Display panel, manufacturing method thereof, and display device

Abstract

The present application discloses a display panel, a manufacturing method thereof, and a display device, belonging to the field of display technologies. The display panel includes: a substrate, on which a plurality of pixel structures are disposed, and a color filter layer is disposed on a side of the plurality of pixel structures away from the substrate. The color filter layer includes a plurality of color filter blocks corresponding to the plurality of pixel structures one by one; each of the plurality of pixel structures emits light of one color, and the color of the light emitted by each pixel structure is the same as the color of the corresponding color filter block. The present application solves the problem of poor display effect of the display panel and improves the display effect of the display panel. The present application is used for display panels.

Description

[0001] This application is a divisional application of the invention patent application with the application date of May 9, 2018, the application number of 201810438219.8, and the invention title of "display panel and its manufacturing method, display device". Technical Field

[0002] This application relates to the field of display technologies, and particularly to a display panel and its manufacturing method, and a display device. Background Art

[0003] With the development of display technologies, organic light-emitting diode (OLED) display panels have been widely used.

[0004] An OLED display panel generally includes a substrate, on which a plurality of OLEDs are provided, and a color filter layer is further provided on a side of the plurality of OLEDs away from the substrate. Exemplarily, the plurality of OLEDs can all emit white light, and the color filter layer includes a plurality of color filter blocks provided in one-to-one correspondence with the plurality of OLEDs, and the plurality of color filter blocks include: a red color filter block, a green color filter block, and a blue color filter block. Each color filter block only allows light of a specified wavelength in the incident white light to pass through. For example, the red color filter block only allows red light to pass through, the green color filter block only allows green light to pass through, and the blue color filter block only allows blue light to pass through, so that the OLED display panel emits colored light.

[0005] However, in related technologies, the color purity of the colored light emitted by the OLED display panel is relatively low, and the display effect of the OLED display panel is poor. Summary of the Invention

[0006] This application provides a display panel and its manufacturing method, and a display device, which can solve the problem of poor display effect of the display panel. The technical solutions are as follows:

[0007] On the one hand, a display panel is provided, and the display panel includes: a substrate,

[0008] a plurality of pixel structures are provided on the substrate, a color filter layer is provided on a side of the plurality of pixel structures away from the substrate, and the color filter layer includes a plurality of color filter blocks provided in one-to-one correspondence with the plurality of pixel structures;

[0009] each of the plurality of pixel structures emits light of one color, and the color of the light emitted by each pixel structure is the same as the color of the corresponding color filter block.

[0010] Optionally, the pixel structure includes a series-connected OLED composed of a plurality of electroluminescent structures.

[0011] Optionally, the pixel structure includes: a red light-emitting layer, a green light-emitting layer, a first electrical connection layer, and a blue light-emitting layer, which are sequentially disposed on the substrate substrate.

[0012] The first electroluminescent structure includes the red light-emitting layer and the green light-emitting layer, and the second electroluminescent structure includes the blue light-emitting layer; the first electroluminescent structure and the second electroluminescent structure are connected in series through the first electrical connection layer.

[0013] Optionally, the pixel structure includes: a red light-emitting layer, a second electrical connection layer, a green light-emitting layer, a first electrical connection layer, and a blue light-emitting layer, which are sequentially disposed on the substrate substrate.

[0014] The third electroluminescent structure includes the red light-emitting layer, the fourth electroluminescent structure includes the green light-emitting layer, and the second electroluminescent structure includes the blue light-emitting layer;

[0015] The third electroluminescent structure and the fourth electroluminescent structure are connected in series through the second electrical connection layer, and the fourth electroluminescent structure and the second electroluminescent structure are connected in series through the first electrical connection layer.

[0016] Optionally, the pixel unit further includes: a first electrode, the plurality of electroluminescent structures, and a second electrode, which are sequentially disposed on the substrate substrate.

[0017] The first electrode includes a reflective conductive layer, and the second electrode includes a semi-transmissive and semi-reflective conductive layer. The reflective conductive layer and the semi-transmissive and semi-reflective conductive layer form a resonant cavity.

[0018] Wherein, the distance between the reflective conductive layer and the semi-transmissive and semi-reflective conductive layer is the cavity length of the resonant cavity, and the wavelength of the light emitted by the pixel structure is positively correlated with the cavity length of the resonant cavity in the pixel structure.

[0019] Optionally, the first electrode includes: a first transparent conductive layer, the reflective conductive layer, an insulating layer, and a second transparent conductive layer, which are sequentially disposed on the substrate substrate.

[0020] The second transparent conductive layer is connected to the reflective conductive layer through a via hole in the insulating layer, and the wavelength of the light emitted by the pixel structure is positively correlated with the thickness of the insulating layer in the pixel structure.

[0021] Optionally, the first electrode includes: a first transparent conductive layer, the reflective conductive layer, and a second transparent conductive layer, which are sequentially disposed on the substrate substrate; the wavelength of the light emitted by the pixel structure is positively correlated with the thickness of the second transparent conductive layer in the pixel structure.

[0022] Optionally, the pixel structure further includes a functional film layer located between the first electrode and the second electrode. The functional film layer includes at least one of an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer. The wavelength of the light emitted by the pixel structure is positively correlated with the thickness of the functional film layer in the pixel structure.

[0023] Optionally, the cavity length of the resonant cavity in the pixel structure

[0024] where k is an integer, λ is the wavelength of the light emitted by the pixel structure, n is the average refractive index of the medium in the resonant cavity, and θ is the reflection angle of light on the reflective conductive layer in the pixel structure.

[0025] Optionally, the multiple pixel structures include a red light pixel structure for emitting red light, a green light pixel structure for emitting green light, and a blue light pixel structure for emitting blue light.

[0026] The k value corresponding to the cavity length of the first resonant cavity in the red light pixel structure is i, the k value corresponding to the cavity length of the second resonant cavity in the green light pixel structure is i, and the k value corresponding to the cavity length of the third resonant cavity in the blue light pixel structure is i, where i ≥ 1.

[0027] Optionally, the multiple pixel structures include a red light pixel structure for emitting red light, a green light pixel structure for emitting green light, and a blue light pixel structure for emitting blue light.

[0028] The k value corresponding to the cavity length of the first resonant cavity in the red light pixel structure is j, the k value corresponding to the cavity length of the second resonant cavity in the green light pixel structure is j, and the k value corresponding to the cavity length of the third resonant cavity in the blue light pixel structure is j + 1, where j ≥ 1.

[0029] On the other hand, a manufacturing method of a display panel is provided. The method includes:

[0030] Providing a substrate;

[0031] Forming multiple pixel structures on the substrate;

[0032] Forming a color filter layer on a side of the multiple pixel structures away from the substrate;

[0033] where the color filter layer includes multiple color filter blocks provided in one-to-one correspondence with the multiple pixel structures. Each pixel structure in the multiple pixel structures emits light of one color, and the color of the light emitted by each pixel structure is the same as the color of the corresponding color filter block.

[0034] Optionally, forming multiple pixel structures on the substrate includes:

[0035] When forming each pixel structure, a red light-emitting layer, a green light-emitting layer, a first electrical connection layer, and a blue light-emitting layer are sequentially formed on the substrate substrate;

[0036] Wherein, the red light-emitting layer and the green light-emitting layer form a first electroluminescent structure, and the blue light-emitting layer forms a second electroluminescent structure; the first electroluminescent structure and the second electroluminescent structure are connected in series through the first electrical connection layer, and the plurality of color light-emitting layers are connected in series with each other.

[0037] Optionally, forming a plurality of pixel structures on the substrate substrate includes:

[0038] When forming each pixel structure, a red light-emitting layer, a second electrical connection layer, a green light-emitting layer, a first electrical connection layer, and a blue light-emitting layer are sequentially formed on the substrate substrate;

[0039] Wherein, the red light-emitting layer forms a third electroluminescent structure, the green light-emitting layer forms a fourth electroluminescent structure, and the blue light-emitting layer forms a second electroluminescent structure; the third electroluminescent structure and the fourth electroluminescent structure are connected in series through the second electrical connection layer, and the fourth electroluminescent structure and the second electroluminescent structure are connected in series through the first electrical connection layer.

[0040] In another aspect, a display device is provided, and the display device includes the above-mentioned display panel.

[0041] The beneficial effects brought by the technical solution provided by this application at least include:

[0042] The display panel provided by the embodiment of the present invention includes: a plurality of pixel structures and a color filter layer, and each OLED is used to emit light of the same color as the corresponding color filter block set. Therefore, more light emitted by the OLED can pass through the color filter block, and the color purity of the display panel is higher, improving the display effect of the display panel. Description of the Drawings

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0044] Figure 1 It is a schematic structural diagram of the first display panel provided by the embodiment of the present invention;

[0045] Figure 2 It is a schematic structural diagram of the second display panel provided by the embodiment of the present invention;

[0046] Figure 3 It is a graph showing the relationship between the intensity and wavelength of light for the second display panel;

[0047] Figure 4 It is a gamut map of the second display panel;

[0048] Figure 5 It is a schematic structural diagram of the third display panel provided by the embodiment of the present invention;

[0049] Figure 6 It is a graph showing the relationship between the intensity and wavelength of light for the third display panel;

[0050] Figure 7 It is a gamut map of the third display panel;

[0051] Figure 8 It is a schematic structural diagram of the fourth display panel provided by the embodiment of the present invention;

[0052] Figure 9 It is a schematic structural diagram of the fifth display panel provided by the embodiment of the present invention;

[0053] Figure 10 It is a schematic structural diagram of the sixth display panel provided by the embodiment of the present invention;

[0054] Figure 11 It is a schematic structural diagram of a display panel provided by the related art;

[0055] Figure 12 It is a flowchart of a manufacturing method of a display panel according to an embodiment of the present invention;

[0056] Figure 13 It is a flowchart of a method for manufacturing an OLED according to an embodiment of the present invention;

[0057] Figure 14 It is a schematic diagram of the process of manufacturing the first OLED provided by the embodiment of the present invention;

[0058] Figure 15 It is a schematic diagram of the process of manufacturing the second OLED provided by the embodiment of the present invention;

[0059] Figure 16 It is a schematic diagram of the process of manufacturing the third OLED provided by the embodiment of the present invention;

[0060] Figure 17 It is a schematic diagram of the process of manufacturing the fourth OLED provided by the embodiment of the present invention;

[0061] Figure 18 It is a schematic diagram of the process of manufacturing the fifth OLED provided by the embodiment of the present invention;

[0062] Figure 19 The sixth process schematic diagram for manufacturing an OLED provided by an embodiment of the present invention. Detailed implementation manners

[0063] To make the objectives, technical solutions, and advantages of the present application clearer, the following will further describe the embodiments of the present application in detail with reference to the accompanying drawings.

[0064] Display devices have been widely used due to their fast response speed, full solidification, and self-luminescence characteristics. For example, display devices can be applied in the fields of flexible displays, transparent displays, and micro-displays, etc.

[0065] Among them, the applications of display devices in the micro-display field can include: augmented reality (AR) displays, head-mounted displays, stereoscopic viewers, and glasses-type displays, etc. The micro-display field requires display devices to have high color purity, brightness (such as brightness greater than 1500 nits), and color gamut. An embodiment of the present invention provides a display device. The display panel in this display device can be applied to the micro-display field, and this display device can also be applied to other display fields. The embodiments of the present invention do not limit this.

[0066] Figure 1 The structural schematic diagram of the first display panel provided by an embodiment of the present invention is as Figure 1 shown. The display panel 0 may include: a substrate 01.

[0067] A plurality of pixel structures 02 are disposed on the substrate 01. A color filter layer 03 is disposed on a side of the plurality of pixel structures 02 away from the substrate 01. The color filter layer 03 includes a plurality of color filter blocks 031 corresponding to the plurality of pixel structures 02 one by one. Each of the plurality of pixel structures 02 emits light of one color. For each of the plurality of pixel structures 02, the color of the light emitted by the pixel structure 02 is the same as the color of the corresponding color filter block 031.

[0068] It should be noted that each color filter block 031 corresponds to one color. The color filter block 031 only allows the light of its corresponding color to pass through and prohibits the light of the color not corresponding to it from passing through. The color of the color filter block 031 is also the color corresponding to the color filter block.

[0069] In summary, since the display panel provided by the embodiment of the present invention includes: a plurality of pixel structures and a color filter layer, and each OLED emits light of the same color as the corresponding color filter block, therefore, more light emitted by the pixel structures can pass through the color filter blocks, and the color purity of the display panel is higher, improving the display effect of the display panel.

[0070] Optionally, the material of the substrate may be silicon, or it may be other materials such as glass. The embodiments of the present invention do not limit this.

[0071] Optionally, the pixel structure 02 in the display panel 0 may also be a microcavity OLED, that is, the pixel structure 02 may include: a first electrode, a plurality of electroluminescent structures, and a second electrode sequentially arranged on the substrate. Among the two electrodes of the pixel structure 02, the first electrode (such as an anode) close to the substrate includes a reflective conductive layer, and the second electrode (such as a cathode) far from the substrate includes a semi-transmissive and semi-reflective conductive layer. These two electrodes can form a resonant cavity. The distance between the reflective conductive layer and the semi-transmissive and semi-reflective conductive layer is the cavity length of the resonant cavity, and the wavelength of the light emitted by the pixel structure is positively correlated with the cavity length of the resonant cavity in the pixel structure. It should be noted that the light rays emitted by all the light-emitting layers in the pixel structure 02 can form white light. The resonant cavity can screen a certain color of light in the white light for energy amplification and weaken the energy of other lights different from this color, so that the pixel structure 02 emits the light of this certain color, and the brightness of the light emitted by the pixel structure 02 is relatively high. The pixel structure 02 in the embodiments of the present invention can emit light of the same color as the corresponding color resist block 031 through the resonant cavity.

[0072] Optionally, the pixel structure 02 in the display panel 0 may include a tandem OLED composed of a plurality of electroluminescent structures. It should be noted that the tandem OLED has a relatively high luminous efficiency and a relatively high luminous power. Therefore, the display panel 0 provided by the embodiments of the present invention has both a relatively high luminous efficiency and a relatively high luminous power.

[0073] Exemplarily, the display panel provided by the embodiments of the present invention may have multiple implementation manners. Five of the implementation manners will be exemplified below.

[0074] Figure 2 This is a schematic structural diagram of the second display panel provided by the embodiments of the present invention. Figure 2 It shows the first implementation manner of the display panel. The pixel structure 02 in the display panel 0 may include: a first electrode 021, a red light-emitting layer 022, a green light-emitting layer 023, a first electrical connection layer 024, a blue light-emitting layer 025, and a second electrode 026 sequentially arranged on the substrate 01.

[0075] Among them, one of the first electrode 021 and the second electrode 026 may be a cathode, and the other may be an anode. In the embodiments of the present invention, it is taken as an example that the first electrode 021 is an anode and the second electrode 026 is a cathode. Exemplarily, a resonant cavity is formed between the first electrode 021 and the second electrode 026 in the OLED. For each OLED, the cavity length d of the resonant cavity in the OLED is related to the wavelength λ of the light emitted by the OLED.

[0076] For example, the relationship between the cavity length d and the wavelength λ can be: 2k(λ / 2) = 2ndcosθ, where k is an integer and can be referred to as the cavity length coefficient; n represents the average refractive index of the medium in the resonant cavity, and θ is the reflection angle of light on the reflective conductive layer in the OLED. Also, since the wavelength of light is related to the color of light, therefore, the cavity length is related to the color of light emitted by the OLED. By adjusting the cavity length d of the resonant cavity, the color of light emitted by the OLED can be adjusted. In the display panel 0, the wavelength of light emitted by the pixel structure is positively correlated with the cavity length of the resonant cavity in the pixel structure, and the cavity lengths of the resonant cavities in two pixel structures 02 that emit different colors of light are different.

[0077] In the embodiments of the present invention, the cavity length d of the resonant cavity in the pixel structure 02 can be adjusted by adjusting the thickness of the insulating layer in the first electrode 021 of the pixel structure 02. At this time, the wavelength of light emitted by the pixel structure is positively correlated with the thickness of the insulating layer in the pixel structure.

[0078] Exemplarily, the first electrode 021 may include: a first transparent conductive layer 0211, a reflective conductive layer 0212, an insulating layer 0213, and a second transparent conductive layer 0214 sequentially disposed on the substrate 01. And, the second transparent conductive layer 0214 is connected to the reflective conductive layer 0212 through a via ( Figure 2 not marked in the figure) on the insulating layer 0213. The materials of the first transparent conductive layer 0211 and the second transparent conductive layer 0214 can both be indium tin oxide, the material of the reflective conductive layer 0212 can be silver, the material of the insulating layer 0213 can be silicon dioxide, and the material of the semi-transmissive and semi-reflective conductive layer in the second electrode 026 can be a semi-transmissive and semi-reflective material doped with magnesium and silver. The thicknesses of the insulating layers 0213 in two pixel structures 02 that emit different lights are different, so that the cavity lengths of the resonant cavities in two pixel structures 02 that emit different lights are different.

[0079] Optionally, the k corresponding to the cavity length of the resonant cavity in each pixel structure 02 can be any integer, and when k takes any value, the wavelength of light emitted by the pixel structure is the same. In the embodiments of the present invention, on the premise that the pixel structure 02 emits a certain color of light through the resonant cavity, the cavity length of the resonant cavity in the pixel structure 02 can select the cavity length corresponding to any value of k. When the cavity length of the resonant cavity in the pixel structure 02 is short and the thicknesses of each film layer in the pixel structure 02 are also thin, the value of k corresponding to the cavity length of the resonant cavity can be appropriately increased to increase the cavity length of the resonant cavity and the thicknesses of each film layer in the pixel structure 02, which is convenient for the manufacture of the pixel structure 02.

[0080] Exemplarily, Figure 2The multiple pixel structures 02 in the display panel shown may include: a red light-emitting pixel structure 02 for emitting red light, a green light-emitting pixel structure 02 for emitting green light, and a blue light-emitting pixel structure 02 for emitting blue light. The k corresponding to the cavity length of the first resonant cavity in the red light-emitting pixel structure 02 may be i, the k corresponding to the cavity length of the second resonant cavity in the green light-emitting pixel structure 02 may be i, and the k corresponding to the cavity length of the third resonant cavity in the blue light-emitting pixel structure 02 and the third resonant cavity may be i, where i ≥ 1. That is, the k corresponding to the cavity length of the resonant cavity in these three pixel structures is all i. The thickness of the insulating layer in the red light-emitting pixel structure 02 may be 145 nanometers, the thickness of the insulating layer in the green light-emitting pixel structure 02 may be 90 nanometers, and the thickness of the insulating layer in the blue light-emitting pixel structure 02 may be 45 nanometers.

[0081] In addition, please continue to refer to Figure 2 , each pixel structure 02 may further include: a first hole injection layer (English: Hole Injection Layer; abbreviation: HIL) 027, a first hole transport layer (English: Hole Transport Layer; abbreviation: HTL) 028, a first electron transport layer (English: Electron Transport Layer; abbreviation: ETL) 029, a second hole injection layer B1, a second hole transport layer B2, a second electron transport layer B3, and an electron injection layer (English: Electron Injection Layer; abbreviation: EIL) B4. A thin film encapsulation (English: Thin Film Encapsulation; abbreviation: TFE) layer ( Figure 2 not shown in ) is also provided between the multiple pixel structures 02 and the color filter layer 03, and the color filter layer 03 further includes: a black matrix 032 located between the color filter blocks 031.

[0082] Among them, the thickness of the first transparent conductive layer 0211 may be 80 angstroms, the thickness of the reflective conductive layer 0212 may be 1000 angstroms, the thickness of the second transparent conductive layer 0214 may be 80 angstroms, the thickness of the first hole injection layer 027 may be 100 angstroms, the thickness of the first hole transport layer 028 may be 150 angstroms, the thickness of the red light-emitting layer 022 may be 100 angstroms, the thickness of the green light-emitting layer 023 may be 300 angstroms, the thickness of the first electron transport layer 029 may be 200 angstroms, the thickness of the first electrical connection layer 024 may be 150 angstroms, the thickness of the second hole injection layer B1 may be 100 angstroms, the thickness of the second hole transport layer B2 may be 100 angstroms, the thickness of the blue light-emitting layer 025 may be 250 angstroms, the thickness of the second electron transport layer B3 may be 300 angstroms, the thickness of the electron injection layer B4 may be 100 angstroms, and the thickness of the second electrode 026 may be 120 angstroms.

[0083] Furthermore, Figure 2Each pixel structure 02 in the display panel 0 shown may include a tandem OLED (also known as a stacked OLED). Please continue to refer to Figure 2 , in each pixel structure 02, the red light-emitting layer 022 is used to emit red light, the green light-emitting layer 023 is used to emit green light, and the blue light-emitting layer 025 is used to emit blue light. The red light-emitting layer 022 and the green light-emitting layer 023 are stacked together to form an electroluminescent structure, and the blue light-emitting layer 025 independently forms an electroluminescent structure. These two electroluminescent structures are electrically connected through a first electrical connection layer 024 located between the green light-emitting layer 023 and the blue light-emitting layer 025 to achieve the series connection of these two electroluminescent structures. That is, the red light-emitting layer and the green light-emitting layer form a first electroluminescent structure, the blue light-emitting layer forms a second electroluminescent structure, and the first electroluminescent structure is connected in series with the second electroluminescent structure through the first electrical connection layer.

[0084] For Figure 2 simulating the provided display panel, a curve graph as shown in Figure 3 can be obtained. The horizontal axis of this curve graph represents the wavelength of light in nanometers, and the vertical axis is the intensity of light (dimensionless). Please refer to Figure 3 , the wavelength of the red light emitted by the display panel is concentrated around 600 nanometers, the wavelength of the green light is concentrated around 520 nanometers, and the wavelength of the blue light is concentrated around 450 nanometers.

[0085] For Figure 2 simulating the provided display panel can also obtain the parameters shown in Table 1. Please refer to Table 1. The CIEx (i.e., the color coordinate x in the chromaticity diagram formulated by the Commission Internationale de L'Eclairage; hereinafter referred to as CIE) of the reddest light emitted by the display panel is 0.650, the CIEy (i.e., the color coordinate y in the chromaticity diagram formulated by CIE) is 0.341, and the CIEY (i.e., the luminance in the chromaticity standard formulated by CIE) is 66.0; the CIEx of the greenest light emitted by the display panel is 0.117, the CIEy is 0.771, and the CIEY is 79.6; the CIEx of the bluest light emitted by the display panel is 0.146, the CIEy is 0.032, and the CIEY is 66.8.

[0086] Table 1

[0087] Color of light CIEx CIEy CIEY Red 0.650 0.341 66.0 Green 0.117 0.771 79.6 Blue 0.146 0.032 66.8

[0088] According to the color coordinates in Table 1, the color gamut of the display panel in the chromaticity diagram formulated by CIE can be obtained (as shown in Figure 4in the color gamut A1). It can be seen that the display panel provided by the embodiment of the present invention reaches a color gamut of 120% in the color gamut standard formulated by the National Television Standards Committee (abbreviation: NTSC).

[0089] Optionally, to improve the brightness of the light emitted by the display panel, the transmittance of the color resist blocks in the embodiment of the present invention can be 50% - 60%, or a transmittance higher than 60%, and the embodiment of the present invention does not limit this. The total brightness of all the light emitted by the display panel can reach 2500 nits. However, the transmittance of the color resist blocks in the related art is often low, so the total brightness of all the light emitted by the display panel in the related art is low. For example, the total brightness is usually 300 nits.

[0090] It can be seen that the display panel provided by the embodiment of the present invention has high brightness, high color gamut and high color purity, and this display panel can meet the requirements of the microdisplay field for display devices.

[0091] Figure 5 This is a schematic structural diagram of the third display panel provided by the embodiment of the present invention. Figure 5 It shows the second implementable manner of the display panel.

[0092] As Figure 5 shown, on the basis of the display panel shown in Figure 2 shown, for the red pixel structure 02, k corresponding to the cavity length of the first resonant cavity can be j, for the green pixel structure 02, k corresponding to the cavity length of the second resonant cavity can be j, and for the blue pixel structure 02, k corresponding to the cavity length of the third resonant cavity can be j + 1, where j ≥ 1. Optionally, i and j can be equal or not equal. The thickness of the insulating layer in the red pixel structure 02 can be 90 nanometers, the thickness of the insulating layer in the green pixel structure 02 can be 18 nanometers, and the thickness of the insulating layer in the blue pixel structure 02 can be 120 nanometers.

[0093] For Figure 5 the display panel provided, simulation can obtain a curve graph as shown in Figure 6 shown. The horizontal axis of this curve graph represents the wavelength of light, with the unit of nanometer, and the vertical axis of this curve graph is the intensity of light, with the unit of W·m -2 ·nm -1 ·sr -1 . Please refer to Figure 6 , the wavelength of the red light emitted by the display panel is concentrated near 620 nanometers, the wavelength of the green light is concentrated near 520 nanometers, and the wavelength of the blue light is concentrated near 460 nanometers.

[0094] For Figure 5Simulating the provided display panel can also obtain the parameters shown in Table 2. Refer to Table 2. The CIEx of the reddest light emitted by the display panel is 0.673, the CIEy is 0.341, and the CIEY is 67.3; the CIEx of the greenest light emitted by the display panel is 0.157, the CIEy is 0.740, and the CIEY is 68.9; the CIEx of the bluest light emitted by the display panel is 0.142, the CIEy is 0.048, and the CIEY is 26.8.

[0095] Table 2

[0096] Color of light CIEx CIEy CIEY Red 0.673 0.341 67.3 Green 0.157 0.740 68.9 Blue 0.142 0.048 26.8

[0097] According to the color coordinates in Table 2, the color gamut of the display panel in the color gamut map defined by CIE can be obtained (such as Figure 7 the color gamut A2 in). It can be seen that the display panel provided by the embodiment of the present invention reaches a color gamut of 115% in the color gamut standard defined by NTSC. In addition, the total brightness of all the light emitted by the display panel can reach 2200 nits.

[0098] Figure 8 FIG. 15 is a schematic structural diagram of a fourth display panel provided by an embodiment of the present invention, Figure 8 showing a third implementable manner of the display panel.

[0099] As Figure 8 shown, on the basis of the display panel shown in Figure 5 each of the multiple electroluminescent structures in each pixel structure 02 can also be different from Figure 5 the multiple electroluminescent structures in. By way of example, in each pixel structure 02 shown in Figure 8 the red light-emitting layer 022 independently forms an electroluminescent structure, the green light-emitting layer 023 independently forms another electroluminescent structure, and the blue light-emitting layer 025 independently forms yet another electroluminescent structure. At this time, a second electrical connection layer B5 can be provided between the red light-emitting layer 022 and the green light-emitting layer 023. The red light-emitting layer 022 can be electrically connected to the green light-emitting layer 023 through the second electrical connection layer B5, and the green light-emitting layer 023 can be electrically connected to the blue light-emitting layer 025 through the first electrical connection layer 024 to achieve the series connection of these three electroluminescent structures. That is, the red light-emitting layer forms a third electroluminescent structure, the green light-emitting layer forms a fourth electroluminescent structure, and the blue light-emitting layer forms a second electroluminescent structure; the third electroluminescent structure is serially connected to the fourth electroluminescent structure through the second electrical connection layer, and the fourth electroluminescent structure is serially connected to the second electroluminescent structure through the first electrical connection layer.

[0100] Please continue to refer to Figure 8, the second electrical connection layer B5 can be composed of a second electron transport layer B6, a third hole injection layer B7, and a third hole transport layer B8, which are stacked in sequence, and the electron transport layer is disposed close to the red light emitting layer 022. The thickness of the second electron transport layer B6 can be 300 angstroms, the thickness of the third hole injection layer B7 can be 100 angstroms, and the thickness of the third hole transport layer B8 can be 150 angstroms.

[0101] For Figure 8 Simulating the provided display panel, the color gamut achieved by the display panel in the color gamut standard formulated by NTSC, the total brightness of all the light emitted by the display panel, and the color purity of the light emitted by the display panel can be obtained. Moreover, in the third implementation manner, the color gamut, total brightness, and color purity of the display panel are all relatively high.

[0102] Figure 9 It is a schematic structural diagram of the fifth display panel provided by the embodiment of the present invention. Figure 9 It shows the fourth implementation manner of the display panel.

[0103] As Figure 9 shown, on the basis of the display panel shown in Figure 2 The first electrode 021 in each pixel structure 02 may not include an insulating layer, but only includes a first transparent conductive layer 0211, a reflective conductive layer 0212, and a second transparent conductive layer 0214, which are sequentially disposed on the substrate 01. At this time, the cavity length d of the resonant cavity in the pixel structure 02 can be adjusted by adjusting the thickness of the second transparent conductive layer 0214 in the first electrode 021 of the pixel structure 02. The thicknesses of the second transparent conductive layers 0214 in two pixel structures 02 that emit different lights are different. At this time, the wavelength of the light emitted by the pixel structure is positively correlated with the thickness of the second transparent conductive layer in the pixel structure.

[0104] The thickness of the second transparent conductive layer in the red light pixel structure 02 can be 100 nanometers, the thickness of the second transparent conductive layer in the green light pixel structure 02 can be 26 nanometers, and the thickness of the second transparent conductive layer in the blue light pixel structure 02 can be 130 nanometers.

[0105] Figure 10 It is a schematic structural diagram of the sixth display panel provided by the embodiment of the present invention. Figure 10 It shows the fifth implementation manner of the display panel.

[0106] As Figure 10 shown, in Figure 2Based on the display panel shown, the thicknesses of the insulating layers 0213 in two pixel structures 02 that emit different lights can be the same. Moreover, at least one of the film layers in the OLED, such as the electron injection layer B4, the electron transport layer (such as the first electron transport layer 029 and the second electron transport layer B3), the hole injection layer (such as the first hole injection layer 027 and the second hole injection layer B1), and the hole transport layer (such as the first hole transport layer 028 and the second hole transport layer B2), is a functional film layer, and the thicknesses of the functional film layers in two OLEDs that emit different lights are different. In the embodiments of the present invention, taking the functional film layer including the electron injection layer B4 as an example, the thicknesses of the electron injection layer B4 in two OLEDs that emit different lights are different. Optionally, the functional film layer may further include other film layers (such as the first hole injection layer 027, etc.), and the embodiments of the present invention do not limit this. At this time, the cavity length d of the resonant cavity in the pixel structure 02 can be adjusted by adjusting the thickness of the functional film layer in the pixel structure 02.

[0107] The display panel provided by the embodiments of the present invention will be compared with the display panel provided in the related art below.

[0108] Exemplarily, the related art provides two OLED display panels. Among them, one OLED display panel includes a substrate, and a plurality of OLEDs are provided on the substrate. A color filter layer is further provided on the side of the plurality of OLEDs away from the substrate. The plurality of OLEDs can all emit white light, and the color filter layer includes a plurality of color filter blocks corresponding to the plurality of OLEDs one by one.

[0109] However, since the light emitted by the OLED is white light, and the light that can pass through the color filter block in the white light is less. For example, the red light that can pass through the red color filter block in the white light is less, the green light that can pass through the green color filter block in the white light is less, and the blue light that can pass through the blue color filter block in the white light is less. Therefore, the colors of the light emitted by the display panel are all lighter, and the color purity of the light emitted by the display panel is lower. In the embodiments of the present invention, since the color of the light emitted by the OLED is the same as the color of the color filter block corresponding to the OLED, that is, the light that can pass through the color filter block in the light emitted by the OLED is more, the colors of the light emitted by the display panel are all darker, and the color purity of the light emitted by the display panel is higher.

[0110] Figure 11 FIG. is a schematic structural diagram of another OLED display panel provided by the related art. As Figure 11 shown, the OLED display panel 1 includes a substrate 10, and a plurality of OLEDs 11 are provided on the substrate 10. Each OLED 11 can emit a light of one color, and the plurality of OLEDs 11 can emit red light, green light, and blue light.

[0111] However, the wavelength range of the light emitted by each OLED 11 is relatively large, and the light usually contains light of other colors. For example, an OLED 11 is required to emit red light, but the light emitted by this OLED 11 usually contains a little yellow light. In this way, the purity of the light emitted by each OLED 11 is relatively low. In the embodiment of the present invention, since a color resist block is correspondingly arranged on one side of each OLED away from the substrate, the color resist block can filter the light emitted by the OLED, thereby removing the light of other colors mixed in the light and improving the purity of the light emitted by the display panel.

[0112] In addition, it should be noted that when manufacturing a display panel as Figure 11 shown, a high-precision fine metal mask (English: Fine Metal Mask; abbreviation: FMM) needs to be used. And due to the limitation of the precision of the FMM, in the related art, it is impossible to manufacture an OLED with a small orthographic projection area on the substrate. Therefore, the number of pixels per inch (English: Pixels Per Inch; abbreviation: PPI) in the display panel is small.

[0113] When manufacturing the display panel provided in the embodiment of the present invention, the FMM is not required. Therefore, the manufacturing process of the display panel is not limited by the FMM. So, the PPI of the display panel provided in the embodiment of the present invention is large. For example, the PPI of the display panel in the embodiment of the present invention can reach 6000, while the PPI of the display panel in the related art is less than 6000, such as about 2000.

[0114] In addition, the display panel provided in the embodiment of the present invention can reach a color gamut greater than 100% in the color gamut standard formulated by NTSC.

[0115] It should be noted that the arrangement order of the respective light-emitting layers in the pixel structure in the embodiment of the present invention is only an example. Optionally, the arrangement order of the respective light-emitting layers can also be adjusted, and the embodiment of the present invention does not limit this.

[0116] In summary, since the display panel provided in the embodiment of the present invention includes: a plurality of pixel structures and a color resist layer, and each OLED is used to emit light of the same color as the color resist block corresponding to it, therefore, more light emitted by the OLED can pass through the color resist block, the color purity of the display panel is relatively high, and the display effect of the display panel is improved.

[0117] Figure 12 It is a flowchart of a manufacturing method of a display panel provided in an embodiment of the present invention. This method can be used to manufacture Figure 1 、 Figure 2 、 Figure 5 、 Figure 8 、 Figure 9 andFigure 10 Any of the shown display panels. As Figure 12 shown, the manufacturing method of the display panel may include:

[0118] Step 1201: Provide a substrate.

[0119] Step 1202: Form a plurality of pixel structures on the substrate.

[0120] Step 1203: Form a color filter layer on the side of the plurality of pixel structures away from the substrate.

[0121] Among them, the color filter layer includes a plurality of color filter blocks arranged in one-to-one correspondence with the plurality of pixel structures. Each pixel structure in the plurality of pixel structures emits light of one color, and the color of the light emitted by each pixel structure is the same as the color of the corresponding color filter block.

[0122] In summary, since the display panel manufactured by the method provided in the embodiment of the present invention includes: a plurality of pixel structures and a color filter layer, and each OLED is used to emit light of the same color as the corresponding color filter block, therefore, more light emitted by the OLED can pass through the color filter block, the color purity of the display panel is higher, and the display effect of the display panel is improved.

[0123] It should be noted that the display panel manufactured by the method provided in the embodiment of the present invention can have multiple implementation manners. For example, Figure 2 , Figure 5 , Figure 8 , Figure 9 and Figure 10 shown implementation manners, etc. The manufacturing methods of the display panel in these implementation manners are similar. In the embodiment of the present invention, only the display panel shown in Figure 2 is taken as an example for explanation.

[0124] For example, when manufacturing the display panel shown in Figure 2 , as Figure 13 shown, step 1202 may include:

[0125] Step 12021: Form a first transparent conductive layer and a reflective conductive layer on the substrate in sequence.

[0126] Optionally, as Figure 14 shown, when manufacturing the first transparent conductive layer 0211, methods such as coating, magnetron sputtering, thermal evaporation, or plasma enhanced chemical vapor deposition (English: Plasma Enhanced Chemical Vapor Deposition; abbreviation: PECVD) can be used to deposit a layer of transparent conductive material on the substrate 01 to obtain a transparent conductive material layer ( Figure 14(not shown in the figure), and then the first transparent conductive layer 0211 can be obtained by processing the transparent conductive material layer using a single lithography process.

[0127] Among them, the single lithography process includes: photoresist coating, exposure, development, etching, and photoresist stripping. Therefore, processing the transparent conductive material layer using a single lithography process includes: coating a layer of photoresist on the transparent conductive material layer, and then using a mask to expose the photoresist to form a completely exposed area and a non-exposed area. After that, a development process is used for treatment to remove the photoresist in the completely exposed area and retain the photoresist in the non-exposed area. Then, the corresponding area of the completely exposed area on the transparent conductive material layer is etched, and after the etching is completed, the photoresist in the non-exposed area is stripped to obtain the first transparent conductive layer 0211.

[0128] After forming the first transparent conductive layer 0211, a reflective conductive material layer ( Figure 14 not shown in the figure) can be formed on the substrate 01 with the first transparent conductive layer 0211 formed thereon, and then the reflective conductive layer 0212 as shown in Figure 14 can be obtained by processing the reflective conductive material layer using a single lithography process.

[0129] Step 12022: Form an insulating layer on the substrate on which the first transparent conductive layer and the reflective conductive layer are formed.

[0130] It should be noted that multiple pixel structures capable of emitting light of multiple colors need to be formed on the substrate, and Figure 2 in the shown display panel, the color of the light emitted by the OLED is adjusted by adjusting the thickness of the insulating layer. Therefore, in step 12022, an insulating layer with multiple thicknesses needs to be formed on the substrate. For example, OLEDs capable of emitting red light, green light, and blue light need to be formed on the substrate. Therefore, in step 12022, an insulating layer with three thicknesses needs to be formed on the substrate. For example, the thickness of the insulating layer in the OLED emitting red light is the largest, and the thickness of the insulating layer in the OLED emitting blue light is the smallest.

[0131] The process of forming the insulating layer on the substrate can be as shown in Figures 15 to 18 . Please refer to Figures 15 to 18 . When forming the insulating layer 0213, an insulating material layer and a photoresist layer can be sequentially formed on the substrate 01 with the first transparent conductive layer 0211 and the reflective conductive layer 0212 formed thereon ( Figures 15 to 18 neither the insulating material layer nor the photoresist layer is shown in the figure).

[0132] Then, a photomask is used to expose the photoresist layer, so that the photoresist layer forms a completely exposed area and a non-exposed area, where the non-exposed area is the corresponding area of the reflective conductive layer 0212 in the photoresist layer. After that, a developing process is performed to remove the photoresist in the completely exposed area and retain the photoresist in the non-exposed area. Then, the corresponding area of the completely exposed area on the insulating material layer is etched. After the etching is completed, the photoresist in the non-exposed area is peeled off, and the first insulating layer pattern C1 and the first photoresist pattern C2 as shown in Figure 15 can be obtained.

[0133] Further, after obtaining the first insulating layer pattern C1 and the first photoresist pattern C2, a halftone mask can be used to expose and develop the first photoresist pattern C2 to remove the photoresist in the area where the minimum thickness insulating layer is to be formed and thin the photoresist in the area where the second minimum thickness insulating layer is to be formed, so as to obtain the second photoresist pattern C3 as shown in Figure 16 . The second photoresist pattern C3 includes: a first thickness area C31, a second thickness area C32, and a photoresist completely removed area C33. The thickness of the photoresist in the first thickness area C31 is greater than the thickness of the photoresist in the second thickness area C32. The first thickness area C31 is the corresponding area of the maximum thickness insulating layer to be formed in the second photoresist pattern C3.

[0134] After that, the first insulating layer pattern C1 can be etched using the second photoresist pattern C3 as a mask, for example, by dry etching. During the etching process, the first insulating layer pattern C1 corresponding to the photoresist completely removed area C33 is thinned, and the second thickness area C32 and its corresponding first insulating layer pattern C1 are both thinned. Then, the first thickness area C31 is peeled off, and the second insulating layer pattern C4 as shown in Figure 17 can be obtained.

[0135] Finally, as shown in Figure 18 , vias C5 can be formed in the second insulating layer pattern C4, so that insulating layers 0213 with three thicknesses can be obtained. These three thicknesses of insulating layers 0213 respectively correspond to the first thickness area C31, the second thickness area C32, and the photoresist completely removed area C33 in the second photoresist pattern C3.

[0136] Optionally, step 12022 can also be implemented in other ways. For example, insulating layers with three different thicknesses can be formed in sequence, and the embodiments of the present invention do not limit this.

[0137] Step 12023: On a substrate having an insulating layer formed thereon, sequentially form a second transparent insulating layer, a first hole injection layer, a first hole transport layer, a red light-emitting layer, a green light-emitting layer, a first electron transport layer, a first electrical connection layer, a second hole injection layer, a second hole transport layer, a blue light-emitting layer, a second electron transport layer, an electron injection layer, and a second electrode.

[0138] The formation process of each film layer to be formed in Step 12023 may include: coating the material layer of the film layer, and then processing the material layer through a single patterning process, and this process may refer to the process of manufacturing the first transparent conductive layer or the reflective conductive layer in Step 12021.

[0139] After sequentially forming the second transparent insulating layer, the first hole injection layer, the first hole transport layer, the red light-emitting layer, the green light-emitting layer, the first electron transport layer, the first electrical connection layer, the second hole injection layer, the second hole transport layer, the blue light-emitting layer, the second electron transport layer, the electron injection layer, and the second electrode, the structure as shown in Figure 19 can be obtained. Exemplarily, Figure 19 the structure shown includes: a red pixel structure capable of emitting red light, a green pixel structure capable of emitting green light, and a blue pixel structure capable of emitting blue light.

[0140] It should be noted that after manufacturing a plurality of pixel structures, a TFE layer needs to be formed on the substrate having the plurality of pixel structures formed thereon. In Step 1203, a color resist layer can be formed on the TFE layer.

[0141] In summary, since the display panel manufactured by the method provided in the embodiment of the present invention includes: a plurality of pixel structures and a color resist layer, and each OLED emits light of the same color as the corresponding color resist block set, therefore, more light emitted by the OLED can pass through the color resist block, the color purity of the display panel is higher, and the display effect of the display panel is improved.

[0142] The embodiment of the present invention provides a display device, which may include Figure 1 、 Figure 2 、 Figure 5 、 Figure 8 、 Figure 9 and Figure 10 any of the display panels shown. Exemplarily, the display device may be: an electronic paper, a mobile phone, a tablet computer, a television, a monitor, a notebook computer, a digital photo frame, a navigator, or any other product or component having a display function.

[0143] It should be noted that the method embodiments provided by the embodiments of the present invention can be mutually referred to with the corresponding display panel and display device embodiments, and the embodiments of the present invention do not make any limitations in this regard. The sequence of steps of the method embodiments provided by the embodiments of the present invention can be appropriately adjusted, and the steps can also be increased or decreased accordingly according to the situation. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of the changed methods, which should all be covered within the protection scope of the present invention, and thus will not be elaborated herein.

[0144] The above are only optional embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A display panel, characterized in that, The display panel includes: a substrate; a plurality of pixel structures located on the substrate; a color filter layer located on a side of the plurality of pixel structures away from the substrate, the color filter layer including a plurality of color filter blocks, and the color filter blocks corresponding to one or more of the plurality of pixel structures; each pixel structure of the plurality of pixel structures emits light of one color, and the color of the light emitted by each pixel structure is the same as the color of the corresponding color filter block; each pixel structure of the plurality of pixel structures includes a plurality of electroluminescent structures connected in series; the pixel structure includes: a red light-emitting layer, a second electrical connection layer, a green light-emitting layer, a first electrical connection layer, and a blue light-emitting layer sequentially disposed on the substrate; the plurality of electroluminescent structures include a first electroluminescent structure and a second electroluminescent structure, the first electroluminescent structure includes the red light-emitting layer, the second electroluminescent structure includes the green light-emitting layer, and the first electroluminescent structure and the second electroluminescent structure are connected in series through the second electrical connection layer; the plurality of electroluminescent structures further include a third electroluminescent structure, and the second electroluminescent structure and the third electroluminescent structure are connected in series through the first electrical connection layer; the pixel structure further includes a first electrode and a second electrode; the first electrode, the plurality of electroluminescent structures, and the second electrode are sequentially stacked on the substrate, the first electrode includes a reflective conductive layer, the second electrode includes a semi-transmissive and semi-reflective conductive layer, and the distance between the reflective conductive layer and the semi-transmissive and semi-reflective conductive layer is positively correlated with the wavelength of the light emitted by the pixel structure.

2. The display panel according to claim 1, wherein The distance d between the reflective conductive layer and the semi-transmissive and semi-reflective conductive layer satisfies: wherein, the coefficient k is a positive integer, λ is the wavelength of the light emitted by the pixel structure, n is the average refractive index of the medium between the reflective conductive layer and the semi-transmissive and semi-reflective conductive layer, and θ is the reflection angle of light on the reflective conductive layer in the pixel structure.

3. The display panel according to claim 2, wherein The plurality of pixel structures include: a red light pixel structure for emitting red light, a green light pixel structure for emitting green light, and a blue light pixel structure for emitting blue light, the k corresponding to the red light pixel structure is i, the k corresponding to the green light pixel structure is i, the k corresponding to the blue light pixel structure is i, and i≥1.

4. The display panel according to claim 2, wherein, The plurality of pixel structures include: a red light pixel structure for emitting red light, a green light pixel structure for emitting green light, and a blue light pixel structure for emitting blue light, the k corresponding to the red light pixel structure is j, the k corresponding to the green light pixel structure is j, the k corresponding to the blue light pixel structure is j + 1, and j≥1.

5. The display panel according to claim 1, wherein The first electrode includes: a first transparent conductive layer, the reflective conductive layer, an insulating layer, and a second transparent conductive layer sequentially disposed on the substrate; the second transparent conductive layer is connected to the reflective conductive layer through a via hole in the insulating layer, and the wavelength of the light emitted by the pixel structure is positively correlated with the thickness of the insulating layer in the pixel structure.

6. The display panel according to claim 1, characterized in that, The first electrode includes: a first transparent conductive layer, the reflective conductive layer, and a second transparent conductive layer, which are sequentially disposed on the substrate; the wavelength of the light emitted by the pixel structure is positively correlated with the thickness of the second transparent conductive layer in the pixel structure.

7. The display panel according to claim 1, wherein The pixel structure further includes a functional film layer located between the first electrode and the second electrode. The functional film layer includes at least one of an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer. The wavelength of the light emitted by the pixel structure is positively correlated with the thickness of the functional film layer in the pixel structure.

8. A display device, characterized in that, The display device includes the display panel according to any one of claims 1 to 7.

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