Backlight module

Abstract

The utility model discloses a backlight module, which relates to the technical field of liquid crystal display, and comprises a plastic-iron integrated frame body, a reflector plate, a light guide plate, an optical film material and shading glue are sequentially laminated in the frame body from bottom to top, the shading glue is adhered to the upper surface of the frame body, and the light guide plate is arranged on the upper surface of the frame body. A diffusion film, a lower brightness enhancement film and an upper brightness enhancement film are sequentially stacked on the optical film material from bottom to top, and a shading ink layer is arranged on the surface of one end of the diffusion film in a silk-screen printing mode. According to the backlight module provided by the utility model, the light rays emitted by the tail part of the light guide plate are shielded by silk-screening the shading ink layer at the tail part of the diffusion film of the light ray film material, so that the problem of bright lines at the tail part of a display area is solved, the display effect of a screen is improved, the reject ratio of the backlight module is reduced, the product competitiveness is improved, and the production cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of liquid crystal display technology, and in particular to a backlight module. Background Technology

[0002] With the rapid development of technology, smartphones with high screen-to-body ratios have gradually become the mainstream in the market. Smartphones with high screen-to-body ratios require backlight modules with narrow bezels. The most common problem with backlight modules with narrow bezels is light leakage.

[0003] Chinese patent application number 202222332290.2 discloses a backlight module that prevents light leakage, which includes an integrally molded lower frame. The lower frame includes a base plate, a side wall extending upward from the edge of the base plate, and a glue frame disposed on the base plate and abutting against the side wall. A reflective sheet, a light guide plate, an optical film group, and a light-shielding adhesive are sequentially stacked on the base plate from bottom to top. The light-shielding adhesive is adhered to the upper surface of the glue frame. The upper surface of the glue frame has multiple grooves arranged in parallel. The adhesion strength between the light-shielding adhesive and the glue frame is improved by setting grooves on the glue frame.

[0004] Chinese patent application number 202220473364.1 discloses a narrow-bezel backlight module, which includes a lower frame, a reflective sheet, a light guide plate, an optical film assembly, and a light-shielding adhesive. The lower frame includes a base plate, a first sidewall, a second sidewall, and a third sidewall. The first sidewall is bent upward from the edge of the base plate, the second sidewall is bent outward from the edge of the first sidewall, and the third sidewall is bent downward from the edge of the second sidewall. The reflective sheet is fixed to the base plate; the light guide plate is fixed to the reflective sheet; the optical film assembly is fixed to the light guide plate; and the light-shielding adhesive is disposed on the optical film assembly and the second sidewall. By bending the second sidewall outward, the light-shielding adhesive can be disposed on the optical film assembly and the second sidewall, achieving adhesion and fixation without the need for an integrated glue-iron structure, thereby preventing foreign objects from entering the backlight module from the side.

[0005] Existing backlight modules use light-blocking adhesive to prevent light leakage. However, uneven backlight distribution and light source position can cause bright lines to appear at the end of the display area, affecting screen display quality, increasing defect rate, and reducing product competitiveness. Therefore, this utility model discloses a backlight module that solves the above problems. Utility Model Content

[0006] Therefore, it is necessary to provide a backlight module that addresses the aforementioned technical problems by screen-printing a light-shielding ink layer at the end of the light diffusion film to block the light emitted from the end of the light guide plate, thereby solving the problem of bright lines at the end of the display area, improving the screen display effect, reducing the defect rate of the backlight module, enhancing product competitiveness, and reducing production costs.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] A backlight module includes a frame made of glue and iron. A reflective sheet, a light guide plate, an optical film and a light-shielding adhesive are stacked in sequence from bottom to top in the frame. The light-shielding adhesive is bonded to the upper surface of the frame. The optical film includes a diffusion film, a lower brightness enhancement film and an upper brightness enhancement film stacked in sequence from bottom to top. A light-shielding ink layer is screen-printed on one end of the diffusion film.

[0009] In a preferred embodiment of the backlight module provided by this utility model, the frame includes a plastic frame and an iron frame. The iron frame includes a base plate and a side wall. The plastic frame is disposed on the base plate and abuts against the side wall. The height of the plastic frame is greater than the height of the side plate and the plastic frame extends to cover the top surface of the side wall.

[0010] In a preferred embodiment of the backlight module provided by this utility model, the light-shielding ink layer is disposed at the position where bright lines are generated in the display area of ​​the backlight module.

[0011] In a preferred embodiment of the backlight module provided by this utility model, the light-shielding ink layer is a black ink layer.

[0012] In a preferred embodiment of the backlight module provided by this utility model, the width of the light-shielding ink layer is 0.25 mm and the thickness is 0.01 mm.

[0013] In a preferred embodiment of the backlight module provided by this utility model, the diffusion film has a glossy surface and a matte surface. The glossy surface of the diffusion film is bonded to the light guide plate, and the matte surface of the diffusion film is bonded to the lower brightness enhancement film.

[0014] In a preferred embodiment of the backlight module provided by this utility model, the light-shielding ink layer is disposed on the matte surface of the diffusion film.

[0015] In a preferred embodiment of the backlight module provided by this utility model, the light-shielding adhesive is located above the light-shielding ink layer and can cover the light-shielding ink layer.

[0016] In a preferred embodiment of the backlight module provided by this utility model, one end edge of the reflective sheet is bent upward to form a bent edge, and the bent edge is attached to the side of the light guide plate.

[0017] In a preferred embodiment of the backlight module provided by this utility model, a gap is left between the bent edge of the reflective sheet and the inner wall of the frame, and an elastic body is provided in the gap, with the two sides of the elastic body abutting against the bent edge and the inner wall of the frame, respectively.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The backlight module provided by the present invention blocks the light emitted from the tail of the light guide plate by screen printing a light-shielding ink layer at the tail of the light diffusion film, thereby solving the problem of bright lines at the tail of the display area, improving the display effect of the screen, reducing the defect rate of the backlight module, improving product competitiveness, and reducing production costs. Attached Figure Description

[0019] To more clearly illustrate the solutions in this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 A schematic diagram of the overall structure of the backlight module provided by this utility model;

[0021] Figure 2 A schematic diagram of the diffusion film in the backlight module provided by this utility model;

[0022] Figure 3 A schematic diagram of a structure of the backlight module provided by this utility model in Embodiment 3;

[0023] Figure 4 This is a schematic diagram of another structure in Embodiment 3 of the backlight module provided by this utility model.

[0024] The markings in the diagram are explained as follows:

[0025] 1. Frame; 2. Iron frame; 21. Base plate; 22. Side wall; 3. Reflective sheet; 31. Bending edge; 4. Light guide plate; 5. Diffuser film; 51. Glossy surface; 52. Matte surface; 6. Lower brightness enhancement film; 7. Upper brightness enhancement film; 8. Light-shielding adhesive; 9. Light-shielding ink layer; 10. Void; 11. Elastomer. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0027] As described in the background section, uneven distribution of backlight sources and their positions can cause bright lines to appear at the tail of the display area of ​​the backlight module, affecting the screen display effect, increasing the defect rate, and reducing product competitiveness.

[0028] To solve this technical problem, this utility model provides a backlight module that is applied in the field of liquid crystal display technology.

[0029] For details, please refer to Figure 1-4 The backlight module specifically includes a frame made of glue and iron. A reflective sheet 3, a light guide plate 4, an optical film and a light-shielding adhesive 8 are stacked in sequence from bottom to top in the frame. The light-shielding adhesive 8 is bonded to the upper surface of the frame. A diffusion film 5, a lower brightness enhancement film 6 and an upper brightness enhancement film 7 are stacked in sequence from bottom to top in the optical film. A light-shielding ink layer 9 is screen-printed on one end of the diffusion film 5.

[0030] The backlight module provided by this utility model blocks the light emitted from the tail of the light guide plate 4 by screen printing a light-shielding ink layer 9 on the tail of the light diffusion film 5, thereby solving the problem of bright lines at the tail of the display area, improving the display effect of the screen, reducing the defect rate of the backlight module, improving product competitiveness, and reducing production costs.

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0032] It should be noted that, unless otherwise specified, the embodiments and features and technical solutions in the present invention can be combined with each other.

[0033] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0034] Example 1

[0035] In narrow bezel designs, the backlight is usually concentrated at the edge of the screen, which may lead to uneven light distribution. At the rear of the display area, especially in areas farther from the light source, the light may not propagate evenly, resulting in bright lines. Secondly, the light source of the backlight module (such as LED strips) may attenuate with increasing distance, causing excessive brightness at the rear of the screen, thus forming obvious bright lines.

[0036] Please refer to Figure 1-2 A backlight module is provided, which includes a frame made of glue and iron. The frame includes a glue frame 1 and an iron frame 2. The iron frame 2 includes a base plate 21 and a side wall 22. The edge of the base plate 21 is bent upward to form the side wall 22. The glue frame 1 is disposed on the base plate 21 and abuts against the side wall 22. The height of the glue frame 1 is greater than the height of the side plate and the glue frame 1 extends to cover the top surface of the side wall 22. The outer surface of the glue frame 1 is flush with the outer surface of the side wall 22. The iron frame 2 and the glue frame 1 are integrally formed to form an integral structure, which improves the connection between the glue frame 1 and the iron frame 2, reduces the assembly process, and thus reduces the production cost.

[0037] A reflective sheet 3, a light guide plate 4, an optical film, and a light-shielding adhesive 8 are stacked sequentially from bottom to top on the base plate 21 of the iron frame 2. The light-shielding adhesive 8 is bonded to the upper surface of the frame. The optical film consists of a diffusion film 5, a lower brightness enhancement film 6, and an upper brightness enhancement film 7 stacked sequentially from bottom to top. One end of the diffusion film 5, the lower brightness enhancement film 6, and the upper brightness enhancement film 7 are flush. A light-shielding ink layer 9 is screen-printed on the surface of the diffusion film 5 at the tail end of the light guide plate 4. The light-shielding ink layer 9 is located in the display area of ​​the backlight module. The location of the bright line is at the tail of the light guide plate 4, which is the display area of ​​the backlight module where the bright line is generated. The tail of the light guide plate 4 is a broad concept, which in mobile phones is the bottom when the phone is used vertically. In this example, the tail of the light guide plate 4 is the end away from the backlight. Of course, a light-shielding ink layer 9 can be set at other locations in the display area where bright lines are generated (i.e., the locations where the light guide plate 4 is too bright). The light-shielding ink layer 9 blocks the light emitted from the tail of the light guide plate 4, thereby solving the problem of bright lines at the tail of the display area.

[0038] In this example, the light-shielding ink layer 9 is a black ink layer with a width of 0.25mm and a thickness of 0.01mm. The light-shielding adhesive 8 is located above the light-shielding ink layer 9 and can cover the light-shielding ink layer 9. This can completely solve the problems of light leakage and bright lines at the tail of the smartphone, improve the display effect of the smartphone, increase user satisfaction, and thus enhance market competitiveness.

[0039] The light-shielding ink layer 9 is made of black ink using a screen printing stencil. During preparation, the black ink can be screen printed on any side of the end of the diffusion film 5.

[0040] Example 2

[0041] The backlight module provided in Example 1 is further optimized, specifically, as follows: Figure 1-2 As shown, the diffusion film 5 has a glossy surface 51 and a matte surface 52. The glossy surface 51 of the diffusion film 5 is bonded to the light guide plate 4, and the matte surface 52 of the diffusion film 5 is bonded to the lower brightness enhancement film 6. The light-shielding ink layer 9 is disposed at one end of the matte surface 52 of the diffusion film 5. When the light-shielding ink layer 9 is disposed at one end of the glossy surface 51 of the diffusion film 5, the screen printing process is: slitting, printing, lamination, punching, and die-cutting. When the light-shielding ink layer 9 is disposed at one end of the matte surface 52 of the diffusion film 5, the screen printing process is: slitting, printing, punching, and die-cutting. A comparison of the two screen printing processes shows that when the light-shielding ink layer 9 is disposed at one end of the matte surface 52 of the diffusion film 5, one lamination process and one protective film can be saved, thereby reducing labor and material costs.

[0042] Example 3

[0043] The backlight module provided in Example 2 is further optimized, specifically, as follows: Figure 3 As shown, one edge of the reflective sheet is bent upward to form a bent edge 31, which is attached to the side of the light guide plate 4. The height of the bent edge 31 is consistent with the thickness of the light guide plate 4 on the corresponding attached side, so that the bent edge 31 can completely cover the side of the light guide plate 4. The bent edge 31 of the reflective sheet is used to block the light on the side of the light guide plate 4 to improve the utilization rate of the light emitted by the light source, and at the same time, it can further prevent light leakage.

[0044] like Figure 4 As shown, a gap 10 is left between the bent edge 31 of the reflector and the inner wall of the frame. An elastic body 11 is provided in the gap 10. The two sides of the elastic body 11 abut against the bent edge 31 and the inner wall of the frame, respectively. The setting of the elastic body 11 can, on the one hand, keep the bent edge of the reflector in close contact with the side of the light guide plate 4, and prevent the bent edge from falling off the side of the light guide plate 4. On the other hand, it can buffer the impact force of the light guide plate 4 on the frame when the smartphone is hit or vibrated, so as to avoid the light guide plate 4 colliding with the frame and causing noise. It can also improve the service life of the light guide plate 4.

[0045] The elastomer 11 is a rubber body. The structure of the elastomer 11 can be any structure, but the height of the elastomer 11 does not exceed the thickness of the light guide plate 4. In order to improve the buffering function, a number of air holes can be provided inside the elastomer 11. The shape of the air holes can be spherical, prism, or other shapes, which are not limited here. The interior of the elastomer 11 can also be set in a honeycomb shape.

[0046] The working principle of the backlight module provided by this utility model is as follows: A frame body consisting of a plastic frame 1 and an iron frame 2 is prepared. Inside the frame body, a reflective sheet, a light guide plate 4, and an optical film material are sequentially bonded and fixed from bottom to top, along with other accessories required for the backlight module, such as a backlight source. A light-shielding ink layer 9 is screen-printed on the diffuser film 5 of the optical film material away from the matte surface 52 of the light guide plate 4. The screen printing is performed using a screen printing stencil structure. By screen-printing the light-shielding ink layer 9 at the tail of the diffuser film 5 of the light film material, the light emitted from the tail of the light guide plate 4 is blocked, thereby solving the problem of bright lines at the tail of the display area, improving the display effect of the screen, reducing the defect rate of the backlight module, increasing product competitiveness, and reducing production costs.

[0047] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0048] Obviously, the embodiments described above are only some embodiments of this utility model, not all embodiments. The accompanying drawings show preferred embodiments of this utility model, but do not limit the patent scope of this utility model. This utility model can be implemented in many different forms; conversely, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the disclosure of this utility model. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing specific embodiments, or make equivalent substitutions for some of the technical features. Any equivalent structures made using the content of this utility model specification and drawings, directly or indirectly applied to other related technical fields, are similarly within the patent protection scope of this utility model.

Claims

1. A backlight module comprising a frame made of glue and iron, wherein a reflective sheet, a light guide plate, an optical film, and a light-shielding adhesive are sequentially stacked from bottom to top within the frame, the light-shielding adhesive being bonded to the upper surface of the frame, characterized in that, The optical film material is provided with a diffusion film, a lower brightness enhancement film and an upper brightness enhancement film stacked from bottom to top. One end of the diffusion film is screen-printed with a light-shielding ink layer. One end of the reflective sheet is bent upward to form a bent edge. The bent edge is attached to the side of the light guide plate. A gap is left between the bent edge of the reflective sheet and the inner wall of the frame. An elastic body is provided in the gap. The two sides of the elastic body abut against the bent edge and the inner wall of the frame, respectively.

2. A backlight module according to claim 1, characterized in that, The frame includes a plastic frame and an iron frame. The iron frame includes a base plate and a side wall. The plastic frame is disposed on the base plate and abuts against the side wall. The height of the plastic frame is greater than the height of the side plate and the plastic frame extends to cover the top surface of the side wall.

3. A backlight module according to claim 1, characterized in that, The light-shielding ink layer is located at the position where bright lines are generated in the display area of ​​the backlight module.

4. A backlight module according to claim 1, characterized in that, The light-shielding adhesive is located above the light-shielding ink layer and can cover the light-shielding ink layer.

5. A backlight module according to claim 1, characterized in that, The light-shielding ink layer is a black ink layer.

6. A backlight module according to claim 5, characterized in that, The width of the light-shielding ink layer is 0.25 mm and the thickness is 0.01 mm.

7. A backlight module according to claim 1, characterized in that, The diffusion film has a glossy surface and a matte surface. The glossy surface of the diffusion film is bonded to the light guide plate, and the matte surface of the diffusion film is bonded to the lower brightness enhancement film.

8. A backlight module according to claim 7, characterized in that, The light-shielding ink layer is disposed on the frosted surface of the diffusion film.

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