Display substrate and display device

Abstract

The invention provides a display substrate and a display device. The display substrate comprises a substrate; the plurality of pixel units are arranged in an array, each pixel unit comprises a plurality of sub-pixels, and each sub-pixel comprises a first electrode, a light-emitting functional layer and a second electrode which are stacked on the substrate; the light extraction layer is arranged on the side, away from the substrate, of the second electrode, and the light extraction layer is provided with an opening area exposing the second electrode; the auxiliary electrode layer is arranged on the side, away from the second electrode, of the light extraction layer, the orthographic projection of the auxiliary electrode layer and the orthographic projection of the second electrode on the substrate body are at least partially overlapped, and the auxiliary electrode layer is electrically connected with the second electrode through the opening area. Wherein at least one part of light emitted by the sub-pixels enters the auxiliary electrode layer through the light extraction layer and then is transmitted from the auxiliary electrode layer.

Description

Technical Field

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

[0002] At present, electroluminescent devices are becoming more and more important in the display industry. For example, organic light emitting diodes (OLED) have been widely promoted and applied in recent years due to their advantages such as high color gamut, bendability, and fast response time. In addition, quantum dot light emitting diodes (QLED) have also received more and more attention in recent years due to their low manufacturing cost and high color gamut. Summary of the invention

[0003] In a first aspect of the present disclosure, a display substrate is provided, comprising: a base substrate; a plurality of pixel units arranged in an array, each pixel unit comprising a plurality of sub-pixels, each sub-pixel comprising: a first electrode, a light-emitting functional layer and a second electrode stacked on the base substrate; a light extraction layer, arranged on a side of the second electrode away from the base substrate, the light extraction layer having an opening area exposing the second electrode; an auxiliary electrode layer, arranged on a side of the light extraction layer away from the second electrode, the auxiliary electrode layer at least partially overlapping with the orthographic projection of the second electrode on the base substrate, the auxiliary electrode layer being electrically connected to the second electrode through the opening area; wherein at least a portion of the light emitted by the sub-pixels is incident on the auxiliary electrode layer through the light extraction layer, and then transmitted from the auxiliary electrode layer.

[0004] In some optional embodiments, the plurality of sub-pixels include a first sub-pixel, a second sub-pixel, and a third sub-pixel, and the light emission wavelength of the first sub-pixel is greater than the light emission wavelengths of the second sub-pixel and the third sub-pixel. The orthographic projection of the light extraction layer on the base substrate at least partially overlaps with the orthographic projection of the second sub-pixel on the base substrate; and / or the orthographic projection of the light extraction layer on the base substrate at least partially overlaps with the orthographic projection of the third sub-pixel on the base substrate.

[0005] In some optional embodiments, the orthographic projections of the second sub-pixel and the third sub-pixel on the base substrate are located within the orthographic projection range of the light extraction layer on the base substrate.

[0006] In some optional embodiments, the orthographic projection of the opening area on the base substrate at least partially overlaps with the orthographic projection of the first sub-pixel on the base substrate, and the auxiliary electrode layer covers the opening area and contacts the second electrode exposed in the opening area.

[0007] In some optional implementations, the orthographic projection of the first sub-pixel on the base substrate is located within the orthographic projection range of the opening area on the base substrate.

[0008] In some optional embodiments, the first sub-pixel is a red sub-pixel, the second sub-pixel is a green sub-pixel, and the third sub-pixel is a blue sub-pixel.

[0009] In some optional embodiments, the thickness of the light extraction layer corresponding to the sub-pixels of different colors is the same, or the thickness of the light extraction layer corresponding to the sub-pixels of different colors is different.

[0010] In some optional embodiments, the light extraction layer includes: a first sub-light extraction layer and a second sub-light extraction layer that are stacked, the first sub-light extraction layer is closer to the second electrode than the second sub-light extraction layer, and the refractive index of the first sub-light extraction layer is greater than the refractive index of the second sub-light extraction layer.

[0011] In some optional embodiments, the thickness of the first sub-light extraction layer is 50 to 100 nanometers, the thickness of the second sub-light extraction layer is 50 to 150 nanometers, and the thickness of the auxiliary electrode layer is 100 to 1000 nanometers.

[0012] In some optional embodiments, the first sub-pixel is a red sub-pixel, the second sub-pixel is a green sub-pixel, and the third sub-pixel is a blue sub-pixel. The auxiliary electrode layer includes: a first region corresponding to the first sub-pixel, a second region corresponding to the second sub-pixel, and a third region corresponding to the third sub-pixel. In a direction perpendicular to the substrate, the thickness of the third region is less than the thickness of the second region, and the thickness of the first region is less than or equal to the thickness of the second region.

[0013] In some optional embodiments, along a direction perpendicular to the substrate, the thickness of the first region is 100 to 150 nanometers, the thickness of the second region is 250 to 350 nanometers, and the thickness of the third region is 100 to 150 nanometers.

[0014] In some optional embodiments, the light extraction layer includes: a plurality of light extraction units, the opening area is provided between adjacent light extraction units, and each of the light extraction units covers one sub-pixel or a plurality of sub-pixels.

[0015] In some optional implementations, each of the light extraction units covers one of the pixel units.

[0016] In some optional embodiments, the pixel unit includes: a first sub-pixel, a second sub-pixel and a third sub-pixel, the first sub-pixel, the second sub-pixel and the third sub-pixel include a first edge and a second edge arranged opposite to the first edge, the first edge is a straight line, and the second edge is a curve. A line connecting the center points of the first sub-pixel, the second sub-pixel and the third sub-pixel forms a triangle, the second edge of the first sub-pixel is arranged opposite to the second edge of the second sub-pixel, and the second edge of the third sub-pixel is arranged toward the first sub-pixel and the second sub-pixel.

[0017] In some optional embodiments, the planar shapes of the first sub-pixel, the second sub-pixel and the third sub-pixel are circular, semi-circular or semi-elliptical.

[0018] In some optional embodiments, the planar shape of the light extraction unit is a hexagon, and the hexagon includes: a first side, a second side, a third side, a fourth side, a fifth side and a sixth side connected in sequence, the first side is arranged opposite to the fourth side, the second side is arranged opposite to the sixth side, and the third side is arranged opposite to the fifth side. The length of the first side is less than the length of the fourth side, and the extension direction of the fourth side is parallel to the arrangement direction of the first sub-pixel and the second sub-pixel. The first edge of the first sub-pixel and the first edge of the second sub-pixel are arranged opposite to the third side and the fifth side respectively, and the first edge of the third sub-pixel is arranged opposite to the first side.

[0019] In some optional embodiments, the pixel unit includes: a first sub-pixel, two second sub-pixels and a third sub-pixel, the area of ​​the second sub-pixel is smaller than the area of ​​the first sub-pixel and the area of ​​the third sub-pixel, and the center point connection line of the first sub-pixel, the two second sub-pixels and the third sub-pixel is a rhombus. The spacing between adjacent first sub-pixels and the third sub-pixel is a first distance, the spacing between adjacent second sub-pixels is a second distance, the spacing between adjacent first sub-pixels and the second sub-pixel is a third distance, and the spacing between adjacent second sub-pixels and the third sub-pixel is a fourth distance, and the first distance and the second distance are greater than the third distance and the fourth distance. The light extraction unit is a bent strip structure, and among the plurality of light extraction units, at least a portion of the light extraction units covers one first sub-pixel, one second sub-pixel and one third sub-pixel, and at least a portion of the light extraction units covers one first sub-pixel, two second sub-pixels and one third sub-pixel.

[0020] In some optional embodiments, the display substrate includes a plurality of the light extraction layers and a plurality of the auxiliary electrode layers, and the plurality of the light extraction layers and the plurality of the auxiliary electrode layers are alternately stacked on a side of the second electrode away from the base substrate.

[0021] In some optional embodiments, the first electrode is a reflective electrode, the second electrode is configured to partially transmit and partially reflect the light emitted by the light-emitting functional layer, and the second electrodes of adjacent sub-pixels are connected to each other.

[0022] In some optional embodiments, the second electrode includes a metal material, and the auxiliary electrode layer includes: a transparent conductive material.

[0023] In a second aspect of the present disclosure, a display substrate is provided, comprising: a base substrate; a plurality of pixel units arranged in an array, each pixel unit comprising a first sub-pixel, a second sub-pixel and a third sub-pixel, the first sub-pixel being a red sub-pixel, and each sub-pixel comprising: a first electrode, a light-emitting functional layer and a second electrode stacked on the base substrate; a light extraction layer, arranged on a side of the second electrode away from the base substrate, the light extraction layer covering the second sub-pixel and the third sub-pixel, and having an opening area exposing the second electrode of the first sub-pixel; an auxiliary electrode layer, arranged on a side of the light extraction layer away from the second electrode, the auxiliary electrode layer covering the light extraction layer and the opening area, and being electrically connected to the exposed second electrode at the bottom of the opening area; light emitted by the first sub-pixel is emitted through the auxiliary electrode layer, and light emitted by the second sub-pixel and the third sub-pixel is emitted through the light extraction layer and the auxiliary electrode layer.

[0024] In a third aspect of the present disclosure, a display device is provided, comprising: the display substrate provided by the first aspect or the second aspect.

[0025] In the display substrate and display device provided by some embodiments of the present disclosure, by adding an auxiliary electrode layer connected in parallel with the second electrode on the side of the second electrode away from the base substrate, the resistance of the second electrode can be effectively reduced. In addition, by adding a light extraction layer between the auxiliary electrode layer and the second electrode, at least a portion of the light emitted by the sub-pixel is incident on the auxiliary electrode layer through the light extraction layer, and then transmitted from the auxiliary electrode layer. On the one hand, the second electrode can be protected by the light extraction layer to reduce the damage to the second electrode caused by the preparation of the auxiliary electrode layer. On the other hand, the loss of luminous efficiency caused by the auxiliary electrode layer can be compensated, which is conducive to reducing the resistance of the second electrode to improve the brightness uniformity while ensuring the luminous efficiency of the display substrate.

[0026] The above description is only an overview of the technical solutions provided by some embodiments of the present disclosure. In order to more clearly understand the technical means of the embodiments of the present disclosure, they can be implemented in accordance with the contents of the specification. In order to make the embodiments of the present disclosure more obvious and easy to understand, the specific implementation methods of the embodiments of the present disclosure are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present disclosure, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A schematic plan view of a display substrate according to some embodiments of the present disclosure is shown;

[0029] Figure 2 A schematic diagram showing a stacked structure of a display substrate according to some embodiments of the present disclosure is shown;

[0030] Figure 3 A schematic diagram showing the layout of the light extraction unit of some embodiments of the present disclosure is shown;

[0031] Figure 4 Schematic diagrams showing the layout of light extraction units in other embodiments of the present disclosure;

[0032] Figure 5 A schematic diagram of an exemplary pixel arrangement is shown;

[0033] Figure 6 A schematic plan view showing a pixel structure and a light extraction layer in some embodiments of the present disclosure;

[0034] Figure 7 Another exemplary pixel arrangement schematic diagram is shown;

[0035] Figure 8 A schematic plan view showing a pixel structure and a light extraction layer in some embodiments of the present disclosure;

[0036] Fig. 9 A schematic diagram showing a stacked structure of a display substrate according to some embodiments of the present disclosure is shown;

[0037] Fig.10 Shows Fig. 9 A plan view of a display substrate;

[0038] Fig.11 A schematic diagram showing a stacked structure of a display substrate according to some embodiments of the present disclosure is shown;

[0039] Fig.12The test result diagram of the first set of comparative tests is shown;

[0040] Fig.13 Graphs showing test results of the second set of comparative tests;

[0041] Fig.14 The test result diagram of the third group of comparative tests is shown;

[0042] Fig.15 A schematic diagram showing a stacked structure of a display substrate according to some embodiments of the present disclosure is shown;

[0043] Fig.16 Graphs showing test results of the fourth set of comparative tests;

[0044] Fig.17 A schematic diagram showing a stacked structure of a display substrate according to some embodiments of the present disclosure is shown;

[0045] Fig.18 A schematic structural diagram of a display device according to some embodiments of the present disclosure is shown. DETAILED DESCRIPTION

[0046] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0047] It should be noted that the term "and / or" used herein is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent three situations: A exists alone, A and B exist at the same time, and B exists alone. "Multiple" includes two or more than two situations. "Include" or "comprises" and other similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Up", "down", "left", "right", etc. are only used to indicate relative position relationships. When the absolute position of the described object changes, the relative position relationship may also change accordingly.

[0048] The terms "parallel", "perpendicular", and "equal" appearing in this document include the situations described and situations similar to the situations described, and the range of the similar situations is within an acceptable deviation range, wherein the acceptable deviation range is determined by a person of ordinary skill in the art taking into account the measurement being discussed and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range of approximate parallelism can be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity can also be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality can be, for example, the difference between the two equalities is less than or equal to 5% of either one.

[0049] It should be understood that in the exemplary embodiments of the present disclosure, when a layer or an element is referred to as being on another layer or substrate, it may be that the layer or element is directly on the other layer or substrate, or there may be an intermediate layer between the layer or element and the other layer or substrate. "Thickness" refers to the thickness in a direction perpendicular to the substrate. "A and B are arranged in the same layer" refers to a layer structure formed by a single patterning process using the same mask after A and B adopt the same film forming process to form a film layer for forming a specific pattern. "The orthographic projection of B is within the range of the orthographic projection of A" means that the boundary of the orthographic projection of B falls within the boundary of the orthographic projection of A, or the boundary of the orthographic projection of A overlaps with the boundary of the orthographic projection of B.

[0050] In order to reduce the cathode resistance in relevant display substrates, the following technical solutions are generally adopted: 1) Select a metal with higher conductivity as the cathode, but since the selection of the cathode metal also needs to consider the energy level matching of the electron transport layer adjacent to the cathode, the actual optimization space is small. 2) Reduce the cathode resistance by adding metal wiring (auxiliary cathode) in the non-display area. 3) Prepare a transparent auxiliary electrode on the cathode to form a parallel resistance with the cathode, thereby reducing the cathode resistance.

[0051] In order to reduce the cathode resistance in related display substrates, the following technical solutions are generally adopted: 1) Select a metal with higher conductivity as the cathode, but since the selection of the cathode metal also needs to consider the energy level matching of the electron transport layer adjacent to the cathode, the actual optimization space is small; 2) Reduce the cathode resistance by adding metal wiring (auxiliary cathode) in the non-pixel area. 3) Prepare a transparent auxiliary electrode on the cathode to form a parallel resistance with the original cathode, thereby reducing the cathode resistance.

[0052] However, the inventors have found that if a transparent auxiliary electrode is formed directly on the cathode by a sputtering process, the principle of the sputtering process is to use a high-energy ion beam to bombard the target material, transfer the kinetic energy of the ions to the target atoms, and splash out from the target surface and deposit on the substrate surface. Since the sputtering energy is very high, the cathode and the electroluminescent functional layer will be damaged, resulting in a high leakage current of the electroluminescent device. The high leakage current will cause the brightness of the electroluminescent device to decay faster, affecting the service life of the electroluminescent device. In addition, the transparent auxiliary electrode is directly sputtered onto the metal cathode, which will also cause the luminous efficiency of the electroluminescent device to decrease. For example, when the transparent auxiliary electrode is indium zinc oxide (IZO), the luminous efficiency decreases by more than 10%, thereby increasing the power consumption of the display substrate.

[0053] In view of this, the inventors have conducted further research to achieve the goal of reducing the resistance of the second electrode (such as the cathode) to improve the brightness uniformity while ensuring the luminous efficiency of the display substrate. Below, the display substrate and display device provided by some embodiments of the present disclosure are described in detail with reference to the accompanying drawings.

[0054] Some embodiments of the present disclosure provide a display substrate, which includes: a base substrate and a plurality of pixel units arranged in an array on the base substrate. Each pixel unit includes a plurality of sub-pixels, and each sub-pixel includes: a first electrode, a light-emitting functional layer and a second electrode stacked on the base substrate. In addition, the display substrate also includes: a light extraction layer and an auxiliary electrode layer. The light extraction layer is arranged on the side of the second electrode away from the base substrate, and the light extraction layer has an opening area exposing the second electrode; the auxiliary electrode layer is arranged on the side of the light extraction layer away from the second electrode, and the auxiliary electrode layer and the orthographic projection of the second electrode on the base substrate at least partially overlap, and the auxiliary electrode layer is electrically connected to the second electrode through the above-mentioned opening area to realize the parallel connection of the auxiliary electrode layer and the second electrode. Among them, the light emitted by at least a part of the sub-pixels is incident on the auxiliary electrode layer through the light extraction layer, and then transmitted from the auxiliary electrode layer.

[0055] By adding an auxiliary electrode layer connected in parallel with the second electrode on the side of the second electrode away from the base substrate, the resistance of the second electrode can be effectively reduced. In addition, by adding a light extraction layer between the auxiliary electrode layer and the second electrode, at least a portion of the light emitted by the sub-pixel is incident on the auxiliary electrode layer through the light extraction layer and then transmitted from the auxiliary electrode layer. On the one hand, the second electrode can be protected by the light extraction layer to reduce the damage to the second electrode caused by the preparation of the auxiliary electrode layer. On the other hand, the loss of luminous efficiency caused by the auxiliary electrode layer can be compensated, which is conducive to reducing the resistance of the second electrode to improve the brightness uniformity while ensuring the luminous efficiency of the display substrate.

[0056] Figure 1 FIG. 2 shows a schematic plan view of a display substrate of some embodiments of the present disclosure. Figure 1As shown, the display substrate 10 may include: a display area DR and a non-display area NR. The display area DR is an area on the display substrate 10 for displaying images, and the non-display area NR is an area on the display substrate 10 other than the display area DR. The non-display area NR may be located on at least one side (e.g., one side, or multiple sides) of the display area DR. For example, the non-display area NR may be arranged around the display area DR.

[0057] The display region DR is provided with a plurality of pixel units P arrayed in a first direction and a second direction. For example, the plurality of pixel units P may be arranged in M ​​rows and N columns, where M and N are integers greater than or equal to 2. The first direction is the pixel row direction, and the second direction is the pixel column direction. The first direction and the second direction intersect, such as being perpendicular to each other.

[0058] Each pixel unit P includes a plurality of sub-pixels, each of which can display a single color, such as a red sub-pixel displays red, a green sub-pixel displays green, and a blue sub-pixel displays blue. The brightness (grayscale) of sub-pixels of different colors in each pixel unit P can be adjusted, and multiple colors can be displayed by color combination and superposition, thereby realizing full-color display of the display substrate 10.

[0059] For example, the plurality of sub-pixels may include a first sub-pixel p1, a second sub-pixel p2, and a third sub-pixel p3, and different sub-pixels emit different colors. For example, the first sub-pixel p1 may be a red sub-pixel, one of the second sub-pixel p2 and the third sub-pixel p3 may be a green sub-pixel, and the other may be a blue sub-pixel, such as the second sub-pixel p2 may be a green sub-pixel, and the third sub-pixel p3 may be a blue sub-pixel.

[0060] Each sub-pixel may include an electroluminescent device and a pixel driving circuit for driving the electroluminescent device. For example, the electroluminescent device may be an OLED device or a QLED device, etc. For example, a red sub-pixel may include an electroluminescent device for emitting red light, a green sub-pixel may include an electroluminescent device for emitting green light, and a blue sub-pixel may include an electroluminescent device for emitting blue light.

[0061] For example, Figure 1 As shown, the display substrate 10 further includes a plurality of scan lines GL and a plurality of data lines DL. The plurality of scan lines GL and the plurality of data lines DL intersect each other to define a plurality of pixel areas distributed in an array in the display area DR.

[0062] For example, Figure 1As shown, the display substrate 10 may further include a scan drive circuit SC and a data drive circuit DC located in the non-display area NR. The scan drive circuit SC may be, for example, a gate drive circuit (such as a GOA drive circuit). The scan drive circuit SC is connected to the pixel drive circuit through the scan line GL to provide various scan signals, and the data drive circuit DC is connected to the pixel drive circuit through the data line DL to provide data signals. It should be noted that Figure 1 The positional relationship between the scan driving circuit SC and the data driving circuit DC, the scan lines GL and the data lines DL in the display substrate 10 shown in FIG. 1 is only an example, and the actual arrangement position can be designed as required. Figure 1 As shown, the scan driving circuit SC is disposed in the non-display area on one side of the display substrate 10 , or the scan driving circuit SC may be disposed in the non-display areas on two opposite sides of the display substrate 10 .

[0063] The pixel driving circuit may include multiple electronic components such as transistors and capacitors. For example, the pixel driving circuit may include three transistors and one capacitor, forming a 3T1C (i.e., a driving transistor, two switching transistors and one capacitor). For another example, the pixel driving circuit may also include more than three transistors and at least one capacitor, such as a 4T1C (i.e., a driving transistor, three switching transistors and one capacitor), a 5T1C (i.e., a driving transistor, four switching transistors and one capacitor) or a 7T1C (i.e., a driving transistor, six switching transistors and one capacitor), etc. Among them, the transistor may be a thin film transistor (Thin Film Transistor, referred to as TFT), a field effect transistor (metal oxide semiconductor, referred to as MOS) or other switching devices with the same characteristics.

[0064] It can be understood that the transistor may include a control electrode, a first electrode, and a second electrode. The control electrode is the gate of the transistor, the first electrode is one of the source and drain of the transistor, and the second electrode is the other of the source and drain of the transistor. Since the source and drain of the transistor may be symmetrical in structure, the source and drain may be structurally indistinguishable, so the source of the transistor is called the first electrode, and may also be called the second electrode.

[0065] Figure 2 FIG. 2 shows a schematic diagram of a stacked structure of a display substrate of some embodiments of the present disclosure. Figure 2 As shown, in a direction perpendicular to the surface of the display substrate 10 , the display substrate 10 may include: a base substrate 100 , a driving circuit layer 101 , a pixel defining layer 110 , an electroluminescent device 120 , a light extraction layer 130 and an auxiliary electrode layer 140 .

[0066] For example, the substrate 100 may be a rigid substrate, which may include, for example, a glass substrate, a PMMA (Polymethyl methacrylate) substrate, a silicon substrate, etc. In this case, the display substrate 10 may be a rigid display substrate.

[0067] For another example, the substrate 100 may be a flexible substrate. The flexible substrate may include, for example, a PET (Polyethylene terephthalate) substrate, a PEN (Polyethylenenaphthalate diformic acid glycol ester) substrate, or a PI (Polyimide) substrate. In this case, the display substrate 10 may be a flexible display substrate.

[0068] It should be noted that the base substrate 100 may be a one-layer structure or a multi-layer structure. For example, the base substrate 100 may include at least one flexible substrate and at least one buffer layer, and the flexible substrate and the buffer layer are alternately stacked.

[0069] The pixel defining layer 110 has a plurality of pixel openings, each of which is configured to define a light emitting region of an electroluminescent device 120 .

[0070] In a direction away from the base substrate 100, the electroluminescent device 120 may include a first electrode 121, a light-emitting functional layer 122, and a second electrode 123 which are sequentially stacked. One of the first electrode 121 and the second electrode 123 serves as an anode of the electroluminescent device 120, and the other serves as a cathode. The light-emitting functional layer 122 may at least include: a light-emitting layer (EML), which emits display light under the drive of the first electrode 121 and the second electrode 123. In some exemplary embodiments, the light-emitting functional layer 122 may also include any one or more of the following: a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer (EBL), a hole blocking layer (HBL), an electron transport layer (ETL), and an electron injection layer (EIL), which may be arranged according to actual needs, and the present disclosure does not limit this.

[0071] For example, Figure 2As shown, the light-emitting functional layer 122 can be divided into: a pixelated layer 122a and a common layer 122b. The pixelated layer 122a is arranged corresponding to each sub-pixel, and the pixelated layers 122a of sub-pixels of different colors are isolated from each other. For example, the pixelated layer 122a may include the above-mentioned light-emitting layer (EML). The common layers 122b of each electroluminescent device 120 are interconnected to form an integrated structure. For example, the common layer 122b can be formed by an evaporation process. For example, the common layer 122b may include the above-mentioned electron transport layer (ETL) and the electron injection layer (EIL).

[0072] Taking the first electrode 121 as an anode and the second electrode 123 as a cathode as an example, for example, the structure of the first electrode 121 can be a composite structure composed of a transparent conductive oxide film / metal film / transparent conductive oxide film stacked in sequence. The material of the transparent conductive oxide film is, for example, any one of ITO (Indium tin oxide) and IZO (Indium zinc oxide), and the material of the metal film can be, for example, any one or more of aluminum (Al), silver (Ag), titanium (Ti), molybdenum (Mo), etc. For another example, the structure of the first electrode 121 can also be a single-layer structure, such as the material of the single-layer structure can be any one of aluminum (Al), silver (Ag), titanium (Ti), molybdenum (Mo).

[0073] Each pixel opening exposes at least a portion of the first electrode 121 of the corresponding electroluminescent device 120 , and at least a portion of the light-emitting functional layer 122 is located in the corresponding pixel opening and is electrically connected to the corresponding first electrode 121 .

[0074] For example, the second electrodes 123 of adjacent electroluminescent devices 120 may be connected to each other, such as Figure 2 The entire layer is arranged as shown in , so as to facilitate the access of voltage signals. For example, the second electrode 123 may include a metal material, such as any one of lithium (Li), aluminum (Al), magnesium (Mg), silver (Ag) and other metal materials, or alloys of any of the above materials such as magnesium-silver alloy and aluminum-lithium alloy. For example, the first electrode 121 can be used as a reflective electrode, and the second electrode 123 is configured to partially transmit and partially reflect the light emitted by the light-emitting functional layer 122, so that the electroluminescent device 120 can achieve a strong microcavity effect, thereby achieving a better color gamut and luminous efficiency. For example, the thickness of the second electrode 123 can be 5 to 20 nanometers, such as 5 nanometers, 10 nanometers, 15 nanometers or 20 nanometers, so that the second electrode 123 has a light-transmitting property.

[0075] The driving circuit layer 101 is stacked between the base substrate 100 and the pixel defining layer 110, and is at least configured to form a pixel driving circuit for each of the above-mentioned sub-pixels. Of course, in addition to the pixel driving circuit, the driving circuit layer 101 can also be configured to form other functional circuits according to the needs of the actual application scenario. For example, in the display substrate 10 with a fingerprint recognition function, the driving circuit layer 101 can also be configured to form a photosensitive element, and the present disclosure does not limit this.

[0076] For example, the driving circuit layer 101 may include at least: an active layer, a first conductive pattern layer, a second conductive pattern layer, a third conductive pattern layer, and an insulating layer separating these functional layers, which are stacked in sequence. These layers may form a plurality of pixel driving circuits.

[0077] It should be noted that the "pattern layer" may be a layer structure containing a specific pattern formed by forming at least one film layer using the same film forming process and then performing a composition process on the at least one film layer. Depending on the specific pattern, the composition process may include multiple coating, exposure, development or etching processes, and the specific pattern in the formed layer structure may be continuous or discontinuous, and these specific patterns may also be at different heights (or thicknesses). The "conductive pattern layer" here refers to a pattern layer with conductive properties, which is made of conductive materials.

[0078] For example, the active layer may include active patterns (also referred to as channel regions) of each transistor in the pixel driving circuit. The first conductive pattern layer may also be referred to as the first gate metal layer (Gate1 layer), and may include: the gates of each transistor in the pixel driving circuit. In addition, the first conductive pattern layer may also include: the first capacitor plate of the capacitor in the pixel driving circuit. For example, the gate pattern of the transistor may be used as the first capacitor plate at the same time, or the first capacitor plate may be additionally provided in the first conductive pattern layer. The specific structure is provided according to actual needs, and the present disclosure does not limit this. The second conductive pattern layer may also be referred to as the second gate metal layer (Gate2 layer), and may include: the second capacitor plate of the capacitor in the pixel driving circuit. The first capacitor plate and the second capacitor plate are arranged relative to each other to form a capacitor in the pixel driving circuit. The third conductive pattern layer may also be referred to as the first metal routing layer (SD1 layer), and may include: the first electrode and the second electrode, i.e., the source electrode and the drain electrode, of each transistor in the pixel driving circuit.

[0079] In addition, the first conductive pattern layer, the second conductive pattern layer and the third conductive pattern layer may also include a plurality of signal lines. For example, the first conductive pattern layer may also include: a reset signal line, a scan signal line and an enable signal line; the second conductive pattern layer may also include: an initialization signal line. For details, please refer to the relevant technology and will not be described in detail here.

[0080] It should be noted that, in some exemplary embodiments, the driving circuit layer 101 may further include more conductive pattern layers, such as a fourth conductive pattern layer, which may also be called a first metal routing layer (SD2 layer), or even a fifth conductive pattern layer, which may also be called a first metal routing layer (SD3 layer). It can be set according to actual needs, and the present disclosure does not impose any restrictions on this.

[0081] The light extraction layer 130 (capping layer, referred to as CPL) is arranged on the side of the second electrode 123 of the photoluminescent device away from the base substrate 100. On the one hand, it can protect the second electrode 123, and on the other hand, it can also extract a part of the light that is confined to propagate in the microcavity structure of the display substrate 10, so as to increase the light emitted by the display substrate 10, thereby improving the electro-optical conversion efficiency of the electroluminescent device 120. It can be understood that among the light emitted from the light-emitting side of the electroluminescent device 120, some light with a large incident angle is prone to total reflection and is reflected back into the electroluminescent device 120 and cannot go out. By adding a light extraction layer 130 outside the light-emitting side of the electroluminescent device 120 to change the travel path of the light, the light coupling efficiency of the device can be effectively improved, so that the light originally confined inside the device can be emitted, showing a higher light extraction efficiency.

[0082] In some exemplary embodiments, the thickness of the light extraction layer 130 corresponding to the sub-pixels of different colors may be the same to simplify the process. Alternatively, the thickness of the light extraction layer 130 corresponding to the sub-pixels of different colors may also be different, so as to specifically adjust the microcavity length corresponding to the sub-pixels of different colors by changing the thickness of the light extraction layer 130, thereby further improving the luminous efficiency of the electroluminescent device 120.

[0083] The light extraction layer 130 may be a single-layer structure or a multi-layer structure, and may be arranged according to actual needs. For example, the light extraction layer 130 may include: a first sub-light extraction layer 131 and a second sub-light extraction layer 132 that are stacked, the first sub-light extraction layer 131 being closer to the second electrode 123 than the second sub-light extraction layer 132, and the refractive index of the first sub-light extraction layer 131 being greater than the refractive index of the second sub-light extraction layer 132, so as to further improve the light extraction efficiency of the light extraction layer 130.

[0084] For example, for the visible light band (such as 450-780 nm), the refractive index of the first sub-light extraction layer 131 can be greater than 2.0, and the refractive index of the second sub-light extraction layer 132 can be less than or equal to 1.4, and the absorption coefficients of the first sub-light extraction layer 131 and the second sub-light extraction layer 132 can both be less than or equal to 0.01.

[0085] For example, the first sub-light extraction layer 131 can be made of materials with a higher refractive index such as N,N′-di(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4-4′-diamine (NPB), triphenyldiamine derivative (TPD), N,N'-diphenyl-N,N'-di(4'-(N,N-di(1-naphthyl)-amino)-4-biphenyl)-benzidine (TPTE), 1,3,5-tri(N-3-methylphenyl-N-phenylamino)benzene (TDAB), copper phthalocyanine (CuPc), etc. The second sub-light extraction layer 132 can be made of LiF, N,N′-diphenyl-N,N′-di(9-phenyl-9H-carbazole-3-yl)biphenyl-4,4′-diamine, N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazole-3-yl)phenyl)-9H-fluorene-2-amine, 4,4′,4″-tri(3-methylphenylphenylamino)triphenylamine, N,N′-di(1-naphthyl)-N,N′-diamine. Materials having a relatively low refractive index include phenyl[1,1'-biphenyl]-4,4'-diamine or 4,4'-bis[N-(3-methylphenyl)-N-phenylamino]biphenyl, N4,N4'-diphenyl-N4,N4'-bis(9-phenyl-9H-carbazole-3-yl)diphenyl-4,4'-diamine, N(diphenyl-4-yl)9,9-dimethyl-N-(4(9-phenyl-9H-carbazole-3-yl)phenyl)-9H-fluorene-2-amine, and the like.

[0086] The thickness of the first sub-light extraction layer 131 and the second sub-light extraction layer 132 can be set according to actual needs. For example, the thickness of the first sub-light extraction layer 131 can be 50 to 100 nanometers, such as 50 nanometers, 60 nanometers, 80 nanometers or 100 nanometers, etc.; the thickness of the second sub-light extraction layer 132 can be 50 to 150 nanometers, such as 50 nanometers, 80 nanometers, 100 nanometers or 150 nanometers, etc., so as to further improve the light extraction efficiency.

[0087] In order to facilitate the electrical connection between the auxiliary electrode layer 140 and the second electrode 123, the light extraction layer 130 can be patterned, that is, it has an opening area 133 exposing the second electrode 123, so that the auxiliary electrode layer 140 can be electrically connected to the second electrode 123 from the opening area 133, which is equivalent to connecting the auxiliary electrode layer 140 and the second electrode 123 in parallel, effectively reducing the resistance of the second electrode 123.

[0088] There are many ways to set the light extraction layer 130. This article mainly lists the following exemplary embodiments for illustration. It should be noted that in addition to the listed setting methods, other applicable setting methods can also be used, and the present disclosure does not limit this.

[0089] In some exemplary embodiments, a corresponding light extraction layer 130 may be provided for each sub-pixel, that is, the orthographic projection of the light extraction layer 130 on the substrate 100 at least partially overlaps with the orthographic projection of each sub-pixel on the substrate 100. It should be noted that there are many ways to define the orthographic projection range of the sub-pixel on the substrate 100, for example, it can be defined by the pixel opening corresponding to the sub-pixel, such as the orthographic projection edge of the upper port of the pixel opening (i.e., the end of the pixel opening relatively far from the first electrode 121) on the substrate substrate 100 can be used to define the orthographic projection range of the sub-pixel on the substrate substrate 100, which can be determined according to actual needs, and the present disclosure does not limit this.

[0090] For example, the light extraction layer 130 may include: a plurality of light extraction units 1301, and the above-mentioned opening area 133 is provided between adjacent light extraction units 1301. At this time, the opening area 133 may be a mesh opening area, that is, the opening areas 133 between the light extraction units 1301 are interconnected. The auxiliary electrode layer 140 covers the plurality of light extraction units 1301 and the opening areas 133 between the adjacent light extraction units 1301, and contacts the exposed second electrode 123 at the bottom of the opening area 133 to achieve electrical connection between the auxiliary electrode layer 140 and the second electrode 123.

[0091] For example, Figure 2 As shown, each light extraction unit 1301 may cover a corresponding sub-pixel. For example, the above-mentioned multiple sub-pixels include a first sub-pixel, a second sub-pixel and a third sub-pixel, and the multiple light extraction units 1301 may include a first light extraction unit, a second light extraction unit and a third light extraction unit. The orthographic projection of the first sub-pixel on the substrate substrate 100 is located within the orthographic projection range of the first light extraction unit on the substrate substrate 100, the orthographic projection of the second sub-pixel on the substrate substrate 100 is located within the orthographic projection range of the second light extraction unit on the substrate substrate 100, and the orthographic projection of the third sub-pixel on the substrate substrate 100 is located within the orthographic projection range of the third light extraction unit on the substrate substrate 100, thereby improving the light extraction efficiency of the first sub-pixel, the second sub-pixel and the third sub-pixel through the mutually independent light extraction units 1301.

[0092] It should be noted that the thicknesses of the first light extraction unit, the second light extraction unit and the third light extraction unit in the direction perpendicular to the base substrate 100 may be the same, or may be different.

[0093] For example, Figure 2As shown, the light extraction layer 130 may include a first sub-light extraction layer 131 and a second sub-light extraction layer 132, and the light extraction layer 130 is further divided into a first light extraction unit, a second light extraction unit and a third light extraction unit, and the auxiliary electrode layer 140 covers the light extraction layer 130 and the opening area 133 of the light extraction layer 130, and is electrically connected to the second electrode 123 exposed at the opening area 133. At this time, the light emitted from the second electrode 123 side of the first sub-pixel first passes through the first sub-light extraction layer 131 and the second sub-light extraction layer 132 at the first light extraction unit, and then passes through the auxiliary electrode layer 140 to be emitted; the light emitted from the second electrode 123 side of the second sub-pixel first passes through the first sub-light extraction layer 131 and the second sub-light extraction layer 132 at the second light extraction unit, and then passes through the auxiliary electrode layer 140 to be emitted; the light emitted from the second electrode 123 side of the third sub-pixel first passes through the first sub-light extraction layer 131 and the second sub-light extraction layer 132 at the third light extraction unit, and then passes through the auxiliary electrode layer 140 to be emitted.

[0094] Considering that a gap is reserved between each pixel, the process is difficult to implement and the process is complicated. Usually, three high-precision metal masks are required to realize the evaporation of the light extraction layer 130 above the first sub-pixel, the second sub-pixel and the third sub-pixel respectively. In some optional embodiments, each light extraction unit 1301 can cover multiple sub-pixels. Figure 3 Schematic diagram showing the layout of the light extraction unit in some embodiments of the present disclosure, Figure 4 FIG. 2 shows a schematic diagram of the layout of a light extraction unit according to another embodiment of the present disclosure. Figure 3 As shown, each light extraction unit 1301 can cover two sub-pixels. Figure 4 As shown, each light extraction unit 1301 may cover three sub-pixels.

[0095] It should be noted that, in actual implementation, the number and shape of sub-pixels covered by the light extraction unit 1301 can be set according to the pixel arrangement adopted. The following mainly lists the arrangement of the light extraction layer 130 corresponding to two pixel arrangements as examples for illustration. In other embodiments, other pixel arrangements can also be adopted, and the arrangement and shape of the light extraction unit 1301 can be adaptively set, and the present disclosure does not limit this.

[0096] Figure 5 FIG. 1 shows a schematic diagram of an exemplary pixel arrangement. Figure 5 As shown, each pixel unit P may include: a first sub-pixel p1, a second sub-pixel p2 and a third sub-pixel p3, and the first sub-pixel p1, the second sub-pixel p2 and the third sub-pixel p3 are arranged in a Delta manner. It should be noted that: Figure 5 The sub-pixel shapes shown in FIG. 1 are for illustration only and are not intended to be limiting. For example, the sub-pixel shapes may be Figure 5 In addition to the circle shown in the figure, other shapes such as ellipse, square, triangle, pentagon or hexagon can be used, or shapes similar to ellipse, square, triangle, pentagon or hexagon can be used.

[0097] Considering that when the pixel unit P follows Figure 5 When the arrangement is shown in the schematic, the gaps between the first sub-pixel p1, the second sub-pixel p2 and the third sub-pixel p3 are small. If a light extraction unit 1301 is provided for each sub-pixel, the processing difficulty is very high. Therefore, in some exemplary embodiments, the processing difficulty of the light extraction layer 130 can be reduced. Figure 5 The pixel arrangement shown in the figure changes the pixel structure, and increases the spacing distance between adjacent sub-pixels by reducing the pixel aperture ratio of the sub-pixels, so as to facilitate the corresponding arrangement of each light extraction unit 1301. For example, the pixel aperture ratio of each sub-pixel can be reduced to Figure 5 50% to 80% of the pixel structure shown, such as 50%, 60%, 70% or 80%.

[0098] Figure 6 FIG. 2 shows a schematic plan view of a pixel structure and a light extraction layer in some embodiments of the present disclosure. Figure 6 As shown, in some exemplary embodiments, the first sub-pixel p1, the second sub-pixel p2, and the third sub-pixel p3 may include a first edge and a second edge disposed opposite to the first edge, the first edge is a straight line, and the second edge is a curve. The line connecting the center points of the first sub-pixel p1, the second sub-pixel p2, and the third sub-pixel p3 forms a triangle, the second edge of the first sub-pixel p1 is disposed opposite to the second edge of the second sub-pixel p2, and the second edge of the third sub-pixel p3 is disposed toward the first sub-pixel p1 and the second sub-pixel p2. For example, Figure 5 Based on the pixel structure shown, the opening area of ​​each sub-pixel is reduced by half. At this time, if the sub-pixel shape before the improvement is circular, then after the improvement, the plane shape of the first sub-pixel p1, the second sub-pixel p2 and the third sub-pixel p3 can be semi-circular; if the sub-pixel shape before the improvement is elliptical, then after the improvement, the plane shape of the first sub-pixel p1, the second sub-pixel p2 and the third sub-pixel p3 can be semi-elliptical. Of course, if the sub-pixel shape before the improvement is square, then after the improvement, the first sub-pixel p1, the second sub-pixel p2 and the third sub-pixel p3 can be square with a reduced area.

[0099] At this time, in order to further reduce the processing difficulty of the light extraction layer 130, as shown in FIG. Figure 6As shown, each light extraction unit 1301 can cover a pixel unit P. For example, multiple pixel units P and multiple light extraction units 1301 can be arranged in a one-to-one correspondence, and the orthographic projection of each sub-pixel included in each pixel unit P on the base substrate 100 can be located within the orthographic projection range of the corresponding light extraction unit 1301 on the base substrate 100. At this time, the opening area 133 located between adjacent light extraction units 1301 can be as follows Figure 6 The mesh opening area shown in .

[0100] For example, Figure 6 As shown, the planar shape of the light extraction unit 1301 can be a hexagon, which includes: a first side, a second side, a third side, a fourth side, a fifth side and a sixth side connected in sequence. The first side is arranged opposite to the fourth side, the second side is arranged opposite to the sixth side, and the third side is arranged opposite to the fifth side; the length of the first side is less than the length of the fourth side, and the extension direction of the fourth side is parallel to the arrangement direction of the first sub-pixel p1 and the second sub-pixel p2; the first edge of the first sub-pixel p1 and the first edge of the second sub-pixel p2 are arranged opposite to the third side and the fifth side respectively, and the first edge of the third sub-pixel p3 is arranged opposite to the first side. Of course, in addition to Figure 6 In addition to the planar shape shown, in other embodiments, the planar shape of the light extraction unit 1301 may also be other shapes such as a triangle, a diamond, a circle, or an ellipse, etc., and the present disclosure does not limit this.

[0101] For example, according to Figure 5 In the pixel arrangement shown, for the same column of pixel units P, the third sub-pixel p3 is on the same side of the line connecting the centers of the first sub-pixel p1 and the second sub-pixel p2, and for two adjacent columns of pixel units P, the third sub-pixel p3 is on different sides of the line connecting the centers of the first sub-pixel p1 and the second sub-pixel p2. Accordingly, for the same column of light extraction units 1301 arranged along the pixel column direction, the first sides are oriented in the same direction, and the first sides of the light extraction units 1301 in two adjacent columns are oriented in opposite directions.

[0102] Figure 7 Another exemplary pixel arrangement schematic diagram is shown. Figure 7As shown, each pixel unit P includes: a first sub-pixel p1, two second sub-pixels p2 and a third sub-pixel p3. In the same pixel unit P, the center points of the first sub-pixel p1, the two second sub-pixels p2 and the third sub-pixel p3 are connected in a rhombus. The area of ​​the second sub-pixel p2 is smaller than the area of ​​the first sub-pixel p1 and the area of ​​the third sub-pixel p3. The area of ​​the first sub-pixel p1 can be less than or equal to the area of ​​the third sub-pixel p3. For example, the first sub-pixel p1 is a red sub-pixel, the second sub-pixel p2 is a green sub-pixel, and the third sub-pixel p3 is a blue sub-pixel. It should be noted that the first sub-pixel p1 and the third sub-pixel p3 can be as follows Figure 7 The second sub-pixel p2 may be as shown in FIG. Figure 7 The ellipse shown, or the first sub-pixel p1, the second sub-pixel p2 and the third sub-pixel p3 may also adopt other shapes, such as triangle, circle, pentagon or hexagon, etc., which can be set according to actual needs and the present disclosure does not limit this.

[0103] The spacing between adjacent first sub-pixels p1 and third sub-pixels p3 is a first distance, the spacing between adjacent second sub-pixels p2 is a second distance, the spacing between adjacent first sub-pixels p1 and second sub-pixels p2 is a third distance, the spacing between adjacent second sub-pixels p2 and third sub-pixels p3 is a fourth distance, and the first distance and the second distance are greater than the third distance and the fourth distance.

[0104] Taking into account Figure 7 In the pixel arrangement method adopted in the invention, there are relatively large gaps between some sub-pixels. Therefore, when the light extraction layer 130 is arranged, the opening areas 133 of the adjacent light extraction units 1301 can be arranged correspondingly at the positions where these gaps are relatively large. Figure 8 FIG. 1 shows a schematic plan view of a pixel structure and a light extraction layer 130 of some embodiments of the present disclosure. Figure 8 As shown, the light extraction unit 1301 may be a bent strip structure. Among the above-mentioned multiple light extraction units 1301, at least a part of the light extraction units 1301 covers a first sub-pixel p1, a second sub-pixel p2 and a third sub-pixel p3, and at least a part of the light extraction units 1301 covers a first sub-pixel p1, two second sub-pixels p2 and a third sub-pixel p3. At this time, the above-mentioned opening area 133 located between adjacent light extraction units 1301 may be as follows Figure 8 The mesh opening area shown in .

[0105] Furthermore, the inventors have found through research that from the absorption spectrum of the second electrode 123, short-wave bands such as blue light bands absorb more than long-wave bands such as red light bands. Taking the red sub-pixel that emits red light as an example, directly setting the auxiliary electrode layer 140 on the second electrode 123 of the red sub-pixel without setting the light extraction layer 130 can also improve the luminous efficiency. The reason is that although the auxiliary electrode layer 140 is set on the second electrode 123, the reflectivity of the second electrode 123 is increased, this part of the increased reflected light can enhance the microcavity effect of the electroluminescent device 120, thereby improving the luminous efficiency.

[0106] Therefore, in some exemplary embodiments, the light emission wavelength of the first sub-pixel is greater than the light emission wavelengths of the second sub-pixel and the third sub-pixel. Then, the orthographic projection of the light extraction layer 130 on the substrate substrate 100 may at least partially overlap with the orthographic projection of the second sub-pixel on the substrate substrate 100; and / or, the orthographic projection of the light extraction layer 130 on the substrate substrate 100 may at least partially overlap with the orthographic projection of the third sub-pixel on the substrate substrate 100, thereby increasing the light extraction efficiency of the second sub-pixel and / or the third sub-pixel by setting the light extraction layer 130. As for the first sub-pixel, it can be as follows Figure 2 As shown in , the light extraction layer 130 is also provided correspondingly, so as to more comprehensively protect the second electrode 123 of each sub-pixel. Alternatively, the light extraction layer 130 need not be covered above the first sub-pixel, that is, the opening area of ​​the light extraction layer 130 is provided at a position directly opposite to the first sub-pixel, so that the auxiliary electrode layer 140 is in direct contact with the second electrode 123. On the one hand, the microcavity effect can be enhanced to improve the luminous efficiency, and on the other hand, the electrical connection between the auxiliary electrode layer 140 and the second electrode 123 can be achieved, the resistance of the second electrode is reduced, and it is also conducive to reducing the difficulty of the process.

[0107] Fig. 9 A schematic diagram of the stacked structure of a display substrate in some embodiments of the present disclosure is shown. Fig.10 Shows Fig. 9 A schematic plan view of a display substrate, wherein: Fig. 9 for Fig.10 The cross-sectional view obtained along the AA section line in . For example, Fig. 9 and Fig.10 As shown, the light extraction layer 130 (as shown Fig.10The dot-filled area in the image may cover the second sub-pixel p2 and the third sub-pixel p3, while the light extraction layer 130 is not covered above the first sub-pixel p1, that is, the opening area 133 of the light extraction layer 130 is set at the position corresponding to the first sub-pixel. For example, the orthographic projections of the second sub-pixel p2 and the third sub-pixel p3 on the base substrate 100 may be located within the orthographic projection of the light extraction layer 130 on the base substrate 100. For example, the first sub-pixel p1 may be a red sub-pixel, and one of the second sub-pixel p2 and the third sub-pixel p3 may be a green sub-pixel, and the other may be a blue sub-pixel.

[0108] For example, the orthographic projection of the opening area 133 of the light extraction layer 130 on the base substrate 100 at least partially overlaps with the orthographic projection of the first sub-pixel on the base substrate 100. In this case, the light extraction layer 130 has a plurality of opening areas 133 that are independent and spaced apart from each other, and the auxiliary electrode layer 140 can cover these opening areas 133 and contact the second electrode 123 exposed at the opening areas 133, thereby achieving electrical connection between the two. Fig.10 As shown, the orthographic projection of the first sub-pixel p1 on the substrate 100 may be located within the orthographic projection of the opening area 133 on the substrate 100. For example, the shape and size of the opening area 133 may be set according to the shape and size of the first sub-pixel p1.

[0109] like Fig. 9 As shown, the light extraction layer 130 may include a first sub-light extraction layer 131 and a second sub-light extraction layer 132. The light emitted from the second electrode 123 side of the second sub-pixel and the third sub-pixel passes through the first sub-light extraction layer 131, the second sub-light extraction layer 132 and the auxiliary electrode layer 140 in sequence, while the light emitted from the second electrode 123 side of the first sub-pixel passes through the auxiliary electrode layer 140.

[0110] For example, Fig. 9 As shown, the thickness of the light extraction layer 130 covering the second sub-pixel and the light extraction layer 130 covering the third sub-pixel can be set to be the same. At this time, in addition to covering the second sub-pixel and the third sub-pixel, the light extraction layer 130 also covers the spacing area between the second sub-pixel and the third sub-pixel. For example, the thickness of the first sub-light extraction layer 131 can be 50 to 100 nanometers, such as 50 nanometers, 60 nanometers, 80 nanometers or 100 nanometers; the thickness of the second sub-light extraction layer 132 can be 50 to 150 nanometers, such as 50 nanometers, 80 nanometers, 100 nanometers or 150 nanometers, so as to further improve the light extraction efficiency.

[0111] For example, the thickness of the light extraction layer 130 can also be set according to the luminous color of the covered sub-pixel, that is, the thickness of the light extraction layer 130 covering the second sub-pixel is different from that of the light extraction layer 130 covering the third sub-pixel, so as to specifically improve the light extraction efficiency of sub-pixels of different colors. Fig.11 A schematic diagram of the stacked structure of a display substrate according to some embodiments of the present disclosure is shown. Fig.11 In the example, the first sub-pixel is a red sub-pixel, the second sub-pixel is a green sub-pixel, and the third sub-pixel is a blue sub-pixel. The light extraction layer 130 is not covered on the first sub-pixel, and the thickness of the light extraction layer 130 covered on the third sub-pixel can be less than the thickness of the light extraction layer 130 covered on the second sub-pixel. For example, the thickness of the first sub-light extraction layer 131 covered on the second sub-pixel can be 80 to 100 nanometers, such as 80 nanometers, 90 nanometers or 100 nanometers, and the thickness of the second light extraction layer 130 can be 80 to 100 nanometers, such as 80 nanometers, 90 nanometers or 100 nanometers; and the thickness of the first sub-light extraction layer 131 covered on the third sub-pixel can be 60 to 80 nanometers, such as 60 nanometers, 70 nanometers or 80 nanometers, and the thickness of the second sub-light extraction layer 132 can be 80 to 100 nanometers, such as 80 nanometers, 90 nanometers or 100 nanometers.

[0112] like Figure 2 as well as Fig. 9 As shown, the auxiliary electrode layer 140 is disposed on the side of the light extraction layer 130 away from the second electrode 123, and the auxiliary electrode layer 140 is electrically connected to the second electrode 123 through the opening area 133 to reduce the resistance of the second electrode 123. The auxiliary electrode layer 140 and the second electrode 123 overlap in their orthographic projections on the base substrate 100.

[0113] In some example embodiments, the auxiliary electrode layer 140 can be a single film layer structure, and the auxiliary electrode layer 140 is stacked on the side of the light extraction layer 130 away from the base substrate 100, covering the first sub-pixel, the second sub-pixel, the third sub-pixel and the spacing area between the sub-pixels, and is electrically connected to the second electrode 123 at the opening area 133 of the light extraction layer 130.

[0114] For example, the auxiliary electrode layer 140 may be made of a transparent conductive material, so that the auxiliary electrode layer 140 has both conductivity and light transmittance, so as to reduce the resistance of the second electrode 123 while minimizing the loss of luminous efficiency caused by the auxiliary electrode layer 140. For example, the auxiliary electrode layer 140 may be made of an oxide semiconductor material, such as indium zinc oxide (IZO), indium tin oxide (ITO), indium gallium zinc oxide (IGZO) or aluminum-doped zinc oxide (AZO). For example, the thickness of the auxiliary electrode layer 140 may be 100 to 1000 nanometers, and the transmittance of the auxiliary electrode layer 140 is greater than 90% for light with a wavelength of 532 nm.

[0115] In some example embodiments, the auxiliary electrode layer 140 may also be a multi-layer film structure, and the auxiliary electrode layer 140 may include a plurality of transparent conductive layers stacked and electrically connected to each other, and the plurality of transparent conductive layers are sequentially arranged in a direction away from the base substrate 100. The auxiliary electrode layer 140 composed of a plurality of transparent conductive layers can further reduce the resistance of the second electrode 123.

[0116] In addition, the inventors have discovered through research that by adapting the thickness of the auxiliary electrode layer 140 to the thickness of the light extraction layer 130, the auxiliary electrode layer 140 can not only reduce the resistance of the second electrode 123, but also cooperate with the light extraction layer 130 to adjust the path of light and extract more display light, thereby improving the luminous efficiency of the device.

[0117] In order to obtain a suitable thickness range, the inventors conducted a comparative test during the research process, taking the first sub-pixel as a red sub-pixel, the second sub-pixel as a green sub-pixel, the third sub-pixel as a blue sub-pixel, and the auxiliary electrode layer 140 as indium zinc oxide (IZO) as an example. The reference device of the comparative test is a device provided with a light extraction layer 130 such as a first sub-light extraction layer 131 and a second sub-light extraction layer 132, but without an auxiliary electrode layer 140. At this time, the thickness of the first sub-light extraction layer 131 and the second sub-light extraction layer 132 is a thickness that simply considers the light extraction efficiency without considering the light regulation in cooperation with the auxiliary electrode layer 140. First test the luminous efficiency of the reference device, that is, the electro-optical conversion efficiency, and normalize the luminous efficiency of the reference device to 100% for comparison.

[0118] Then, on the basis of the reference device, an auxiliary electrode layer 140 is provided above the first sub-light extraction layer 131 and the second sub-light extraction layer 132, and the thickness of the first sub-light extraction layer 131, the thickness of the second sub-light extraction layer 132 and the thickness of the auxiliary electrode layer 140 are comprehensively adjusted for the purpose of improving the luminous efficiency compared with the reference device. The above comparative test results are described below by taking the several exemplary embodiments provided above as examples.

[0119] The first set of comparative experiments corresponds to Figure 2 The illustrated embodiment. Fig.12 The test result diagram of the first group of comparative tests is shown, where the abscissa is the thickness of the auxiliary electrode layer 140 in nanometers, and the ordinate is the luminous efficiency. For example, the light extraction layers 130 of different color sub-pixels in the reference device have the same thickness, the first sub-light extraction layer 131 has a thickness of 80 nanometers, and the second sub-light extraction layer 132 has a thickness of 60 nanometers. Fig.12 The dashed line L0 in the figure represents the luminous efficiency of the reference device (100%), and the curve L R Represents the red light efficiency curve, curve LG Indicates the green light efficiency curve and curve L B Represents the blue light efficiency curve. Fig.12 It can be seen that within a certain range of the thickness of the auxiliary electrode layer 140, as the thickness of the auxiliary electrode layer 140 increases, the red light luminous efficiency first decreases and then increases; the green light luminous efficiency increases and then decreases, and the blue light luminous efficiency continues to decrease. Compared with the reference device, by setting the auxiliary electrode layer 140 and adjusting the thickness of the light extraction layer 130 and the thickness of the auxiliary electrode layer 140, the luminous efficiency of the red sub-pixel can be increased by 20%, and the luminous efficiency of the blue sub-pixel and the green sub-pixel can be increased by 2%, which is beneficial to improving the luminous efficiency of the display substrate 10.

[0120] The second group of comparative experiments corresponds to Fig. 9 The illustrated embodiment. Fig.13 The test results of the second group of comparative tests are shown in FIG. Fig.13 It can be seen that there is no need to set the light extraction layer 130 above the red sub-pixel. Under the action of the auxiliary electrode layer 140, the function of increasing light extraction can also be achieved, so that the luminous efficiency can be improved. Within a certain range of the thickness of the auxiliary electrode layer 140, as the thickness of the auxiliary electrode layer 140 increases, the red light luminous efficiency shows a trend of continuous decrease; the green light luminous efficiency shows a trend of increasing and then decreasing, and the blue light luminous efficiency shows a trend of continuous decrease. Compared with the reference device, by setting the auxiliary electrode layer 140 and adjusting the thickness of the light extraction layer 130 covering the green sub-pixel and the blue sub-pixel and the thickness of the auxiliary electrode layer 140 above each sub-pixel, the luminous efficiency of the red sub-pixel can be increased by 15-20%, the luminous efficiency of the green sub-pixel can be increased by about 2%, and the luminous efficiency of the blue sub-pixel can change by ±2%, which is beneficial to improve the luminous efficiency of the display substrate 10.

[0121] The third group of comparative experiments corresponds to Fig.11 The illustrated embodiment. Fig.14 The test results of the third group of comparative tests are shown in FIG. Fig.14 It can be seen from the figure that by differentially setting the thickness of the light extraction layer 130 covering the green sub-pixel and the blue sub-pixel, it is beneficial to improve the luminous efficiency of the green sub-pixel and the blue sub-pixel as a whole. Fig.14 As shown, compared with the reference device, by setting an auxiliary electrode layer 140, and adjusting the thickness of the light extraction layer 130 covering the green sub-pixel and the blue sub-pixel differently, and adjusting the thickness of the auxiliary electrode layer 140, the luminous efficiency of the red sub-pixel can be increased by 15-21%, the luminous efficiency of the green sub-pixel can be increased by about 4%-6%, and the luminous efficiency of the blue sub-pixel can be increased by -1%-4%, which is beneficial to improving the luminous efficiency of the display substrate 10.

[0122] Based on the above research, it is found that as the thickness of the auxiliary electrode layer 140 increases, there are differences in the change trends of the luminous efficiency of sub-pixels of different colors. Therefore, the thickness of the auxiliary electrode layer 140 area corresponding to sub-pixels of different colors can be set differently to further improve the luminous efficiency of each sub-pixel while reducing the resistance of the second electrode 123, thereby improving the luminous efficiency of the display substrate 10.

[0123] Fig.15 FIG. 1 shows a schematic diagram of the stacked structure of the display substrate 10 of some embodiments of the present disclosure. Fig.15 As shown, in some example embodiments, the first sub-pixel is a red sub-pixel, the second sub-pixel is a green sub-pixel, and the third sub-pixel is a blue sub-pixel, and the auxiliary electrode layer 140 may include: a first region 1401 corresponding to the first sub-pixel, a second region 1402 corresponding to the second sub-pixel, and a third region 1403 corresponding to the third sub-pixel. The thickness of the third region 1403 is less than the thickness of the second region 1402, and the thickness of the first region 1401 is less than or equal to the thickness of the second region 1402. For example, the thickness of the first region 1401 may be 100 to 150 nanometers, such as 100 nanometers, 110 nanometers, 130 nanometers, 140 nanometers, or 150 nanometers, etc., the thickness of the second region 1402 may be 250 to 350 nanometers, such as 250 nanometers, 300 nanometers, or 350 nanometers, etc., and the thickness of the third region 1403 may be 100 to 150 nanometers, such as 100 nanometers, 110 nanometers, 130 nanometers, 140 nanometers, or 150 nanometers, etc. The thickness of the first region 1401 and the third region 1403 may be the same, or may be different, and may be set according to actual needs.

[0124] For example, during the preparation process, a transparent conductive film with a thickness of 250 to 350 nanometers can be formed first, and then the transparent conductive film above the red sub-pixel and the transparent conductive film above the blue sub-pixel can be etched by an etching process to reduce the thickness of the transparent conductive film above the red sub-pixel and the blue sub-pixel to 100 to 150 nanometers, thereby obtaining the auxiliary electrode layer 140.

[0125] In order to verify the effect of setting the thickness of the auxiliary electrode layer 140 differently, Fig.15 The illustrated embodiment was subjected to a fourth set of comparative tests. Fig.16 The test results of the fourth group of comparative tests are shown in FIG. Fig.16As shown, compared with the reference device, when the thickness of the first region 1401 is 120 nanometers, the thickness of the second region 1402 is 300 nanometers, and the thickness of the third region 1403 is 100 nanometers, the luminous efficiency of the red sub-pixel R can be increased by 16%, the luminous efficiency of the green sub-pixel G can be increased by about 5%, and the luminous efficiency of the blue sub-pixel B can be increased by 2%, which is beneficial to improve the luminous efficiency of the display substrate 10.

[0126] In addition, the number of the light extraction layer 130 and the auxiliary electrode layer 140 included in the display substrate 10 can be set according to actual needs. Figure 2 , Fig. 9 , Fig.11 as well as Fig.15 In the corresponding embodiment, the display substrate 10 includes a light extraction layer 130 and an auxiliary electrode layer 140. In other exemplary embodiments, the display substrate 10 may also include multiple light extraction layers 130 and multiple auxiliary electrode layers 140, and the multiple light extraction layers 130 and the multiple auxiliary electrode layers 140 are staggered and stacked on the side of the second electrode 123 away from the base substrate 100, so as to reduce the resistance of the second electrode 123 while improving the luminous efficiency of the light-emitting substrate.

[0127] Optionally, in order to minimize the thickness of the display substrate 10, the thickness of each layer structure in the scheme of multiple light extraction layers 130 and multiple auxiliary electrode layers 140 can be reduced compared to the scheme of a single light extraction layer 130 and a single auxiliary electrode layer 140. For example, if the display substrate 10 includes m light extraction layers 130 and m auxiliary electrode layers 140 (m is an integer greater than or equal to 2) arranged in an alternating stack, the thickness of each layer can be reduced to one-mth of that when a single light extraction layer 130 and a single auxiliary electrode layer 140 are provided.

[0128] Fig.17 Schematic diagram of the stacked structure of the display substrate 10 of some embodiments of the present disclosure is shown. Fig.17As shown, the display substrate 10 may include two light extraction layers 130a, 130b and two auxiliary electrode layers 140a, 140b, and the two light extraction layers 130a, 130b and the two auxiliary electrode layers 140a, 140b are arranged in an alternately stacked manner in the order of first arranging the light extraction layer 130 and then arranging the auxiliary electrode layer 140 in a direction away from the base substrate 100. The light extraction layers 130a and 130b are arranged corresponding to the second sub-pixel and the third sub-pixel, and include a first sub-light extraction layer 131 and a second sub-light extraction layer 132. Both the light extraction layer 130a and the light extraction layer 130b are provided with an opening area 133 above the first sub-pixel, the auxiliary electrode layer 140a covers the light extraction layer 130a and contacts the exposed second electrode 123 at the opening area 133 to achieve electrical connection, and the auxiliary electrode layer 140b covers the light extraction layer 130b and contacts the exposed auxiliary electrode layer 140a at the opening area 133 to achieve electrical connection.

[0129] In some exemplary embodiments, the display substrate 10 further includes: an encapsulation layer (not shown in the figure), which is arranged on the side of the auxiliary electrode layer 140 away from the base substrate 100 to encapsulate the electroluminescent device 120 of each sub-pixel and prevent water and oxygen from corroding and damaging the device.

[0130] For example, the encapsulation layer may include a first encapsulation layer, a second encapsulation layer, and a third encapsulation layer which are stacked in sequence. The first encapsulation layer and the third encapsulation layer may be inorganic encapsulation layers, for example, inorganic materials such as nitrides, oxides, oxynitrides, nitrates, carbides, or any combination thereof may be used, and the preparation process may adopt a chemical vapor deposition (CVD) process. The second encapsulation layer may be an organic encapsulation layer, for example, organic materials such as acrylic, hexamethyldisiloxane, polyacrylates, polycarbonates, polystyrene, etc. may be used, and the preparation process may adopt an inkjet printing (IJP) process. For example, the refractive index of the first encapsulation layer may be greater than the refractive index of the second sub-light extraction layer 132, and less than the refractive index of the first sub-light extraction layer 131, so as to further improve the luminous efficiency of the display substrate 10. For example, the refractive index of the first encapsulation layer can be 1.5-1.9, such as 1.5, 1.6, 1.7 or 1.9, the refractive index of the second encapsulation layer can be 1.2-1.6, such as 1.2, 1.4 or 1.6, and the refractive index of the third encapsulation layer can be 1.5, 1.6, 1.7 or 1.9.

[0131] Of course, in other embodiments, the display substrate 10 may also include other film layer structures, such as but not limited to a touch layer (not shown in the figure) for providing a touch function, a color film layer (or polarizer) (not shown in the figure), and a cover layer (not shown in the figure) for protecting the display substrate 10, etc., which can be configured according to the needs of the actual application scenario, and the present disclosure does not impose any restrictions on this.

[0132] in addition, Fig.18 Schematic diagram of the structure of the display device of some embodiments of the present disclosure is shown. Fig.18 As shown, some embodiments of the present disclosure provide a display device 20, including the display substrate 10 provided in any of the above embodiments. The display device 20 can be, for example, a display, a television, a tablet computer, a laptop computer, a mobile phone, a digital photo frame, a navigator, or any other product or component with a display function. Of course, the display device 20 provided in the embodiments of the present disclosure is not limited to the types listed above.

[0133] It should be noted that the drawings of the embodiments of the present disclosure only relate to the structures related to the embodiments of the present disclosure, and other structures can refer to the general design. In the absence of conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0134] Although some embodiments of the present disclosure 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 embodiment and all changes and modifications falling within the scope of the present disclosure.

Claims

1. A display substrate, characterized in that: include: substrate substrate; A plurality of pixel units arranged in an array, each pixel unit comprising a plurality of sub-pixels, each sub-pixel comprising: a first electrode, a light-emitting functional layer and a second electrode stacked on the substrate; A light extraction layer is disposed on a side of the second electrode away from the base substrate, and the light extraction layer has an opening area exposing the second electrode; an auxiliary electrode layer, disposed on a side of the light extraction layer away from the second electrode, the auxiliary electrode layer and the orthographic projection of the second electrode on the base substrate at least partially overlap, and the auxiliary electrode layer is electrically connected to the second electrode through the opening area; At least a portion of the light emitted by the sub-pixel is incident on the auxiliary electrode layer through the light extraction layer, and then transmitted from the auxiliary electrode layer.

2. The display substrate according to claim 1, characterized in that: The plurality of sub-pixels include a first sub-pixel, a second sub-pixel and a third sub-pixel, wherein the light emission wavelength of the first sub-pixel is greater than the light emission wavelengths of the second sub-pixel and the third sub-pixel; The orthographic projection of the light extraction layer on the base substrate at least partially overlaps with the orthographic projection of the second sub-pixel on the base substrate; and / or The orthographic projection of the light extraction layer on the base substrate at least partially overlaps with the orthographic projection of the third sub-pixel on the base substrate.

3. The display substrate according to claim 2, characterized in that: The orthographic projections of the second sub-pixel and the third sub-pixel on the base substrate are located within the orthographic projection range of the light extraction layer on the base substrate.

4. The display substrate according to claim 2, characterized in that: The orthographic projection of the opening area on the base substrate at least partially overlaps with the orthographic projection of the first sub-pixel on the base substrate, and the auxiliary electrode layer covers the opening area and contacts the second electrode exposed in the opening area.

5. The display substrate according to claim 4, characterized in that: The orthographic projection of the first sub-pixel on the base substrate is located within the orthographic projection range of the opening area on the base substrate.

6. The display substrate according to claim 2, characterized in that: The first sub-pixel is a red sub-pixel, the second sub-pixel is a green sub-pixel, and the third sub-pixel is a blue sub-pixel.

7. The display substrate according to any one of claims 1 to 6, characterized in that: The thickness of the light extraction layer corresponding to the sub-pixels of different colors is the same, or the thickness of the light extraction layer corresponding to the sub-pixels of different colors is different.

8. The display substrate according to any one of claims 1 to 6, characterized in that: The light extraction layer includes: a first sub-light extraction layer and a second sub-light extraction layer which are stacked, wherein the first sub-light extraction layer is closer to the second electrode than the second sub-light extraction layer, and the refractive index of the first sub-light extraction layer is greater than the refractive index of the second sub-light extraction layer.

9. The display substrate according to claim 8, characterized in that: The thickness of the first sub-light extraction layer is 50 to 100 nanometers, the thickness of the second sub-light extraction layer is 50 to 150 nanometers, and the thickness of the auxiliary electrode layer is 100 to 1000 nanometers.

10. The display substrate according to claim 2, characterized in that: The first sub-pixel is a red sub-pixel, the second sub-pixel is a green sub-pixel, and the third sub-pixel is a blue sub-pixel; The auxiliary electrode layer includes: a first area corresponding to the first sub-pixel, a second area corresponding to the second sub-pixel, and a third area corresponding to the third sub-pixel; Along a direction perpendicular to the substrate, the thickness of the third region is smaller than the thickness of the second region, and the thickness of the first region is smaller than or equal to the thickness of the second region.

11. The display substrate according to claim 10, characterized in that: In a direction perpendicular to the substrate, the thickness of the first region is 100-150 nanometers, the thickness of the second region is 250-350 nanometers, and the thickness of the third region is 100-150 nanometers.

12. The display substrate according to any one of claims 1 to 3, characterized in that: The light extraction layer includes: a plurality of light extraction units, the opening area is provided between adjacent light extraction units, and each of the light extraction units covers one sub-pixel or a plurality of sub-pixels.

13. The display substrate according to claim 12, characterized in that: Each of the light extraction units covers one of the pixel units.

14. The display substrate according to claim 13, characterized in that: The pixel unit comprises: a first sub-pixel, a second sub-pixel and a third sub-pixel, wherein the first sub-pixel, the second sub-pixel and the third sub-pixel comprise a first edge and a second edge arranged opposite to the first edge, the first edge is a straight line, and the second edge is a curve; The center points of the first sub-pixel, the second sub-pixel and the third sub-pixel are connected to form a triangle, the second edge of the first sub-pixel is arranged opposite to the second edge of the second sub-pixel, and the second edge of the third sub-pixel is arranged toward the first sub-pixel and the second sub-pixel.

15. The display substrate according to claim 14, characterized in that: The planar shapes of the first sub-pixel, the second sub-pixel and the third sub-pixel are circular, semi-circular or semi-elliptical.

16. The display substrate according to claim 14, characterized in that: The planar shape of the light extraction unit is a hexagon, and the hexagon includes: a first side, a second side, a third side, a fourth side, a fifth side and a sixth side connected in sequence, the first side is arranged opposite to the fourth side, the second side is arranged opposite to the sixth side, and the third side is arranged opposite to the fifth side; The length of the first side is smaller than the length of the fourth side, and the extension direction of the fourth side is parallel to the arrangement direction of the first sub-pixel and the second sub-pixel; The first edge of the first sub-pixel and the first edge of the second sub-pixel are respectively arranged opposite to the third side and the fifth side, and the first edge of the third sub-pixel is arranged opposite to the first side.

17. The display substrate according to claim 12, characterized in that: The pixel unit comprises: a first sub-pixel, two second sub-pixels and a third sub-pixel, the area of ​​the second sub-pixel is smaller than the area of ​​the first sub-pixel and the area of ​​the third sub-pixel, and the center points of the first sub-pixel, the two second sub-pixels and the third sub-pixel are connected in a rhombus shape; The spacing between adjacent first sub-pixels and the third sub-pixels is a first distance, the spacing between adjacent second sub-pixels is a second distance, the spacing between adjacent first sub-pixels and the second sub-pixels is a third distance, the spacing between adjacent second sub-pixels and the third sub-pixels is a fourth distance, and the first distance and the second distance are greater than the third distance and the fourth distance; The light extraction unit is a bent strip structure, and among the multiple light extraction units, at least a portion of the light extraction units covers one first sub-pixel, one second sub-pixel and one third sub-pixel, and at least a portion of the light extraction units covers one first sub-pixel, two second sub-pixels and one third sub-pixel.

18. The display substrate according to any one of claims 1 to 6, characterized in that: It comprises a plurality of the light extraction layers and a plurality of the auxiliary electrode layers, wherein the plurality of the light extraction layers and the plurality of the auxiliary electrode layers are alternately stacked and arranged on a side of the second electrode away from the base substrate.

19. The display substrate according to any one of claims 1 to 6, characterized in that: The first electrode is a reflective electrode, the second electrode is configured to partially transmit and partially reflect the light emitted by the light-emitting functional layer, and the second electrodes of adjacent sub-pixels are connected to each other.

20. The display substrate according to any one of claims 1 to 6, characterized in that: The second electrode comprises a metal material, and the auxiliary electrode layer comprises a transparent conductive material.

21. A display substrate, characterized in that: include: substrate substrate; A plurality of pixel units arranged in an array, each pixel unit comprising a first sub-pixel, a second sub-pixel and a third sub-pixel, the first sub-pixel being a red sub-pixel, and each sub-pixel comprising: a first electrode, a light-emitting functional layer and a second electrode stacked on the substrate; a light extraction layer, disposed on a side of the second electrode away from the base substrate, the light extraction layer covers the second sub-pixel and the third sub-pixel, and has an opening area exposing the second electrode of the first sub-pixel; an auxiliary electrode layer, disposed on a side of the light extraction layer away from the second electrode, the auxiliary electrode layer covering the light extraction layer and the opening area, and electrically connected to the exposed second electrode at the bottom of the opening area; The light emitted by the first sub-pixel is emitted through the auxiliary electrode layer, and the light emitted by the second sub-pixel and the third sub-pixel is emitted through the light extraction layer and the auxiliary electrode layer.

22. A display device, characterized in that: include: The display substrate according to any one of claims 1 to 21.

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