An LED backlight module preparation method and an LED backlight module

Abstract

The application relates to an LED backlight module preparation method and an LED backlight module, which comprises the following steps: arranging a plurality of LED chips on the front surface of a substrate, preparing an encapsulating glue layer for sealing the LED chips, arranging a plurality of light diffusion units on the light emitting surface of the encapsulating glue layer at intervals by using optical glue prepared in advance, the light diffusion units reflect and refract the light emitted by the LED chips so that the light emitted by the LED chips can be uniformly emitted from the light emitting surface of the encapsulating glue layer, and the encapsulating glue layer is pressed onto the front surface of the substrate so that the encapsulating glue layer covers the LED chips, the plurality of light diffusion units are pressed into the encapsulating glue layer and are located above the LED chips. The backlight module prepared by the method can make the light diffusion units above the LED chips in the encapsulating glue layer emit the light emitted by the LED chips from the light emitting surface of the encapsulating glue layer uniformly, saves the light uniformizing film, reduces the overall thickness of the backlight module, and reduces the cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to an LED backlight module preparation method and an LED backlight module. BACKGROUND

[0002] The LED display screen can integrate information publishing, artistic entertainment and propaganda functions, and as a new high-tech product, it can add new vitality to the environment and build a moving landscape with its rich technological content, magnificent appearance, smooth display picture and delicate color performance.

[0003] With the continuous development of Mini LED products, the demand for thinness of smart terminal users for products such as tablets, notebook computers and displays gradually appears. The display module of the LED display screen is composed of a plurality of pixel units, so it is necessary to convert the point light source emitted by each pixel unit into a surface light source. In the related art, the conversion of the point light source into the surface light source is realized by optical films such as light uniformization films and diffusion films. Generally, 2 to 3 light uniformization films and diffusion film pieces are needed, which undoubtedly increases the overall thickness and cost of the display module, and cannot meet the demand of consumers for product performance.

[0004] Therefore, how to reduce the overall thickness and cost of the LED backlight module is a problem to be solved. SUMMARY

[0005] In view of the above problems of the related art, the purpose of the present application is to provide an LED backlight module preparation method and an LED backlight module, which aims to solve the problem of large overall thickness and high cost of the LED backlight module.

[0006] An LED backlight module preparation method comprises: arranging a plurality of LED chips on the front surface of a substrate;

[0007] An encapsulation glue layer is prepared for sealing the plurality of LED chips;

[0008] A plurality of light diffusion units are arranged on the light emitting surface of the encapsulation glue layer at intervals using pre-prepared optical glue, and the light diffusion units are used to reflect and refract the light emitted by the LED chips so that the light emitted by the plurality of LED chips is uniformly emitted from the light emitting surface of the encapsulation glue layer;

[0009] The encapsulation glue layer provided with the light diffusion units is laminated to the front surface of the substrate, so that the encapsulation glue layer covers each LED chip, and the plurality of light diffusion units are pressed into the encapsulation glue layer and located above the LED chips.

[0010] The LED backlight module preparation method comprises the following steps: setting a light diffusion unit on the light emitting surface of the encapsulation adhesive layer; and pressing the encapsulation adhesive layer provided with the light diffusion unit onto the front surface of the substrate, so that the light diffusion unit in the encapsulation adhesive layer reflects and refracts the light emitted by the LED chip, and the light emitted by the LED chip is uniformly emitted from the light emitting surface of the encapsulation adhesive layer, thereby saving the use of a light uniformizing film, reducing the overall thickness and cost of the backlight module, and simplifying the manufacturing process.

[0011] Optionally, before the step of uniformly setting a plurality of light diffusion units on the light emitting surface of the encapsulation adhesive layer using the optical adhesive prepared in advance, the method further comprises the following step: mixing light diffusion particles into a glue solvent according to a predetermined proportion to prepare the optical adhesive.

[0012] In the above method, the light diffusion particles are mixed into the glue solvent according to a predetermined proportion, thereby improving the light diffusion and light uniformizing performance of the light diffusion unit.

[0013] Optionally, the step of uniformly setting a plurality of light diffusion units on the light emitting surface of the encapsulation adhesive layer using the optical adhesive prepared in advance comprises one of the following modes:

[0014] the optical adhesive is used to form the light diffusion unit on the light emitting surface of the encapsulation adhesive layer through 3D printing;

[0015] the optical adhesive is used to form the light diffusion unit on the light emitting surface of the encapsulation adhesive layer through screen printing.

[0016] In the above method, the optical adhesive is used to form the light diffusion unit on the light emitting surface of the encapsulation adhesive layer through 3D printing or screen printing, and the manufacturing process is simple, and the shape of the light diffusion unit can be arbitrarily customized.

[0017] Based on the same inventive concept, the application further provides an LED backlight module, which comprises a substrate, a plurality of LED chips arranged on the front surface of the substrate, and an encapsulation adhesive layer arranged on the front surface of the substrate and covering the LED chips, wherein a region of the encapsulation adhesive layer away from the top surface of each LED chip is provided with a plurality of first light diffusion zones distributed at intervals, each first light diffusion zone comprises at least one light diffusion unit, the light diffusion unit comprises a light incident surface opposite to the top surface of the LED chip and a light emitting surface flush with the light emitting surface of the encapsulation adhesive layer, and the light diffusion unit is used to reflect and refract the light emitted by the LED chip, so that the light emitted by the plurality of LED chips is uniformly emitted from the light emitting surface of the encapsulation adhesive layer.

[0018] The light diffusion unit is arranged in the area away from the front face of the LED chip in the encapsulation glue layer, is used for reflecting and refracting the light emitted by the LED chip, and makes the light emitted by the LED chip uniformly emit from the light emitting surface of the encapsulation glue layer, thereby saving the use of the light uniformizing film, reducing the overall thickness and cost of the backlight module, and meanwhile, since the light diffusion unit is spaced apart from the chip by a certain distance, part of the light emitted by the chip can be reflected to the substrate and then reflected back to the encapsulation glue layer from the substrate, the first light diffusion area arranged at intervals can make the relatively weak light emitted through the substrate directly emit through the interval area between the first light diffusion areas arranged at intervals, improve the diffusion effect of the light, and reduce light loss; in addition, the first light diffusion area is arranged on the surface of the encapsulation glue layer, and customized design can be realized, different light intensity distributions of the light emitting surface are realized by arranging light diffusion units with different patterns, and different requirements of terminals are met.

[0019] Optionally, the light diffusion unit comprises a glue solvent and light diffusion particles mixed in the glue solvent according to a predetermined proportion.

[0020] The diffusion particles are mixed in the glue solvent according to a predetermined proportion, and the diffusion and light uniformizing performance of the light diffusion unit are improved.

[0021] Optionally, the first light diffusion area is located directly above the LED chip, and a projection area of the first light diffusion area on the front face of the substrate is greater than a projection area of the LED chip on the front face of the substrate.

[0022] The projection area of the first light diffusion area formed directly above the LED chip is greater than the projection area of the chip, so that most of the light emitted by the LED chip directly below the light diffusion unit in the first light diffusion area is refracted to the light emitting surface of the encapsulation glue layer.

[0023] Optionally, a projection shape of the first light diffusion area on the front face of the substrate comprises any one of a circle and a rectangle; the first diffusion area comprises a plurality of light diffusion units, and the light diffusion units are uniformly arranged at equal intervals.

[0024] The light diffusion units are uniformly distributed at equal intervals in the light diffusion area, the light emitting uniformity of the LED light on the encapsulation glue layer is improved, and particle clustering is reduced.

[0025] Optionally, a plurality of second light diffusion areas are arranged at intervals around the first light diffusion area, and the second light diffusion areas comprise at least one light diffusion unit.

[0026] A plurality of second light diffusion areas are arranged at intervals in the first light diffusion area, most of the light emitted by the LED chip is refracted to the light emitting surface of the encapsulation glue layer, and the light emitting uniformity of the LED light on the encapsulation glue layer is further improved.

[0027] Optionally, the second light diffusion regions are evenly distributed around the first light diffusion region at equal intervals, and the projection area of the second light diffusion regions on the front surface of the substrate is less than the projection area of the first light diffusion region on the front surface of the substrate.

[0028] Optionally, the melting point of the light diffusion unit is higher than the melting point of the encapsulation layer.

[0029] The melting point of the light diffusion unit is higher than the melting point of the encapsulation layer, so that the light diffusion unit will not be deformed due to heat when the encapsulation layer provided with the light diffusion unit is laminated to the substrate. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 A flow chart of a preparation method of an LED backlight module is provided for an embodiment of the present application.

[0031] Figure 2 A detailed flow chart of a preparation method of an LED backlight module is provided for an embodiment of the present application.

[0032] Figure 3 A side sectional view of an LED backlight module is provided for another embodiment of the present application.

[0033] Figure 4 A schematic diagram of a light uniformization process of a light diffusion unit on an LED chip is provided for another embodiment of the present application.

[0034] Figure 5 A schematic diagram of a projection structure of a light diffusion unit on a substrate is provided for another embodiment of the present application.

[0035] Figure 6 A schematic diagram of another projection structure of a light diffusion unit on a substrate is provided for another embodiment of the present application.

[0036] Figure 7-1 A schematic diagram of still another projection structure of a light diffusion unit on a substrate is provided for another embodiment of the present application.

[0037] Figure 7-2 A schematic diagram of still another projection structure of a light diffusion unit on a substrate is provided for another embodiment of the present application.

[0038] REFERENCE SIGNS:

[0039] 30 - substrate, 31 - LED chip, 32 - encapsulation layer, 33 - first light diffusion region, F - LED light, 34 - second light diffusion region, 331 - light diffusion unit. DETAILED DESCRIPTION

[0040] For the purpose of promoting an understanding of the application, the application will now be described in greater detail with reference to the figures. The preferred embodiments of the application are illustrated in the figures. However, the application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0042] In the related art, converting a point light source of a backlight module into a surface light source is achieved by using optical films such as a light uniformization film and a diffusion film. Generally, 2 to 3 pieces of light uniformization film and diffusion film are needed, which undoubtedly increases the overall thickness and cost of the display module, and cannot meet the demand of consumers for product performance.

[0043] Based on this, the present application hopes to provide a solution that can solve the above technical problems, and the detailed content will be described in the subsequent embodiments.

[0044] The embodiment of the present application provides a preparation method of an LED backlight module, referring to Figure 1 As shown in the figure, the method comprises the following steps:

[0045] S101: arranging a plurality of LED chips on the front surface of a substrate.

[0046] In this step, each LED chip is fixed on the front surface of the substrate, and each LED chip is uniformly distributed on the front surface of the substrate according to a preset array layout.

[0047] S102: preparing an encapsulation glue layer for sealing the plurality of LED chips.

[0048] The encapsulation glue layer is used to seal and protect the LED chips arranged on the front surface of the substrate.

[0049] S103: using a pre-prepared optical glue to arrange a plurality of light diffusion units on the light emitting surface of the encapsulation glue layer.

[0050] Before this step, the optical glue is prepared by mixing light diffusion particles into a glue solvent according to a predetermined proportion. This step can be performed before or after step S102, and then the optical glue is used to arrange the light diffusion units on the light emitting surface of the encapsulation glue layer. In this embodiment, the light diffusion particles include silicon dioxide and / or titanium dioxide, the glue solvent uses resin glue as the glue solvent, and the silicon dioxide and / or titanium dioxide are mixed into the glue solvent according to a predetermined proportion.

[0051] The array layout of each light diffusion unit on the light emitting surface of the encapsulating glue layer should be the same as the array layout of each LED chip on the front surface of the substrate, so that the light diffusion unit is just located above the LED chip. The light diffusion unit reflects and refracts the light emitted by the LED chip, so that the light emitted by each LED chip is uniformly emitted from the light emitting surface of the encapsulating glue layer, so that when the light emitted by the LED chip on the substrate is emitted from the light emitting surface of the encapsulating glue layer, the light emitting surface of the encapsulating glue layer is a uniform surface light source.

[0052] In this step of the embodiment, the light diffusion unit can be formed on the light emitting surface of the encapsulating glue layer by using 3D printing technology or screen silk printing technology.

[0053] S104: Press the encapsulating glue layer provided with the light diffusion unit to the front surface of the substrate.

[0054] After the light diffusion unit is arranged on the encapsulating glue layer, the encapsulating glue layer provided with the light diffusion unit is pressed to the front surface of the substrate. In the embodiment, the encapsulating glue layer provided with the light diffusion unit can be pressed to the substrate by using a hot pressing process, so that the encapsulating glue layer covers each LED chip, and the light diffusion unit is pressed into the protective glue layer above the LED chip, the upper surface of the light diffusion unit is located in the same plane as the light emitting surface of the encapsulating glue layer. It should be understood that in the embodiment, the melting point of the light diffusion unit is higher than the melting point of the encapsulating glue layer, and the encapsulating glue layer is pressed to the substrate by using the hot pressing process. In the hot pressing process, the light diffusion unit will not be deformed due to heating, and the encapsulating glue layer will cover each LED chip when the encapsulating glue layer reaches the melting point due to heating, and the light diffusion unit is pressed into the encapsulating glue layer. Therefore, in the case of keeping the overall thickness of the encapsulating glue layer unchanged, the light diffusion unit arranged above the LED chip in the encapsulating glue layer refracts and reflects the light emitted by the LED chip multiple times before emitting from the light emitting surface of the encapsulating glue layer, so that the light emitting surface of the encapsulating glue layer emits light uniformly, and there is no need to arrange a uniform light film on the encapsulating glue layer, avoiding the use of the uniform light film and reducing the overall thickness of the backlight module. Each light diffusion unit optically processes the light of a single LED chip, and the uniformity is good. Compared with using the uniform light film, the particle agglomeration phenomenon is avoided, and at the same time, the light emitting chip and the light diffusion unit are not in direct contact, so that the light emitted by the LED chip is reflected multiple times between the light diffusion unit and the front surface of the substrate before emitting from the encapsulating glue layer, reducing light loss.

[0055] This embodiment further includes, after step S104, setting an optical film layer on one side of the light-emitting surface of the encapsulating adhesive layer. The optical film layer includes a quantum film and a prism sheet, but does not include a light-diffusing film. In this embodiment, the light emitted by the LED chip is reflected and refracted by a light diffusion unit set in the encapsulating adhesive layer and then emitted out of the light-emitting surface of the encapsulating adhesive layer, thereby making the light-emitting surface of the encapsulating adhesive layer emit light uniformly. This replaces the use of a light-diffusing film on the encapsulating adhesive layer to uniformly emit light from the LED chip, eliminating the need for a light-diffusing film and reducing the overall thickness of the backlight.

[0056] This embodiment also provides another example of an LED backlight module fabrication method, see [link to relevant documentation]. Figure 2 As shown, the steps include:

[0057] S201: Several LED chips are disposed on the front side of the substrate.

[0058] In this step, each LED chip is fixed on the front side of the substrate, and the LED chips are evenly distributed on the front side of the substrate according to a preset array layout.

[0059] S202: To make an encapsulating adhesive layer for sealing several LED chips.

[0060] S203: Optical adhesive is prepared by mixing light-diffusing particles into an adhesive solvent in a predetermined ratio.

[0061] In this embodiment, the light-diffusing particles include silicon dioxide and / or titanium dioxide, and the adhesive solvent is a resin adhesive. Silicon dioxide and / or titanium dioxide are mixed into the adhesive solvent according to a predetermined ratio. In this embodiment, the order of steps S202 and S203 can be interchanged, or they can be performed simultaneously.

[0062] S204: Optical adhesive is printed onto the light-emitting surface of the encapsulating adhesive layer using 3D printing technology to form a light diffusion unit.

[0063] In this example, 3D printing technology is used to print optical adhesive onto the light-emitting surface of the encapsulating adhesive layer, forming a plurality of uniformly distributed light diffusion units. It should be understood that this embodiment can also use screen printing technology to screen-print the optical adhesive onto the light-emitting surface of the encapsulating adhesive layer to form light diffusion units. The array layout of each light diffusion unit on the light-emitting surface of the encapsulating adhesive layer should be the same as the array layout of each LED chip on the front side of the substrate, so that the optical structure is located exactly above the LED chip. The light diffusion units reflect and refract the light emitted by the LED chip, causing the light emitted by each LED chip to be uniformly emitted from the light-emitting surface of the encapsulating adhesive layer. Therefore, when the light emitted by the LED chip on the substrate is emitted from the light-emitting surface of the encapsulating adhesive layer, the light-emitting surface of the encapsulating adhesive layer is a uniformly emitting surface light source.

[0064] S205: Laminating the encapsulation adhesive layer provided with the light diffusion unit to the front surface of the substrate.

[0065] After printing the optical structure on the light-emitting surface of the encapsulation adhesive layer by the 3D printing technology, the encapsulation adhesive layer provided with the light diffusion unit is laminated to the front surface of the substrate.

[0066] S206: Providing an optical film layer on one side of the light-emitting surface of the encapsulation adhesive layer.

[0067] The optical film layer includes a quantum film and a prism sheet, but does not include a uniform light film. In this embodiment, the light emitted by the LED chip is reflected and refracted by the light diffusion unit provided in the encapsulation adhesive layer and then emitted from the light-emitting surface of the encapsulation adhesive layer, so that the light-emitting surface of the encapsulation adhesive layer emits light uniformly, thereby replacing the uniform light film provided on the encapsulation adhesive layer to uniformly light the light emitted by the LED chip, reducing the use of the uniform light film, and reducing the overall thickness of the backlight.

[0068] The embodiment of the present application provides a preparation method of an LED backlight module, which comprises the following steps: uniformly arranging a plurality of LED chips on the front surface of a substrate; preparing an encapsulation adhesive layer for sealing the LED chips; uniformly arranging a plurality of light diffusion units on the light-emitting surface of the encapsulation adhesive layer by using pre-prepared optical glue; the light diffusion units are used for reflecting and refracting the light emitted by the LED chips so that the light emitted by each LED chip can be uniformly emitted from the light-emitting surface of the encapsulation adhesive layer; laminating the encapsulation adhesive layer provided with the light diffusion units to the front surface of the substrate, so that the encapsulation adhesive layer covers the LED chips, and the plurality of light diffusion units are pressed into the encapsulation adhesive layer and located above the LED chips; and the backlight module prepared by the method of the present application is obtained. The light diffusion units above the LED chips in the encapsulation adhesive layer make the light emitted by the LED chips uniformly emitted from the light-emitting surface of the encapsulation adhesive layer, thereby saving the uniform light film, reducing the overall thickness of the backlight module, and reducing the cost of the backlight module.

[0069] Another embodiment of the present application is as follows:

[0070] Based on the same inventive concept, the embodiment of the present application provides an LED backlight module, which is used to solve the problem that the related art uses a uniform light film, a diffusion film and other optical films to realize the conversion of the point light source of the backlight module into a surface light source, thereby increasing the overall thickness and cost of the display module and failing to meet the demand of consumers for the performance-price ratio of products.

[0071] Based on this, the embodiment of the present application provides an LED backlight module, which comprises:

[0072] A substrate, the substrate in the embodiment of the present application comprises at least one of a PCB board, a glass substrate and a flexible substrate.

[0073] The LED chips disposed on the front surface of the substrate in the embodiment include at least one of red LED light-emitting chips, blue LED light-emitting chips, and green LED light-emitting chips. It should be understood that the LED chips in the embodiment can be micro light-emitting chips, for example, can include but are not limited to at least one of Mini LED chips and Micro LED chips, and can also be ordinary light-emitting chips with a size greater than or equal to 200 microns. And the LED chips in the embodiment can be normal mounting light-emitting chips, flip-chip light-emitting chips, or vertical light-emitting chips, or a mixture of different types of chips, which can be flexibly set according to application requirements. It should be understood that in the embodiment, the back surface of the substrate is also provided with a driving IC of the LED light-emitting chip to drive the operation of each LED chip.

[0074] The encapsulation glue layer disposed on the front surface of the substrate covers each LED chip. A region in the encapsulation glue layer away from the top surface of each LED chip forms a plurality of first light diffusion zones distributed at intervals. The first light diffusion zone includes at least one light diffusion unit. The light diffusion unit includes a light incident surface opposite to the top surface of the LED chip and a light exit surface flush with the light exit surface of the encapsulation glue layer. The light diffusion unit is used to reflect and refract the light emitted by the LED chip so that the light emitted by the LED chip is uniformly emitted from the light exit surface of the encapsulation glue layer.

[0075] For ease of understanding, the LED backlight module provided in the embodiment is exemplarily described below with reference to the accompanying drawings as examples.

[0076] An example of an LED backlight module is shown in Figure 3 The LED backlight module includes a substrate 30, a plurality of LED chips 31 uniformly distributed on the front surface of the substrate 30, and an encapsulation glue layer 32 disposed on the front surface of the substrate to cover each LED chip. A region in the encapsulation glue layer 32 away from the top surface of each LED chip forms a plurality of first light diffusion zones 33 distributed at intervals. The first light diffusion zone 33 includes at least one light diffusion unit 331. The light diffusion unit is composed of a glue solvent and light diffusion particles mixed in the glue solvent according to a predetermined proportion. In the embodiment, the first light diffusion zone 33 is located directly above the LED chip 31, and the projection area of the first light diffusion zone 33 on the front surface of the substrate is greater than the projection area of the LED chip on the front surface of the substrate.

[0077] In the embodiment, the light diffusion unit 331 on the first light diffusion zone 33 includes a light incident surface opposite to the top surface of the LED chip and a light exit surface flush with the light exit surface of the encapsulation glue layer. Referring to Figure 4As shown, the light F emitted by the LED is incident on the light incident surface of the light diffusion unit, and is reflected and refracted to be emitted from the light emitting surface of the light diffusion unit, so that the light emitted by the LED chip is uniformly emitted from the light emitting surface of the encapsulation adhesive layer, and each light diffusion unit respectively performs optical processing on the light of a single LED chip, and the uniformity is good. Compared with using a uniform light film, the particle clustering phenomenon is avoided, and at the same time, the LED chip is not in direct contact with the light diffusion unit, so that the light emitted from the top surface of the LED chip is reflected multiple times between the light diffusion unit and the front surface of the substrate and then emitted from the encapsulation adhesive layer, reducing light loss. The array layout of each light diffusion unit on the light emitting surface of the encapsulation adhesive layer should be the same as the array layout of each LED chip on the front surface of the substrate, so that the light diffusion unit is just located above the LED chip. The light diffusion unit reflects and refracts the light emitted by the LED chip, so that the light emitted by each LED chip is uniformly emitted from the light emitting surface of the encapsulation adhesive layer, so that when the light emitted by the LED chip on the substrate is emitted from the light emitting surface of the encapsulation adhesive layer, the light emitting surface of the encapsulation adhesive layer is a uniform light emitting surface light source.

[0078] It should be understood that the backlight module in the embodiment further includes an optical film layer arranged on one side of the light emitting surface of the encapsulation adhesive layer, and the optical film layer includes a quantum film, a prism sheet, but does not include a uniform light film. In the present embodiment, the light diffusion unit arranged in the encapsulation adhesive layer reflects and refracts the light emitted by the LED chip and then emits the light from the light emitting surface of the encapsulation adhesive layer, so that the light emitting surface of the encapsulation adhesive layer emits light uniformly, replacing the arrangement of the uniform light film on the encapsulation adhesive layer to perform uniform light on the light of the LED chip, eliminating the use of the uniform light film, and reducing the overall thickness of the backlight.

[0079] In the present embodiment, the optical glue is made of a glue solvent and light diffusion particles mixed in the glue solvent according to a predetermined proportion, the light diffusion particles include at least one of silicon dioxide and / or titanium dioxide, and the shape of the light diffusion particles includes any one of a circle, a square, and a triangle, and can also be other irregular shapes, which can be flexibly set according to actual application. After the optical glue is made, the optical glue is printed on the light emitting surface of the encapsulation adhesive layer by 3D printing technology or is screen printed on the first light diffusion area on the light emitting surface of the encapsulation adhesive layer by screen printing technology to form the light diffusion unit. Then, the encapsulation adhesive layer with the light diffusion unit is pressed onto the front surface of the substrate by a hot pressing process, so that the LED chip arranged on the front surface of the substrate is covered in the encapsulation adhesive layer, and at the same time, the light diffusion unit on the light emitting surface of the encapsulation adhesive layer is pressed into the encapsulation adhesive layer and located above the LED chip. The upper surface of the light diffusion unit is in the same plane as the light emitting surface of the encapsulation adhesive layer. It should be understood that in the present embodiment, the projection area of the light diffusion unit on the front surface of the substrate is larger than the projection area of the LED chip on the front surface of the substrate, so that the light diffusion unit can reflect or refract most of the light emitted by the LED chip.

[0080] In this embodiment, the light uniformization effect of the light diffusion unit is related to the shape, thickness of the light diffusion unit and the proportion of the light diffusion particles in the light diffusion unit. Different light uniformization effects can be achieved by setting different shapes, thicknesses and proportions of light diffusion particles of the light diffusion unit. In this embodiment, taking silica as the light diffusion particles as an example, the proportion of silica in the optical glue is determined according to the LED pitch value (i.e. the spacing value between LED chips, such as shown in FIG. 3) and the thickness of the light diffusion unit. According to the index of the light leakage ratio of the Mini backlight product, the light of one lamp area should be as little as possible to escape to other lamp areas. Therefore, the proportion of silica is positively correlated with the LED pitch value and negatively correlated with the thickness of the light diffusion unit. The LED pitch value and the thickness of the light diffusion unit are set according to actual needs. In this embodiment, the proportion of silica = 30% + [(LED pitch-3.0) / 0.2-(light diffusion unit thickness-20) / 10]*10%. See Table 1 for several groups of silica proportion, LED pitch value and light diffusion unit thickness data obtained according to the relationship. Figure 3

[0081]

[0082] (Table 1)

[0083] In this embodiment, the shape of the light diffusion unit can include any one of a circle, a rectangle and a triangle. In an example, as shown in FIG. 3, only one light diffusion unit is arranged in the first light diffusion area 33, which fills the entire first light diffusion area, and the shape of the light diffusion unit is a circle. In this embodiment, the shape of the light diffusion unit refers to the shape of the light diffusion unit projected on the front surface of the substrate. It should be understood that the shape of the light diffusion unit is not limited to the above examples, but can be any other shape, which can be flexibly set according to actual needs. In this embodiment, the projection area of the light diffusion unit on the front surface of the substrate should be greater than the projection area of the LED chip on the front surface of the substrate. Figure 5

[0084] In this embodiment, the first light diffusion area 33 can also include a plurality of light diffusion units. The plurality of light diffusion units form the first light diffusion area according to a preset arrangement rule. As shown in FIG. 4, the first light diffusion area 33 includes a plurality of light diffusion units 331, which are arranged at equal intervals in the first light diffusion area. In this embodiment, the plurality of light diffusion units are evenly distributed at equal intervals. Of course, the plurality of light diffusion units can also be distributed according to other arrangement rules. The shape of the light diffusion unit can include any one of a circle, a rectangle and a triangle, which can be flexibly set according to actual needs. Figure 6

[0085] ​​​In the embodiment, a plurality of second light diffusion zones can be arranged around the first light diffusion zone, each second light diffusion zone includes at least one light diffusion unit, and each second light diffusion zone is distributed around the first light diffusion zone according to a preset rule. In the embodiment, each second light diffusion zone is evenly distributed around the first light diffusion zone at equal intervals. It should be understood that each second light diffusion zone can also be distributed around the second light diffusion zone according to other arrangement rules, which can be flexibly set according to actual application requirements. It should be understood that in the embodiment, the projection of the second light diffusion zone on the substrate is smaller than the projection area of the first light diffusion zone on the substrate.

[0086] In an example, referring to FIG. 3, eight second light diffusion zones 34 are arranged around the first light diffusion zone 33. One light diffusion unit is arranged in the first light diffusion zone 33, and one light diffusion unit is arranged in each second light diffusion zone 34. Each second light diffusion zone 34 is arranged at equal intervals on the circumference of the first light diffusion zone 33. Figure 7-1

[0087] In another example, referring to FIG. 4, eight second light diffusion zones 34 are arranged around the first light diffusion zone 33. A plurality of light diffusion units 331 are arranged in the first light diffusion zone 33, and a plurality of light diffusion units are arranged in each second light diffusion zone 34. The plurality of light diffusion units in the first light diffusion zone and the second light diffusion zone are evenly arranged at equal intervals. Figure 7-2

[0088] The LED backlight module provided by the embodiment of the application includes a substrate, a plurality of LED chips evenly distributed on the front surface of the substrate, and an encapsulation adhesive layer arranged on the front surface of the substrate and covering the LED chips. A plurality of first light diffusion zones are arranged at intervals in the region of the encapsulation adhesive layer away from the top surface of the LED chip. The first light diffusion zone includes at least one light diffusion unit. The light diffusion unit includes a light incident surface opposite to the top surface of the LED chip and a light emission surface flush with the light emission surface of the encapsulation adhesive layer. The light diffusion unit is used for reflecting or refracting the light emitted by the LED chip so that the light emitted by the plurality of LED chips is uniformly emitted from the light emission surface of the encapsulation adhesive layer. In the LED backlight module, the light diffusion unit is arranged in the region of the encapsulation adhesive layer away from the top surface of the LED chip, which is used for reflecting or refracting the light emitted by the LED chip so that the light emitted by the LED chip is uniformly emitted from the light emission surface of the encapsulation adhesive layer. Therefore, the use of the light uniformization film is saved, and the overall thickness and cost of the backlight module are reduced.

[0089] ​​The LED backlight module structure provided in the foregoing embodiments can be applied to various display fields, for example, can be a backlight module of a terminal such as a television, a display, a mobile phone, and the like. At this time, it can be applied to a backlight module. In addition to being applicable to the display backlight field, it can also be applied to the decoration field, the automobile field, the transportation field, and the like.

[0090] It should be understood that the application of the present application is not limited to the above examples, and can be improved or changed by those of ordinary skill in the art according to the above description, and all such improvements and changes shall fall within the protection scope of the claims of the present application.

Claims

1. A method for manufacturing an LED backlight module, characterized in that, include: Several LED chips are disposed on the front side of the substrate; Prepare an encapsulating adhesive layer for sealing the plurality of LED chips; A plurality of first light diffusion regions are uniformly disposed on the light-emitting surface of the encapsulating adhesive layer using a pre-prepared optical adhesive. Each first light diffusion region includes at least one light diffusion unit, which is used to reflect and refract the light emitted by the LED chip so that the light emitted by the plurality of LED chips is uniformly emitted from the light-emitting surface of the encapsulating adhesive layer. The encapsulating adhesive layer containing the light diffusion units is pressed onto the front side of the substrate, so that the encapsulating adhesive layer covers each of the LED chips, and the plurality of light diffusion units are pressed into the encapsulating adhesive layer and located above the LED chips. The melting point of the light diffusion unit is higher than that of the encapsulating adhesive layer. The encapsulating adhesive layer is pressed onto the substrate using a hot pressing process, so that the encapsulating adhesive layer covers each of the LED chips. The light diffusion unit is pressed into the encapsulating adhesive layer so that the surface of the light diffusion unit and the light emitting surface of the encapsulating adhesive layer are on the same plane. Each of the LED chips is provided with a corresponding first light diffusion region, and each light diffusion unit can perform optical processing on the light from a single LED chip. A second light diffusion region is provided at intervals around the first light diffusion region, and the second light diffusion region includes at least one of the light diffusion units, so that the second light diffusion region can refract light around the first light diffusion region; The first light diffusion region is provided with a plurality of light diffusion units, and each of the second light diffusion regions is provided with a plurality of light diffusion units.

2. The method for manufacturing an LED backlight module as described in claim 1, characterized in that, Before uniformly setting a plurality of light diffusion units on the light-emitting surface of the encapsulating adhesive layer using pre-prepared optical adhesive, the method further includes: The optical adhesive is prepared by mixing light-diffusing particles into an adhesive solvent in a predetermined ratio.

3. The method for manufacturing an LED backlight module as described in claim 2, characterized in that, The method of uniformly distributing a plurality of light diffusion units on the light-emitting surface of the encapsulating adhesive layer using pre-prepared optical adhesive includes one of the following: The optical adhesive is 3D printed onto the light-emitting surface of the encapsulating adhesive layer to form the light diffusion unit; The optical adhesive is screen-printed onto the light-emitting surface of the encapsulating adhesive layer to form the light diffusion unit.

4. An LED backlight module, characterized in that, include: A substrate, a plurality of LED chips disposed on the front side of the substrate, and an encapsulating adhesive layer covering each LED chip by hot pressing onto the front side of the substrate. A plurality of spaced first light diffusion regions are formed in the region of the encapsulating adhesive layer away from the top surface of the LED chips. The first light diffusion regions are disposed in the encapsulating adhesive layer by pressing. Each first light diffusion region includes at least one light diffusion unit. The light diffusion unit includes a light incident surface opposite to the top surface of the LED chip and a light emitting surface flush with the light emitting surface of the encapsulating adhesive layer. The light diffusion unit is used to reflect and refract the light emitted by the LED chip so that the light emitted by the LED chip is uniformly emitted from the light emitting surface of the encapsulating adhesive layer. The melting point of the light diffusion unit is higher than that of the encapsulating adhesive layer, so that the light diffusion unit will not deform due to heat during hot pressing. The surface of the light diffusion unit and the light-emitting surface of the encapsulating adhesive layer are located on the same plane. Each of the LED chips is provided with a corresponding first light diffusion region, and each light diffusion unit can perform optical processing on the light from a single LED chip. The LED backlight module further includes a plurality of second light diffusion regions spaced apart around the first light diffusion region. Each second light diffusion region includes at least one light diffusion unit, such that the second light diffusion region can refract light around the first light diffusion region. The first light diffusion region is provided with a plurality of light diffusion units, and each of the second light diffusion regions is provided with a plurality of light diffusion units.

5. The LED backlight module as described in claim 4, characterized in that, The light diffusion unit includes: an adhesive solvent and light diffusion particles mixed into the adhesive solvent in a predetermined ratio.

6. The LED backlight module as described in claim 4, characterized in that, The first light diffusion region is located directly above the LED chip, and its projected area on the front side of the substrate is larger than the projected area of ​​the LED chip on the front side of the substrate.

7. The LED backlight module as described in any one of claims 4-6, characterized in that, The projection shape of the first light diffusion region on the front side of the substrate includes either a circle or a rectangle; the first light diffusion region includes a plurality of light diffusion units, and each light diffusion unit is evenly arranged at equal intervals.

8. The LED backlight module as described in any one of claims 4-6, characterized in that, Each of the second light diffusion regions is evenly distributed around the first light diffusion region at equal intervals, and its projected area on the front side of the substrate is smaller than the projected area of ​​the first light diffusion region on the front side of the substrate.

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