Mini-LED Display Module and Its Preparation Method and Application

Abstract

This application belongs to the field of LED technology, and more particularly relates to a Mini-LED display module, its preparation method, and application. The provided Mini-LED display module includes: a substrate; a plurality of LED chips; a first sealing layer; and a second sealing layer. The first sealing layer is arc-shaped. The first and second sealing layers contain different adhesive additives, including one or more of diffusion powder, colorant, quantum dot material, and resin additives. This improves the luminous efficiency of the Mini-LED display module and the contrast of the LED display.

Description

Technical Field

[0001] The present application belongs to the field of LED technology, and in particular relates to a Mini-LED display module and its preparation method and application. Background Art

[0002] Light-emitting diodes (LEDs) are a key component of many consumer products, such as general lighting, smartphones, displays, and automobiles. They typically offer higher efficiency and durability, more compact size, and greater design flexibility. LEDs are currently the most widely used lighting source, with electro-optical conversion efficiencies exceeding 50%. As solid-state active light sources, LEDs offer high brightness, long life, fast response times, and are environmentally friendly.

[0003] The combination of semiconductor micro-nano manufacturing technology and LED technology has brought new possibilities. LEDs, reduced to micrometers, are called miniature light-emitting diodes (Mini-LEDs). Mini-LEDs offer numerous advantages and potential applications. They can be used in displays. Compared to current mainstream display technologies like OLED and LCD, Mini-LEDs offer higher brightness, resolution, and color saturation, lower energy consumption, longer lifespan, and faster response times.

[0004] Mini-LED contrast and color consistency are key factors affecting the display quality of display modules. Traditional packaging processes, due to the use of molding processes, are prone to batch variations in polymer material composition and the machining precision of production jigs. This can lead to mosaic effects and white mura in Mini-LEDs, as well as the common problem of low contrast. Summary of the Invention

[0005] The purpose of this application is to provide a Mini-LED display module and its preparation method and application, aiming to solve the mosaic effect and white mura problems of Mini-LED in the existing technology, as well as the common problem of low contrast that affects usage.

[0006] To achieve the above application objectives, the technical solutions adopted in this application are as follows:

[0007] In a first aspect, the present application provides a Mini-LED display module, comprising:

[0008] substrate;

[0009] A plurality of LED chips, wherein the LED chips are arranged on the first surface of the substrate;

[0010] A bonding layer, which is used for black masking and is provided in the gap between the first surface of the substrate where the LED chip is not provided;

[0011] The first sealing layer is arc-shaped and completely covers the LED chip and the adhesive layer, and the first sealing layer is used to change the light-emitting angle of the LED chip and improve the contrast;

[0012] A second sealing layer is provided on a side of the first sealing layer away from the LED chip and the adhesive layer and completely covers the first sealing layer; and the second sealing layer is used for protection;

[0013] The contact surface between the first sealing layer and the second sealing layer is a curved surface. The first sealing layer and the second sealing layer contain different glue additives, and the glue additives include one or more of diffusion powder, colorant, quantum dot material, and resin additives.

[0014] In a second aspect, the present application provides a method for preparing a Mini-LED display module, comprising the following steps:

[0015] Providing a substrate, and fixing a plurality of LED chips on a first surface of the substrate;

[0016] Prepare a glue layer on the first surface of the substrate where no LED chip is provided,

[0017] Prepare a first sealing layer on the side of the LED chip and the adhesive layer facing away from the substrate;

[0018] A second sealing layer is prepared on the side of the first sealing layer away from the LED chip and the adhesive layer to obtain a Mini-LED display module.

[0019] In a third aspect, the present application provides an electronic device, which includes a Mini-LED display module or a Mini-LED display module prepared by the method.

[0020] The first aspect of the present application provides a Mini-LED display module, which includes a first sealing layer and a second sealing layer, wherein the first sealing layer is arc-shaped, that is, the contact surface between the first sealing layer and the second sealing layer is a curved surface, which further improves the contrast of the Mini-LED display module; and the first sealing layer and the second sealing layer contain different glue additives, and the glue additives include one or more of diffusion powder, colorant, quantum dot material, and resin additives; because the first sealing layer and the second sealing layer contain different glue additives, on the one hand, the material properties of the two sealing layers obtained are different, so that the light is refracted, the luminous efficiency of the Mini-LED display module is improved, the light output angle of the LED chip is increased, and the uniformity of the mixed light is improved; on the other hand, it can solve the problem of cross-light between LEDs, effectively improve the contrast of the LED display and increase the transmittance of the LED light, and solve the mosaic effect and white mura problems that occur in the Mini-LED display module.

[0021] The second aspect of the present application provides a method for preparing a Mini-LED display module, which arranges an LED chip on the surface of a substrate, and then arranges a glue layer, a first sealing layer, and a second sealing layer in sequence; the preparation process is simple and does not require large-scale instruments and equipment. The prepared Mini-LED display module includes two sealing layers with different properties obtained by doping different glue additives, which solves the mosaic effect and white mura problems that occur in the Mini-LED display module, increases the luminous angle of the display screen and improves the contrast of the LED display, which is conducive to wide application.

[0022] The electronic device provided in the third aspect of the present application includes a Mini-LED display module or a Mini-LED display module prepared by the method. Since the provided Mini-LED display module does not have a mosaic effect or white mura problem, the electronic device using the Mini-LED display module can significantly improve the display contrast and clarity, and is suitable for a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0024] Figure 1 This is a schematic diagram of the Mini-LED display module provided in an embodiment of the present application.

[0025] Among them, the reference numerals in the figures are:

[0026] 1—substrate; 2—LED chip; 3—bonding layer; 4—first sealing layer; 5—second sealing layer. DETAILED DESCRIPTION

[0027] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0028] In this application, the term "and / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0029] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0030] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. Some or all of the steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0031] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0032] The weights of the relevant components mentioned in the examples of this application may not only refer to the specific content of each component, but also represent the weight ratio between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the examples of this application, it is within the scope disclosed in the examples of this application. Specifically, the mass in the examples of this application may be μg, mg, g, kg, etc., which are mass units known in the chemical industry.

[0033] The terms "first" and "second" are used solely for descriptive purposes to distinguish objects, such as substances, from one another and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features being referred to. For example, a first XX could also be referred to as a second XX, and similarly, a second XX could also be referred to as a first XX, without departing from the scope of the embodiments of this application. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more of such features.

[0034] In a first aspect, an embodiment of the present application provides a Mini-LED display module, such as Figure 1 As shown, the Mini-LED display module includes:

[0035] substrate1;

[0036] A plurality of LED chips 2, wherein the LED chips 2 are arranged on the first surface of the substrate 1;

[0037] The adhesive layer 3 is used for blackening and shielding, and is provided in the gap between the first surface of the substrate 1 where the LED chip 2 is not provided;

[0038] The first sealing layer 4 is arc-shaped and completely covers the LED chip 2 and the adhesive layer 3. The first sealing layer 4 is used to change the light-emitting angle of the LED chip and improve the contrast;

[0039] The second sealing layer 5 is arranged on the side of the first sealing layer 4 away from the LED chip 2 and the adhesive layer 3 and completely covers the first sealing layer 4; and the second sealing layer 5 is used for protection.

[0040] Among them, the contact surface between the first sealing layer 4 and the second sealing layer 5 is a curved surface, and the first sealing layer 4 and the second sealing layer 5 contain different glue additives, and the glue additives include one or more of diffusion powder, colorant, quantum dot material, and resin additives.

[0041] A first aspect of an embodiment of the present application provides a Mini-LED display module, which includes a first sealing layer 4 and a second sealing layer 5, wherein the first sealing layer 4 is arc-shaped and completely covers the LED chip 2 and the adhesive layer 3, that is, the contact surface of the first sealing layer and the second sealing layer is a curved surface. Setting the contact surface of the two sealing layers as a curved surface further improves the contrast of the Mini-LED display module; and the first sealing layer 4 and the second sealing layer 5 contain different glue additives, and the glue additives include one or more of diffusion powder, colorant, quantum dot material, and resin additives; because the first sealing layer 4 and the second sealing layer 5 contain different glue additives, on the one hand, the material properties of the two sealing layers are different, so that the light is refracted, the luminous efficiency of the Mini-LED display module is improved, the light output angle of the LED chip 2 is increased, and the uniformity of the mixed light is improved; on the other hand, it can reduce the problem of cross-light between LEDs, effectively improve the contrast of the LED display and increase the transmittance of the LED light, and solve the mosaic effect and white mura problems that occur in the Mini-LED display module.

[0042] In some embodiments, the Mini-LED display module includes a substrate 1, which can be selected from a conventional LED substrate. In some specific embodiments, the substrate 1 includes but is not limited to at least one of a flat substrate, a multilayer circuit board substrate, and a multilayer circuit board substrate with a driver IC.

[0043] In some embodiments, the Mini-LED display module includes several LED chips 2, which are arranged on the first surface of the substrate 1; wherein the LED chips 2 are arranged at intervals, the height of the LED chips 2 is 80 to 100 μm, and the LED chips 2 are spaced 20 to 30 μm apart.

[0044] In some embodiments, the LED chip 2 includes, but is not limited to, at least one of a tin electrode chip and a gold electrode chip, and the structure of the LED chip 2 includes, but is not limited to, at least one of a vertical chip, a face-up chip, or a flip-chip. The type and structure of the LED chip 2 can be selected based on the requirements of the specific embodiment.

[0045] In some embodiments, the Mini-LED display module includes a glue layer 3, which is used for blackening and shielding, and is arranged in the gap of the first surface of the substrate where the LED chip is not arranged; the provided glue layer 3 is used for blackening and shielding, which can absorb impurity light entering the Mini-LED display module, thereby eliminating the reflected light caused by the impurity light, and further improve the bonding effect with the first sealing layer 4, thereby improving the stability of the display module.

[0046] In some embodiments, the material of the binding layer is selected from materials that absorb light. In some embodiments, the material of the binding layer 3 includes at least one of polypropylene resin, black epoxy resin, black silicone resin, and black acrylic resin.

[0047] In some embodiments, the thickness of the adhesive layer 3 is 20 to 70 μm. The thickness of the adhesive layer 3 is set to be lower than the height of the LED chip 2 to ensure that the adhesive layer 3 can cover the surface of the substrate 1 where the LED chip 2 is not provided, thereby achieving a better absorption effect on impurity light. If the thickness is too low, it will affect the absorption of impurity light. If the thickness is too high, it will affect the luminescence effect of the LED chip 2. In some specific embodiments, the thickness of the adhesive layer 3 is 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, or 70 μm.

[0048] In some embodiments, the Mini-LED display module includes: a first sealing layer 4, which is arc-shaped and completely covers the LED chip 2 and the adhesive layer 3, and the first sealing layer 4 is used to change the light-emitting angle of the LED chip 2 and improve the contrast.

[0049] In some embodiments, the Mini-LED display module includes: a second sealing layer 5, which is arranged on the side of the first sealing layer 4 away from the LED chip 2 and the adhesive layer 3 and completely covers the first sealing layer 4; and the second sealing layer is used for protection.

[0050] In some embodiments, the contact surface between the first sealing layer 4 and the second sealing layer 5 is a curved surface, which is beneficial for the first sealing layer 4 to be used to change the light-emitting angle of the LED chip 2 and improve the contrast.

[0051] In some embodiments, the first sealing layer 4 is arc-shaped, further improving the contrast of the Mini-LED display module. In some specific embodiments, the first sealing layer 4 is selected from at least one of an arc and a semicircle.

[0052] In some embodiments, the angle α between the first sealant layer 4 and the adhesive layer 3 is 30° < α < 90°. By controlling the angle between the first sealant layer 4 and the adhesive layer 3, the circular amplitude of the arc of the first sealant layer 4 is controlled. The larger the angle between the first sealant layer 4 and the adhesive layer 3, the larger the circular amplitude of the arc of the first sealant layer 4, and the higher the contrast of the Mini-LED display module.

[0053] Furthermore, the first and second sealing layers 4 and 5 contain different adhesive additives. Because the first and second sealing layers 4 and 5 contain different adhesive additives, on the one hand, the different material properties of the two sealing layers result in refraction of light, thereby improving the luminous efficiency of the Mini-LED display module, increasing the light output angle of the LED chip 2, and enhancing light mixing uniformity. On the other hand, this can solve the problem of light crosstalk between LEDs, effectively improving the contrast of the LED display and increasing the transmittance of the LED light, thereby resolving the mosaic effect and white mura problems that occur in Mini-LED display modules.

[0054] In some embodiments, the first sealing layer 4 or the second sealing layer 5 comprises, based on a total mass of 100%, 90-99.5% resin and 0.5-10% glue additive. The resin is used as the base material for the first sealing layer 4 or the second sealing layer 5 to ensure that the obtained first sealing layer 4 or the second sealing layer 5 has a certain degree of adhesion, can be tightly combined with other components, and ensures a high stability of the glue layer. The resin is further mixed with the glue additive to synergistically change the raw material properties of the mixed first sealing layer 4 or the second sealing layer 5. Since the glue additive included in the first sealing layer 4 is different from the glue additive included in the second sealing layer 5, the two sealing layers obtained based on the different glue additives have different refractive indices, different light absorption degrees, or different display contrasts, thereby improving the mosaic effect and white mura problems that occur in the Mini-LED display module.

[0055] In some embodiments, in the first sealing layer 4 or the second sealing layer 5 , the mass percentage of the resin is 90-99.5%, based on the total mass of the first sealing layer 4 or the second sealing layer 5 being 100%.

[0056] In some embodiments, the resin includes at least one of an epoxy resin, an epoxy-modified resin, a silicone resin, and a silicone-modified resin. The provided resins all have high performance, and the other raw material components can be evenly distributed in the matrix resin, forming a functional adhesive layer with uniform film thickness and stable performance. This improves the bonding stability between the adhesive layers, thereby enhancing the encapsulation effect of the encapsulation film on the LED display module.

[0057] Furthermore, in the provided first sealing layer 4 or second sealing layer 5, the mass percentage of the glue additive material is 0.5-10%, based on the total mass of the first sealing layer 4 or the second sealing layer 5 being 100%; if the amount of glue additive material added is too small, the properties of the obtained first sealing layer 4 and the second sealing layer 5 are not much different, which is not conducive to the refraction of light, thereby improving the luminous efficiency of the Mini-LED display module, and is not conducive to effectively improving the contrast of the LED display and increasing the transmittance of the LED light; if the amount of glue additive material added is too much, it will affect the overall characteristics of the obtained Mini-LED display module, which is not conducive to the use of the Mini-LED display module.

[0058] In some specific embodiments, based on the total mass of the first sealing layer 4 or the second sealing layer 5 as 100%, the mass percentage of the glue additive is selected from 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, and 10%.

[0059] Furthermore, the glue additive includes one or more of diffusion powder, colorant, quantum dot material, and resin additive. By adding the glue additive, on the one hand, the material properties of the two resulting sealing layers are different, causing light to refract, thereby improving the luminous efficiency of the Mini-LED display module, increasing the light output angle of the LED chip 2, and improving the uniformity of light mixing. On the other hand, it can also solve the problem of light crosstalk between LEDs, effectively improving the contrast of the LED display and increasing the transmittance of the LED light, and solving the mosaic effect and white mura problems that occur in Mini-LED display modules.

[0060] In some embodiments, the glue additive material is selected from diffusion powder. Adding diffusion powder can increase the scattering and transmission of light, making the light transmission effect better, thereby increasing the light-emitting angle of the display screen.

[0061] In some specific embodiments, the diffusion powder includes at least one of fumed silica, magnesium oxide, barium sulfate, and calcium carbonate.

[0062] In some embodiments, the glue additive material is selected from colorants. The addition of colorants can improve the absorption of photons and have a higher absorption effect on impurity light irradiated to the LED display module, reducing the reflection of incident light; at the same time, it can solve the problem of light crosstalk between LEDs, improve the contrast of LED display, and effectively increase the transmittance of LED light.

[0063] In some specific embodiments, the colorant includes at least one of carbon black, graphene, carbon powder, carbon nanotubes, and black color paste.

[0064] In some embodiments, the glue additive material is selected from quantum dot materials. By adding quantum dot materials, the sealing layer can realize the luminous light pattern of the quantum dot materials, making the obtained LED display module more convenient to use.

[0065] In some embodiments, the quantum dot material includes at least one of a perovskite quantum dot material and a cadmium quantum dot material.

[0066] In some embodiments, the glue additive is selected from a resin additive, wherein the resin additive includes at least one resin additive having a refractive index of 1.1 to 1.8. By adding resin additives with different refractive indices, the resulting sealant layer has different refractive indices, which refracts light and increases the luminous angle of the display.

[0067] In some specific embodiments, the refractive index of the second encapsulation layer 5 is smaller than that of the first encapsulation layer to create a light refraction effect, thereby increasing the light emitting angle of the display screen.

[0068] In some embodiments, in the Mini-LED display module, the first sealing layer 4 includes a resin additive with a refractive index of 1.4 to 1.8 and a mass percentage of 1% to 10%, and the second sealing layer 5 includes a resin additive with a refractive index of 1.1 to 1.3 and a mass percentage of 1% to 10%; by setting sealing layers with different refractive indices, the luminous efficiency of the backlight module is significantly improved, the light output angle of the LED chip 2 is increased, and the uniformity of the mixed light is improved.

[0069] In some embodiments, in the Mini-LED display module, the first sealing layer 4 includes a diffusion powder with a mass percentage of 1% to 10%, and the second sealing layer 5 includes a colorant with a mass percentage of 0.5% to 5%; the diffusion powder is added to the first sealing layer 4 to improve the light transmission effect; and the second sealing layer 5 containing the colorant can cooperate with the colorant to improve the absorption degree of photons, and has a high absorption effect on impurity light irradiated to the LED display module, reducing the reflection of incident light; at the same time, it can solve the problem of cross-light between LEDs, improve the contrast of LED display, effectively increase the transmittance of LED light, and can solve the white mura problem caused by the second sealing layer 5.

[0070] In some embodiments, in a Mini-LED display module, the first sealing layer 4 includes a quantum dot material with a mass percentage of 1% to 10%, and the second sealing layer 5 includes a diffusion powder with a mass percentage of 1% to 10%; on the one hand, this combined structure can prevent direct contact between the quantum dot material and the environment, thereby improving the service life of the quantum dot material, and by setting the quantum dot material in the first sealing layer 4, the luminous light type of the quantum dot material can be ensured; on the other hand, it can diverge the light type, increase the luminous angle, and improve the application of the Mini-LED display module.

[0071] In some embodiments, the thickness of the first sealing layer 4 is 100-120 μm. Setting the thickness of the first sealing layer 4 to a moderate level helps ensure that the LED chip 2 and the adhesive layer 3 are completely covered. In some specific embodiments, the thickness of the first sealing layer 4 is 100 μm, 105 μm, 110 μm, 115 μm, or 120 μm.

[0072] In some embodiments, the thickness of the second sealing layer 5 is 150 to 300 μm. Setting the thickness of the second sealing layer 5 to a moderate level helps ensure complete coverage of the first sealing layer 4, thereby better coordinating with the glue additive to address the white mura issue caused by the second sealing layer 5. In some specific embodiments, the thickness of the second sealing layer 5 is 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, or 200 μm.

[0073] A second aspect of the present application provides a method for preparing a Mini-LED display module, comprising the following steps:

[0074] S01 provides a substrate 1, a plurality of LED chips 2 are fixed to the first surface of the substrate 1;

[0075] S02. A first surface of the substrate 1 is not provided with an LED chip 2 and a glue layer 3 is prepared.

[0076] S03. A first sealing layer 4 is prepared on the side of the LED chip 2 and the adhesive layer 3 away from the substrate 2;

[0077] S04. Prepare a second sealing layer 5 on the side of the first sealing layer 4 away from the LED chip 2 and the adhesive layer 3 to obtain a Mini-LED display module.

[0078] The second aspect of the embodiment of the present application provides a method for preparing a Mini-LED display module. The method arranges an LED chip 2 on the surface of a substrate 1, and then arranges a glue layer 3, a first sealing layer 4, and a second sealing layer 5 in sequence; the preparation process is simple and does not require large-scale instruments and equipment. The prepared Mini-LED display module includes two sealing layers with different properties obtained by doping different glue additives, which solves the mosaic effect and white mura problems that occur in the Mini-LED display module, increases the luminous angle of the display screen and improves the contrast of the LED display, which is conducive to wide application.

[0079] In step S01 , a substrate 1 is provided, and a plurality of LED chips 2 are sequentially and spaced apart and fixed on a first surface of the substrate 1 , which helps to ensure that the obtained Mini-LED display module emits light evenly.

[0080] In some specific embodiments, a multi-layer circuit board substrate is provided, solder paste is printed on the first surface of the multi-layer circuit board substrate by printing, and the LED chip 2 with gold electrode is fixed on the substrate 1 by a single-point solid crystal process, and electrical conductivity is achieved by reflow soldering.

[0081] In step S02 , a bonding layer 3 is prepared on the first surface of the substrate 1 where no LED chip 2 is provided.

[0082] In some embodiments, the step of preparing the adhesive layer 3 on the first surface of the substrate 1 where the LED chip 2 is not set includes: providing raw materials for the adhesive layer 3, setting the raw materials for the adhesive layer 3 on the first surface of the substrate 1 where the LED chip 2 is not set by coating, spraying or soaking, and performing a curing treatment to obtain the adhesive layer 3.

[0083] In some specific embodiments, a black ink slurry is provided, and a layer of black ink is sprayed on the first surface of the substrate 1 where the LED chip 2 is not provided using an inkjet process to form a binding layer 3; a 365nm wavelength ultraviolet lamp is then used for pre-curing, and then an oven is used for post-curing at 150°C for 4 hours.

[0084] In step S03 , a first sealing layer 4 is prepared on the side of the LED chip 2 and the adhesive layer 3 facing away from the substrate 2 .

[0085] In some embodiments, the step of preparing the first sealing layer 4 on the side of the LED chip 2 and the adhesive layer 3 facing away from the substrate 2 includes: mixing the resin and glue additive material to obtain the raw material of the first sealing layer 4; setting the raw material of the first sealing layer 4 on the side of the LED chip 2 and the adhesive layer 3 facing away from the substrate 2 by printing, coating, dispensing or molding, and performing a curing treatment to obtain the first sealing layer 4.

[0086] In some embodiments, the curing temperature is 130-160° C., and the curing time is 3-5 hours.

[0087] In some specific embodiments, resin and glue additives are mixed to obtain the raw material of the first sealing layer 4; a semicircular shape of the raw material of the first sealing layer 4 is printed on the substrate 1 corresponding to each LED chip 2; and the raw material is cured in an oven at 150°C for 4 hours to obtain the first sealing layer 4.

[0088] In step S04 , a second sealing layer 5 is prepared on the side of the first sealing layer 4 away from the LED chip 2 and the adhesive layer 3 to obtain a Mini-LED display module.

[0089] In some embodiments, the step of preparing the second sealing layer 5 on the side of the first sealing layer 4 away from the LED chip 2 and the adhesive layer 3 includes: mixing resin and glue additives to obtain the raw material of the second sealing layer 5; setting the raw material of the second sealing layer 5 on the side of the first sealing layer 4 away from the LED chip 2 and the adhesive layer 3 by printing, coating, dispensing or molding, and performing a curing treatment to obtain the second sealing layer 5.

[0090] In some embodiments, the curing temperature is 130-160° C., and the curing time is 3-5 hours.

[0091] In some specific embodiments, resin and glue additives are mixed to obtain a raw material for the second sealing layer 5; the raw material for the second sealing layer 5 is pressed onto the first sealing layer 4 using a molding process, and then post-cured in an oven at 150°C for 4 hours to form the second sealing layer 5, and the excess portion at the edge is removed to obtain the second sealing layer 5.

[0092] A third aspect of an embodiment of the present application provides an electronic device, which includes a Mini-LED display module or a Mini-LED display module prepared by the method.

[0093] The electronic device provided in the third aspect of the embodiment of the present application includes a Mini-LED display module or a Mini-LED display module prepared by the method. Since the provided Mini-LED display module does not have a mosaic effect and white mura problem, the electronic device using the Mini-LED display module can significantly improve the display contrast and clarity, and is suitable for a wide range of applications.

[0094] The following describes the details in conjunction with specific embodiments.

[0095] Example 1

[0096] A Mini-LED display module, the preparation method comprising:

[0097] A multilayer circuit board substrate 1 is provided. Solder paste is printed on the multilayer circuit board substrate 1. A LED chip 2 with a gold electrode is fixed to the substrate 1 by single-point die bonding. Electrical conduction is achieved by reflow soldering.

[0098] Provide black ink, and use an inkjet process to spray a layer of black ink on the surface of the substrate 1 not covered by the LED chip 2 to form a binding layer 3. The black ink has a thickness of 30 μm and is pre-cured using a 365 nm wavelength ultraviolet lamp. Then, use an oven to post-cure at 150°C for 4 hours.

[0099] Providing raw materials for a first sealing layer 4, wherein the raw materials for the first sealing layer 4 include 90-99% of a resin having a refractive index of 1.4-1.8 and 1%-10% of a resin additive; wherein the resin is selected from epoxy resin, printing a semicircular shape of the first sealing layer 4 raw materials corresponding to each LED pixel unit on the substrate 1, and curing the first sealing layer 4 in an oven at 150°C for 4 hours to form the first sealing layer 4; the angle between the first sealing layer and the adhesive layer is 30°;

[0100] A raw material for a second sealing layer 5 is provided, wherein the raw material for the second sealing layer 5 includes 90% to 99% of a resin with a refractive index of 1.1 to 1.3 and 1% to 10% of a resin additive; wherein the resin is selected from epoxy resin, and a molding process is used to press the raw material for the second sealing layer 5 onto the first sealing layer 4 to form a second sealing layer 5, and the raw material is post-cured in an oven at 150°C for 4 hours, and excess portions at the edges are removed to form a second sealing layer 5; and a Mini-LED display module is obtained.

[0101] Example 2

[0102] A Mini-LED display module, the preparation method comprising:

[0103] A multilayer circuit board substrate 1 is provided. Solder paste is printed on the multilayer circuit board substrate 1. A LED chip 2 with a gold electrode is fixed to the substrate 1 by single-point die bonding. Electrical conduction is achieved by reflow soldering.

[0104] Provide black ink, and use an inkjet process to spray a layer of black ink on the surface of the substrate 1 not covered by the LED chip 2 to form a binding layer 3. The black ink has a thickness of 30 μm and is pre-cured using a 365 nm wavelength ultraviolet lamp. Then, use an oven to post-cure at 150°C for 4 hours.

[0105] Providing raw materials for a first sealing layer 4, wherein the raw materials for the first sealing layer 4 include 90-99% resin and 1%-10% diffusion powder, wherein the resin is selected from epoxy resin and the diffusion powder is selected from fumed silica; printing the raw materials for the first sealing layer 4 in a semicircular shape corresponding to each LED pixel unit on the substrate 1, and post-curing them in an oven at 150° C. for 4 hours to form the first sealing layer 4; the angle between the first sealing layer and the adhesive layer is 45°;

[0106] Providing raw materials for a second sealing layer 5, wherein the raw materials for the second sealing layer 5 include 95% to 99.5% of a resin and 0.5% to 5% of a colorant, wherein the resin is selected from an epoxy resin and the colorant is selected from carbon black; using a molding process to press the raw materials for the second sealing layer 5 onto the first sealing layer 4 to form a second sealing layer 5, post-curing in an oven at 150°C for 4 hours, and removing excess portions at the edges to form a second sealing layer 5; and obtaining a Mini-LED display module.

[0107] Example 3

[0108] A Mini-LED display module, the preparation method comprising:

[0109] A multilayer circuit board substrate 1 is provided. Solder paste is printed on the multilayer circuit board substrate 1. A LED chip 2 with a gold electrode is fixed to the substrate 1 by single-point die bonding. Electrical conduction is achieved by reflow soldering.

[0110] Provide black ink, and use an inkjet process to spray a layer of black ink on the surface of the substrate 1 not covered by the LED chip 2 to form a binding layer 3. The black ink has a thickness of 30 μm and is pre-cured using a 365 nm wavelength ultraviolet lamp. Then, use an oven to post-cure at 150°C for 4 hours.

[0111] Providing raw materials for a first sealing layer 4, wherein the raw materials for the first sealing layer 4 include 90-99% resin and 1%-10% quantum dot material, wherein the resin is selected from epoxy resin and the quantum dot material is selected from perovskite quantum dot material; printing the raw materials for the first sealing layer 4 in a semicircular shape corresponding to each LED pixel unit on the substrate 1, and post-curing in an oven at 150° C. for 4 hours to form the first sealing layer 4; the angle between the first sealing layer and the adhesive layer is 60°;

[0112] Providing raw materials for a second sealing layer 5, wherein the raw materials for the second sealing layer 5 include 90-99% resin and 1%-10% diffusion powder, wherein the resin is selected from epoxy resin and the diffusion powder is selected from barium sulfate; using a molding process to press the raw materials for the second sealing layer 5 onto the first sealing layer 4 to form a second sealing layer 5, post-curing in an oven at 150°C for 4 hours, and removing excess portions at the edges to form a second sealing layer 5; and obtaining a Mini-LED display module.

[0113] Comparative Example 1

[0114] A Mini-LED display module, the preparation method comprising:

[0115] A multilayer circuit board substrate 1 is provided. Solder paste is printed on the multilayer circuit board substrate 1. A LED chip 2 with a gold electrode is fixed to the substrate 1 by single-point die bonding. Electrical conduction is achieved by reflow soldering.

[0116] Provide black ink, and use an inkjet process to spray a layer of black ink on the surface of the substrate 1 not covered by the LED chip 2 to form a binding layer 3. The black ink has a thickness of 30 μm and is pre-cured using a 365 nm wavelength ultraviolet lamp. Then, use an oven to post-cure at 150°C for 4 hours.

[0117] Provide a first sealing layer 4 material, wherein the first sealing layer 4 material is epoxy resin, print the first sealing layer 4 material in a semicircular shape corresponding to each LED pixel unit on the substrate 1, and use an oven to post-curing at 150°C for 4 hours to form the first sealing layer 4;

[0118] Providing a raw material for a second sealing layer 5, wherein the raw material for the second sealing layer 5 is epoxy resin; using a molding process to press the raw material for the second sealing layer 5 onto the first sealing layer 4 to form a second sealing layer 5, using an oven to post-curing at 150°C for 4 hours, and removing excess edge portions to form a second sealing layer 5; and obtaining a Mini-LED display module.

[0119] Performance Testing

[0120] In order to verify the progress of the embodiments of the present application, the LED display modules prepared in the embodiments and comparative examples were tested as follows:

[0121] 1. Package luminous efficiency

[0122] The test method is as follows: First, use the CS2000 to test the unencapsulated light panel. The test data is the luminous brightness level 1, the test angle is 90° vertical, and the test distance is 50cm. After the light panel is encapsulated, use the same method and the same position to measure the luminous efficiency of the encapsulated layer. The luminous efficiency of the encapsulated layer is calculated by dividing the luminous efficiency of the encapsulated layer by the luminous efficiency of the encapsulated layer.

[0123] 2.LED display luminous angle

[0124] The test method is as follows: First, test the brightness of the display at a 90° vertical viewing angle. Continuously adjust the viewing angle with the display until the brightness reaches 1 / 2 of the vertical viewing angle. Record the angle at this point. This angle is the luminous angle of the LED display.

[0125] 3. Contrast of LED display

[0126] The test method is as follows: First, in a fixed brightness environment, output a full white screen to test its brightness, and then turn off the screen to test its brightness. The ratio of the two is the contrast ratio.

[0127] 4. Whether mosaic effect and white defect phenomenon occur

[0128] The test method is as follows: After assembling the display screen, visually observe at a 90° angle to see if there is obvious block-like color unevenness or white area.

[0129] Result Analysis

[0130] The LED display modules prepared in the embodiments and comparative examples were tested, and the results are shown in Table 1 below. It can be seen that the package luminous effects of the LED display modules obtained in Examples 1 to 3 are 78%, 83%, and 90%, respectively, while the package luminous effect of the LED display module obtained in Comparative Example 1 is 60%; the luminous angles of the LED display modules obtained in Examples 1 to 3 are 170°, 168°, and 165°, respectively, while the luminous angle of the LED display module obtained in Comparative Example 1 is 160°; the contrast ratios of the LED display modules obtained in Examples 1 to 3 are 25000:1, 28000:1, and 30000:1, respectively, while the contrast ratio of the LED display module obtained in Comparative Example 1 is 20000:1; the LED display modules obtained in Examples 1 to 3 do not exhibit mosaic effect and white defect phenomenon, while the LED display module obtained in Comparative Example 1 exhibits mosaic effect and white defect phenomenon. Mosaic effect phenomenon and white mura phenomenon; In summary, it can be seen that the Mini-LED display module provided by the present application, since the display module includes a first sealing layer and a second sealing layer, and the first sealing layer and the second sealing layer contain different glue additives, the glue additives include one or more of diffusion powder, colorant, quantum dot material, and resin additives; since the first sealing layer and the second sealing layer contain different glue additives, on the one hand, the material properties of the two sealing layers obtained are different, which causes the light to be refracted, thereby improving the luminous efficiency of the Mini-LED display module, increasing the light output angle of the LED chip, and improving the uniformity of mixed light; on the other hand, it can solve the problem of cross-light between LEDs, effectively improve the contrast of the LED display and increase the transmittance of the LED light, and solve the mosaic effect phenomenon and white mura problem that occur in the Mini-LED display module.

[0131] Table 1

[0132]

[0133] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A Mini-LED display module, characterized in that: The Mini-LED display module includes: substrate; a plurality of LED chips, wherein the LED chips are arranged on the first surface of the substrate; A bonding layer, the bonding layer is used for black shielding and is provided in a gap between the first surface of the substrate where the LED chip is not provided, wherein the bonding layer has a thickness of 20 to 70 μm; a first sealing layer, wherein the first sealing layer is arc-shaped and completely covers the LED chip and the adhesive layer; a second sealing layer, the second sealing layer being arranged on a side of the first sealing layer away from the LED chip and the adhesive layer and completely covering the first sealing layer; wherein the contact surface between the first sealing layer and the second sealing layer is a curved surface, the first sealing layer and the second sealing layer contain different glue additives, the first sealing layer includes 1% to 10% by weight of a resin additive with a refractive index of 1.4 to 1.8, and the second sealing layer includes 1% to 10% by weight of a resin additive with a refractive index of 1.1 to 1.3; and, The first sealing layer comprises 1% to 10% by weight of diffusion powder, and the second sealing layer comprises 0.5% to 5% by weight of colorant; or The first sealing layer includes 1% to 10% by mass of quantum dot material, and the second sealing layer includes 1% to 10% by mass of diffusion powder.

2. The Mini-LED display module according to claim 1, wherein: Taking the total mass of the first sealing layer or the second sealing layer as 100%, the raw material components include: 90-99.5% resin and 0.5-10% glue additive; wherein the resin includes at least one of epoxy resin, epoxy modified resin, silicone resin, and silicone modified resin.

3. The Mini-LED display module according to claim 1, wherein: The diffusion powder includes at least one of fumed silica, magnesium oxide, barium sulfate, and calcium carbonate; and / or, The colorant includes at least one of carbon black, graphene, carbon powder, carbon nanotubes, and black color paste; and / or, The quantum dot material includes at least one of a perovskite quantum dot material and a cadmium quantum dot material; and / or, The resin additive includes at least one resin additive having a refractive index of 1.1 to 1.8; and / or, The material of the adhesive layer includes at least one of polypropylene resin, black epoxy resin, black silicone resin, and black acrylic resin.

4. The Mini-LED display module according to any one of claims 1 to 3, wherein: The included angle between the first sealing glue layer and the binding layer is α, and α is 30°≤α<90°.

5. The Mini-LED display module according to any one of claims 1 to 3, wherein: The height of the LED chip is 80 to 100 μm. The thickness of the first sealing layer is 100-120 μm. The thickness of the second sealing layer is 150-300 μm.

6. A method for preparing a Mini-LED display module according to any one of claims 1 to 5, characterized in that: The following steps are involved: Providing a substrate, and fixing a plurality of LED chips on a first surface of the substrate; Prepare a bonding layer on the first surface of the substrate where the LED chip is not provided, Prepare a first sealing layer on the side of the LED chip and the adhesive layer facing away from the substrate; A second sealing layer is prepared on the side of the first sealing layer away from the LED chip and the adhesive layer to obtain a Mini-LED display module.

7. The method for preparing a Mini-LED display module according to claim 6, wherein: The step of preparing a binding layer on the first surface of the substrate where the LED chip is not provided includes: providing a binding layer raw material, applying the binding layer raw material to the first surface of the substrate where the LED chip is not provided by coating, spraying or soaking, and performing a curing treatment to obtain the binding layer; and / or The step of preparing a first sealing layer on the side of the LED chip and the adhesive layer facing away from the substrate includes: mixing a resin and a glue additive to obtain a first sealing layer raw material; placing the first sealing layer raw material on the side of the LED chip and the adhesive layer facing away from the substrate by printing, coating, dispensing or molding, and performing a curing process to obtain the first sealing layer; and / or, The step of preparing a second sealing layer on a side of the first sealing layer away from the LED chip and the adhesive layer includes: mixing a resin and a glue additive to obtain a second sealing layer raw material; placing the second sealing layer raw material on a side of the first sealing layer away from the LED chip and the adhesive layer by printing, coating, dispensing or molding, and performing a curing treatment to obtain the second sealing layer.

8. The method for preparing a Mini-LED display module according to claim 7, wherein: The temperature of the curing treatment is 130 to 160° C., and the time of the curing treatment is 3 to 5 hours.

9. An electronic device, characterized in that: The electronic device includes the Mini-LED display module described in any one of claims 1 to 5 or a Mini-LED display module prepared by the method for preparing a Mini-LED display module described in any one of claims 6 to 8.

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