Backlight structure for reducing light at hole position and liquid crystal display device thereof

Abstract

The embodiment of the utility model provides a backlight structure capable of reducing light at a hole position and a liquid crystal display device thereof, the backlight structure comprises a hole fixing device and an optical module, the optical module comprises a light guide plate, a diffusion film and a prism film group which are sequentially arranged along a light emitting direction, and the light guide plate and the diffusion film in the optical module are respectively provided with a mounting hole; the mounting hole is provided with a hole fixing device for positioning and mounting the camera module; the prism film group is not provided with a prism structure at the orthogonal projection position of the hole fixing device, and is not provided with a lateral light incident surface, so that side light leakage is reduced. The prism film has no lateral light incident surface at the orthogonal projection position of the hole fixing device, so that light emitted at the camera mounting hole position can be avoided, the uniformity of emergent light near the hole position is improved, and bright spots and light bands are reduced; compared with other solutions in the prior art, black nickel does not need to be used, the manufacturing cost is reduced, no special requirement for the assembling process exists, and the working efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of backlights for display panels, and particularly to a backlight structure that can reduce light emission around the camera hole, thereby improving the uniformity of the emitted light. Background Art

[0002] In the existing market, in order to enhance the user experience, the mobile phone bezel is miniaturized, the size is gradually reduced, and the panel brightness is gradually increased. The surface form of mobile phones also presents diversification, including blind hole screens, water drop screens, full screens, curved screens, foldable screens, etc. Among them, the blind hole screen in LCD mobile phones is the current mainstream mobile phone and is more popular among consumers. However, the blind hole screen requires backlight drilling, which will cause light emission at the hole position and affect the display effect of the mobile phone.

[0003] Specifically, referring to Figure 1 and Figure 2 , respectively show a three-dimensional view and an enlarged view of a prism film of an LCD blind hole screen. In this prism film, there is a circular mounting hole at the upper position for placing the camera. Further, referring to Figure 3 , shows a cross-sectional view of an optional embodiment of this prism film applied in an LCD backlight structure. The backlight structure includes a hole fixing device 7 and an optical module. The optical module sequentially includes a reflective sheet 6 at the bottom, a light guide plate 5 above the reflective sheet 6, a diffusion film 4, and a prism film group from the bottom light source to the backlight emission direction. The prism film group includes an upper prism film 2 and a lower prism film 3. The lower prism film 3 is located between the upper prism film 2 and the diffusion film 4. The prism structure in the prism film group is on the side facing the user, that is, the backlight emission direction side. The upper prism film 2 includes a substrate and a prism structure. Exemplarily, the substrate can be a PET substrate, and the prism structure can be made of UV glue. The optical module has a circular mounting hole, and the hole fixing device 7 is placed in the mounting hole to fix the optical module and facilitate the placement and installation of the camera in the subsequent process. Generally, the hole fixing device 7 can be an iron frame.

[0004] Referring to Figure 4 , shows the optical path diagram at the position of the mounting hole. This optical path diagram corresponds to one side of the cross-sectional view shown in Figure 3 . Those skilled in the art can know that the same optical path also exists in other cross-sections of this mounting hole. In this optical path diagram, since there is a mounting hole in the middle of the light guide plate 5, the light in the light guide plate 5 can be emitted. After the emitted light is reflected by the hole fixing device 7, part of the reflected light enters the upper prism film 2 through the side wall of the upper prism film 2. Although there is a light-shielding tape 1 around the hole of the optical module, part of the reflected light will still be emitted along the direction perpendicular to the prism angle of the upper prism film, resulting in obvious light bands or uneven bright spots at the blind hole position of the screen, affecting the display quality near the blind hole.

[0005] See Figure 5 、 Figure 6 which shows a solution to this problem in the prior art. Black nickel 7-2 is plated on the side wall of the iron hole fixing device 7-1 facing the optical module to effectively reduce the light reflection in the mounting hole, reduce the light entering the upper prism film, and thus improve the light emission at the backlight hole position. However, this solution will increase the cost.

[0006] In another solution to this problem in the prior art, the prism film at the hole position is turned downward, that is, it is moved downward by 0.05 mm in the direction of the light guide plate, and the position of the diffusion film is moved upward by 0.05 mm in the backlight emission direction. However, this solution has high requirements for the assembly process. Due to certain tolerances in the assembly, the dimension of the misaligned position during assembly cannot be absolutely fixed to a certain point, resulting in a small adjustable space for assembly and it is difficult to ensure the overall effect.

[0007] Therefore, how to effectively solve the problem of light emission at the hole position, without increasing the cost, and reducing the requirements for the assembly process has become a technical problem that needs to be solved urgently in the prior art. Summary of the Invention

[0008] An embodiment of the present application provides a backlight structure and a liquid crystal module for reducing light emission at the hole position, which reduces the light incident surface between the inside of the prism film and the mounting hole for placing the camera device, thereby avoiding light emission at the hole position, improving the uniformity of the emitted light near the hole position, and reducing bright spots and light bands.

[0009] The present application discloses a backlight structure for reducing light emission at the hole position, including a hole fixing device and an optical module. The optical module includes a light guide plate, a diffusion film, and a prism film group arranged in sequence along the light emission direction;

[0010] The light guide plate is used to mix the light incident from the side and emit the mixed light to the diffusion film;

[0011] The diffusion film is used to diffuse the light incident from the light guide plate and emit the diffused light to the prism film group;

[0012] The prism film group is used to converge the incident light. The prism film group includes at least one prism film, and the prism film includes a substrate and a prism structure, and the prism structure is located on one side of the substrate in the light emission direction;

[0013] Wherein, the light guide plate and the diffusion film in the optical module are respectively provided with a first mounting hole and a second mounting hole, and the first mounting hole and the second mounting hole are provided with a hole fixing device for positioning and installing the camera module;

[0014] The prism film group does not have a prism structure at the orthographic projection position of the hole fixing device and has no lateral light incident surface, thereby reducing lateral light leakage.

[0015] In one embodiment, the prism film group has a third mounting hole, the hole fixing device extends into the third mounting hole, and a light-shielding layer is provided on the peripheral side wall of the third mounting hole of the prism film group.

[0016] In one embodiment, the prism film group includes an upper prism film and a lower prism film. Both the upper prism film and the lower prism film have the third mounting hole, and the light-shielding layer is provided on the peripheral side wall of the third mounting hole of the upper prism film.

[0017] In one embodiment, the light-shielding layer is coated black ink.

[0018] In one embodiment, on one side of the upper prism film along the light-emitting direction, a circle of light-shielding glue is covered from the hole fixing device to the peripheral edge of the third mounting hole.

[0019] In one embodiment, the prism film group does not have a mounting hole and a prism structure at the orthographic projection position of the hole fixing device.

[0020] In one embodiment, the prism film group includes an upper prism film and a lower prism film. Neither the upper prism film nor the lower prism film has a mounting hole and a prism structure at the orthographic projection position of the hole fixing device.

[0021] In one embodiment, on one side of the upper prism film along the light-emitting direction, a circle of light-shielding glue is provided from the orthographic projection position of the hole fixing device and its periphery.

[0022] In one embodiment, the optical module further includes a reflective sheet. The reflective sheet is disposed on the side of the light guide plate away from the light-emitting direction and is used to reflect the light incident from the light guide plate back to the light guide plate.

[0023] This application also discloses a liquid crystal display device, which includes the above-mentioned backlight structure.

[0024] The embodiments of this application adopt the above technical solutions to avoid light emission at the hole position, improve the uniformity of the light emitted near the hole position, and reduce bright spots and light bands.

[0025] Furthermore, this application does not need to use black nickel, which reduces the manufacturing cost, has no special requirements for the assembly and assembly process, and improves the work efficiency.

[0026] The above summary is for the purpose of the specification only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the present application will be readily apparent by reference to the drawings and the following detailed description. Description of the Drawings

[0027] In the drawings, unless otherwise specified, the same reference numerals throughout the several views refer to the same or similar components or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.

[0028] Figure 1 Shows an overall view of a prism film in the prior art;

[0029] Figure 2 Shows a partially enlarged view at the hole position of a prism film in the prior art;

[0030] Figure 3 Shows a cross-sectional view of a prism film applied in an LCD backlight structure in the prior art;

[0031] Figure 4 Shows an optical path diagram at the through-hole position of an LCD backlight structure in the prior art;

[0032] Figure 5 Shows a cross-sectional view at the mounting hole position of an LCD backlight structure using iron-nickel in the prior art;

[0033] Figure 6 Shows an optical path diagram at the mounting hole position of an LCD backlight structure using iron-nickel in the prior art;

[0034] Figure 7 Shows a perspective view of an upper prism film according to an embodiment of the present application;

[0035] Figure 8 Shows an optical path diagram at the mounting hole position of an LCD backlight structure according to an embodiment of the present application;

[0036] Figure 9 Shows a cross-sectional view at the mounting hole position of an LCD backlight structure according to another embodiment of the present application;

[0037] Figure 10 Shows an optical path diagram at the mounting hole position of an LCD backlight structure according to another embodiment of the present application.

[0038] Description of the Reference Numerals:

[0039] 1, 11, 21 are light-shielding tapes; 2, 12, 22 are upper prism films; 2-1, 12-1, 22-1 are prism structures; 2-2 is a substrate; 3, 13, 23 are lower prism films; 4, 14, 24 are diffusion films; 5, 15, 25 are light guide plates; 6, 16, 26 are reflector sheets; 7, 7-1, 17, 27 are hole fixing devices; 7-2 is black nickel; 18-1, 28-1 are first mounting holes; 18-2, 28-2 are second mounting holes; 18-3 is a third mounting hole. Detailed implementation manners

[0040] In the following, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present application. Therefore, the drawings and the description are considered to be exemplary in nature rather than restrictive.

[0041] The main idea of the present application is: in order to reduce the light emission at the hole position, the present application reduces or eliminates the light incident surface of the prism film on the display side of the backlight module at the hole position, so that the stray light at the hole position cannot enter the upper prism film, thereby reducing the light emission around the hole position; in addition, the prism film does not have a prism structure at the camera hole position, thereby avoiding the reduction of the camera FOV (Field of View) caused by the optical path change caused by the prism structure in the prism film.

[0042] A backlight structure for reducing light emission at the hole position, comprising a hole fixing device 17 and an optical module, the optical module comprising a reflector sheet 16, a light guide plate 15, a diffusion film 14 and a prism film group arranged in sequence along the light emitting direction;

[0043] The reflector sheet 16 is used to reflect the light incident from the light guide plate 15 back to the light guide plate 15;

[0044] The light guide plate 15 is used to mix the light incident from the side and emit the mixed light to the diffusion film 14;

[0045] The diffusion film 14 is used to diffuse the light incident from the light guide plate 15 and emit the diffused light to the prism film group;

[0046] The prism film group is used to converge the incident light, the prism film group includes at least one prism film, and the prism film includes a substrate and a prism structure 12-1, and the prism structure 12-1 is located on one side of the substrate in the light emitting direction;

[0047] Among them, the light guide plate 15 and the diffusion film 14 in the optical module are respectively provided with a first mounting hole 18-1 and a second mounting hole 18-2, and a hole fixing device 17 is arranged in the first mounting hole 18-1 and the second mounting hole 18-2. The hole fixing device 17 is used for positioning and installing the camera module;

[0048] In a specific example, the hole fixing device 17 can be an iron frame.

[0049] The prism film group does not have a prism structure at the orthographic projection position of the hole fixing device, and there is no lateral light incident surface, so as to reduce lateral light leakage. In particular, when the prism film group includes multiple prism films such as an upper prism film and a lower prism film, only the upper prism film needs to have no lateral light incident surface, so as to reduce lateral light leakage in the upper prism film.

[0050] Since there is no lateral light incident surface at the orthographic projection position of the hole fixing device 17, the light emitted from the light guide plate 15 cannot enter the prism film through the reflection of the hole fixing device, resulting in light emission that affects the display quality around the mounting hole, and ensuring the uniformity of the screen brightness. Not setting a prism structure at the orthographic projection position of the hole fixing device 17 is to prevent the light entering the camera from changing the light path due to the prism structure, thereby causing the field of view angle FOV of the camera to become smaller.

[0051] Embodiment 1

[0052] An implementation manner of the present application without a lateral light incident surface is that the prism film group has a third mounting hole 18-3, and the hole fixing device 17 extends into the third mounting hole 18-3, and a light shielding layer is arranged on the side wall around the third mounting hole of the prism film group.

[0053] In a specific embodiment, the light shielding layer is coated black ink.

[0054] See Figure 7 、 8 , which respectively show a perspective view of the upper prism film and an optical path diagram at the position of the mounting hole of the LCD backlight structure according to an embodiment of the present application.

[0055] The prism film group includes an upper prism film 12 and a lower prism film 13, and the lower prism film 13 is located between the upper prism film 12 and the diffusion film 14.

[0056] The upper prism film 12 and the lower prism film 13 are provided with a third mounting hole 18-3, the hole fixing device 17 extends into the third mounting hole 18-3, and a light shielding layer is arranged on the side wall around the third mounting hole 18-3 of the prism film group. Specifically, black ink is coated on the side wall around the mounting hole of the upper prism film 12.

[0057] Therefore, seeFigure 8 By coating black ink, the light emitted from the side of the first mounting hole 18-1 of the light guide plate 15 is scattered on the side wall of the third mounting hole 18-3 of the prism film group after passing through the hole fixing device 17 such as an iron frame. Since there is black ink on the side wall of the upper prism film hole position, the light reflected by the glue iron can be effectively reduced from entering the side wall of the upper prism, so that there is no lateral light incident surface at the orthographic projection position of the prism film group on the hole fixing device 17, thereby reducing side light leakage.

[0058] Since the upper prism film 12 and the lower prism film 13 are provided with the third mounting hole 18-3, there is no prism structure 12-1 at the position of the corresponding mounting hole of the upper and lower prism films, that is, at the orthographic projection position of the hole fixing device, thus avoiding the influence on the beam quality of the camera.

[0059] In this embodiment, a light-shielding layer is provided on the peripheral side wall of the third mounting hole 18-3 of the prism film group. When the prism film group includes an upper prism film and a lower prism film, only a light-shielding layer needs to be provided on the peripheral side wall of the third mounting hole 18-3 of the upper prism film 12, for example, by coating black ink, but a light-shielding layer can also be further provided on the peripheral side wall of the third mounting hole 18-3 of the lower prism 12, for example, by coating black ink, so as to improve the effect of eliminating incident light.

[0060] In this embodiment, the black ink can be coated by the following method: screen-print black oil on the side wall of the drilling tool. During the process of drilling the upper prism film, the black ink on the side wall of the tool will be transferred to the side wall of the upper prism film hole position, and at the same time, a circle of prisms near the upper prism film hole position will also be screen-printed with black ink.

[0061] Furthermore, in order to improve the light-shielding effect, on one side of the upper prism film 12 along the light-emitting direction, a circle of light-shielding glue is covered from the hole fixing device 17 to the peripheral edge of the third mounting hole 18-3, so as to further improve the light-shielding effect and reduce side light leakage, that is, the incident light entering the prism film.

[0062] Embodiment 2

[0063] Another implementation manner of the present application without a lateral light incident surface is that only other components in the optical module except the prism film group have mounting holes, and the prism film group does not have mounting holes and prism structures at the orthographic projection position of the hole fixing device.

[0064] See Figure 9 、 10 , which respectively show a cross-sectional view and a light path diagram at the mounting hole position of the LCD backlight structure according to another embodiment of the present application.

[0065] In this embodiment, the same technical features have the same meaning as those in the previous embodiment.

[0066] The backlight structure includes a hole fixing device 27 and an optical module. The optical module sequentially has a reflective sheet 26, a light guide plate 25, a diffusion film 24, and a prism film group from the bottom to the light-emitting side of the backlight.

[0067] The reflective sheet 26 is used to reflect the light incident from the light guide plate 25 back to the light guide plate 15.

[0068] The light guide plate 25 is used to mix the light incident from the side and emit the mixed light to the diffusion film 24.

[0069] The diffusion film 24 is used to diffuse the light incident from the light guide plate 25 and emit the diffused light to the prism film group.

[0070] The prism film group is used to converge the incident light. The prism film group includes at least one prism film. The prism film includes a substrate and a prism structure 22-1. The prism structure 22-1 is located on one side of the substrate in the light-emitting direction.

[0071] Wherein, the light guide plate 25 and the diffusion film 24 in the optical module are respectively provided with a first mounting hole 28-1 and a second mounting hole 28-2. The first mounting hole 28-1 and the second mounting hole 28-2 are provided with the hole fixing device 27. The hole fixing device 27 is used to position and install the camera module.

[0072] In a specific example, the hole fixing device 27 can be an iron frame.

[0073] No mounting holes and prism structures are provided at the orthographic projection position of the prism film group on the hole fixing device 27.

[0074] Specifically, the prism film group includes an upper prism film 22 and a lower prism film 23. Neither the upper prism film 22 nor the lower prism film 23 has mounting holes and prism structures at the orthographic projection position of the hole fixing device 27, and prism structures are reserved at other positions.

[0075] Therefore, since the prism film group does not have mounting holes at the orthographic projection position of the hole fixing device, and thus does not include a side light-incident surface, the light emitted from the light guide plate cannot enter the prism film through the reflection of the hole fixing device, thereby reducing side leakage light. No prism structure is provided at the orthographic projection position of the prism film group on the hole fixing device, avoiding the reduction of the camera field of view FOV.

[0076] See Figure 9 、 10 , on one side of the upper prism film 22 along the light-emitting direction, a light-shielding adhesive 21 is provided in a circle from the orthographic projection position of the hole fixing device 27 and its periphery, thereby further improving the light-shielding effect.

[0077] In this embodiment, it can be prepared by the following method: when preparing the prism structure by coating UV glue on the PET substrate part of the prism film, use a roller die to roll and flatten the UV glue at the hole positions, so as to remove the prism structure at the hole positions, and retain the prism structure at other positions.

[0078] Another preparation method is: apply a release layer with a thickness of 1 - 2 um at the position of the mounting hole corresponding to the PET substrate of the prism film to reduce the adhesion between the glue and the PET, ensuring that the coated glue cannot spread at the hole positions, thereby removing the prism structure at these hole positions.

[0079] In this embodiment, after the light emitted by the LED in the backlight module exits from the light guide plate, although it may be reflected by the hole fixing device, since there are no mounting holes in the upper and lower prism films, there is no lateral light incident surface. The light is reflected and refracted by the PET substrates at the bottoms of the upper and lower prism films, reducing the light emitted along the prism structure of the upper prism film.

[0080] This application further discloses a liquid crystal display device, which includes the backlight structure of the above embodiment.

[0081] Those skilled in the art should understand that in this application, neither the reflective sheet nor the lower prism film is necessary. The prism film group can also include more than two prism films. As long as the prism film on the light - emitting side in the prism film group has no lateral light incident surface at the orthographic projection position of the hole fixing device to reduce the light scattering around the hole, and the prism film group does not have a prism structure at the camera hole position, it can avoid the optical path change caused by the prism structure.

[0082] Therefore, the two implementation manners of this application do not provide a prism structure at the orthographic projection position of the hole fixing device, have no lateral light incident surface, and have the following advantages:

[0083] (1) Since the prism film has no lateral light incident surface, it can avoid the light emission at the camera mounting hole position, improve the uniformity of the emitted light near the hole position, and reduce bright spots and light bands.

[0084] (2) Compared with other solutions in the prior art, this application does not need to use black nickel, which reduces the manufacturing cost, has no special requirements for the assembly process, and improves the work efficiency.

[0085] Other compositions of the peeling - off prevention pattern of the above embodiment can adopt various technical solutions known to those of ordinary skill in the art now and in the future, which will not be described in detail here.

[0086] In the description of this specification, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0087] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0088] In the present application, unless otherwise clearly specified and defined, the terms "mounted", "connected", "coupled", "fixed", etc. shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral body; it may be a mechanical connection, an electrical connection, or a communication connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal connection or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0089] In the present application, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the first feature is at a higher horizontal level than the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the first feature is at a lower horizontal level than the second feature.

[0090] It should be noted that although the steps of the method in the present application are described in a specific order in the accompanying drawings, this does not require or imply that these steps must be executed in that specific order, or that all the steps shown must be executed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step for execution, and / or one step may be decomposed into multiple steps for execution, etc. The above-mentioned accompanying drawings are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present application, rather than for the purpose of limitation. It is easy to understand that the processes shown in the above-mentioned accompanying drawings do not indicate or limit the chronological order of these processes. Additionally, it is also easy to understand that these processes may be executed synchronously or asynchronously, for example, in multiple modules.

[0091] The foregoing disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, the components and settings of specific examples are described above. Of course, they are only examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplicity and clarity, and in itself does not indicate the relationship between the various embodiments and / or settings discussed.

[0092] As described above, the above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of various changes or substitutions, and these should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A backlight structure for reducing light emission at the hole position, characterized in that: It includes a hole fixing device and an optical module. The optical module includes a light guide plate, a diffusion film, and a prism film group arranged in sequence along the light-emitting direction; The light guide plate is used to mix the light incident from the side and emit the mixed light to the diffusion film; The diffusion film is used to diffuse the light incident from the light guide plate and emit the diffused light to the prism film group; The prism film group is used to converge the incident light. The prism film group includes at least one prism film, and the prism film includes a substrate and a prism structure, and the prism structure is located on one side of the substrate in the light-emitting direction; Wherein, the light guide plate and the diffusion film in the optical module are respectively provided with a first mounting hole and a second mounting hole, and the first mounting hole and the second mounting hole are provided with a hole fixing device, and the hole fixing device is used to position and install the camera module; The prism film group does not have a prism structure at the orthographic projection position of the hole fixing device and has no lateral light incident surface, so as to reduce lateral light leakage.

2. The backlight structure according to claim 1, characterized in that: The prism film group has a third mounting hole, the hole fixing device extends into the third mounting hole, and a light-shielding layer is provided on the peripheral side wall of the third mounting hole of the prism film group.

3. The backlight structure according to claim 2, characterized in that: The prism film group includes an upper prism film and a lower prism film. Both the upper prism film and the lower prism film have the third mounting hole, and the light-shielding layer is provided on the peripheral side wall of the third mounting hole of the upper prism film.

4. The backlight structure according to claim 2 or 3, characterized in that: The light-shielding layer is a coated black ink.

5. The backlight structure according to claim 3, characterized in that: On one side of the upper prism film along the light-emitting direction, a circle of light-shielding glue is covered from the hole fixing device to the peripheral edge of the third mounting hole.

6. The backlight structure according to claim 1, characterized in that: The prism film group does not have a mounting hole and a prism structure at the orthographic projection position of the hole fixing device.

7. The backlight structure according to claim 6, characterized in that: The prism film group includes an upper prism film and a lower prism film. Neither the upper prism film nor the lower prism film has a mounting hole and a prism structure at the orthographic projection position of the hole fixing device.

8. The backlight structure according to claim 7, characterized in that: On one side of the upper prism film along the light-emitting direction, a circle of light-shielding glue is provided from the orthographic projection position of the hole fixing device and its periphery.

9. The backlight structure according to any one of claims 2-8, characterized in that: The optical module further includes a reflector, and the reflector is arranged on the side of the light guide plate away from the light-emitting direction, and is used to reflect the light incident from the light guide plate back to the light guide plate.

10. A liquid crystal display device, characterized in that: The liquid crystal display device includes the backlight structure according to any one of claims 1-9.

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