Display panel, display device, and method of manufacturing display panel

Abstract

An embodiment of the present disclosure provides a display panel 20. The display panel 20 includes a substrate 21, a light-emitting functional layer 22 disposed on the substrate 21, a filter layer 24 disposed on a side of the light-emitting functional layer 22 facing away from the substrate 21, and a plurality of light-collecting elements 26 disposed on a side of the filter layer 24 facing away from the substrate 21, the filter layer 24 including a plurality of filter units 241, at least one of the plurality of filter units 241 configured to diverge at least a portion of light from the light-emitting functional layer 22, and the plurality of light-collecting elements 26 configured to converge light from the plurality of filter units 241. An embodiment of the present disclosure further provides a display device 800 including the display panel 20 and a method for manufacturing the display panel 20.

Description

[Technical Field]

[0001] The present disclosure relates to the field of display technology, and more particularly to a display panel, a display device, and a method for manufacturing a display panel. [Background technology]

[0002] Organic Light-Emitting Diode (OLED) displays, also known as organic electroluminescent displays, are different from conventional liquid crystal displays (LCDs). This display technology has advantages such as simple structure, self-luminescence, high contrast, thin thickness, wide viewing angle, fast response speed, continuously adjustable emission color, and use in flexible panels, making it one of the important development directions for new generation display devices and attracting increasing attention.

[0003] However, due to manufacturing processes and other reasons, the performance of OLED display devices still needs to be improved. Summary of the Invention

[0004] Embodiments of the present disclosure provide a display panel, a display device, and a method for manufacturing a display panel.

[0005] One aspect of the present disclosure provides a display panel, which may include a substrate, a light-emitting functional layer disposed on the substrate, a filter layer disposed on a side of the light-emitting functional layer facing away from the substrate, and a plurality of light-collecting elements disposed on a side of the filter layer facing away from the substrate, wherein at least one filter unit of the plurality of filter units is designed to diverge at least a portion of light from the light-emitting functional layer, and the plurality of light-collecting elements are configured to converge light from the plurality of filter units.

[0006] In some embodiments of the display panel, orthogonal projections of the plurality of filter units onto the substrate may overlap with orthogonal projections of the plurality of light-collecting elements onto the substrate, respectively.

[0007] In some embodiments of the display panel, the plurality of filter units include at least one first color filter unit, at least one second color filter unit, and at least one third color filter unit, and at least one of the first color filter unit, the second color filter unit, and the third color filter unit may be designed to diverge at least a portion of the light from the light-emitting functional layer.

[0008] In some embodiments of the display panel, only one of the first color filter unit, the second color filter unit and the third color filter unit may be designed to diverge at least a portion of the light from the light-emitting functional layer.

[0009] In some embodiments of the display panel, two of the first color filter unit, the second color filter unit, and the third color filter unit may be designed to diverge at least a portion of the light from the light-emitting functional layer.

[0010] In some embodiments of the display panel, the first color filter unit, the second color filter unit and the third color filter unit may all be designed to diverge at least a portion of the light from the light-emitting functional layer.

[0011] In some embodiments of the display panel, each filter unit of the plurality of filter units may include a first surface facing the light-emitting functional layer and a second surface facing away from the light-emitting functional layer, and at least one of the first surface and the second surface of at least one filter unit designed to diverge at least some of the light from the light-emitting functional layer may be concave.

[0012] In some embodiments of the display panel, the second surface of at least one filter unit designed to diverge at least a portion of the light from the light-emitting functional layer may be concave and the first surface thereof may be flat, and the first surface and the second surface of the remaining filter units other than the filter unit designed to diverge at least a portion of the light from the light-emitting functional layer may both be flat.

[0013] In some embodiments of the display panel, the concave surface may be a concave spherical surface.

[0014] Some embodiments of the display panel may have an overlay between adjacent filter units of the plurality of filter units.

[0015] In some embodiments of the display panel, the focusing element may be a focusing lens or a focusing prism.

[0016] In some embodiments of the display panel, the collecting lens may be a plano-convex lens with a planar light entrance surface facing the filter layer and an arc-shaped light exit surface facing away from the filter layer.

[0017] In some embodiments of the display panel, the radius of curvature of the concave spherical surface may be greater than the radius of curvature of the arc-shaped light-exiting surface of the plano-convex lens.

[0018] In some embodiments of the display panel, the radius of curvature of the concave spherical surface may be approximately 1.6 to 2.4 μm, and the radius of curvature of the arc-shaped light-emitting surface of the plano-convex lens may be approximately 1.0 to 1.9 μm.

[0019] In some embodiments of the display panel, the refractive index difference between the media located on either side of the concave spherical surface is greater than the refractive index difference between the media located on either side of the arc-shaped light exit surface of the plano-convex lens.

[0020] In some embodiments of the display panel, there may be gaps between adjacent ones of the plurality of light-collecting elements.

[0021] In some embodiments of the display panel, the display panel may further include a planarization layer located between the filter layer and the plurality of light-collecting elements.

[0022] In some embodiments of the display panel, the refractive index of the filter layer may be greater than the refractive index of the planarization layer and the refractive index of the focusing element.

[0023] In some embodiments of the display panel, the filter layer may have a refractive index of about 1.6 to 1.75, the light-collecting element may have a refractive index of about 1.56 to 1.60, and the planarization layer may have a refractive index of about 1.44 to 1.55.

[0024] In some embodiments of the display panel, the display panel may further include a plurality of first electrodes and a plurality of second electrodes insulated from each other and positioned between the substrate and the filter layer, wherein the second electrode may be positioned on a side of the plurality of first electrodes that is away from the substrate.

[0025] In some embodiments of the display panel, the orthogonal projection of the plurality of first electrodes onto the substrate may partially overlap with the orthogonal projection of the plurality of focusing elements onto the substrate, and the distance in a direction parallel to the substrate between the center of each first electrode and the center of the focusing element that partially overlaps with its orthogonal projection may be greater than zero.

[0026] Another aspect of the present disclosure provides a display device, the display device including a display panel according to any of the detailed embodiments of the present disclosure.

[0027] In yet another aspect of the present disclosure, there is provided a method for manufacturing a display panel according to any of the detailed embodiments of the present disclosure, the method including: providing a substrate; forming a light-emitting functional layer on the substrate; forming a filter layer on the light-emitting functional layer; and forming a plurality of focusing elements on the filter layer, the filter layer including a plurality of filter units, wherein at least one filter unit of the plurality of filter units is designed to diverge at least a portion of light from the light-emitting functional layer, and the plurality of focusing elements are configured to converge light from the plurality of filter units.

[0028] In an embodiment of the method, forming a plurality of focusing elements on the filter layer includes forming a planarization layer on the filter layer and forming a plurality of focusing elements on the planarization layer.

[0029] Further aspects and scope of applicability will become apparent from the description provided herein. It is to be understood that various aspects herein can be implemented alone or in combination with one or more other aspects. It should also be understood that the description and specific embodiments herein are intended for illustrative purposes and are not intended to limit the scope of the present disclosure.

[0030] The drawings described herein are for purposes of illustrating selected examples only, not all possible embodiments, and are not intended to limit the scope of the present disclosure. [Brief explanation of the drawings]

[0031] [Figure 1A] 1 illustrates a schematic diagram of an example display panel having multiple lenses. [Figure 1B] 1B shows a schematic diagram of the optical path in the display panel of FIG. 1A. [Figure 2] 1 illustrates a schematic diagram of an optical path of a display panel and portions thereof in accordance with one or more embodiments of the present disclosure. [Figure 3]3 illustrates a schematic diagram of equivalent optical paths for the display panel of FIG. 2 in accordance with one or more embodiments of the present disclosure. [Figure 4] 10A-10C schematically illustrate monochromatic viewing angle simulation diagrams of a concave filter unit and a planar filter unit in accordance with one or more embodiments of the present disclosure. [Figure 5] 10A and 10B schematically illustrate another display panel and its optical path diagram in accordance with one or more embodiments of the present disclosure. [Figure 6] 10A and 10B schematically illustrate yet another display panel and its optical path diagram in accordance with one or more embodiments of the present disclosure. [Figure 7] 1 illustrates a schematic diagram of a display device in accordance with one or more embodiments of the present disclosure. [Figure 8] 1 illustrates a flowchart of a method for manufacturing a display panel in accordance with one or more embodiments of the present disclosure. [Figure 9] 1 shows a schematic diagram of a display panel arrangement and its optical path diagram for a viewing angle range with an offset. [Figure 10] 10A and 10B schematically illustrate yet another display panel 80 and its optical path diagram in accordance with one or more embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0032] Corresponding reference numerals indicate corresponding parts and features throughout the various views of the above drawings.

[0033] Various embodiments of the present disclosure will now be described in detail with reference to the drawings, which are provided as examples to enable those skilled in the art to realize the present disclosure.

[0034] It should be noted that the following drawings and examples are not intended to limit the scope of the present disclosure. When specific components of the present disclosure can be partially or completely realized using known components (or methods or processes), only those parts of such known components (or methods or processes) necessary for understanding the present disclosure will be described, and detailed descriptions of other parts of such known components will be omitted so as not to confuse the present disclosure. Furthermore, various embodiments illustratively include currently and future known equivalents to the components related to this specification.

[0035] Unless expressly stated otherwise, the singular forms of words used in this specification and the appended claims include the plural, and vice versa. Thus, reference to the singular normally includes the plural of the corresponding term. Similarly, the terms "comprise," "include," "have," and "have" and grammatical variations thereof are intended to be inclusive and mean that there may be additional elements other than the listed elements. When the term "exemplary," when used herein, particularly when positioned after a set of terms, "exemplary" is exemplary and descriptive and should not be considered exclusive or extensive.

[0036] As used herein, the term "located above" does not imply that the final stack in a display panel or display device has a particular geometric orientation relative to the direction of gravity, but rather refers to a stack manufacturing method that indicates that after manufacturing, the stack may typically be placed in any geometric orientation, including upside down. The terms "first," "second," "third," etc. are used for descriptive purposes only and are not understood to indicate or imply relative importance and order of formation.

[0037] As used in the full text, each range is used in shorthand to avoid a detailed description of each numerical value within the range. Where appropriate, any suitable value within the range can be selected as the upper value, lower value, or end value of the range.

[0038] An OLED display panel typically consists of a substrate, cathode, anode, hole injection layer (HIL), electron injection layer (EIL), hole transport layer (HTL), electron transport layer (ETL), and light emitting layer (EML). Under the action of an electric field, holes generated at the anode and electrons generated at the cathode move and are injected into the hole transport layer and electron transport layer, respectively, before moving to the light emitting layer. When the two meet in the light emitting layer, energy excitons are generated, which excite the light emitting molecules and ultimately generate visible light.

[0039] Brightness and viewing angle are important optical indices for measuring the performance of a display panel. In some technologies, to achieve higher display brightness, display panels typically use several focusing elements to focus the light emitted by the light-emitting layer onto the center of each pixel. In this way, the brightness of each subpixel can be increased to enhance the overall brightness of the display panel. In particular, microdisplay panels use multiple microlenses for each subpixel, which can enhance brightness through the light focusing effect of the microlenses.

[0040] FIG. 1A schematically illustrates an example display panel having multiple lenses. FIG. 1B schematically illustrates the optical path in the display panel of FIG. 1A. Referring to FIG. 1A, the display panel may include multiple lenses 16. The lenses 16 may correspond one-to-one to the subpixels of the display panel. Specifically, the lenses 16 may correspond one-to-one to the filter units 141 in the filter layer 14 of the display panel. Referring to FIG. 1B, the light-emitting functional layer 12 of the display panel can be regarded as a planar light source, and light emitted from the light-emitting functional layer 12 passes through the filter layer 14 essentially vertically. After passing through the filter layer, the light is incident on the multiple lenses 16 located above the filter layer 14. Each of the lenses 16 converges the incident light toward the center of the corresponding subpixel, thereby increasing the brightness of the subpixel.

[0041] However, the convergence of light by the lens 16 reduces the viewing angle of the display panel, which is particularly noticeable in micro display panels, which have high requirements for viewing angles.

[0042] In order to ensure the brightness of the display panel while not significantly impairing the viewing angle of the display panel, some embodiments of the present disclosure provide a display panel, which can increase the viewing angle by changing the shape of the filter units in the filter layer.

[0043] In this specification, the term "subpixel" refers to a basic functional unit for displaying an image, which may include a pixel electrode, a common electrode portion facing the pixel electrode, a portion of a light-emitting functional layer located between the pixel electrode and the corresponding portion of the common electrode, and a corresponding filter unit (red, green, or blue). Thus, a single filter element is one of the components of a single subpixel. However, for convenience, in some parts of this specification, the terms "filter unit" and "subpixel" are not strictly distinguished and may be used interchangeably.

[0044] Some embodiments of the present disclosure provide a display panel, which may include a substrate, a light-emitting functional layer located on the substrate, a filter layer located on a side of the light-emitting functional layer facing away from the substrate, and a plurality of focusing elements located on a side of the filter layer facing away from the substrate, wherein at least one filter unit of the plurality of filter units is designed to diverge at least a portion of light from the light-emitting functional layer, and the plurality of focusing elements are configured to converge light from the plurality of filter units.

[0045] In the embodiments of the present disclosure, the filter unit functions as a diverging element, diverging light from the corresponding light-emitting element in the light-emitting functional layer to increase the viewing angle. The light diverged by the filter unit is then converged by the condensing element to increase the brightness of each subpixel. Typically, the brightness and uniformity of light in the middle region of light emitted from the light-emitting element in the light-emitting functional layer toward each subpixel is relatively high, while the brightness and uniformity of light in the edge region are generally poor. In the embodiments of the present disclosure, the combination of the filter unit and the corresponding condensing element can fully utilize the light in the middle region. The light in the middle region emitted by each light-emitting element can be first diverged by the filter unit and then converged by the condensing element, which is advantageous for improving the display uniformity of the display panel. Meanwhile, the light in the edge region emitted by each light-emitting element, after being diverged by the filter element, is deflected by the light-absorbing element (e.g., black matrix) between adjacent filter elements and absorbed by the absorbed element, or is emitted at a large angle from the adjacent subpixel, thereby increasing the viewing angle.

[0046] Specific configurations of display panels in some embodiments of the present disclosure will be described in detail below with reference to FIGS.

[0047] 2 is a schematic illustration of an optical path diagram of a display panel 20 and a portion thereof in one or more embodiments of the present disclosure. As shown in FIG. 2, the display panel 20 may include a substrate 21, a light-emitting functional layer 22 disposed on the substrate 21, a filter layer 24 disposed on a side of the light-emitting functional layer 22 facing away from the substrate 21, and a plurality of light-collecting elements 26 disposed on a side of the filter layer 24 facing away from the substrate 21. The filter layer 24 may include a plurality of filter units 241. Each filter unit 241 may be designed to diverge at least a portion of light from the light-emitting functional layer 22. Each light-collecting element 26 among the plurality of light-collecting elements 26 may be configured to converge light from a corresponding filter unit 241.

[0048] In some embodiments of the present disclosure, the light-emitting functional layer 22 may include a plurality of light-emitting elements. Orthogonal projections of the plurality of light-emitting elements onto the substrate may overlap with orthogonal projections of the plurality of filter units 241 onto the substrate. In one or more embodiments of the present disclosure, orthogonal projections of the plurality of filter units 241 onto the substrate 21 overlap with orthogonal projections of the plurality of light-collecting elements 26 onto the substrate 21. That is, the plurality of filter units 241 correspond one-to-one to the plurality of light-collecting elements 26 and overlap in the thickness direction of the display panel 20. In an optional embodiment of the present disclosure, the orthogonal projections of the plurality of light-emitting elements onto the substrate, the orthogonal projections of the plurality of filter units 241 onto the substrate, and the orthogonal projections of the plurality of light-collecting elements 26 onto the substrate overlap.

[0049] Note that in some embodiments of the present disclosure, "each filter unit 241 may be designed to diverge at least a portion of light from the light-emitting functional layer 22" means that each filter unit 241 may be designed to diverge at least a portion of light from a light-emitting element corresponding to the filter unit in the light-emitting functional layer 22. For simplicity, in this specification, at least a portion of light from each light-emitting element corresponding to each filter unit in the light-emitting functional layer 22 will be collectively referred to as light from the light-emitting functional layer 22.

[0050] 2, each filter unit 241 can diverge light emitted from a corresponding light-emitting element in the light-emitting functional layer 22, thereby increasing the viewing angle of each sub-pixel, while uniformly dispersing light from a central region throughout the sub-pixel to improve brightness uniformity. The light-collecting element 26 can converge the diverged light through the filter unit 241 to increase the brightness of the entire display panel 20. Therefore, the display panel 20 according to the embodiment of the present disclosure can achieve a wide viewing angle without significantly reducing brightness.

[0051] In some embodiments of the present disclosure, the material of substrate 21 may be a semiconductor material such as monocrystalline silicon or polycrystalline silicon. In alternative embodiments, substrate 21 may be fabricated from other rigid or flexible materials such as glass, plastic, etc.

[0052] In some embodiments of the present disclosure, the light-emitting functional layer 22 may be a continuous film layer, and the light-emitting functional layer may be defined as a plurality of light-emitting elements used for a plurality of pixels through pixel-defining openings in the pixel-defining layer. The light-emitting functional layer 22 may include, for example, a hole-injection layer, a hole-transport layer, a light-emitting layer, an electron-transport layer, and an electron-injection layer, which are stacked in sequence.

[0053] In some embodiments of the present disclosure, the plurality of filter units 241 may include at least one first color filter unit, at least one second color filter unit, and at least one third color filter unit. For example, the at least one first color filter unit may include a red filter unit R, the at least one second color filter unit may include a green filter unit G, and the at least one third color filter unit may include a blue filter unit B. As shown in FIG. 2 , in some embodiments of the present disclosure, all of the plurality of filter units 241 may be designed to diverge at least a portion of light from the light-emitting functional layer such that the viewing angle of each pixel can be expanded by the divergence of light by the corresponding filter unit 241, thereby expanding the overall viewing angle of the display panel 20.

[0054] 2 , each filter unit 241 may include a first surface 241a facing the light-emitting functional layer and a second surface 241b facing away from the light-emitting functional layer. To use each filter unit 241 as a plano-concave lens, the second surface 241b of each filter unit 241 may be concave, and the first surface 241a may be flat. In an exemplary embodiment, the second surface 241b of each filter unit 241 may be a concave spherical surface with a radius of curvature of 1.6 μm to 2.4 μm. Configuring the second surface 241a of each filter unit 241 as a concave spherical surface is advantageous for process fabrication.

[0055] In an optional embodiment, the first surface 241a of the filter unit 241 can be a concave surface, and the second surface 241b of the filter unit 241 can be a flat surface. In another optional embodiment, the first surface 241a and the second surface 241b of the filter unit 241 can both be concave surfaces recessed toward the inside of the corresponding filter unit 241, allowing the filter unit 241 to function as a biconcave lens. In the embodiments of the present disclosure, a filter unit 241 having at least one concave surface can also be referred to as a concave filter unit, and a filter unit having both the first surface and the second surface flat can also be referred to as a flat filter unit.

[0056] In some embodiments of the present disclosure, the effect of the filter unit 241 on the light from the light-emitting functional layer 22 may be equivalent to the effect of light emission by a point light source. FIG. 3 schematically illustrates an equivalent optical path of the display panel of FIG. 2 in one or more embodiments of the present disclosure. In FIG. 3, only the equivalent optical path for one filter unit 241 is shown. As shown in FIG. 3, the light emitted by the filtered unit 241 may correspond to light emitted from a point light source located near the light-emitting functional layer 22. In the equivalent optical path illustrated in FIG. 3, the filter unit 241 may be equivalent to a point light source, and the light emitted from the equivalent point light source is directly incident on the condenser element 26 and converged by the condenser element 26.

[0057] In some embodiments of the present disclosure, adjacent filter units 241 among the plurality of filter units 241 may have a certain overlay. For example, the overlay may be 0±0.6 μm. In an exemplary embodiment, adjacent filter units 241 may be spaced apart via a black matrix 28 disposed between the adjacent filter units 241 to prevent color migration between adjacent pixels. In this case, adjacent filter units 241 may have no overlay or a negative overlay (as shown in FIG. 2 ), i.e., a gap may be present between the adjacent filter units and the black matrix 28 may be located in the gap. When a black matrix 28 is disposed between adjacent filter units 241, a certain overlay may be present between each filter unit 241 among the adjacent filter units 241 and the black matrix 28, i.e., a portion of each filter unit 241 may overlap and connect to the corresponding black matrix 28, thereby preventing light leakage. To further prevent light leakage, an overlay may be present between the portions of adjacent filter units 241 that are located on the black matrix 28.

[0058] In a small display panel (e.g., a micro display panel), the size of the black matrix needs to be set particularly small so as not to affect the aperture ratio of the display panel, and a small black matrix significantly increases the difficulty of the process. In an alternative embodiment, the black matrix 28 may not be provided between adjacent filter units 241, and different pixels may be spaced apart by overlapping the adjacent filter units 241, thus eliminating the step of forming a black matrix and simplifying the process.

[0059] In some embodiments of the present disclosure, the light-collecting element 26 may be a condensing lens. As shown in FIG. 2, the light-collecting lens 26 may be a plano-convex lens having a flat light-entrance surface facing the filter layer 24 and an arc-shaped light-exiting surface facing away from the filter layer 24. In some embodiments of the present disclosure, the radius of curvature of the arc-shaped light-exiting surface of the plano-convex lens is smaller than the radius of curvature of the concave spherical surface of the filter unit, so that the light is essentially converged after passing through the light-collecting lens 26 and the filter unit 241 sequentially. For example, the radius of curvature of the arc-shaped light-exiting surface of the plano-convex lens may be approximately 1.0 to 1.9 μm. In an optional embodiment, the light-collecting element 26 is a biconvex lens.

[0060] In some other embodiments of the present disclosure, the light-collecting element 26 may be a light-collecting prism, such as a prism, a rectangular prism, or an isosceles trapezoid prism. Those skilled in the art will understand that the light-collecting element 26 used in the display panel 20 of the embodiments of the present disclosure is not limited to those described in detail in the embodiments of the present disclosure, and any element or combination of elements that can have a converging effect on light can be applied to the present disclosure.

[0061] In some embodiments of the present disclosure, a gap may be provided between adjacent focusing elements 26 among the plurality of focusing elements 26 to prevent process errors during the manufacturing process from causing adhesion between the focusing elements. In an exemplary embodiment, the gap between adjacent focusing elements may be approximately 0.4 to 1.0 μm. In this manner, not only can adjacent focusing elements be prevented from being too close to each other during the manufacturing process, but also a gap that is too large can be avoided, resulting in light wastage. It is understood that the gap may be appropriately adjusted according to actual conditions to take into account brightness gain and brightness viewing angle.

[0062] In some embodiments of the present disclosure, after the light emitted from the light-emitting functional layer is diverged through each filter unit, the light located in the middle part enters the focusing element and is converged by the focusing element to increase the brightness, while the light located in the edge part does not enter the focusing element but can exit through the gap between adjacent focusing elements (as shown by the thick dotted arrows in Figures 2 and 3), thereby increasing the viewing angle range.

[0063] 2 , in some embodiments of the present disclosure, the display panel 20 may further include a transistor array 27 including a plurality of transistors located on the substrate 21, an encapsulation layer 23 located between the filter layer 24 and the light-emitting functional layer 22, and a planarization layer 25 located between the filter layer 24 and the plurality of light-collecting elements 26. The transistor array 27 may be located between the substrate 21 and the light-emitting functional layer 22.

[0064] The display panel 20 according to the embodiment of the present disclosure may further include other necessary components, such as a first electrode (e.g., an anode, also called a pixel electrode), a second electrode (e.g., a cathode, also called a common electrode), adhesive rubber located above the light-collecting elements 26, and other necessary components not shown in the drawings. The structure or configuration of these components may adopt any configuration known in the prior art, and will not be specifically described in the present disclosure.

[0065] In some embodiments of the present disclosure, the refractive index difference between the media located on both sides of the concave spherical surface of the filter unit 241 (e.g., the planarization layer and the filter element) is greater than the refractive index difference between the media located on both sides of the arc-shaped light output surface of the focusing element 26 (e.g., the plano-convex lens and the adhesive rubber 31), so that the light becomes essentially converged output light after passing through the focusing lens 26 and the filter unit 241 sequentially.

[0066] In some embodiments of the present disclosure, the refractive index of the filter layer 24 may be greater than the refractive indexes of the planarization layer 25 and the focusing elements 26. As an example, the refractive index of the filter layer 24 may be approximately 1.6 to 1.75, the refractive index of the focusing elements 26 may be approximately 1.56 to 1.60, and the refractive index of the planarization layer 25 may be approximately 1.44 to 1.55.

[0067] FIG. 4 is a schematic diagram illustrating a monochromatic viewing angle simulation of a concave filter unit and a planar filter unit according to one or more embodiments of the present disclosure. While the simulation was performed for a monochromatic color (e.g., red), it can be understood that a similar effect is achieved for a color (RGB) display panel. As shown in FIG. 4, the viewing angle range (shown by the dotted line) of the display panel with the planar filter unit is only approximately -18° to +18°, while the viewing angle range (shown by the solid line) of the display panel with the concave filter unit according to one or more embodiments of the present disclosure is increased to approximately -60° to +60°. Thus, the viewing angle of the display panel with the concave filter unit according to one or more embodiments of the present disclosure is significantly improved, without any significant decrease in brightness.

[0068] Among silicon-based OLED display panels, especially VR / AR display panels, users typically desire a display panel with a specific horizontal viewing angle range, i.e., a customized viewing angle range. For example, users may expect a good display effect within a specific viewing angle range of ±40° to ±60°. A display panel having a concave filter unit according to an embodiment of the present disclosure can also achieve this goal. As shown in FIG. 4, a display panel having a concave filter unit according to an embodiment of the present disclosure can achieve specific viewing angle ranges of approximately -60° to -35° and +35° to +60° because the brightness is higher within the ranges of approximately -60° to -35° and +35° to +60°. In optional embodiments, customization of other viewing angle ranges can be achieved by changing configuration parameters of components of a display panel according to an embodiment of the present disclosure (e.g., at least one of the radius of curvature of the concave spherical surface of the filter unit and the radius of curvature of the arc-shaped light-emitting surface of the light-collecting element).

[0069] In yet another alternative embodiment, the relative positions of the components of the display panel according to the embodiment of the present disclosure can be changed to achieve an offset of a particular viewing angle range. For example, the pixel electrodes (first electrodes) of the display panel can be offset leftward or rightward relative to the light-collecting elements in a direction parallel to the substrate, thereby offsetting the overall viewing angle of the display panel leftward or rightward.

[0070] FIG. 9 schematically illustrates the layout of a display panel with an offset viewing angle range and its optical path diagram. In the embodiment illustrated in FIG. 9, multiple first electrodes 29 and second electrodes 30 are shown, with the second electrode 30 located on the side of the first electrode 29 facing away from the substrate 21. As illustrated in FIG. 9, the orthogonal projection of the multiple first electrodes 29 onto the substrate 21 can partially overlap the orthogonal projection of the multiple light-collecting elements 26 onto the substrate 21. In this embodiment, the distance L between the center of each first electrode 29 and the center of the light-collecting element 26 that partially overlaps its orthogonal projection in a direction parallel to the substrate 21 is greater than 0. That is, the multiple first electrodes 29 can be translated in a direction parallel to the substrate 21, for example, to the right, relative to the multiple light-collecting elements 26. This corresponds to the filter unit 241 and the light-collecting element 26 being offset leftward relative to the entire corresponding first electrode 29, thereby offsetting the filter unit 241 and the light-collecting element 26 leftward relative to the corresponding light-emitting element in the light-emitting functional layer. Such a relative offset between the elements causes the viewing angle of the display panel to deviate from the normal viewing angle direction, for example, to be offset to the left as shown in FIG.

[0071] It can be understood that when the filter unit 241 and the light-collecting element 26 are offset to the right with respect to the first electrode 29, the viewing angle of the display panel is also offset to the right accordingly.

[0072] For ease of explanation and to avoid confusion, Fig. 9 does not show the transistor array 27 illustrated in other embodiments of the present disclosure, but this does not mean that the embodiment shown in Fig. 9 does not include the transistor array 27. In practice, the transistor array 27 can be located between the first electrode 29 and the substrate 21, and the first electrode 29 can be connected to the transistors of the transistor array 27 through via holes.

[0073] 5 is a schematic illustration of another display panel 60 and its optical path diagram according to one or more embodiments of the present disclosure. The display panel 60 shown in FIG. 5 shares some similarities with the display panel 20 shown in FIG. 2, and the description provided with respect to FIG. 2 applies to the display panel 60 shown in FIG. 5 as appropriate. Therefore, in the following description, only the differences from the embodiment shown in FIG. 2 will be described, and the same parts as those in the embodiment shown in FIG. 2 will be omitted.

[0074] The display panel 60 shown in FIG. 5 differs from the display panel 20 shown in FIG. 2 in the structure of the focusing element 26. As shown in FIG. 5, at least one focusing element 26 among the plurality of focusing elements may be a lens (also called a flat-top lens) surrounded by a first plane facing the filter layer 24, a second plane away from the filter layer 24, and two curved surfaces connecting the first and second planes. The two curved surfaces of the lens can converge incident light toward the second plane. In the embodiment shown in FIG. 3, the filter element 241 can diverge light from the light-emitting functional layer 22, and then the edge portions of the diverged light can be converged toward the middle of the flat-top lens by the two curved surfaces of the flat-top lens, thereby effectively utilizing the light at the edge portions and similarly improving the brightness of the display panel.

[0075] Although each of the multiple focusing elements shown in Figure 5 is designed as a flat-top lens, some of the multiple focusing elements (e.g., focusing elements corresponding to one or two color filter units among the red filter unit, green filter unit, and blue filter unit) may be designed as flat-top focusing elements, and the remaining focusing elements may be designed as plano-convex lenses or other types of lenses.

[0076] Figure 6 schematically illustrates yet another display panel 70 and its optical path diagram in accordance with one or more embodiments of the present disclosure. The display panel 70 illustrated in Figure 6 shares some similarities with the display panel 20 illustrated in Figure 2, and the description provided with respect to Figure 2 applies to the display panel illustrated in Figure 6 as appropriate. Therefore, in the following description, only the differences from the embodiment illustrated in Figure 2 will be described, and the same parts as those in the embodiment illustrated in Figure 2 will be omitted.

[0077] 6, the plurality of filter units 241 may include at least one first color filter unit, at least one second color filter unit, and at least one third color filter unit. For example, the at least one first color filter unit may include a red filter unit R, the at least one second color filter unit may include a green filter unit G, and the at least one third color filter unit may include a blue filter unit B. In the embodiment shown in FIG. 6, in order to meet the different color offset needs of different users' display panels, one of the red filter unit R, the green filter unit G, and the blue filter unit B may be designed to diverge at least a portion of the light from the light-emitting functional layer 22.

[0078] As an example, a user desiring an overall red bias for the display panel can design the top surface of the red filter unit R in the filter layer 24 as a concave sphere, and the top surfaces of the green filter unit G and the blue filter unit B as flat surfaces. The concave red filter unit R diverges incident light and deflects the edge portions of the diverged light (e.g., light incident on gaps between adjacent condensing elements 26) toward adjacent pixels, thereby achieving a red bias for the entire display panel. A user desiring an overall green bias for the display panel can design the top surface of the green filter unit G in the filter layer 24 as a concave sphere, and the top surfaces of the red filter unit R and the blue filter unit B as flat surfaces. The concave green filter unit G diverges incident light and deflects the edge portions of the diverged light (e.g., light incident on gaps between adjacent condensing elements 26) toward adjacent pixels, thereby achieving a green bias for the entire display panel. A user who desires an overall blue bias for the display panel can design the top surface of the blue filter unit B in the filter layer 24 as a concave sphere, and the top surfaces of the green filter unit G and the red filter unit R as flat surfaces. The concave blue filter unit B diverges incident light and deflects the edge portions of the diverged light (for example, light incident in the gaps between adjacent light-collecting elements 26) toward adjacent pixels, thereby making the entire display panel blue-biased.

[0079] It can be understood that in some embodiments of the present disclosure, two of the red, green, and blue filter units R, G, and B can be designed to diverge at least a portion of the light from the light-emitting functional layer to achieve a user's color adjustment needs for the display panel. FIG. 10 schematically illustrates another display panel 80 and its optical path diagram in one or more embodiments of the present disclosure. The display panel 80 illustrated in FIG. 10 shares some similarities with the display panel 20 illustrated in FIG. 2 , and the description provided with respect to FIG. 2 applies to the display panel illustrated in FIG. 10 as appropriate. Therefore, in the following description, only the differences from the embodiment illustrated in FIG. 2 will be described, and the same parts as those in the embodiment illustrated in FIG. 2 will be omitted.

[0080] 10 , the plurality of filter units 241 may include a red filter unit R, a green filter unit G, and a blue filter unit B. In the embodiment shown in FIG. 10 , in order to meet different color offset needs of different users' display panels, two of the red filter unit R, the green filter unit G, and the blue filter unit B may be designed to diverge at least a portion of the light from the light-emitting functional layer 22.

[0081] Display panels, especially silicon-based display panels, typically suffer from color bias, especially when viewed at a large viewing angle. For example, the display panel may exhibit a red bias. In some embodiments of the present disclosure, to improve the red bias of the display panel, the top surfaces of the green filter unit G and the blue filter unit B are designed as concave spherical surfaces, i.e., the green filter unit G and the blue filter unit B are configured as concave filter units, and the red filter unit R is configured as a flat filter unit. This configuration allows the large viewing angle of the green filter unit G and the blue filter unit B to improve the red bias of the display panel.

[0082] In an alternative embodiment, the red filter unit R and the blue filter unit B can be arranged as concave filter units, and the green filter unit G can be arranged as a flat filter unit, behind a green-biased display panel, so that the large viewing angle of the red filter unit R and the blue filter unit B can improve the green-biased phenomenon of the display panel.

[0083] In yet another alternative embodiment, the red and green filter units R and G can be arranged as concave filter units and the blue filter unit B as a flat filter unit behind a blue-biased display panel, which can improve the blue-bias phenomenon of the display panel due to the large viewing angle of the red and green filter units R and G.

[0084] Another aspect of the present disclosure further discloses a display device that may include a display panel according to the present disclosure, such as one or more of the display panels disclosed in detail above. Therefore, reference may be made to the display panel embodiments for select embodiments of the display device. FIG. 7 schematically illustrates a display device 800 according to one or more of the embodiments of the present disclosure. As shown in FIG. 7, the display device 800 may include one or more of the display panels 20, 60, 70, or 80 disclosed in detail herein. The display device 800 may further include a drive circuit 801 for providing drive signals to drive the display panel.

[0085] In yet another aspect of the present disclosure, a method for manufacturing a display panel is also disclosed. The method can be used to manufacture at least one display panel according to the present disclosure, such as one or more of the display panel embodiments disclosed in detail above. Therefore, reference can be made to the display panel embodiments for alternative embodiments of the method. The method can include the following steps, which can be performed in a predetermined order or in a different order. Additional method steps not listed can also be provided. Two or more method steps can be performed at least partially simultaneously, or all method steps can be performed simultaneously. Method steps can also be performed repeatedly two or more times.

[0086] 8 is a schematic flow chart of a method for manufacturing a display panel according to one or more embodiments of the present disclosure. As shown in FIG. 8, the method may include steps S91, S93, S95, and S97.

[0087] In step S91, a substrate 21 is provided. The material of the substrate 21 may be a semiconductor material such as monocrystalline silicon or polycrystalline silicon. In alternative embodiments, the substrate 21 may be made of other rigid or flexible materials such as glass, plastic, etc.

[0088] In step S93, the light-emitting functional layer 22 is formed on the substrate 21. The light-emitting functional layer 22 may include a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer, which are stacked in this order.

[0089] In step S95, a filter layer 24 is formed on the light-emitting functional layer 22, the filter layer 24 including a plurality of filter units 241, where at least one of the plurality of filter units 241 is designed to diverge at least a portion of light from the light-emitting functional layer 22. In an exemplary embodiment, each filter unit 241 may include a first surface facing the light-emitting functional layer 22 and a second surface facing away from the light-emitting functional layer 22. Here, the second surface of each filter unit 241 is concave to diverge the light from the light-emitting functional layer 22. In an optional embodiment, to achieve different color bias effects of the display panel, the second surfaces of some filter units (e.g., identical color filter units) among the plurality of filter units 241 may be concave, and the second surfaces of the remaining filter units 241 may be flat.

[0090] In step S97, a plurality of focusing elements 26 are formed on the filter layer 24, and the plurality of focusing elements 26 are configured to converge light from the plurality of filter units 241. In this step, since at least a portion of the surface of the filter unit 241 of the filter layer 24 is concave, it is possible to first form a planarization layer 25 on the filter layer 24, and then form the plurality of focusing elements 26 on the planarization layer 25.

[0091] The foregoing description of embodiments has been provided for purposes of illustration and description. It is not intended to be restrictive or limiting of the present disclosure. While each element or feature of a particular embodiment is generally not limited to a particular embodiment, where appropriate, these elements and features are interchangeable and may be used in selected embodiments without specific illustration or description. Likewise, the present disclosure may be modified in many ways. Such modifications should not be considered a departure from the present disclosure, and all such modifications are within the scope of the present disclosure.

[0092] There are various subdivisions of the features noted in connection with the above aspects of the present disclosure. Additional features may be incorporated into the above aspects of the present disclosure. These subdivisions and additional features may exist alone or in any combination. For example, the various features described above in connection with any exemplary embodiment of the present disclosure may be incorporated alone or in any combination into any of the above aspects of the present disclosure.

Claims

1. A display panel, A substrate; a light-emitting functional layer located on the substrate; a filter layer located on a side of the light-emitting functional layer that is farther from the substrate; a plurality of focusing elements located on a side of the filter layer away from the substrate, the filter layer includes a plurality of filter units, wherein at least one filter unit of the plurality of filter units is designed to diverge at least a portion of light from the light-emitting functional layer; The plurality of light-collecting elements are configured to converge light from the plurality of filter units.

2. Orthogonal projections of the plurality of filter units onto the substrate overlap with orthogonal projections of the plurality of light-collecting elements onto the substrate. The display panel according to claim 1 .

3. The plurality of filter units include at least one first color filter unit, at least one second color filter unit, and at least one third color filter unit, and at least one of the first color filter unit, the second color filter unit, and the third color filter unit is designed to diverge at least a portion of light from the light-emitting functional layer. The display panel according to claim 2 .

4. Only one of the first color filter unit, the second color filter unit, and the third color filter unit is designed to diverge at least a portion of the light from the light-emitting functional layer. The display panel according to claim 3 .

5. Two of the first color filter unit, the second color filter unit, and the third color filter unit are designed to diverge at least a portion of the light from the light-emitting functional layer. The display panel according to claim 3 .

6. The first color filter unit, the second color filter unit, and the third color filter unit are all designed to diverge at least a portion of the light from the light-emitting functional layer. The display panel according to claim 3 .

7. Each filter unit of the plurality of filter units includes a first surface facing the light-emitting functional layer and a second surface facing away from the light-emitting functional layer, and at least one of the first surface and the second surface of at least one filter unit designed to diverge at least a portion of light from the light-emitting functional layer is a concave surface. The display panel according to claim 1 .

8. the second surface of at least one filter unit designed to diverge at least a portion of the light from the light-emitting functional layer is concave and the first surface thereof is flat, and the first surface and the second surface of the remaining filter units other than the filter unit designed to diverge at least a portion of the light from the light-emitting functional layer are flat, The concave surface is a concave spherical surface, and the light-collecting element is a light-collecting lens or a light-collecting prism. The display panel according to claim 7 .

9. an overlay between adjacent filter units of the plurality of filter units; The display panel according to claim 1 .

10. The condenser lens is a plano-convex lens including a flat light entrance surface facing the filter layer and an arc-shaped light exit surface facing away from the filter layer. The display panel according to claim 8 .

11. a radius of curvature of the concave spherical surface is larger than a radius of curvature of the arc-shaped light exit surface of the plano-convex lens; The radius of curvature of the concave spherical surface is 1.6 to 2.4 μm, and the radius of curvature of the arc-shaped light exit surface of the plano-convex lens is 1.0 to 1.9 μm. The display panel according to claim 10.

12. The refractive index difference between the media located on both sides of the concave spherical surface is greater than the refractive index difference between the media located on both sides of the arc-shaped light exit surface of the plano-convex lens. The display panel according to claim 10.

13. The plurality of light-collecting elements have gaps between adjacent light-collecting elements. The display panel according to claim 8 .

14. The display panel further comprises: a planarization layer positioned between the filter layer and the plurality of light-collecting elements; The display panel according to claim 12.

15. The refractive index of the filter layer is greater than the refractive index of the planarizing layer and the refractive index of the light-collecting element. The display panel according to claim 14.

16. The display panel further comprises: a plurality of first electrodes and a plurality of second electrodes insulated from each other and positioned between the substrate and the filter layer, wherein the second electrode is positioned on a side of the plurality of first electrodes that is away from the substrate; The display panel according to claim 1 .

17. Orthogonal projections of the plurality of first electrodes onto the substrate partially overlap with orthogonal projections of the plurality of light-collecting elements onto the substrate, and the distance between the center of each first electrode and the center of the light-collecting element partially overlapping with the orthogonal projection in a direction parallel to the substrate is greater than 0. The display panel according to claim 16.

18. A display device comprising the display panel according to any one of claims 1 to 17.

19. Providing a substrate; forming a light-emitting functional layer on the substrate; forming a filter layer on the light-emitting functional layer; forming a plurality of light-collecting elements on the filter layer; the filter layer includes a plurality of filter units, wherein at least one filter unit of the plurality of filter units is designed to diverge at least a portion of light from the light-emitting functional layer; The method for manufacturing a display panel according to claim 1 , wherein the plurality of light-collecting elements are configured to converge light from the plurality of filter units.

20. forming a plurality of light-collecting elements on the filter layer, forming a planarization layer on the filter layer; and forming a plurality of light-collecting elements on the planarization layer.

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