Display panel and preparation method thereof

Abstract

The invention discloses a display panel and a preparation method thereof, and belongs to the technical field of OLED display. The display comprises a substrate, a driving circuit, an anode, a light-emitting layer, a cathode, a pixel definition layer and a filter layer. The core is that the driving circuit provides multiple paths of independent negative voltages, and cathodes of pixels with the same light emitting color are connected in parallel and share one path of negative voltage, so that a color separation independent power supply framework is formed; meanwhile, cathodes of pixels of the same color are connected in series and conducted in the Y direction by means of a specific patterned pixel definition layer, and connection between pixels of different colors is cut off in the X direction. According to the design, the red, green and blue pixels can work under different optimal cathode voltages, so that the efficiency difference of materials can be compensated in a targeted manner, the service life of a screen is prolonged, the power consumption of a system is reduced, and the display brightness and the color gamut are effectively improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of OLED display, and particularly relates to a display panel and a preparation method thereof, and is particularly suitable for the field of high-resolution micro display. BACKGROUND

[0002] The organic light-emitting diode micro display (Micro OLED) has great advantages in the near-eye display field due to high color gamut, low power consumption and heat generation, high resolution, high contrast, high refresh rate, simple structure, small size, good portability and the like. At present, a scheme of white light OLED plus color filter (CF) is mainly used, and OLED generally adopts a common cathode scheme, that is, all pixels of red, green and blue share one layer of cathode and one potential, for example, all use 0V, -0.5V, -1V or -2V and the like.

[0003] The near-eye display terminal has high requirements on the performance of Micro OLED, and needs high brightness, high color gamut, long service life and low power consumption, but the current Micro OLED has the problem of uneven service life attenuation, which limits its application in the near-eye display industry. SUMMARY

[0004] According to a first aspect of an embodiment of the present application, a display panel is provided, comprising pixel units arranged in an array.

[0005] In some embodiments, the pixel units comprise pixels of at least three different colors.

[0006] Further, the arrangement of the pixels comprises the same column being the same color; or, the pixels of the same color are arranged in columns in the column direction, and the pixels of different colors are arranged in an interlaced manner in the horizontal and vertical directions; or, the columns of pixels of a single color and the columns of pixels of different colors are arranged alternately in the row direction.

[0007] In some embodiments, the cathode wires of the pixels of the same color in at least two pixel units are connected.

[0008] Further, the cathode wires of the pixels of the same color in all pixel units are connected; or, the cathodes of each column of pixels are connected in series with each other and connected to a cathode connection area, and the cathode wires of the pixels of different columns are not connected; or, the cathode wires of the pixels of the same color in the pixel units in a certain region are connected, and the cathode wires of the pixel units outside the region and the pixel units in the region are not connected.

[0009] In some embodiments, the display panel comprises: an anode, a light-emitting layer, a cathode and a pixel definition layer arranged in a stack on one side of a substrate. The anode is arranged on the side of the light-emitting layer close to the substrate. The pixel definition layer is arranged between any two adjacent pixels in the same pixel unit.

[0010] Further, the pixel definition layer comprises an undercut structure, which presents a wide-top-narrow-bottom shape in a cross section perpendicular to the substrate. Alternatively, the pixel definition layer comprises a T-shaped structure, the sidewall of which in a cross section perpendicular to the substrate is a vertical straight line.

[0011] In some embodiments, the pattern of the pixel definition layer comprises a pixel definition layer opening region formed in the column direction, and the cathodes of the pixels of the same color in the same column are connected through the pixel definition layer opening region. Alternatively, the pattern of the pixel definition layer comprises an opening above the anode, and the cathodes of the pixels of the same color in the same column are connected through a lateral groove.

[0012] According to a second aspect of the embodiments of the present application, a method for manufacturing the display panel is provided, comprising: providing a substrate with a driving circuit; forming anodes of pixel units arranged in an array on the substrate; forming an undercut or T-shaped pixel definition layer above the anodes; sequentially depositing a light-emitting layer, a cathode, an encapsulation layer and a filter layer; the cathodes are connected through the patterned undercut or T-shaped pixel definition layer.

[0013] In some embodiments, the undercut pixel definition layer is a single-layer structure, and the wide-top-narrow-bottom structure is etched by a method of physical etching first and then chemical etching.

[0014] In some embodiments, the sidewall of the undercut pixel definition layer has an inclination angle of 60° to 85°.

[0015] In some embodiments, the T-shaped pixel definition layer is a multi-layer structure, and the T-shaped structure is etched by etching the top layer first and then etching the bottom layer.

[0016] The undercut or T-shaped pixel definition layer comprises a single-layer or multi-layer structure. The present application has the following advantages: 1、The present application provides independently adjustable cathode negative pressure for pixels of different colors by adopting flexible cathode wiring schemes such as full-screen same-color common cathode, column or row same-color common cathode and sub-regional same-color common cathode. This enables red, green and blue pixels to work at the optimal voltage tailored for their material characteristics, thereby precisely compensating for the inherent differences such as low efficiency and rapid decay of blue pixels. Not only does this effectively alleviate the uneven life decay problem between pixels of different colors, significantly prolonging the overall service life of the screen, but also helps to improve the uniformity of display brightness and expand the color gamut.

[0017] 2、The present application can precisely realize the cathode series connection of same-color pixels in the Y direction and electrical isolation in the X direction by designing a matching pixel definition layer lithography pattern, and at the same time, the shape and position characteristics of different color pixels in a specific arrangement are designed for targeted connection, optimizing the current distribution of the cathode and further ensuring the uniformity of display brightness and chrominance under various complex arrangements. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a cathode communication schematic diagram of a first display panel of an embodiment of the present application; Figure 2 is a cathode communication schematic diagram of a second display panel of an embodiment of the present application; Figure 3 is a cathode communication schematic diagram of a third display panel of an embodiment of the present application; Figure 4 is a cathode communication schematic diagram of a fourth display panel of an embodiment of the present application; Figure 5 is a cathode communication schematic diagram of a fifth display panel of an embodiment of the present application; Figure 6 is a cathode communication schematic diagram of a sixth display panel of an embodiment of the present application; Figure 7 is a cathode communication schematic diagram of a seventh display panel of an embodiment of the present application; Figure 8 is a structure diagram of a display panel of an embodiment of the present application; Figure 9 is a cross-sectional view of a display panel of an embodiment of the present application in the Y direction; Figure 10 is a cross-sectional view of a display panel of an embodiment of the present application in the X direction; Figure 11 is a schematic diagram of a pixel arrangement scheme of an embodiment of the present application; Figure 12 is a schematic diagram of another pixel arrangement scheme of an embodiment of the present application; Figure 13 is a preparation flowchart of a display panel of an embodiment of the present application; Figure 14 is a structure diagram of an undercut pixel definition layer of an embodiment of the present application; Figure 15 is a structure diagram of a T-shaped pixel definition layer of an embodiment of the present application; Figure 16 is a patterning schematic diagram of a pixel definition layer of an embodiment of the present application; Figure 17 is a patterning schematic diagram of another pixel definition layer of an embodiment of the present application.

[0019] Reference signs: the first display panel 100, the second display panel 200, the third display panel 300, the fourth display panel 400, the fifth display panel 500, the sixth display panel 600, the seventh display panel 700, a pixel arrangement scheme 800, another pixel arrangement scheme 900, a pixel unit 110, a cathode communication region 120, a pixel definition layer opening region 130, a lateral slot 140, a substrate 1, a driving circuit 2, an anode 3, a pixel definition layer 4, a pixel definition layer one 41, a pixel definition layer two 42, a light-emitting layer 5, a cathode 6, an encapsulation layer 7, a color filter layer 8. DETAILED DESCRIPTION

[0020] The exemplary embodiments will be described in detail herein below with reference to the drawings. When the following description refers to the drawings, identical numbers on different drawings represent the same or similar elements unless otherwise indicated. The following exemplary embodiments described in the exemplary embodiments do not represent all the implementations consistent with the present application. Instead, they are merely examples of apparatuses and methods consistent with some aspects of the present application as detailed in the appended claims.

[0021] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. Unless otherwise defined, the technical or scientific terms used in this application should be understood in their ordinary sense by one of ordinary skill in the art to which this invention pertains. The words “a” or “one” and similar terms used in this application specification and claims do not indicate a limitation of quantity, but rather indicate the presence of at least one. “A plurality” means two or more. The words “comprising” or “including” and similar terms mean that the element or object preceding “comprising” or “including” covers the element or object listed following “comprising” or “including” and its equivalents, and does not exclude other elements or objects. The words “connected” or “linked” and similar terms are not limited to physical or mechanical connections and can include electrical connections, whether direct or indirect. The words “above” and / or “below” and similar terms are for ease of description only and are not limited to a location or spatial orientation. The singular forms “a,” “the,” and “the” used in this application specification and appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0022] The concept of this invention includes: Currently, the main approach uses white OLEDs with color filters (CF). OLEDs generally employ a common cathode design, where all red, green, and blue pixels share a single cathode layer and a common voltage, such as 0V, -0.5V, -1V, or -2V. However, sharing a single cathode layer presents several problems. First, the lifespan of a common cathode OLED is unevenly degraded: the blue organic material in the OLED degrades significantly faster than the red and green materials. In a common cathode design, all pixels share the same cathode voltage, making it impossible to individually optimize the driving conditions of the blue pixels. This leads to color shifts in the screen after long-term use, such as a yellowish or reddish tint. Furthermore, when displaying static images for extended periods, excessive wear and tear on the blue pixels can create permanent image retention. The common cathode structure, unable to dynamically adjust the voltage of each pixel, further amplifies this problem.

[0023] Secondly, the brightness of common cathode OLEDs is limited: In order to prevent accelerated aging under high brightness, OLEDs will enable an automatic brightness limiting mechanism. Because the voltage distribution of the common cathode solution is fixed, the overall brightness will be forcibly reduced when displaying a large area of ​​white or bright screen, which will affect the viewing experience.

[0024] Finally, common cathode OLEDs consume a lot of power at high brightness: blue pixels require more current at high brightness, and the common cathode structure forces red and green pixels to also bear the same voltage, resulting in additional power consumption and shortening the device's battery life.

[0025] To address the aforementioned issues, this application provides a display panel and a method for manufacturing the same, comprising pixel units arranged in an array; The pixel unit includes at least three different colors of pixels; The cathode wires of the pixels of the same color in the same column or the pixels of the same color in at least two pixel units are connected in communication.

[0026] The application solves the problems of uneven Micro OLED life attenuation, screen burning, low brightness and color gamut difference by using different cathode wire schemes, color separation independent cathode control schemes and different colors of pixels using different cathode voltages.

[0027] The display panel and the preparation method thereof provided in the application will be described in detail below. Figures 1 to 13 The display panel and the preparation method thereof provided in the application will be described in detail below.

[0028] As shown in the accompanying drawings, Figure 1 The application provides a first display panel 100 including pixel units 110 arranged in an array; The pixel units 110 include red, green and blue pixels of three different colors; the red pixels 111, the green pixels 112 and the blue pixels 113 are arranged in an array in the column (or row) direction; the colors of the pixels in the same column (or row) are all the same.

[0029] In the embodiment, the pixels of the same color in the same column (or row) and the pixels of the same color in different columns (or rows) are connected together by connecting the metal layers of the cathode communication areas 120 in parallel, thereby being commonly connected to the same negative voltage source and forming a full-screen common cathode display panel.

[0030] In the embodiment, the color types of the pixels in the pixel units 110 can be more than three, and the embodiment is exemplified by red, green and blue pixels of three different colors.

[0031] In the embodiment, the number of the negative voltage sources is three, and the negative voltage sources are connected to the cathodes of the red, green and blue pixels of different colors, respectively. Therefore, all the red pixels 111 of the display panel 100 in the embodiment share one negative voltage, all the green pixels 112 share one negative voltage, and all the blue pixels 113 share one negative voltage.

[0032] Further, the number of the negative voltage sources is consistent with the number of the color types of the pixels in the pixel units 110 in the embodiment, and therefore, the number of the negative voltage sources can also be more than three.

[0033] The negative voltage source here provides independent and adjustable negative voltages to the cathodes of pixels of different colors according to product functional requirements. By using different cathode voltages for red, green, and blue pixels, luminous efficiency and lifespan are optimized. It allows for individual optimization of the cathode voltage for each color, reducing the overdrive pressure of high-voltage sub-pixels (such as blue pixel 113) and extending their lifespan. It also prevents low-voltage sub-pixels (such as red pixel 111) from being forced to have their voltage increased due to sharing a cathode, thus reducing efficiency loss. By dynamically adjusting the cathode voltage, it can compensate for the differences in aging rates of different color pixels (such as blue decaying faster) and maintain display uniformity.

[0034] like Figure 2 As shown, this application provides a second type of display panel 200, including pixel units 110 arranged in an array; The pixel unit 110 includes pixels of three different colors: red, green, and blue.

[0035] In this embodiment, the pixel unit 110 is divided into two parts, left and right. The left part includes red pixels 111 and blue pixels 113, which are arranged alternately. The right part includes a single green pixel 112.

[0036] In this embodiment, the pixel unit 110 can have three or more color types. This embodiment uses red, green and blue pixels as examples. The alternating arrangement of pixels in this embodiment is illustrated by red pixel 111 and blue pixel 113. Any alternating arrangement of two types of pixels in the column (or row) direction is a derivative scheme of this embodiment.

[0037] In this embodiment, there are three negative pressure sources, which are respectively connected to the cathodes of red, green and blue pixels of different colors. Therefore, in this embodiment, all red pixels 111 of the display panel 200 share one negative pressure source, all green pixels 112 share one negative pressure source, and all blue pixels 113 share one negative pressure source.

[0038] Furthermore, the number of negative pressure sources is consistent with the number of color types of pixels in pixel unit 110 in this embodiment, so the number of negative pressure sources can also be three or more.

[0039] In this embodiment, alternating red pixels 111 located in the same column (or row) are connected by a lateral conductive medium to achieve common connection to the same negative pressure source 3; blue pixels 113 are also connected by a lateral conductive medium to achieve common connection to the same negative pressure source 1; the metal layers of the cathode connection regions 120 of green pixels 112 located in the same column (or row) are connected in parallel to achieve common connection to the same negative pressure source 2.

[0040] like Figure 3As shown, this application provides a third type of display panel 300, including pixel units 110 arranged in an array; The pixel unit 110 includes pixels of three different colors: red, green, and blue.

[0041] In this embodiment, the red pixel 111, green pixel 112 and blue pixel 113 in pixel unit 110 are arranged alternately in the column (or row) direction.

[0042] In this embodiment, the pixel unit 110 can have three or more color types. This embodiment uses red, green and blue pixels as examples. This embodiment uses an alternating arrangement of red pixel 111, green pixel 112 and blue pixel 113 as an example. Any alternating arrangement of the three types of pixels in the column (or row) direction is a derivative scheme of this embodiment.

[0043] In this embodiment, the red pixels 111 in the alternating arrangement are connected by a lateral conductive medium to achieve a common connection to the same negative pressure source 3; the green pixels 112 in the alternating arrangement are connected by a lateral conductive medium to achieve a common connection to the same negative pressure source 2; and the blue pixels 113 in the alternating arrangement are connected by a lateral conductive medium to achieve a common connection to the same negative pressure source 1.

[0044] In this embodiment, there are three negative pressure sources, which are respectively connected to the cathodes of red, green and blue pixels of different colors. Therefore, in this embodiment, all red pixels 111 of the display panel 300 share one negative pressure source, all green pixels 112 share one negative pressure source, and all blue pixels 113 share one negative pressure source.

[0045] Furthermore, the number of negative pressure sources is consistent with the number of color types of pixels in pixel unit 110 in this embodiment, so the number of negative pressure sources can also be three or more.

[0046] like Figure 4 As shown, this application provides a fourth type of display panel 400, including pixel units 110 arranged in an array; The pixel unit 110 includes pixels of three different colors: red, green, and blue. Pixels in the same column (or row) have the same color, and the cathode connecting areas 120 of pixels of the same color in different columns (or rows) are connected to different negative pressure sources to form a display panel in which columns or rows share a common cathode.

[0047] In this embodiment, the pixel unit can have three or more color types. This embodiment uses red, green and blue pixels as an example.

[0048] Furthermore, in this embodiment, pixels of the same color in each column (or row) are connected to a single negative pressure source.

[0049] The display panel 400 here refines the global control of the entire screen sharing a common cathode for the same color into local control by column or row. Specifically, it connects the cathodes of all pixels of the same color in each column (or row) in series through the metal layer of the cathode connection area 120, and connects them together to an independent negative voltage source. The red pixels 111, green pixels 112, and blue pixels 113 in each column (or row) are each driven by an independent negative voltage source, thereby achieving independent and further precise control of the voltage of pixels of the same color in the column (or row) dimension.

[0050] like Figure 5 As shown, this application provides a fifth type of display panel 500, including pixel units 110 arranged in an array; The pixel unit 110 includes pixels of three different colors: red, green, and blue.

[0051] In this embodiment, the pixel unit 110 is divided into two parts, left and right. The left part includes red pixels 111 and blue pixels 113, which are arranged alternately. The right part includes a single green pixel 112.

[0052] In this embodiment, alternating red pixels 111 located in the same column (or row) are connected by a lateral conductive medium to achieve common connection to the same negative pressure source 3; blue pixels 113 are also connected by a lateral conductive medium to achieve common connection to the same negative pressure source 1; the metal layers of the cathode connection regions 120 of green pixels 112 located in the same column (or row) are connected in parallel to achieve common connection to the same negative pressure source 2.

[0053] Furthermore, the alternating red pixels 111 located in other columns (or rows) are connected by a lateral conductive medium to achieve a common connection to the same negative pressure source 4; the blue pixels 113 are also connected by a lateral conductive medium to achieve a common connection to the same negative pressure source 6; the metal layers of the cathode connection regions 120 of the green pixels 112 located in other columns (or rows) are connected together to achieve a common connection to the same negative pressure source 5.

[0054] like Figure 6 As shown, this application provides a sixth type of display panel 600, including pixel units 110 arranged in an array; The pixel unit 110 includes pixels of three different colors: red, green, and blue.

[0055] In this embodiment, the red pixel 111, green pixel 112 and blue pixel 113 in pixel unit 110 are arranged alternately in the column (or row) direction.

[0056] In this embodiment, the red pixels 111 in the alternating arrangement of pixels in the same column are connected by a lateral conductive medium to achieve common connection to the same negative pressure source 3; the green pixels 112 in the alternating arrangement of pixels in the same column are connected by a lateral conductive medium to achieve common connection to the same negative pressure source 2; and the blue pixels 113 in the alternating arrangement of pixels in the same column are connected by a lateral conductive medium to achieve common connection to the same negative pressure source 3.

[0057] In this embodiment, the red pixels 111, green pixels 112, and blue pixels 113 in the other columns are connected to other negative pressure sources in the same manner as described above.

[0058] like Figure 7 As shown, this application provides a seventh type of display panel 700, including pixel units 110 arranged in an array; The pixel unit 110 includes pixels of three different colors: red, green, and blue. Pixels of the same color in the same column (or row) within a certain area and pixels of the same color in different columns (or rows) are connected together in parallel by the metal layer of the cathode connecting region 120. Outside of the designated area, pixels of the same color are connected to another negative pressure source, forming a display panel with a shared cathode for each area of ​​the same color.

[0059] The pixel arrangement within a certain area in this embodiment includes all cases from display panel 100 to display panel 600.

[0060] In this embodiment, the pixel unit can have three or more color types. This embodiment uses red, green and blue pixels as an example.

[0061] The display panel 300 here adopts a scheme of dividing the screen into several independently controlled sub-areas and providing a dedicated cathode negative voltage for each group of pixels of the same color in each area.

[0062] Through the area control module integrated in the drive circuit, it is possible to monitor in real time or, based on a preset model, accurately compensate for inconsistent brightness decay or display abnormalities in different areas caused by manufacturing process deviations, differences in usage time, or uneven temperature distribution.

[0063] In this embodiment, the display panel 300 expands the product's debugging dimensions and compensation accuracy. For the blue pixel area in the center of the screen that decays first due to frequent use, a more negative cathode voltage can be applied independently to enhance its electron injection, thereby effectively compensating for brightness and suppressing image retention. For areas with lighter edge decay or inherent Mura defects, a specific voltage can be applied for local correction, while avoiding unnecessary overdriving of other normal areas. This improves overall visual consistency, optimizes power consumption, and further extends service life.

[0064] like Figure 8 As shown, this application provides a structure for a display panel 100. Further explanation of the display panel 100 is provided below. The display panel 100 specifically includes: An anode 3, a light-emitting layer 5, a cathode 6, a pixel definition layer 4, an encapsulation layer 7, and a color filter layer 8 are stacked on one side of the substrate 1; the anode 3 is disposed on the side of the light-emitting layer 5 close to the substrate 1; the pixel definition layer 4 is disposed between any two adjacent pixels in the same pixel unit; and the substrate 1 contains a driving circuit 2.

[0065] To better understand the structure of this application, a cross-sectional view of the structure of a display panel 100 in the Y direction is provided, as shown below. Figure 9 As shown, in the cross-sectional view along the Y direction, there is no pixel definition layer 4 structure. The cathode 6 and light-emitting layer 5 of pixels of the same color are connected in series to achieve pixel color separation while maintaining conductivity. This application also provides a cross-sectional view of the structure of a display panel 100 along the X direction, as shown... Figure 10 As shown, the pixel definition layer 4 can cut off the light-emitting layer 5 and the cathode 6 in a certain direction to prevent the light-emitting layer 5 and the cathode 6 of different color pixels from being connected together.

[0066] Furthermore, the structure of the display panel 200 to the display panel 600 in this embodiment is the same as that of the display panel 100 described above, except that the wiring connection method of the cathode 6 is different.

[0067] Furthermore, such as Figure 11 As shown, this application provides a pixel arrangement scheme 800, including pixels of three different colors: red, green, and blue; Pixels of the same color are arranged in columns (or rows), while pixels of different colors are arranged alternately in both the horizontal and vertical directions.

[0068] In this embodiment, the pixel can have three or more colors. This embodiment uses red, green and blue pixels as an example.

[0069] One pixel arrangement scheme 800 here significantly improves visual perception resolution by arranging red pixels 111, green pixels 112, and blue pixels 113 in a triangular structure. It achieves a more delicate imaging effect with the same number of physical pixels, effectively suppresses screen graininess and flicker, and significantly optimizes the display of diagonal lines and curves, reducing jagged edges, thereby bringing a smoother color transition and a higher overall display quality visual experience.

[0070] Furthermore, such as Figure 12 As shown, another pixel arrangement scheme 900 is provided, which includes pixels of three different colors: red, green, and blue. Red pixels 111 and blue pixels 113 are arranged in a column, and red pixels 111 and blue pixels 113 are arranged alternately in the column (or row) direction. Green pixels 112 are arranged in the same color in the column (or row) direction. Green pixels 112 are in a separate column, and the columns (or rows) of red pixels 111 and blue pixels 113 are arranged alternately with the columns (or rows) of green pixels 112.

[0071] Furthermore, the width of the green pixel 112 can be set to a different width than that of the red pixel 111 and the blue pixel 113.

[0072] In this embodiment, the pixel can have three or more colors. This embodiment uses red, green and blue pixels as an example.

[0073] Another pixel arrangement scheme 900 here reduces the total number of pixels per unit area by having adjacent pixels share some pixels, thereby significantly improving the manufacturing yield of the screen and reducing costs. At the same time, this scheme achieves higher visual perception resolution through a unique pixel arrangement, distributing the light load to multiple green pixels 112, thereby effectively delaying material aging and extending the overall lifespan of the screen.

[0074] This application provides a method for manufacturing a display panel, such as... Figure 13 As shown, it includes: Provide a substrate with driving circuitry; An anode is formed on the substrate by forming an array of pixel units; An undercut or T-shaped pixel definition layer is formed above the anode; The light-emitting layer, cathode, encapsulation layer, and filter layer are formed sequentially. The cathode forms interconnected wiring through the patterned undercut or T-shaped pixel definition layer.

[0075] In this embodiment, the substrate 1 contains a driving circuit 2. The anode 3 is formed by vapor deposition of anode metal and photolithography etching to form an anode light-emitting area. The independent anodes 3 are arranged in an array above the driving circuit 2 of the substrate 1 to ensure that they are connected to the driving circuit 2.

[0076] In this embodiment, a pixel definition layer 4 with an undercut structure or a T-shaped structure is formed by vapor deposition and etching of metal on the basis of the independent anode 3.

[0077] In this embodiment, the light-emitting layer 5, the cathode 6, the encapsulation layer 7, and the color filter layer 8 are sequentially evaporated or deposited on the pixel definition layer 4 to finally obtain the display panel 100.

[0078] In this embodiment, the structure of the pixel definition layer is further explained using a single-layer undercut pixel definition layer and a double-layer T-shaped pixel definition layer as examples.

[0079] like Figure 14 As shown, the bottom-cut pixel definition layer is a single-layer structure, and the bottom-cut structure has a shape that is wider at the top and narrower at the bottom in a cross section perpendicular to the substrate; By first physical etching and then chemical etching, a structure that is wider at the top and narrower at the bottom is etched out. The sidewall tilt angle of the pixel definition layer of the undercut structure is 60° to 85°.

[0080] In this embodiment, as Figure 15 As shown, the T-shaped pixel definition layer is a double-layer structure, including pixel definition layer one 41 and pixel definition layer two 42. On the cross-section perpendicular to the substrate, the sidewalls of the T-shaped structure are vertical straight lines. The T-shaped structure is created by first etching the top layer and then etching the bottom layer.

[0081] Furthermore, the undercut or T-shaped pixel definition layer can adopt a single-layer structure or a double-layer structure, or the number of pixel definition layers can be set to three or more.

[0082] In the fabrication process of the display panel 100, the aforementioned undercut or T-shaped pixel definition layer needs to be realized through photolithography and etching processes. The photolithography step requires the use of a mask to define the pattern path. Therefore, in this embodiment, a method for fabricating a display panel includes the aforementioned photolithography method for the undercut or T-shaped pixel definition layer.

[0083] like Figure 16 As shown, a method for patterning a pixel definition layer 4 is provided. The pattern of the pixel definition layer 4 includes forming a through pixel definition layer opening region 130 in the column direction. The cathodes 6 of pixels of the same color in the same column are connected through the pixel definition layer opening region 130. After photolithography, the pixel definition layer 4 above the pixel definition layer opening region 130 is removed, and the pixel definition layer 4 that is not removed by photolithography forms a pattern as shown in the diagram.Figure 8 The pattern shown is a cut-off pattern of the light-emitting layer 5 and the cathode 6.

[0084] like Figure 17 As shown, another method for patterning a pixel definition layer is provided. The pattern of the pixel definition layer 4 includes an opening above the anode 3. Due to the alternating arrangement of red and blue pixels in the pixel arrangement scheme 900, pixels of the same color located in the red and blue pixel columns are connected through lateral slots 140; while green pixels are all of the same color in the column direction and are connected by a through-hole pixel definition layer opening. After photolithography, the pixel definition layer above the opening is removed. After the evaporation of the light-emitting layer and the cathode, cathodes of the same color are interconnected and finally connected to different negative pressure sources to achieve the display panel effect of this application.

[0085] As is known from common technical knowledge, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative and not exhaustive. All modifications within the scope of this invention or its equivalents are included in this invention.

Claims

1. A display panel, characterized in that, Including pixel units arranged in an array; The pixel unit includes pixels of at least three different colors; Cathode wiring of pixels of the same color located in the same column or pixels of the same color in at least two pixel units is connected.

2. The display panel according to claim 1, characterized in that, The cathode wiring of pixels of different colors is not interconnected.

3. The display panel according to claim 1, characterized in that, The display panel includes An anode, a light-emitting layer, a cathode, and a pixel definition layer are stacked on one side of the substrate; The anode is disposed on the side of the light-emitting layer closest to the substrate; The pixel definition layer is set between any two adjacent pixels in the same pixel unit.

4. The display panel according to claim 1, characterized in that, The pixel definition layer includes an undercut structure, which has a shape that is wider at the top and narrower at the bottom in a cross section perpendicular to the substrate; Alternatively, the pixel definition layer includes a T-shaped structure, wherein the sidewalls of the T-shaped structure on a cross section perpendicular to the substrate are vertical straight lines.

5. The display panel according to claim 2, characterized in that, The pattern of the pixel definition layer includes a through-hole opening area formed in the column direction, through which the cathodes of pixels of the same color in the same column are connected; Alternatively, the pattern of the pixel definition layer may include an opening area for the pixel definition layer above the anode, and the cathodes of pixels of the same color in the same column may be connected by lateral slots.

6. A method for preparing a display panel as described in any one of claims 1-5, characterized in that, include: Provide a substrate with driving circuitry; An anode is formed on the substrate by forming an array of pixel units; A patterned undercut or T-shaped pixel definition layer is formed above the anode; The light-emitting layer, cathode, encapsulation layer, and filter layer are formed sequentially. The cathode forms interconnected wiring through the patterned undercut or T-shaped pixel definition layer.

7. A method for manufacturing a display panel according to claim 6, characterized in that, The bottom-cut pixel definition layer is etched into a structure that is wider at the top and narrower at the bottom by first physical etching and then chemical etching.

8. A method for manufacturing a display panel according to claim 6, characterized in that, The sidewall tilt angle of the undercut pixel definition layer is 60° to 85°.

9. A method for manufacturing a display panel according to claim 6, characterized in that, The T-shaped pixel definition layer is etched by first etching the top layer and then etching the bottom layer to create the T-shaped structure.

10. A method for manufacturing a display panel according to claim 6, characterized in that, The undercut or T-shaped pixel definition layer includes a single-layer or multi-layer structure.

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