Light-emitting substrate and light-emitting device

Abstract

The utility model provides a light-emitting substrate and light-emitting equipment. The light-emitting substrate comprises a substrate, at least one light-emitting element and a lens structure layer. The at least one light emitting element is located on the substrate. The lens structure layer is located on the side, away from the substrate, of the light-emitting element; the lens structure layer comprises at least one condensing lens structure, and the orthographic projection of each condensing lens structure on the substrate covers the orthographic projection of the light-emitting area of at least one light-emitting element on the substrate; each condensing lens structure comprises at least two lens elements which are arranged in a stacked mode, at least one condensing lens structure comprises a first lens element and a second lens element located on the side, away from the substrate, of the first lens element, and the refractive index of the first lens element is larger than that of the second lens element. A curvature of a surface of the first lens element away from the substrate is less than a curvature of a surface of the second lens element away from the substrate.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and particularly relates to a light-emitting substrate and a light-emitting device. Background Art

[0002] With the development of Micro LED related technologies, they have been widely used in many fields. When Micro LED technology is used in optical devices such as ultraviolet exposure, projectors, and AR glasses, these devices have specific requirements for the angle of the emitted light, and it is required that the light emitted by each light-emitting element in the device has a small divergence angle when exiting. Usually, a lens structure is provided on the light-emitting side of the light-emitting element to reduce the divergence angle of the light.

[0003] In related technologies, in order to make the light-concentrating effect of the lens structure better, the thickness of the lens structure is set to be relatively large, and during the process of preparing the lens structure, it is easy to cause the lens structure to deform, and then cause the emitted light of the light-emitting element to deviate from the desired direction. Summary of the Utility Model

[0004] Embodiments of this application provide a light-emitting substrate and a light-emitting device.

[0005] According to the first aspect of the embodiments of this application, a light-emitting substrate is provided. The light-emitting substrate includes:

[0006] A substrate;

[0007] At least one light-emitting element located on the substrate;

[0008] A lens structure layer located on the side of the light-emitting element away from the substrate; the lens structure layer includes at least one light-concentrating lens structure, and the orthographic projection of each light-concentrating lens structure on the substrate covers the orthographic projection of the light-emitting area of at least one light-emitting element on the substrate; each light-concentrating lens structure includes at least two lens elements stacked, and at least one light-concentrating lens structure includes a first lens element and a second lens element located on the side of the first lens element away from the substrate, the refractive index of the first lens element is greater than that of the second lens element, and the curvature of the surface of the first lens element away from the substrate is less than the curvature of the surface of the second lens element away from the substrate.

[0009] In one embodiment, the lens structure layer includes more than two light-concentrating lens structures, and each light-concentrating lens structure includes the first lens element and the second lens element.

[0010] In one embodiment, at least one of the condenser lens structures includes more than three of the lens elements. Among all the lens elements of the same condenser lens structure, in the direction from the substrate towards the lens structure layer, the curvature of the surface of the lens element away from the substrate gradually increases.

[0011] In one embodiment, at least one of the condenser lens structures includes more than three of the lens elements. Among all the lens elements of the same condenser lens structure, in the direction from the substrate towards the lens structure layer, the refractive index of the lens element gradually decreases.

[0012] In one embodiment, the orthographic projection of each condenser lens structure on the substrate covers the orthographic projection of the light-emitting regions of more than two of the light-emitting elements on the substrate.

[0013] In one embodiment, the light-emitting substrate further includes a filling layer located between the lens structure layer and the substrate, and the filling layer covers each of the light-emitting elements; the lens element in the condenser lens structure that contacts the filling layer is provided independently of the filling layer, or the material of the lens element in the condenser lens structure that contacts the filling layer is the same as the material of the filling layer, and the lens element in the condenser lens structure that contacts the filling layer and the filling layer are integrally formed.

[0014] In one embodiment, the refractive index of the light-emitting element is greater than the refractive index of the filling layer, and the refractive index of the filling layer is greater than or equal to the refractive index of the lens element in the condenser lens structure that contacts the filling layer.

[0015] In one embodiment, the light-emitting substrate further includes a spacer structure located between the lens structure layer and the substrate, and the spacer structure is provided with at least one groove, and each of the light-emitting elements corresponding to one of the condenser lens structures is located in one of the grooves; the material of the spacer structure is a light-absorbing material or a metal.

[0016] In one embodiment, the light-emitting substrate further includes a spacer structure located between the substrate and the lens structure layer, and the spacer structure is provided with at least one groove, and each of the light-emitting elements corresponding to one of the condenser lens structures is located in one of the grooves; the material of the spacer structure is a light-absorbing material or a metal.

[0017] According to a second aspect of the embodiments of the present application, there is provided a light-emitting device, and the light-emitting device includes the above-mentioned light-emitting substrate.

[0018] The light-emitting substrate and the light-emitting device provided by the embodiments of the present application, by setting the refractive index of the first lens element in the condenser lens structure to be greater than that of the second lens element, helps to reduce the difference in refractive index between the condenser lens structure and the adjacent film layer, reduce the amount of total internal reflection that occurs during the propagation of light, and thus helps to increase the light output; the light undergoes at least two refractions when passing through the condenser lens structure, which can further reduce the light exit angle, and can reduce the thickness of the compound lens while ensuring that the divergence angle of the exit light remains unchanged; since the thickness of a single lens element is small, it can avoid the deformation of the lens element during the preparation process of the lens element, which may cause the exit light of the light to deviate from the expected exit direction; by setting the curvature of the surface of the first lens element away from the substrate in at least one condenser lens structure to be less than the curvature of the surface of the second lens element away from the substrate, when the light exit angle of the light is fixed, compared with the solution where the curvature of the surface of the first lens element away from the substrate is equal to the curvature of the surface of the second lens element away from the substrate, the thickness of the condenser lens structure can be reduced, and at the same time, the width of the condenser lens structure in the horizontal direction can be reduced. Furthermore, on the premise that the size of the light-emitting substrate is fixed, more condenser lens structures and light-emitting elements can be arranged, which is beneficial to increasing the light output of the light-emitting substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a partial cross-sectional view of a light-emitting substrate provided by an exemplary embodiment of the present application;

[0020] Figure 2 is a partial cross-sectional view of a light-emitting substrate provided by another exemplary embodiment of the present application;

[0021] Figure 3 is a cross-sectional view of a light-emitting element and a substrate of a light-emitting substrate provided by an exemplary embodiment of the present application;

[0022] Figure 4 is a cross-sectional view of a light-emitting element and a substrate of a light-emitting substrate provided by another exemplary embodiment of the present application;

[0023] Figure 5 is a cross-sectional view of a light-emitting element and a substrate of a light-emitting substrate provided by still another exemplary embodiment of the present application;

[0024] Figure 6 is a partial cross-sectional view of a first intermediate structure provided by an exemplary embodiment of the present application;

[0025] Figure 7 is a partial cross-sectional view of a second intermediate structure provided by an exemplary embodiment of the present application;

[0026] Figure 8 is a partial cross-sectional view of a third intermediate structure provided by an exemplary embodiment of the present application;

[0027] Figure 9 is a partial cross-sectional view of a fourth intermediate structure provided by an exemplary embodiment of the present application;

[0028] Figure 10 is a partial cross-sectional view of a fifth intermediate structure provided by an exemplary embodiment of the present application;

[0029] Figure 11 is a partial cross-sectional view of a sixth intermediate structure provided by an exemplary embodiment of the present application. Specific Embodiment

[0030] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. Without conflict, the embodiments and features in the following embodiments may be combined with each other.

[0031] If there are terms related to directional indication or positional relationship in the embodiments of the present application (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationship and movement conditions between components in a specific posture; if the specific posture changes, the directional indication or positional relationship will also change accordingly. In addition, the terms "first", "second", etc. involved in the embodiments of the present application are only for the purpose of convenient description and cannot be understood as indicating or implying relative importance.

[0032] The embodiments of the present application provide a light-emitting substrate. As Figure 1 and Figure 2 shown, the light-emitting substrate includes a substrate 10, at least one light-emitting element 20, and a lens structure layer 30.

[0033] Each of the light-emitting elements 20 is located on the substrate 10. The lens structure layer 30 is located on a side of each light-emitting element 20 away from the substrate 10; the lens structure layer 30 includes at least one condenser lens structure 301, and a positive projection of each condenser lens structure 301 on the substrate 10 covers a positive projection of a light-emitting area of at least one light-emitting element 20 on the substrate 10. Wherein, the positive projection of the condenser lens structure 301 on the substrate refers to the projection of the condenser lens structure 301 on the substrate 10 when light perpendicular to the substrate 10 irradiates the condenser lens structure 301. Each of the condenser lens structures 301 includes at least two lens elements 31 stacked in a direction away from the substrate 10; at least one of the condenser lens structures 301 includes a first lens element 32 and a second lens element 33 located on a side of the first lens element 32 away from the substrate, and a curvature of a surface of the first lens element 32 away from the substrate 10 is smaller than a curvature of a surface of the second lens element 33 away from the substrate 10.

[0034] In the light-emitting substrate provided by the embodiment of the present application, by setting that the positive projection of each condenser lens structure 301 on the substrate 10 covers the positive projection of the light-emitting area of at least one light-emitting element 20 on the substrate 10, the light emitted by the light-emitting element 20 passes through the condenser lens structure 301 during the propagation process, and the condenser lens structure 301 can reduce the divergence angle of the emitted light; by setting that the refractive index of the first lens element 32 in the condenser lens structure 301 is greater than the refractive index of the second lens element 33, it helps to reduce the difference in refractive index between the condenser lens structure and the adjacent film layer, reduce the amount of total reflection that occurs during the propagation of light, and helps to increase the light output; when the light passes through the condenser lens structure 301, at least two refractions occur, which can further reduce the emission angle of the light, and can reduce the thickness of the compound lens on the premise of ensuring that the divergence angle of the emitted light remains unchanged; since the thickness of a single lens element 31 is small, it can avoid the deformation of the lens element during the preparation process of the lens element 31, which causes the emitted light of the light to deviate from the expected emission direction; by setting that the curvature of the surface of the first lens element 32 away from the substrate 10 in at least one condenser lens structure 301 is smaller than the curvature of the surface of the second lens element 33 away from the substrate 10, when the light output angle of the light is fixed, compared with the case where the curvature of the surface of the first lens element 32 away from the substrate 10 is equal to the curvature of the surface of the second lens element 33 away from the substrate 10, or the curvature of the surface of the first lens element 32 away from the substrate 10 is greater than the curvature of the surface of the second lens element 33 away from the substrate 10, the thickness of the condenser lens structure 301 can be reduced, and at the same time, the width of the condenser lens structure 301 in the horizontal direction can be reduced, so that more condenser lens structures 301 and light-emitting elements 20 can be arranged on the premise that the size of the light-emitting substrate is fixed, which is beneficial to increasing the light output of the light-emitting substrate.

[0035] Among them, the above-mentioned horizontal direction refers to the direction perpendicular to the stacking direction of the film layers in the light-emitting substrate.

[0036] It should be noted that the cross-sectional views provided in the embodiments of the present application are all obtained by cutting the light-emitting substrate along the stacking direction of the film layers in the light-emitting substrate.

[0037] In one embodiment, the surfaces of the lens elements 31 of the condenser lens structure 301 away from the substrate 10 protrude in the direction away from the substrate 10. The surfaces of the lens elements 31 of the condenser lens structure 301 away from the substrate 10 can be a part of a spherical surface or can be an arc surface.

[0038] In one embodiment, as Figure 1 and Figure 2 shown, the lens structure layer 30 includes more than two of the condenser lens structures 301, and each of the condenser lens structures 301 includes the first lens element 32 and the second lens element 33. With such a setting, the width of each condenser lens structure 301 in the horizontal direction is smaller, so that more condenser lens elements 301 and light-emitting elements 20 can be provided on the light-emitting substrate, further effectively improving the light output of the light-emitting substrate.

[0039] In one embodiment, as Figure 2 shown, at least one of the condenser lens structures 301 includes more than three of the lens elements 31. Among all the lens elements 31 of the same condenser lens structure 301, in the direction from the substrate 10 to the lens structure layer 30, the curvature of the surface of the lens element 31 away from the substrate 10 increases in sequence. With such a setting, the thickness of the condenser lens structure 301 and the width of the condenser lens structure 301 in the horizontal direction can both reach the minimum; and the condenser lens structure includes more than three lens elements 31, which can further reduce the divergence angle of the emitted light. Figure 3 In the embodiment shown, the condenser lens structure 301 includes a first lens element 32, a second lens element 33, and a third lens element 34 stacked in the direction from the substrate 10 to the lens structure layer 30. The curvature of the surface of the first lens element 32 away from the substrate 10 is less than the curvature of the surface of the second lens element 33 away from the substrate 10, and the curvature of the surface of the second lens element 33 away from the substrate 10 is less than the curvature of the surface of the third lens element 34 away from the substrate 10. In other embodiments, when the condenser lens structure 301 includes more than three of the lens elements 31, the curvatures of the surfaces of two adjacent lens elements 31 away from the substrate 10 may be the same.

[0040] In one embodiment, as Figure 2As shown, at least one of the condenser lens structures 301 includes more than three lens elements 31. Among all the lens elements 31 of the same condenser lens structure 301, in the direction from the substrate 10 to the lens structure layer 30, the refractive index of the lens element 31 gradually decreases. With such a setting, the condensing effect of the condenser lens structure 301 can be better, reducing the amount of stray light at a large target emission angle; and the difference in refractive index between adjacent lens elements 31 and the difference in refractive index between the condenser lens structure and the adjacent film layer can be further reduced, thereby further reducing the amount of total internal reflection that occurs during the propagation of light. Figure 2 In the embodiment shown, the condenser lens structure 301 includes a first lens element 32, a second lens element 33, and a third lens element 34 stacked in the direction from the substrate 10 to the lens structure layer 30. The refractive index of the first lens element 32 is greater than that of the second lens element 33, and the refractive index of the second lens element 33 is greater than that of the third lens element 34. In other embodiments, when the condenser lens structure 301 includes more than three lens elements 31, the refractive indices of two adjacent lens elements 31 may be the same.

[0041] In one embodiment, as Figure 1 and Figure 2 shown, in each of the condenser lens structures 301, the first lens element 32 is in contact with the second lens element 33, and the second lens element 33 covers the surface of the first lens element 32 away from the substrate 10. With such a setting, the light emitted from the first lens element 32 can all enter the second lens element 33 and be deflected again by the second lens element 33, thereby further reducing the divergence angle of the emission angle.

[0042] In one embodiment, as Figure 1 and Figure 2 shown, the light-emitting substrate further includes a filling layer 50 located between the lens structure layer 30 and the substrate 10, and the filling layer 50 covers each of the light-emitting elements 20. The surface of the filling layer 50 away from the substrate 10 can be a plane, which is convenient for the formation of the lens element in contact with the filling layer 50.

[0043] In one embodiment, as Figure 1 and Figure 2 shown, in each of the condenser lens structures 301, the lens element 31 with the smallest distance from the filling layer 50 is in contact with the filling layer 50. That is, no other film layer is provided between the lens structure layer 30 and the filling layer 50.

[0044] In one embodiment, as Figure 1 and Figure 2As shown, the refractive index of the light-emitting element 20 is greater than that of the filling layer 50, and the refractive index of the filling layer 50 is greater than or equal to the refractive index of the lens element 31 in the condenser lens structure 301 that contacts the filling layer 50. With such a setting, in the direction from the substrate 10 to the lens structure layer 30, the refractive index of the film layer gradually decreases, which helps to reduce the probability of total reflection when the light emitted by the light-emitting material layer 22 passes through the interface between the film layers, and thus can increase the light output.

[0045] In one embodiment, as Figures 1 to 5 shown, the light-emitting element 20 includes a first electrode 21, a semiconductor layer 22, and a second electrode 23. The first electrode 21 and the second electrode 23 are respectively in contact with the semiconductor layer 22. The semiconductor layer 22 includes a first semiconductor layer 221 in contact with the first electrode 21, a second semiconductor layer 222 in contact with the second electrode 23, and a multi-quantum well light-emitting layer 223 located between the first semiconductor layer 221 and the second semiconductor layer 222. When the first electrode 22 is an anode and the second electrode 23 is a cathode, the first semiconductor layer 221 is a P-type semiconductor layer, and the second semiconductor layer 222 is an N-type semiconductor layer. When the first electrode 22 is a cathode and the second electrode 23 is an anode, the first semiconductor layer 221 is an N-type semiconductor layer, and the second semiconductor layer 222 is a P-type semiconductor layer.

[0046] In one embodiment, as Figure 3 shown, the semiconductor layer 22 is located on the side of the first electrode 21 away from the substrate 10, and the second electrode 23 is located on the side of the semiconductor layer 22 away from the substrate 10. When the first electrode 21 is an anode and the second electrode 23 is a cathode, the second electrode 23 of each light-emitting element 20 can be a continuous surface electrode.

[0047] In another embodiment, as Figure 4 shown, a part of the first semiconductor layer 221 extends beyond the multi-quantum well light-emitting layer 223. The first electrode 21 is located on the surface of the part of the first semiconductor layer 221 that extends beyond the multi-quantum well light-emitting layer 223 and is away from the substrate 10, and the second electrode 23 is located on the surface of the second semiconductor layer 222 away from the substrate 10.

[0048] In still another embodiment, as Figure 5 shown, the first semiconductor layer 221 is located on the side of the first electrode 21 away from the substrate 10. A part of the second semiconductor layer 222 extends beyond the multi-quantum well light-emitting layer 223, and the second electrode 23 is located between the part of the second semiconductor layer 222 that extends beyond the multi-quantum well light-emitting layer 223 and the substrate 10.

[0049] In one embodiment, the material of the lens element 31 in the condenser lens structure 301 that contacts the filling layer 50 is the same as that of the filling layer 50 and is integrally formed. With such an arrangement, the refractive index of the lens element 31 in the condenser lens structure 301 that contacts the filling layer 50 is the same as that of the filling layer 50, so that the light emitted by the light-emitting element 20 will not be reflected when passing through the interface between the filling layer 50 and the condenser lens structure 301, which helps to increase the light output of the light-emitting substrate; and during the preparation of the light-emitting substrate, the film layer for forming the lens element 31 that contacts the filling layer 50 can be formed simultaneously with the filling layer 50, which helps to simplify the preparation process.

[0050] In another embodiment, the lens element 31 in the condenser lens structure 301 that contacts the filling layer 50 is independently provided from the filling layer 50. Among them, the fact that the lens element 31 that contacts the filling layer 50 is independently provided from the filling layer 50 means that the two are formed in different process steps.

[0051] In one embodiment, the material of the light-emitting material layer 22 is gallium nitride, and its refractive index is about 2.7. The material of the second electrode 23 can be indium tin oxide, and its refractive index is between 1.8 and 2.1.

[0052] In one embodiment, the material of the first lens element 32 is alumina, and the material of the second lens element 33 is silica. The refractive index of alumina is about 1.76, and the refractive index of silica is about 1.45. The difference between the two is small, and the probability of total reflection of light when passing through the interface between the first lens element 32 and the second lens element 33 is small; and the materials of the first lens element 32 and the second lens element 33 are easy to obtain and the cost is low.

[0053] In one embodiment, as Figure 1 and Figure 2 shown, the light-emitting substrate further includes an isolation structure 40 located between the substrate 10 and the lens structure layer 30. The isolation structure 40 is provided with at least one groove 41, and each of the light-emitting elements 20 corresponding to one condenser lens structure 301 is located in one groove 41; the material of the isolation structure 40 is a light-absorbing material or a metal. The number of grooves 41 and the condenser lens structures 301 can be the same and correspond one by one. The isolation structure 40 can be located on the side of the second electrode 23 away from the substrate 10. By providing the isolation structure 40, among the light emitted by the light-emitting elements 20, the light with a larger emission angle is absorbed by the isolation structure 40 or reflected by the side surface of the groove 41 of the isolation structure 40, which helps to reduce the amount of stray light with a large emission angle; and the isolation structure 40 can prevent crosstalk between the light emitted by the light-emitting elements 20 in different grooves 41. Figure 1 and Figure 2In the illustrated embodiment, a light-emitting element 20 is provided in a groove 41, that is, the orthographic projection of a condenser lens structure 301 on the substrate 10 covers the orthographic projection of the light-emitting area of a light-emitting element 20 on the substrate 10. In other embodiments, two or more light-emitting elements 20 may be provided in a groove 41, that is, the orthographic projection of a condenser lens structure 301 on the substrate 10 covers the orthographic projection of the light-emitting areas of two or more light-emitting elements 20 on the substrate 10.

[0054] Further, the material of the isolation structure 40 is metal, the side surface of the groove 41 is an inclined surface, and the side surfaces of the grooves 41 extend obliquely outward in the direction from the substrate 10 to the lens structure layer 30. Thus, among the light rays emitted by the light-emitting element 20, the light rays with a larger exit angle are reflected by the side surfaces of the grooves 41, and the exit angle of the reflected light rays is reduced, which is beneficial to increasing the amount of light rays with the target divergence angle.

[0055] In one embodiment, when the material of the isolation structure 40 is a light-absorbing material, the material of the isolation structure 40 may include at least one of a black matrix photoresist and polyimide. When the material of the isolation structure 40 is metal, the material of the isolation structure 40 may include at least one of Au, Al, Cu, and Ag.

[0056] In one embodiment, as Figure 1 and Figure 2 shown, the light-emitting element 20 further includes a passivation layer 24 located between the light-emitting material layer 22 and the second electrode 23. The passivation layer 24 covers the side surface of the light-emitting material layer 22 and partially covers the top surface of the light-emitting material layer 22 away from the substrate 10. The passivation layer 24 is provided with an opening 241. The opening 241 exposes a part of the top surface of the light-emitting material layer 22. The second electrode 23 contacts the light-emitting material layer 22 through the opening 241. The opening 241 defines the light-emitting area of the light-emitting element 20. The passivation layer 24 covers the side surface of the first electrode 21, which can prevent the first electrode 21 from being short-circuited with the second electrode 23.

[0057] In one embodiment, the material of the passivation layer 24 includes at least one of silicon oxide, silicon nitride, and aluminum oxide.

[0058] In one embodiment, the substrate 10 is a rigid substrate, and the rigid substrate may be a glass substrate, a quartz substrate, a sapphire substrate, etc.

[0059] The embodiment of the present application further provides a method for manufacturing a light-emitting substrate. Taking the light-emitting substrate shown below as an example, the method for manufacturing the light-emitting substrate will be introduced. Figure 1 shown, the method for manufacturing the light-emitting substrate will be introduced.

[0060] First, a substrate 10 is provided.

[0061] Subsequently, a first electrode 21 is formed on the substrate 10.

[0062] Subsequently, a light-emitting material film layer is formed on the side of the first electrode 21 away from the substrate 10. The light-emitting material film layer is a continuous film layer that can cover the substrate. The light-emitting material film layer is etched to obtain a plurality of spaced-apart light-emitting material layers 22.

[0063] Through this step, the first intermediate structure as shown in Figure 6 can be obtained.

[0064] Subsequently, a passivation layer 24 is formed, and openings 241 are formed in the portions of the passivation layer 24 located on the top surfaces of the respective light-emitting material layers 22.

[0065] Through this step, the second intermediate structure as shown in Figure 7 can be obtained.

[0066] Subsequently, a second electrode 23 is formed. The second electrode covers the passivation layer 24 and fills each of the openings 241 in the passivation layer 24.

[0067] Through this step, the third intermediate structure as shown in Figure 8 can be obtained. As shown in Figure 8 , the second electrodes 23 of the respective light-emitting elements 20 are continuous planar electrodes.

[0068] Subsequently, an isolation structure 40 is formed on the side of the second electrode 23 away from the substrate 10. The isolation structure 40 is provided with a plurality of grooves 41, and each groove 41 is provided with a light-emitting element 20.

[0069] Through this step, the fourth intermediate structure as shown in Figure 9 can be obtained.

[0070] Subsequently, a filling layer 50 is formed.

[0071] Through this step, the fifth intermediate structure as shown in Figure 10 can be obtained. As shown in Figure 10 , the filling layer 50 fills each of the grooves 41 of the isolation structure 40, and the surface of the filling layer 50 away from the substrate is a flat surface.

[0072] Subsequently, a first lens element 32 is formed on the filling layer 50.

[0073] Through this step, the sixth intermediate structure as shown in Figure 11 can be obtained.

[0074] In one embodiment, the step of forming the first lens element 32 on the filling layer 50 may include the following process: First, a first inorganic layer is formed on the filling layer 50. The first inorganic layer may cover the surface of the filling layer 50 away from the substrate 10, and the material of the first inorganic layer may be alumina. Then, photoresist is spin-coated on the surface of the first inorganic layer, and exposure and development are performed to form a plurality of photoresist blocks, with each photoresist block located above a groove 41 of the isolation structure 40. Then, each photoresist block is exposed and developed. By controlling the exposure amount in different regions, the shape of the surface of the photoresist block away from the substrate 10 after development is the same as the shape of the surface of the first lens element 32 away from the substrate. Then, the photoresist is baked to cure it. Then, a dry etching process is used to etch the surface of the photoresist block away from the substrate 10, and the etching rate of each part of the surface of the photoresist block away from the substrate 10 is the same, and the area of the first inorganic layer not covered by the photoresist block is etched simultaneously. During the etching process, after a certain position of the photoresist block is completely etched away, the exposed part of the first inorganic layer starts to be etched. Since the thickness of the photoresist block is not the same in each region, after the photoresist block is completely etched away finally, the etched thicknesses of different regions of the first inorganic layer are not all the same, so that the surfaces of the first lens elements 32 away from the substrate 10 obtained after etching the first inorganic layer are basically the same as the surface shape when the photoresist block is not etched.

[0075] Subsequently, the second lens element 33 is formed.

[0076] Through this step, the following can be obtained as Figure 1The light-emitting substrate shown. The step of forming the second lens element 33 may include the following process: First, a second inorganic layer is formed on the first lens element 32. The second inorganic layer may cover each first lens element 32. The surface of the second inorganic layer away from the substrate 10 is a plane, and the material of the second inorganic layer may be silicon oxide. Then, a photoresist is spin-coated on the surface of the second inorganic layer, and exposure and development are performed to form a plurality of photoresist blocks, with each photoresist block located above one first lens element 32. Then, each photoresist block is exposed and developed, and the exposure amount in different regions is controlled so that the shape of the surface of the photoresist block away from the substrate 10 after development is the same as the shape of the surface of the second lens element 33 away from the substrate. Then, the photoresist is baked to cure it. Then, a dry etching process is used to etch the surface of the photoresist block away from the substrate 10, and the etching rate at each part of the surface of the photoresist block away from the substrate 10 is the same, and the region of the second inorganic layer not covered by the photoresist block is etched simultaneously. During the etching process, after a certain position of the photoresist block is completely etched away, the exposed part of the second inorganic layer starts to be etched. Since the thickness of the photoresist block is not the same in each region, finally, after all the photoresist blocks are etched away, the etched thicknesses of different regions of the second inorganic layer are not the same, so that the surfaces of the second lens elements 33 away from the substrate 10 obtained after etching the second inorganic layer are basically the same as the surface shape when the photoresist blocks are not etched.

[0077] In one embodiment, as Figure 2 shown, when the condenser lens structure includes a third lens element 34 on the side of the second lens element 33 away from the substrate, after the step of forming the second lens element 33, the method for preparing the light-emitting substrate further includes: forming the third lens element 34. The preparation process of the third lens element 34 is similar to the preparation process of the second lens element 33 and will not be elaborated here.

[0078] In one embodiment, when the material of the filling layer 50 is the same as the material of the first lens element 32, the steps of forming the filling layer 50 and forming the first lens element 32 on the filling layer 50 may include the following process:

[0079] First, a filling material layer is formed. The filling material layer fills each groove 41 of the isolation structure 40, and a part of the filling material layer is located on the side of the surface of the isolation structure 40 away from the substrate. The surface of the filling material layer away from the substrate is a flat surface. Then, a photoresist is spin-coated on the surface of the filling material layer, and exposure and development are performed to form a plurality of photoresist blocks, with each photoresist block located above a groove 41 of the isolation structure 40. Then, exposure and development are performed on each photoresist block, and the exposure amount in different regions is controlled so that the shape of the surface of the photoresist block away from the substrate 10 after development is the same as the shape of the surface of the first lens element 32 away from the substrate. Then, the photoresist is baked to cure it. Then, a dry etching process is used to etch the surface of the photoresist block away from the substrate 10, and the etching rate of each part of the surface of the photoresist block away from the substrate 10 is the same, and the area of the filling material layer not covered by the photoresist block is etched simultaneously. During the etching process, after a certain position of the photoresist block is completely etched away, the exposed part of the filling material layer starts to be etched. After all the photoresist blocks are etched away, a part of the thickness of the filling material layer forms the first lens element 32, and the part of the filling material layer located on the side of the first lens element 32 facing the substrate 10 is the filling layer 50.

[0080] An embodiment of the present application further provides a light-emitting device, and the light-emitting device includes the light-emitting substrate described in any of the above embodiments.

[0081] In one embodiment, the light-emitting device further includes a housing, and the light-emitting substrate is embedded in the housing.

[0082] In one embodiment, the light-emitting device is at least one of an ultraviolet exposure device, a projector, and an AR glasses.

[0083] It should be noted that the technical solutions or technical features described in the above embodiments can be combined or supplemented with each other without conflict. The scope of protection of the present application is not limited to the precise structures described in the above embodiments and shown in the drawings; any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the scope of protection of the present application.

Claims

1. A light-emitting substrate, characterized in that, The light-emitting substrate includes: a substrate; at least one light-emitting element located on the substrate; a lens structure layer located on a side of the light-emitting element away from the substrate; the lens structure layer includes at least one condenser lens structure, and a positive projection of each condenser lens structure on the substrate covers a positive projection of a light-emitting area of at least one of the light-emitting elements on the substrate; each of the condenser lens structures includes at least two lens elements stacked, and at least one of the condenser lens structures includes a first lens element and a second lens element located on a side of the first lens element away from the substrate, a refractive index of the first lens element is greater than a refractive index of the second lens element, and a curvature of a surface of the first lens element away from the substrate is less than a curvature of a surface of the second lens element away from the substrate.

2. The light-emitting substrate according to claim 1, wherein The lens structure layer includes more than two of the condenser lens structures, and each of the condenser lens structures includes the first lens element and the second lens element.

3. The light-emitting substrate according to claim 1, wherein At least one of the condenser lens structures includes more than three of the lens elements, and among all the lens elements of the same condenser lens structure, in a direction from the substrate to the lens structure layer, curvatures of surfaces of the lens elements away from the substrate increase in sequence.

4. The light-emitting substrate according to claim 1, wherein At least one of the condenser lens structures includes more than three of the lens elements, and among all the lens elements of the same condenser lens structure, in a direction from the substrate to the lens structure layer, refractive indices of the lens elements gradually decrease.

5. The light-emitting substrate according to claim 1, characterized in that, A positive projection of each condenser lens structure on the substrate covers positive projections of light-emitting areas of more than two of the light-emitting elements on the substrate.

6. The light-emitting substrate according to claim 1, wherein The light-emitting substrate further includes a filling layer located between the lens structure layer and the substrate, and the filling layer covers each of the light-emitting elements; a lens element of the condenser lens structure in contact with the filling layer is independently provided from the filling layer, or a material of the lens element of the condenser lens structure in contact with the filling layer is the same as a material of the filling layer, and the lens element of the condenser lens structure in contact with the filling layer and the filling layer are integrally formed.

7. The light-emitting substrate according to claim 6, wherein A refractive index of the light-emitting element is greater than a refractive index of the filling layer, and the refractive index of the filling layer is greater than or equal to a refractive index of the lens element of the condenser lens structure in contact with the filling layer.

8. The light-emitting substrate according to claim 1, wherein The light-emitting substrate further includes a filling layer located between the lens structure layer and the substrate, and among each of the condenser lens structures, a lens element with the smallest distance from the filling layer is in contact with the filling layer; and / or, the second lens element covers a surface of the first lens element away from the substrate, and the first lens element is in contact with the second lens element.

9. The light-emitting substrate according to claim 1, wherein The light-emitting substrate further includes an isolation structure located between the substrate and the lens structure layer, the isolation structure is provided with at least one groove, and each of the light-emitting elements corresponding to one of the condenser lens structures is located in one of the grooves; a material of the isolation structure is a light-absorbing material or a metal.

10. A light-emitting device, characterized in that, The light-emitting device includes the light-emitting substrate according to any one of claims 1 to 9.

Images