Micro-led lighting device with combination of reflective cup and lens and preparation method thereof

Abstract

The application provides a Micro-LED lighting device with a combination of a reflecting cup and a lens and a preparation method thereof. The lighting device comprises a transparent substrate, a Fresnel lens array, a reflecting cup array and a Micro-LED chip. The reflecting cup is coaxially arranged with the Fresnel lens in one-to-one correspondence. The first opening diameter of the reflecting cup ranges from 5 to 15 microns, and the radius of the Fresnel lens ranges from 10 to 25 microns. The parabolic surface parameter of the reflecting cup satisfies that the ratio of the focal length f to the chip size ranges from 5 to 20. The combination of the reflecting cup and the Fresnel lens provides collimation and high efficiency for the chip. The reflecting cup converges the light emitted by the chip, thereby playing a role in preliminary collimation. The Fresnel lens performs secondary collimation on the converged light, thereby effectively improving the collimation effect and the luminous efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of Micro-LED display and the field of optical precision manufacturing, and particularly relates to a Micro-LED lighting device with a combination of a reflecting cup and a lens. BACKGROUND

[0002] With the rapid development of LED lighting technology, LED lamps are widely used in the lighting field due to their advantages of environmental protection, energy saving, high light efficiency and long service life. However, the light distribution of the current market LED directional lighting, spotlight and flashlight products is mainly based on a single reflecting cup or a condensing lens. This design has some limitations, especially when a single COB light source board is used. Since the light-emitting surface of the COB light source board is large, it is difficult to achieve small-angle uniform light distribution. In addition, the traditional reflecting cup or lens design also has some problems in optical performance, such as stray light intensity, non-uniform light spot, poor condensing effect, large light color difference, etc., resulting in low light efficiency of the light source.

[0003] Under this background, the emergence of Micro-LED technology provides a new idea to solve the above problems. Micro-LED is a new type of solid-state light source, which has the advantages of self-luminous, fast response speed, low energy consumption and long service life. However, how to effectively converge and collimate the light of Micro-LED to improve its light efficiency is still a technical problem to be solved. SUMMARY

[0004] The purpose of the present application is to provide a Micro-LED lighting device with a combination of a reflecting cup and a lens and a preparation method thereof. The light beam emitted by the Micro-LED is first converged by the reflecting cup with a reflecting layer, then collimated by the Fresnel lens for the second time, and finally collimated out by the transparent glass substrate. The effective convergence and collimation of the light of the Micro-LED can be realized, thereby improving the overall light efficiency.

[0005] To achieve the above purpose, the present application provides a Micro-LED lighting device with a combination of a reflecting cup and a lens, comprising:

[0006] a transparent substrate;

[0007] a Fresnel lens array arranged on the transparent substrate, comprising a plurality of Fresnel lenses arranged in an array, the annular surface of the Fresnel lens is close to the transparent substrate, and the annular surface is filled with a first photoresist layer;

[0008] A Fresnel lens array is arranged on the transparent substrate, and comprises a plurality of Fresnel lenses arranged in an array, wherein the Fresnel lenses are arranged in one-to-one correspondence with the Micro-LEDs and the Fresnel lenses are arranged coaxially with the Micro-LEDs.

[0009] A Micro-LED chip is arranged on the array of the Fresnel lenses, and comprises a plurality of Micro-LEDs arranged in an array, wherein the Micro-LEDs are arranged in one-to-one correspondence with the array of the Fresnel lenses and the light-emitting surfaces of the Micro-LEDs are arranged at the first openings of the array of the Fresnel lenses.

[0010] The diameter of the first opening of the array of the Fresnel lenses ranges from 5 μm to 15 μm, and the radius of the array of the Fresnel lenses ranges from 10 μm to 25 μm.

[0011] The parabolic parameter of the array of the Fresnel lenses satisfies that the ratio of the focal length f to the size of the light-emitting surface of the Micro-LED ranges from 5 to 20.

[0012] Optionally, the ratio of the diameter of the first opening of the array of the Fresnel lenses to the size of the light-emitting surface of the Micro-LED ranges from 1.0 to 1.5:1.

[0013] Optionally, the light-emitting surface of the Micro-LED is circular or square, and the size of the light-emitting surface of the Micro-LED is the diameter of the circular light-emitting surface or the width of the square light-emitting surface.

[0014] Optionally, the surface type of the array of the Fresnel lenses satisfies the equation: z=(x²+y²) / 4f, wherein f is the focal length.

[0015] Optionally, the radius of the second opening of the array of the Fresnel lenses is less than or equal to the radius of the array of the Fresnel lenses.

[0016] Optionally, the width d of the annular zone of the array of the Fresnel lenses satisfies: d≤λ / (2NA), wherein λ is the central wavelength of the Micro-LED, and NA is the numerical aperture of the lens.

[0017] Optionally, the refractive index of the array of the Fresnel lenses ranges from 1.3 to 1.6; and / or

[0018] The ratio of the refractive index of the transparent substrate to the refractive index of the array of the Fresnel lenses ranges from 0.9 to 1.1:1.

[0019] The application further provides a preparation method of a Micro-LED lighting device with a combination of a light cup and a lens, and the preparation method comprises the following steps:

[0020] S1. A Fresnel lens array master is prepared by a photolithography technology.

[0021] S2. Transferring the Fresnel lens array to the transparent substrate by nanoimprint technology;

[0022] S3. Coating a first photoresist layer on the Fresnel lens array;

[0023] S4. Preparing a retroreflective cup array master by photolithography technology;

[0024] S5. Transferring the retroreflective cup array to the side of the Fresnel lens array away from the transparent substrate by nanoimprint technology;

[0025] S6. Preparing a reflective layer by evaporation or electroplating technology;

[0026] S7. Coating a second photoresist layer on the retroreflective cup array with the reflective layer;

[0027] S8. Removing part of the second photoresist layer to obtain a first opening of the retroreflective cup;

[0028] S9. Integrating the Fresnel lens array and the retroreflective cup array structure on the Micro-LED chip to obtain a Micro-LED illumination device with a combination of retroreflective cups and lenses.

[0029] Optionally, the preparation method of the retroreflective cup array master comprises:

[0030] forming a continuous parabolic surface on the photoresist using gray-scale lithography technology;

[0031] transferring the parabolic surface to a quartz substrate by nanoimprint technology.

[0032] Optionally, the preparation method of the Fresnel lens array master comprises:

[0033] adopting laser gray-scale direct writing lithography technology to prepare a ring belt structure;

[0034] forming a stepped cross section by gray-scale exposure and development.

[0035] According to the scheme of the present application, (1) the combination of the retroreflective cup and the Fresnel lens provides collimation and high efficiency for the Micro-LED, the retroreflective cup collects the light emitted by the Micro-LED and plays a role in preliminary collimation, and the Fresnel lens performs secondary collimation on the collected light, solving the problems of poor collimation effect and low luminous efficiency caused by single-layer lens array and other means;

[0036] (2) the master is prepared by using photolithography technology, which ensures that the retroreflective cup has good high-order aspheric surface under micro-nano scale, solving the problems of low component precision, no allowable error and high manufacturing cost under micro-nano scale;

[0037] (3) The double-layer aspheric microlens array structure is simple in structure, simple in preparation method, and effective in improving the light collimation degree of the Micro-LED.

[0038] The above description is only a summary of the technical scheme of the present application. In order to more clearly understand the technical means of the present application and to implement the content of the description, the following will be described in detail with the preferred embodiments of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 A structure schematic diagram of a Micro-LED lighting device with a combination of a reflective cup and a lens is provided for an exemplary embodiment of the present application;

[0040] Figure 2 A schematic diagram of an embossed Fresnel lens array is provided for an exemplary embodiment of the present application;

[0041] Figure 3 A schematic diagram of coating a low-refractive glue on the Fresnel lens array is provided for an exemplary embodiment of the present application;

[0042] Figure 4 A structure schematic diagram of aligning and transferring a reflective cup array on the Fresnel lens array is provided for an exemplary embodiment of the present application;

[0043] Figure 5 A schematic diagram of coating a reflective layer on the reflective cup is provided for an exemplary embodiment of the present application;

[0044] Figure 6 A schematic diagram of a photoresist encapsulating the reflective cup structure is provided for an exemplary embodiment of the present application;

[0045] Figure 7 A schematic diagram of a reflective cup truncation opening method is provided for an exemplary embodiment of the present application;

[0046] Figure 8 A schematic diagram of the entire structure after alignment is provided for an exemplary embodiment of the present application.

[0047] Wherein, transparent substrate-1; Fresnel lens array-2; Fresnel lens-21; reflective cup array-3; reflective cup-31; first opening-32; second opening-33; Micro-LED chip-4; reflective layer-5; second photoresist layer-6; first photoresist layer-7. DETAILED DESCRIPTION

[0048] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work are within the protection scope of the present application.

[0049] In order for those skilled in the art to better understand the technical solutions of the present application, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0050] The Micro-LED chip has a high-density integrated LED array with a micron-level pitch, and each Micro-LED in the Micro-LED array can be independently addressed and lit as a light-emitting surface to emit a pixel light beam. The size of the light-emitting surface is generally 1-100 microns, and the pitch between adjacent light-emitting surfaces is extremely small, generally 1-200 microns, and the light beams emitted by the light-emitting surfaces generally have a certain divergence angle, so that there is a stray light effect in the Micro-LED array. When the Micro-LED chip is applied to directional lighting, spotlights, and flashlights, etc., without regulating the light emitted by the Micro-LED, it is difficult to meet the requirements of directional lighting.

[0051] When the light emitted by the Micro-LED chip needs to be collimated, most of the conventional methods use a microlens array to refract and collimate the light emitted by the light-emitting chip at the critical surface to achieve collimation. This method has certain risks, and the collimation effect is affected by lens processing precision and alignment error with the light-emitting chip. Moreover, for lens regulation, the light converging ability is insufficient, which easily causes the problem of low light efficiency. Light extraction efficiency and light utilization rate have always been a difficult problem to be solved for Micro-LED chips. Other phase regulation methods, such as super surface collimation, have the problems of high processing cost, etc., which have a greater impact on mass production.

[0052] Please refer to Figure 1 An exemplary embodiment of the present application provides a Micro-LED lighting device with a combination of a light-reflecting cup and a lens, which includes a transparent substrate 1, a Fresnel lens array 2 arranged on the transparent substrate 1, a light-reflecting cup array 3 arranged on the Fresnel lens array 2, and a Micro-LED chip 4 arranged on the light-reflecting cup array 3.

[0053] The Micro-LED chip 4 comprises a plurality of Micro-LEDs arranged in an array. The light emitting surface of the Micro-LED can be circular or square, and the size of the light emitting surface of the Micro-LED ranges from 1 to 100 microns. When the light emitting surface of the Micro-LED is circular, the size of the light emitting surface is the diameter of the circle; when the light emitting surface of the Micro-LED is square, the size of the light emitting surface is the width of the square. The shape of the light emitting surface is not specifically limited herein and can also be other shapes such as hexagonal, etc., which are not listed one by one herein.

[0054] Please refer to Figure 1 and Figure 7 The reflective cup array 3 is arranged between the Micro-LED chip 4 and the Fresnel lens array 2. The reflective cup array 3 comprises a plurality of reflective cups 31 arranged in an array, the first opening 32 is arranged at the end of the reflective cup 31 away from the Fresnel lens array 2, and the second opening 33 is arranged at the end of the reflective cup 31 close to the Fresnel lens array 2. The Micro-LED and the reflective cup 31 are arranged one by one, and the light emitting surface of the Micro-LED is arranged at the first opening 32, that is, the light emitting surface of each Micro-LED corresponds to the arrangement of a reflective cup 31. The light emitted by each Micro-LED light emitting surface enters the reflective cup 31 through the first opening 32 for beam collection, and is emitted from the second opening 33. The diameter of the first opening 32 of the reflective cup 31 needs to be greater than or equal to the size of the light emitting surface of the Micro-LED, so that the Micro-LED can enter the reflective cup 31 completely. In order to reduce the loss of light, the first opening 32 covers the light emitting surface of the Micro-LED. The ratio of the diameter of the first opening 32 of the reflective cup 31 to the size of the light emitting surface of the Micro-LED is 1.0-1.5:1, so as to achieve the maximum beam collection capability. The first opening 32 of the reflective cup 31 cannot be too large, because the Micro-LED is an array structure, and the light emitting surface is arranged periodically. If the first opening 32 is too large, the reflective cup 31 corresponding to the adjacent light emitting surface will have crosstalk, which will reduce the beam collection capability.

[0055] The inner surface of the reflective cup 31 is provided with a reflective layer 5 for reflecting the light irradiated on the inner wall of the reflective cup 31. In the embodiment, the first opening 32 and the second opening 33 are both circular, and the diameter of the first opening 32 is smaller than the diameter of the second opening 33, so as to ensure that the light is directly irradiated on the inner wall of the reflective cup 31, and is emitted from the larger second opening 33 after multiple reflections, forming a directional light beam, reducing light loss, and making the light beam more concentrated. The reflective layer 5 can be an aluminum layer or a chromium layer prepared from a material capable of reflecting the light emitted by the Micro-LED.

[0056] The first opening 32 has a diameter ranging from 5 μm to 15 μm, and the second opening 33 has a diameter ranging from 10 μm to 25 μm.

[0057] The parabolic parameter of the reflective cup 31 satisfies that the ratio of the focal length f to the size of the Micro-LED light-emitting surface ranges from 5 to 20. The reflective cup can converge the light emitted by the Micro-LED to a certain extent, but cannot completely collimate the light. The remaining collimation is performed by the Fresnel lens in the case of convergence of the divergence angle. When the ratio of the focal length f to the size of the Micro-LED light-emitting surface is less than 5, the light emitted by the Micro-LED is collimated by the reflective cup, and the collimation is too large, which has a negative effect. The light originally reflected to the upper wall is reflected to the lower wall. When the ratio of the focal length f to the size of the Micro-LED light-emitting surface is greater than 20, the reflective cup cannot converge the light emitted by the Micro-LED, and the effect after collimation by the Fresnel lens is poor.

[0058] The surface type of the reflective cup 31 satisfies the equation: z=(x²+y²) / 4f, where f is the focal length. The position of the Micro-LED can be flexibly set. The Micro-LED is preliminarily collimated by the reflective cup 31, and is collimated again by the Fresnel lens 21. When the Micro-LED is placed at the focal point of the parabolic reflective cup, the divergent light of the Micro-LED can be efficiently reflected into a quasi-parallel light beam, which significantly improves the directivity and light energy utilization of the light source.

[0059] Please refer to Figure 1 , Figure 6 and Figure 7 . It should be noted that the outer periphery of the reflective cup 31 is filled with the second photoresist layer 6. The second photoresist layer 6 can be made of any photoresist with a refractive index, which has no effect on the collimation of light.

[0060] Please refer to Figures 1 to 3 . The Fresnel lens array 2 includes a plurality of Fresnel lenses 21 arranged in an array. The reflective cup 31 is coaxially arranged with the Fresnel lens 21 one-to-one. The number of the reflective cup 31, the Fresnel lens 21 and the Micro-LED light-emitting surface is the same. Each Micro-LED light-emitting surface is provided with one reflective cup 31 and one Fresnel lens 21. The light emitted by the Micro-LED light-emitting surface is reflected and converged by the reflective cup 31, which plays a role in preliminary collimation. The preliminarily collimated light enters the Fresnel lens 21 for secondary convergence and collimation.

[0061] The ring width d of the Fresnel lens 21 satisfies: d≤λ / (2NA), where λ is the central wavelength of the Micro-LED, and NA is the numerical aperture of the lens.

[0062] The refractive index of the Fresnel lens 21 is 1.3-1.6. The radius of the Fresnel lens 21 ranges from 10 μm to 25 μm. The first photoresist layer 7 is filled in the annular zone of the Fresnel lens 21. The refractive index of the first photoresist layer 7 is lower than that of the Fresnel lens 21, and the refractive index of the first photoresist layer 7 ranges from 1.3 to 1.6. By changing the refractive index of the reflecting cup 31 and the Fresnel lens 21, the refracted light at the interface is refracted, and the collimation effect is improved.

[0063] The reflecting cup 31 and the corresponding Fresnel lens 21 are coaxially aligned, and the radius of the second opening 33 of the reflecting cup 31 is less than or equal to the radius of the Fresnel lens 21, so that the light collected by the reflecting cup 31 can all enter the Fresnel lens 21 for collimation.

[0064] The Fresnel lens array 2 is arranged on the transparent substrate 1, and the annular zone of the Fresnel lens 21 is close to the transparent substrate 1. The transparent substrate 1 is a transparent flat plate made of a transparent material such as a glass substrate. The refractive index of the transparent substrate 1 is equal to or close to the refractive index of the Fresnel lens 21, so that the direction of the light emitted by the Micro-LED does not change after collimation by the light-emitting cup and the Fresnel lens 21 and then passing through the transparent substrate 1. Alternatively, the ratio of the refractive index of the transparent substrate 1 to the refractive index of the Fresnel lens 21 is 0.9-1.1:1. When a glass substrate is selected as the transparent substrate 1, the refractive index of the transparent substrate 1 is 1.52.

[0065] The combination of the reflecting cup 31 and the Fresnel lens 21 provides collimation and high efficiency for the Micro-LED. The reflecting cup 31 collects the light emitted by the Micro-LED and performs preliminary collimation, and the Fresnel lens 21 performs secondary collimation on the collected light, solving the problems of poor collimation effect and low luminous efficiency caused by single-lens array and other means.

[0066] The application also provides a preparation method of a Micro-LED lighting device with a combination of a reflecting cup and a lens, which comprises the following steps:

[0067] S1. Preparing a Fresnel lens array master by a photolithography technology;

[0068] S2. Transferring the Fresnel lens array to a transparent substrate by a nano-imprinting technology;

[0069] S3. Coating a first photoresist layer on the Fresnel lens array;

[0070] S4. Preparing a reflecting cup array master by a photolithography technology;

[0071] S5. Transferring the reflecting cup array to the side of the Fresnel lens array away from the transparent substrate by a nano-imprinting technology;

[0072] S6. Preparing a reflective layer by evaporation or electroplating technology;

[0073] S7. Coating a second photoresist layer on the array of light-reflecting cups with the reflective layer;

[0074] S8. Removing part of the second photoresist layer to obtain a first opening of the light-reflecting cup;

[0075] S9. Integrating the array of Fresnel lens and the array of light-reflecting cup structure on the Micro-LED chip to obtain a Micro-LED lighting device with light-reflecting cup and lens combination.

[0076] It should be noted that the above step sequence is not limited, and the above is only an example. Alternatively, steps S1 and S2 can be completed, and then other steps are performed.

[0077] The preparation of the Fresnel lens array master can use laser direct writing lithography technology, laser gray scale direct writing lithography technology, electron beam lithography technology, mask lithography technology, etc. The preparation of the light-reflecting cup array master can also use laser direct writing lithography technology, laser gray scale direct writing lithography technology, electron beam lithography technology, mask lithography technology, etc.

[0078] In this embodiment, please refer to Figure 2 When the Fresnel lens array is transferred to the transparent substrate by nanoimprint technology, the refractive index of the UV glue used is equal to or close to the refractive index of the transparent substrate, and the refractive index of the selected UV glue is in the range of 1.3-1.6. After the transfer is completed, the Fresnel lens array and the master are separated, and a uniform Fresnel lens array is formed on the transparent substrate. Please refer to Figure 3 A layer of photoresist is coated on the Fresnel lens array and cured to form a uniform first photoresist layer. Please refer to Figure 4 and Figure 5 Then, a light-reflecting cup array with a parabolic surface is transferred to the Fresnel lens array by nanoimprint technology, and after completion, it is cured and demolded, and a reflective layer is plated by evaporation or electroplating. Please refer to Figure 6 A layer of photoresist is coated or imprinted on the reflective layer for packaging, and the photoresist forms a second photoresist layer. Alternatively, after the preparation of the reflective layer is completed, the photoresist is exposed and cured to form a second photoresist layer with a flat surface. Please refer to Figure 7 The second photoresist layer is removed by laser or imprint demolding means to control the opening diameter of the light-reflecting cup at the cutting position to be 1-1.5 times the size of the Micro-LED light-emitting surface. Please refer to Figure 1 The light-reflecting cup and Fresnel lens combination structure are integrated on the Micro-LED chip by inverted gluing to complete the preparation of the high-efficiency high-collimation Micro-LED lighting device with light-reflecting cup and lens combination.

[0079] It should be noted that, in order to ensure the coaxial alignment of the reflector cup and the Fresnel lens, the preparation method further comprises: referring to Figure 8 A target is arranged on the Fresnel lens array, and the imprinting position of the reflector cup array is confirmed based on the target. This method is simple to operate, and the coaxial alignment accuracy is high, ensuring the collimation effect of the light emitted by the subsequent Micro-LED. Specifically, the first target is arranged on the Fresnel lens array master, and the first target is a concave structure or a convex structure. The target is arranged on the Fresnel lens array by nano-imprinting technology. The second target is arranged on the reflector cup array master, and the second target is a convex structure or a concave structure; when the second target is aligned with the target on the Fresnel lens array, the Fresnel lens is aligned with the parabolic convex structure on the reflector cup master.

[0080] In an embodiment, the preparation method of the Fresnel lens array master comprises:

[0081] The annular structure is prepared by using laser gray-scale direct writing lithography technology.

[0082] The step-shaped cross section is formed by gray-scale exposure and development.

[0083] The Fresnel lens array master prepared by laser gray-scale direct writing lithography technology is provided with the structure of the Fresnel lens, including the lens surface and the annular structure of the waveband. The Fresnel lens array master is made of photoresist material. The Fresnel lens array template is obtained by transferring the Fresnel lens array master by nano-imprinting technology, so that the surface of the Fresnel lens array template to be imprinted forms a matching Fresnel annular groove array. The Fresnel lens array master is obtained by transferring the Fresnel lens template by nano-imprinting technology, so that the Fresnel lens array master forms a Fresnel annular convex array matched with the Fresnel lens.

[0084] The preparation method of the reflector cup array master comprises:

[0085] A continuous parabolic surface is formed on the photoresist by using gray-scale lithography technology.

[0086] The parabolic surface is transferred to the quartz substrate by nano-imprinting technology.

[0087] The reflector cup array master is obtained by gray-scale lithography technology, and the reflector cup array master is provided with a convex array of reflector cup parabolic surfaces. The reflector cup array master is made of photoresist material. The reflector cup array template is obtained by transferring the reflector cup array master by nano-imprinting technology, so that the surface of the reflector cup template to be imprinted forms a reflector cup concave array matched with the reflector cup convex array.

[0088] The master is prepared by using a photoetching technology, good high-order aspheric surface of the micro-nano scale reflecting cup is ensured, and problems of low precision, no allowable error and high manufacturing cost of the element under the micro-nano scale are solved; the double-layer aspheric microlens array structure is simple in structure, simple in preparation method, and effective in improving the light collimation of the Micro-LED.

[0089] The technical features of the above embodiments can be combined in any manner, and to make the description concise, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the description.

[0090] The above embodiments only express several implementation manners of the present application, the description is more specific and detailed, but it should not be understood as the limitation of the patent scope of the present application. It should be pointed out that, for ordinary skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A Micro-LED lighting device comprising a reflector cup and a lens combination, characterized in that, include: Transparent substrate; A Fresnel lens array is disposed on the transparent substrate, comprising a plurality of Fresnel lenses arranged in an array, wherein the annular surface of the Fresnel lenses is close to the transparent substrate, and the annular surface of the Fresnel lenses is filled with a first photoresist layer; A reflector array, disposed on the Fresnel lens array, includes a plurality of reflectors arranged in an array, each reflector corresponding to a Fresnel lens and coaxially disposed, each reflector having a first opening at the end away from the Fresnel lens array and a second opening at the end closer to the Fresnel lens array, and a reflective layer provided on the inner surface of the reflector. Micro-LED chips are disposed on the reflector array, including a plurality of Micro-LEDs arranged in an array, wherein each Micro-LED and the reflector are disposed in a one-to-one correspondence and the light-emitting surface of the Micro-LED is disposed at the first opening; The diameter of the first opening of the reflector cup ranges from 5μm to 15μm, and the radius of the Fresnel lens ranges from 10μm to 25μm. The parabolic parameters of the reflector cup satisfy the following: the ratio of focal length f to the size of the Micro-LED light-emitting surface is in the range of 5-20.

2. The Micro-LED lighting device with a reflector and lens combination according to claim 1, characterized in that, The ratio of the diameter of the first opening of the reflector cup to the size of the Micro-LED light-emitting surface is 1.0-1.5:

1.

3. The Micro-LED lighting device with a reflector and lens combination according to claim 1 or 2, characterized in that, The Micro-LED light-emitting surface is circular or square, and the size of the Micro-LED light-emitting surface is the diameter of the circle or the width of the square.

4. The Micro-LED lighting device with a reflector and lens combination according to claim 1, characterized in that, The surface shape of the reflector satisfies the equation: z=(x²+y²) / 4f, where f is the focal length.

5. The Micro-LED lighting device with a reflector and lens combination according to claim 1, characterized in that, The radius of the second opening of the reflector cup is less than or equal to the radius of the Fresnel lens.

6. The Micro-LED lighting device with a reflector and lens combination according to claim 1, characterized in that, The band width d of the Fresnel lens satisfies: d≤λ / (2NA), where λ is the center wavelength of the Micro-LED and NA is the numerical aperture of the lens.

7. The Micro-LED lighting device with a reflector and lens combination according to claim 1, characterized in that, The Fresnel lens has a refractive index of 1.3-1.6; and / or The ratio of the refractive index of the transparent substrate to the refractive index of the Fresnel lens is 0.9-1.1:

1.

8. A method for manufacturing a Micro-LED lighting device comprising a reflector cup and a lens combination, characterized in that, The preparation method includes: S1. Fabrication of a Fresnel lens array master using photolithography; S2. A Fresnel lens array is transferred to a transparent substrate using nanoimprint technology; S3. Coat the first photoresist layer onto the Fresnel lens array; S4. Fabricate a master template for the reflective cup array using photolithography; S5. The reflective cup array is transferred to the side of the Fresnel lens array away from the transparent substrate using nanoimprint technology; S6. Prepare the reflective layer using vapor deposition or electroplating techniques; S7. Coat a second photoresist layer onto the reflective cup array with a reflective layer; S8. Remove part of the second photoresist layer to obtain the first opening of the reflector cup; S9. Integrate the Fresnel lens array and reflector array structure onto the Micro-LED chip to obtain a Micro-LED lighting device with a reflector and lens combination.

9. The method for manufacturing a Micro-LED lighting device with a reflector cup and lens combination according to claim 8, characterized in that, The method for preparing the reflector array master includes: A continuous parabolic surface is formed on photoresist using grayscale lithography. Parabolic shapes are transferred to quartz substrates using nanoimprint technology.

10. The method for manufacturing a Micro-LED lighting device with a reflector cup and lens combination according to claim 8, characterized in that, The method for preparing the Fresnel lens array master includes: The ring structure was fabricated using laser grayscale direct-write lithography. A stepped profile is formed by grayscale exposure and development.

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