OLED display panel capable of reducing crosstalk

Abstract

The invention relates to the technical field of semiconductor display, and discloses an OLED display panel capable of reducing crosstalk. The anodes are arranged on the back plate at intervals; the pixel definition layers are arranged between the adjacent anodes; the second light-emitting layer is located on the anode and the pixel definition layer, and the second light-emitting layer comprises a double-color light-emitting material corresponding to a second type of sub-pixels; the charge generation layer is located on the second light-emitting layer and comprises a first region and a second region which are disconnected from each other, the first region is located above the first type of sub-pixels, and the second region is located above the second type of sub-pixels; the first light-emitting layer is located on the charge generation layer, and the first light-emitting layer comprises a monochromatic light-emitting material corresponding to the first type of sub-pixels; and a cathode layer on the first light emitting layer. The crosstalk problem between the sub-pixels is effectively reduced, the process difficulty is reduced, and the yield is improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor display technology, and in particular to an OLED display panel with reduced crosstalk. Background Art

[0002] The pixel density of the micro display is very high, and the spacing between adjacent sub-pixels is about 1um. At this time, the high mobility of conductive layers such as the charge generation layer (CGL), the hole injection layer (HIL), and the hole transport layer (HTL) will cause serious crosstalk between sub-pixels. Usually, only the pixel definition layer (PDL) with an undercut structure can be used to cut off the leakage between sub-pixels, thereby avoiding the crosstalk problem between sub-pixels. However, the undercut structure has the problems of high process difficulty and low yield rate, and the undercut structure occupies a large area, which will lead to a reduction in pixel area and low luminous efficiency. Summary of the invention

[0003] The embodiment of the present application provides an OLED display panel with reduced crosstalk. By combining the cut-off design of the charge generating layer with the double-layer structure of the light-emitting layer, the crosstalk problem between sub-pixels is effectively reduced, the process difficulty is reduced, and the yield rate is improved.

[0004] To achieve the above-mentioned purpose, the technical solution adopted in the present application is: an OLED display panel with reduced crosstalk, comprising:

[0005] Back panel;

[0006] anodes arranged at intervals on the back plate;

[0007] a pixel definition layer disposed between adjacent anodes;

[0008] A second light-emitting layer located on the anode and the pixel definition layer, the second light-emitting layer comprising

[0009] The second type of sub-pixel corresponds to a dual-color luminescent material;

[0010] A charge generation layer located on the second light-emitting layer, the charge generation layer comprising a first region and a second region disconnected from each other, the first region being located above the first type of sub-pixel, and the second region being located above the second type of sub-pixel;

[0011] a first light-emitting layer located on the charge generation layer, the first light-emitting layer comprising a monochromatic light-emitting material corresponding to the first type of sub-pixel; and

[0012] A cathode layer is located on the first light emitting layer.

[0013] Optionally, an edge of the first region contacts an anode corresponding to the first type of sub-pixel.

[0014] Optionally, a first side wall of the pixel definition layer surrounding the first type of sub-pixel has a bottom inscribed structure that destroys the continuity of the second light-emitting layer and the charge generation layer.

[0015] Optionally, the bottom inscribed structure includes an extension portion extending laterally from an upper surface of the pixel definition layer toward a space where the first type of sub-pixel is located, and an area that cannot be covered by evaporation is formed on the first side wall through the extension portion.

[0016] Optionally, the inscribed angle formed by the bottom inscribed structure is smaller than the evaporation angle, so that the second light-emitting layer and the charge generating layer are disconnected at the bottom inscribed structure during evaporation, and the inscribed angle is the angle between the line between the edge of the extension portion and the bottom edge of the first side wall and the upper surface of the anode of the first type of sub-pixel.

[0017] Optionally, the material used for the extension portion is SiO, and the material used for the trapezoidal structure under the pixel definition layer is SiN.

[0018] Optionally, an inclination angle of a second side wall of the pixel definition layer surrounding the second type of sub-pixel is smaller than an evaporation angle.

[0019] Optionally, the first category of sub-pixels are blue pixels, and the second category of sub-pixels include red pixels and green pixels; or the first category of sub-pixels are green pixels, and the second category of sub-pixels include red pixels and blue pixels; or the first category of sub-pixels are red pixels, and the second category of sub-pixels include blue pixels and green pixels.

[0020] Optionally, the sub-pixels are arranged in a stripe pixel arrangement or a delta arrangement.

[0021] Optionally, the display panel further includes a color filter film located on the cathode layer.

[0022] The OLED display panel with reduced crosstalk provided in the embodiment of the present application effectively reduces the crosstalk problem between sub-pixels through the cut-off design of the charge generation layer and the double-layer structure of the light-emitting layer, reduces the process difficulty, and improves the yield rate. The charge generation layer in the first area is set to an edge close to or in contact with the anode at the bottom, causing the second light-emitting layer below the first area to be short-circuited, increasing the voltage applied to the first light-emitting layer, and thus improving the luminous efficiency of the display panel. A PDL with an undercut structure is set only on the first type of sub-pixels, and a PDL structure with a smaller occupied width is selected on other sub-pixels. By reducing the number of PDLs with undercut structures, the impact of the undercut structure on the pixel area is minimized, effectively improving the aperture ratio of the pixel and the luminous efficiency of the display panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings introduced below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 A schematic diagram of the structure of an OLED display panel for reducing crosstalk provided by an embodiment of the present application;

[0025] Figure 2 A schematic diagram of a bottom inscribed structure used in a pixel definition layer provided in an embodiment of the present application;

[0026] Figure 3 A schematic diagram of a strip pixel arrangement provided by an embodiment of the present application;

[0027] Figure 4 A schematic diagram of a delta arrangement provided in one embodiment of the present application;

[0028] Figure 5 A schematic structural diagram of an OLED structure provided in one embodiment of the present application;

[0029] The marks in the accompanying drawings are: 1-backplane, 2-anode, 3-pixel definition layer, 4-second light-emitting layer, 5-charge generation layer, 6-first light-emitting layer, 7-cathode layer, 21, 22, 23-sub-pixels, 51-first area, 52-second area, 511-edge, 31-upper surface, 32-first side wall, 33-extension part, 34-second side wall, 35-trapezoidal structure, 301-connecting line, 30-area that cannot be covered by evaporation, 41-first part, 42-second part. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0031] In the description of the present application, it should be noted that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.

[0032] refer to Figure 1 An embodiment of the present application provides an OLED display panel with reduced crosstalk, including: a backplane 1, anodes 2 arranged at intervals on the backplane 1, a pixel definition layer 3 arranged between adjacent anodes 2, a second light-emitting layer 4 located on the anode 2 and the pixel definition layer 3, a charge generation layer 5 located on the second light-emitting layer 4, a first light-emitting layer 6 located on the charge generation layer 5, and a cathode layer 7 located on the first light-emitting layer 6.

[0033] The backplane 1 can be made of glass, plastic, polymer, silicon or any other desired material. A plurality of mutually spaced anodes 2 are arranged on the backplane 1, and adjacent anodes 2 can be isolated from each other by grooves to form a corresponding sub-pixel array, each anode corresponding to a sub-pixel, and each anode can be independently controlled so that its corresponding sub-pixel generates an independently controlled amount of light. A pixel definition layer 3 can be formed on the backplane 1 between adjacent anodes 2, and each sub-pixel can be separated by the pixel definition layer 3 so that they do not interfere with each other.

[0034] The first light-emitting layer 6 includes a monochromatic light-emitting material corresponding to the first type of sub-pixel, and the second light-emitting layer 4 includes a dual-color light-emitting material corresponding to the second type of sub-pixel. The first type of sub-pixel includes sub-pixels of one color, and the second type of sub-pixel includes sub-pixels of two colors. In specific implementation, the color of the light emitted by the first light-emitting layer 6 and the second light-emitting layer 4 is set according to the requirements, and the present application is not limited thereto, and the color corresponding to the first type of sub-pixel is the same as the color of the light emitted by the first light-emitting layer 6, and the color corresponding to the second type of sub-pixel is the same as the color of the light emitted by the second light-emitting layer 4. For example, the first light-emitting layer is made of a blue light-emitting material, and the second light-emitting layer is a mixture of a red light-emitting material and a green light-emitting material. In this case, the first type of sub-pixel is a blue pixel, and the second type of sub-pixel is a red pixel and a green pixel; the first light-emitting layer is made of a red light-emitting material, and the second light-emitting layer is a mixture of a blue light-emitting material and a green light-emitting material. In this case, the first type of sub-pixel is a red pixel, and the second type of sub-pixel is a blue pixel and a green pixel; the first light-emitting layer is made of a green light-emitting material, and the second light-emitting layer is a mixture of a red light-emitting material and a blue light-emitting material. In this case, the first type of sub-pixel is a green pixel, and the second type of sub-pixel is a red pixel and a green pixel.

[0035] The first light-emitting layer 6 and the second light-emitting layer 4 are organic layers, and the conductivity of organic matter is very low. The thickness of the first light-emitting layer 6 and the second light-emitting layer 4 is much smaller than the lateral length. Therefore, the longitudinal conductivity of the first light-emitting layer 6 and the second light-emitting layer 4 is relatively strong (i.e., the direction from the anode to the cathode), while the lateral conductivity is extremely poor. Therefore, although the second light-emitting layer 4 penetrates the sub-pixel 22 and the sub-pixel 23, there is only a very small crosstalk leakage between the sub-pixel 22 and the sub-pixel 23, which can be ignored.

[0036] The charge generation layer 5 includes a first region 51 and a second region 52 which are disconnected from each other. The first region 51 is located above the first type of sub-pixels (including the sub-pixel 21 ), and the second region is located above the second type of sub-pixels (including the sub-pixels 22 and 23 ).

[0037] When a sub-pixel needs to be lit, a voltage is applied to the anode 2 corresponding to the sub-pixel, and a path is formed among the anode 2, the second light-emitting layer 4 in the area above the anode 2, the charge generating layer 5, the first light-emitting layer 6 and the cathode layer 7, thereby forming a voltage difference between the first light-emitting layer 6 and the second light-emitting layer 4, causing the first light-emitting layer 6 and the second light-emitting layer 4 to emit light of corresponding colors.

[0038] The high-conductivity charge generation layer 5 is a factor that causes leakage crosstalk between sub-pixels. In the embodiment of the present application, the originally connected charge generation layer 5 is divided into a first area 51 covering the first type of sub-pixels and a second area 52 covering the second type of sub-pixels, which effectively cuts off the leakage between the first type of sub-pixels and the second type of sub-pixels, and reduces the crosstalk between the first type of sub-pixels and the second type of sub-pixels. For the two types of sub-pixels in the second type of sub-pixels, their corresponding luminescent materials are all in the second luminescent layer and are not affected by the charge generation layer. There is only very little crosstalk between the two types of sub-pixels. Therefore, the charge generation layer above the second type of sub-pixels is no longer segmented, which can reduce the process difficulty and improve the yield rate.

[0039] by Figure 1 Taking the structure shown as an example, assuming Figure 1 The sub-pixel 21 is a blue pixel, the sub-pixel 22 is a red pixel, the sub-pixel 23 is a green pixel, the first light-emitting layer 6 is a light-emitting layer made of a blue light-emitting material, and the second light-emitting layer 4 is a light-emitting layer made of a mixture of a red light-emitting material and a green light-emitting material. The first region 51 of the charge generation layer in the blue pixel region and the second region 52 of the charge generation layer in the red and green pixel regions are disconnected from each other, thereby cutting off the leakage channel between the blue pixel and the red pixel, and between the blue pixel and the green pixel, thereby reducing the crosstalk between the blue pixel and the red pixel, and between the blue pixel and the green pixel. The red and green pixels are located in the same light-emitting layer and are not affected by the charge generation layer. Therefore, there is only very small crosstalk between the red and green pixels.

[0040] Therefore, the OLED display panel with reduced crosstalk provided in the embodiment of the present application effectively reduces the crosstalk problem between sub-pixels through the cut-off design of the charge generating layer and the double-layer structure of the light-emitting layer, reduces the process difficulty, and improves the yield rate.

[0041] In one possible implementation, reference Figure 1 , an edge 511 of the first region 51 bends downward and contacts the anode 2 corresponding to the first type of sub-pixel, while the second region 52 maintains a certain distance from the anode 2 .

[0042] Since the charge generation layer 5 is usually a metal-doped layer, its conductivity is significantly higher than that of an organic layer such as the second light-emitting layer 4. Therefore, the edge 511 of the first region 51 contacts the anode 2 at the bottom, which causes the second light-emitting layer 4 below the first region 51 to be short-circuited. Therefore, the voltage originally applied to the first light-emitting layer 6 and the second light-emitting layer 4 will be fully applied to the first light-emitting layer 6, thereby increasing the light-emitting brightness of the first light-emitting layer 6.

[0043] Assumptions Figure 1The sub-pixel 21 in the image is a blue pixel, and the corresponding first light-emitting layer 6 is made of a blue light-emitting material. Since the second light-emitting layer 4 below the first region 51 is short-circuited, it does not emit red or green light or only emits a small amount of red or green light, thereby reducing the red and green light in the blue pixel. In addition, compared with the case where it is not short-circuited, the driving voltage applied to the first light-emitting layer 6 becomes larger, thereby increasing the luminous brightness of the blue light.

[0044] Therefore, under the condition of achieving the same luminous brightness, the OLED display panel with reduced crosstalk in the embodiment of the present application requires a lower driving voltage, thereby improving the luminous efficiency of the display panel.

[0045] In a possible implementation, the first side wall of the pixel definition layer around the first type of sub-pixel has a bottom inscribed structure that destroys the continuity of the second light-emitting layer and the charge generation layer. An area that cannot be covered by evaporation is formed at the bottom inscribed structure, resulting in the second light-emitting layer and the charge generation layer forming a depression in the area that cannot be covered by evaporation, so that the second light-emitting layer and the charge generation layer are disconnected at the first side wall.

[0046] refer to Figure 2 , which is a bottom inscribed structure provided in one embodiment of the present application, includes an extension portion 33 extending laterally from the upper surface 31 of the pixel definition layer 3 to the space where the first type of sub-pixel 21 is located, and an area 30 that cannot be covered by evaporation is formed on the first side wall 32 of the pixel definition layer 3 through the extension portion 33. Figure 2 α in the figure represents the evaporation angle. The line between the extended end of the extension portion 33 and the bottom edge of the first side wall 32 is 301, and the angle β formed by the line 301 and the upper surface of the anode 2 of the first type of sub-pixel 21 is used as the inscribed angle of the bottom inscribed structure. The length of the extension portion 33 can be determined according to factors such as the height of the pixel definition layer 3 and the required inscribed angle, and is not limited here.

[0047] exist Figure 2 The bottom inscribed structure shown in FIG. 1 is subjected to evaporation treatment to obtain a structure as shown in FIG. Figure 1 When the second light-emitting layer 4 is evaporated, an area 30 that cannot be covered by the evaporation is formed at the bottom inscribed structure, so that the second light-emitting layer 4 is recessed at the area 30 that cannot be covered by the evaporation, so that the second light-emitting layer 4 is disconnected at the area 30 to form a first part 41 and a second part 42, the first part 41 is attached to the anode of the sub-pixel 21, and the second part 42 is attached to the pixel definition layer 3 and the anode of the sub-pixel 22. Figure 2 Due to the limitation of the evaporation angle and the bottom inscribed structure, the closer to the inscribed angle β, the smaller the thickness of the formed second light-emitting layer 4 is. Therefore, the cross section of the first part 41 of the second light-emitting layer 4 is obtained as follows: Figure 1Similarly, when the charge generation layer 5 is evaporated, a depression is formed in the area 30 that cannot be covered by the evaporation, so that the charge generation layer 5 is disconnected at the area 30 to form a first area 51 and a second area 52, and the charge generation layer is attached to the surface of the first portion 41 to form a Figure 1 The shape of the first region 51 is such that an edge 511 of the first region 51 is close to or in contact with the anode 2 at the bottom.

[0048] In order to ensure that the second light-emitting layer 4 and the charge generation layer 5 can be completely disconnected at the bottom inscribed structure during evaporation, and to ensure that the edge 511 of the charge generation layer in the first region 51 is close to or in contact with the bottom anode 2, the inscribed angle formed by the bottom inscribed structure needs to be smaller than the evaporation angle. The evaporation angle is determined by the evaporation equipment and evaporation process used, and is generally not less than 70°. At this time, the inscribed angle formed by the bottom inscribed structure can be set to a value less than 70°. The size of the inscribed angle formed by the bottom inscribed structure should also take into account issues such as process difficulty and pixel aperture ratio.

[0049] The thickness of the second light-emitting layer 4 and the charge generation layer 5, the height of the pixel definition layer 3, the shape and size of the inscribed angle of the bottom inscribed structure, the length of the extension portion at the top of the pixel definition layer 3 and other parameters and dimensions will affect the final evaporation effect of each layer. In order to achieve a better evaporation effect, the above parameters need to be determined in combination with the demand indicators in actual applications, and are not limited in the embodiments of this application.

[0050] The pixel definition layer 3 may be formed of a single material. Of course, in order to form the desired bottom inscribed structure on the sidewall of the pixel definition layer, the pixel definition layer 3 may be formed of multiple layers of material. For example, Figure 2 The material used for the extension portion 33 of the upper layer of the pixel definition layer 3 shown in the figure may be SiO, and the material used for the trapezoidal structure 35 of the lower layer of the pixel definition layer 3 may be SiN.

[0051] A non-undercut pixel definition layer 3 is used around the second type of sub-pixels to reduce the width occupied by the pixel definition layer 3. Figure 2 The inclination angle γ of the second side wall 34 of the pixel definition layer 3 around the second type of sub-pixels (including sub-pixels 22 and sub-pixels 23) is smaller than the evaporation angle α to ensure that no depressions are generated on the pixel definition layer 3 around the second type of sub-pixels during evaporation, thereby ensuring the continuity of the second light-emitting layer 4 and the charge generation layer 5 in the space corresponding to the second type of sub-pixels.

[0052] Compared with ordinary PDL, the PDL with an undercut structure occupies a larger width. Therefore, the more PDLs with an undercut structure there are, the smaller the effective pixel area of ​​the display panel. The OLED display panel with reduced crosstalk in the embodiment of the present application only sets a PDL with an undercut structure on the first type of sub-pixels, and selects a PDL structure with a smaller occupied width on other sub-pixels. By reducing the number of PDLs with an undercut structure, the impact of the undercut structure on the pixel area is reduced as much as possible, effectively improving the pixel aperture ratio and the luminous efficiency of the display panel. Based on the experimental data in Table 1, it can be seen that compared with the display panel using a full undercut PDL structure, the luminous efficiency of the display panel in the embodiment of the present application can be improved by about 20%, and the pixel aperture ratio can be improved by about 20%.

[0053] In specific implementation, the OLED display panel with reduced crosstalk also includes a color filter (CF) located on the cathode layer, and the arrangement of the color filter matches the arrangement of the sub-pixels in the display panel. The principle of the color filter is to coat BM, R / G / B, and O / C on the glass substrate through pigment dispersion and other processes, so that the white light passing through is filtered into three basic pigment dot matrices of red, blue, and green to achieve color display.

[0054] In a possible implementation manner, the OLED display panel with reduced crosstalk in the embodiment of the present application may also adopt Figure 5 The OLED structure shown includes an anode, a second light-emitting layer, a charge generation layer (CGL), a first light-emitting layer and a cathode, wherein the first light-emitting layer may be composed of a hole injection layer (HIL), a blue light-emitting layer (B-EML) and a hole transport layer (HTL), and the second light-emitting layer is composed of a hole injection layer (HIL), a red and green light-emitting layer (RG-EML) and a hole transport layer (HTL). It should be noted that similar to the principle of the charge generation layer, the PDL of the undercut structure also leads to Figure 5 The hole injection layer and the hole transport layer in the undercut structure are disconnected, thereby reducing crosstalk between sub-pixels.

[0055] The sub-pixel arrangement method that can be adopted by the OLED display panel with reduced crosstalk in the embodiment of the present application includes but is not limited to strip pixel arrangement, delta arrangement, etc. Figure 3 It is a schematic diagram of the structure of strip pixel arrangement. Figure 4 This is a schematic diagram of the delta arrangement structure. Figure 3 and Figure 4 In the embodiment, a pixel definition layer having a bottom inscribed structure is arranged around the B pixel (blue pixel), and a common pixel definition layer is arranged around the R pixel (red pixel) and the G pixel (green pixel), thereby forming a pixel having a bottom inscribed structure. Figure 1A display panel with the structure shown.

[0056] Several display panels with different structures are tested below, and the test results are shown in Table 1. All display panels in Table 1 use OLED structures (for details, refer to Figure 5 ) are the same, and the difference between the display panels lies in the different structures of the pixel definition layers. The pixel definition layer of display panel No. 1 does not use the undercut structure, the pixel definition layer of all sub-pixels in display panel No. 2 uses the undercut structure, and the pixel definition layer of display panel No. 3 uses the undercut structure. Figure 3 The pixel arrangement shown in the figure uses an undercut structure only on blue pixels. The No. 4 display panel adopts Figure 4 The pixel arrangement shown in the figure uses an undercut structure only on blue pixels. The parameters of some layers in display panels 3 and 4 can be referred to Table 2. NTSC coverage is used to characterize the crosstalk between RGB pixels. The higher the NTSC coverage, the smaller the crosstalk between sub-pixels.

[0057] Based on the data in Table 1, it can be found that although the display panel No. 1 that does not use the undercut structure can obtain a higher white light efficiency, the crosstalk between sub-pixels is extremely serious. Display panel No. 2 uses an undercut structure on R, G, and B pixels, so the charge generation layer on the R pixel and the G pixel will drop, resulting in a short circuit between the red and green light-emitting layers, causing the brightness of the red and green light to decrease, and the PDL occupies a larger width than the ordinary PDL, resulting in a reduction in pixel area, further reducing the luminous efficiency. It can also be found from the experimental data in Table 1 that the luminous efficiency of display panel No. 2 is the lowest. Display panels No. 3 and No. 4 both use the display panel structure provided in the embodiments of the present application, which reduces the crosstalk between sub-pixels while ensuring that the display panel has a higher luminous efficiency.

[0058] Table 1

[0059]

[0060] Table 2

[0061] Film Material thickness Red and Green OLED / 100nm CGL ET doped lithium 20nm Blue OLED / 110nm PDL Upper S N 65nm PDL Lower Layer SiO 20nm

[0062] The above embodiments are only used to introduce the technical solutions of the present application in detail, but the description of the above embodiments is only used to help understand the methods of the embodiments of the present application and should not be understood as limiting the embodiments of the present application. Any changes or substitutions that can be easily thought of by technicians in this technical field should be included in the protection scope of the embodiments of the present application.

Claims

1. An OLED display panel with reduced crosstalk, characterized in that: include: Back panel (1); Anodes (2) are arranged at intervals on the back plate; A pixel definition layer (3) disposed between adjacent anodes; a second light-emitting layer (4) located on the anode and the pixel definition layer, the second light-emitting layer comprising a two-color light-emitting material corresponding to a second type of sub-pixel (22, 23); a charge generation layer (5) located on the second light-emitting layer, the charge generation layer comprising a first region (51) and a second region (52) disconnected from each other, the first region being located above a first type of sub-pixel (21), and the second region being located above a second type of sub-pixel (22, 23); a first light-emitting layer (6) located on the charge generation layer, the first light-emitting layer comprising a monochromatic light-emitting material corresponding to the first type of sub-pixel; and A cathode layer (7) is located on the first light-emitting layer.

2. The display panel according to claim 1, characterized in that: The edge of the first region (51) contacts the anode corresponding to the first type of sub-pixel (21).

3. The display panel according to claim 1 or 2, characterized in that: The first side wall (32) of the pixel definition layer surrounding the first type of sub-pixel has a bottom inscribed structure that destroys the continuity of the second light-emitting layer and the charge generation layer.

4. The display panel according to claim 3, characterized in that: The bottom inscribed structure comprises an extension portion (33) extending laterally from the upper surface of the pixel definition layer to the space where the first type of sub-pixel is located, and an area that cannot be covered by evaporation is formed on the first side wall through the extension portion.

5. The display panel according to claim 4, characterized in that: The inscribed angle formed by the bottom inscribed structure is smaller than the evaporation angle, so that the second light-emitting layer and the charge generating layer are disconnected at the bottom inscribed structure during evaporation. The inscribed angle is the angle between the line between the edge of the extension portion and the bottom edge of the first side wall and the upper surface of the anode of the first type of sub-pixel.

6. The display panel according to claim 4, characterized in that: The material used for the extension part is SiO, and the material used for the trapezoidal structure (35) under the pixel definition layer is SiN.

7. The display panel according to claim 1, characterized in that: The inclination angle of the second side wall of the pixel definition layer surrounding the second type of sub-pixels is smaller than the evaporation angle.

8. The display panel according to claim 1, characterized in that: The first type of sub-pixels are blue pixels, and the second type of sub-pixels include red pixels and green pixels; or The first type of sub-pixels are green pixels, and the second type of sub-pixels include red pixels and blue pixels; or The first type of sub-pixels are red pixels, and the second type of sub-pixels include blue pixels and green pixels.

9. The display panel according to claim 1, characterized in that: The sub-pixels are arranged in a stripe pixel arrangement or a delta arrangement.

10. The display panel according to claim 1, characterized in that: Also included is a color filter film located on the cathode layer.

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