Backlight module and display device

Abstract

The present application relates to a kind of backlight module, including backboard and the light guide plate contained in backboard, the light exit surface of light guide plate is provided with at least two layers of optical film material, backboard includes bottom plate and the side wall formed by the extension of the four peripheral edges of bottom plate, first gap is formed on each side wall;Each layer of optical film material has the limiting structure capable of being contained in first gap, fixed part is arranged on the limiting structure, at least two layers of optical film material include the first optical film material away from light guide plate and the second optical film material close to light guide plate, hollow part is arranged on the limiting structure of first optical film material, the orthographic projection on second optical film material is located in the fixed part of first optical film material, to expose the fixed part of second optical film material;Backlight module further includes fixing adhesive tape, fixing adhesive tape includes the first part for being bonded with the fixed part of at least two layers of optical film material, and the second part is connected with the side of side wall away from light guide plate.The present application also relates to a kind of display device.

Description

Technical Field

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

[0002] Backlight modules typically include a light guide plate and multiple layers of optical film on the light-emitting side of the light guide plate. To fix the optical film, stepped tape is set on the edge of the light guide plate. In the light-emitting direction of the light guide plate, the stepped surfaces at different heights are bonded and fixed to different layers of optical film. When there are many optical films, the manufacturing difficulty of the tape increases, and the stepped surfaces of the tape need to have a certain width; otherwise, the optical film cannot be fixed firmly, limiting the narrow bezel design. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a backlight module and a display device that solves the problem of increasing the manufacturing difficulty of the tape when there are many layers of optical film material when fixing optical film material with stepped tape, and also limits the narrow bezel.

[0004] To achieve the above objectives, the technical solution adopted in this embodiment of the invention is: a backlight module, including a back plate and a light guide plate housed within the back plate, wherein the light-emitting surface of the light guide plate is provided with at least two layers of optical film.

[0005] The back plate includes a bottom plate and sidewalls extending from the periphery of the bottom plate, each sidewall having an end face away from the bottom plate, and at least one portion of the end face being recessed toward the bottom plate to form a first notch on the respective sidewall.

[0006] Each layer of the optical film has a limiting structure that can be accommodated within the first notch. The limiting structure is provided with a fixing part. At least two layers of the optical film include a first optical film disposed away from the light guide plate and a second optical film disposed close to the light guide plate. The limiting structure of the first optical film is provided with a hollow part. The orthographic projection of the hollow part on the second optical film is located within the fixing part of the first optical film, so as to expose the fixing part of the second optical film.

[0007] The backlight module further includes a fixing tape for connecting to the fixing portion of each optical film to fix the at least two optical film layers. The fixing tape includes a first portion for bonding and fixing to the at least two optical film layers and a second portion for connecting to the side of the sidewall away from the light guide plate.

[0008] Optionally, the fixing portions of each pair of adjacent optical film layers are staggered to form a stepped structure.

[0009] Optionally, the second optical film material includes a first body, and a portion of at least one side of the first body extends outward to form the limiting structure. In a first direction, at least one side of the limiting structure of the second optical film material has a second notch at the connection with the first body. The first direction is parallel to the extension direction of the sidewall and perpendicular to the light emission direction of the light guide plate.

[0010] Optionally, the cross-sectional shape of the second notch is semi-circular in the direction parallel to the second optical film material.

[0011] Optionally, the first optical film includes a second body, and a portion of at least one side of the second body extends outward to form the limiting structure. In the first direction, at least one side of the limiting structure of the second optical film has a third notch at the connection between it and the second body.

[0012] Optionally, the cross-sectional shape of the third notch is semi-circular in the direction parallel to the first optical film material.

[0013] Optionally, in the first direction, the hollow portion is located in the middle of the limiting structure.

[0014] Optionally, there is a seam between the first part and the second part.

[0015] Optionally, the first part includes a first sub-part and a second sub-part arranged sequentially along a direction away from the second part. The length of the second sub-part in the first direction is greater than the length of the first notch in the first direction. The first direction is parallel to the extension direction of the sidewall and perpendicular to the light emission direction of the light guide plate.

[0016] Optionally, the length of the first sub-part in the first direction is less than the length of the first notch in the first direction.

[0017] Optionally, the length of the first sub-part in the first direction is the same as the length of the second part in the first direction.

[0018] Optionally, the first notch is located at the middle of the sidewall along its extension direction.

[0019] This invention also provides a display device including the backlight module described above.

[0020] The beneficial effects of the present invention are as follows: a notch is provided on the side wall of the back plate, each layer of optical film has a fixing part at least partially accommodated in the notch, and a hollow part is provided on the first optical film disposed away from the light guide plate to expose the fixing part of the second optical film disposed near the light guide plate, which facilitates the fixing of the adhesive tape, and a part of the adhesive tape is connected to the fixing part, and the other part of the adhesive tape can pass through the notch and be connected to the side wall of the back plate, thereby improving the connection stability of the optical film and thus achieving a narrow bezel. Attached Figure Description

[0021] Figure 1 This diagram illustrates the structure of a backlight module in the relevant technology. Figure 1 ;

[0022] Figure 2 This diagram illustrates the structure of a backlight module in the relevant technology. Figure 2 ;

[0023] Figure 3 This diagram illustrates the structure of a backlight module in the relevant technology. Figure 3 ;

[0024] Figure 4 This is a schematic diagram showing the structure of the backlight module in an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram showing the structure of the back plate in an embodiment of the present invention;

[0026] Figure 6 express Figure 5 A magnified view of a portion of the image;

[0027] Figure 7 A schematic diagram showing the structure of the diffusion membrane;

[0028] Figure 8 A schematic diagram showing the assembly of the diffusion membrane and the backing plate;

[0029] Figure 9 A schematic diagram showing the structure of the prism membrane;

[0030] Figure 10 A schematic diagram showing the structure after the prism film, diffusion film and backplate are assembled;

[0031] Figure 11 A schematic diagram showing the structure of the brightness enhancement film;

[0032] Figure 12 A schematic diagram showing the assembled structure of the brightness enhancement film, prism module, diffusion film, and backplate;

[0033] Figure 13 This diagram shows the structure of the adhesive tape.

[0034] Figure 14This diagram illustrates the state of the optical film material being fixed with adhesive tape.

[0035] Figure 15 express Figure 14 A magnified view of a portion of the image.

[0036] 1. Adhesive tape; 2. Back plate; 3. Optical film material; 31. Diffuser film; 32. Prism film; 33. Brightness enhancement film; 4. Light guide plate; 5. Adhesive frame; 10. Fixing tape; 21. Base plate; 22. Side wall; 201. First notch; 301. First main body; 302. First limiting structure; 303. Second notch; 321. Second main body; 322. First hollow part; 323. First sub-limiting part; 324. Third notch; 331. Third main body; 332. Second hollow part; 333. Second sub-limiting part; 334. Fourth notch; 101. First part; 102. Second part; 1011. First sub-part; 1012. Second sub-part; 1013. First lug; 1014. Second lug. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0038] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] like Figure 1 , Figure 2 and Figure 3 As shown, in related technologies, the optical film 3 is fixed by a stepped adhesive tape 10 disposed on the edge of the light guide plate 4. The stepped adhesive tape 10 has a first connecting surface that connects to the light guide plate 4 and a second connecting surface that is disposed opposite to the first connecting surface. The second connecting surface includes a plurality of stepped surfaces corresponding to the number of layers of the optical film 3. Figure 1 and Figure 2In this design, three layers of optical film are stacked on the light-emitting side of the light guide plate 4. Correspondingly, three stepped surfaces are provided on the second connecting surface. When the number of layers of optical film 3 is large, it increases the manufacturing difficulty of the adhesive tape 10. In order to improve the connection stability of the optical film 3, it is necessary to increase the connection area between the adhesive tape 10 and the corresponding optical film 3, that is, in the direction parallel to the light-emitting surface of the light guide plate 4 (refer to...). Figure 3 The tape 10 (shown in the Y direction) needs to have a certain width. If the tape 10 is close to the visible area of ​​the backlight module, uneven black edges are likely to appear. To avoid this phenomenon, the edge of the tape 10 needs to be a certain distance from the visible area of ​​the backlight module, which will limit the setting of the narrow bezel.

[0040] refer to Figures 4-15 To address the aforementioned technical problems, this embodiment provides a backlight module, including a backplate 2 and a light guide plate 4 housed within the backplate 2. The light-emitting surface of the light guide plate 4 is provided with at least two layers of optical film 3.

[0041] The back plate 2 includes a bottom plate 21 and sidewalls 22 extending from the periphery of the bottom plate 21. Each sidewall 22 has an end face away from the bottom plate 21, and a portion of at least one end face is recessed toward the bottom plate 21 to form a first notch 201 on the corresponding sidewall 22.

[0042] Each layer of optical film 3 has a limiting structure that can be accommodated within the first notch 201. The limiting structure is provided with a fixing part. At least two layers of optical film 3 include a first optical film disposed away from the light guide plate 4 and a second optical film disposed close to the light guide plate 4. The limiting structure of the first optical film is provided with a hollow part. The orthographic projection of the hollow part on the second optical film is located within the fixing part of the first optical film, so as to expose the fixing part of the second optical film.

[0043] The backlight module also includes a fixing tape 10, which is used to connect to the fixing part of each optical film 3 to fix the at least two optical film 3. The fixing tape 10 includes a first part 101 for bonding and fixing to the at least two optical film 3, and a second part 102 connected to the side of the sidewall 22 away from the light guide plate 4.

[0044] In this embodiment, a cutout is provided on the first optical film material located away from the light guide plate 4 to expose the fixing portion of the second optical film material located near the light guide plate 4, facilitating the fixing of the adhesive tape 10. A first notch 201 is provided on the side wall 22 of the back plate 2. Each layer of the optical film material 3 has a fixing portion at least partially accommodated at the first notch 201, and a portion of the adhesive tape 10 is connected to the fixing portion. Another portion of the adhesive tape 10 can pass through the notch and connect to the side wall 22 of the back plate 2, improving the connection stability of the optical film material 3.

[0045] Furthermore, in this embodiment, the fixed optical film 3 utilizes the width of the sidewall 22 of the back plate 2, thereby achieving a narrow bezel. For specific comparisons... Figure 3 and Figure 4 , Figure 3 This is a schematic diagram of the structure of a backlight module in related technologies. Figure 4 This is a schematic diagram of the backlight module in an embodiment of the present invention. Figure 3 The fixing tape 10 is completely set on the light-emitting side of the light guide plate 4. The side wall 22 of the back plate 2 surrounds the side of the light guide plate 4 and the side of the optical film 3. In order to ensure that the optical film 3 is firmly fixed, the tape 10 needs to have a certain distance in the first direction. In order to avoid uneven black edges, the tape 10 also needs to have a certain distance from the visible area of ​​the backlight module. This restricts the setting of the narrow bezel. In the first direction, the width L1 of the bezel of the backlight module is L1 = a + c1 + b1 + g + e + d + f, where a is the distance between the edge of the visible area of ​​the backlight module and the edge of the effective display area, c1 is the distance between the tape 10 and the visible area of ​​the backlight module, b1 is the width of the tape 10, g is the gap between the side wall 22 of the back plate 2 and the optical film 3, e is the width of the side wall 22 of the back plate 2, d is the gap between the side wall 22 of the back plate 2 and the frame 5, and f is the width of the frame 5. Figure 4 In this design, due to the notch in the side wall 22 of the back panel 2, part of the fixing tape 10 covers the side wall 22 of the back panel 2, and part of the fixing tape 10 covers the optical film 3. That is, the fixing tape 10 utilizes the side wall 22 of the back panel 2, which not only facilitates the realization of a narrow bezel but also improves the connection stability between the tape 10 and the optical film 3. In the first direction, the width L of the backlight module's bezel is L = a + c + b + g + f, where c represents the distance from the fixing tape 10 to the visible area of ​​the backlight module, and b represents the width of the fixing tape 10. (Comparison) Figure 3 The width L1 of the bezel of the backlight module in the middle and Figure 4 The width L of the bezel of the backlight module in the image has the same values ​​for a, d, e, f, and g. This is to ensure that... Figure 3 Backlight module and Figure 4To achieve the same optical effect as the backlight module (the black edge of the fixing tape 10 is not visible from a wide viewing angle), set c = c1; in order to make Figure 3 Optical film material 3 and Figure 4 The optical film material 3 in the embodiment has the same fixing effect. The fixed width of the optical film material 3 is set to be consistent, i.e., b = b1. Then, it can be clearly obtained that: ΔL = L1 - L = e + d. Compared with the backlight module in related technologies, the bezel of the backlight module in this embodiment is reduced by e + d. Typically, the thickness of the back cover (back panel 2) of an automotive product is set according to the size of the product. For example, the thickness of the back panel 2 can be 0.8–1.2 mm, i.e., e = 0.8–1.2 mm. Then, the bezel of the backlight module can be effectively reduced by 0.9–1.3 mm, which is beneficial for achieving a narrow bezel.

[0046] In this embodiment, the first notch 201 can limit the optical film 3. Compared with the related technology, which sets a convex hull on the light guide plate 4, the structure is simplified.

[0047] The location of the first notch 201 can be set according to actual needs. In some embodiments of the present invention, the first notch 201 is located at the middle of the side wall 22 of the back plate 2 along its extension direction, which is beneficial for the optical film 3 to expand towards the opposite ends of the first notch 201. The first notch 201 is located in the extension direction of the side wall (refer to...). Figure 6 The length L2 in the X direction can be determined according to the scale and the number of fixed optical films 3, as shown in the reference. Figure 5 and Figure 6 .

[0048] In some embodiments of this example, the fixing portions of each pair of adjacent optical film materials 3 are staggered to form a stepped structure.

[0049] In this embodiment, the fixing tape 10 fixes the multiple layers of optical film 3 by directly attaching it to the optical film 3 from the side away from the light guide plate 4. By adopting the above solution, each layer of optical film 3 can be better fixed.

[0050] In some embodiments of this example, the second optical film material includes a first body, and a portion of at least one side of the first body extends outward to form the limiting structure. In a first direction, at least one side of the limiting structure of the second optical film material has a second notch at the connection point with the first body. The first direction is parallel to the extension direction of the sidewall 22 and perpendicular to the light emission direction of the light guide plate 4.

[0051] The limiting structure cooperates with the first notch 201 to limit the second optical film material, and the setting of the second notch serves to prevent mistaken identity.

[0052] The shape of the second notch can be varied. For example, in the direction parallel to the second optical film, the cross-sectional shape of the second notch is semi-circular, but it is not limited to this.

[0053] refer to Figure 7 and Figure 8 The diffusion membrane 31 described herein has a first body 301 and a first limiting structure 302, in the extending direction of the sidewall (refer to...). Figure 7 In the X direction, a second notch 303 is provided at the connection between one side of the first limiting structure 302 and the first body 301.

[0054] In some embodiments of this example, the first optical film material includes a second body, and a portion of at least one side of the second body extends outward to form the limiting structure. In the first direction, at least one side of the limiting structure of the second optical film material has a third notch at the connection point with the second body.

[0055] The limiting structure is designed to work in conjunction with the second notch to limit the first optical film material, and the third notch serves to prevent mistaken insertion.

[0056] The shape of the third notch can be varied. For example, in the direction parallel to the first optical film, the cross-sectional shape of the third notch is semi-circular, but it is not limited to this.

[0057] In this embodiment, exemplarily, the cutout portion is located in the middle of the limiting structure in the first direction, but this is not a limitation. The cutout portion is designed to expose the fixing portion of the optical film 3 located near the light guide plate 4, so as to facilitate fixing with the fixing tape 10. However, since the cutout portion is located on the limiting structure, both ends in the first direction need to be limited. Therefore, the cutout portion cannot be located at the edge of the limiting structure. That is to say, in the first direction, both opposite sides of the cutout portion have limiting portions for limiting.

[0058] The number of optical film materials 3 can be set according to actual needs, such as 3 layers, 4 layers, etc. In some embodiments of this example, the light guide plate 4 is provided with 3 layers of optical film materials 3 on the light-emitting side, and Diffuser (diffuser film 31), Prism (prism film 32), and DBEF (dual brightness enhancement film 33) are stacked sequentially along the direction away from the light guide plate 4.

[0059] A first limiting structure 302 is provided on the diffusion film 31, in the first direction (reference) Figure 7 In the X direction, the length of the first limiting structure matches the length L2 of the first notch 201, that is, the first limiting structure is accommodated in the first notch 201 and plays a limiting role for the diffusion film 31.

[0060] refer to Figure 9 and Figure 10 The prism film includes a second body 321, a limiting structure, and a first hollow portion 322. The prism film 32 is located on the side of the diffusion film 31 away from the light guide plate 4. The limiting structure is provided on the prism film 32, and the limiting structure has a hollow portion (first hollow portion 322). In the extending direction of the side wall 22, first sub-limiting portions 323 are respectively provided on opposite sides of the first hollow portion 322. In the extending direction of the side wall 22, a third notch 324 is provided at the connection between one side of the limiting structure and the second body 321. The orthographic projection of the first hollow portion 322 on the diffusion film 31 is located within the fixing portion of the diffusion film 31, so as to expose the fixing portion of the diffusion film 31 (reference). Figure 10 (The area exposed in the text).

[0061] refer to Figure 11 and Figure 12 The brightness enhancement film 33 is located on the side of the prism film 32 away from the light guide plate 4. The brightness enhancement film 33 includes a third main body 331 and a limiting structure. The limiting structure is provided with a hollow portion (second hollow portion 322). In the extension direction of the side wall, second sub-limiting portions 333 are respectively provided on opposite sides of the second hollow portion 322 to effectively limit the brightness enhancement film 33. In the extension direction of the side wall, a fourth notch 334 is provided at the connection between one side of the limiting structure and the third main body 331. The orthographic projection of the second hollow portion 332 on the prism film 32 is located in the fixing portion of the prism film 32 to expose the fixing portion of the prism film 32.

[0062] refer to Figures 13-15 In this embodiment, for example, there is a seam 103 between the first part 101 and the second part 102.

[0063] The seam 103 is provided to facilitate bending during assembly and to prevent the fixing tape 10 from lifting, especially when considering reliability in the face of temperature changes.

[0064] In this embodiment, the first part 101 includes a first sub-part 1011 and a second sub-part 1012 arranged sequentially along a direction away from the second part 102. The length L3 of the second sub-part 1012 in the first direction is greater than the length of the first notch 201 in the first direction. The first direction is parallel to the extension direction of the sidewall 22 and perpendicular to the light emission direction of the light guide plate 4.

[0065] The second sub-part 1012 and the first sub-part 1011 form a T-shaped structure, which facilitates the application of the fixing tape 10. The second sub-part 1012 has a first end and a second end opposite to each other in the first direction. The first end has a first lug 1013 exposed outside the first sub-part 1011, and the second end has a second lug 1014 exposed outside the first sub-part 1011. The first lug 1013 and the second lug 1014 have the same structure. In the first direction, the length of the first lug 1013 is 1.5 to 2 mm.

[0066] In this embodiment, for example, the length L4 of the first sub-part 1011 in the first direction is less than the length L2 of the first notch 201 in the first direction to avoid interference.

[0067] In this embodiment, for example, the length of the first sub-part 1011 in the first direction is the same as the length of the second part 102 in the first direction, that is, the fixing tape 10 has a T-shaped structure, which facilitates the application of the tape 10 and simplifies the structure.

[0068] This invention also provides a display device including the backlight module described above.

[0069] The display device can be any product or component with display function, such as an LCD TV, LCD monitor, digital photo frame, mobile phone, or tablet computer. The display device also includes a flexible circuit board, a printed circuit board, and a backplate 2.

[0070] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A backlight module, comprising a backplate and a light guide plate housed within the backplate, wherein the light-emitting surface of the light guide plate is provided with at least two layers of optical film, characterized in that, The back plate includes a bottom plate and sidewalls extending from the periphery of the bottom plate, each sidewall having an end face away from the bottom plate, and at least one portion of the end face being recessed toward the bottom plate to form a first notch on the respective sidewall. Each layer of the optical film has a limiting structure that can be accommodated within the first notch. The limiting structure is provided with a fixing part. At least two layers of the optical film include a first optical film disposed away from the light guide plate and a second optical film disposed close to the light guide plate. The limiting structure of the first optical film is provided with a hollow part. The orthographic projection of the hollow part on the second optical film is located within the fixing part of the second optical film, so as to expose the fixing part of the second optical film. The backlight module also includes a fixing tape for connecting to the fixing portion of each optical film to fix the at least two optical film layers. The fixing tape includes a first portion for bonding and fixing to the at least two optical film layers and a second portion for connecting to the side of the sidewall away from the light guide plate. The first part includes a first sub-part and a second sub-part arranged sequentially along a direction away from the second part. The length of the second sub-part in the first direction is greater than the length of the first notch in the first direction. The second sub-part and the first sub-part form a T-shaped structure. The first direction is parallel to the extension direction of the sidewall and perpendicular to the light emission direction of the light guide plate.

2. The backlight module according to claim 1, characterized in that, The fixing portions of each two adjacent layers of the optical film are staggered to form a stepped structure.

3. The backlight module according to claim 2, characterized in that, The second optical film material includes a first body, and a portion of at least one side of the first body extends outward to form the limiting structure. In a first direction, at least one side of the limiting structure of the second optical film material has a second notch at the connection point with the first body.

4. The backlight module according to claim 3, characterized in that, In a direction parallel to the second optical film, the cross-sectional shape of the second notch is semi-circular.

5. The backlight module according to claim 3, characterized in that, The first optical film includes a second body, and a portion of at least one side of the second body extends outward to form the limiting structure. In the first direction, at least one side of the limiting structure of the first optical film has a third notch at the connection between it and the second body.

6. The backlight module according to claim 5, characterized in that, In a direction parallel to the first optical film, the cross-sectional shape of the third notch is semi-circular.

7. The backlight module according to claim 5, characterized in that, In the first direction, the hollow portion is located in the middle of the limiting structure.

8. The backlight module according to claim 2, characterized in that, There is a seam between the first part and the second part.

9. The backlight module according to claim 1, characterized in that, The length of the first sub-part in the first direction is less than the length of the first notch in the first direction.

10. The backlight module according to claim 9, characterized in that, The length of the first sub-part in the first direction is the same as the length of the second part in the first direction.

11. The backlight module according to claim 1, characterized in that, The first notch is located at the middle of the sidewall along its extension direction.

12. A display device, characterized in that, Includes the backlight module as described in any one of claims 1-11.

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