Backlight module and display terminal

Abstract

The invention relates to a backlight module and a display terminal. The backlight module comprises a back plate, a light guide plate and an optical film, the light guide plate and the optical film are located in the back plate, the light guide plate comprises a light guide body part and a limiting part, a limiting groove is formed in the edge of the optical film, the inner wall of the limiting groove is arranged around the limiting part, and an avoiding groove corresponding to the limiting part is further formed in the side plate. At least part of the limiting part is located between the light guide body part and the receding groove. According to the backlight module, the avoiding groove is formed in the side plate, and the limiting part in the light guide plate extends towards the avoiding groove, so that the distance between the edge of the optical film and the window area is increased, part of light is prevented from being guided out from the edge of the optical film, and the technical problem that light leakage occurs to the backlight module is solved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a backlight module and a display terminal. Background Art

[0002] The liquid crystal display module includes a display panel and a backlight module. The backlight module includes a backplane and multiple optical films fixed in the backplane. Currently, in order to improve the mechanical vibration tolerance of liquid crystal display modules in harsh environments and adapt to application scenarios such as automotive, the mechanical vibration standards of liquid crystal display modules are becoming increasingly stringent. To meet this requirement, the optical film is usually provided with a hanging ear, which cooperates with the limiting column on the backlight module to limit the optical film. However, due to the small distance between the existing hanging ear and the window area of ​​the backlight module, some light is guided out from the edge of the optical film, causing the backlight module to leak technical problems. Summary of the Invention

[0003] The embodiments of the present application provide a backlight module and a display terminal to improve the technical problem of light leakage in the backlight module.

[0004] In a first aspect, a backlight module according to the present application includes:

[0005] A back plate, comprising a bottom plate and side plates arranged on the periphery of the bottom plate, wherein the bottom plate and the side plates form a receiving cavity;

[0006] a light guide plate comprising a light guide body and a limiting portion connected to the light guide body, wherein the light guide body is located in the accommodating cavity and is spaced apart from the side plate;

[0007] At least one optical film is disposed on a side of the light guide body away from the bottom plate, wherein a limiting groove is defined at an edge of the optical film, and an inner wall of the limiting groove is disposed around the limiting portion;

[0008] Among them, the multiple side panels include a first side panel arranged adjacent to the limiting portion, and the first side panel is also provided with an avoidance groove corresponding to the limiting portion, and at least part of the limiting portion is located between the light guide body and the avoidance groove.

[0009] Optionally, the first side panel includes a first sub-panel and a second sub-panel arranged along an extension direction of the first side panel, and in a thickness direction of the light guide plate, a height of the first sub-panel is smaller than a height of the second sub-panel;

[0010] The avoidance groove is provided on the first sub-board, and the avoidance groove separates the first sub-board into a first sub-portion and a second sub-portion which are spaced apart from each other, and the second sub-portion is connected to the second sub-board.

[0011] Optionally, the plurality of side panels further include a second side panel disposed adjacent to the first side panel, and the first sub-portion and the second side panel have an overlapping portion in an extending direction of the second side panel;

[0012] The optical film includes a first hanging ear located on one side of the limiting portion, the first hanging ear extends toward the area where the first sub-portion and the second side panel are located, and the end surface of the first hanging ear close to the first sub-portion extends at least to between the first sub-portion and the light guide body; or / and,

[0013] The optical film includes a second hanging ear located on the other side of the limiting portion, the second hanging ear extends toward the second sub-portion, and the end surface of the second hanging ear close to the second sub-portion extends at least to between the second sub-portion and the light guide body portion.

[0014] Optionally, a length of the first hanging ear in the extension direction of the first side plate is greater than or equal to 2.25 mm.

[0015] Optionally, a length of the second hanging ear in the extension direction of the first side plate is greater than or equal to 2.25 mm.

[0016] Optionally, an overlapping width of the first hanging ear and / or the second hanging ear and the limiting portion in the extension direction of the second side plate is greater than or equal to 2 mm.

[0017] Optionally, the backlight module further comprises a light bar disposed between the light guide plate and the second side plate, wherein the light bar comprises a base and a plurality of light-emitting units disposed on the base;

[0018] Wherein, protrusions extending toward the light bar are provided at both ends of the light guide main body, and the protrusions and the base are spaced apart.

[0019] Optionally, a buffer pad is provided on a surface of the base facing the light guide main body, and the buffer pad is in contact with the protrusion.

[0020] Optionally, in the extension direction of the first side panel, the second hanging ear and the second sub-board are spaced apart, and the first hanging ear and the light bar are spaced apart.

[0021] Optionally, a distance between a side surface of the optical film close to the light bar and the light bar is greater than a distance between the light guide body and the light bar.

[0022] Optionally, the backlight module includes a plurality of stacked optical films, the area of ​​the first hanging ear in the optical film away from the light guide plate is larger than the area of ​​the first hanging ear in the optical film close to the light guide plate, or / and the area of ​​the second hanging ear in the optical film away from the light guide plate is larger than the area of ​​the second hanging ear in the optical film close to the light guide plate.

[0023] Optionally, the optical film is provided with a avoidance opening on the side close to the light bar, the limiting groove is provided with a first arc on the side close to the avoidance opening, and the avoidance opening is provided with a second arc on the side close to the limiting groove, and the ratio of the size of the line connecting the first center of the first arc and the second center of the second arc on the first hanging ear to the length of the first hanging ear in the extension direction of the first side panel is greater than or equal to 1.2.

[0024] Optionally, the backlight module includes a plurality of stacked optical films, and the thickness of the optical film away from the light guide plate is greater than the thickness of the optical film close to the light guide plate.

[0025] Optionally, the end surface of the limiting portion away from the light guide main body is located in the avoidance groove.

[0026] Optionally, in the extension direction of the first side plate, the limiting portion is spaced apart from the inner wall of the avoidance groove.

[0027] Optionally, the distance between the limiting portion and the surface of the light guide body is greater than or equal to 0.4 mm.

[0028] According to a second aspect of the present application, a display terminal is provided, comprising the above-mentioned backlight module.

[0029] In the backlight module of the embodiment of the present application, an avoidance groove is provided on the side panel, and the limiting portion in the light guide plate is extended toward the avoidance groove to increase the distance between the edge of the optical film and the window area, thereby avoiding that part of the light is guided out from the edge of the optical film, thereby improving the technical problem of light leakage in the backlight module.

[0030] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] To more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0032] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same drawing numbers represent the same parts in the following description.

[0033] Figure 1 This is a structural diagram of the display module of this application;

[0034] Figure 2 is a partial cross-sectional view of the display module of this application;

[0035] Figure 3 This is a structural diagram of the backplane in the display module of this application;

[0036] Figure 4 This is a structural diagram of the light guide plate in the display module of this application;

[0037] Figure 5 yes Figure 1 The first structure of the back plate and the light guide plate in the middle area K;

[0038] Figure 6 yes Figure 1 The second structure of the back plate and light guide plate in the middle area K;

[0039] Figure 7 This is a structural diagram of the optical film in the display module of this application;

[0040] Figure 8 yes Figure 1 The first structure of the back plate, light guide plate and optical film in the middle area K;

[0041] Figure 9 yes Figure 1 The second structure of the back plate, light guide plate and optical film in the middle area K;

[0042] Figure 10a and Figure 10b The force distribution simulation diagram of each area of ​​the first mounting ear in this application when W1 is 1.85mm and 2.25mm respectively under mechanical vibration;

[0043] Figures 11a to 11d This is a simulation diagram of the force distribution in each area when the Wx of the first hanging ear in this application is 0.85W1, W1, 1.2W1 and 1.4W1 respectively when subjected to mechanical vibration. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0045] To improve the LCD module's tolerance to mechanical vibration in harsh environments, such as automotive applications, certain optical film structures, such as the mounting tabs, are susceptible to breakage. If these tabs break and enter the viewing area, they can cause undesirable effects such as dark shadows in the illuminated area.

[0046] Based on the above technical issues, please participate Figures 1 to 11d A backlight module 100 of the present application includes a back plate 10 , a light guide plate 20 and at least one optical film 30 .

[0047] In this embodiment, the back panel 10 includes a bottom panel 110 and a side panel 120 arranged on the periphery of the bottom panel 110, and the bottom panel 110 and the side panel 120 form a accommodating cavity; the light guide plate 20 includes a light guide main body 210 and a limiting portion 220 connected to the light guide main body 210, and the light guide main body 210 is located in the accommodating cavity and is spaced apart from the side panel 120.

[0048] In this embodiment, the optical film 30 is disposed on a side of the light guide body 210 away from the bottom plate 110 . A limiting groove 30 a is defined at an edge of the optical film 30 , and an inner wall of the limiting groove 30 a surrounds the limiting portion 220 .

[0049] In this embodiment, the multiple side panels 120 include a first side panel 121 arranged adjacent to the limiting portion 220, and the first side panel 121 is also provided with an avoidance groove 120a corresponding to the limiting portion 220, and at least part of the limiting portion 220 is located between the light guide main body 210 and the avoidance groove 120a.

[0050] The present application increases the distance between the edge of the optical film 30 and the window area VA by opening a avoidance groove 120a on the first side panel 121 and extending the limiting portion 220 in the light guide plate 20 toward the position of the avoidance groove 120a, thereby avoiding part of the light from being output from the edge of the optical film 30 and improving the technical problem of light leakage in the backlight module 100; at the same time, the increase in the area of ​​the optical film 30 in the non-window area NA is equivalent to increasing the area of ​​the hanging ear in the optical film 30, thereby increasing the strength of the hanging ear and avoiding the problem of the hanging ear breaking during mechanical vibration.

[0051] It should be noted that the backlight module 100 can be used to provide a backlight source for a liquid crystal panel, and the liquid crystal panel and the backlight module 100 are combined to form a liquid crystal display module.

[0052] Please note that Figure 2 The backlight module 100 includes a window area VA and a non-window area NA located outside the window area VA. The window area VA is the effective area of ​​the backlight module 100 for providing backlight to the display panel. The area outside the window area VA is the non-window area NA, that is, the edge area of ​​the backlight module 100, the side panel 120, and other areas are all located in the non-window area NA.

[0053] In this embodiment, the backlight module 100 is used to convert the light emitted by the light bar 40 into a planar light source.

[0054] In this example, see Figure 2 The backlight module 100 also includes a light bar 40 arranged between the light guide plate 20 and the second side plate 122. The light bar 40 includes a base 410 and a plurality of light-emitting units 420 arranged on the base 410. The light-emitting units 420 can be LEDs, such as MicroLEDs, MiniLEDs or LEDs of regular sizes. At the same time, a driving circuit for the light-emitting units 420 to emit light can be provided in the base 410.

[0055] It should be noted that the backlight module 100 of the present application may also be a direct-lit backlight module or an edge-lit backlight module. The following embodiments are described using the edge-lit backlight module as an example.

[0056] For example, see Figure 2 In an edge-type backlight module, the light bar 40 can be located at the edge of the light guide plate 20, the light emitted from the light-emitting unit 420 is incident on the side wall of the light guide plate 20, and the optical film 30 is stacked on the light guide plate 20.

[0057] In this embodiment, the light guide plate 20 is used to efficiently guide and propagate light emitted by the light source throughout the viewing area VA. The surface or interior of the light guide plate 20 typically has special structures or patterns, such as microstructures or dots. These structures scatter and reflect light during propagation, thereby evenly dispersing the light originally concentrated near the light source across the entire surface of the light guide plate 20, thereby forming a relatively uniform backlight source.

[0058] For a direct-lit backlight module, a plurality of light-emitting units 420 are mainly distributed on the bottom plate 110. Light emitted from the light source is directly incident on the optical film 30. The light guide plate 20 is omitted. There is a certain distance between the optical film 30 and the light-emitting units 420, thereby achieving light mixing.

[0059] See also Figure 2 The backlight module 100 further includes a reflective sheet, which is disposed on the side of the light guide plate 20 close to the bottom plate 110. The reflective sheet can reflect light that would otherwise be lost from the lower surface of the light guide plate 20 back to the light-emitting surface, thereby improving the light-emitting efficiency of the entire backlight module 100 and enhancing the brightness of the backlight module 100.

[0060] See also Figure 2 The backlight module 100 further includes a thermally conductive adhesive 430 disposed between the side panel 120 and the light bar 40 to guide the heat in the light bar 40 into the side panel 120 through the thermally conductive adhesive 430 to improve the heat dissipation efficiency of the light bar 40.

[0061] Please note that Figure 2 and Figure 3 The back panel 10 of the present application includes a bottom panel 110 and a plurality of side panels 120. The side panels 120 are connected to the edges of the bottom panel 110, and the bottom panel 110 and the side panels 120 form a box-like structure. The interior of the box-like structure forms a receiving cavity. For example, the plurality of side panels 120 of the present application may include two first side panels 121 disposed opposite each other and two second side panels 122 located between the two first side panels 121. The angle between the first side panels 121 and the second side panels 122 may be 90 degrees.

[0062] In some embodiments, the back plate 10 is made of metal, such as aluminum, etc.; and the back plate 10 of the present application may be a die-casting.

[0063] In this embodiment, the optical film 30 can be one or a combination of a diffuser, a prism, a brightness enhancement film, or an advanced light control film. For example, a diffuser is used to diffuse the light emitted by the backlight source, making it uniform, reducing brightness unevenness caused by uneven light distribution or optical components, and improving the uniformity of light output from the entire backlight module 100. A brightness enhancement film utilizes the refraction and total reflection principles of a prism to focus light within a specific angle range, thereby increasing the brightness in the normal viewing direction of the backlight module 100. Advanced light control film, based on ultra-fine louver optical technology, controls the angle of light through a parallel arrangement of grating structures (louvers), thereby narrowing the wide viewing angle of the backlight module 100, thereby achieving the purposes of preventing peeping, controlling reflected light, and improving the display contrast of the display module.

[0064] See also Figure 2The backlight module 100 may include multiple optical films 30. For example, the backlight module 100 of the present application may include a first optical film 310, a second optical film 320 and a third optical film 330. The first optical film 310 is arranged close to the light guide plate 20 and is attached to the light guide plate 20. The third optical film 330 is arranged away from the light guide plate 20. The second optical film 320 is arranged between the first optical film 310 and the third optical film 330.

[0065] In this embodiment, since the limiting portion 220 is mainly used to limit the optical film 30, the height of the limiting portion 220 of this application needs to be greater than or equal to the total thickness of multiple optical films 30, so that the limiting portion 220 provides a limiting function for each optical film 30.

[0066] In this embodiment, the optical film 30 includes any one of polycarbonate (PC), polyethylene terephthalate (PET), and other materials. For example, in this embodiment, the first optical film 310 may be a diffuser, the second optical film 320 may be a prism, and the third optical film 330 may be a brightness enhancement film; that is, the first optical film 310 and the second optical film 320 may be made of polyethylene terephthalate (PET), and the third optical film 330 may be made of polycarbonate (PC).

[0067] In this embodiment, when the backlight module 100 includes multiple optical films 30, the thickest optical film 30 is the heaviest and, when subjected to mechanical vibration, will shake most violently, making it most susceptible to breakage of the mounting tabs. Therefore, a relief groove 120a can be provided on the thickest optical film 30, and the optical film 30 can be extended into the area where the side panels 120 are located. This increases the area of ​​the thickest optical film 30 within the non-window area NA. This is equivalent to increasing the area of ​​the mounting tabs on the optical film 30, thereby increasing the strength of the mounting tabs and preventing breakage from mechanical vibration. Furthermore, the increased spacing between the window area VA and the edge of the optical film 30 also prevents light leakage from the product.

[0068] Among the multiple optical films 30 of the present application, the thickness of the optical film 30 away from the light guide plate 20 is greater than the thickness of the optical film 30 close to the light guide plate 20; for example, the thickness of the third optical film 330 of the present application is the largest, and the thickness of the second optical film 320 can be greater than or equal to the thickness of the first optical film 310.

[0069] In this embodiment, the PET material in the optical film 30 has high tensile strength, a low thermal expansion coefficient, and strong resistance to deformation. The PC material optical film 30 has low tensile strength, a large thermal expansion coefficient, and poor resistance to deformation. During vibration, the risk of fracture of the PC material optical film 30 is greater than that of the PET material optical film 30. Therefore, the present application prioritizes increasing the area of ​​the PC material within the non-window area NA.

[0070] See also Figure 2 The backlight module 100 further includes a middle frame 50 , which is disposed around the back plate 10 and covers the side plates 120 and a portion of the optical film 30 .

[0071] See also Figure 2 The backlight module 100 further includes an outer frame 60 located outside the middle frame 50 , and the outer frame 60 is used to accommodate the middle frame 50 and the back plate 10 .

[0072] It should be noted that the middle frame 50 and the outer frame 60 of the present application are only one embodiment, and are adaptively designed according to the narrow frame or other needs of the product.

[0073] In the following embodiments, the extension direction of the light bar 40 and the second side panel 122 is taken as the first direction X, the extension direction of the first side panel 121 is taken as the second direction Y, and the thickness direction of the light guide plate 20 is taken as the third direction Z. The plane in which the first direction X and the second direction Y are located is parallel to the light emitting surface of the light guide plate 20, and the third direction Z, the second direction Y and the first direction X are perpendicular to each other.

[0074] See also Figure 4 , the light guide main body 210 and the limiting part 220 of the present application can be set as an integral whole, or the limiting part 220 and the light guide main body 210 can be two structures; secondly, since the limiting part 220 of the present application is used to limit the optical film 30, the height of the limiting part 220 is greater than the thickness of the light guide main body 210, and the limiting part 220 is protruded from the side of the light guide main body 210 in the first direction X.

[0075] See also Figures 3 to 6 The first side panel 121 includes a first sub-panel 121a and a second sub-panel 121b connected to each other. The first sub-panel 121a and the second sub-panel 121b are arranged in the extension direction of the first side panel 121. In the thickness direction of the light guide plate 20, the height of the first sub-panel 121a is less than the height of the second sub-panel 121b.

[0076] In this embodiment, the avoidance groove 120a is provided on the first sub-plate 121a, and the avoidance groove 120a separates the first sub-plate 121a into a first sub-portion 121a1 and a second sub-portion 121a2 which are spaced apart from each other. The second sub-portion 121a2 is connected to the second sub-plate 121b, and the first sub-portion 121a1 and the second side plate 122 have an overlapping portion in the extension direction of the second side plate 122.

[0077] In this embodiment, the reduction in the height of the first sub-plate 121a allows the optical film 30 to extend to the surface of the first sub-plate 121a away from the bottom plate 110 during the shaking or expansion of the optical film 30 in the first direction X, thereby avoiding interference between the optical film 30 and the first side plate 121.

[0078] In this embodiment, the avoidance groove 120 a is provided so that the light guide plate 20 can rock along the first direction X when subjected to mechanical vibration, thereby avoiding interference between the limiting portion 220 and the first side plate 121 .

[0079] In this embodiment, the end face of the limiting portion 220 away from the light guide main body 210 can be located in the avoidance groove 120a, that is, part of the limiting portion 220 can be located in the avoidance groove 120a, which is equivalent to reducing the distance between the first side panel 121 and the light guide plate 20, further reducing the border width of the product, and realizing a narrow border design.

[0080] See also Figure 6 In the extension direction of the first side panel 121, the limiting portion 220 is spaced apart from the inner wall of the avoidance groove 120a; when part of the limiting portion 220 is located in the avoidance groove 120a, in order to avoid interference between the limiting portion 220 and the inner wall of the avoidance groove 120a, the present application can make the limiting portion 220 spaced apart from the inner wall of the avoidance groove 120a, for example, the distance L1 between the limiting portion 220 and the first sub-portion 121a1 can be greater than or equal to 0.3mm, and the distance L1 between the limiting portion 220 and the second sub-portion 121a2 can be greater than or equal to 0.3mm.

[0081] See also Figure 6 When part of the limiting portion 220 is located in the avoidance groove 120a, in order to avoid the limiting portion 220 being located on the outside of the first sub-plate 121a during mechanical vibration, the limiting portion 220 located in the avoidance groove 120a cannot be too much; for example, the limiting portion 220 is away from the surface of the light guide main body 210, and the distance L2 between the surface of the first side plate 121 away from the light guide main body 210 is greater than or equal to 0.4mm, that is, the present application needs to set a margin of at least 0.4mm to avoid the limiting portion 220.

[0082] In this embodiment, a dimension L3 of the avoidance groove 120a in the second direction Y may be greater than or equal to 3.5 mm.

[0083] See also Figures 7 to 9 The optical film 30 includes a first hanging ear 301 located on one side of the limiting portion 220, and the first hanging ear 301 extends toward the area where the first sub-portion 121a1 and the second side panel 122 are located, and the end surface of the first hanging ear 301 close to the first sub-portion 121a1 extends at least to between the first sub-portion 121a1 and the light guide main body 210.

[0084] Or / and, the optical film 30 includes a second hanging ear 302 located on the other side of the limiting portion 220, the second hanging ear 302 extends toward the area where the second sub-portion 121a2 is located, and the end face of the second hanging ear 302 close to the second sub-portion 121a2 extends at least to between the second sub-portion 121a2 and the light guide main body 210.

[0085] It should be noted that the first hanging ear 301 and the second hanging ear 302 of the present application are both provided to cooperate with the limiting portion 220 to limit the optical film 30 .

[0086] It should be noted that at least one of the first hanging ear 301 and the second hanging ear 302 of the present application can be provided, for example, Figure 7 In the structure, the optical film 30 described in the present application can be provided with the first hanging ear 301 and the second hanging ear 302 at the same time.

[0087] It should be noted that in Figure 7 In the structure, in order to ensure the limiting of the optical film 30, the optical film 30 of the present application is provided with the first hanging ear 301 and the second hanging ear 302 on both sides along the first direction X, and the limiting portion 220 is also provided on both sides of the light guide main body 210 in the first direction X.

[0088] It should be noted that Figure 7 The optical film 30 may be any one of the first optical film 310 , the second optical film 320 and the third optical film 330 of the present application.

[0089] In this embodiment, the length of the first hanging ear 301 in the extension direction of the first side plate 121 is greater than or equal to 2.25 mm.

[0090] In this embodiment, the length of the second hanging ear 302 in the extension direction of the first side plate 121 is greater than or equal to 2.25 mm.

[0091] See also Figure 8 In order to prevent the first hanging ear 301 and the second hanging ear 302 from breaking during mechanical vibration, the present application makes the length W1 of the first hanging ear 301 in the second direction Y greater than or equal to 2.25 mm, and the length W2 of the second hanging ear 302 in the second direction Y greater than or equal to 2.25 mm.

[0092] It should be noted that W1 and W2 in this application are mainly determined by the formula W≥3 0.5 *F*n / (t*σ γ ) is obtained, W is the length of the ear in the optical film 30 in the second direction Y; F is the shear force, that is, the maximum impact force on the optical film 30 under vibration; t is the thickness of the optical film 30, for example, the thickness of the optical film 30 of the present application can be 0.39 mm; σ γ It is the yield strength of the material under harsh conditions. For example, the yield strength of the optical film of this application under a high temperature environment of 3085°C is 16.24 MPa. n is the polarization of the fixture assembly in the three comprehensive vibrations, and the safety factor of the polarization acceleration of the product at the maximum position. For example, n can be 3 to 5.

[0093] It should be noted that the shear force F in this application can be obtained by the formula F=M*Grms*C, for example f1 and fn are frequency ranges, PSD(f) is the acceleration power spectrum density value, in m / s2, and the power spectrum density value of each stage corresponds to different frequency bands; C is the peak factor, which is mainly set according to the vibration environment, for example, C can be 3 to 5; M is the total mass of the optical diaphragm 30, in kg.

[0094] According to the above parameters, when W1 and W2 are both greater than or equal to 2.25 mm, the technical problem of the first hanging ear 301 and the second hanging ear 302 being broken during mechanical vibration can be avoided.

[0095] See also Figure 10a and Figure 10b The accompanying drawings provide numerical simulation diagrams of the force distribution in various regions under mechanical vibration when W1 is 1.85 mm and 2.25 mm, respectively. As can be seen from the figure, when W1 is 1.85 mm, the maximum force on the first hanging ear 301 is 17.605 MPa, which exceeds the maximum yield strength of the material itself; when W1 is 2.25 mm, the maximum force on the first hanging ear 301 is 14.443 MPa, which is less than the maximum yield strength of the material itself.

[0096] It should be noted that the first optical film 310, the second optical film 320 and the third optical film 330 of the present application can all include at least one of the first hanging ear 301 and the second hanging ear 302. For example, the first optical film 310, the second optical film 320 and the third optical film 330 of the present application can all include the first hanging ear 301 and the second hanging ear 302.

[0097] In this embodiment, the area of ​​the first hanging ear 301 in the optical film 30 away from the light guide plate 20 is larger than the area of ​​the first hanging ear 301 in the optical film 30 close to the light guide plate 20; or / and, the area of ​​the second hanging ear 302 in the optical film 30 away from the light guide plate 20 is larger than the area of ​​the second hanging ear 302 in the optical film 30 close to the light guide plate 20.

[0098] With respect to the first optical film 310, the second optical film 320, and the third optical film 330 of the present application, since the third optical film 330 has the largest thickness, when subjected to mechanical vibration, the third optical film 330 shakes most violently and is most likely to have its ears broken. Therefore, the present application maximizes the area of ​​the first ear 301 and the second ear 302 in the third optical film 330, that is, the surface of the first ear 301 and the second ear 302 in the third optical film 330 close to the first side surface exceeds the surface of the first ear 301 and the second ear 302 in the first optical film 310 and the second optical film 320 close to the first side surface.

[0099] Therefore, for the plurality of optical films 30 of the present application, the areas of the first hanging ear 301 and the second hanging ear 302 of the thicker optical film 30 are larger than those of the thinner optical film 30.

[0100] See also Figure 8 The limiting groove 30a is arranged around the limiting portion 220, that is, the limiting groove 30a and the limiting portion 220 are spaced apart. For example, in the second direction Y, the spacing between the limiting portion 220 and the two side walls of the limiting groove 30a can be equal. Considering the installation tolerance of the limiting groove 30a and the limiting portion 220, the spacing between the limiting portion 220 and the two side walls of the limiting groove 30a of the present application can be greater than or equal to 0.1 mm.

[0101] At the same time, considering the expansion amount of the optical film 30, in the first direction X, the distance between the limiting portion 220 and the side wall of the limiting groove 30a can be set to be larger, and the specific value can be determined according to the expansion gap, processing tolerance, assembly tolerance, etc. of the optical film 30; for example, the expansion amount of the third optical film 330 is large, so the distance between the limiting groove 30a of the third optical film 330 and the limiting portion 220 in the second direction Y can be set to be larger.

[0102] In this embodiment, the distance between the side of the first hanging ear 301 and / or the second hanging ear 302 close to the first side plate 121 and the light guide body 210 is smaller than the distance between the side of the limiting portion 220 close to the first side plate 121 and the light guide body 210.

[0103] See also Figure 8 Since the limiting groove 30a between the first hanging ear 301 and the second hanging ear 302 needs to match the limiting portion 220, the end surfaces of the first hanging ear 301 and the second hanging ear 302 close to the first side panel 121 of the present application cannot exceed the side surface of the limiting portion 220 close to the first side panel 121; for example, the end surfaces of the first hanging ear 301 and the second hanging ear 302 close to the first side panel 121 can both extend to between the first side panel 121 and the light guide main body 210 and the first side panel 121.

[0104] See also Figure 8 The distance L4 between the side of the first hanging ear 301 and the second hanging ear 302 close to the first side panel 121 and the side of the limiting portion 220 close to the first side panel 121 is equivalent to the overlapping width L4 between the first hanging ear and / or the second hanging ear and the limiting portion in the extension direction of the second side panel, and the overlapping width L4 needs to be greater than or equal to 2 mm to avoid the first hanging ear 301 and the second hanging ear 302 being too small around the limiting portion 220, resulting in the limiting portion 220 being unable to effectively limit the optical film 30.

[0105] See also Figure 4 and Figure 8 Since the light guide plate 20 needs to be limited in the second direction Y, the two ends of the light guide main body 210 of the present application are provided with protrusions 230 extending toward the light bar 40. Since the light guide plate 20 has a certain amount of expansion, the protrusions 230 and the base 410 of the present application can be arranged at intervals.

[0106] In this embodiment, a buffer pad 440 may be provided on the surface of the base 410 facing the light guide main body 210. The buffer pad 440 contacts the protrusion 230. The cooperation between the buffer pad 440 and the protrusion 230 can limit the light guide plate 20 in the second direction Y. At the same time, the expansion and contraction of the buffer pad 440 can compensate for the expansion of the light guide plate 20.

[0107] In this embodiment, the distance between the surface of the first sub-board 121a away from the bottom board 110 and the bottom board 110 is greater than the distance between the surface of the light guide body 210 away from the bottom board 110 and the bottom board 110 .

[0108] Since multiple optical films 30 need to be set on the surface of the light-guiding main body 210 away from the base plate 110, the surface of the light-guiding main body 210 away from the base plate 110 in the present application needs to be lower than the surface of the first sub-plate 121a away from the base plate 110; at the same time, since the surface of the third optical film 330 close to the first side plate 121 is close to the first side plate 121, in order to avoid the first hanging ear 301 and the second hanging ear 302 in the third optical film 330 from interfering with the first side plate 121, the surface of the first sub-plate 121a of the present application needs to be lower than the surface of the third optical film 330 close to the base plate 110.

[0109] See also Figure 8 In the extension direction of the first side panel 121, the second hanging ear 302 is spaced apart from the second sub-panel 121b, and the first hanging ear 301 and the light bar 40 are spaced apart; in the installation process of the optical film 30, in order to avoid interference between the optical film 30 and the first sub-panel 121a and the second side panel 122, the first hanging ear 301 of the present application needs to be spaced apart from the light bar 40, for example, the distance L5 between the first hanging ear 301 and the light bar 40 in the second direction Y can be greater than or equal to 0.2 mm, and the distance between the second hanging ear 302 and the second sub-panel 121b in the second direction Y can be greater than or equal to 0.2 mm.

[0110] In this embodiment, the distance between the side surface of the optical film 30 close to the light bar 40 and the light bar 40 is greater than the distance between the light guide body 210 and the light bar 40 .

[0111] See also Figures 7 to 9In the present application, each optical film 30 is provided with a avoidance opening 30b on the side close to the light bar 40, and the distance between the inner wall of the avoidance opening 30b and the light bar 40 in the second direction Y is greater than the distance between the surface of the light guide main body 210 close to the light bar 40 and the light bar 40.

[0112] At the same time, since the first optical film 310, the second optical film 320 and the third optical film 330 of the present application are installed along the third direction Z, in order to ensure the position accuracy of each optical film 30 during installation, the depth of the avoidance opening 30b of the first optical film 310 in the second direction Y is less than the depth of the avoidance opening 30b of the first optical film 310 in the second direction Y, and the depth of the avoidance opening 30b of the second optical film 320 in the second direction Y is less than the depth of the avoidance opening 30b of the third optical film 330 in the second direction Y, that is, in the top view direction, the side surface of the light guide body 210 close to the light bar 40, the inner wall of the avoidance opening 30b in the first optical film 310, the inner wall of the avoidance opening 30b in the second optical film 320, and the inner wall of the avoidance opening 30b in the third optical film 330 can be shown in sequence.

[0113] See also Figure 7 Since the optical film 30 is provided with the avoidance opening 30b, there is a smaller area between the avoidance opening 30b and the limiting groove 30a. When the optical film 30 is subjected to mechanical vibration, the first hanging ear 301 in this area is subjected to the greatest force, which can easily cause the first hanging ear 301 to break. Therefore, this area needs to have a sufficient width.

[0114] For example, the side of the limiting groove 30a close to the avoidance opening 30b has a first arc, and the side of the avoidance opening 30b close to the limiting groove 30a has a second arc, and the ratio of the dimension Wx of the line connecting the first center M1 of the first arc and the second center M1 of the second arc on the first hanging ear 301 to the length of the first hanging ear 301 in the extension direction of the first side plate 121 is greater than or equal to 1.2; please refer to Figures 11a to 11d , the force simulation diagram when Wx is 0.85W1, W1, 1.2W1 and 1.4W1 respectively.

[0115] exist Figure 11a In the embodiment, the maximum force of the first hanging ear 301 is 17.019 MPa; Figure 11b In the embodiment, the maximum force of the first hanging ear 301 is 14.716 MPa; Figure 11c In the embodiment, the maximum force of the first hanging ear 301 is 12.628 MPa; Figure 11dIn the embodiment, the maximum force of the first hanging ear 301 is 11.453 MPa.

[0116] Since the yield strength of the material of the optical film 30 is 16.24 MPa, Wx satisfies the condition when W1, 1.2W1 and 1.4W1 respectively. Considering the safety factor, Wx satisfies the condition when 1.2W1 and 1.4W1 respectively. Therefore, Wx in this application needs to be greater than or equal to 1.2W1.

[0117] See also Figure 4 The light guide plate 20 further includes a positioning structure 240 , which is disposed close to the light bar 40 , and the positioning structure 240 and the limiting portion 220 can be integrally disposed with the light guide body 210 .

[0118] See also Figure 1 The positioning structure 240 can be arranged in the middle position of the light guide plate 20, and the height of the positioning structure 240 can be greater than the height of the limiting portion 220. A positioning hole 50a corresponding to the positioning structure 240 is opened on the middle frame 50, and the positioning structure 240 is sleeved in the positioning hole 50a.

[0119] It should be noted that grooves corresponding to the positioning structures 240 may be further provided on the plurality of optical films 30 , and the positioning structures 240 pass through the grooves on the optical films 30 and are sleeved in the positioning holes 50 a .

[0120] See also Figure 1 and Figure 3 The middle frame 50 is further provided with a plurality of positioning grooves 50b, and the surface of the side panels 120 away from the light guide plate 20 is provided with a plurality of bosses 120b, one boss 120b corresponds to one positioning groove 50b, and the boss 120b is embedded in the positioning groove 50b.

[0121] According to a second aspect of the present application, the present application provides a display terminal, which may include the above-mentioned backlight module; at the same time, the display terminal may include a backlight module and a liquid crystal panel, and the backlight module and the liquid crystal panel are combined into one.

[0122] In this embodiment, the display terminal can be any product or component with a display function, such as a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, or a car display screen.

[0123] The present application relates to a backlight module and a display terminal; the backlight module includes a back panel and a light guide plate and an optical film located inside the back panel, the light guide plate includes a light guide main body and a limiting part, a limiting groove is provided on the edge of the optical film, and the inner wall of the limiting groove is arranged around the limiting part, and an avoidance groove corresponding to the limiting part is also provided on the side panel, and at least part of the limiting part is located between the light guide main body and the avoidance groove; the present application increases the area of ​​the optical film in the non-window area by providing an avoidance groove on the side panel and extending the limiting part in the light guide plate toward the avoidance groove, which is equivalent to increasing the area of ​​the hanging ear in the optical film, thereby avoiding the problem of the hanging ear breaking. At the same time, the increase in the distance between the window area and the edge of the optical film also avoids the technical problem of light leakage in the product.

[0124] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0125] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0126] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0127] The above description is merely a preferred embodiment of the present application and does not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A backlight module, characterized in that: include: A back plate, comprising a bottom plate and side plates arranged on the periphery of the bottom plate, wherein the bottom plate and the side plates form a receiving cavity; a light guide plate comprising a light guide body and a limiting portion connected to the light guide body, wherein the light guide body is located in the accommodating cavity and is spaced apart from the side plate; At least one optical film is disposed on a side of the light guide body away from the bottom plate, wherein a limiting groove is defined at an edge of the optical film, and an inner wall of the limiting groove is disposed around the limiting portion; Among them, the multiple side panels include a first side panel arranged adjacent to the limiting portion, and the first side panel is also provided with an avoidance groove corresponding to the limiting portion, and at least part of the limiting portion is located between the light guide body and the avoidance groove.

2. The backlight module according to claim 1, wherein: The first side plate includes a first sub-plate and a second sub-plate arranged along an extension direction of the first side plate, and in a thickness direction of the light guide plate, a height of the first sub-plate is smaller than a height of the second sub-plate; The avoidance groove is provided on the first sub-board, and the avoidance groove separates the first sub-board into a first sub-portion and a second sub-portion which are spaced apart from each other, and the second sub-portion is connected to the second sub-board.

3. The backlight module according to claim 2, wherein: The plurality of side panels further include a second side panel disposed adjacent to the first side panel, and the first sub-portion and the second side panel have an overlapping portion in an extending direction of the second side panel; The optical film includes a first hanging ear located on one side of the limiting portion, the first hanging ear extends toward the area where the first sub-portion and the second side panel are located, and the end surface of the first hanging ear close to the first sub-portion extends at least to between the first sub-portion and the light guide body; or / and, The optical film includes a second hanging ear located on the other side of the limiting portion, the second hanging ear extends toward the second sub-portion, and the end surface of the second hanging ear close to the second sub-portion extends at least to between the second sub-portion and the light guide body portion.

4. The backlight module according to claim 3, wherein: A length of the first hanging ear in an extension direction of the first side plate is greater than or equal to 2.25 mm.

5. The backlight module according to claim 3, wherein: A length of the second hanging ear in an extension direction of the first side plate is greater than or equal to 2.25 mm.

6. The backlight module according to claim 3, wherein: An overlapping width between the first hanging ear and / or the second hanging ear and the limiting portion in the extension direction of the second side plate is greater than or equal to 2 mm.

7. The backlight module according to claim 3, wherein: The backlight module further includes a light bar disposed between the light guide plate and the second side plate, wherein the light bar includes a base and a plurality of light-emitting units disposed on the base; Wherein, protrusions extending toward the light bar are provided at both ends of the light guide main body, and the protrusions and the base are spaced apart.

8. The backlight module according to claim 7, wherein: A buffer pad is provided on a surface of the base facing the light guide main body, and the buffer pad is in contact with the protrusion.

9. The backlight module according to claim 7, wherein: In the extension direction of the first side panel, the second hanging ear and the second sub-board are spaced apart, and the first hanging ear and the light bar are spaced apart.

10. The backlight module according to claim 7, wherein: The distance between the side surface of the optical film close to the light bar and the light bar is greater than the distance between the light guide body and the light bar.

11. The backlight module according to claim 3, wherein: The backlight module includes a plurality of optical films arranged in a stacked manner, the area of ​​the first hanging ear in the optical film away from the light guide plate is larger than the area of ​​the first hanging ear in the optical film close to the light guide plate, or / and the area of ​​the second hanging ear in the optical film away from the light guide plate is larger than the area of ​​the second hanging ear in the optical film close to the light guide plate.

12. The backlight module according to claim 7, wherein: The optical film is provided with a avoidance opening on the side close to the light bar, the limiting groove is provided with a first arc on the side close to the avoidance opening, and the avoidance opening is provided with a second arc on the side close to the limiting groove. The ratio of the size of the line connecting the first center of the first arc and the second center of the second arc on the first hanging ear to the length of the first hanging ear in the extension direction of the first side panel is greater than or equal to 1.

2.

13. The backlight module according to any one of claims 1 to 12, characterized in that: The backlight module includes a plurality of stacked optical films, and the thickness of the optical films away from the light guide plate is greater than the thickness of the optical films close to the light guide plate.

14. The backlight module according to any one of claims 1 to 12, characterized in that: The end surface of the limiting portion away from the light guide main body is located in the avoidance groove.

15. The backlight module according to any one of claims 1 to 12, characterized in that: In the extending direction of the first side plate, the limiting portion is spaced apart from the inner wall of the avoidance groove.

16. The backlight module according to any one of claims 1 to 12, characterized in that: The limiting portion is away from the surface of the light guide body, and the distance between the limiting portion and the surface of the first side plate away from the light guide body is greater than or equal to 0.4 mm.

17. A display terminal, characterized in that: The backlight module comprises the backlight module according to any one of claims 1 to 16.

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