Backlight module and display device

Abstract

The application provides a backlight module and a display device. The backlight module comprises a back plate, the back plate comprising a bottom wall and a side wall, the side wall being connected with the bottom wall, the inner surface of the side wall having a first accommodating groove; a diffusion plate, the edge of the diffusion plate being arranged in the first accommodating groove, the diffusion plate, the side wall and the bottom wall forming a first light mixing cavity; a fixing frame, the fixing frame being connected with the back plate; a diaphragm assembly, the diaphragm assembly being connected with the fixing frame, the diaphragm assembly being arranged in a spaced manner with the diffusion plate to form a second light mixing cavity. The backlight module can improve the uniformity of light emission.

Description

Technical Field

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

[0002] In display devices, the backlight module, as one of the core components of an LCD TV, plays a vital role in providing illumination to the LCD panel, ensuring that images and text are displayed clearly.

[0003] In existing technologies, to improve image display quality, optical diffusion elements, such as diffuser plates and film assemblies, are typically placed on the light-emitting side of the backlight module to allow light to be diffused and projected onto the liquid crystal layer more uniformly. However, this structure has certain drawbacks: after passing through the diffuser plate and before reaching the film assembly, light is prone to interference due to light path crossing. This interference may affect the final display effect, such as causing smudges or uneven brightness. Utility Model Content

[0004] This application provides a backlight module and a display device that can improve the uniformity of light output.

[0005] This application provides a backlight module, including: A back panel, the back panel including a bottom wall and a side wall, the side wall being connected to the bottom wall, and the inner surface of the side wall having a first receiving groove; A diffuser plate, the edge of which is disposed within the first receiving groove, the diffuser plate being spaced apart from the bottom wall, and the diffuser plate, the side wall, and the bottom wall forming a first light mixing cavity; A fixing frame is disposed on the side of the back plate near the light-emitting surface of the diffuser plate, and the fixing frame is connected to the back plate; A diaphragm assembly connected to the fixture, the diaphragm assembly being spaced apart from the diffuser plate to form a second mixing cavity.

[0006] In some embodiments, the sidewall includes a first connecting portion and a second connecting portion, the first connecting portion being connected to the bottom wall, the second connecting portion being connected to the side of the first connecting portion away from the bottom wall, the second connecting portion protruding from the outer surface of the first connecting portion, and the inner surface of the second connecting portion being recessed to form the first receiving groove.

[0007] In some embodiments, the second connecting portion includes a first limiting wall, a second limiting wall, and a third limiting wall. The first limiting wall is connected to the first connecting portion. The second limiting wall is connected to the end of the first limiting wall away from the first connecting portion. The third limiting wall is connected to the end of the second limiting wall away from the first limiting wall. The first limiting wall and the third limiting wall are opposite to each other and spaced apart, and together with the second limiting wall, they form the first receiving groove. The edge of the diffuser plate is inserted between the first limiting wall and the third limiting wall.

[0008] In some embodiments, the inner surface of the fixture has a second receiving groove, and the edge of the diaphragm assembly is disposed within the second receiving groove.

[0009] In some embodiments, the inner surface of the fixing frame is further provided with a reflective slope, the reflective slope being connected to the groove wall of the second receiving groove and extending from the groove opening of the second receiving groove toward the diffuser plate, the reflective slope being toward the diaphragm assembly.

[0010] In some embodiments, the fixing frame includes a support and a baffle, the support being connected to the baffle to enclose and form the second receiving groove.

[0011] In some embodiments, the mounting bracket is disposed outside the first receiving groove and fixed to the back plate along the thickness direction of the backlight module.

[0012] In some embodiments, the support portion extends at least partially into the first receiving groove, the support portion abuts against the diffuser plate, and the baffle is detachably connected to the back plate.

[0013] In some embodiments, the back plate has a protrusion on its side wall, the protrusion being located on the periphery of the light-emitting side of the diffuser plate; the baffle has a limiting groove, the protrusion being engaged in the limiting groove.

[0014] This application embodiment also provides a display device, the display device comprising: Backlight module, wherein the backlight module is the aforementioned backlight module; A liquid crystal module is disposed on the light-emitting side of the backlight module, and the edge of the liquid crystal module is fixed to the mounting bracket of the backlight module.

[0015] The backlight module and display device provided in this application embodiment have a first mixing cavity and a second mixing cavity. After the light is initially homogenized by the first mixing cavity, it enters the second mixing cavity and continues to undergo homogenization processes such as reflection, refraction, and scattering within the second mixing cavity. Under the action of the second mixing cavity, the uniformity of the light is further improved. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a first structure of a backlight module provided in an embodiment of this application.

[0018] Figure 2 This is a schematic diagram of a second structure of the backlight module provided in an embodiment of this application.

[0019] Figure 3 This is a schematic diagram of the structure of the backplate provided in an embodiment of this application.

[0020] Figure 4 This is a schematic diagram of a first structure of the fixing frame provided in an embodiment of this application.

[0021] Figure 5 This is a schematic diagram of a second structure of the fixing frame provided in an embodiment of this application.

[0022] Figure 6 for Figure 1 A magnified view of part A.

[0023] Figure 7 for Figure 2 A magnified view of part B. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0025] This application provides a backlight module and a display device that can improve the uniformity of light emission. The following is a detailed description with reference to the accompanying drawings.

[0026] Please see Figure 1 as well as Figure 2 , Figure 1 This is a schematic diagram of a first structure of a backlight module provided in an embodiment of this application. Figure 2 This is a schematic diagram of a second structure of the backlight module provided in an embodiment of this application.

[0027] This application provides a backlight module 100, whose main function is to provide a uniform background light source for the liquid crystal panel, enabling the liquid crystal panel to display images normally. The backlight module 100 is typically composed of multiple optical elements and structural components, and requires reasonable optical and structural design to achieve effective control and utilization of light in order to improve display effects, such as brightness uniformity and contrast.

[0028] The backlight module 100 includes a backplate 10, a diffuser plate 20, a mounting bracket 40, and a diaphragm assembly 50.

[0029] The backplate 10 serves to support and protect the internal components of the backlight module 100, providing a mounting base for other components such as the diffuser plate 20 and the mounting bracket 40. It also helps to prevent external factors from interfering with or damaging the internal components of the backlight module 100. The backplate 10 includes a bottom wall 11 and a side wall 12, which is connected to the bottom wall 11 and extends from the edge of the bottom wall 11 by bending.

[0030] The inner surface of the sidewall 12 has a first receiving groove 121, which can effectively limit the diffuser plate 20 and prevent it from shaking or falling off during use. In terms of optical performance, the space reserved in the first receiving groove 121 can accommodate the expansion and contraction of the diffuser plate 20 due to temperature changes.

[0031] The diffuser plate 20 is an optical material capable of diffusing light. When light passes through the diffuser plate 20, the particles or structures inside the diffuser plate 20 scatter the light, thereby converting the light emitted by a point light source or line light source into a uniform surface light source, improving the uniformity of light distribution in the display area, reducing the appearance of bright spots and dark areas, and improving display quality. The edge of the diffuser plate 20 is disposed within the first receiving groove 121, and the diffuser plate 20 is spaced apart from the bottom wall 11. The diffuser plate 20, the side wall 12, and the bottom wall 11 together form a first light mixing cavity 30.

[0032] The backlight module 100 also includes a light strip 60 disposed on the bottom wall 11 of the back panel 10. The light strip 60 includes a circuit board 61 and a light-emitting unit 62 disposed on the circuit board 61 to form a point light source. The backlight module 100 also includes a reflector 70 disposed on the side wall 12 of the back panel 10 for reflecting light.

[0033] When the light emitted by the light source enters the first mixing cavity 30, it undergoes multiple reflections on the bottom wall 11 and side wall 12. Subsequently, the presence of the diffuser plate 20 causes these reflected rays to be scattered as they pass through the diffuser plate 20, transforming the light emitted by the point light source or line light source into a uniform surface light source.

[0034] The mounting bracket 40 can also be called a frame. The mounting bracket 40 serves as a connecting element and can be used to fix structures such as the diaphragm assembly 50. The mounting bracket 40 is located on the side of the back plate 10 near the light-emitting surface of the diffuser plate 20, and the mounting bracket 40 is connected to the back plate 10.

[0035] The diaphragm assembly 50 is connected to the mounting bracket 40, and is spaced apart from the diffuser plate 20 to form a second mixing cavity 80. The diaphragm assembly 50 typically consists of multiple diaphragms with different functions, each possessing unique optical properties. For example, a brightness enhancement film, through a special microstructure design, can reflect and refract light, allowing more light to propagate towards the display direction, thereby improving light utilization and display brightness. A polarizer can control the polarization direction of light, allowing only light with a specific polarization direction to pass through, reducing interference from reflected light and improving display contrast and color saturation.

[0036] After the light that has been initially mixed by the first mixing cavity 30 and the diffuser plate 20 is adjusted and optimized, it can undergo sufficient secondary reflection and diffusion in the second mixing cavity 80 before reaching the diaphragm assembly 50, effectively eliminating interference between light rays at different angles, thereby further improving the uniformity of the light output surface.

[0037] Please see Figure 3 , Figure 3 This is a schematic diagram of the structure of the back panel provided in an embodiment of this application. The side wall 12 includes a first connecting portion 122 and a second connecting portion 123. The first connecting portion 122 is connected to the bottom wall 11 to form a first light mixing cavity 30, which is used to perform preliminary mixing and diffusion of the light emitted by the light source, thereby improving the uniformity of light output.

[0038] The second connecting part 123 is connected to the side of the first connecting part 122 away from the bottom wall 11. The second connecting part 123 protrudes from the outer surface of the first connecting part 122. This structural design helps to enhance the overall rigidity and structural stability of the side wall 12, while providing a reliable installation base for the diffuser plate 20.

[0039] The inner surface of the second connecting part 123 is recessed to form a first receiving groove 121, which is used to receive and position the edge of the diffuser plate 20.

[0040] The second connecting portion 123 includes a first limiting wall 1231, a second limiting wall 1232, and a third limiting wall 1233. The first limiting wall 1231 is connected to the first connecting portion 122, the second limiting wall 1232 is connected to the end of the first limiting wall 1231 away from the first connecting portion 122, and the third limiting wall 1233 is connected to the end of the second limiting wall 1232 away from the first limiting wall 1231. The first limiting wall 1231 and the third limiting wall 1233 are positioned opposite each other and spaced apart, forming a first receiving groove 121 together with the second limiting wall 1232. This first receiving groove 121 effectively restricts the displacement of the diffuser plate 20 in the lateral and longitudinal directions, preventing it from shifting or loosening during vibration or assembly, thereby ensuring the relative positional accuracy and optical performance consistency of the optical components. The edge of the diffuser plate 20 is inserted between the first limiting wall 1231 and the third limiting wall 1233, and achieves stable support through contact with the second limiting wall 1232. The edge of the diffuser plate 20 is inserted between the first limiting wall 1231 and the third limiting wall 1233, and achieves stable support through contact with the first limiting wall 1231.

[0041] The first connecting part 122 and the second connecting part 123 can be integrally formed. For example, they can be integrally processed by stamping, die casting or injection molding. This integral structure avoids the cumulative errors caused by assembling multiple parts, improves the mechanical strength and dimensional accuracy of the overall structure, and reduces production complexity and assembly costs, which is conducive to large-scale manufacturing.

[0042] Please see Figure 4 as well as Figure 5 , Figure 4 This is a schematic diagram of a first structure of the fixing frame provided in an embodiment of this application. Figure 5 This is a schematic diagram of a second structure of the fixing frame provided in an embodiment of this application.

[0043] The inner surface of the mounting bracket 40 has a second receiving groove 41, and the edge of the diaphragm assembly 50 is disposed within the second receiving groove 41. The second receiving groove 41 can effectively limit the diaphragm assembly 50, effectively preventing the diaphragm assembly 50 from shifting position, loosening, or even falling out during module vibration, handling, or long-term use, thereby ensuring the stability and reliability of the optical system stack. In terms of optical performance, the second receiving groove 41 provides necessary expansion and contraction space for the diaphragm assembly 50 under temperature change conditions.

[0044] The inner surface of the fixing frame 40 is also provided with a reflective inclined surface 42, which is disposed between the diffuser plate 20 and the diaphragm assembly 50. The reflective inclined surface 42 is connected to the groove wall of the second receiving groove 41 and extends from the groove opening of the second receiving groove 41 toward the diffuser plate 20.

[0045] The reflective bevel 42 can redirect and reflect light that was originally intended to escape or leak from the edge of the diffuser 20 into the non-display area, as well as light that would illuminate the vicinity of the second receiving groove 41, back to the edge area of ​​the diaphragm assembly 50 and even the entire effective display area. This optical compensation mechanism significantly enhances the brightness output of the surrounding area of ​​the backlight module 100, effectively improving the dark edges and dark corners caused by insufficient edge light, thereby comprehensively improving the overall brightness uniformity and visual quality of the display screen.

[0046] The reflective capability of the reflective slope 42 can be achieved in two ways. One way is to use white plastic as the material for the mounting bracket 40, as white plastic itself has a certain reflective function. The surface of the white plastic can reflect most of the incident light, reflecting the light emitted from the diffuser plate 20 that might otherwise be scattered in other directions back to the edge of the diaphragm assembly 50. The other way is to form the reflective slope 42 by setting a reflective layer on the slope of the inner surface of the mounting bracket 40. The reflective layer can be made of a high-reflectivity metal material to form a metal reflective layer, such as aluminum or silver, which is uniformly deposited on the slope through processes such as evaporation or sputtering. The metal reflective layer has extremely high reflectivity, capable of reflecting almost all of the incident light.

[0047] The mounting bracket 40 includes a support portion 43 and a baffle 44. The support portion 43 and the baffle 44 are connected to form a second receiving groove 41 for securely accommodating the edge of the diaphragm assembly 50. This integrated groove structure not only provides accurate installation positioning for the diaphragm assembly but also structurally enhances the overall rigidity of the mounting bracket 40. The reflective ramp 42 is located on the support portion 43.

[0048] Please see Figure 1 as well as Figure 6 , Figure 6 for Figure 1 A magnified view of part A. In one case, the mounting bracket 40 is disposed outside the first receiving groove 121 and fixed to the back plate 10 along the thickness direction of the backlight module 100. This layout facilitates the thinning and compactness of the backlight module 100, while avoiding interference with the light propagation within the first light mixing cavity 30, thus ensuring high light efficiency.

[0049] Please see Figure 2 as well as Figure 7 , Figure 7 for Figure 2A magnified view of part B. In another case, the support portion 43 extends at least partially into the first receiving groove 121. The support portion 43 is disposed on the light-emitting side of the diffuser plate 20, which not only provides auxiliary support for the diffuser plate 20, but also effectively solves the light leakage problem caused by the diffuser plate 20 jumping out, helps to reduce the thickness of the whole machine, and can also prevent it from deforming due to its own weight or external force, and improves the stability of the entire optical architecture, thereby helping to maintain the consistency of the light mixing distance and the uniformity of light output. In this case, the support portion 43 can abut against the diffuser plate 20.

[0050] The baffle 44 is detachably connected to the back plate 10, facilitating subsequent maintenance and component replacement. Specifically, the back plate 10 has a protrusion 124 on its side wall 12, located on the outer periphery of the light-emitting side of the diffuser plate 20; correspondingly, the baffle 44 has a limiting groove 441, in which the protrusion 124 engages. This engaging structure enables quick assembly and reliable fixation between the mounting bracket 40 and the back plate 10.

[0051] The protrusion 124 can be the third limiting wall 1233 in the above embodiment. By reusing the function of the back plate 10 structure, the positioning and installation of the fixing frame 40 are achieved without adding extra parts, demonstrating the integration of the structural design. When the baffle 44 is engaged with the back plate 10, the support part 43 and the first limiting wall 1231 are respectively set on both sides of the diffuser plate 20, so that the support part 43 can limit the diffuser plate 20, effectively solving the light leakage problem caused by the diffuser plate 20 jumping out; and the reflective slope 42 on the support part 43, as described above, can effectively improve the edge brightness.

[0052] This application provides a display device, which is an electronic device or component whose core function is to convert electronic signals, digital signals, or other forms of signals into visual information such as images, text, and numbers that can be recognized by the human eye. This display device can be a television, computer monitor, mobile phone screen, vehicle display screen, etc.

[0053] The display device includes a backlight module 100 and a liquid crystal module. The backlight module 100 is the same as the one described in the above embodiment. The liquid crystal module is disposed on the light-emitting side of the backlight module 100, providing more uniform and higher brightness light emission, significantly improving the brightness uniformity and average brightness of the display device, and bringing users a clearer, more realistic, and brighter visual experience.

[0054] The edge of the liquid crystal module is fixed to the mounting bracket 40 of the backlight module 100 and is attached to the mounting bracket 40 to be positioned on the light-emitting side of the film assembly 50.

[0055] To further improve the stability and reliability of the overlap, a stress dispersion and buffer structure is set at the overlap between the LCD module and the mounting bracket 40. Elastic materials such as rubber pads or silicone pads can be added to the overlap area. When the LCD module is subjected to external force, the elastic material can deform to absorb and disperse stress, reduce the concentrated effect of stress on the LCD module, and thus protect the LCD module from damage.

[0056] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0057] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features.

[0058] The backlight module and display device provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application, and the descriptions of the embodiments above are only for the purpose of helping to understand this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A backlight module, characterized in that, include: A back panel, the back panel including a bottom wall and a side wall, the side wall being connected to the bottom wall, and the inner surface of the side wall having a first receiving groove; A diffuser plate, the edge of which is disposed within the first receiving groove, the diffuser plate being spaced apart from the bottom wall, and the diffuser plate, the side wall, and the bottom wall forming a first light mixing cavity; A fixing frame is disposed on the side of the back plate near the light-emitting surface of the diffuser plate, and the fixing frame is connected to the back plate; A diaphragm assembly connected to the fixture, the diaphragm assembly being spaced apart from the diffuser plate to form a second mixing cavity.

2. The backlight module according to claim 1, characterized in that, The sidewall includes a first connecting portion and a second connecting portion. The first connecting portion is connected to the bottom wall, and the second connecting portion is connected to the side of the first connecting portion away from the bottom wall. The second connecting portion protrudes from the outer surface of the first connecting portion, and the inner surface of the second connecting portion is recessed to form the first receiving groove.

3. The backlight module according to claim 2, characterized in that, The second connecting portion includes a first limiting wall, a second limiting wall, and a third limiting wall. The first limiting wall is connected to the first connecting portion. The second limiting wall is connected to the end of the first limiting wall away from the first connecting portion. The third limiting wall is connected to the end of the second limiting wall away from the first limiting wall. The first limiting wall and the third limiting wall are opposite to each other and spaced apart, and together with the second limiting wall, they form the first receiving groove. The edge of the diffuser plate is inserted between the first limiting wall and the third limiting wall.

4. The backlight module according to any one of claims 1 to 3, characterized in that, The inner surface of the fixture has a second receiving groove, and the edge of the diaphragm assembly is disposed within the second receiving groove.

5. The backlight module according to claim 4, characterized in that, The inner surface of the fixing frame is also provided with a reflective slope, which is connected to the groove wall of the second receiving groove and extends from the groove opening of the second receiving groove toward the diffuser plate, with the reflective slope facing the diaphragm assembly.

6. The backlight module according to claim 4, characterized in that, The fixing frame includes a support and a baffle, the support being connected to the baffle to form the second receiving groove.

7. The backlight module according to claim 6, characterized in that, The fixing bracket is disposed outside the first receiving groove and fixed to the back plate along the thickness direction of the backlight module.

8. The backlight module according to claim 6, characterized in that, The support portion extends at least partially into the first receiving groove, the support portion is disposed on the light-emitting side of the diffuser plate, and the baffle is detachably connected to the back plate.

9. The backlight module according to claim 8, characterized in that, The back plate has a protrusion on its side wall, which is located on the periphery of the light-emitting side of the diffuser plate; the baffle has a limiting groove, and the protrusion is engaged in the limiting groove.

10. A display device, characterized in that, include: A backlight module, wherein the backlight module is the backlight module according to any one of claims 1 to 9; A liquid crystal module is disposed on the light-emitting side of the backlight module, and the edge of the liquid crystal module is fixed to the mounting bracket of the backlight module.

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