Display substrate and manufacturing method therefor, and display device

Abstract

A display substrate and a manufacturing method therefor, and a display device, relating to the technical filed of display. The display substrate comprises: a light-emitting substrate (11), comprising a light-emitting area (AA), the light-emitting area comprising a plurality of sub-light-emitting areas (EA); a packaging layer (12), arranged on the light exit side of the light-emitting substrate, the surface of the packaging layer facing away from the light-emitting substrate comprising a plurality of recessed areas (AX), the recessed areas being recessed towards the side close to the light-emitting substrate, the packaging layer comprising a plurality of sub-packaging layers (14) that are stacked, and the recessed areas comprising openings of the plurality of sub-packaging layers; and a micro-lens array (13), located on the side of the packing layer facing away from the light-emitting substrate, the micro-lens array comprising a plurality of micro-lenses (ML), the micro-lenses being located in the recessed areas, and the orthographic projections of the micro-lenses on the light-emitting substrate at least partially overlapping the sub-light-emitting areas so as to change the propagation direction of at least part of emitted light of the sub-light-emitting areas.

Description

Display substrate and its preparation method, display device

[0001] Cross-reference to related applications

[0002] This disclosure claims priority to Chinese Patent Application No. 202410704144.9, filed on May 31, 2024, entitled “Display substrate and method for preparation thereof, display device”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of display technology, and in particular to a display substrate, a method for preparing the same, and a display device. Background Technology

[0004] Silicon-based organic light-emitting diode (OLED) displays have attracted widespread attention due to their advantages such as high resolution, low power consumption, small size, and light weight. Silicon-based OLEDs show great promise for applications in high-resolution near-eye displays, including wearable devices, industrial security, and medical applications.

[0005] Overview

[0006] This disclosure provides a display substrate, including:

[0007] A light-emitting substrate includes a light-emitting region, wherein the light-emitting region includes a plurality of sub-light-emitting regions;

[0008] An encapsulation layer is disposed on the light-emitting side of the light-emitting substrate. The surface of the encapsulation layer facing away from the light-emitting substrate includes multiple recessed areas, which are recessed towards the side closest to the light-emitting substrate. The encapsulation layer includes multiple sub-encapsulation layers stacked together, and the multiple recessed areas include openings in the multiple sub-encapsulation layers.

[0009] A microlens array is located on the side of the encapsulation layer opposite to the encapsulation layer. The microlens array includes multiple microlenses located within multiple recessed areas. The orthographic projections of the multiple microlenses on the light-emitting substrate at least partially overlap with the multiple sub-light-emitting areas to change the propagation direction of at least part of the emitted light from the multiple sub-light-emitting areas.

[0010] In some embodiments, the plurality of microlenses includes:

[0011] In the orthographic projection onto the light-emitting substrate, the edge microlens is located on the side of the central microlens away from the center of the light-emitting area, and the principal ray angle of the edge microlens is greater than or equal to the principal ray angle of the central microlens.

[0012] In some embodiments, the principal ray angle of the plurality of microlenses gradually increases along the direction from the center of the light-emitting area to the edge of the light-emitting area.

[0013] In some embodiments, the microlens includes an interconnected dimming surface and a bottom surface. The dimming surface is disposed close to the encapsulation layer, and the bottom surface is disposed away from the encapsulation layer. The dimming surface includes a dimming position, and the distance between the dimming position and the bottom surface is greater than the distance between a non-dimming position and the bottom surface. In a projected image onto the light-emitting substrate, the distance between the dimming position and the center of the bottom surface is a first distance.

[0014] The plurality of microlenses includes a central microlens and edge microlenses. In the orthographic projection on the light-emitting substrate, the edge microlenses are located on the side of the central microlens away from the center of the light-emitting area, and the first distance of the edge microlenses is greater than or equal to the first distance of the central microlens.

[0015] In some embodiments, in the orthographic projection on the light-emitting substrate, the dimming position of the central microlens coincides with the center of the bottom surface of the central microlens, and the dimming position of the edge microlens is offset from the center of the bottom surface of the edge microlens.

[0016] In some embodiments, in the orthographic projection on the light-emitting substrate, the dimming position of the edge microlens is located on the side of the bottom surface of the edge microlens away from the center of the light-emitting area.

[0017] In some embodiments, in the orthographic projection on the light-emitting substrate, the dimming position of the edge microlens is located on the side of the bottom center of the edge microlens near the center of the light-emitting area.

[0018] In some embodiments, the plurality of said edge microlenses include:

[0019] In the orthographic projection onto the light-emitting substrate, the second edge microlens is located on the side of the first edge microlens away from the center of the light-emitting area, and the first distance of the second edge microlens is greater than or equal to the first distance of the first edge microlens.

[0020] In some embodiments, the distance between the dimming position and the bottom surface is a second distance, the second distance of the edge microlens is greater than or equal to the second distance of the central microlens, and the second distance of the second edge microlens is greater than or equal to the second distance of the first edge microlens.

[0021] In some embodiments, the plurality of edge microlenses include a third edge microlens and a fourth edge microlens. In the orthographic projection on the light-emitting substrate, the distance between the third edge microlens and the center of the light-emitting area is approximately equal to the distance between the fourth edge microlens and the center of the light-emitting area. The sub-light-emitting area that overlaps with the third edge microlens is the third sub-light-emitting area, and the sub-light-emitting area that overlaps with the fourth edge microlens is the fourth sub-light-emitting area. The third sub-light-emitting area and the fourth sub-light-emitting area are used to emit light of the same color.

[0022] The first distance of the third edge microlens is approximately equal to the first distance of the fourth edge microlens;

[0023] In the orthographic projection onto the light-emitting substrate, the distance between the dimming position of the third edge microlens and the center of the light-emitting area is approximately equal to the distance between the dimming position of the fourth edge microlens and the center of the light-emitting area; the distance between the center of the bottom surface of the third edge microlens and the center of the light-emitting area is approximately equal to the distance between the center of the bottom surface of the fourth edge microlens and the center of the light-emitting area; and the bottom surface dimension of the third edge microlens is approximately equal to the bottom surface dimension of the fourth edge microlens.

[0024] The distance between the dimming position of the third edge microlens and the bottom surface of the third edge microlens is approximately equal to the distance between the dimming position of the fourth edge microlens and the bottom surface of the fourth edge microlens.

[0025] In some embodiments, the plurality of edge microlenses include a fifth edge microlens and a sixth edge microlens. In the orthographic projection on the light-emitting substrate, the distance between the fifth edge microlens and the center of the light-emitting area is approximately equal to the distance between the fifth edge microlens and the center of the light-emitting area. The sub-light-emitting area that overlaps with the fifth edge microlens is the fifth sub-light-emitting area, and the sub-light-emitting area that overlaps with the sixth edge microlens is the sixth sub-light-emitting area. The fifth sub-light-emitting area and the sixth sub-light-emitting area are used to emit light of different colors.

[0026] The first distance of the fifth edge microlens is not equal to the first distance of the sixth edge microlens; and / or,

[0027] In the orthographic projection onto the light-emitting substrate, the distance between the dimming position of the fifth edge microlens and the center of the light-emitting area is not equal to the distance between the dimming position of the sixth edge microlens and the center of the light-emitting area, and / or, the distance between the center of the bottom surface of the fifth edge microlens and the center of the light-emitting area is not equal to the distance between the center of the bottom surface of the sixth edge microlens and the center of the light-emitting area, and / or, the bottom surface dimension of the fifth edge microlens is not equal to the bottom surface dimension of the sixth edge microlens; and / or,

[0028] The distance between the dimming position of the fifth edge microlens and the bottom surface of the fifth edge microlens is not equal to the distance between the dimming position of the sixth edge microlens and the bottom surface of the sixth edge microlens.

[0029] In some embodiments, the display substrate includes a plurality of encapsulation layers and a plurality of microlens arrays. The plurality of encapsulation layers include a first encapsulation layer and a second encapsulation layer. The plurality of microlens arrays include a first microlens array and a second microlens array. The first encapsulation layer, the first microlens array, the second encapsulation layer, and the second microlens array are stacked sequentially. The first encapsulation layer is disposed close to the light-emitting substrate.

[0030] In the first microlens array, the first distance between the edge microlenses is equal to the first distance between the central microlens; and

[0031] In the second microlens array, the first distance of the edge microlens is greater than the first distance of the central microlens.

[0032] In some embodiments, the bottom surface is a plane, and the dimming surface includes at least one of the following: a portion of a sphere, a portion of an ellipsoid, a Fresnel surface, and a freeform surface.

[0033] In some embodiments, the plurality of microlenses are made of resin material that can transmit multiple colors of visible light, and the gap between two adjacent microlenses is greater than or equal to 0 and smaller than the gap between two adjacent sub-light-emitting regions.

[0034] In some embodiments, the display substrate further includes:

[0035] A color resist layer, located between the light-emitting substrate and the encapsulation layer, includes multiple color resist patterns. The orthographic projection of the multiple color resist patterns on the light-emitting substrate covers the multiple sub-light-emitting areas, and is used to transmit a single color of visible light. The edges of two adjacent color resist patterns overlap each other.

[0036] In some embodiments, the material of the plurality of microlenses includes a color resist material for transmitting a single color of visible light, and the edges of two adjacent microlenses overlap each other.

[0037] In some embodiments, the plurality of microlenses includes at least one of the following:

[0038] A red microlens, comprising a red color resist material, is used to transmit red light. In the orthogonal projection on the light-emitting substrate, the sub-light-emitting area overlapping with the red microlens is used to emit red light.

[0039] A green microlens, comprising a green color resist material, for transmitting green light; and a sub-light-emitting region overlapping with the green microlens in a projected image on the light-emitting substrate, for emitting green light; and

[0040] The blue microlens, comprising a blue color resist material, is used to transmit blue light. In the orthogonal projection onto the light-emitting substrate, the sub-light-emitting area overlapping with the blue microlens is used to emit blue light.

[0041] In some embodiments, each of the plurality of sub-encapsulation layers is an inorganic sub-encapsulation layer or an organic sub-encapsulation layer. The encapsulation layer includes the inorganic sub-encapsulation layer and the organic sub-encapsulation layer arranged alternately in sequence. The sub-encapsulation layer disposed close to the light-emitting substrate is the inorganic sub-encapsulation layer, and the sub-encapsulation layer disposed away from the light-emitting substrate is either the inorganic sub-encapsulation layer or the organic sub-encapsulation layer. The inorganic sub-encapsulation layer includes inorganic materials, and the organic sub-encapsulation layer includes organic materials.

[0042] In some embodiments, at least one of the microlenses in the microlens array is a tilted microlens, wherein the principal ray angle of the tilted microlens is greater than 0°, and the principal ray angle is the angle between the principal ray of the microlens and the normal direction of the light-emitting substrate.

[0043] In some embodiments, in the first microlens array, the second distance of the edge microlenses is equal to the second distance of the central microlens; and

[0044] In the second microlens array, the second distance of the edge microlenses is greater than the second distance of the central microlens.

[0045] In some embodiments, the display substrate further includes a leveling layer located on the side of the microlens array facing away from the light-emitting substrate, wherein the surface of the leveling layer facing away from the light-emitting substrate is planar, and the material of the leveling layer is the same as the material of the plurality of microlenses.

[0046] In some embodiments, the light-emitting substrate includes a substrate and a light-emitting device disposed on one side of the substrate.

[0047] In some embodiments, the light-emitting substrate further includes a pre-encapsulation layer disposed on the side of the light-emitting device facing away from the substrate.

[0048] In some embodiments, the light-emitting device is an OLED, which includes a first electrode, a light-emitting layer and a second electrode stacked together, wherein the first electrode is disposed close to the substrate.

[0049] In some embodiments, the light-emitting substrate further includes: a pixel defining layer for forming a plurality of openings, the light-emitting device being located within the plurality of openings, the first electrode being located between the pixel defining layer and the substrate, and the light-emitting layer and the second electrode being located on the side of the pixel defining layer opposite to the substrate.

[0050] In some embodiments, the light-emitting substrate 11 further includes: a metal electrode located between the substrate and the first electrode, connected to the substrate through a tungsten hole, and overlapped with the first electrode through a via.

[0051] This disclosure provides a display device including a display substrate as described in any embodiment.

[0052] This disclosure provides a method for fabricating a display substrate, including:

[0053] A light-emitting substrate is provided, the light-emitting substrate including a light-emitting region, the light-emitting region including a plurality of sub-light-emitting regions;

[0054] An encapsulation layer is formed on the light-emitting side of the light-emitting substrate. The surface of the encapsulation layer facing away from the light-emitting substrate includes multiple recessed areas, which are recessed towards the side closest to the light-emitting substrate. The encapsulation layer includes multiple sub-encapsulation layers stacked together, and the multiple recessed areas include openings in the multiple sub-encapsulation layers.

[0055] A microlens array is formed on the side of the encapsulation layer away from the encapsulation layer. The microlens array includes multiple microlenses located in multiple recessed areas. The orthogonal projection of the multiple microlenses on the light-emitting substrate at least partially overlaps with the multiple sub-light-emitting areas to change the propagation direction of at least part of the emitted light from the multiple sub-light-emitting areas.

[0056] In some embodiments, the step of forming an encapsulation layer on the light-emitting side of the light-emitting substrate includes:

[0057] An encapsulation film is formed on the light-emitting side of the light-emitting substrate; and

[0058] Using a grayscale mask, the encapsulation film is exposed, developed, and etched to obtain the encapsulation layer; and

[0059] The step of forming a microlens array on the side of the encapsulation layer opposite to the encapsulation layer includes:

[0060] An adhesive layer is formed by applying adhesive to the side of the encapsulation layer opposite to the light-emitting substrate. The adhesive layer is planar on the surface opposite to the light-emitting substrate and protrudes from the plurality of recessed areas.

[0061] The adhesive layer in the non-light-emitting area is removed to obtain the microlens array. The adhesive layer located in the plurality of recessed areas constitutes the plurality of microlenses of the microlens array.

[0062] In some embodiments, the light-emitting substrate includes a substrate, a light-emitting device, and a pre-encapsulation layer stacked sequentially.

[0063] The step of forming an encapsulation layer on the light-emitting side of the light-emitting substrate includes:

[0064] Using a grayscale mask, the pre-encapsulation layer is exposed, developed, and etched to obtain the encapsulation layer; and

[0065] The step of forming a microlens array on the side of the encapsulation layer opposite to the encapsulation layer includes:

[0066] A color resist material is coated on the side of the encapsulation layer away from the light-emitting substrate to form a color resist film. The surface of the color resist film away from the light-emitting substrate is planar and has protruding recessed areas. Then, the color resist film in the non-light-emitting area is removed to obtain the microlens array.

[0067] In some embodiments, the adhesive layer in the non-light-emitting area is removed using an exposure and development process.

[0068] In some embodiments, prior to the step of forming an encapsulation film on the light-emitting side of the light-emitting substrate, the method includes:

[0069] A color resist layer is prepared on the light-emitting side of the light-emitting substrate; and

[0070] The encapsulation film is formed on the side of the color resist layer opposite to the light-emitting substrate.

[0071] This disclosure provides a method for fabricating a display substrate, including:

[0072] Provide light-emitting substrates;

[0073] A color resist layer is prepared on the light-emitting side of the light-emitting substrate;

[0074] A first encapsulation film is formed on the side of the color resist layer away from the light-emitting substrate. Then, a grayscale mask is used to expose, develop and etch the first encapsulation film to obtain a first encapsulation layer. The surface of the first encapsulation layer away from the light-emitting substrate includes multiple recessed areas, which are recessed toward the side closer to the light-emitting substrate.

[0075] A first adhesive layer is formed by applying adhesive to the side of the first encapsulation layer away from the light-emitting substrate. The surface of the first adhesive layer away from the light-emitting substrate is planar and protrudes from the plurality of recessed areas. Then, the first adhesive layer in the non-light-emitting area is removed to obtain a first microlens array. The adhesive layer located in the plurality of recessed areas constitutes a plurality of microlenses in the first microlens array.

[0076] A second encapsulation film is formed on the side of the first microlens array facing away from the light-emitting substrate. Then, a grayscale mask is used to expose, develop, and etch the second encapsulation film to obtain a second encapsulation layer. The surface of the second encapsulation layer facing away from the light-emitting substrate includes multiple recessed areas, which are recessed towards the side closest to the light-emitting substrate.

[0077] A second adhesive layer is formed by applying adhesive to the side of the second encapsulation layer away from the light-emitting substrate. The surface of the second adhesive layer away from the light-emitting substrate is planar and protrudes from the plurality of recessed areas. Then, the second adhesive layer in the non-light-emitting area is removed to obtain a second microlens array. The adhesive layer located in the plurality of recessed areas constitutes a plurality of microlenses in the second microlens array.

[0078] The above description is merely an overview of the technical solution disclosed herein. In order to better understand the technical means of this disclosure and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this disclosure more apparent and understandable, specific embodiments of this disclosure are described below.

[0079] Brief description of the attached diagram

[0080] To more clearly illustrate the technical solutions in the embodiments or related technologies of this disclosure, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0081] It should be noted that the scale in the attached diagram is for illustrative purposes only and does not represent the actual scale.

[0082] Figure 1 shows a schematic cross-sectional view of the first type of display substrate;

[0083] Figure 2 illustrates a cross-sectional structural schematic diagram of the second type of display substrate;

[0084] Figure 3 illustrates a cross-sectional structural diagram of the third type of display substrate;

[0085] Figure 4 shows the curve of the principal ray angle of the microlens as a function of the half-image height;

[0086] Figure 5 illustrates a schematic cross-sectional structure of three display substrates;

[0087] Figure 6 illustrates a cross-sectional structure diagram of three other display substrates;

[0088] Figure 7 illustrates a cross-sectional structural diagram of three more display substrates;

[0089] Figure 8 illustrates a cross-sectional structural schematic diagram of yet another display substrate;

[0090] Figure 9 illustrates a schematic cross-sectional structure of a display substrate;

[0091] Figure 10 illustrates an exemplary planar structure diagram of a display device; and

[0092] Figure 11 illustrates a flowchart of a method for fabricating a display substrate.

[0093] Detailed description

[0094] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0095] In related technologies, microlenses are generally fabricated on a flat surface of a substrate using a thermal reflow curing process. However, due to the low controllability of the thermal reflow curing process, the resulting microlenses have poor uniformity and are difficult to fabricate.

[0096] To address the aforementioned problems, this disclosure provides a display substrate, as shown in FIG1 or FIG2. The display substrate includes: a light-emitting substrate 11, including a light-emitting region AA, the light-emitting region AA including a plurality of sub-light-emitting regions EA; an encapsulation layer 12 disposed on the light-emitting side of the light-emitting substrate 11, the surface of the encapsulation layer 12 away from the light-emitting substrate 11 including a plurality of recessed regions AX, the plurality of recessed regions AX being recessed toward the side closer to the light-emitting substrate 11, the encapsulation layer 12 including a plurality of sub-encapsulation layers 14 stacked together, the plurality of recessed regions AX including openings of the plurality of sub-encapsulation layers 14; and a microlens array 13 located on the side of the encapsulation layer 12 away from the encapsulation layer 12, the microlens array 13 including a plurality of microlenses ML, the plurality of microlenses ML being located within the plurality of recessed regions AX, the orthographic projection of the plurality of microlenses ML on the light-emitting substrate 11 at least partially overlapping with the plurality of sub-light-emitting regions EA, so as to change the propagation direction of at least part of the emitted light from the plurality of sub-light-emitting regions EA.

[0097] For example, as shown in FIG1 or FIG2, the encapsulation layer 12 may include two sub-encapsulation layers 14, three sub-encapsulation layers 14, four sub-encapsulation layers 14, five sub-encapsulation layers 14 or more sub-encapsulation layers 14.

[0098] For example, as shown in FIG1 or FIG2, the encapsulation layer 12 includes three sub-encapsulation layers 14, namely a first sub-encapsulation layer 141, a second sub-encapsulation layer 142 and a third sub-encapsulation layer 143 stacked in sequence, with the first sub-encapsulation layer 141 disposed close to the light-emitting substrate 11.

[0099] For example, as shown in FIG1 or FIG2, the recessed region AX includes an opening provided on a first sub-encapsulation layer 141, an opening provided on a second sub-encapsulation layer 142, and an opening provided on a third sub-encapsulation layer 143. The opening on the first sub-encapsulation layer 141 completely penetrates the first sub-encapsulation layer 141, the opening on the second sub-encapsulation layer 142 completely penetrates the second sub-encapsulation layer 142, and the opening on the third sub-encapsulation layer 143 partially penetrates the third sub-encapsulation layer 143.

[0100] For example, the sub-encapsulation layer 14 can be an inorganic sub-encapsulation layer or an organic sub-encapsulation layer. The encapsulation layer 12 includes, for example, inorganic and organic sub-encapsulation layers arranged alternately in sequence. The sub-encapsulation layer 14 disposed near the light-emitting substrate 11 is an inorganic sub-encapsulation layer, and the sub-encapsulation layer 14 disposed away from the light-emitting substrate 11 can be either an inorganic or organic sub-encapsulation layer. The inorganic sub-encapsulation layer includes, for example, inorganic materials such as silicon dioxide, silicon nitride, and silicon oxynitride. The organic sub-encapsulation layer includes, for example, organic materials.

[0101] For example, the first sub-encapsulation layer 141 is an inorganic sub-encapsulation layer, the second sub-encapsulation layer 142 is an organic sub-encapsulation layer, and the third sub-encapsulation layer 143 is an inorganic sub-encapsulation layer.

[0102] For example, the light-emitting area AA includes multiple sub-pixels, the multiple sub-light-emitting areas EA are located in different sub-pixels, the orthographic projections of multiple recessed areas AX on the light-emitting substrate 11 are located in different sub-pixels, and the orthographic projections of multiple microlenses ML on the light-emitting substrate 11 are located in different sub-pixels.

[0103] For example, a flat encapsulation film can be formed first on the light-emitting side of the light-emitting substrate 11. Then, a grayscale mask can be used to sequentially expose, develop, and etch the surface of the encapsulation film to form an encapsulation layer 12 with a recessed region AX on its surface. Since the recessed region AX on the surface of the encapsulation layer 12 can be formed using an easily controllable patterning process, a highly uniform recessed region AX can be prepared, and recessed regions AX of various shapes can be prepared.

[0104] In practice, various processes can be used to form the microlens ML within the pre-formed recessed area AX. For example, adhesive can be applied over the encapsulation layer 12, filling the recessed area AX, and curing will form the microlens ML. That is, the shape of the microlens ML is primarily determined by the shape of the pre-formed recessed area AX.

[0105] The display substrate provided in this disclosure has a microlens ML located in a recessed region AX pre-formed on the surface of the encapsulation layer 12, and the recessed region AX has high uniformity. Therefore, this disclosure can prepare a microlens ML with high uniformity, and can fabricate microlenses ML of various shapes. The process is simple and easy to control.

[0106] For example, as shown in FIG1 or FIG2, the orthogonal projection of the microlens ML on the light-emitting substrate 11 covers the sub-light-emitting area EA.

[0107] For example, the microlens ML can be a convex lens, a concave lens, or a Fresnel lens, etc.

[0108] For example, as shown in FIG1 or FIG2, at least one microlens ML in the microlens array 13 is a tilted microlens, and the principal ray angle CRA of the tilted microlens is greater than 0°. The principal ray angle CRA is the angle between the principal ray of the microlens ML (such as the viewing ray with the highest brightness) and the normal direction of the light-emitting substrate 11.

[0109] For example, as shown in FIG1 or FIG2, the plurality of microlenses ML include: a central microlens MLC and an edge microlens MLS. In the orthographic projection on the light-emitting substrate 11, the edge microlens MLS is located on the side of the central microlens MLC away from the center O of the light-emitting area, and the principal ray angle CRA of the edge microlens MLS is greater than or equal to the principal ray angle CRA of the central microlens MLC.

[0110] For example, the microlens array 13 includes one or more central microlenses MLC and one or more edge microlenses MLS.

[0111] As shown in Figure 1 or Figure 2, the distance between the orthographic projection of the central microlens MLC on the light-emitting substrate 11 and the center O of the light-emitting area is smaller than the distance between the orthographic projection of the edge microlens MLS on the light-emitting substrate 11 and the center O of the light-emitting area.

[0112] For example, as shown in FIG1 or FIG2, in the orthographic projection on the light-emitting substrate 11, the central microlens MLC is a microlens ML disposed near the center O of the light-emitting area, and the edge microlens MLS is a microlens ML disposed away from the center O of the light-emitting area.

[0113] For example, as shown in FIG1 or FIG2, the orthogonal projection of the central microlens MLC on the light-emitting substrate 11 covers the center O of the light-emitting area.

[0114] For example, as shown in Figure 4, the principal ray angle CRA of the central microlens MLC is 0°, while the principal ray angle CRA of the edge microlens MLS is greater than 0°. Thus, the central microlens MLC is used to positively converge the light emitted from the sub-emitting region EA near the center O of the emitting region, thereby improving the positive light output brightness. The edge microlens MLS is used to obliquely converge the light emitted from the sub-emitting region EA far from the center O of the emitting region, thereby improving the oblique light output brightness.

[0115] For example, as shown in Figure 4, the principal ray angle CRA of the multiple microlenses ML gradually increases along the direction from the center O of the light-emitting area to the edge of the light-emitting area AA. In Figure 4, the principal ray angle CRA of the microlenses ML increases from 0° to 16° from the center O of the light-emitting area to the edge of the light-emitting area AA.

[0116] Figure 4 shows the change of the principal ray angle CRA of the microlens with the half image height, which is the distance from any point AA in the luminous area to the center O of the luminous area. As shown in Figure 4, the principal ray angle CRA gradually increases with the increase of the half image height.

[0117] As shown in Figure 4, when the principal ray angle CRA of the microlens is consistent with the principal ray angle CRA of the optomechanical system or the whole machine, the microlens array 13 is adapted to the optomechanical system or the whole machine, which is beneficial to increasing the field of view of the whole machine.

[0118] As shown in Figure 1 or Figure 2, the microlens ML includes an interconnected dimming surface S1 and a bottom surface S2. The dimming surface S1 is positioned close to and facing the encapsulation layer 12, while the bottom surface S2 is positioned away from the encapsulation layer 12. The dimming surface S1 includes a dimming position B, and the distance between the dimming position B and the bottom surface S2 is greater than the distance between the non-dimming position and the bottom surface S2. The non-dimming position refers to any other position on the dimming surface S1 besides the dimming position B.

[0119] For example, as shown in Figure 1 or Figure 2, the bottom surface S2 is a plane. The geometric center of the bottom surface S2 is the bottom center A.

[0120] For example, the dimming surface S1 includes at least one of the following: a portion of a sphere (the dimming surface S1 of the central microlens MLC as shown in Figure 1 or Figure 2), a portion of an ellipsoid (the dimming surface S1 of the edge microlens MLS as shown in Figure 1 or Figure 2), a Fresnel surface (the dimming surface S1 of the microlens ML as shown in Figure 3), and a freeform surface.

[0121] It should be noted that, as shown in Figure 3, when the dimming surface S1 is a Fresnel surface, the dimming surface S1 with the Fresnel surface shape includes a central surface 31 and a sawtooth surface 32 surrounding the central surface 31. The dimming position B is located on the central surface 31, and the distance between the dimming position B and the bottom surface S2 is greater than the distance between the non-dimming position B on the central surface 31 and the bottom surface S2.

[0122] As shown in Figure 1 or Figure 2, in the orthographic projection on the light-emitting substrate 11, the distance between the dimming position B and the center A of the bottom surface is the first distance D1.

[0123] For example, as shown in Figure 1 or Figure 2, the first distance D1 of the edge microlens MLS is greater than or equal to the first distance D1 of the central microlens MLC.

[0124] In this way, the principal ray angle CRA of the peripheral microlens MLS can be greater than or equal to the principal ray angle CRA of the central microlens MLC. When the first distance D1 of the peripheral microlens MLS is equal to the first distance D1 of the central microlens MLC, the principal ray angle CRA of the peripheral microlens MLS is equal to the principal ray angle CRA of the central microlens MLC. When the first distance D1 of the peripheral microlens MLS is greater than the first distance D1 of the central microlens MLC, the principal ray angle CRA of the peripheral microlens MLS is greater than the principal ray angle CRA of the central microlens MLC.

[0125] For example, as shown in Figure 1 or Figure 2, in the orthographic projection on the light-emitting substrate 11, the dimming position B of the central microlens MLC coincides with the center A of the bottom surface of the central microlens MLC. In this way, the principal ray angle CRA of the central microlens MLC is 0°.

[0126] When the first distance D1 of the edge microlens MLS is greater than the first distance D1 of the central microlens MLC, as shown in Figure 1 or Figure 2, the dimming position B of the edge microlens MLS is offset from the center A of the bottom surface of the edge microlens MLS. In this way, the principal ray angle CRA of the central microlens MLC is greater than 0°.

[0127] To achieve the outward-expanding main ray angle (CRA) design, for example, as shown in FIG1, in the orthographic projection on the light-emitting substrate 11, the dimming position B of the edge microlens MLS is located on the side away from the center O of the light-emitting area from the bottom center A of the edge microlens MLS.

[0128] For example, as shown in FIG1, for all edge microlenses MLS in the same microlens array 13, the dimming position B is located on the side of the bottom center A away from the center O of the light-emitting area.

[0129] As shown in Figure 1, the edge microlens MLS located to the left of the center O of the light-emitting area has its dimming position B located to the left of the center A of its bottom surface. The edge microlens MLS located to the right of the center O of the light-emitting area has its dimming position B located to the right of the center A of its bottom surface. In this way, the principal ray angle of the edge microlens MLS located to the left of the center O of the light-emitting area is tilted to the left, and the principal ray angle of the edge microlens MLS located to the right of the center O of the light-emitting area is tilted to the right, thereby realizing the outward expansion type principal ray angle CRA design.

[0130] To achieve the cohesive master ray angle (CRA) design, for example, as shown in FIG2, in the orthographic projection on the light-emitting substrate 11, the dimming position B of the edge microlens MLS is located on the side of the bottom center A of the edge microlens MLS near the center O of the light-emitting area.

[0131] For example, as shown in Figure 2, for all edge microlenses (MLS) in the same microlens array 13, the dimming position B is located on the side of the bottom center A close to the center O of the light-emitting area.

[0132] As shown in Figure 2, the edge microlens MLS located to the left of the center O of the light-emitting area has its dimming position B located to the right of the center A of its bottom surface. The edge microlens MLS located to the right of the center O of the light-emitting area has its dimming position B located to the left of the center A of its bottom surface. In this way, the principal ray angle of the edge microlens MLS located to the left of the center O of the light-emitting area is tilted to the right, and the principal ray angle of the edge microlens MLS located to the right of the center O of the light-emitting area is tilted to the left, thereby realizing the converging principal ray angle (CRA) design.

[0133] For example, as shown in FIG1 or FIG2, the plurality of edge microlenses MLS include: a first edge microlens MLS1 and a second edge microlens MLS2. In the orthographic projection on the light-emitting substrate 11, the second edge microlens MLS2 is located on the side of the first edge microlens MLS1 away from the center O of the light-emitting area, and the first distance D1 of the second edge microlens MLS2 is greater than or equal to the first distance D1 of the first edge microlens MLS1.

[0134] In this way, the principal ray angle CRA of the second edge microlens MLS2 can be greater than or equal to the principal ray angle CRA of the first edge microlens MLS1. When the first distance D1 of the second edge microlens MLS2 is equal to the first distance D1 of the first edge microlens MLS1, the principal ray angle CRA of the second edge microlens MLS2 is equal to the principal ray angle CRA of the first edge microlens MLS1. When the first distance D1 of the second edge microlens MLS2 is greater than the first distance D1 of the first edge microlens MLS1, the principal ray angle CRA of the second edge microlens MLS2 is greater than the principal ray angle CRA of the first edge microlens MLS1.

[0135] As shown in Figure 1 or Figure 2, the distance between the dimming position B and the bottom surface S2 is the second distance D2.

[0136] For example, as shown in Figure 1 or Figure 2, the second distance D2 of the edge microlens MLS is greater than or equal to the second distance D2 of the central microlens MLC.

[0137] For example, as shown in Figure 1 or Figure 2, the second distance D2 of the second edge microlens MLS2 is greater than or equal to the second distance D2 of the first edge microlens MLS1.

[0138] As shown in Figure 5, the multiple edge microlenses (MLS) include a third edge microlens (MLS3) and a fourth edge microlens (MLS4). In the orthographic projection onto the light-emitting substrate 11, the distance between the third edge microlens (MLS3) and the center O of the light-emitting area is approximately equal to the distance between the fourth edge microlens (MLS4) and the center O of the light-emitting area. That is, the half-image heights of the third edge microlens (MLS3) and the fourth edge microlens (MLS4) are approximately the same.

[0139] As shown in Figure 5, the sub-emitting region EA that overlaps with the third edge microlens MLS3 is called the third sub-emitting region EA3, and the sub-emitting region EA that overlaps with the fourth edge microlens MLS4 is called the fourth sub-emitting region EA4. The third sub-emitting region EA3 and the fourth sub-emitting region EA4 are used to emit light of the same color.

[0140] To improve brightness uniformity at the same half-image height, for example, as shown in FIG5, the first distance D1 of the third edge microlens MLS3 is approximately equal to the first distance D1 of the fourth edge microlens MLS4.

[0141] To improve the brightness uniformity at the same half-image height, for example, as shown in FIG5, in the orthogonal projection on the light-emitting substrate 11, the distance between the dimming position B of the third edge microlens MLS3 and the center O of the light-emitting area is approximately equal to the distance between the dimming position B of the fourth edge microlens MLS4 and the center O of the light-emitting area.

[0142] To improve the brightness uniformity at the same half-image height, for example, as shown in FIG5, in the orthographic projection on the light-emitting substrate 11, the distance between the bottom center A of the third edge microlens MLS3 and the center O of the light-emitting area is approximately equal to the distance between the bottom center A of the fourth edge microlens MLS4 and the center O of the light-emitting area.

[0143] To improve the brightness uniformity at the same half-image height, for example, as shown in FIG5, in the orthogonal projection on the light-emitting substrate 11, the bottom surface S2 dimension L of the third edge microlens MLS3 is approximately equal to the bottom surface S2 dimension L of the fourth edge microlens MLS4.

[0144] To improve brightness uniformity at the same half-image height, for example, as shown in Figure 5, the distance D2 between the dimming position B of the third edge microlens MLS3 and the bottom surface S2 of the third edge microlens MLS3 is approximately equal to the distance D2 between the dimming position B of the fourth edge microlens MLS4 and the bottom surface S2 of the fourth edge microlens MLS4, that is, the second distance D2 of the third edge microlens MLS3 is approximately equal to the second distance D2 of the fourth edge microlens MLS4.

[0145] As shown in Figure 6, the multiple edge microlenses (MLS) include a fifth edge microlens (MLS5) and a sixth edge microlens (MLS6). In the orthographic projection onto the light-emitting substrate 11, the distance between the fifth edge microlens (MLS5) and the center O of the light-emitting area is approximately equal to the distance between the fifth edge microlens (MLS5) and the center O of the light-emitting area. That is, the half-image heights of the fifth edge microlens (MLS5) and the sixth edge microlens (MLS6) are approximately the same.

[0146] As shown in Figure 6, the sub-emitting region EA that overlaps with the fifth edge microlens MLS5 is called the fifth sub-emitting region EA5, and the sub-emitting region EA that overlaps with the sixth edge microlens MLS6 is called the sixth sub-emitting region EA6. The fifth sub-emitting region EA5 and the sixth sub-emitting region EA6 are used to emit light of different colors.

[0147] The inventors discovered that the brightness of red, green, and blue light decreases at different rates with varying viewing angles, which can easily lead to a problem of perspective distortion.

[0148] To improve the problem of large-viewing-angle offset, for example, as shown in Figure 6, the first distance D1 of the fifth edge microlens MLS5 is not equal to the first distance D1 of the sixth edge microlens MLS6.

[0149] To improve the issue of large viewing angle distortion, for example, as shown in FIG6, in the orthographic projection on the light-emitting substrate 11, the distance between the dimming position B of the fifth edge microlens MLS5 and the center O of the light-emitting area is not equal to the distance between the dimming position B of the sixth edge microlens MLS6 and the center O of the light-emitting area.

[0150] To improve the issue of large viewing angle distortion, for example, as shown in FIG6, in the orthographic projection on the light-emitting substrate 11, the distance between the bottom center A of the fifth edge microlens MLS5 and the center O of the light-emitting area is not equal to the distance between the bottom center A of the sixth edge microlens MLS6 and the center O of the light-emitting area.

[0151] To improve the issue of large viewing angle distortion, for example, as shown in FIG6, in the orthographic projection on the light-emitting substrate 11, the bottom surface S2 dimension L of the fifth edge microlens MLS5 is not equal to the bottom surface S2 dimension L of the sixth edge microlens MLS6.

[0152] To mitigate the issue of large field of view distortion, for example, as shown in Figure 6, the distance D2 between the dimming position B of the fifth edge microlens MLS5 and its bottom surface S2 is not equal to the distance D2 between the dimming position B of the sixth edge microlens MLS6 and its bottom surface S2. That is, the second distance D2 of the fifth edge microlens MLS5 is not equal to the second distance D2 of the sixth edge microlens MLS6.

[0153] To improve the light emission brightness of the display substrate, as exemplarily shown in FIG7, the display substrate includes multiple encapsulation layers 12 and multiple microlens arrays 13. The multiple encapsulation layers 12 include a first encapsulation layer 121 and a second encapsulation layer 122, and the multiple microlens arrays 13 include a first microlens array 131 and a second microlens array 132. The first encapsulation layer 121, the first microlens array 131, the second encapsulation layer 122 and the second microlens array 132 are stacked sequentially, and the first encapsulation layer 121 is disposed close to the light-emitting substrate 11.

[0154] For example, as shown in FIG7, in the first microlens array 131, the first distance D1 of the edge microlens MLS is equal to the first distance D1 of the central microlens MLC. For example, the dimming position B of each microlens ML in the first microlens array 131 coincides with the center A of the bottom surface, that is, the first distance D1 is 0.

[0155] For example, as shown in FIG7, in the first microlens array 131, the second distance D2 of the edge microlens MLS is equal to the second distance D2 of the central microlens MLC.

[0156] For example, as shown in FIG7, in the first microlens array 131, the edge microlens MLS is exactly the same as the central microlens MLC.

[0157] For example, as shown in FIG7, in the second microlens array 132, the first distance D1 of the edge microlens MLS is greater than the first distance D1 of the central microlens MLC.

[0158] For example, as shown in FIG7, in the second microlens array 132, the first distance D1 of the second edge microlens MLS2 is greater than the first distance D1 of the first microlens ML.

[0159] For example, as shown in FIG7, in the second microlens array 132, the second distance D2 of the edge microlens MLS is greater than the second distance D2 of the central microlens MLC, and the second distance D2 of the second edge microlens MLS2 is greater than the second distance D2 of the first edge microlens MLS1.

[0160] For example, the principal ray angle CRA of each microlens ML in the first microlens array 131 is 0°. Along the direction from the center O of the light-emitting area to the edge of the light-emitting area AA, the principal ray angle CRA of the microlens ML in the second microlens array 132 gradually increases.

[0161] For example, the second microlens array 132 can adopt an outward-expanding principal ray angle (CRA) design, as shown in Figure 7a. In the orthographic projection of the second microlens array 132 onto the light-emitting substrate 11, the dimming position B of the edge microlens MLS is located on the side of the bottom center A of the edge microlens MLS away from the center O of the light-emitting area.

[0162] For example, the second microlens array 132 can also adopt a cohesive principal ray angle (CRA) design, as shown in Figure 7b. In the orthographic projection of the second microlens array 132 onto the light-emitting substrate 11, the dimming position B of the edge microlens MLS is located on the side of the bottom center A of the edge microlens MLS near the center O of the light-emitting area.

[0163] For example, as shown in a or b of FIG7, the dimming surfaces S1 of the microlenses ML in the first microlens array 131 are all hemispherical, the dimming surface S1 of the central microlens MLC in the second microlens array 132 is hemispherical, and the dimming surfaces S1 of the edge microlenses MLS in the second microlens array 132 are all semi-ellipsoidal.

[0164] For example, as shown in Figure 7c, the dimming surfaces S1 of the microlenses ML in the first microlens array 131 are all Fresnel surfaces, the dimming surface S1 of the central microlens MLC in the second microlens array 132 is a hemispherical surface, and the dimming surfaces S1 of the edge microlenses MLS in the second microlens array 132 are all semi-ellipsoidal surfaces.

[0165] The following provides an exemplary description of the materials used in microlenses (MLs).

[0166] In the first example, as shown in Figure 1 or Figure 2, the material of the multiple microlenses ML is a resin material that can transmit multiple colors of visible light. The gap between two adjacent microlenses ML is greater than or equal to 0 and smaller than the gap between two adjacent sub-light-emitting regions EA. This ensures that the microlenses ML have a good light-gathering effect and maximizes the utilization of the light emitted by the light-emitting substrate 11.

[0167] In this example, the microlenses (MLs) located in different sub-pixels are made of the same material. The material of the microlenses (MLs) is, for example, capable of transmitting red, green, and blue light simultaneously.

[0168] In this example, as shown in Figure 1 or Figure 2, the display substrate further includes a color resist layer CF, located between the light-emitting substrate 11 and the encapsulation layer 12, which includes multiple color resist patterns R / G / B. The orthographic projection of the multiple color resist patterns R / G / B on the light-emitting substrate 11 covers multiple sub-light-emitting areas EA for transmitting a single color of visible light. The edges of two adjacent color resist patterns R / G / B overlap each other.

[0169] As shown in Figure 1 or Figure 2, the multiple color resist patterns R / G / B include, for example, a red color resist pattern R, which transmits red light, and in the orthographic projection on the light-emitting substrate 11, a sub-light-emitting area EA that overlaps with the red color resist pattern R is used to emit red light; a green color resist pattern G, which transmits green light, and in the orthographic projection on the light-emitting substrate 11, a sub-light-emitting area EA that overlaps with the green color resist pattern G is used to emit green light; and a blue color resist pattern B, which transmits blue light, and in the orthographic projection on the light-emitting substrate 11, a sub-light-emitting area EA that overlaps with the blue color resist pattern B is used to emit blue light.

[0170] In the second example, as shown in Figure 8, the material of the multiple microlenses ML includes a color resist material, which is used to transmit a single color of visible light, and the edges of two adjacent microlenses ML overlap each other.

[0171] This example uses color resist material to fabricate microlenses (ML), which can achieve both colorization and the effect of microlenses (ML), minimizing manufacturing processes and significantly reducing costs.

[0172] As shown in Figure 8, the plurality of microlenses ML include, for example, at least one of the following: a red microlens MLR, comprising a red color resist material for transmitting red light, and a sub-emitting region EA overlapping with the red microlens MLR in the orthographic projection on the light-emitting substrate 11 for emitting red light; a green microlens MLG, comprising a green color resist material for transmitting green light, and a sub-emitting region EA overlapping with the green microlens MLG in the orthographic projection on the light-emitting substrate 11 for emitting green light; and a blue microlens MLB, comprising a blue color resist material for transmitting blue light, and a sub-emitting region EA overlapping with the blue microlens MLB in the orthographic projection on the light-emitting substrate 11 for emitting blue light.

[0173] To improve the light-gathering effect of the microlens ML, exemplarily, as shown in FIG1 or FIG2, the display substrate further includes a leveling layer LP, located on the side of the microlens array 13 facing away from the light-emitting substrate 11. The surface of the leveling layer LP facing away from the light-emitting substrate 11 is planar, and the material of the leveling layer LP is the same as that of the microlens ML. The thickness of the leveling layer LP is, for example, greater than or equal to 0.

[0174] For example, as shown in FIG9, the light-emitting substrate 11 includes a substrate 91 and a light-emitting device LD disposed on one side of the substrate 91. The substrate 91 is, for example, a glass substrate or a silicon substrate. The light-emitting device LD can be, for example, an organic light-emitting diode (OLED), a quantum dot light-emitting diode (QLED), or a micro light-emitting diode (Micro LED).

[0175] For example, as shown in FIG9, the light-emitting substrate 11 may further include a pre-encapsulation layer 92, which is disposed on the side of the light-emitting device LD away from the substrate 91.

[0176] For example, the light-emitting device LD is an OLED, which includes a first electrode E1, a light-emitting layer EL, and a second electrode E2 stacked together, wherein the first electrode E1 is disposed close to the substrate 91.

[0177] For example, as shown in FIG9, the light-emitting substrate 11 may further include: a pixel defining layer PDL for forming a plurality of openings, a light-emitting device LD located in the openings, a first electrode E1 located between the pixel defining layer PDL and the substrate 91, and a light-emitting layer EL and a second electrode E2 located on the side of the pixel defining layer PDL away from the substrate 91.

[0178] For example, as shown in FIG9, the light-emitting substrate 11 may further include: a metal electrode 93, located between the substrate 91 and the first electrode E1, connected to the substrate 91 through a tungsten hole WK, and overlapped with the first electrode E1 through a via.

[0179] For example, as shown in FIG9, a color resist layer CF is disposed on the light-emitting side of the light-emitting substrate 11, and an encapsulation layer 12, a microlens array 13, an optical adhesive 94 and a cover plate CG are sequentially stacked on the side of the color resist layer CF away from the light-emitting substrate 11.

[0180] As shown in FIG10, this disclosure provides a display device, including a display substrate as provided in any embodiment.

[0181] Those skilled in the art will understand that the display device provided in this disclosure has the advantages of the display substrate of any of the above embodiments.

[0182] The display device disclosed herein can be any product or component with display function, such as a display module, mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, in-vehicle display device, VR / AR device, wearable device, smartwatch, fitness wristband, personal digital assistant, etc.

[0183] As shown in Figure 11, this disclosure provides a method for fabricating a display substrate, including:

[0184] Step S01: Provide a light-emitting substrate 11, which includes a light-emitting region AA and a plurality of sub-light-emitting regions EA.

[0185] Step S02: An encapsulation layer 12 is formed on the light-emitting side of the light-emitting substrate 11. The surface of the encapsulation layer 12 away from the light-emitting substrate 11 includes a plurality of recessed regions AX. The recessed regions AX are recessed towards the side closer to the light-emitting substrate 11. The encapsulation layer 12 includes a plurality of sub-encapsulation layers 14 stacked together. The recessed regions AX include openings of the plurality of sub-encapsulation layers 14.

[0186] Step S03: A microlens array 13 is formed on the side of the encapsulation layer 12 away from the encapsulation layer 12. The microlens array 13 includes multiple microlenses ML. The microlenses ML are located in the recessed region AX. The orthographic projection of the microlenses ML on the light-emitting substrate 11 overlaps at least partially with the multiple sub-light-emitting regions EA, so as to change the propagation direction of at least part of the emitted light from the multiple sub-light-emitting regions EA.

[0187] The display substrate provided in any of the above embodiments can be prepared using the preparation method provided in this disclosure.

[0188] For example, step S02 may specifically include the following steps:

[0189] Step S21: Form an encapsulation film on the light-emitting side of the light-emitting substrate 11.

[0190] Step S22: Using a grayscale mask, the encapsulation film is exposed, developed, and etched to obtain the encapsulation layer 12.

[0191] For example, step S03 may specifically include the following steps:

[0192] Step S31: Apply adhesive to the side of the encapsulation layer 12 away from the light-emitting substrate 11 to form an adhesive layer. The adhesive layer is planar on the surface away from the light-emitting substrate 11 and has a raised recessed area AX.

[0193] Step S32: Remove the adhesive layer in the non-light-emitting area AA to obtain the microlens array 13. The adhesive layer located in the concave area AX constitutes multiple microlenses ML of the microlens array 13.

[0194] For example, the adhesive layer in the non-light-emitting area AA can be removed using an exposure and development process.

[0195] The following is an exemplary description of the fabrication method of any of the display substrates shown in Figures 1 to 3, specifically including the following steps:

[0196] Step 1: Provide the light-emitting substrate 11;

[0197] Step 2: Prepare a color resist layer CF on the light-emitting side of the light-emitting substrate 11;

[0198] Step 3: An encapsulation film is formed on the side of the color resist layer CF away from the light-emitting substrate 11. Then, a grayscale mask is used to expose, develop, and etch the encapsulation film to obtain the encapsulation layer 12. The surface of the encapsulation layer 12 away from the light-emitting substrate 11 includes multiple recessed regions AX, which are recessed towards the side closer to the light-emitting substrate 11.

[0199] Step 4: Apply adhesive to the side of the encapsulation layer 12 away from the light-emitting substrate 11 to form an adhesive layer. The adhesive layer is planar on the surface away from the light-emitting substrate 11 and protrudes from the recessed area AX. Then, remove the adhesive layer in the non-light-emitting area AA to obtain the microlens array 13. The adhesive layer located in the recessed area AX constitutes multiple microlenses ML of the microlens array 13.

[0200] The following is an exemplary description of the fabrication method of the display substrate shown in Figure 7, which specifically includes the following steps:

[0201] Step 11: Provide the light-emitting substrate 11;

[0202] Step 12: Prepare a color resist layer CF on the light-emitting side of the light-emitting substrate 11;

[0203] Step 13: A first encapsulation film is formed on the side of the color resist layer CF away from the light-emitting substrate 11. Then, a grayscale mask is used to expose, develop, and etch the first encapsulation film to obtain the first encapsulation layer 121. The surface of the first encapsulation layer 121 away from the light-emitting substrate 11 includes multiple recessed regions AX, which are recessed towards the side closer to the light-emitting substrate 11.

[0204] Step 14: Apply adhesive to the side of the first encapsulation layer 121 away from the light-emitting substrate 11 to form a first adhesive layer. The surface of the first adhesive layer away from the light-emitting substrate 11 is flat and protrudes into the recessed area AX. Then, remove the first adhesive layer from the non-light-emitting area AA to obtain the first microlens array 131. The adhesive layer located in the recessed area AX constitutes multiple microlenses ML of the first microlens array 131.

[0205] Step 15: A second encapsulation film is formed on the side of the first microlens array 131 facing away from the light-emitting substrate 11. Then, a grayscale mask is used to expose, develop, and etch the second encapsulation film to obtain the second encapsulation layer 122. The surface of the second encapsulation layer 122 facing away from the light-emitting substrate 11 includes multiple recessed regions AX, which are recessed towards the side closer to the light-emitting substrate 11.

[0206] Step 16: Apply adhesive to the side of the second encapsulation layer 122 away from the light-emitting substrate 11 to form a second adhesive layer. The surface of the second adhesive layer away from the light-emitting substrate 11 is flat and protrudes from the recessed area AX. Then, remove the second adhesive layer from the non-light-emitting area AA to obtain the second microlens array 132. The adhesive layer located in the recessed area AX constitutes multiple microlenses ML of the second microlens array 132.

[0207] The following is an exemplary description of the fabrication method of the display substrate shown in Figure 8, which specifically includes the following steps:

[0208] Step 21: Provide a light-emitting substrate 11, which includes a substrate 91, a light-emitting device LD, and a pre-encapsulation layer 92 stacked sequentially.

[0209] Step 22: Using a grayscale mask, the pre-encapsulated film is exposed, developed, and etched to obtain the encapsulation layer 12. The surface of the encapsulation layer 12 facing away from the light-emitting substrate 11 includes multiple recessed regions AX, which are recessed towards the side closer to the light-emitting substrate 11.

[0210] Step 23: Apply color resist material to the side of the encapsulation layer 12 away from the light-emitting substrate 11 to form a color resist film. The surface of the color resist film away from the light-emitting substrate 11 is flat and protrudes from the recessed area AX. Then, remove the color resist film in the non-light-emitting area AA to obtain the microlens array 13. The color resist film located in the recessed area AX constitutes the microlens ML of the microlens array 13.

[0211] The method for fabricating the display substrate shown in Figure 8 is relatively simple, which can simplify the process steps and reduce costs.

[0212] In this disclosure, "multiple" means two or more, and "at least one" means one or more, unless otherwise expressly and specifically defined.

[0213] In this disclosure, the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this disclosure.

[0214] In this disclosure, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0215] The terms "an embodiment," "some embodiments," "exemplary embodiments," "one or more embodiments," "example," "one example," "some examples," etc., used in this disclosure are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be included in any suitable manner in any one or more embodiments or examples.

[0216] In this disclosure, relational terms such as first and second are used merely to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0217] In this specification, "electrical connection" and "coupling" include situations where components are connected together by elements that have some electrical function. There are no particular limitations on what constitutes an "electrical function," as long as it allows for the transmission and reception of electrical signals between the connected components. Examples of "electrical functions" include not only electrodes and wiring, but also switching elements such as transistors, resistors, inductors, capacitors, and other components with various functions.

[0218] In this specification, the term "same-layer arrangement" refers to a structure formed by patterning two (or more) structures through the same patterning process, and their materials may be the same or different. For example, the precursors forming multiple structures in a same-layer arrangement may be made of the same material, while the final materials may be the same or different.

[0219] The polygons used in this specification are not strictly defined; they can be approximate triangles, rectangles, trapezoids, pentagons, or hexagons, etc. They may have minor deformations due to tolerances, and may include chamfers, fillets, curved edges, and other variations.

[0220] "At least one of A, B and C" has the same meaning as "at least one of A, B or C", both including the following combinations of A, B and C: only A, only B, only C, combinations of A and B, combinations of A and C, combinations of B and C, and combinations of A, B and C.

[0221] "A and / or B" includes the following three combinations: A only, B only, and a combination of A and B.

[0222] The use of “for” or “configured to” in this disclosure implies an open and inclusive language that does not preclude applicability to or configuration to devices for performing additional tasks or steps.

[0223] As used in this disclosure, “about,” “approximately,” or “approximately” includes the stated value and the average value within an acceptable range of deviation from the given value, wherein the acceptable range of deviation is determined by a person skilled in the art taking into account the measurement under discussion and the error associated with the measurement of the given quantity (i.e., the limitations of the measurement system).

[0224] As used in this disclosure, "parallel," "perpendicular," "equal," and "flush" include the described situation and situations that are similar to the described situation, within an acceptable deviation range, which is determined by those skilled in the art taking into account the measurement under discussion and the error associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein an acceptable deviation range for approximate parallelism may be, for example, within 10° or 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein an acceptable deviation range for approximate perpendicularity may also be, for example, within 10° or 5°. "Equal" includes absolute equality and approximate equality, wherein an acceptable deviation range for approximate equality may be, for example, a difference between the two equals being less than or equal to 5% of either one. "Flush" includes absolute flush and approximate flush, wherein an acceptable deviation range for approximate flush may be, for example, a distance between the flushes being less than or equal to 5% of either one's dimension.

[0225] It should be understood that when a layer or element is referred to as being on another layer or substrate, it can mean that the layer or element is directly on the other layer or substrate, or that there is an intermediate layer between the layer or element and the other layer or substrate.

[0226] This disclosure describes exemplary embodiments with reference to cross-sectional views and / or plan views as idealized exemplary drawings. In the drawings, the thickness of layers and regions is enlarged for clarity. Therefore, variations in shape relative to the drawings are contemplated due to, for example, manufacturing techniques and / or tolerances. Thus, exemplary embodiments should not be construed as being limited to the shapes of the regions shown in this disclosure, but rather include shape deviations due to, for example, manufacturing processes. For example, etched regions shown as rectangular would typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to show the actual shapes of the regions of the device, nor are they intended to limit the scope of the exemplary embodiments.

[0227] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this disclosure may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0228] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A display substrate, comprising: A light-emitting substrate includes a light-emitting region, wherein the light-emitting region includes a plurality of sub-light-emitting regions; An encapsulation layer is disposed on the light-emitting side of the light-emitting substrate. The surface of the encapsulation layer away from the light-emitting substrate includes multiple recessed areas. The multiple recessed areas are recessed toward the side closer to the light-emitting substrate. The encapsulation layer includes multiple sub-encapsulation layers stacked together. The multiple recessed areas include openings of the multiple sub-encapsulation layers. as well as A microlens array is located on the side of the encapsulation layer opposite to the encapsulation layer. The microlens array includes multiple microlenses located within multiple recessed areas. The orthographic projections of the multiple microlenses on the light-emitting substrate at least partially overlap with the multiple sub-light-emitting areas to change the propagation direction of at least part of the emitted light from the multiple sub-light-emitting areas.

2. The display substrate according to claim 1, wherein, The plurality of microlenses includes: In the orthographic projection onto the light-emitting substrate, the edge microlens is located on the side of the central microlens away from the center of the light-emitting area, and the principal ray angle of the edge microlens is greater than or equal to the principal ray angle of the central microlens.

3. The display substrate according to claim 2, wherein, Along the direction from the center of the light-emitting area to the edge of the light-emitting area, the main ray angle of the plurality of microlenses gradually increases.

4. The display substrate according to claim 1, wherein, The microlens includes an interconnected dimming surface and a bottom surface. The dimming surface is disposed close to the encapsulation layer, and the bottom surface is disposed away from the encapsulation layer. The dimming surface includes a dimming position, and the distance between the dimming position and the bottom surface is greater than the distance between the non-dimming position and the bottom surface. In the orthographic projection onto the light-emitting substrate, the distance between the dimming position and the center of the bottom surface is a first distance. The plurality of microlenses includes a central microlens and edge microlenses. In the orthographic projection on the light-emitting substrate, the edge microlenses are located on the side of the central microlens away from the center of the light-emitting area, and the first distance of the edge microlenses is greater than or equal to the first distance of the central microlens.

5. The display substrate according to claim 4, wherein, In the orthographic projection on the light-emitting substrate, the dimming position of the central microlens coincides with the center of the bottom surface of the central microlens, while the dimming position of the edge microlens is offset from the center of the bottom surface of the edge microlens.

6. The display substrate according to claim 5, wherein, In the orthographic projection onto the light-emitting substrate, the dimming position of the edge microlens is located on the side of the bottom surface of the edge microlens away from the center of the light-emitting area.

7. The display substrate according to claim 5, wherein, In the orthographic projection onto the light-emitting substrate, the dimming position of the edge microlens is located on the side of the bottom surface of the edge microlens closer to the center of the light-emitting area.

8. The display substrate according to claim 6 or 7, wherein, The plurality of said edge microlenses include: In the orthographic projection onto the light-emitting substrate, the second edge microlens is located on the side of the first edge microlens away from the center of the light-emitting area, and the first distance of the second edge microlens is greater than or equal to the first distance of the first edge microlens.

9. The display substrate according to claim 8, wherein, The distance between the dimming position and the bottom surface is the second distance. The second distance of the edge microlens is greater than or equal to the second distance of the central microlens, and the second distance of the second edge microlens is greater than or equal to the second distance of the first edge microlens.

10. The display substrate according to claim 6 or 7, wherein, The plurality of edge microlenses include a third edge microlens and a fourth edge microlens. In the orthographic projection on the light-emitting substrate, the distance between the third edge microlens and the center of the light-emitting area is approximately equal to the distance between the fourth edge microlens and the center of the light-emitting area. The sub-light-emitting area that overlaps with the third edge microlens is the third sub-light-emitting area, and the sub-light-emitting area that overlaps with the fourth edge microlens is the fourth sub-light-emitting area. The third sub-light-emitting area and the fourth sub-light-emitting area are used to emit light of the same color. The first distance of the third edge microlens is approximately equal to the first distance of the fourth edge microlens; In the orthographic projection onto the light-emitting substrate, the distance between the dimming position of the third edge microlens and the center of the light-emitting area is approximately equal to the distance between the dimming position of the fourth edge microlens and the center of the light-emitting area; the distance between the center of the bottom surface of the third edge microlens and the center of the light-emitting area is approximately equal to the distance between the center of the bottom surface of the fourth edge microlens and the center of the light-emitting area; and the bottom surface dimension of the third edge microlens is approximately equal to the bottom surface dimension of the fourth edge microlens. The distance between the dimming position of the third edge microlens and the bottom surface of the third edge microlens is approximately equal to the distance between the dimming position of the fourth edge microlens and the bottom surface of the fourth edge microlens.

11. The display substrate according to claim 6 or 7, wherein, The plurality of edge microlenses include a fifth edge microlens and a sixth edge microlens. In the orthographic projection on the light-emitting substrate, the distance between the fifth edge microlens and the center of the light-emitting area is approximately equal to the distance between the fifth edge microlens and the center of the light-emitting area. The sub-light-emitting area that overlaps with the fifth edge microlens is the fifth sub-light-emitting area, and the sub-light-emitting area that overlaps with the sixth edge microlens is the sixth sub-light-emitting area. The fifth sub-light-emitting area and the sixth sub-light-emitting area are used to emit light of different colors. The first distance of the fifth edge microlens is not equal to the first distance of the sixth edge microlens; and / or, In the orthographic projection onto the light-emitting substrate, the distance between the dimming position of the fifth edge microlens and the center of the light-emitting area is not equal to the distance between the dimming position of the sixth edge microlens and the center of the light-emitting area, and / or, the distance between the center of the bottom surface of the fifth edge microlens and the center of the light-emitting area is not equal to the distance between the center of the bottom surface of the sixth edge microlens and the center of the light-emitting area, and / or, the bottom surface dimension of the fifth edge microlens is not equal to the bottom surface dimension of the sixth edge microlens; and / or, The distance between the dimming position of the fifth edge microlens and the bottom surface of the fifth edge microlens is not equal to the distance between the dimming position of the sixth edge microlens and the bottom surface of the sixth edge microlens.

12. The display substrate according to any one of claims 4 to 7, wherein, The display substrate includes a plurality of encapsulation layers and a plurality of microlens arrays. The plurality of encapsulation layers include a first encapsulation layer and a second encapsulation layer. The plurality of microlens arrays include a first microlens array and a second microlens array. The first encapsulation layer, the first microlens array, the second encapsulation layer, and the second microlens array are stacked sequentially. The first encapsulation layer is disposed close to the light-emitting substrate. In the first microlens array, the first distance between the edge microlenses is equal to the first distance between the central microlens; and In the second microlens array, the first distance of the edge microlens is greater than the first distance of the central microlens.

13. The display substrate according to any one of claims 4 to 7, wherein, The bottom surface is a plane, and the dimming surface includes at least one of the following: a portion of a sphere, a portion of an ellipsoid, a Fresnel surface, and a freeform surface.

14. The display substrate according to any one of claims 1 to 7, wherein, The material of the plurality of microlenses is a resin material that can transmit multiple colors of visible light. The gap between two adjacent microlenses is greater than or equal to 0 and smaller than the gap between two adjacent sub-light-emitting regions.

15. The display substrate according to claim 14, wherein, The display substrate further includes: A color resist layer, located between the light-emitting substrate and the encapsulation layer, includes multiple color resist patterns. The orthographic projection of the multiple color resist patterns on the light-emitting substrate covers the multiple sub-light-emitting areas, and is used to transmit a single color of visible light. The edges of two adjacent color resist patterns overlap each other.

16. The display substrate according to any one of claims 1 to 7, wherein, The materials of the plurality of microlenses include color resist materials, which are used to transmit a single color of visible light, and the edges of two adjacent microlenses overlap each other.

17. The display substrate according to any one of claims 1 to 7, wherein, The plurality of microlenses includes at least one of the following: A red microlens, comprising a red color resist material, is used to transmit red light. In the orthogonal projection on the light-emitting substrate, the sub-light-emitting area overlapping with the red microlens is used to emit red light. The green microlens, including a green color resist material, is used to transmit green light. In the orthogonal projection on the light-emitting substrate, the sub-light-emitting area that overlaps with the green microlens is used to emit green light. as well as The blue microlens, comprising a blue color resist material, is used to transmit blue light. In the orthogonal projection onto the light-emitting substrate, the sub-light-emitting area overlapping with the blue microlens is used to emit blue light.

18. The display substrate according to claim 1, wherein each of the plurality of sub-encapsulation layers is an inorganic sub-encapsulation layer or an organic sub-encapsulation layer, the encapsulation layer comprising the inorganic sub-encapsulation layer and the organic sub-encapsulation layer arranged alternately in sequence, the sub-encapsulation layer disposed near the light-emitting substrate being the inorganic sub-encapsulation layer, and the sub-encapsulation layer disposed away from the light-emitting substrate being the inorganic sub-encapsulation layer or the organic sub-encapsulation layer, wherein the inorganic sub-encapsulation layer comprises an inorganic material, and the organic sub-encapsulation layer comprises an organic material.

19. The display substrate according to claim 1, wherein at least one of the microlenses in the microlens array is a tilted microlens, the principal ray angle of the tilted microlens is greater than 0°, and the principal ray angle is the angle between the principal ray of the microlens and the normal direction of the light-emitting substrate.

20. The display substrate according to claim 12, wherein in the first microlens array, the second distance of the edge microlenses is equal to the second distance of the central microlens; and In the second microlens array, the second distance of the edge microlenses is greater than the second distance of the central microlens.

21. The display substrate according to claim 1, wherein the display substrate further comprises: A leveling layer is located on the side of the microlens array facing away from the light-emitting substrate. The surface of the leveling layer facing away from the light-emitting substrate is planar, and the material of the leveling layer is the same as that of the multiple microlenses.

22. The display substrate according to claim 1, wherein the light-emitting substrate includes a substrate and a light-emitting device disposed on one side of the substrate.

23. The display substrate according to claim 22, wherein the light-emitting substrate further comprises: A pre-encapsulation layer is disposed on the side of the light-emitting device opposite to the substrate.

24. The display substrate according to claim 22, wherein the light-emitting device is an OLED, comprising a first electrode, a light-emitting layer, and a second electrode stacked thereon, wherein, The first electrode is disposed close to the substrate.

25. The display substrate according to claim 24, wherein the light-emitting substrate further comprises: A pixel defining layer is used to form a plurality of openings, the light-emitting device is located within the plurality of openings, the first electrode is located between the pixel defining layer and the substrate, and the light-emitting layer and the second electrode are located on the side of the pixel defining layer opposite to the substrate.

26. The display substrate according to claim 24, wherein the light-emitting substrate 11 further comprises: A metal electrode is located between the substrate and the first electrode, connected to the substrate through a tungsten hole, and overlapped with the first electrode through a via.

27. A display device comprising a display substrate as described in any one of claims 1 to 26.

28. A method for preparing a display substrate, comprising: A light-emitting substrate is provided, the light-emitting substrate including a light-emitting region, the light-emitting region including a plurality of sub-light-emitting regions; An encapsulation layer is formed on the light-emitting side of the light-emitting substrate. The surface of the encapsulation layer away from the light-emitting substrate includes multiple recessed areas. The multiple recessed areas are recessed toward the side closer to the light-emitting substrate. The encapsulation layer includes multiple sub-encapsulation layers stacked together. The multiple recessed areas include openings of the multiple sub-encapsulation layers. as well as A microlens array is formed on the side of the encapsulation layer away from the encapsulation layer. The microlens array includes multiple microlenses located in multiple recessed areas. The orthogonal projection of the multiple microlenses on the light-emitting substrate at least partially overlaps with the multiple sub-light-emitting areas to change the propagation direction of at least part of the emitted light from the multiple sub-light-emitting areas.

29. The method for preparing a display substrate according to claim 28, wherein, The step of forming an encapsulation layer on the light-emitting side of the light-emitting substrate includes: An encapsulation film is formed on the light-emitting side of the light-emitting substrate; and Using a grayscale mask, the encapsulation film is exposed, developed, and etched to obtain the encapsulation layer; and The step of forming a microlens array on the side of the encapsulation layer opposite to the encapsulation layer includes: An adhesive layer is formed by applying adhesive to the side of the encapsulation layer opposite to the light-emitting substrate. The adhesive layer is planar on the surface opposite to the light-emitting substrate and protrudes from the plurality of recessed areas. The adhesive layer in the non-light-emitting area is removed to obtain the microlens array. The adhesive layer located in the plurality of recessed areas constitutes the plurality of microlenses of the microlens array.

30. The method for preparing a display substrate according to claim 28, wherein, The light-emitting substrate includes a substrate, a light-emitting device, and a pre-encapsulation layer stacked sequentially. The step of forming an encapsulation layer on the light-emitting side of the light-emitting substrate includes: Using a grayscale mask, the pre-encapsulation layer is exposed, developed, and etched to obtain the encapsulation layer; and The step of forming a microlens array on the side of the encapsulation layer opposite to the encapsulation layer includes: A color resist material is coated on the side of the encapsulation layer away from the light-emitting substrate to form a color resist film. The surface of the color resist film away from the light-emitting substrate is planar and has protruding recessed areas. Then, the color resist film in the non-light-emitting area is removed to obtain the microlens array.

31. The method for preparing a display substrate according to claim 29, wherein, The adhesive layer in the non-light-emitting area is removed using an exposure and development process.

32. The method for preparing a display substrate according to claim 29, wherein, Before the step of forming an encapsulation film on the light-emitting side of the light-emitting substrate, the method includes: A color resist layer is prepared on the light-emitting side of the light-emitting substrate; and The encapsulation film is formed on the side of the color resist layer opposite to the light-emitting substrate.

33. A method for preparing a display substrate, comprising: Provide light-emitting substrates; A color resist layer is prepared on the light-emitting side of the light-emitting substrate; A first encapsulation film is formed on the side of the color resist layer away from the light-emitting substrate. Then, a grayscale mask is used to expose, develop and etch the first encapsulation film to obtain a first encapsulation layer. The surface of the first encapsulation layer away from the light-emitting substrate includes multiple recessed areas, which are recessed toward the side closer to the light-emitting substrate. A first adhesive layer is formed by applying adhesive to the side of the first encapsulation layer away from the light-emitting substrate. The surface of the first adhesive layer away from the light-emitting substrate is planar and protrudes from the plurality of recessed areas. The first adhesive layer in the non-light-emitting area is then removed to obtain a first microlens array. The adhesive layers located in the plurality of recessed areas constitute a plurality of microlenses in the first microlens array. A second encapsulation film is formed on the side of the first microlens array away from the light-emitting substrate. Then, a grayscale mask is used to expose, develop and etch the second encapsulation film to obtain a second encapsulation layer. The surface of the second encapsulation layer away from the light-emitting substrate includes multiple recessed areas, which are recessed toward the side closer to the light-emitting substrate. as well as A second adhesive layer is formed by applying adhesive to the side of the second encapsulation layer away from the light-emitting substrate. The surface of the second adhesive layer away from the light-emitting substrate is planar and protrudes from the plurality of recessed areas. Then, the second adhesive layer in the non-light-emitting area is removed to obtain a second microlens array. The adhesive layer located in the plurality of recessed areas constitutes a plurality of microlenses in the second microlens array.

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