CN115347030A

CN115347030A - Display panel and display device

Info

Publication number: CN115347030A
Application number: CN202211027285.9A
Authority: CN
Inventors: 黄清雨; 王伟杰; 焦志强; 孙中元; 孙孟娜; 张娟; 王鹏
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2022-08-25
Filing date: 2022-08-25
Publication date: 2022-11-15

Abstract

The application discloses display panel and display device relates to and shows technical field. The display panel comprises a plurality of sub-pixels and a light extraction layer, wherein each sub-pixel comprises an anode layer, a functional film layer and a cathode layer which are sequentially stacked. The plurality of sub-pixels includes at least a sub-pixel of a first color and a sub-pixel of a second color. Because the difference value of the distances between the surface of the functional film layer far away from the substrate and the substrate in any two sub-pixels is smaller than the difference threshold value, the flatness of the surface of the cathode layer formed in the region where the sub-pixels with different colors are located is better, the probability of fracture of the cathode layer is reduced, and the display effect of the display panel is improved. Meanwhile, the thickness of the first part corresponding to the sub-pixel of the first color in the light extraction layer is different from the thickness of the second part corresponding to the sub-pixel of the second color, so that the thickness of the light extraction layer can meet the optical gain characteristic of the corresponding sub-pixel, and the luminous efficiency of the sub-pixel in the display panel is ensured.

Description

Display panel and display device

Technical Field

The present disclosure relates to display technologies, and particularly to a display panel and a display device.

Background

The display panel comprises a substrate base plate and a plurality of sub-pixels with different colors, wherein the sub-pixels are positioned on the substrate base plate, and each sub-pixel comprises: and the anode layer, the functional film layer and the cathode layer are positioned on the substrate and sequentially stacked.

In the related art, since the sub-pixels with different colors have different optical gain characteristics at different wavelengths, the thickness of the functional film layer of the sub-pixels with different colors needs to be designed differently to satisfy the light emitting efficiency of the sub-pixels with different colors. For example, the display panel includes a red sub-pixel, a green sub-pixel and a blue sub-pixel, and the thickness of the functional film layer of the red sub-pixel is greater than that of the functional film layer of the green sub-pixel, and the thickness of the functional film layer of the green sub-pixel is greater than that of the functional film layer of the blue sub-pixel.

However, since the functional film layers of the sub-pixels with different colors have different thicknesses, the distance between the surface of the functional film layer of the sub-pixel with different colors, which is far away from the substrate, and the substrate is different, that is, the surface for disposing the cathode layer has poor flatness, which easily causes the cathode layer to break, and the display effect of the display panel is poor.

Disclosure of Invention

The application provides a display panel and a display device, which can solve the problem that the display effect of the display panel is poor due to the fracture of a cathode layer in the related art. The technical scheme is as follows:

in one aspect, there is provided a display panel including:

a base substrate;

the array substrate comprises a substrate, a plurality of sub-pixels and a plurality of shielding layers, wherein the plurality of sub-pixels are positioned on one side of the substrate, each sub-pixel comprises an anode layer, a functional film layer and a cathode layer which are sequentially stacked, a micro cavity of the sub-pixel is formed in the area where each sub-pixel is positioned, and the plurality of sub-pixels at least comprise sub-pixels of a first color and sub-pixels of a second color;

and a light extraction layer located on a side of the plurality of sub-pixels away from the substrate base plate, the light extraction layer including at least a first portion and a second portion, an orthographic projection of the first portion on the substrate base plate at least partially overlapping an orthographic projection of the sub-pixels of the first color on the substrate base plate, an orthographic projection of the second portion on the substrate base plate at least partially overlapping an orthographic projection of the sub-pixels of the second color on the substrate base plate;

the difference value of the distances between the surface, away from the substrate base plate, of the functional film layers of any two of the sub-pixels and the substrate base plate is smaller than a difference threshold value, and the thickness of the first portion is different from that of the second portion.

Optionally, the microcavity length of the sub-pixel of the first color is greater than that of the sub-pixel of the second color, and the thickness of the first portion is greater than that of the second portion;

wherein, for each sub-pixel, the microcavity length of the sub-pixel is used to represent the distance between the surface of the anode layer far away from the substrate in the sub-pixel and the surface of the sub-pixel emitting light.

Optionally, the plurality of sub-pixels further includes a sub-pixel of a third color, and the light extraction layer further includes a third portion, and an orthographic projection of the third portion on the substrate base at least partially overlaps with an orthographic projection of the sub-pixel of the third color on the substrate base;

the third portion has a thickness different from the thickness of the first portion and different from the thickness of the second portion.

Optionally, the microcavity length of the sub-pixel of the second color is greater than the microcavity length of the sub-pixel of the third color, and the thickness of the second portion is greater than the thickness of the third portion.

Optionally, the first color is red, the second color is green, and the third color is blue.

Optionally, the functional film layer includes: the light-emitting diode comprises an electron injection layer, an electron transport layer, a light-emitting layer, an optical adjustment layer, a hole transport layer and a hole injection layer which are sequentially stacked along the direction far away from the substrate.

Optionally, the light emitting layer and the optical adjustment layer in the functional film layers of the plurality of sub-pixels are both patterned film layers;

the hole transport layer and the hole injection layer in the functional film layers of the plurality of sub-pixels are both shared film layers;

the electron injection layer and the electron transport layer in the functional film layers of the plurality of sub-pixels are both patterned film layers, or the electron injection layer and the electron transport layer in the functional film layers of the plurality of sub-pixels are both common film layers;

the patterned film layer comprises a plurality of patterns which are arranged at intervals, orthographic projections of the patterns on the substrate base plate are located in the areas where the sub-pixels are located and are not located in the interval areas of the sub-pixels, and orthographic projections of the shared film layer on the substrate base plate are located in the areas where the sub-pixels are located and are located in the interval areas of the sub-pixels.

Optionally, the functional film layer includes: the light-emitting diode comprises a substrate, and a first light-emitting layer, a second light-emitting layer, a first optical adjustment layer, a second electron injection layer, a second electron transport layer, a second light-emitting layer, a second optical adjustment layer, a second hole transport layer, a first electron injection layer, a first light-emitting layer, a first optical adjustment layer, a second electron transport layer, a second light-emitting layer, a second optical adjustment layer, a second hole transport layer and a hole injection layer which are sequentially stacked along a direction away from the substrate.

Optionally, the first light emitting layer, the first optical adjustment layer, the charge generation layer, the second light emitting layer and the second optical adjustment layer in the functional film layers of the plurality of sub-pixels are patterned film layers;

the first hole transport layer, the second electron injection layer, the second electron transport layer, the second hole transport layer and the hole injection layer in the functional film layers of the plurality of sub-pixels are all common film layers;

the first electron injection layer and the first electron transport layer in the functional film layers of the plurality of sub-pixels are both patterned film layers, or the first electron injection layer and the first electron transport layer in the functional film layers of the plurality of sub-pixels are both common film layers;

Optionally, the functional film layer includes: the light-emitting diode comprises a hole injection layer, a hole transport layer, a first light-emitting layer, a second light-emitting layer, a first hole blocking layer, a charge generation layer, a third light-emitting layer, a second hole blocking layer, an electron transport layer and an electron injection layer which are sequentially stacked along the direction far away from the substrate.

Optionally, the hole injection layer, the hole transport layer and the charge generation layer in the functional film layers of the plurality of sub-pixels are all patterned film layers;

the first light-emitting layer, the second light-emitting layer, the first hole blocking layer, the third light-emitting layer, the second hole blocking layer, the electron transport layer and the electron injection layer in the functional film layers of the plurality of sub-pixels are all shared film layers;

Optionally, the display panel further includes: the color film layer is positioned on one side of the plurality of sub-pixels far away from the substrate base plate;

the color film layer comprises a plurality of color blocking blocks with different colors, and the area of each sub-pixel is positioned in the orthographic projection of one color blocking block on the substrate.

Optionally, the cathode layer is made of indium zinc oxide.

Optionally, the display panel is a silicon-based display panel.

In another aspect, there is provided a display device including: a power supply assembly and a display panel as claimed in the above aspect;

the power supply assembly is used for supplying power to the display panel.

The beneficial effect that technical scheme that this application provided brought includes at least:

the application provides a display panel and display device, and this display panel includes a plurality of sub-pixels and light extraction layer, and every sub-pixel is including the anode layer, functional film layer and the cathode layer that stack gradually. The plurality of sub-pixels includes at least a sub-pixel of a first color and a sub-pixel of a second color. Because the difference value of the distances between the surface of the functional film layer far away from the substrate base plate and the substrate base plate in any two sub-pixels is smaller than the difference threshold value, the flatness of the surface of the cathode layer formed in the region where the sub-pixels with different colors are located is better, the probability of breakage of the cathode layer is reduced, and the display effect of the display panel is improved. Meanwhile, the thickness of the first part corresponding to the sub-pixel of the first color in the light extraction layer is different from the thickness of the second part corresponding to the sub-pixel of the second color, so that the thickness of the light extraction layer can meet the optical gain characteristic of the corresponding sub-pixel, and the luminous efficiency of the sub-pixel in the display panel is ensured.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a display panel in the related art;

fig. 2 is a schematic structural diagram of a display panel according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of another display panel provided in an embodiment of the present application;

fig. 4 is a schematic structural diagram of another display panel provided in the embodiment of the present application;

fig. 5 is a schematic structural diagram of another display panel provided in an embodiment of the present application;

fig. 6 is a schematic structural diagram of another display panel provided in an embodiment of the present application;

fig. 7 is a schematic structural diagram of a display device according to an embodiment of the present application.

Detailed Description

To make the objects, technical solutions and advantages of the present application more clear, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

In recent years, virtual Reality (VR) devices and Augmented Reality (AR) devices have been receiving market attention. Currently, the shipment of head-mounted devices (alternatively referred to as wearable display devices) is large, with a three-year composite growth rate of 96%. Current smartphones and televisions may eventually be replaced by more ergonomic smart-glasses style devices (i.e., head-mounted devices) that allow harmonious coexistence of the digital world as well as the analog world. Organic light-emitting diode (OLED) display panels have been key components developed for VR and AR devices. The existing mainstream VR and AR devices employ a silicon-based OLED (si-OLED) display panel, which is manufactured by a method different from that of an OLED panel having a large size of a smart phone or a television, and is formed by directly preparing OLEDs on a silicon substrate. The pixel density (PPI) of the pixels in the si-OLED display panel is higher and the size of the pixels is smaller. At present, the mature mass production technology of the si-OLED display panel is to use a white light emitting diode (WOLED) and a Color Filter (CF) to achieve a colorized display effect. Although the existing si-OLED display panel with pixel density can already meet the display requirements of some VR devices, the PPI and brightness levels of the existing micro OLED display panel are still low, and the requirements of AR devices and VR devices with higher end cannot be met. However, the conventional si-OLED display panel (WOLED + CF) has large light efficiency loss, low color gamut and poor display effect.

Compared with a si-OLED display panel (WOLED + CF), if the si-OLED display panel directly performs a patterning design (for example, a mask plate is used for performing patterning evaporation) on a light emitting layer of a sub-pixel, theoretically, higher device efficiency and ultrahigh color gamut expression can be obtained. Compared with the traditional si-OLED display panel (WOLED + CF), the display brightness of the product with the design can be improved by more than 20 times. Under the same driving condition of the display panel, the power consumption can be effectively reduced, and the problem of screen burning is solved. Meanwhile, the designed product can solve the problems of display brightness and PPI of the existing micro OLED display panel, has higher brightness and resolution, can overcome or offset the limitation of an optical device, and realizes the original unimaginable target.

Generally, the OLED display panel (with the light emitting layer patterned) theoretically can meet the requirements of high efficiency and high color gamut, such as a Low Temperature Polysilicon (LTPS) OLED display panel used in mass production of mobile phones. However, unlike the OLED display panel of the glass substrate or the flexible substrate, a high PPI (PPI)>3000 Sub-pixels in a si-OLED display panel are near semiconductor scale, approximately 5 x 5 μm in size ² (square micrometers) or even smaller and the distance between the light emitting areas of the sub-pixels is less than 2 μm (micrometers). These characteristics of the si-OLED display panel cause new problems in the fabrication of the si-OLED display panel (the patterning of the light emitting layer), and also present higher requirements and challenges.

For a si-OLED display panel (a light emitting layer is subjected to patterning design), to pattern and prepare a light emitting layer of a sub-pixel with an ultra-small size and an optical adjustment (prime) layer, a mask (mask) with a large aspect ratio is required to be used for preparation (the mask with the large aspect ratio is used for indicating that the ratio of the depth of an opening used for forming a pattern in the mask to the width of the opening is large). The mask with the large depth-to-width ratio has a certain collimation effect on an evaporation pattern during patterned evaporation. Thus, the accuracy requirement of the evaporation pattern formed in the si-OLED display panel can be met, and the sizes of the light-emitting layer of the sub-pixel and the patterned shadow (shadow) of the prime layer are strictly controlled to be less than 1-2 μm. That is, unlike a Fine Metal Mask (FMM) technique for preparing a light emitting layer in a conventional OLED display panel, a mask used for a patterned film layer in a si-OLED display panel is required to have a large aspect ratio. In the preparation of the si-OLED display panel, not only patterning of the emission layer (EML) but also patterning of the prime layer by a mask (high aspect ratio) is required. However, the mask with a large aspect ratio is prone to material accumulation at the part of the opening in the evaporation process, thereby causing distortion of the formed pattern. That is, the mask not only has a short lifetime, but also affects the yield of the sub-pixels.

At present, the OLED device in the OLED display panel has a cavity length (also referred to as a microcavity length) of a gain optical cavity of a second node with higher efficiency, and optical cavity lengths of sub-pixels with different colors under the second node are different, so that the difference in thickness of film layers in the sub-pixels with different colors is larger. For example, referring to FIG. 1, the optical cavity length of the red sub-pixel is greater than the optical cavity length of the green sub-pixel, which is greater than the optical cavity length of the blue sub-pixel. Thus, the thickness of the film in the red sub-pixel is greater than the thickness of the film in the green sub-pixel, and the thickness of the film in the green sub-pixel is greater than the thickness of the film in the blue sub-pixel, e.g., the film in the red sub-pixel is about 50nm (nanometers) thicker than the film in the green sub-pixel, and the film in the blue sub-pixel is about 90nm thicker than the film in the blue sub-pixel.

However, in the si-OLED display panel, since the size of the sub-pixels is small and the distance between the light emitting areas of the sub-pixels is small, a partition edge angle of a Pixel Defining Layer (PDL) for partitioning the light emitting areas of adjacent sub-pixels is large. Furthermore, if the thickness difference of the film layers in the sub-pixels with different colors is large, local virtual connection or fracture of the cathode layer shared by all the sub-pixels in the display panel is easily caused, and the display efficiency and the display effect of the display panel are seriously reduced.

In addition, the film between the light emitting layer and the anode layer of the sub-pixel is more likely to cause electrical crosstalk between the sub-pixels than the film on the side of the light emitting layer away from the anode layer. In fig. 1, because carrier mobility of a Hole Injection Layer (HIL) and a Hole Transport Layer (HTL) between a light emitting layer and an anode layer of a subpixel is relatively high, carriers of the subpixel may be transported to a subpixel adjacent to the subpixel, so that a relatively large lateral current is generated, and electrical crosstalk may be generated between a plurality of subpixels, which affects display effect (e.g., affects color gamut) of the display device.

Fig. 2 is a schematic structural diagram of a display panel according to an embodiment of the present disclosure. As can be seen with reference to fig. 2, the display panel 10 may include: a base substrate 101, a plurality of sub-pixels 102 located on one side of the base substrate 101, and a light extraction layer (CPL) 103 located on one side of the plurality of sub-pixels 102 away from the base substrate 101.

Referring to fig. 2, each sub-pixel 102 may include an anode layer 1021, a functional film layer 1022, and a cathode layer 1023 stacked in sequence. The cathode layer 1023 of the plurality of sub-pixels 102 in the display panel 10 may be a common film layer. The common film layer can be used to indicate that its orthographic projection on the substrate 101 is located in the area where the plurality of sub-pixels 102 are located, and is located in the interval area of the plurality of sub-pixels 102. The common film layer can be a common film layer which is not subjected to patterning treatment by using a mask plate. In fig. 2, the functional film layer is taken as an example of a common film layer, and actually the functional film layer 1022 may include a plurality of film layers, a part of the plurality of film layers may be the common film layer, and another part of the plurality of film layers is not the common film layer.

The plurality of sub-pixels 102 includes at least a sub-pixel 102a of a first color and a sub-pixel 102b of a second color. The light extraction layer 103 includes at least a first portion 1031 and a second portion 1032, an orthogonal projection of the first portion 1031 on the substrate base 101 at least partially overlaps an orthogonal projection of the sub-pixel 102a of the first color on the substrate base 101 (the first portion 1031 corresponds to the sub-pixel 102a of the first color), and an orthogonal projection of the second portion 1032 on the substrate base 101 at least partially overlaps an orthogonal projection of the sub-pixel 102b of the second color on the substrate base 101 (the second portion 1032 corresponds to the sub-pixel 102b of the second color). That is, light emitted from the sub-pixel 102a of the first color may be emitted from the first portion 1031 of the light extraction layer 103, and light emitted from the sub-pixel 102b of the second color may be emitted from the second portion 1032 of the light extraction layer 103.

In the embodiment of the present application, a difference between distances between the surface of the functional film layer 1022 far away from the substrate 101 and the substrate 101 of any two sub-pixels 102 in the plurality of sub-pixels 102 is smaller than a difference threshold. The difference threshold may be as small as possible, provided that uniformity of the lifetimes of the different colored sub-pixels 102 is ensured. For example, the difference threshold may be 10nm (nanometers).

Optionally, the difference between the distance between the surface of the functional film layer 1022 in the sub-pixel 102a of the first color far away from the base substrate 101 and the base substrate 101, and the distance between the surface of the functional film layer 1022 in the sub-pixel 102b of the second color far away from the base substrate 101 and the base substrate 101 is smaller than the difference threshold. That is, the distance between the surface of the functional film layer 1022 far away from the substrate 101 in the sub-pixel 102a of the first color and the substrate 101 may be smaller than the distance between the surface of the functional film layer 1022 far away from the substrate 101 and the substrate 101 in the sub-pixel 102b of the second color, i.e., the two may be approximately equal. Thus, the surface of the sub-pixel 102a of the first color for forming the cathode layer 1023 and the surface of the sub-pixel 102b of the second color for forming the cathode layer 1023 can be approximately coplanar. Further, the flatness of the surface on which the cathode layer 1023 is formed can be improved, the probability of breakage of the cathode layer 1023 can be reduced, and the display effect of the display panel 10 can be ensured.

Meanwhile, the thickness of the first portion 1031 of the light extraction layer 103 and the thickness of the second portion 1032 of the light extraction layer 103 are different, that is, the microcavity length of the sub-pixel 102a of the first color and the microcavity length of the sub-pixel 102b of the second color can be made different. Further, the thickness of the first portion 1031 may be made to satisfy the optical gain characteristic of the sub-pixel 102a of the first color, and the thickness of the second portion 1032 may be made to satisfy the optical gain characteristic of the sub-pixel 102b of the second color, while ensuring the light emission efficiency of the sub-pixel 102a of the first color and the sub-pixel 102b of the second color in the display panel 10.

The region where each sub-pixel 102 is located forms a micro-cavity of the sub-pixel 102, and each sub-pixel 102 can efficiently emit light under the action of the micro-cavity. For each subpixel 102, the microcavity length of the subpixel 102 can be used to represent the distance between the surface of the anode layer 1021 in the subpixel 102 away from the substrate 101 and the surface of the subpixel 102 from which light is emitted. In the embodiment of the present application, the light emitted by the sub-pixel 102 can be emitted from the surface of the light extraction layer 103 away from the substrate 101, and therefore the surface of the light extraction layer 103 away from the substrate 101 can be the surface of the sub-pixel 102 emitting light. Thus, the microcavity length of the first color sub-pixel 102a can be used to represent the distance between the surface of the anode layer 1021 of the first color sub-pixel 102a away from the substrate 101 and the surface of the first portion 1031 of the light extraction layer 103 away from the substrate 101. The microcavity length of the sub-pixel 102b of the second color can be used to represent the distance between the surface of the anode layer 1021 of the sub-pixel 102b of the second color away from the base substrate 101 and the second portion 1032 of the light extraction layer 103 and the surface away from the base substrate 101.

That is, the display panel 10 provided in the embodiment of the present application can reduce the probability of fracture of the cathode layer 1023 on the premise of meeting the optical gain characteristics of the sub-pixels 102 of different colors, and ensure the light emitting efficiency of the sub-pixels 102 in the display panel 10 and the display effect of the display panel 10.

In summary, the embodiment of the present application provides a display panel, which includes a plurality of sub-pixels and a light extraction layer, where each sub-pixel includes an anode layer, a functional film layer, and a cathode layer that are sequentially stacked. The plurality of sub-pixels includes at least a sub-pixel of a first color and a sub-pixel of a second color. Because the difference value of the distances between the surface of the functional film layer far away from the substrate base plate and the substrate base plate in any two sub-pixels is smaller than the difference threshold value, the flatness of the surface of the cathode layer formed in the region where the sub-pixels with different colors are located is better, the probability of breakage of the cathode layer is reduced, and the display effect of the display panel is improved. Meanwhile, the thickness of the first part corresponding to the sub-pixel of the first color in the light extraction layer is different from the thickness of the second part corresponding to the sub-pixel of the second color, so that the thickness of the light extraction layer can meet the optical gain characteristic of the corresponding sub-pixel, and the luminous efficiency of the sub-pixel in the display panel is ensured.

Alternatively, the display panel 10 may be a silicon-based display panel. The display panel 10 may be applied to an AR device or a VR device.

Alternatively, the microcavity length for the first color sub-pixel 102a can be greater than the microcavity length for the second color sub-pixel 102b. That is, the distance between the surface of the anode layer 1021 in the sub-pixel 102a of the first color near the substrate base 101 and the surface of the first portion 1031 of the light extraction layer 103 far from the substrate base 101 is greater than the distance between the surface of the anode layer 1021 in the sub-pixel 102b of the second color near the substrate base 101 and the surface of the second portion 1032 of the light extraction layer 103 far from the substrate base 101. Accordingly, the thickness of the first portion 1031 of the light extraction layer 103 corresponding to the sub-pixel 102a of the first color may be greater than the thickness of the second portion 1032 of the light extraction layer 103 corresponding to the sub-pixel 102b of the second color.

Referring to fig. 3, the plurality of subpixels 102 may further include a subpixel 102c of a third color. The light extraction layer 103 may also include a third portion 1033. The orthographic projection of the third portion 1033 on the substrate base plate 101 at least partially overlaps the orthographic projection of the sub-pixel 102c of the third color on the substrate base plate 101 (the third portion 1033 corresponds to the sub-pixel 102c of the third color). That is, light emitted from the sub-pixel 102c of the third color may be emitted from the third portion 1033 of the light extraction layer 103.

Since the difference between the distances between the surface of the functional film layer 1022 of any two sub-pixels 102 in the plurality of sub-pixels 102 away from the base substrate 101 and the base substrate 101 is smaller than the difference threshold, the distance between the surface of the functional film layer 1022 of the sub-pixel 102c of the third color away from the base substrate 101 and the base substrate 101 may be smaller than the difference threshold, both the distance between the surface of the functional film layer 1022 of the sub-pixel 102a of the first color away from the base substrate 101 and the distance between the surface of the functional film layer 1022 of the sub-pixel 102b of the second color away from the base substrate 101 and the base substrate 101. That is, the surface of the sub-pixel 102a of the first color for forming the cathode layer 1023, the surface of the sub-pixel 102b of the second color for forming the cathode layer 1023, and the surface of the sub-pixel 102c of the third color for forming the cathode layer 1023 are approximately coplanar. This improves the flatness of the surface of the cathode layer 1023 (common film layer) to be formed, reduces the probability of breakage of the cathode layer 1023, and ensures the display effect of the display panel 10.

Meanwhile, the thickness of the third portion 1033 of the light extraction layer 103 may be different from the thickness of the first portion 1031 of the light extraction layer 103 and different from the thickness of the second portion 1032 of the light extraction layer 103. Thus, the microcavity length of the sub-pixel 102c of the third color can be made different from both the microcavity length of the sub-pixel 102a of the first color and the microcavity length of the sub-pixel 102b of the second color. Further, the thickness of the third portion 1033 may be made to satisfy the optical gain characteristic of the sub-pixel 102c of the third color, so as to ensure the luminous efficiency of the sub-pixel 102c of the third color in the display panel 10.

Alternatively, the microcavity length for the second color sub-pixel 102b can be greater than the microcavity length for the third color sub-pixel 102c. That is, the distance between the surface of the anode layer 1021 in the sub-pixel 102b of the second color close to the substrate 101 and the surface of the second portion 1032 of the light extraction layer 103 away from the substrate 101 is larger than the distance between the surface of the anode layer 1021 in the sub-pixel 102c of the third color close to the substrate 101 and the surface of the third portion 1033 of the light extraction layer 103 away from the substrate 101. Accordingly, the thickness of the second portion 1032 of the light extraction layer 103 corresponding to the sub-pixel 102b of the second color may be greater than the thickness of the third portion 1033 of the light extraction layer 103 corresponding to the sub-pixel 102c of the third color.

In the embodiment of the present application, the plurality of sub-pixels 102 of the display panel 10 may include a red (R) sub-pixel, a green (G) sub-pixel, and a blue (B) sub-pixel. In order to satisfy the optical gain characteristics of the sub-pixels 102 of different colors, the microcavity length of the red sub-pixel 102 is longer than that of the green sub-pixel 102, and the microcavity length of the green sub-pixel is longer than that of the blue sub-pixel. Thus, in the embodiment of the present application, the first color is red (the sub-pixel 102a of the first color is a red sub-pixel), the second color is green (the sub-pixel 102b of the second color is a green sub-pixel), and the third color is blue (the sub-pixel 102c of the third color is a blue sub-pixel).

Referring to fig. 3, the functional film layer 1022 may include: an Electron Injection Layer (EIL) 10221a, an Electron Transport Layer (ETL) 10222a, a light emitting layer 10223a, an optical adjustment layer 10224a, a hole transport layer 10225a, and a hole injection layer 10226a, which are sequentially stacked in a direction away from the substrate 101.

Referring to fig. 3, the light emitting layer 10223a and the optical adjustment layer 10224a in the functional film layers 1022 of the plurality of sub-pixels 102 are both patterned film layers. The electron injection layer 10221a, the electron transport layer 10222a, the hole transport layer 10225a and the hole injection layer 10226a in the functional film layers 1022 of the plurality of sub-pixels 102 are all common film layers.

The patterned film layer includes a plurality of patterns arranged at intervals, and orthographic projections of the plurality of patterns on the substrate 101 are located in regions where the plurality of sub-pixels 102 are located, and are not located in the interval regions of the plurality of sub-pixels 102. For example, the patterned film layer may include the same number of patterns as the number of sub-pixels 102, and each pattern is located in a region where one sub-pixel 102 is located. The patterned film layer may be a non-common film layer patterned by a mask.

The material of the light emitting layer 10223a of the first color sub-pixel 102a may be a red light emitting material (the light emitting layer 10223a of the first color sub-pixel 102a may be a red light emitting material layer), the material of the light emitting layer 10223a of the second color sub-pixel 102b may be a green light emitting material (the light emitting layer 10223a of the second color sub-pixel 102b may be a green light emitting material layer), and the material of the light emitting layer 10223a of the third color sub-pixel 102c may be a blue light emitting material (the light emitting layer 10223a of the third color sub-pixel 102c may be a blue light emitting material layer). This makes the display panel 10 emit light of a plurality of colors, and the color gamut of the display panel 10 is high.

In general, the carrier mobility of the electron injection layer 10221a and the electron transport layer 10222a is smaller than that of the hole injection layer 10226a and the hole transport layer 10225a, so compared with the related art, in the display panel 10 of the embodiment of the present application, the electron injection layer 10221a and the electron transport layer 10222a are designed close to the anode layer 1021 relative to the hole injection layer 10226a and the hole transport layer 10225a, and the light emitting layer 10223a is designed close to the anode layer 1021 relative to the optical adjustment layer 10224a, which can reduce the lateral leakage between the sub-pixels 102, effectively reduce the probability of the electrical crosstalk between the sub-pixels 102, and greatly improve the color gamut of the display panel and the contrast of the display panel.

In the display panel 10 shown in fig. 3, the light emitting layer 10223a and the optical adjustment layer 10224a in the functional film layer 1022 of the sub-pixel 102 are patterned. Wherein the thicknesses of the light emitting layers 10223a of the sub-pixels 102 of different colors can be kept uniform, for example, 30nm (nanometers) each, or the thicknesses of the light emitting layers 10223a of the sub-pixels 102 of different colors can allow a certain thickness difference (difference less than 10 nm) according to the lifetime requirement of the sub-pixels 102 of different colors. The optical adjustment layer 10224a of the sub-pixel 102 of different colors only needs to satisfy the function of electrically blocking carriers without requiring its function of participating in optical adjustment, and thus the optical adjustment layer 10224a may have a thickness ranging from 5nm to 10nm. Thus, the thickness of the film layer to be patterned in the display panel 10 shown in fig. 3 can be uniformly 35nm ± 10nm. That is, the difference in the film thickness of the entire display panel 10 can be made as small as possible, so that the flatness of the surface on which the cathode layer 1023 is formed is good, and the probability of fracture of the cathode layer 1023 is reduced, which has a crucial influence on the high PPI display technology.

Fig. 4 is a schematic structural diagram of another display panel provided in the embodiment of the present application. Referring to fig. 4, it can be seen that the electron injection layer 10221a and the electron transport layer 10222a of the plurality of sub-pixels 102 may be patterned film layers. Therefore, the display panel 10 shown in fig. 4 is capable of blocking the lateral transmission of carriers and avoiding the lateral electrical crosstalk between the sub-pixels 102, compared with the display panel 10 shown in fig. 3.

In the display panel 10 shown in fig. 4, the electron injection layer 10221a, the electron transport layer 10222a, the light emitting layer 10223a, and the optical adjustment layer 10224a in the functional film layer 1022 of the sub-pixel 102 are patterned. Wherein the total thickness of the electron injection layer 10221a and the electron transport layer 10222a of the sub-pixels 102 of different colors can be kept uniform, for example, less than 35nm. The total thickness of the electron injection layer 10221a and the electron transport layer 10222a can be adjusted based on the film material thereof and the thickness of the anode layer 1021. The thicknesses of the light emitting layers 10223a of the sub-pixels 102 of different colors can be kept uniform, for example, 30nm, or the thicknesses of the light emitting layers 10223a of the sub-pixels 102 of different colors can allow a certain thickness difference (difference less than 10 nm) according to the lifetime requirement of the sub-pixels 102 of different colors. The optical adjustment layer 10224a of the sub-pixel 102 of different colors only needs to satisfy the function of electrically blocking carriers without requiring its function of participating in optical adjustment, and thus the optical adjustment layer 10224a may have a thickness ranging from 5nm to 10nm. Thus, the thickness of the film layer to be patterned in the display panel 10 shown in fig. 4 may be uniform to 70nm ± 10nm.

That is, the display panel 10 shown in fig. 4 can completely block the lateral transfer of carriers compared to the display panel 10 shown in fig. 3, but the difference in the film thickness of the entire display panel 10 is large. In the embodiment of the present application, when designing the electron injection layer 10221a and the electron transport layer 10222a of the display panel 10, the design can be specifically made by comprehensively considering the lateral leakage and the difference of the film thickness.

In the display panel 10 shown in fig. 3 and 4, the sub-pixel 102a of the first color may include: an anode layer 1021, an Electron Injection Layer (EIL) 10221a, an Electron Transport Layer (ETL) 10222a, a red light emitting material layer (R-EML) 10223a, a red optical adjustment layer (R-prime) 10224a, a Hole Transport Layer (HTL) 10225a, a Hole Injection Layer (HIL) 10226a, a cathode layer 1023, and a first portion 1031 of a light extraction layer 103 are sequentially stacked. The sub-pixel 102b of the second color may include: an anode layer 1021, an Electron Injection Layer (EIL) 10221a, an Electron Transport Layer (ETL) 10222a, a green light emitting material layer (G-EML) 10223a, a green optical adjustment layer (G-prime) 10224a, a Hole Transport Layer (HTL) 10225a, a Hole Injection Layer (HIL) 10226a, a cathode layer 1023, and a second portion 1032 of the light extraction layer 103 are sequentially stacked. The sub-pixel 102c of the third color may include: an anode layer 1021, an Electron Injection Layer (EIL) 10221a, an Electron Transport Layer (ETL) 10222a, a blue light emitting material layer (B-EML) 10223a, a red optical adjustment layer (B-prime) 10224a, a Hole Transport Layer (HTL) 10225a, a Hole Injection Layer (HIL) 10226a, a cathode layer 1023, and a third portion 1033 of the light extraction layer 103 are sequentially stacked.

Fig. 5 is a schematic structural diagram of another display panel provided in the embodiment of the present application. As can be seen with reference to fig. 5, the functional film layer 1022 may include: a first electron injection layer 10221b, a first electron transport layer 10222b, a first light emitting layer 10223b, a first optical adjustment layer 10224b, a first hole transport layer 10225b, a Charge Generation Layer (CGL) 10226b, a second electron injection layer 10227b, a second electron transport layer 10228b, a second light emitting layer 10229b, a second optical adjustment layer 102210b, a second hole transport layer 102211b, and a hole injection layer 102212b, which are sequentially stacked in a direction away from the substrate 101. That is, the sub-pixels 102 in the display panel 10 shown in fig. 5 may have a stacked structure.

Referring to fig. 5, the first electron injection layer 10221b, the first electron transport layer 10222b, the first light emitting layer 10223b, the first optical adjustment layer 10224b, the charge generation layer 10226b, the second light emitting layer 10229b and the second optical adjustment layer 102210b in the functional film 1022 of the plurality of sub-pixels 102 are all patterned films. The first hole transport layer 10225b, the second electron injection layer 10227b, the second electron transport layer 10228b, the second hole transport layer 102211b and the hole injection layer 102212b in the functional film layers 1022 of the plurality of sub-pixels 102 are all common film layers.

Of course, in order to completely block the lateral transfer of carriers, the first electron injection layer 10221b and the first electron transfer layer 10222b may be made as patterned film layers. The embodiment of the present application does not limit this.

In the display panel shown in fig. 5, the sub-pixel 102a of the first color may include: an anode layer 1021, a first Electron Injection Layer (EIL) 10221b, a first Electron Transport Layer (ETL) 10222b, a red light emitting material layer (R-EML) 10223b, a red optical adjustment layer (R-prime) 10224b, a first Hole Transport Layer (HTL) 10225b, a Charge Generation Layer (CGL) 10226b, a second Electron Injection Layer (EIL) 10227b, a second Electron Transport Layer (ETL) 5754 zft 5754 b, a red light emitting material layer (R-EML) 10229b, a red optical adjustment layer (R-prime) 102210b, a second Hole Transport Layer (HTL) 102211b, a hole injection layer 102212b, a cathode layer 1023, and a first portion 1031 of a light extraction layer 103 are sequentially stacked. The sub-pixel 102b of the second color may include: an anode layer 1021, a first Electron Injection Layer (EIL) 10221b, a first Electron Transport Layer (ETL) 10222b, a green light emitting material layer (G-EML) 10223b, a green optical adjustment layer (G-prime) 10224b, a first Hole Transport Layer (HTL) 10225b, a Charge Generation Layer (CGL) 10226b, a second Electron Injection Layer (EIL) 10227b, a second Electron Transport Layer (ETL) 5754 zft 5754 b, a green light emitting material layer (R-EML) 10229b, a green optical adjustment layer (R-prime) 102210b, a second Hole Transport Layer (HTL) 102211b, a hole injection layer 102212b, a cathode layer 1023, and a second portion 1032 of the light extraction layer 103 are sequentially stacked. The sub-pixel 102c of the third color may include: an anode layer 1021, a first Electron Injection Layer (EIL) 10221B, a first Electron Transport Layer (ETL) 10222B, a blue light emitting material layer (B-EML) 10223B, a blue optical adjustment layer (B-prime) 10224a, a first Hole Transport Layer (HTL) 10225B, a Charge Generation Layer (CGL) 10226B, a second Electron Injection Layer (EIL) 10227B, a second Electron Transport Layer (ETL) 5754 zft 5754B, a blue light emitting material layer (B-EML) 10229B, a blue optical adjustment layer (B-prime) 102210B, a second Hole Transport Layer (HTL) 3532B, a hole injection layer 102212B, a cathode layer 1023, and a third portion 1033 of the light extraction layer 103 are sequentially stacked.

Fig. 6 is a schematic structural diagram of another display panel according to an embodiment of the present disclosure. Referring to fig. 6, the functional film layer 1022 may include: a hole injection layer 10221c, a hole transport layer 10222c, a first light emitting layer 10223c, a second light emitting layer 10224c, a first Hole Block Layer (HBL) 10225c, a charge generation layer 10226c, a third light emitting layer 10227c, a second hole block layer 10228c, an electron transport layer 10229c, and an electron injection layer 102210c, which are sequentially stacked in a direction away from the substrate 101.

Referring to fig. 6, the hole injection layer 10221c, the hole transport layer 10222c and the charge generation layer 10226c in the functional film layer 1022 of the plurality of sub-pixels 102 are all patterned film layers. The first light-emitting layer 10223c, the second light-emitting layer 10224c, the first hole blocking layer 10225c, the third light-emitting layer 10227c, the second hole blocking layer 10228c, the electron transport layer 10229c, and the electron injection layer 102210c in the functional film layers 1022 of the plurality of subpixels 102 are all common film layers.

Since the hole injection layer 10221c, the hole transport layer 10222c and the charge generation layer 10226c are all patterned film layers, lateral transport of carriers can be completely blocked.

Alternatively, in the display panel 10 shown in fig. 6, the hole injection layer 10221c may be exchanged with the electron injection layer 102210c, and the hole transport layer 10222c may be exchanged with the electron transport layer 10229 c. In this case, since the electron injection layer 102210c and the electron transport layer 10229c have low carrier mobilities with respect to the hole injection layer 10221c and the hole transport layer 10222c, the electron injection layer 102210c and the electron transport layer 10229c may be made to be a common film layer in order to reduce the difference in film thickness of the entire display panel 10 as much as possible. Of course, the electron injection layer 102210c and the electron transport layer 10229c may be patterned film layers to completely block the lateral transport of carriers. The embodiment of the present application does not limit this.

In the embodiment of the present application, the light emitted from the first light emitting layer 10223c, the light emitted from the second light emitting layer 10224c, and the light emitted from the third light emitting layer 10227c may be mixed to form white light. For example, the first light emitting layer 10223c may be made of a red phosphor material, and the color of light emitted from the first light emitting layer 10223c may be red. The second light emitting layer 10224c may be made of a green phosphorescent material, and the color of light emitted from the second light emitting layer 10224c may be green. The third light emitting layer 10227c may be made of a blue fluorescent material, and the color of light emitted from the third light emitting layer 10227c may be blue.

The light emitted from the sub-pixel 102 in the display panel 10 shown in fig. 6 after passing through the cathode layer 1023 is white light. The light extraction layer 103 having different thicknesses may transmit light of different colors, for example, the light transmitted through the first portion 1031 may be red, the light transmitted through the second portion 1032 may be green, and the light transmitted through the third portion 1033 may be blue.

As can be seen with reference to fig. 6, the display panel 10 may further include: a color film layer 104. The color film layer 104 may be located on a side of the plurality of sub-pixels 102 away from the substrate base 101. The color film layer 104 may include a plurality of color-resisting blocks 1041 of different colors, and an area where each sub-pixel 102 is located in an orthogonal projection of one color-resisting block 1041 on the substrate base plate 101.

For example, three sub-pixels 102 and three color-blocking blocks 1041 are shown in fig. 6, the color of the color-blocking block 1041 corresponding to the sub-pixel 102a of the first color may be red, the color of the color-blocking block 1041 corresponding to the sub-pixel 102b of the second color may be green, and the color of the color-blocking block 1041 corresponding to the sub-pixel 102c of the third color may be blue.

By arranging the color film layer 104 on the side of the sub-pixel 102 away from the substrate base plate 101, light passing through the light extraction layer 103 can pass through the color blocking blocks 1041 of different colors in the color film layer 104, and the display effect of the display panel 10 is improved.

In the display panel 10 shown in fig. 6, the sub-pixel 102a of the first color may include: an anode layer 1021, a Hole Injection Layer (HIL) 10221c, a Hole Transport Layer (HTL) 10222c, a red light emitting material layer (R-EML) 10223c, a green light emitting material layer (G-EML) 10224c, a first Hole Blocking Layer (HBL) 10225c, a Charge Generation Layer (CGL) 10226c, a blue light emitting material layer (B-EML) 10227c, a second Hole Blocking Layer (HBL) 10228c, an Electron Transport Layer (ETL) 10229c, an Electron Injection Layer (EIL) 102210c, a cathode layer 1023, and a first portion 1031 of the light extraction layer 103, which are sequentially stacked. The sub-pixel 102b of the second color may include: an anode layer 1021, a Hole Injection Layer (HIL) 10221c, a Hole Transport Layer (HTL) 10222c, a red light emitting material layer (R-EML) 10223c, a green light emitting material layer (G-EML) 10224c, a first Hole Blocking Layer (HBL) 10225c, a Charge Generation Layer (CGL) 10226c, a blue light emitting material layer (B-EML) 10227c, a second Hole Blocking Layer (HBL) 10228c, an Electron Transport Layer (ETL) 10229c, an Electron Injection Layer (EIL) 102210c, a cathode layer 1023, and a second portion 1032 of the light extraction layer 103 are sequentially stacked. The sub-pixel 102c of the third color may include: an anode layer 1021, a Hole Injection Layer (HIL) 10221c, a Hole Transport Layer (HTL) 10222c, a red light emitting material layer (R-EML) 10223c, a green light emitting material layer (G-EML) 10224c, a first Hole Blocking Layer (HBL) 10225c, a Charge Generation Layer (CGL) 10226c, a blue light emitting material layer (B-EML) 10227c, a second Hole Blocking Layer (HBL) 10228c, an Electron Transport Layer (ETL) 10229c, an Electron Injection Layer (EIL) 102210c, a cathode layer 1023, and a third portion 1033 of the light extraction layer 103, which are sequentially stacked.

In the embodiment, the anode layer 1021 of the sub-pixel 102 may be made of Indium Tin Oxide (ITO). The cathode layer 1023 of the sub-pixel 102 may be made of a high-transmittance metal material, such as magnesium-silver (Mg-Ag) or indium-zinc-oxide (IZO). The indium zinc oxide has good wrapping property and continuity, and can further avoid fracture of the cathode layer 1023 and ensure the yield of the display panel.

As can be seen by referring to fig. 3 to 6, the display panel 10 may further include a thin-film encapsulation (TFE) layer 105. The encapsulation film layer 105 may be located on a side of the light extraction layer 103 away from the substrate base plate 101. The encapsulation film layer 105 may include: the first film layer, the second film layer and the third film layer are stacked along a direction far away from the substrate base plate 101.

Alternatively, the first film layer and the third film layer may be made of an inorganic material, and the second film layer may be made of an organic material. For example, the first and third layers may be made of one or more inorganic oxides such as SiNx, siOx, and SiOxNy. The second film layer may be made of a resin material. The resin may be a thermoplastic resin or a thermoplastic resin, the thermoplastic resin may include a acryl (PMMA) resin, and the thermosetting resin may include an epoxy resin.

In the embodiment of the present application, the second film layer may be manufactured by Ink Jet Printing (IJP). The first film layer and the third film layer can be formed by Chemical Vapor Deposition (CVD).

Where the display panel includes an encapsulation film layer 105, the gain optical cavity of the subpixel 102 may be formed by the anode layer 1021 of the subpixel 102 and a film layer between the first film layer in the encapsulation film layer 105. Thus, the thickness of the film between the anode layer 1021 of the subpixel 102 and the first film in the encapsulation film 105 affects the microcavity length of the subpixel 102. Optionally, in the embodiment of the present application, the thicknesses of the light extraction layers 103 corresponding to the sub-pixels 102 with different colors may be adjusted, so that the lengths of the micro-cavities of the sub-pixels 102 with different colors are different, and the optical gain characteristics of the sub-pixels 102 with different colors are satisfied.

Referring to fig. 3 to 6, the display panel 10 may further include: a pixel defining layer 106, the pixel defining layer 106 may be located on a side of the anode layer 1021 remote from the substrate 101. The pixel defining layer 106 may have a plurality of hollow areas, and each hollow area may be used to expose the anode layer of one sub-pixel. Also, the pixel defining layer may cover an edge of the anode layer of each sub-pixel.

In summary, the present application provides a display panel, which includes a plurality of sub-pixels and a light extraction layer, where each sub-pixel includes an anode layer, a functional film layer, and a cathode layer, which are sequentially stacked. The plurality of sub-pixels includes at least a sub-pixel of a first color and a sub-pixel of a second color. Because the difference value of the distances between the surface of the functional film layer far away from the substrate base plate and the substrate base plate in any two sub-pixels is smaller than the difference threshold value, the flatness of the surface of the cathode layer formed in the region where the sub-pixels with different colors are located is better, the probability of breakage of the cathode layer is reduced, and the display effect of the display panel is improved. Meanwhile, the thickness of the first part corresponding to the sub-pixel of the first color in the light extraction layer is different from the thickness of the second part corresponding to the sub-pixel of the second color, so that the thickness of the light extraction layer can meet the optical gain characteristic of the corresponding sub-pixel, and the luminous efficiency of the sub-pixel in the display panel is ensured.

Fig. 7 is a schematic structural diagram of a display device according to an embodiment of the present application. Referring to fig. 7, the display device may include: the power supply assembly 20 and the display panel 10 provided in the above embodiments. The power supply assembly 20 may be used to supply power to the display panel 10.

Optionally, the display device may be any product or component having a display function and a fingerprint identification function, such as a si-OLED display device, electronic paper, a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, or a navigator.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed above could be termed a second element, component, region, layer or section without departing from the teachings of the present disclosure.

Spatially relative terms such as "below …", "above …", "left", "right", and the like may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that these spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below …" may encompass both orientations above … and below …. The devices may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. In addition, it will also be understood that when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. The particular features, structures, materials, or characteristics described in this specification may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and/or the present specification and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The above description is only exemplary of the present application and should not be taken as limiting, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A display panel, characterized in that the display panel (10) comprises:

a substrate base plate (101);

a plurality of sub-pixels (102) located on one side of the substrate (101), each sub-pixel (102) comprising an anode layer (1021), a functional film layer (1022) and a cathode layer (1023) which are sequentially stacked, wherein a micro-cavity of the sub-pixel (102) is formed in the area where each sub-pixel (102) is located, and the plurality of sub-pixels (102) at least comprise a sub-pixel (102 a) of a first color and a sub-pixel (102 b) of a second color;

and a light extraction layer (103) located on a side of the plurality of sub-pixels (102) remote from the substrate base plate (101), the light extraction layer (103) comprising at least a first portion (1031) and a second portion (1032), an orthographic projection of the first portion (1031) on the substrate base plate (101) at least partially overlapping an orthographic projection of the sub-pixel (102 a) of the first color on the substrate base plate (101), an orthographic projection of the second portion (1032) on the substrate base plate (101) at least partially overlapping an orthographic projection of the sub-pixel (102 b) of the second color on the substrate base plate (101);

wherein a difference in distance between a surface of the functional film layer (1022) of any two of the sub-pixels (102) away from the substrate base plate (101) and the substrate base plate (101) is smaller than a difference threshold, and a thickness of the first portion (1031) and a thickness of the second portion (1032) are different.

2. A display panel according to claim 1, wherein the microcavity length of the sub-pixel (102 a) of the first color is larger than the microcavity length of the sub-pixel (102 b) of the second color, and the thickness of the first portion (1031) is larger than the thickness of the second portion (1032);

wherein, for each sub-pixel (102), the microcavity length of the sub-pixel (102) is used to represent the distance between the surface of the anode layer (1021) in the sub-pixel (102) far away from the substrate (101) and the surface of the sub-pixel (102) emitting light.

3. The display panel according to claim 2, wherein the plurality of sub-pixels (102) further comprises sub-pixels (102 c) of a third color, the light extraction layer (103) further comprises a third portion (1033), an orthographic projection of the third portion (1033) on the substrate (101) at least partially overlaps with an orthographic projection of the sub-pixels (102 c) of the third color on the substrate (101);

the third portion (1033) has a thickness different from a thickness of the first portion (1031) and different from a thickness of the second portion (1032).

4. A display panel according to claim 3, wherein the microcavity length for the sub-pixel (102 b) of the second color is greater than the microcavity length for the sub-pixel (102 c) of the third color, and the thickness of the second portion (1032) is greater than the thickness of the third portion (1033).

5. The display panel according to claim 4, wherein the first color is red, the second color is green, and the third color is blue.

6. The display panel according to any one of claims 1 to 5, wherein the functional film layer (1022) comprises: the light-emitting diode comprises an electron injection layer, an electron transport layer, a light-emitting layer, an optical adjustment layer, a hole transport layer and a hole injection layer which are sequentially stacked in the direction away from the substrate (101).

7. The display panel according to claim 6, wherein the light emitting layer and the optical adjustment layer in the functional film layer (1022) of the plurality of sub-pixels (102) are both patterned film layers;

the hole transport layer and the hole injection layer in the functional film layers (1022) of the plurality of sub-pixels (102) are both common film layers;

the electron injection layer and the electron transport layer in the functional film layers (1022) of the plurality of sub-pixels (102) are both patterned film layers, or the electron injection layer and the electron transport layer in the functional film layers (1022) of the plurality of sub-pixels (102) are both common film layers;

the patterned film layer comprises a plurality of patterns arranged at intervals, orthographic projections of the patterns on the substrate base plate (101) are located in the areas where the sub-pixels (102) are located and are not located in the interval areas of the sub-pixels (102), and orthographic projections of the shared film layer on the substrate base plate (101) are located in the areas where the sub-pixels (102) are located and are located in the interval areas of the sub-pixels (102).

8. The display panel according to any one of claims 1 to 5, wherein the functional film layer (1022) comprises: the light-emitting diode comprises a first electron injection layer, a first electron transport layer, a first light-emitting layer, a first optical adjustment layer, a first hole transport layer, a charge generation layer, a second electron injection layer, a second electron transport layer, a second light-emitting layer, a second optical adjustment layer, a second hole transport layer and a hole injection layer which are sequentially stacked along the direction far away from the substrate base plate (101).

9. The display panel of claim 8, wherein the first light emitting layer, the first optical adjustment layer, the charge generation layer, the second light emitting layer and the second optical adjustment layer of the functional film layers (1022) of the plurality of sub-pixels (102) are all patterned film layers;

the first hole transport layer, the second electron injection layer, the second electron transport layer, the second hole transport layer and the hole injection layer in the functional film layers (1022) of the plurality of sub-pixels (102) are all common film layers;

the first electron injection layer and the first electron transport layer in the functional film layers (1022) of the plurality of sub-pixels (102) are both patterned film layers, or the first electron injection layer and the first electron transport layer in the functional film layers (1022) of the plurality of sub-pixels (102) are both common film layers;

10. The display panel according to any one of claims 1 to 5, wherein the functional film layer (1022) comprises: the light-emitting diode comprises a hole injection layer, a hole transport layer, a first light-emitting layer, a second light-emitting layer, a first hole blocking layer, an electric charge generation layer, a third light-emitting layer, a second hole blocking layer, an electron transport layer and an electron injection layer which are sequentially stacked along the direction far away from the substrate base plate (101).

11. The display panel of claim 10, wherein the hole injection layer, the hole transport layer and the charge generation layer of the functional film layers (1022) of the plurality of sub-pixels (102) are patterned film layers;

the first light-emitting layer, the second light-emitting layer, the first hole blocking layer, the third light-emitting layer, the second hole blocking layer, the electron transport layer and the electron injection layer in the functional film layers (1022) of the plurality of sub-pixels (102) are all common film layers;

12. The display panel according to claim 11, wherein the display panel (10) further comprises: a color film layer (104), wherein the color film layer (104) is positioned on one side of the plurality of sub-pixels (102) far away from the substrate base plate (101);

the color film layer (104) comprises a plurality of color blocking blocks (1041) with different colors, and the area of each sub-pixel (102) is positioned in the orthographic projection of one color blocking block (1041) on the substrate (101).

13. The display panel according to any one of claims 1 to 5, wherein the cathode layer (1023) is made of indium zinc oxide.

14. A display panel as claimed in any one of claims 1 to 5, characterized in that the display panel (10) is a silicon-based display panel.

15. A display device, characterized in that the display device comprises: -a power supply assembly (20) and a display panel (10) according to any of claims 1 to 14;

the power supply assembly (20) is used for supplying power to the display panel (10).