Light-emitting substrate and display module

Abstract

Disclosed are a light-emitting substrate and a display module. The light-emitting substrate comprises: a light guide substrate; a light-emitting component arranged on one side of the light guide substrate, the light-emitting component comprising a light-emitting surface; the light guide substrate comprising a first bottom surface away from the light-emitting device; the light guide substrate is internally provided with a reflection structure, the reflection structure having a first longitudinal section, the first longitudinal section comprising a bottom edge away from the light-emitting component, the bottom edge comprising a first end point and a second end point, the bottom edge, together with a first reference line segment and a second reference line segment, forming a first triangle, the first reference line segment passing through the first end point and forming a first included angle with the bottom edge, the second reference line segment passing through the second end point and forming a second included angle with the bottom edge, the first included angle and the second included angle both being between 47° and 52°; the first longitudinal section is located within the first triangle, the light-emitting surface intersecting a plane on which the first longitudinal section is located to form a third reference line segment, the third reference line segment being located within the first triangle.

Description

Technical Field

[0001] This disclosure belongs to the field of display technology, specifically relating to a light-emitting substrate and a display module. Background Technology

[0002] In liquid crystal display devices, backlight modules are used to provide backlight for the liquid crystal display panel. In direct-lit backlight modules, in order to achieve the requirement of backlight uniformity, optical films such as prism films and diffusion films are usually placed on the light-emitting side of the light-emitting device. In addition, a certain light mixing distance needs to be reserved between the light-emitting device and the optical films, which increases the thickness and cost of the backlight module. Summary of the Invention

[0003] In order to at least solve one of the above-mentioned technical problems, this disclosure provides a light-emitting substrate and a display module.

[0004] This disclosure provides a light-emitting substrate, comprising:

[0005] Light guide substrate;

[0006] A light-emitting component is disposed on one side of the light guide substrate, the light-emitting component including a light-emitting surface facing the light guide substrate; the light guide substrate includes a first bottom surface away from the light-emitting device;

[0007] The light guide substrate has a reflective structure inside. Along the direction away from the light-emitting component, the cross-section of the reflective structure parallel to the first bottom surface gradually increases. The side of the reflective structure is used to reflect the light emitted from the light-emitting surface.

[0008] The reflective structure has a first longitudinal section passing through its central axis. The first longitudinal section includes a bottom edge away from the light-emitting component. The bottom edge includes a first endpoint and a second endpoint. The bottom edge, together with a first reference line segment and a second reference line segment, forms a first triangle. The first reference line segment and the second reference line segment are both located on the side of the straight line containing the bottom edge away from the first bottom surface. The first reference line segment passes through the first endpoint and forms a first angle with the bottom edge. The second reference line segment passes through the second endpoint and forms a second angle with the bottom edge. Both the first angle and the second angle are between 47° and 52°.

[0009] The first longitudinal section is located within the first triangle, and the light-emitting surface intersects the plane containing the first longitudinal section at a third reference line segment, which is located within the first triangle.

[0010] In some embodiments, the two ends of the third reference line segment are in contact with the first reference line segment and the second reference line segment, respectively.

[0011] In some embodiments, the light-emitting substrate further includes a first filling layer, which is located between the light-emitting surface and the light-guiding substrate, and the first filling layer is in contact with the light-emitting surface of the light-emitting component and the light-guiding substrate respectively.

[0012] The material of the first filler layer includes one of polymethyl methacrylate, polycarbonate, cyclic polyolefin, cyclic olefin copolymer, methyl methacrylate-styrene copolymer, and nanocomposite materials.

[0013] In some embodiments, the light guide substrate further includes a first top surface facing the light-emitting component, the first reference line segment intersects the first top surface at a third endpoint, the second reference line segment intersects the first top surface at a fourth endpoint, and the line connecting the third endpoint and the fourth endpoint is the fourth reference line segment;

[0014] A first filling layer exists between the light-emitting surface and the light guide substrate. The refractive index of the first filling layer is n2, and the refractive index of the light guide substrate is n1; 1 < n2 ≤ n1.

[0015] The fourth reference line segment, together with the fifth and sixth reference line segments, forms a second triangle, which is located within the first triangle. The fifth reference line segment passes through the third endpoint and forms an angle with the fourth reference line segment. The sixth reference line segment passes through the fourth endpoint and forms an angle with the fourth reference line segment. A1 is the first included angle, and A2 is the second included angle;

[0016] The third reference line segment is located inside the second triangle.

[0017] In some embodiments, the light-emitting component includes a light-emitting device and a color conversion section located on the side of the light-emitting device facing the light guide substrate. The light-emitting device is used to emit a first light, which is blue light or ultraviolet light. The color conversion section is used to convert the first light into white light for emission. The light-emitting surface is the area on the surface of the color conversion section facing the light guide substrate from which the white light is emitted.

[0018] In some embodiments, the light-emitting device includes: a light-emitting body and a first electrode and a second electrode electrically connected to the light-emitting body, wherein the first electrode and the second electrode are located on the side of the light-emitting body facing the light guide substrate;

[0019] The light guide substrate is further provided with a first pad, a second pad, and a limiting dam on the side facing the light-emitting device. The first electrode is electrically connected to the first pad, and the second electrode is electrically connected to the second pad.

[0020] The defined dam has a receiving groove, which is located between the first electrode and the second electrode, and the color conversion part is located in the receiving groove.

[0021] In some embodiments, the first longitudinal section further includes two side edges connected to the two ends of the bottom edge, the two side edges being located on opposite sides of the central axis of the reflective structure, and the two ends of the third reference line segment being located on opposite sides of the reflective central structure; a first reflection point exists on the side edge, the first reflection point being able to reflect the first light ray incident on the corresponding end of the third reference line segment toward the first reflection point in a direction away from the side edge, wherein at least one of the first reflection points satisfies a first preset condition, the first preset condition being: β+2γ is greater than or equal to the largest of the first included angle and the second included angle;

[0022] Where γ = arctan k, k is the slope of the tangent at the first reflection point; β is the angle between the incident direction of the first ray when it strikes the first reflection point and the thickness direction of the light guide substrate. When the distance from the end of the third reference line segment to the central axis of the reflective structure is greater than the distance from the first reflection point to the central axis of the reflective structure, β takes a negative value; when the distance from the end of the third reference line segment to the central axis of the reflective structure is less than the distance from the first reflection point to the central axis of the reflective structure, β takes a positive value.

[0023] In some embodiments, there are multiple first reflection points on the side, and each of the first reflection points satisfies the first preset condition.

[0024] In some embodiments, the first longitudinal section further includes two side sides that are respectively connected to the two ends of the bottom edge, the two side sides being located on opposite sides of the central axis of the reflective structure, and the two ends of the third reference line segment being located on opposite sides of the reflective central structure.

[0025] There are a second reflection point and a third reflection point on the side. The second light ray that is directed toward the second reflection point from the end of the third reference line segment near the second reflection point can be reflected by the second reflection point to the third reflection point and reflected by the third reflection point in a direction away from the side. At least one of the second reflection points satisfies a second preset condition. The second preset condition includes: (2C+2)γ1-(2C+1)|β'|-180C is greater than or equal to the largest of the first included angle and the second included angle.

[0026] Wherein, γ1 is the acute angle between the tangent of the second reflection point and the bottom edge; |β'| is the absolute value of the angle between the incident direction of the second ray when it is incident on the second reflection point and the thickness direction of the light guide substrate; C is a constant related to β' and γ1.

[0027] In some embodiments, there are multiple second reflection points and multiple third reflection points on the side, and each second reflection point satisfies the second preset condition.

[0028] In some embodiments, the light guide substrate further includes a first top surface facing the light-emitting component, wherein the vertical distance between the end of the reflective structure near the light-emitting component and the first top surface is less than or equal to 1 / 10 of the height of the reflective structure.

[0029] The first longitudinal section also includes two side edges that are respectively connected to the two ends of the bottom edge. The two side edges are concave arc-shaped edges and are symmetrically arranged about the central axis of the reflective structure.

[0030] In some embodiments, the length of the bottom edge of the first longitudinal section is less than or equal to 110 micrometers; the radius of curvature at each position on the arc edge of the first longitudinal section is between 235 and 295 micrometers; the length of the third reference line segment is less than or equal to 54 micrometers; and the height of the reflective structure is between 5 and 5.2 micrometers.

[0031] In some embodiments, the length of the third reference line segment is between 75 and 85 micrometers;

[0032] The radius of curvature at various positions on the arc-shaped edge of the first longitudinal section is between 157.3 and 260 micrometers, and the length of the bottom edge of the first longitudinal section is greater than or equal to 300 micrometers; the height of the reflective structure is between 47.7 and 110 micrometers.

[0033] In some embodiments, the light guide substrate includes:

[0034] A first body portion, wherein the first body portion has a groove surrounding the reflective structure, and the opening of the groove faces the light-emitting device;

[0035] The second body portion is filled in the groove;

[0036] The second body portion has the same refractive index as the first body portion.

[0037] In some embodiments, the reflective structure includes a main body and a first reflective layer located on the side of the main body, the main body and the first body portion being an integral structure; the cross-section of the main body parallel to the first bottom surface gradually increases along the direction away from the light-emitting component.

[0038] In some embodiments, the light-emitting substrate further includes a second reflective layer, the second reflective layer being located on the side of the light-guiding substrate facing the light-emitting device;

[0039] The light guide substrate includes a plurality of light-collecting structures adjacent to the second reflective layer. Each light-collecting structure includes a reflective surface that protrudes toward or away from the first bottom surface; or, the light-collecting structure is used to scatter light.

[0040] In some embodiments, the maximum feature size of the orthographic projection of the light-collecting structure onto the first bottom surface is D, the height of the light-collecting structure is H, and the ratio of D to H is between 0.5 and 4.7.

[0041] In some embodiments, the light-collecting structure is a recessed structure located on the side of the light guide substrate away from the first bottom surface, and a portion of the second reflective layer is located in the recessed structure and is attached to the inner surface of the recessed structure;

[0042] Alternatively, the light-collecting structure is a raised structure located on the side of the light guide substrate away from the first bottom surface, and the surface of the raised structure is attached to the second reflective layer;

[0043] Alternatively, the light-collecting structure may include a recessed structure located on the side of the light guide substrate away from the first bottom surface, and a scattering material filled in the recessed structure.

[0044] In some embodiments, the light-emitting substrate further includes:

[0045] A third reflective layer, at least a portion of which is located on the side of the light-emitting component away from the light guide substrate.

[0046] This disclosure also provides a display module, including:

[0047] In the aforementioned light-emitting substrate, the number of light-emitting components is multiple, and the multiple light-emitting components are arranged in an array on the light guide substrate;

[0048] The liquid crystal display panel is located on the side of the light guide substrate away from the light-emitting component. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of a light-emitting substrate provided in some embodiments of this disclosure.

[0050] Figure 2 This is a schematic diagram illustrating the positional relationship between the light-emitting surface of the light-emitting component and the reflective structure provided in some embodiments of this disclosure.

[0051] Figure 3This is a schematic diagram illustrating another positional relationship between the light-emitting surface of the light-emitting component and the reflective structure provided in some embodiments of this disclosure.

[0052] Figure 4 This is a schematic diagram illustrating the fabrication process of the light guide substrate and reflective structure provided in some embodiments of this disclosure.

[0053] Figure 5 This is a schematic diagram illustrating another fabrication process of the light guide substrate and reflective structure provided in some embodiments of this disclosure.

[0054] Figure 6 This is a diagram showing two optical paths of light being reflected once by a reflective structure, as provided in some embodiments of this disclosure.

[0055] Figure 7 These are two optical path diagrams showing how light is reflected twice by a reflecting structure, as provided in some embodiments of this disclosure.

[0056] Figure 8 This is a schematic diagram showing the dimensions of the reflective structure provided in the embodiments of this disclosure.

[0057] Figure 9 This is a data graph showing the relevant parameters of the light-emitting component when the diameter of the reflective structure is 110 micrometers.

[0058] Figure 10 This is a graph showing the relationship between the length of the third reference line segment and the etching thickness and thinning thickness.

[0059] Figure 11 A schematic diagram showing the height of the reflective structure.

[0060] Figure 12 This is a schematic diagram of the specific structure of the light-emitting substrate provided in some embodiments of this disclosure. Detailed Implementation

[0061] To enable those skilled in the art to better understand the technical solutions of this disclosure, the disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0062] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “a,” “an,” “an,” “the,” and similar words used in this disclosure do not indicate quantity limitation and may indicate singular or plural. The terms “comprising,” “including,” “having,” and any variations thereof used in this disclosure are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may also include steps or units not listed, or may include other steps or units inherent to such processes, methods, products, or devices. The terms “connected,” “linked,” “coupled,” and similar words used in this disclosure are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. “Multiple” in this disclosure refers to two or more. “And / or” describes the relationship between related objects, indicating that three relationships may exist; for example, “A and / or B” can indicate: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following objects are in an "or" relationship. The terms "first," "second," "third," etc., used in this disclosure are merely to distinguish similar objects and do not represent a specific ordering of objects. "Above," "below," "left," "right," etc., are only used to indicate relative positional relationships; when the absolute position of the described objects changes, the relative positional relationship may also change accordingly.

[0063] Figure 1 This is a schematic diagram of a light-emitting substrate provided in some embodiments of this disclosure, such as... Figure 1 As shown, the light-emitting substrate includes: a light guide substrate 10 and a light-emitting component 20 disposed on one side of the light guide substrate 10. The light-emitting component 20 includes a light-emitting surface facing the light guide substrate 10. The light guide substrate 10 includes a first bottom surface 101 away from the light-emitting device 21 and a first top surface facing the light-emitting device 21.

[0064] The light guide substrate 10 has a reflective structure 30 inside. Along the direction away from the light-emitting component 20, the cross-section of the reflective structure 30 parallel to the first bottom surface 101 gradually increases. The side of the reflective structure 30 is used to reflect the light emitted from the light-emitting surface.

[0065] The reflective structure 30 and the light guide substrate 10 can be different structures made of different materials; or, a part of the reflective structure 30 is made of the same material as the light guide substrate 10, and a part of the reflective structure 30 and the light guide substrate 10 are formed as an integral structure.

[0066] Figure 2 This is a schematic diagram illustrating the positional relationship between the light-emitting surface of the light-emitting component 20 and the reflective structure 30 in some embodiments of this disclosure. Figure 3 This is a schematic diagram illustrating another positional relationship between the light-emitting surface of the light-emitting component 20 and the reflective structure 30 provided in some embodiments of this disclosure, such as... Figure 2 and Figure 3 As shown, the reflective structure 30 has a first longitudinal section M1 passing through its central axis. The central axis of the reflective structure 30 can be considered as an axis passing through the geometric center of the orthographic projection of the reflective structure 30 onto the first bottom surface 101 and extending along the thickness direction of the light guide substrate 10.

[0067] The first longitudinal section M1 includes a bottom edge B0 away from the light-emitting component 20. The bottom edge B0 includes a first endpoint b and a second endpoint c. The bottom edge B0, together with the first reference line segment L1 and the second reference line segment L2, forms a first triangle. The first reference line segment L1 and the second reference line segment L2 are both located on the side of the line containing the bottom edge B0 away from the first bottom surface 101. The first reference line segment L1 passes through the first endpoint and forms a first angle A1 with the bottom edge B0. The second reference line segment L2 passes through the second endpoint c and forms a second angle A2 with the bottom edge B0. The first angle A1 and the second angle A2 are related to the refractive index of the light guide substrate 10. Specifically, the first angle A1 and the second angle A2 are both complementary angles of the critical angle at which total internal reflection occurs at the interface between the light guide substrate 10 and the air when light is incident from inside the light guide substrate 10 to the outside air. For example, the material of the light guide substrate 10 includes glass, the critical angle for total internal reflection is between 38° and 43°, and the first included angle A1 and the second included angle A2 are both between 47° and 52°. For example, the refractive index of the material of the light guide substrate 10 is 1.5, and the first included angle A1 and the second included angle A2 are both 48°.

[0068] The first longitudinal section M1 is located within the first triangle △abc. The position of the light-emitting surface satisfies the triangle principle, which includes the following condition: the light-emitting surface intersects the plane containing the first longitudinal section M1, and the line of intersection is the third reference line segment L3, which is located within the first triangle △abc.

[0069] It should be noted that the first reference line segment L1 and the second reference line segment L2 in the embodiments of this disclosure are not physical structures, but auxiliary lines made to illustrate the structure of the light-emitting substrate.

[0070] In this embodiment, after the light from the light-emitting component 20 is incident on the light guide substrate 10, at least a portion of the light can undergo total internal reflection within the light guide substrate 10, thereby propagating along the light guide substrate 10. A light-collecting structure can be provided on the light guide substrate 10 to change the direction of the light propagating through total internal reflection within the light guide substrate 10, thus allowing the light to exit the light guide substrate 10. Through the light-guiding function of the light guide substrate 10, the light from the light-emitting component 20 can be uniformly dispersed, eliminating the need for prism sheets, diffusers, or other optical films, and eliminating the need for a pre-reserved light mixing distance, thereby reducing the thickness of the display module and lowering production costs. Furthermore, the third reference line segment L3 on the light-emitting surface of the light-emitting component 20 is located within the first triangle △abc. The angle between the extension lines of the two sides of the first triangle △abc and the first base surface 101 is between 47° and 52°. Therefore, the reflective structure can block at least a portion of the small-angle light emitted from the light-emitting component 20, reducing or preventing direct light leakage from the light-emitting substrate. The so-called "direct light leakage" refers to the fact that small-angle light emitted from the light-emitting component 20 does not undergo total internal reflection within the light guide substrate 10 and is directly emitted out of the light guide substrate 10.

[0071] In some embodiments, the reflective structure 30 is a conical structure or a frustum-shaped structure. For example, the reflective structure 30 is a conical or frustum-shaped structure.

[0072] In some embodiments, the first longitudinal section M1 includes two side sides B1 connected to the bottom side B0. The two side sides B1 are mirror symmetrical. Furthermore, by rotating one of the side sides B1 around the central axis of the reflective structure 30, the side surface of the reflective structure 30 can be obtained.

[0073] In some embodiments, the light guide substrate 10 includes a first body portion 11 and a second body portion 12. The first body portion 11 has a groove surrounding the reflective structure 30, with the opening of the groove facing the light-emitting device 21. The second body portion 12 is filled in the groove. The second body portion 12 has the same refractive index as the first body portion 11. It should be noted that the same refractive index between the second body portion 12 and the first body portion 11 means that their refractive indices can be approximately the same (e.g., the difference between their refractive indices does not exceed 0.1), or they can have completely identical refractive indices.

[0074] For example, the material of the first body part 11 includes glass, and the material of the second body part 12 includes any one of polymethyl methacrylate (PMMA), polycarbonate (PC), cyclic polyolefin (COP), cyclic olefin copolymer (COC), MS (methyl methacrylate-styrene copolymer) resin, and nanocomposite materials.

[0075] For example, the first body portion 11 includes a first sub-body portion and a second sub-body portion stacked together. The first sub-body portion and the second sub-body portion have the same or approximately the same refractive index. The material of the first sub-body portion includes glass, and the material of the second sub-body portion includes any one of polymethyl methacrylate (PMMA), polycarbonate (PC), cyclic polyolefin (COP), cyclic olefin copolymer (COC), MS (methyl methacrylate-styrene copolymer) resin, and nanocomposite materials.

[0076] In some embodiments, the reflective structure 30 includes a main body 31 and a first reflective layer 32 located on the side of the main body 31. The main body 31 and the first body 11 are an integral structure. Along the direction away from the light-emitting component 20, the cross-section of the main body 31 parallel to the first bottom surface 101 gradually increases.

[0077] Figure 4 This is a schematic diagram illustrating the process of forming a reflective structure 30 within a light guide substrate 10, as provided in some embodiments of this disclosure. Figure 5 This is another schematic diagram illustrating the process of forming a reflective structure 30 within a light guide substrate 10, as provided in some embodiments of this disclosure, such as... Figure 4 and Figure 5 As shown, in the fabrication process, a first region of the light guide plate body 10a can be partially etched to form a groove V1. The portion of the first region that is not etched away serves as the main body 31 of the reflective structure 30. Then, a first reflective layer 32 is formed on the side surface of the second body 12. The material of the first reflective layer 32 can be a metal material with high reflectivity, such as silver. Afterward, the second body 12 is filled into the groove V1. The thickness of the first reflective layer 32 can be uniformly distributed.

[0078] During the etching of the light guide plate body 10a, lateral etching and longitudinal etching at similar or equal rates occur simultaneously. Therefore, in the main body 31 of the reflective structure 30, the two sides of the longitudinal section extending along its central axis are mirror-symmetrical and both are concave arc-shaped edges. In other words, after the formation of the first reflective layer 32, the two sides B1 of the first longitudinal section M1 of the entire reflective structure 30 are mirror-symmetrical and both are concave arc-shaped edges. Taking the example of the same lateral and longitudinal etching rates, both sides B1 are arc-shaped. Furthermore, when the etching radius is the same as the radius of the orthographic projection of the main body 31 of the reflective structure 30 onto the first bottom surface (e.g., ...), ... Figure 4 As shown), after etching, a conical main body 31 is formed, and the tip of the main body 31 is flush with the first top surface of the light guide substrate 10. When the etching radius is greater than the radius of the main body 31 of the reflective structure 30 (e.g., Figure 5As shown), after etching, a conical main structure is formed. The height of the conical structure is less than the etching radius (which is also the etching depth). In this case, after forming the main body 31, the light guide plate body can be thinned so that the tip of the main body 31 is approximately flush with the surface of the light guide plate body facing the light-emitting component 20. The thinned light guide plate body serves as the first body 11 of the light guide substrate 10. After the thinning process, the second body 12 can be filled into the groove V1. Through the thinning process, the light-emitting surface of the light-emitting component 20 can be brought as close as possible to the reflective structure 30, thereby increasing the upper limit of the length of the third reference line segment L3 while keeping the length of the bottom edge B0 of the first longitudinal section M1 constant.

[0079] In some embodiments, such as Figure 2 As shown, the light-emitting substrate further includes a first filling layer 70, which is located between the light-emitting surface and the light guide substrate 10. The first filling layer 70 contacts both the light-emitting surface of the light-emitting component 20 and the light guide substrate 10. The refractive index of the material of the first filling layer 70 is similar to that of the material of the light guide substrate 10; for example, the difference between their refractive indices is less than or equal to 0.1. In one example, the refractive index of the material of the light guide substrate 10 is 1.5, and the refractive index of the material of the first filling layer 70 is between 1.4 and 1.6. For example, the material of the first filling layer 70 is any one of polymethyl methacrylate (PMMA), polycarbonate (PC), cyclic polyolefin (COP), cyclic olefin copolymer (COC), MS (methyl methacrylate-styrene copolymer) resin, or nanocomposite materials.

[0080] In some embodiments, the two ends of the third reference line segment L3 are in contact with the first reference line segment L1 and the second reference line segment L2, respectively, which helps to increase the light-emitting area of ​​the light-emitting component 20 and improve the light efficiency.

[0081] For example, the refractive index of the material of the first filling layer 70 is the same as that of the material of the light guide substrate 10, and the two ends of the third reference line segment L3 are in contact with the first reference line segment L1 and the second reference line segment L2 respectively, thereby reducing direct light leakage and maximizing the light efficiency of the light-emitting component 20.

[0082] For example, the light-emitting surface of the light-emitting component 20 is rectangular, with its long side parallel to the first longitudinal section M1; or, its short side parallel to the first longitudinal section M1; or, its diagonal parallel to the first longitudinal section M1. When the diagonal of the light-emitting surface is parallel to the first longitudinal section M1, and the refractive index of the material of the first filling layer 70 is the same as that of the material of the light guide substrate 10, and the two ends of the third reference line segment L3 are in contact with the first reference line segment L1 and the second reference line segment L2 respectively, it can be ensured that all light rays emitted from the light-emitting surface will not experience direct light leakage, while maximizing the light-emitting area of ​​the light-emitting component 20.

[0083] Among these requirements, when the third reference segment L3 is located within the first triangle △abc, and the length of the base B0 of the first longitudinal section M1 (i.e., the diameter of the reflective structure 30) is constant, the smaller the placement height of the light-emitting surface (i.e., the minimum vertical distance between the light-emitting surface and the reflective structure 30), the larger the upper limit of the size of the light-emitting surface. For example, if the material of the first filling layer 70 has the same refractive index as the material of the light guide substrate 10, then when the placement height of the light-emitting surface is 10 micrometers, and the diameter of the reflective structure 30 is 400 micrometers, the upper limit of the length of the third reference segment L3 is 10.9 micrometers. That is, the length of the third reference segment L3 needs to be less than or equal to 10.9 micrometers. To increase the length of the third reference segment L3, the height of the reflective structure 30 can be reduced, and the placement height of the light-emitting surface can be reduced through the aforementioned thinning process.

[0084] In other embodiments, such as Figure 3 As shown, the light guide substrate 10 also includes a first top surface facing the light-emitting component 20. A first reference line segment L1 intersects the first top surface at a third endpoint b', and a second reference line segment L2 intersects the first top surface at a fourth endpoint c'. The line connecting the third endpoint b' and the fourth endpoint c' is the fourth reference line segment. A first filling layer 70 exists between the light-emitting surface and the light guide substrate 10. The refractive index of the first filling layer 70 is n2, and the refractive index of the light guide substrate 10 is n1; 1 < n2 ≤ n1.

[0085] exist Figure 3 In the illustrated embodiment, the triangle principle that the light-emitting surface must satisfy also includes the following condition two: the fourth reference line segment, the fifth reference line segment L5, and the sixth reference line segment L6 form a second triangle △a'b'c', the second triangle △a'b'c' is located inside the first triangle △abc, the fifth reference line segment L5 passes through the third endpoint b', and the angle between the fifth reference line segment L5 and the fourth reference line segment is the refraction angle when light enters the first filling layer 70 from the light guide substrate 10 along the first reference line segment L1, that is, The sixth reference line segment L6 passes through the fourth endpoint c', and the angle between the sixth reference line segment L6 and the fourth reference line segment is the refraction angle when light rays along the second reference line segment L2 enter the first filling layer 70 from the light guide substrate 10, that is, A1 is the first included angle, A2 is the second included angle, and the third reference line segment L3 is located inside the second triangle △a'b'c'.

[0086] When the light-emitting surface meets the above condition 2, the problem of direct light leakage can still be reduced even when there is a first filling layer 70 between the light-emitting surface and the light guide substrate 10.

[0087] For example, the light-emitting surface of the light-emitting component 20 is rectangular, with its long side parallel to the first longitudinal section M1; or, its short side parallel to the first longitudinal section M1; or, its diagonal parallel to the first longitudinal section M1. When the diagonal of the light-emitting surface is parallel to the first longitudinal section M1, and the third reference line segment L3 is located within the second triangle △a'b'c', it can be ensured that all light rays emitted from the light-emitting surface will not experience direct light leakage.

[0088] Preferred, in Figure 3 In the embodiment shown, the two ends of the third reference line segment L3 are in contact with the fifth reference line segment L5 and the sixth reference line segment L6, respectively. This reduces or prevents direct light leakage while increasing the light-emitting area of ​​the light-emitting component 20 and improving the light efficiency.

[0089] Figure 6 Here are two optical path diagrams provided in some embodiments of this disclosure, showing the light being reflected once by the reflecting structure 30, such as... Figure 6 As shown, the first longitudinal section M1 also includes two side edges B1 connected to the two ends of the bottom edge B0, respectively. The two side edges B1 are located on opposite sides of the central axis of the reflective structure 30, and the two ends of the third reference line segment L3 are located on opposite sides of the central axis of the reflective structure 30. For example, the two side edges B1 of the first longitudinal section M1 are arc-shaped and concave towards the central axis of the reflective structure 30, and the overall shape of the reflective structure 30 is a cone or frustum with concave sides.

[0090] In some embodiments, a first reflection point d exists on side B1. The first reflection point d is a reflection point capable of reflecting light rays from the end of the third reference line segment L3 to the outside of side B1. In other words, the first reflection point d is used to reflect the first light rays from the corresponding end of the third reference line segment L3 toward the first reflection point d in a direction away from side B1. At least one first reflection point d satisfies a first preset condition, which includes: β+2γ is greater than or equal to the largest of the first included angle and the second included angle.

[0091] Where γ = arctan k, k is the slope of the tangent at the first reflection point d; β is the angle between the incident direction of the first ray when it is incident on the first reflection point d and the thickness direction of the light guide substrate 10. When the distance from the end of the third reference line segment L3 to the central axis of the reflective structure 30 is greater than the distance from the first reflection point d to the central axis of the reflective structure 30, β takes a negative value; when the distance from the end of the third reference line segment L3 to the central axis of the reflective structure 30 is less than the distance from the first reflection point to the central axis of the reflective structure 30, β takes a positive value.

[0092] exist Figure 6 Figure (a) shows the reflected light path when β > 0. Figure 6Figure (b) shows the reflected light path diagram when β < 0. According to mathematical geometry, the slope k of the tangent at the first reflection point d and its corresponding γ satisfy formula (1). γ is the acute angle between the tangent at the first reflection point d and the first bottom surface, which is also the angle between the normal at the first reflection point d and the thickness direction of the light guide substrate 10.

[0093] γ=arctan k (1)

[0094] According to the law of light propagation, the angles θ and γ between the reflected light at the first reflection point d and the thickness direction of the light guide substrate 10 satisfy formula (2):

[0095] θ=β+2γ (2)

[0096] θ can also be regarded as the incident angle of the reflected light at the first reflection point d when it hits the first top surface. When β+2γ is greater than or equal to the largest of the first and second included angles, it means that after the light at the end of the third reference line segment L3 is reflected at the first reflection point d, the incident angle of the reflected light at the first top surface is greater than or equal to the critical angle of total internal reflection. In this case, when the light at any other position other than the upper end of the third reference line segment L3 is reflected at the first reflection point d, the reflected light can undergo total internal reflection within the light guide substrate 10.

[0097] In one example, there are multiple first reflection points d on the side B1. The curvature of the side B1 of the first longitudinal section M1 can be set so that each first reflection point d on the side B1 satisfies the above-mentioned first preset condition, thereby ensuring that after the light at any position on the third reference line segment L3 is reflected once by the reflection structure 30, the reflected light can still undergo total internal reflection within the light guide substrate 10.

[0098] Figure 7 Here are two optical path diagrams provided in some embodiments of this disclosure, showing that light is reflected twice by the reflecting structure 30, such as... Figure 7 As shown, the first longitudinal section M1 also includes two side edges connected to the two ends of the bottom edge B0, respectively. The two side edges B1 are located on opposite sides of the central axis of the reflective structure 30, and the two ends of the third reference line segment L3 are located on opposite sides of the central axis of the reflective structure 30. For example, the two side edges B1 of the first longitudinal section M1 are arc-shaped and concave towards the central axis of the reflective structure 30, and the overall shape of the reflective structure 30 is a cone or frustum with concave sides.

[0099] In some embodiments, a second reflection point e and a third reflection point f are present on the side. A second ray of light emitted from the end of the third reference line segment L3 near the second reflection point e can be reflected by the second reflection point e to the third reflection point f, and then reflected by the third reflection point f in a direction away from the side B1. That is, the ray emitted from the end position of the second reference line segment L2 can undergo two reflections on the reflective structure 30 and then be reflected in a direction away from the side of the reflective structure 30, with the two reflection positions being the second reflection point e and the third reflection point f, respectively.

[0100] Wherein, at least one second reflection point e satisfies a second preset condition, the second preset condition including: (2C+2)γ1-(2C+1)|β'|-180C is greater than the largest of the first included angle and the second included angle. Wherein, γ1 is the acute angle between the tangent of the second reflection point e and the bottom edge B0; |β'| is the absolute value of the angle between the incident direction of the second light ray when it is incident on the second reflection point e and the thickness direction of the light guide substrate 10; C is a constant related to β' and γ1.

[0101] exist Figure 7 Figure (a) shows the reflected light path when β' > 0. Figure 7 Figure (b) illustrates the reflected ray path when β' < 0, where the tangent slope k1 at the second reflection point e still satisfies γ1 = arctank1. The reflection angle corresponding to the reflected ray at the second reflection point e is... The central angle corresponding to the chord formed between the second reflection point e and the third reflection point f is Ω, and the angle between the line connecting the third reflection point f to the center of the circle and the perpendicular direction is γ1'. Based on the geometric triangle relationship, the following formula can be derived:

[0102]

[0103] in, Let be the reflection angle of the reflected light rays at the second reflection point e and the third reflection point f. fix() indicates rounding down the result. According to the relationship between k1 and γ1, and formulas (3) to (6), the expression for the reflection angle θ' can be obtained by solving it together as formula (7):

[0104] θ'=(2C+2)γ1-(2C+1)|β'|-180C (7)

[0105] Where C is a constant determined by γ1 and β'. θ' is the angle between the reflected ray from the third reflection point f and the thickness direction of the light guide substrate, which can also be regarded as the incident angle of the reflected ray at the third reflection point f when it hits the first top surface. When the second reflection point e satisfies the second preset condition, the light ray at the end of the third reference line segment L3 is reflected by the second reflection point e and the third reflection point f in sequence. The incident angle of the reflected ray at the first top surface is greater than or equal to the critical angle of total internal reflection. In this case, when the light ray at any other position other than the upper end of the third reference line segment L3 is reflected by the second reflection point e and the third reflection point f, the reflected ray can undergo total internal reflection within the light guide substrate.

[0106] In one example, there are multiple second reflection points e and multiple third reflection points f on the side. The curvature of the side of the first longitudinal section M1 can be set so that each second reflection point e on the side satisfies the above-mentioned second preset condition, thereby ensuring that after the light at any position on the third reference line segment L3 is reflected twice by the reflection structure 30, the reflected light can still undergo total internal reflection within the light guide substrate.

[0107] In some embodiments, the light guide substrate 10 and the reflective structure 30 are transmitted via... Figure 4 or Figure 5 The process is as follows: the first longitudinal section M1 is prepared by adding two side edges connected to both ends of the bottom edge B0. Both side edges are concave arc-shaped edges and are symmetrically arranged about the central axis of the reflective structure 30. Furthermore, the height of the light-emitting surface is set at the top of the reflective structure 30, meaning the end of the reflective structure 30 near the light-emitting component 20 is approximately flush with the first top surface. This reduces the height of the light-emitting surface, thereby increasing its area. Here, "approximately flush" means that the vertical distance between the end of the reflective structure 30 near the light-emitting component 20 and the first top surface is less than or equal to 1 / 10 of the height of the reflective structure 30.

[0108] In some embodiments, a light-collecting structure may be provided on the light guide substrate 10 outside the area where the reflective structure 30 is located, while no light-collecting structure may be provided on the light guide substrate 10 in the area where the reflective structure 30 is located. To avoid the problem of low brightness of the light-emitting substrate in the area where the reflective structure 30 is located due to the lack of a light-collecting structure, in some examples, the length of the bottom edge B0 of the first longitudinal section M1 (e.g., Figure 8 The W0 indicated in the figure is less than 110 micrometers, that is, the diameter of the reflective structure 30 is less than 110 micrometers. At this time, the brightness difference between the area where the reflective structure 30 is located and other areas is less than 20%, and the human eye will not see obvious brightness difference when viewing it at close range.

[0109] Figure 9This is a data diagram showing the relevant parameters of the light-emitting component 20 when the diameter of the reflective structure 30 is 110 micrometers. When acquiring these parameters, both sides of the first longitudinal section M1 are concave arc-shaped edges, symmetrically arranged about the central axis of the reflective structure 30. Furthermore, the vertical distance between the end of the reflective structure 30 near the light-emitting component 20 and the first top surface is less than or equal to the height of the reflective structure 30 (e.g., ...). Figure 8 1 / 10 of h0 (identified in the middle). Figure 9 In this context, the maximum length of the third reference segment L3 allowed by the triangle represents the maximum length that the third reference segment L3 can achieve when the light-emitting surface satisfies the aforementioned "triangle principle." The maximum length of the third reference segment L3 determined by the etching radius represents the maximum length that the third reference segment L3 can achieve when the light from the end of the third reference segment L3 is reflected by the side of the first longitudinal section M1, and the angle between the reflected light and the thickness direction of the light guide substrate 10 is greater than or equal to the first angle and the second angle. There is a certain discrepancy between "the maximum length of the third reference segment L3 allowed by the triangle" and "the maximum length of the third reference segment L3 determined by the etching radius."

[0110] pass Figure 9 It can be seen that the deeper the etching depth, the lower the height of the reflective structure 30, and the smaller the angle between the reflected light from the light-emitting surface and the thickness direction of the light guide substrate 10. The size of the light-emitting surface (expressed by the length of the third reference line segment L3) increases with the etching depth, but the rate of increase is slow. When the etching depth reaches 295 micrometers (the process limit), the length of the third reference line segment L3 can reach a maximum of 54 micrometers. The thickness to be reduced in the thinning process is approximately 290 micrometers, and the height of the reflective structure 30 is approximately 5.2 micrometers.

[0111] according to Figure 9 In one example, the length of the bottom edge B0 of the first longitudinal section M1 is less than or equal to 110 micrometers. The vertical distance between the end of the reflective structure 30 near the light-emitting component 20 and the first top surface is set to be less than or equal to 1 / 10 of the height of the reflective structure 30. In this case, the radius of curvature at each position on each arc edge (i.e. side edge) of the first longitudinal section M1 is between 235 and 295 micrometers, the length of the third reference line segment L3 is less than or equal to 54 micrometers, and the height of the reflective structure 30 is between 5 and 5.2 micrometers. This ensures that the light emitted from the light-emitting surface that is not blocked by the reflective structure 30 and directly hits the first bottom surface 101 can undergo total internal reflection. Furthermore, the light reflected by the reflective structure 30 may also undergo total internal reflection within the light guide substrate 10. At the same time, it prevents the area where the reflective structure 30 is located from having a visible difference in brightness compared to other areas.

[0112] It should be noted that the side of the first longitudinal section M1 is a concave arc-shaped edge. This arc-shaped edge can be circular or elliptical, and the radius of curvature at various points on the arc-shaped edge is between 235 and 295 micrometers. When the arc-shaped edge is circular, the radius of curvature at various points on the arc-shaped edge is equal. Figure 8 The radius of the arc marked R is the radius of the circle in which the arc is located, and this radius is equal to the etching depth and etching radius.

[0113] In another example, when the size of the light-emitting surface is constant, the relevant parameters of the reflective structure 30 can be determined based on the size of the light-emitting surface. For example, when the length of the third reference line segment L3 of the light-emitting surface is 75 micrometers, the diameter of the reflective structure 30 at different heights of the light-emitting surface can be calculated according to the aforementioned triangle principle; when the light-emitting surface is located at the top of the reflective structure 30, the diameter of the reflective structure 30 reaches a minimum of 300 micrometers. Based on this, the size range of the third reference line segment L3 corresponding to the reflective structure 30 with a diameter of 300 micrometers and the thinning thickness in the thinning process are calculated, and the calculation results are as follows: Figure 10 As shown.

[0114] In practical design, when the diameter of the reflective structure 30 is determined, the shape and size of the first triangle △abc can be determined; when the length of the third reference line segment L3 is known, the minimum height of the reflective structure 30 can be calculated based on the first and second preset conditions mentioned above. Figure 11 The solid line in the diagram corresponds to the shape. However, since the length of the third reference line segment L3 is fixed, there is redundancy in the distance between it and the lowest reflective structure 30. Therefore, the height of the reflective structure 30 can be increased until its top is flush with the light-emitting surface, reaching the position of the reflective structure 30 indicated by the dashed line. Thus, for a fixed length of the third reference line segment L3, there exists... Figure 10 The maximum and minimum etching depths shown in (a) ensure that the light rays on the third reference line segment L3 of the corresponding size will not leak directly within the range of the reflective structure 30.

[0115] In the thinning process, there is a direct relationship between the thinning thickness and the etching depth. The difference between the etching depth and the thinning thickness is the height of the reflective structure 30. The maximum etching depth corresponds to the maximum thinning thickness, and the minimum etching depth corresponds to the minimum thinning thickness.

[0116] In one example, given that the length of the third reference segment L3 is determined, it can be based on Figure 10 The results are used to set the relevant parameter dimensions of the reflective structure 30. For example, the vertical distance between the end of the reflective structure 30 near the light-emitting component 20 and the first top surface is less than or equal to the height of the reflective structure 30 (e.g., ...). Figure 8The length of the third reference line segment L3 is between 75 and 85 micrometers, which is 1 / 10 of h0. At this time, the radius of curvature at each position on each arc-shaped edge of the first longitudinal section M1 is between 157.3 and 260 micrometers, the thinning thickness in the thinning process is between 37.3 and 140 micrometers, the length of the bottom edge B0 of the first longitudinal section M1 (i.e., the diameter of the reflective structure 30) is greater than or equal to 300 micrometers, and the height of the reflective structure 30 is between 47.7 and 110 micrometers. When the arc-shaped edge is circular, the radius of curvature at each position on the arc-shaped edge is equal. Figure 8 The radius of the arc, R, is the radius of the circle containing the arc.

[0117] In some embodiments of this disclosure, the light-emitting component 20 may include a light-emitting device 21, with at least a portion of the surface of the light-guiding substrate 10 facing outwards serving as a light-emitting surface. In other embodiments of this disclosure, the light-emitting component 20 may include a light-emitting device 21 and a color conversion unit 22. Figure 12 This is a schematic diagram of the specific structure of the light-emitting substrate provided in some embodiments of this disclosure, such as... Figure 12 As shown, the light-emitting component 20 includes a light-emitting device 21 and a color conversion section 22 located on the side of the light-emitting device 21 facing the light-guiding substrate 10. The light-emitting device 21 is used to emit a first light, which is blue light or ultraviolet light, and the color conversion section 22 is used to convert the first light into white light for emission. The light-emitting surface is the area on the surface of the color conversion section 22 facing the light-guiding substrate 10 from which white light is emitted. For example, if the entire surface of the color conversion section 22 facing the light-guiding substrate 10 is unobstructed, white light can be emitted from all positions on the entire surface; in this case, the light-emitting surface is the entire surface of the color conversion section 22 facing the light-guiding substrate 10. Alternatively, if a portion of the surface of the color conversion section 22 facing the light-guiding substrate 10 is obstructed, while the remaining portion is unobstructed, white light can be emitted towards the light-guiding substrate 10; in this case, the light-emitting surface is the unobstructed area on the surface of the color conversion section 22 facing the light-guiding substrate 10.

[0118] For example, the light-emitting device 21 is an LED (light-emitting diode) device, such as a Mini-LED or Micro-LED device. The color conversion unit 22 includes quantum dot material, phosphor material, or other materials capable of color conversion.

[0119] In a specific example, the light-emitting device 21 includes a light-emitting body 213 and a first electrode 211 and a second electrode 212 electrically connected to the light-emitting body 213. The first electrode 211 and the second electrode 212 are located on the side of the light-emitting body 213 facing the light-guiding substrate 10. The light-emitting body 213 may include a first semiconductor layer, a light-emitting layer and a second semiconductor layer stacked together. One of the first semiconductor layer and the second semiconductor layer is an N-type semiconductor layer and the other is a P-type semiconductor layer. The light-emitting layer is, for example, a quantum well material (MQW) layer.

[0120] Additionally, a driving trace layer may be provided on the side of the light guide substrate 10 facing the light-emitting device 21. This driving trace layer is used to provide driving signals to the light-emitting device 21. The driving trace layer includes a first pad 51 and a second pad 52. The first electrode 211 is electrically connected to the first pad 51, and the second electrode 212 is electrically connected to the second pad 52. Furthermore, a limiting dam 60 may be provided on the side of the light guide substrate 10 facing the light-emitting device 21. The limiting dam 60 has a receiving groove located between the first electrode 211 and the second electrode 212. The color conversion part 22 is located in the receiving groove, and the material of the color conversion part 22 includes quantum dot material.

[0121] For example, the light-emitting device 21 corresponds one-to-one with the limiting dam 60, and the limiting dam 60 corresponding to different light-emitting devices 21 are spaced apart from each other; or, for example, the limiting dam 60 corresponding to multiple light-emitting devices 21 is an integral structure, and the limiting dam 60 has a receiving groove that corresponds one-to-one with the light-emitting device 21.

[0122] In some embodiments, such as Figure 1 and Figure 12 As shown, the light-emitting substrate further includes a second reflective layer 40, which is located on the side of the light guide substrate 10 facing the light-emitting device 21. The light guide substrate 10 includes a plurality of light-collecting structures 42 adjacent to the second reflective layer 40, wherein the light-collecting structure 42 includes a reflective surface protruding toward or away from the first bottom surface 101; or, the light-collecting structure 42 is used to scatter light. Through the reflection or scattering effect of the light-collecting structure 42, the light propagating by total internal reflection in the light guide substrate 10 can change its direction after irradiating the light-collecting structure 42, and then exit the light guide substrate 10 from the first bottom surface 101.

[0123] In one example, such as Figure 12 As shown, the light-collecting structure 42 is a recessed structure located on the side of the light guide substrate 10 away from the first bottom surface 101. The inner surface of the recessed structure protrudes towards the first bottom surface 101, and a portion of the second reflective layer 40 is located in the recessed structure and is attached to the inner surface of the recessed structure. In this case, when light from inside the light guide substrate 10 shines on the recessed structure, it will be reflected at the curved surface of the recessed structure.

[0124] In another example, the light-collecting structure 42 is a raised structure located on the side of the light guide substrate 10 away from the first bottom surface 101. The surface of the raised structure protrudes in a direction away from the first bottom surface 101 and is attached to the second reflective layer 40. In this case, when light from inside the light guide substrate 10 shines on the raised surface of the raised structure, it will be reflected at the location of the raised surface.

[0125] In another example, the light guide substrate 10 has multiple recessed structures on the side away from the first bottom surface 101. The recessed structures are filled with a scattering material, and the light-collecting structure 42 includes the recessed structures and the scattering material within the recessed structures. When light shines into the interior of the recessed structures, it is scattered by the scattering material.

[0126] For example, the orthographic projection of the light-collecting structure 42 on the first bottom surface 101 does not overlap with the orthographic projection of the reflective structure 30 on the first bottom surface 101; the orthographic projections of different light-collecting structures 42 on the first bottom surface 101 do not overlap.

[0127] In some embodiments, the maximum feature size of the orthographic projection of the light-collecting structure 42 on the first bottom surface is D, the height of the light-collecting structure 42 is H, and the D / H ratio is between 0.5 and 4.7, so that the light-collecting angle spectrum of the light guide substrate 10 can achieve Gaussian-like extraction. For example, D / H is between 2 and 3, or between 3 and 4, or between 4 and 4.7.

[0128] It should be noted that the shape of the orthographic projection of the light-collecting structure 42 on the first bottom surface 101 can be a triangle, a rectangle, a circle, an ellipse, or other shapes; the aforementioned maximum feature size D refers to the maximum value of the dimensions of the orthographic projection of the light-collecting structure 42 in multiple directions parallel to the first bottom surface 101; for example, if the orthographic projection of the light-collecting structure 42 is a triangle, then the maximum feature size D is the maximum side length of the triangle; for another example, if the orthographic projection of the light-collecting structure 42 is a rectangle, then the maximum feature size D is the maximum value of the two diagonals of the rectangle; for another example, if the orthographic projection of the light-collecting structure 42 is a circle, then the maximum feature size D is the diameter of the circle; for another example, if the light-collecting structure 42 is an ellipse, then the maximum feature size D is the length of the major axis of the ellipse.

[0129] It should also be noted that the overall shape of the light-collecting structure 42 can be a pyramid, a prism, a hemisphere, etc. For example, if the overall shape of the light-collecting structure 42 is prism, its longitudinal section perpendicular to the first base surface 101 can be rectangular; if the overall shape of the light-collecting structure 42 is pyramid, its longitudinal section perpendicular to the first base surface 101 is triangular; if the overall shape of the light-collecting structure 42 is hemisphere, its longitudinal section perpendicular to the first base surface 101 is semicircular or arc-shaped. The height of the light-collecting structure 42 refers to the vertical distance between the end of the light-collecting structure 42 closest to the first base surface 101 and the end furthest from the first base surface 101. When the light-collecting structure 42 includes a protruding structure, the height of the light-collecting structure 42 is the vertical distance between the vertex of the protruding structure furthest from the first base surface 101 and the first top surface; when the light-collecting structure 42 includes a recessed structure, the height of the light-collecting structure 42 is the vertical distance between the bottom point of the recessed structure closest to the first base surface 101 and the first top surface.

[0130] In addition, in the above example, the light-collecting structure 42 can be a recessed structure or a raised structure on the light guide substrate 10, and the second reflective layer 40 is in contact with the surface of the recessed structure or the raised structure of the light-collecting structure 42; or the light-collecting structure 42 can include a recessed structure on the light guide substrate 10 and a scattering material located in the recessed structure. In all these cases, the light-collecting structure can satisfy the above-mentioned D / H range.

[0131] For example, the D / H ratio of light-collecting structure 42 is 4.7.

[0132] In one example, the material is the same at all locations of the first body portion 11. For example, the material of the first body portion 11 includes glass, and the light-collecting structure 42 can be disposed on the first body portion 11. In another example, as described above, the first body portion 11 may include a first sub-body portion and a second sub-body portion stacked together. The materials of the first sub-body portion and the second sub-body portion may be different. In this case, the light-collecting structure 42 can be disposed on the second sub-body portion. For example, the material of the first sub-body portion includes glass, and the material of the second sub-body portion may be the same as the material of the first filling layer 70.

[0133] In some embodiments, such as Figure 12 As shown, the light-emitting substrate also includes a third reflective layer 80, at least a portion of which is located on the side of the light-emitting component 20 away from the light guide substrate 10. By providing the third reflective layer 80, the light from the light-emitting component 20 can be reflected towards the light guide substrate 10, thereby improving light utilization.

[0134] For example, a first portion of the third reflective layer 80 is located on the side of the light-emitting component 20 away from the light guide substrate 10, and a second portion is located between adjacent light-emitting components 20.

[0135] This disclosure also provides a display module, including the light-emitting substrate of any of the above embodiments. Multiple light-emitting components are arranged in an array on a light guide substrate. Additionally, the display module includes a liquid crystal display panel located on the side of the light guide substrate away from the light-emitting components. The light-emitting substrate provides backlighting for the liquid crystal display panel.

[0136] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of this disclosure, and this disclosure is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and substance of this disclosure, and these modifications and improvements are also considered to be within the scope of protection of this disclosure.

Claims

1. A light-emitting substrate, characterized in that, include: Light guide substrate; A light-emitting component is disposed on one side of the light guide substrate, the light-emitting component including a light-emitting surface facing the light guide substrate; The light guide substrate includes a first bottom surface that is away from the light-emitting device; The light guide substrate has a reflective structure inside. Along the direction away from the light-emitting component, the cross-section of the reflective structure parallel to the first bottom surface gradually increases. The side of the reflective structure is used to reflect the light emitted from the light-emitting surface. The reflective structure has a first longitudinal section passing through its central axis. The first longitudinal section includes a bottom edge away from the light-emitting component. The bottom edge includes a first endpoint and a second endpoint. The bottom edge, together with a first reference line segment and a second reference line segment, forms a first triangle. The first reference line segment and the second reference line segment are both located on the side of the straight line containing the bottom edge away from the first bottom surface. The first reference line segment passes through the first endpoint and forms a first angle with the bottom edge. The second reference line segment passes through the second endpoint and forms a second angle with the bottom edge. Both the first angle and the second angle are between 47° and 52°. The first longitudinal section is located within the first triangle, and the light-emitting surface intersects the plane containing the first longitudinal section at a third reference line segment, which is located within the first triangle.

2. The light-emitting substrate according to claim 1, characterized in that, The two ends of the third reference line segment are in contact with the first reference line segment and the second reference line segment, respectively.

3. The light-emitting substrate according to claim 1, characterized in that, The light-emitting substrate further includes a first filling layer, which is located between the light-emitting surface and the light-guiding substrate, and the first filling layer is in contact with the light-emitting surface of the light-emitting component and the light-guiding substrate respectively. The material of the first filler layer includes one of polymethyl methacrylate, polycarbonate, cyclic polyolefin, cyclic olefin copolymer, methyl methacrylate-styrene copolymer, and nanocomposite materials.

4. The light-emitting substrate according to claim 1, characterized in that, The light guide substrate further includes a first top surface facing the light-emitting component, the first reference line segment intersects the first top surface at a third endpoint, the second reference line segment intersects the first top surface at a fourth endpoint, and the line connecting the third endpoint and the fourth endpoint is the fourth reference line segment; A first filling layer exists between the light-emitting surface and the light guide substrate. The refractive index of the first filling layer is n2, and the refractive index of the light guide substrate is n1; 1 < n2 ≤ n1. The fourth reference line segment, together with the fifth and sixth reference line segments, forms a second triangle, which is located within the first triangle. The fifth reference line segment passes through the third endpoint and forms an angle with the fourth reference line segment. The sixth reference line segment passes through the fourth endpoint and forms an angle with the fourth reference line segment. A1 is the first included angle, and A2 is the second included angle; The third reference line segment is located inside the second triangle.

5. The light-emitting substrate according to any one of claims 1-4, characterized in that, The light-emitting component includes a light-emitting device and a color conversion section located on the side of the light-emitting device facing the light guide substrate. The light-emitting device is used to emit a first light, which is blue light or ultraviolet light, and the color conversion section is used to convert the first light into white light for emission. The light-emitting surface is the area on the surface of the color conversion section facing the light guide substrate from which the white light is emitted.

6. The light-emitting substrate according to claim 5, characterized in that, The light-emitting device includes: a light-emitting body and a first electrode and a second electrode electrically connected to the light-emitting body, wherein the first electrode and the second electrode are located on the side of the light-emitting body facing the light guide substrate; The light guide substrate is further provided with a first pad, a second pad, and a limiting dam on the side facing the light-emitting device. The first electrode is electrically connected to the first pad, and the second electrode is electrically connected to the second pad. The defined dam has a receiving groove, which is located between the first electrode and the second electrode, and the color conversion part is located in the receiving groove.

7. The light-emitting substrate according to any one of claims 1-4, characterized in that, The first longitudinal section also includes two side edges connected to the two ends of the bottom edge, the two side edges being located on opposite sides of the central axis of the reflective structure, and the two ends of the third reference line segment being located on opposite sides of the reflective central structure; a first reflection point exists on the side edge, the first reflection point being able to reflect the first light ray incident on the corresponding end of the third reference line segment toward the first reflection point in a direction away from the side edge, wherein at least one of the first reflection points satisfies a first preset condition, the first preset condition being: β+2γ is greater than or equal to the largest of the first included angle and the second included angle; Where γ = arctan k, k is the slope of the tangent at the first reflection point; β is the angle between the incident direction of the first ray when it strikes the first reflection point and the thickness direction of the light guide substrate. When the distance from the end of the third reference line segment to the central axis of the reflective structure is greater than the distance from the first reflection point to the central axis of the reflective structure, β takes a negative value; when the distance from the end of the third reference line segment to the central axis of the reflective structure is less than the distance from the first reflection point to the central axis of the reflective structure, β takes a positive value.

8. The light-emitting substrate according to claim 7, characterized in that, There are multiple first reflection points on the side, and each of the first reflection points satisfies the first preset condition.

9. The light-emitting substrate according to any one of claims 1-4, characterized in that, The first longitudinal section also includes two side sides that are respectively connected to the two ends of the bottom edge. The two side sides are respectively located on opposite sides of the central axis of the reflective structure. The two ends of the third reference line segment are respectively located on opposite sides of the reflective central structure. There are a second reflection point and a third reflection point on the side. The second light ray that is directed toward the second reflection point from the end of the third reference line segment near the second reflection point can be reflected by the second reflection point to the third reflection point and reflected by the third reflection point in a direction away from the side. At least one of the second reflection points satisfies a second preset condition. The second preset condition includes: (2C+2)γ1-(2C+1)|β'|-180C is greater than or equal to the largest of the first included angle and the second included angle. Wherein, γ1 is the acute angle between the tangent of the second reflection point and the bottom edge; |β'| is the absolute value of the angle between the incident direction of the second ray when it is incident on the second reflection point and the thickness direction of the light guide substrate; C is a constant related to β' and γ1.

10. The light-emitting substrate according to claim 9, characterized in that, There are multiple second reflection points and multiple third reflection points on the side, and each second reflection point satisfies the second preset condition.

11. The light-emitting substrate according to any one of claims 1-4, characterized in that, The light guide substrate further includes a first top surface facing the light-emitting component, and the vertical distance between the end of the reflective structure near the light-emitting component and the first top surface is less than or equal to 1 / 10 of the height of the reflective structure. The first longitudinal section also includes two side edges that are respectively connected to the two ends of the bottom edge. The two side edges are concave arc-shaped edges and are symmetrically arranged about the central axis of the reflective structure.

12. The light-emitting substrate according to claim 11, characterized in that, The length of the bottom edge of the first longitudinal section is less than or equal to 110 micrometers; the radius of curvature at each position on the arc edge of the first longitudinal section is between 235 and 295 micrometers; the length of the third reference line segment is less than or equal to 54 micrometers; and the height of the reflective structure is between 5 and 5.2 micrometers.

13. The light-emitting substrate according to claim 11, characterized in that, The length of the third reference line segment is between 75 and 85 micrometers; The radius of curvature at various positions on the arc-shaped edge of the first longitudinal section is between 157.3 and 260 micrometers, and the length of the bottom edge of the first longitudinal section is greater than or equal to 300 micrometers; the height of the reflective structure is between 47.7 and 110 micrometers.

14. The light-emitting substrate according to any one of claims 1-4, characterized in that, The light guide substrate includes: A first body portion, wherein the first body portion has a groove surrounding the reflective structure, and the opening of the groove faces the light-emitting device; The second body portion is filled in the groove; The second body portion has the same refractive index as the first body portion.

15. The light-emitting substrate according to claim 14, characterized in that, The reflective structure includes a main body and a first reflective layer located on the side of the main body. The main body and the first body are an integral structure. Along the direction away from the light-emitting component, the cross-section of the main body parallel to the first bottom surface gradually increases.

16. The light-emitting substrate according to any one of claims 1-4, characterized in that, The light-emitting substrate further includes a second reflective layer, which is located on the side of the light guide substrate facing the light-emitting device; The light guide substrate includes a plurality of light-collecting structures adjacent to the second reflective layer. Each light-collecting structure includes a reflective surface that protrudes toward or away from the first bottom surface; or, the light-collecting structure is used to scatter light.

17. The light-emitting substrate according to claim 16, characterized in that, The maximum feature size of the orthographic projection of the light-collecting structure onto the first bottom surface is D, and the height of the light-collecting structure is H, with D / H ranging from 0.5 to 4.

7.

18. The light-emitting substrate according to claim 16, characterized in that, The light-collecting structure is a recessed structure located on the side of the light guide substrate away from the first bottom surface, and a portion of the second reflective layer is located in the recessed structure and is attached to the inner surface of the recessed structure; Alternatively, the light-collecting structure is a raised structure located on the side of the light guide substrate away from the first bottom surface, and the surface of the raised structure is attached to the second reflective layer; Alternatively, the light-collecting structure may include a recessed structure located on the side of the light guide substrate away from the first bottom surface, and a scattering material filled in the recessed structure.

19. The light-emitting substrate according to any one of claims 1-4, characterized in that, The light-emitting substrate further includes: A third reflective layer, at least a portion of which is located on the side of the light-emitting component away from the light guide substrate.

20. A display module, characterized in that, include: The light-emitting substrate according to any one of claims 1 to 19, wherein the number of light-emitting components is a plurality, and the plurality of light-emitting components are arranged in an array on the light guide substrate; The liquid crystal display panel is located on the side of the light guide substrate away from the light-emitting component.

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