving the voltage uniformity reaching the inner conductive ring, correspondingly reducing the current difference of the cathode layer entering the display area, and ensuring the uniformity of brightness within the surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of a top view of a micro-display product in related art;

[0026] Figure 2 For the Figure 1 A schematic diagram of one of the cross-sectional structures in the direction indicated by MM;

[0027] Figure 3 To adopt Figure 2 A schematic diagram showing one of the simulation results for the in-plane uniformity of a micro-display product larger than 1.5 inches with the structure shown;

[0028] Figure 4 A schematic diagram of a top view of a display panel provided by an embodiment of the present invention;

[0029] Figure 5 For the Figure 4 A schematic diagram of one of the cross-sectional structures in the direction indicated by NN;

[0030] Figure 6 A schematic diagram of a top view of a display panel provided by an embodiment of the present invention;

[0031] Figure 7 A schematic diagram of a top view of a display panel provided by an embodiment of the present invention;

[0032] Figure 8 for Figure 4 A schematic diagram of one of the top-down structures of the middle area Q;

[0033] Figure 9 For the Figure 4 A schematic diagram of one of the cross-sectional structures in the direction indicated by NN;

[0034] Figure 10 A schematic top view of a portion of a display panel provided by an embodiment of the present invention;

[0035] Figure 11 for Figure 2 Schematic diagram of simulation results of the cathode layer sheet resistance and in-plane uniformity of the display panel shown;

[0036] Figure 12 for Figure 2 The optical simulation diagram of one of the display panel cathode layer thicknesses is set to 1000 angstroms, 2000 angstroms and 4000 angstroms respectively;

[0037] Figure 13 for Figure 9 A schematic diagram of one of the simulation results when the cathode layer thickness of the display panel is 4000 angstroms and the ratio of the resistance value of the bonding plate to the resistance value of the inner conductive ring is greater than 1000:1;

[0038] Figure 14 For the Figure 4 A schematic diagram of one of the cross-sectional structures in the direction indicated by NN;

[0039] Figure 15 For the Figure 4 A schematic diagram of one of the cross-sectional structures in the direction indicated by NN;

[0040] Figure 16 A flow chart of a method for manufacturing a display panel provided by an embodiment of the present invention;

[0041] Figure 17 For Figure 16 One of the method flow charts after step S102 in .

[0042] Description of reference numerals:

[0043] 01- auxiliary cathode ring; 02- cathode; 03- anode; 10- substrate; A- display area; B- non-display area; 20- cathode layer; 30- auxiliary cathode structure; 40- at least two conductive rings; 401- inner conductive ring; 402- outer conductive ring; 400- anode layer; C- binding area; 50- binding electrode; 60- overlapping portion; 600- sub- overlapping unit; 70- light-emitting device; 700- light-emitting layer; 80- auxiliary conductive structure; 800- first opening; 90- pixel definition layer; 900- second opening; 81- etching stop layer. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. And in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] Unless otherwise defined, technical or scientific terms used in this invention shall have the same general meaning as those generally understood by persons skilled in the art in the art to which this invention pertains. Words such as "include" or "comprise" used in this invention mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0046] It should be noted that the sizes and shapes of the figures in the accompanying drawings do not reflect the actual scale and are only for the purpose of illustrating the present invention. The same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions.

[0047] In related technologies, micro display products often use Figure 1 and Figure 2 The single cathode ring structure shown, wherein Figure 1 This is a schematic diagram of a top view of a micro display product. Figure 2 For the Figure 1 A schematic diagram of a cross-sectional structure in the direction MM shown in FIG, wherein the reference numeral 01 represents an auxiliary cathode ring, the reference numeral 02 represents a cathode, and the reference numeral 03 represents an anode. Figure 3 Shown is the use of Figure 2Schematic diagram of one of the simulation results for in-plane uniformity of a microdisplay product larger than 1.5 inches. LU represents in-plane uniformity, and the corresponding LU for this product is 31.4%. As microdisplay size increases, the cathode current entering the display area becomes more variable, causing IR drop and a decrease in in-plane brightness uniformity.

[0048] In view of this, embodiments of the present invention provide a display panel and a display device for improving in-plane brightness uniformity.

[0049] Combine Figure 4 and Figure 5 As shown, Figure 4 This is a schematic diagram of a top view of a display panel provided by an embodiment of the present invention. Figure 5 For the Figure 4 A schematic diagram of a cross-sectional structure of the display panel in the direction indicated by NN. Specifically, the display panel includes:

[0050] A base substrate 10, a cathode layer 20 located in a display area A and a non-display area B of the base substrate 10, and an auxiliary cathode structure 30 located in the non-display area B;

[0051] Among them, along the direction from the display area A to the non-display area B, the auxiliary cathode structure 30 includes at least two conductive rings 40 surrounding the display area A; the inner conductive ring 401 close to the display area A of the at least two conductive rings 40 is coupled to the cathode layer 20, and the inner conductive ring 401 is arranged around the display area A; the outer conductive ring 402 on the side away from the display area A of the at least two conductive rings 40 is coupled to the corresponding binding electrode 50 located in the binding area C of the base substrate 10 through two oppositely arranged terminals, and receives the driving signal from the driving chip of the binding area C through the two terminals; two adjacent conductive rings of the at least two conductive rings 40 are coupled through a lap joint 60, and the resistance value of the lap joint 60 is greater than the resistance value of the inner conductive ring 401.

[0052] In a specific implementation process, the display panel includes a base substrate 10, which can be a flexible substrate or a rigid substrate, which is not limited here. When the base substrate 10 is a flexible substrate, the material of the flexible substrate can be a polyimide film (PI) or polyethylene terephthalate (PET), etc., which is not limited here. The flexible substrate can be a structure including a single-layer flexible base layer, or a structure including multiple flexible base layers, such as a structure with two flexible base layers, or a structure with three base layers, which is not limited here. In addition, a support layer (Barrier) can be provided between two adjacent flexible base layers.

[0053] The display panel further includes a cathode layer 20 located in the display area A and the non-display area B of the base substrate 10, and an auxiliary cathode structure 30 located in the non-display area B. In addition, the base substrate 10 further includes a binding area C located in the non-display area B and facing away from the display area A. The binding area C is provided with a binding electrode 50 and a driver chip (not shown) coupled to the binding electrode 50. In one exemplary embodiment, as Figure 4 The figure shows one distribution diagram of the display area A, the non-display area B and the binding area C in the base substrate 10. There can be multiple binding electrodes 50, and the specific number of the binding electrodes 50 can be set according to actual application needs, which is not limited here.

[0054] Along the direction from the display area A to the non-display area B, the auxiliary cathode structure 30 includes at least two conductive rings 40 surrounding the display area A. The at least two conductive rings 40 can be two, or three or more. The specific number of the at least two conductive rings 40 can be set according to the actual application needs, and is not limited here. Among them, the material of the cathode layer 20 can be indium zinc oxide (IZO), which can be set according to the actual application needs. In addition, in the display area A, an anode layer 400 is also provided between the cathode layer 20 and the base substrate 10. The at least two conductive rings 40 can be made of the same layer and material as the anode layer 400 in the display area A. Among them, the material of the anode layer 400 can be a high reflectivity and low square resistance material such as aluminum (Al) and silver (Ag); the specific setting of the anode layer 400 can refer to the relevant technology and will not be described in detail here. Figure 4 and Figure 5 The figure shows a case where there are two at least two conductive rings 40, with the direction indicated by arrow X pointing from the display area A to the non-display area B. Among the at least two conductive rings 40, an inner conductive ring 401 located near the display area A is coupled to the cathode layer 20, and the inner conductive ring 401 surrounds the display area. Accordingly, the inner conductive ring 401 forms a closed structure. Among the at least two conductive rings 40, an outer conductive ring 402 located away from the display area A is coupled to corresponding binding electrodes 50 located in the binding area C of the base substrate 10 via two oppositely disposed terminals, and receives a driving signal from a driver chip in the binding area C via the two terminals. Thus, because adjacent two conductive rings in the at least two conductive rings 40 are coupled via the overlapping portion 60, the driving signal from the driver chip can be provided to the cathode layer 20 via the at least two conductive rings 40, thereby ensuring the display performance of the display panel.

[0055] It should be noted that the outer conductive ring 402 of the at least two conductive rings 40 surrounding the display area A includes two terminals disposed opposite each other, and these two terminals are located in the binding area C. Accordingly, the outer conductive ring 402 is essentially a non-enclosed structure. Furthermore, the other conductive rings of the at least two conductive rings 40, excluding the outer conductive ring, are all disposed around the display area A. In a specific implementation, the number of overlapping portions 60 can be set based on the specific number of the at least two conductive rings 40; for example, if there are two at least two conductive rings 40, there can be one corresponding overlapping portion 60; or, for another example, if there are three at least two conductive rings 40, there can be two corresponding overlapping portions 60. Of course, the specific number of overlapping portions 60 is not limited to this. Furthermore, the resistance of the overlapping portion 60 is greater than the resistance of the inner conductive ring 401. The material of the overlapping portion 60 can be a metal oxide. In one exemplary embodiment, the material of the overlapping portion 60 can be indium tin oxide (ITO). ITO has good light transmittance, thus preventing it from affecting the display quality of the display panel. On the other hand, its resistivity is higher than that of common metals, thus ensuring uniform brightness. This ensures that the majority of the voltage difference of the driving signal provided by the driver chip falls within the region where the overlapping portion 60 is located, thereby improving the voltage uniformity reaching the inner conductive ring 401 and correspondingly reducing the current difference entering the display area A from the cathode layer 20, thus ensuring uniform brightness across the surface.

[0056] In an embodiment of the present invention, each connecting portion 60 includes a plurality of sub-connecting units 600 extending in a direction from the display area A to the non-display area B. In one exemplary embodiment, each sub-connecting unit 600 may be arranged in a linear configuration. In another exemplary embodiment, each sub-connecting unit 600 may be arranged in a non-linear configuration.

[0057] In one exemplary embodiment, Figure 6 FIG. 1 shows a schematic top view of a display panel according to an embodiment of the present invention. In this exemplary embodiment, each overlapping portion 60 includes multiple sub-joint units 600 extending from the display area A toward the non-display area B. Each sub-joint unit 600 is arranged in a straight line. The specific number of sub-joint units 600 can be set based on actual application needs and is not limited here.

[0058] In the embodiment of the present invention, still combined with Figure 6 In the exemplary embodiment shown, the at least two conductive rings 40 include two conductive rings, namely the inner conductive ring 401 and the outer conductive ring 402 , and the plurality of sub-bonding units 600 are arranged in sequence between the inner conductive ring 401 and the outer conductive ring 402 .

[0059] In the embodiment of the present invention, the sub-joining units 600 in each joining portion 60 may be arranged in the following manner, but are not limited to the following manner.

[0060] In one exemplary embodiment, the resistance value of each sub-bonding unit 600 is negatively correlated with the distance from the corresponding sub-bonding unit 600 to the binding area C. That is, the farther the sub-bonding unit 600 is from the binding area C, the smaller its corresponding resistance value. Conversely, the closer the sub-bonding unit 600 is to the binding area C, the larger its corresponding resistance value. This ensures uniformity of the drive signal transmission provided by the driver chip at both the near and far ends, thereby avoiding display unevenness caused by differences in RC loading, ensuring display uniformity, and improving display quality.

[0061] In one exemplary embodiment, the width of each sub-bonding unit 600 in a direction intersecting its extension direction is positively correlated with the distance from the corresponding sub-bonding unit 600 to the binding area C. That is, the further the sub-bonding unit 600 is from the binding area C, the greater its width in a direction intersecting its extension direction, and the smaller its corresponding resistance value; conversely, the closer the sub-bonding unit 600 is to the binding area C, the smaller its width in a direction intersecting its extension direction, and the larger its corresponding resistance value. This ensures the uniformity of the drive signal transmission provided by the driver chip at both the near and far ends, thereby avoiding the problem of display unevenness caused by differences in resistance and capacitance loading (RC Loading), ensuring display uniformity, and improving display quality.

[0062] It should be noted that in one exemplary embodiment, when the length of each sub-bonding unit 600 in the extension direction and the width in the direction intersecting the extension direction are the same, the distribution density of the sub-bonding units 600 farther from the binding area C is lower than the distribution density of the sub-bonding units 600 closer to the binding area C. Accordingly, the resistance value of the sub-bonding units 600 farther from the binding area C is lower. In this way, the uniformity of the driving signal transmission provided by the driver chip at the near and far ends is ensured, thereby improving the display uniformity of the display panel.

[0063] In one exemplary embodiment, the orthographic projection of each sub-bonding unit 600 on the base substrate 10 is arranged in a non-linear shape.

[0064] Combine Figure 7 In the exemplary embodiment shown, the plurality of sub-bonding units 600 may be arranged at an equal density between the inner conductive ring 401 and the outer conductive ring 402 .

[0065] Still taking the example of the non-linear orthographic projections of each sub-bonding unit 600 on the base substrate 10, the length of each sub-bonding unit 600 in the extension direction is negatively correlated with the distance from the corresponding sub-bonding unit 600 to the binding area C. In a specific implementation, the length of each sub-bonding unit 600 in the extension direction is negatively correlated with the distance from the corresponding sub-bonding unit 600 to the binding area C. In other words, when the orthographic projections of each sub-bonding unit 600 on the base substrate 10 are non-linear, the further the sub-bonding unit 600 is from the binding area C, the shorter its length in the extension direction, and accordingly, the smaller its corresponding resistance value. This ensures the uniformity of the drive signal transmission provided by the driver chip at both the near and far ends, thereby improving the display uniformity of the display panel.

[0066] Still combined Figure 7 As shown, the orthographic projection of each sub-lapping unit 600 on the base substrate 10 is arranged in a non-linear manner, that is, the orthographic projection of each sub-lapping unit 600 on the base substrate 10 is arranged in a broken line. In one exemplary embodiment, the material of each sub-lapping unit 600 is ITO, and accordingly, its corresponding resistivity is higher than that of metal of general material. In this way, while each sub-lapping unit 600 is arranged in a non-linear manner, the square resistance of each sub-lapping unit 600 is further improved, thereby ensuring brightness uniformity. Of course, the shape of each sub-lapping unit 600 can be set according to actual application needs. Figure 8 Shown Figure 4 A schematic diagram of one of the top-down structures of the middle area Q.

[0067] In an embodiment of the present invention, each overlapping portion 60 is made of the same material as the cathode layer 20, and the thickness of each overlapping portion 60 is less than the thickness of the cathode layer 20. In one exemplary embodiment, the material of each overlapping portion 60 and the cathode layer 20 can both be ITO. Since ITO itself has a relatively high resistivity, it can effectively increase the square resistance of its corresponding sub-lapping unit 600, thereby ensuring the brightness uniformity of the display panel. In addition, the thickness of each overlapping portion 60 can be less than the thickness of the cathode layer 20. When each overlapping portion 60 is made of ITO material with a relatively high resistivity, since the thickness of each overlapping portion 60 is relatively small, the square resistance of its corresponding sub-lapping unit 600 can be further increased, thereby ensuring the brightness uniformity of the display panel.

[0068] In the embodiment of the present invention, still combined with Figure 7As shown, the distribution density of some sub-lap units 600 in the corner area near the display area A is less than the distribution density of some sub-lap units 600 in the non-corner area excluding the corner area near the display area A. In this way, the uniformity of the corner area and the non-corner area of ​​the drive signal transmission provided by the driver chip is guaranteed, and the display uniformity of the display panel is improved. In the specific implementation process, since the distance between the two conductive rings in the corner area is greater than the distance between them in the non-corner area, the brightness uniformity of the display panel is guaranteed by adjusting the distribution density of some sub-lap units 600 in the corner area and the distribution density of some sub-lap units 600 in the non-corner area. It should be noted that the physical parameters of each sub-lap unit such as length, width, distribution density, etc. can be adjusted according to the in-plane brightness uniformity required by the actual application, which will not be described in detail here.

[0069] In the embodiment of the present invention, the ratio of the resistance value of the overlapping portion 60 to the resistance value of the inner conductive ring 401 is greater than 1000:1.

[0070] In a specific implementation, the ratio of the resistance value of the overlap portion 60 to the resistance value of the inner conductive ring 401 is greater than 1000:1 and less than 100,000:1. Accordingly, the resistance value of the overlap portion 60 is much greater than the resistance value of the inner conductive ring 401. In this way, after the overlap portion 60 is coupled to the inner conductive ring 401, the majority of the voltage difference of the drive signal provided by the driver chip falls within the region where the overlap portion 60 is located, thereby improving the voltage uniformity reaching the inner conductive ring 401, correspondingly reducing the current difference of the cathode layer 20 entering the display area A, and ensuring uniform brightness within the surface. In addition, the specific values ​​of the resistance values ​​of the inner conductive ring 401, the overlap portion 60, and the outer conductive ring 402 can be set according to actual application needs and are not limited here.

[0071] In an embodiment of the present invention, the display panel further includes a plurality of light-emitting devices 70 arranged in the display area A, and an auxiliary conductive structure 80 is provided on the side of the cathode layer 20 facing away from the base substrate 10 , and the auxiliary conductive structure 80 has a first opening 800 at each light-emitting device 70 .

[0072] In a specific implementation process, each light emitting device 70 may include at least one of an organic light emitting diode (OLED) and a quantum dot light emitting diode (QLED). The specific number of the plurality of light emitting devices 70 can be set according to actual application needs. In addition, an auxiliary conductive structure 80 is provided on the side of the cathode layer 20 facing away from the base substrate 10, and the auxiliary conductive structure 80 has a first opening 800 at each light emitting device 70. In one exemplary embodiment, as Figure 9 Shown along Figure 4 A schematic diagram of a cross-sectional structure in the direction shown in FIG. In one exemplary embodiment, Figure 10 This is a schematic top view of a portion of a display panel, illustrating the positional relationship between each light-emitting device 70 and the auxiliary conductive structure 80. Each light-emitting device 70 includes a corresponding anode layer 400 and a light-emitting layer 700. It should be noted that the relevant figures only illustrate the arrangement of some of the light-emitting devices 70 in the display panel and do not imply that the display panel must be arranged in this manner. Of course, the number and arrangement of the light-emitting devices 70 can be set according to actual application needs and are not limited here.

[0073] Still combined Figure 9 As shown, the display panel of the embodiment of the present invention also includes a pixel definition layer 90 located on the side of the cathode layer 20 close to the base substrate 10, and having a second opening 900 at each light-emitting device 70; the orthographic projection of the second opening 900 on the base substrate 10 completely falls within the area of ​​the orthographic projection of the first opening 800 on the base substrate 10.

[0074] In a specific implementation process, the display panel further includes a pixel definition layer 90 having a second opening 900 at each light-emitting device 70, wherein the pixel definition layer 90 is located on the side of the cathode layer 20 close to the base substrate 10. Moreover, the orthographic projection of the second opening 900 on the base substrate 10 completely falls within the area of ​​the orthographic projection of the first opening 800 on the base substrate 10. In practical applications, on the one hand, by coupling the auxiliary conductive structure 80 and the cathode layer 20 in parallel, the overall thickness of the cathode layer 20 is increased to a certain extent, thereby increasing the conductivity of the corresponding structure; on the other hand, interference with the light-emitting device 70 is avoided, thereby ensuring the display effect. Still combined with Figure 9 As shown, the pixel definition layer 90 includes a first silicon oxide (SiO) layer, an aluminum oxide (Al2O3) layer, a silicon nitride (SiN) layer, and a second silicon oxide (SiO) layer, which are sequentially disposed away from the base substrate 10. Of course, the relevant film layers of the pixel definition layer 90 can also be arranged according to actual application needs, and this is not limited here.

[0075] The inventors found in actual research that the ideal OLED cross-voltage is 11.2V. However, due to the large size of micro-display products, the in-plane resistance produces IR drop, and the actual cross-voltage within the pixel is insufficient, resulting in a decrease in in-plane uniformity. Figure 11 Shown for Figure 2 The display panel shown is a schematic diagram of the simulation results of the in-plane uniformity when RS is 45ohm / □, 22.5ohm / □, 8.2ohm / □, 4.5ohm / □, and 1ohm / □, respectively, where RS represents the corresponding square resistance of the cathode layer 20, and LU represents the in-plane uniformity. Based on this, the inventors found that the corresponding square resistance of the cathode layer 20 is negatively correlated with the in-plane uniformity. As the corresponding square resistance of the cathode layer 20 decreases, the in-plane uniformity improves. In the specific implementation process, by providing an auxiliary conductive structure 80 on the side of the cathode layer 20 facing away from the base substrate 10, the corresponding square resistance of the cathode layer 20 can be reduced to a certain extent, thereby improving the in-plane uniformity to a certain extent.

[0076] In an embodiment of the present invention, the thickness of the cathode layer 20 is in the range of 2000 angstroms to 6000 angstroms. For example, in one exemplary embodiment, the thickness of the cathode layer 20 is 4000 angstroms.

[0077] The inventors found in actual research that Figure 2 Taking the display panel shown in FIG. 1 as an example, the thickness of the cathode layer 20 is set to 1000 angstroms, 2000 angstroms and 4000 angstroms respectively. The corresponding optical simulation results are as follows: Figure 12 As shown. Combined Figure 12 It can be seen that when the thickness of the cathode layer 20 is 4000 angstroms, the red light emitting devices of the two are comparable to those of the cathode layer 20 with a thickness of 1000 angstroms, and the blue light emitting devices of the two are comparable. The light emitting effect of the former is improved by about 2.5 times compared to the green light emitting device of the latter. Figure 9 In the display panel shown in FIG. 1 , the thickness of the cathode layer 20 is 4000 angstroms, and the ratio of the resistance value of the overlap portion 60 to the resistance value of the inner conductive ring 401 is greater than 1000:1. The corresponding simulation results are shown in FIG. Figure 13 As shown in Figure 2, the in-plane uniformity reached 88.5%. Figure 2 As for the in-plane uniformity of the display panel shown when the thickness of the cathode layer 20 is 1000 angstroms, the in-plane uniformity is greatly improved, thereby ensuring the in-plane brightness uniformity.

[0078] In an embodiment of the present invention, the auxiliary conductive structure 80 may be composed of TiN / Al / TiN, thereby ensuring the structural stability between the auxiliary conductive structure 80 and the cathode layer 20 and further improving the performance of the display panel.

[0079] In one exemplary embodiment, an etch stop layer 81 surrounding the auxiliary conductive structure 80 is provided on a side of the auxiliary conductive structure 80 close to the cathode layer 20 , and the thickness of the etch stop layer 81 is smaller than that of the auxiliary conductive structure 80 .

[0080] In the specific implementation process, Figure 14 Shown along Figure 4 One of the cross-sectional structural diagrams in the direction shown by NN in the figure, specifically, an etch stop layer 81 surrounding the auxiliary conductive structure 80 is provided on the side of the auxiliary conductive structure 80 close to the cathode layer 20, and the thickness of the etch stop layer 81 is less than the thickness of the auxiliary conductive structure 80. The etch stop layer 81 can be an inorganic material such as silicon nitride (SiN) and silicon oxide (SiO). The thickness of the etch stop layer 81 is less than the thickness of the auxiliary conductive structure 80. In this way, while taking into account the brightness uniformity of the display panel, in the process of forming the auxiliary conductive structure 80 on the side of the cathode layer 20 away from the base substrate 10, the risk of chlorine gas damaging the bottom cathode layer 20 material during the etching process is effectively avoided. In an exemplary embodiment, the cathode layer 20 and the auxiliary conductive structure 80 can be connected through a via hole, thereby avoiding damage to the cathode layer 20 material.

[0081] It should be noted that if Figure 15 Shown along Figure 4 The schematic diagram of one of the cross-sectional structures in the direction shown by NN in the figure shows that the display panel provided by the embodiment of the present invention includes, in addition to the film layer structure mentioned above, a thin film encapsulation layer (Thin Film Encapsulation, TFE) located on the side of the cathode layer 20 and the auxiliary conductive structure 80 away from the base substrate 10. The thin film encapsulation layer includes an inorganic layer and an organic layer that are overlapped. It should be noted that no matter what structure of the thin film encapsulation layer, the top layer of the thin film encapsulation layer is set to be an inorganic layer to effectively block water and oxygen, thereby improving the performance of the display panel. The material of the inorganic layer can be at least one of silicon oxide, silicon nitride, and silicon oxynitride, and the material of the organic layer can be an organic material suitable for inkjet printing.

[0082] In one exemplary embodiment, the display panel further includes a polarizer located on the side of the thin film encapsulation layer facing away from the base substrate 10. The polarizer can not only reduce the reflection of the display panel to the external ambient light and improve the user experience, but also avoid the influence of the external ambient light on the organic light-emitting material, thereby ensuring the life of the organic light-emitting material and improving the performance of the display panel. In addition, the display panel further includes a glue layer and a cover plate arranged on the side of the polarizer facing away from the base substrate 10. The glue layer can be an optically clear adhesive (OCA), which ensures the structural stability while ensuring the transparent display of the display panel. The cover plate can not only protect the display panel from damage, but also improve the performance of the display device by providing a coating with specific functions on the cover plate. The coating can be one or more of an anti-glare (AG) protective film layer, an anti-fingerprint (AF), and an anti-ultraviolet (UV) protective film layer, which are not limited here. Of course, other film layers can also be provided according to actual application needs, which can be implemented with reference to relevant technologies and will not be described in detail here.

[0083] In one exemplary embodiment, Figure 15 As shown, the display panel also includes a color filter located on the side of the thin film encapsulation layer away from the base substrate 10. At this time, a color filter on encapsulation (COE) technology can be used. Compared with the thicker polarizer, the display panel is light and thin. In this exemplary embodiment, the display panel also includes an aluminum oxide (Al2O3) layer, a silicon nitride (SiN) layer and a flat layer (PLN) arranged between the thin film encapsulation layer and the color filter, as well as a glue layer and a cover plate (not shown in the figure) arranged on the side of the color filter away from the base substrate 10. The setting method of the glue layer and the cover plate can be specifically implemented with reference to the relevant technology and will not be described in detail here.

[0084] In one of the exemplary embodiments, the display panel also includes a touch structure (Flexible Multi-Layer On Cell, FMLOC) located on the side of the thin film encapsulation layer facing away from the base substrate 10. Accordingly, the film layers of the touch structure can be directly manufactured on the thin film encapsulation layer. Accordingly, the touch structure is set in the film layer structure, so there is no need to set up a touch substrate separately, thereby ensuring the touch function of the display panel while ensuring the lightweight design of the display panel. For the specific setting of the touch structure, reference can be made to the specific implementation in the relevant technology, which will not be described in detail here. Of course, in addition to the film layer structure mentioned above, the display panel may also include other film layer structures, which can be referred to the specific implementation in the relevant technology, which will not be described in detail here.

[0085] Based on the same inventive concept, an embodiment of the present invention further provides a display device, which solves the problem based on a principle similar to that of the aforementioned display panel. Therefore, the implementation of the display device can refer to the implementation of the aforementioned display panel, and the repeated parts will not be repeated.

[0086] In specific implementations, the display device provided by the embodiments of the present invention can be any product or component with a display function, such as a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigation system, or the like. Other essential components of the display device are well understood by those skilled in the art and are not described in detail here, nor should they be construed as limitations of the present invention.

[0087] Based on the same inventive concept, Figure 16 As shown, an embodiment of the present invention further provides a method for manufacturing the display panel as described above, the manufacturing method comprising:

[0088] S101: forming at least two conductive rings surrounding the display area in the non-display area;

[0089] S102: forming a pattern of the overlapping portion on a side of the at least two conductive rings facing away from the base substrate.

[0090] In the specific implementation process, Figure 5 Taking the display panel shown in FIG. 1 as an example, the specific implementation process of steps S101 to S102 is as follows:

[0091] First, an anodic metal coating is performed on the base substrate 10, for example, a whole layer of aluminum film is coated; then, the aluminum film is coated with glue, exposed, and developed, and dry-etched to obtain a pattern of the anode layer 400 located in the display area A, and a pattern of at least two conductive rings 40 located in the non-display area B of the display area A; then, a metal oxide coating is performed on the side of the anode layer 400 and the at least two conductive rings 40 facing away from the base substrate 10, and then, the glue is coated, exposed, and developed, and dry-etched to form a pattern of the overlapping portion 60 on the side of the at least two conductive rings 40 facing away from the base substrate 10.

[0092] In the embodiment of the present invention, Figure 17 As shown, in step S102: after forming the pattern of the overlapping portion on the side of the at least two conductive rings facing away from the base substrate, the method further includes:

[0093] S201: sequentially forming a pixel definition layer having a second opening, a plurality of light-emitting devices, and the cathode layer;

[0094] S202: forming a pattern of an auxiliary conductive structure on a side of the cathode layer away from the base substrate; wherein the auxiliary conductive structure has a first opening at each light-emitting device, and the orthographic projection of the second opening on the base substrate completely falls within the area of ​​the orthographic projection of the first opening on the base substrate.

[0095] In the specific implementation process, the specific implementation process of step S201 to step S202 is as follows:

[0096] After forming a pattern of the overlapping portion 60 on the side of at least two conductive rings 40 facing away from the base substrate 10, a lateral leakage cutoff (LLC) flattening process can be used to form a planarization layer on the side of the overlapping portion 60 facing away from the base substrate 10; then, a SiOx / Al2O3 / SiNx composite film layer is plated on the side of the planarization layer facing away from the base substrate 10. In one exemplary embodiment, SiOx film layers and SiNx film layers can be formed by plasma enhanced chemical vapor deposition (PECVD); Al2O3 film layers can be formed by atomic layer deposition (ALD); then, photoresist is coated on the side of the composite film layer facing away from the base substrate 10 and dry-etched to obtain a pattern of the pixel definition layer 90; accordingly, the pixel definition layer 90 is provided with a second opening 900, and the orthographic projection of the second opening 900 on the base substrate 10 completely falls within the area of ​​the orthographic projection of the first opening 800 on the base substrate 10; then, a plurality of light-emitting devices 70 and a cathode layer 20 are sequentially formed by an evaporation process. In one exemplary embodiment, the thickness of the cathode layer 20 may be 4000 angstroms; then, metal plating is performed on the side of the cathode layer 20 facing away from the base substrate 10, the glue is applied, exposed and developed, and dry etching is performed to form a pattern of the auxiliary conductive structure 80; wherein, the auxiliary conductive structure 80 has a first opening 800 at each light-emitting device 70, and the orthographic projection of the second opening 900 on the base substrate 10 completely falls within the area of ​​the orthographic projection of the first opening 800 on the base substrate 10.

[0097] In one exemplary embodiment, after forming the cathode layer and before forming the auxiliary conductive structure, the method further includes:

[0098] A pattern of an etch stop layer is formed on a side of the cathode layer facing away from the substrate; wherein the thickness of the etch stop layer is less than the thickness of the auxiliary conductive structure.

[0099] In the specific implementation process, after the cathode layer 20 is formed, a whole inorganic layer can be deposited on the side of the cathode layer 20 facing away from the base substrate 10; then, the inorganic layer is coated with photoresist and dry-etched to form a pattern of the etching barrier layer 81; then, a whole metal film layer for preparing the auxiliary conductive structure 80 is plated according to the pattern of the etching barrier layer 81; then, the metal film layer is etched to form the pattern of the auxiliary conductive structure 80.

[0100] In addition, the display panel may further include other film layer structures. The manufacturing process of the relevant film layer structures can be implemented by referring to the techniques in the relevant art, which will not be described in detail here.

[0101] An embodiment of the present invention provides a display panel and a display device, wherein the display panel includes a base substrate 10, a cathode layer 20 located in a display area A and a non-display area B of the base substrate 10, and an auxiliary cathode structure 30 located in the non-display area B; along the direction from the display area A to the non-display area B, the auxiliary cathode structure 30 includes at least two conductive rings 40 surrounding the display area A; an inner conductive ring 401 on the side close to the display area A of the at least two conductive rings 40 is coupled to the cathode layer 20, and the inner conductive ring 401 is arranged around the display area A; an outer conductive ring 402 on the side away from the display area A of the at least two conductive rings 40 is coupled to a corresponding binding electrode 50 located in a binding area C of the base substrate 10 through two oppositely arranged terminals, and receives a driving signal from a driving chip in the binding area C through the two terminals; two adjacent conductive rings of the at least two conductive rings 40 are coupled through a lap joint 60, and the resistance value of the lap joint 60 is greater than the resistance value of the inner conductive ring 401. That is to say, at least two conductive rings 40 are provided in the non-display area B so as to surround the display area A, and the two adjacent conductive rings are coupled via a lap joint 60 having a resistance value greater than that of the inner conductive ring 401, thereby ensuring that most of the voltage difference of the driving signal provided by the driving chip falls within the region where the lap joint 60 is located, thereby improving the voltage uniformity reaching the inner conductive ring 401, and correspondingly reducing the current difference of the cathode layer 20 entering the display area A, thereby ensuring the uniformity of the brightness within the surface.

[0102] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0103] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A display panel, characterized in that: include: A base substrate, a cathode layer located in a display area and a non-display area of ​​the base substrate, and an auxiliary cathode structure located in the non-display area; Wherein, along the direction from the display area to the non-display area, the auxiliary cathode structure includes at least two conductive rings surrounding the display area; an inner conductive ring of the at least two conductive rings, which is closer to the display area, is coupled to the cathode layer, and the inner conductive ring is arranged around the display area; an outer conductive ring of the at least two conductive rings, which is away from the display area, is coupled to corresponding binding electrodes located in the binding area of ​​the substrate through two oppositely arranged terminals, and receives a driving signal from a driving chip in the binding area through the two terminals; two adjacent conductive rings of the at least two conductive rings are coupled through a lap joint, and the resistance value of the lap joint is greater than the resistance value of the inner conductive ring; Wherein, each overlapping portion includes a plurality of sub-overlapping units extending in a direction from the display area to the non-display area.

2. The display panel according to claim 1, wherein The at least two conductive rings include two conductive rings including the inner conductive ring and the outer conductive ring, and the inner conductive ring and the outer conductive ring include the plurality of sub-bridge units arranged in sequence.

3. The display panel according to claim 2, wherein: The resistance value of each sub-bonding unit is negatively correlated with the distance between the corresponding sub-bonding unit and the binding area.

4. The display panel according to claim 3, wherein: The width of each sub-joint unit in a direction intersecting the extending direction is positively correlated with the distance from the corresponding sub-joint unit to the binding area.

5. The display panel according to claim 4, wherein: The orthographic projections of the sub-joining units on the base substrate are arranged in a non-linear shape.

6. The display panel according to claim 5, wherein: The length of each sub-joint unit in the extension direction is negatively correlated with the distance from the corresponding sub-joint unit to the binding area.

7. The display panel according to any one of claims 1 to 6, wherein: The overlapping portions are made of the same material as the cathode layer, and the thickness of the overlapping portions is smaller than the thickness of the cathode layer.

8. The display panel according to claim 7, wherein: The distribution density of some of the sub-overlapping units near the corner areas of the display area is smaller than the distribution density of some of the sub-overlapping units near the non-corner areas of the display area except the corner areas.

9. The display panel according to claim 8, wherein: The ratio of the resistance value of the overlapping portion to the resistance value of the inner conductive ring is greater than 1000:

1.

10. The display panel according to claim 9, wherein: It also includes a plurality of light-emitting devices arranged in the display area, and an auxiliary conductive structure is provided on the side of the cathode layer away from the base substrate, and the auxiliary conductive structure has a first opening at each light-emitting device.

11. The display panel according to claim 10, wherein: It also includes a pixel definition layer located on the side of the cathode layer close to the base substrate and having a second opening at each light-emitting device; the orthographic projection of the second opening on the base substrate completely falls within the area of ​​the orthographic projection of the first opening on the base substrate.

12. The display panel according to claim 11, wherein: The thickness of the cathode layer ranges from 2000 angstroms to 6000 angstroms.

13. The display panel according to claim 12, wherein: The auxiliary conductive structure is composed of TiN / Al / TiN.

14. The display panel according to claim 13, wherein: An etch stop layer surrounding the auxiliary conductive structure is provided on a side of the auxiliary conductive structure close to the cathode layer, and the thickness of the etch stop layer is smaller than the thickness of the auxiliary conductive structure.

15. A display device, characterized in that: include: The display panel according to any one of claims 1 to 14.

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