Backlight module and display device

Abstract

The present invention relates to the field of display, and discloses a backlight module and a display device, wherein the backlight module comprises: a back plate, the back plate comprises a bottom plate and a side plate connected to the bottom plate, the bottom plate and the side plate form a receiving space; a frame located in the receiving space, the frame is close to the side plate and connected to the side plate, and a first clamping portion is formed on a surface of the frame away from the side plate; a light guide plate located in the receiving space, the light guide plate is arranged on the bottom plate; an optical film layer located on a side of the light guide plate away from the bottom plate, the optical film layer comprises a multi-layer stacked optical film, at least one layer of the multi-layer stacked optical film comprises a main body and an extension portion located at the periphery of the main body, the orthographic projection of the main body on the light guide plate is located in the light guide plate, and a second clamping portion corresponding to the first clamping portion is arranged on the extension portion, so that the first clamping portion is clamped with the second clamping portion. The optical film layer in the backlight module is fixed to the frame more firmly, and the optical film layer is not prone to wrinkles.

Description

Technical Field

[0001] The present invention relates to the technical field of display, and in particular to a backlight module and a display device. Background Art

[0002] Liquid crystal display (LCD) mainly includes a liquid crystal display panel and a backlight module. The light source in the backlight module can be mainly divided into LED (Light Emitting Diode, LED for short) backlight source and CCFL (Cold Cathode Fluorescent Lamp, CCFL for short) backlight source according to the type of light source.

[0003] The display panel and the backlight source are assembled as a whole through the back cover and the frame. However, when the liquid crystal display device is tested in a high temperature and high humidity environment, the optical film layer in the backlight module is constrained and cannot expand along the gap between the frame. The expansion will be concentrated at the edge of the display screen and irreversible wavy wrinkles will occur. Summary of the invention

[0004] The invention discloses a backlight module and a display device, which are used to fix an optical film layer and a frame in the backlight module more firmly, and the optical film layer is not prone to wrinkles.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a backlight module, comprising:

[0007] A back plate, the back plate comprising a bottom plate and side plates connected to the bottom plate, the bottom plate and the side plates forming a receiving space;

[0008] a frame located in the accommodating space, the frame being close to the side plate and connected to the side plate, and a first clamping portion being formed on a side surface of the frame away from the side plate;

[0009] A light guide plate located in the accommodation space, wherein the light guide plate is arranged on the bottom plate;

[0010] The optical film layer is located on the side of the light guide plate away from the bottom plate, the optical film layer includes a plurality of optical films stacked together, at least one layer of the plurality of optical films stacked together includes a main body and an extension portion located outside the main body, the main body is located within the light guide plate in its orthographic projection, and a second clamping portion corresponding to the first clamping portion is provided on the extension portion, so that the first clamping portion is clamped with the second clamping portion.

[0011] The bottom plate and the side plate in the back plate of the backlight module provided by the present invention form a accommodating space, the frame, the light guide plate and the optical film layer are all located in the accommodating space, the frame is connected to the side plate, and a first clamping portion is formed on the surface of the frame away from the side plate; the light guide plate is arranged on the bottom plate; the optical film layer is located on the side of the light guide plate away from the bottom plate, specifically, the optical film layer includes a plurality of optical films stacked in layers, at least one layer of the optical film in the plurality of layers includes a main body and an extension portion located at the periphery of the main body, the orthographic projection of the main body on the light guide plate is located in the light guide plate, a second clamping portion corresponding to the first clamping portion is arranged on the extension portion, and the first clamping portion is clamped with the second clamping portion to fix the position of the optical film layer relative to the frame, because at least one side of the optical film layer is relatively fixed to the frame, a relative tension is generated between the two, thereby effectively ensuring that when the liquid crystal display device is tested in a high temperature and high humidity environment, the optical film layer expands along the gap between the frame, so that the expansion amount will not accumulate, effectively avoiding the occurrence of irreversible wavy wrinkles, thereby ensuring the display effect.

[0012] Optionally, the main body is parallel to the plane where the bottom plate is located, and the extension portion is bent toward the bottom plate.

[0013] Optionally, the first clamping portion and the frame are an integrated structure.

[0014] Optionally, the first clamping portion includes a plurality of protrusions; the second clamping portion includes a plurality of openings;

[0015] The protrusion extends into the opening for locking.

[0016] Optionally, the protrusions correspond to the openings one by one;

[0017] The protruding direction of the protrusion is not perpendicular to the plane where the protrusion is located on the frame.

[0018] Optionally, the optical film layer includes: a first diffuser, a first brightness enhancement sheet, a second brightness enhancement sheet and a second diffuser which are stacked; the first diffuser has a main body and an extension portion located at the periphery of the main body, and the second clamping portion is arranged on the extension portion of the first diffuser.

[0019] Optionally, the frame includes a side wall arranged around the inner side of the side plate, and the inner side of the side wall has a step portion;

[0020] The first clamping portion is located on a side of the step portion facing the bottom plate.

[0021] In a second aspect, the present invention provides a display device, comprising the backlight module described in any one of the first aspects and a display panel located at the light emitting side of the backlight module; the display panel is located in the accommodating space and fixed on the frame.

[0022] Optionally, the display device further includes: a light-shielding tape layer, wherein the light-shielding tape layer is located between the backlight module and the display panel, and between the display panel and the frame.

[0023] Optionally, the light-shielding tape layer includes an adhesive area and an adhesive-free area;

[0024] The adhesive area is located between the optical film layer and the display panel; and the adhesive-free area is located between the frame and the display panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of the effect of wrinkling of a display device in the prior art;

[0026] Figure 2 A schematic structural diagram of a first clamping portion in a backlight module provided by an embodiment of the present invention;

[0027] Figure 3 A schematic diagram of the structure of the cooperation between the first clamping portion and the second clamping portion in a backlight module provided by an embodiment of the present invention;

[0028] Figure 4 A schematic diagram of the planar structure of an optical film layer in a backlight module provided by an embodiment of the present invention;

[0029] Figure 5 for Figure 4 A schematic diagram of the enlarged local structure of the A area in the middle;

[0030] Figure 6 A schematic diagram of the structure of a display device provided by an embodiment of the present invention;

[0031] Figure 7 for Figure 6 Schematic diagram of the enlarged local structure of area B in FIG.

[0032] Icons: 1-back plate; 11-bottom plate; 12-side plate; 2-frame; 21-first clamping part; 22-side wall; 23-step part; 3-light guide plate; 4-optical film layer; 41-first diffuser; 411-main body; 412-extension part; 413-pre-folding line; 4121-second clamping part; 42-first brightness enhancement film; 43-second brightness enhancement film; 44-second diffuser; 5-display panel; 51-color film substrate; 52-array substrate; 53-upper polarizer; 54-lower polarizer; 6-light-shielding tape layer; 61-adhesive area; 611-adhesive layer; 62-no-adhesive area; 7-reflector. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] like Figure 1 As shown, the display panel 5 and the backlight source are assembled as a whole through the back cover 1 and the frame 2. However, when the liquid crystal display device is tested in a high temperature and high humidity environment, the optical film layer 4 in the backlight module is constrained and cannot expand along the gap between the frame 2. The expansion will be concentrated at the edge of the display screen and irreversible wavy wrinkles will occur.

[0035] In order to ensure the display effect of the display device and reduce the probability of wrinkles in the optical film layer 4 in the display panel 5, the following improvements are made to the display device:

[0036] like Figure 2 and Figure 3 As shown, an embodiment of the present invention provides a backlight module, including:

[0037] A back plate 1, the back plate 1 comprises a bottom plate 11 and a side plate 12 connected to the bottom plate 11, the bottom plate 11 and the side plate 12 forming a receiving space;

[0038] A frame 2 is located in the accommodating space, the frame 2 is close to the side plate 12 and connected to the side plate 12, and a first clamping portion 21 is formed on a side surface of the frame 2 away from the side plate 12;

[0039] A light guide plate 3 located in the accommodation space, wherein the light guide plate 3 is arranged on the bottom plate 11;

[0040] The optical film layer 4 is located on the side of the light guide plate 3 away from the bottom plate 11, and the optical film layer 4 includes a multi-layer stacked optical film. At least one layer of the multi-layer stacked optical film includes a main body 411 and an extension portion 412 located at the periphery of the main body 411. The orthographic projection of the main body 411 on the light guide plate 3 is located inside the light guide plate 3. The extension portion 412 is provided with a second clamping portion 4121 corresponding to the first clamping portion 21, so that the first clamping portion 21 is clamped with the second clamping portion 4121.

[0041] It should be noted that the bottom plate 11 and the side plate 12 in the back plate 1 of the backlight module provided by the present invention form a storage space, the frame 2, the light guide plate 3 and the optical film layer 4 are all located in the storage space, the frame 2 is connected to the side plate 12, and a first clamping portion 21 is formed on the surface of the frame 2 on the side away from the side plate 12; the light guide plate 3 is arranged on the bottom plate 11; the optical film layer 4 is located on the side of the light guide plate 3 away from the bottom plate 11, specifically, the optical film layer 4 includes a plurality of optical films stacked together, at least one optical film in the multi-layer optical film includes a main body 411 and an extension portion 412 located on the periphery of the main body 411, the main body 411 is on the light guide plate 3 The orthographic projection is located in the light guide plate 3, and a second clamping portion 4121 corresponding to the first clamping portion 21 is provided on the extension portion 412, and the first clamping portion 21 is clamped with the second clamping portion 4121 to relatively fix the position of the optical film layer 4 and the frame 2. Since at least one side of the optical film in the optical film layer 4 is relatively fixed to the frame 2, a relative tension is generated between the two, thereby effectively ensuring that when the liquid crystal display device is tested in a high temperature and high humidity environment, the optical film layer 4 expands along the gap between the frame 2, so that the expansion amount will not accumulate, effectively avoiding the occurrence of irreversible wavy wrinkles, thereby ensuring the display effect.

[0042] like Figure 4 and Figure 5 As shown, the main body 411 and the extension 412 are separated by a pre-folding line 413 to facilitate the bending of the extension 412 in a direction perpendicular to the bottom plate 11. The pre-folding line 413 is provided to facilitate the bending of the extension 412, and when the extension 412 is bent relative to the main body 411, the edge is more neat and the force is more evenly applied, thereby preventing the generation of local stress, so that the bending position between the main body 411 and the bending portion generates local stress and the strength becomes lower.

[0043] like Figure 2 and Figure 3 The main body 411 is parallel to the plane where the base plate 11 is located, and the extension portion 412 is bent toward the base plate 11; for example, the bending direction of the extension portion 412 can also be bent away from the base plate 11, and the specific bending direction of the extension portion 412 is related to the structure of the first clamping portion 21.

[0044] In a possible embodiment, the first clamping portion 21 and the frame 2 are an integrated structure, and specifically, the frame 2 having the first clamping portion 21 may be formed by injection molding.

[0045] The first clamping portion 21 specifically includes a plurality of protrusions; the second clamping portion 4121 includes a plurality of openings; the protrusions extend into the openings for clamping.

[0046] For example, the protrusions and the openings may correspond one to one, that is, one protrusion corresponds to one opening, forming a one to one corresponding snap-fit ​​structure to relatively fix the frame 2 and the optical film layer 4. Of course, at least two protrusions may be snap-fitted to one opening, for example, two protrusions may form a corresponding snap-fit ​​structure with one opening, or three protrusions may form a corresponding snap-fit ​​structure with one opening, as long as the protrusions and the openings cooperate to form a snap-fit ​​structure, and of course the specific number of openings and protrusions may be selected according to the size of the backlight module provided in the embodiment of the present invention.

[0047] In order to ensure that the optical film layer 4 and the frame 2 are relatively fixed and to ensure that a relative tension is generated between the two, a first clamping portion 21 is provided on at least one side of the four sides of the frame 2, and a second clamping portion 4121 is provided on at least one side of the sky side, the ground side, the left side, and the right side of the optical film layer 4. Of course, in order to ensure that the optical film layer 4 and the frame 2 are relatively fixed more firmly and to ensure that a sufficient relative tension is generated between the two, a first clamping portion 21 is provided on all four sides of the frame 2, and a second clamping portion 4121 is provided on the sky side, the ground side, the left side, and the right side of the optical film layer 4, so that sufficient relative tension is generated between the optical film layer 4 and the frame 2 in four directions.

[0048] The first clamping portion 21 in a backlight module provided by an embodiment of the present invention specifically includes a plurality of protrusions; the second clamping portion 4121 includes a plurality of openings; and the protrusions extend into the openings for clamping.

[0049] Specifically, the protruding direction of the protrusion is not perpendicular to the plane where the protrusion is located on the frame 2. For example, the protrusion structure can be a cone, a cube, etc. In order to facilitate the protrusion to extend into the opening and form a relative tension between the optical film layer 4 and the frame 2, the extended direction of the axis of the protrusion is not perpendicular to the inner side of the frame 2. Figure 3 Since the protrusion is bent toward the bottom plate 11, the extension portion 412 on the optical film layer 4 is bent toward the bottom plate 11, and the opening of the extension portion 412 forms a tensioning force with the protrusion.

[0050] The optical film layer 4 comprises: a first diffuser 41, a first brightness enhancement sheet 42, a second brightness enhancement sheet 43 and a second diffuser 44 which are stacked; the first diffuser 41 has a main body 411 and an extension 412 located outside the main body 411, and the second clamping portion 4121 is disposed on the extension 412 of the first diffuser 41. Figure 3, the protrusion is bent toward the bottom plate 11, and the extension portion 412 of the first diffuser 41 in the optical film layer 4 is bent toward the bottom plate 11, and the opening of the extension portion 412 and the protrusion form a tensioning force; for example, the extension portion 412 can also be on the first brightness enhancement sheet 42 in the optical film layer 4, and similarly, as long as the opening of the extension portion 412 and the protrusion form a tensioning force; for example, the extension portion 412 can also be on the second brightness enhancement sheet 43 in the optical film layer 4, and similarly, as long as the opening of the extension portion 412 and the protrusion form a tensioning force; for example, the extension portion 412 can also be on the second diffuser 44 in the optical film layer 4, and similarly, as long as the opening of the extension portion 412 and the protrusion form a tensioning force.

[0051] The first diffuser 41 , the second diffuser 44 , the first brightness enhancement sheet 42 , and the second brightness enhancement sheet 43 in the optical film layer 4 play a role in diffusing and gathering light.

[0052] Of course, the bending direction of the extension part 412 is related to the position of the optical film in the optical film layer 4 and the bending direction of the protrusion. That is to say, when the protrusion is bent toward the bottom plate 11, and the extension part 412 is located on the first diffuser 41 in the optical film layer 4, the extension part 412 is bent toward the bottom plate 11 so that the protrusion and the opening on the extension part 412 can be clamped to form a tension force; when the protrusion is bent in the direction away from the bottom plate 11, and the extension part 412 is located on the second brightness enhancement sheet 43 in the optical film layer 4, the extension part 412 is set to be bent in the direction away from the bottom plate 11 so that the protrusion and the opening on the extension part 412 can be clamped to form a tension force. Of course, the above is only an example. There are many other settings for the protrusion and the extension part 412, which will not be repeated one by one. As long as the protrusion and the opening on the extension part 412 can be clamped to form a tension force, it is within the scope defined by the present invention.

[0053] Optionally, the frame 2 includes a side wall 22 disposed around the inner side of the side plate 12, and the inner side of the side wall 22 has a step portion 23;

[0054] The first clamping portion 21 is located on a side of the step portion 23 facing the bottom plate 11 .

[0055] Since the step portion 23 protrudes toward the accommodating cavity, that is, the gap between the step portion 23 and the optical film layer 4 is smaller than the gap between the side wall 22 and the optical film layer 4, setting the first clamping portion 21 on the inner side of the step portion 23 will save more material of the extension portion 412 and the tensioning force will also be greater.

[0056] The backlight module provided in the embodiment of the present invention further includes a reflective sheet 7 arranged between the light guide plate 3 and the optical film layer 4 .

[0057] In a second aspect, an embodiment of this aspect provides a display device, comprising the backlight module of any one of the first aspect and a display panel 5 located at the light emitting side of the backlight module; the display panel 5 is located in the accommodating space and fixed on the frame 2.

[0058] Optionally, the display device further includes: a light shielding tape layer 6, which is located between the backlight module and the display panel 5, and between the display panel 5 and the frame 2. Specifically, the light shielding tape layer 6 not only fixes the optical film layer 4, but also blocks light leaking from the edge of the display panel 5.

[0059] When the shading tape layer 6 is adhered to the backlight module and the display panel 5, and between the display panel 5 and the frame 2, when the liquid crystal display device is tested in a high temperature and high humidity environment, the optical film layer 4 in the backlight module and the display panel 5 are bound by the shading tape layer 6. Therefore, the optical film layer 4 cannot expand along the gap between the frame 2, and the expansion will be concentrated at the edge of the display screen, and irreversible wavy wrinkles will occur.

[0060] Therefore, the light shielding tape layer 6 is improved as follows. The light shielding tape layer 6 specifically includes a glue area 61 and a glue-free area 62;

[0061] The adhesive area 61 is located between the optical film layer 4 and the display panel 5, and the non-adhesive area 62 is located between the frame 2 and the display panel 5. Of course, an adhesive layer 611 is provided on the light shielding tape layer in the adhesive area, while no adhesive layer is provided on the light shielding tape layer in the non-adhesive area.

[0062] Since there is a glue-free area 62 of the light-shielding tape layer 6 between the frame 2 and the display panel 5, the optical film layer 4 is prone to detachment from the light-shielding tape layer 6 during transportation and turnover of the liquid crystal display device. That is, the topmost first diffuser 41 in the optical film layer 4 breaks away from the constraints of the glue-free area 62 of the light-shielding tape layer 6 and runs onto the light-shielding tape layer 6. Local structural extrusion will cause serious local black shadow problems.

[0063] In order to prevent the problem of jumping off, a first clamping portion 21 is formed on the surface of one side of the frame 2 away from the side plate 12; the optical film layer 4 includes a plurality of optical films stacked together, and at least one layer of the optical film in the multi-layer optical film includes a main body 411 and an extension portion 412 located on the periphery of the main body 411, and the orthographic projection of the main body 411 on the light guide plate 3 is located inside the light guide plate 3, and a second clamping portion 4121 corresponding to the first clamping portion 21 is arranged on the extension portion 412, and the first clamping portion 21 is clamped with the second clamping portion 4121 to fix the position of the optical film layer 4 and the frame 2 relatively. Since at least one side of the optical film layer 4 is relatively fixed to the frame 2, a relative tension is generated between the two, thereby effectively ensuring that when the liquid crystal display device is tested in a high temperature and high humidity environment, the optical film layer 4 expands along the gap between it and the frame 2, so that the expansion amount will not accumulate, effectively avoiding the occurrence of irreversible wavy wrinkles, thereby ensuring the display effect.

[0064] Specifically, when the display panel 5 is a liquid crystal display panel 5, Figure 6 And refer to Figure 7 As shown, the liquid crystal display panel 5 includes an array substrate 52 and a color filter substrate 51, and a liquid crystal layer (not shown in the figure) located between the array substrate 52 and the color filter substrate 51, and the liquid crystal display panel 5 also includes an upper polarizer 53 arranged at the top end of the color filter substrate 51, and a lower polarizer 54 arranged at the bottom end of the array substrate 52.

[0065] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A backlight module, characterized in that: include: A back plate, the back plate comprising a bottom plate and side plates connected to the bottom plate, the bottom plate and the side plates forming a receiving space; a frame located in the accommodating space, the frame being close to the side plate and connected to the side plate, and a first clamping portion being formed on a side surface of the frame away from the side plate; A light guide plate located in the accommodation space, wherein the light guide plate is arranged on the bottom plate; an optical film layer located on a side of the light guide plate away from the bottom plate, the optical film layer comprising a plurality of optical films stacked together, at least one layer of the optical films in the plurality of optical films stacked together comprising a main body and an extension located outside the main body, the main body being located within the light guide plate in an orthographic projection thereof, and a second clamping portion corresponding to the first clamping portion being disposed on the extension portion, so that the first clamping portion is clamped with the second clamping portion; The light-shielding tape layer includes a glue area and a non-glue area; the light-shielding tape layer in the glue area is provided with an adhesive layer and is bonded to the frame; the light-shielding tape layer in the non-glue area is not provided with an adhesive layer and is placed on the surface of the optical film layer on the side away from the base plate.

2. The backlight module according to claim 1, characterized in that: The main body is parallel to the plane where the bottom plate is located, and the extension portion is bent toward the bottom plate.

3. The backlight module according to claim 1, characterized in that: The first clamping portion and the frame are an integrated structure.

4. The backlight module according to claim 2, characterized in that: The first clamping portion includes a plurality of protrusions; the second clamping portion includes a plurality of openings; The protrusion extends into the opening for locking.

5. The backlight module according to claim 4, characterized in that: The protrusions correspond to the openings one by one; The protruding direction of the protrusion is not perpendicular to the plane where the protrusion is located on the frame.

6. The backlight module according to any one of claims 1 to 5, characterized in that: The optical film layer comprises: a first diffuser, a first brightness enhancement sheet, a second brightness enhancement sheet and a second diffuser which are stacked; the first diffuser has a main body and an extension portion located at the periphery of the main body, and the second clamping portion is arranged on the extension portion of the first diffuser.

7. The backlight module according to any one of claims 1 to 5, characterized in that: The frame includes a side wall arranged around the inner side of the side plate, and the inner side of the side wall has a step portion; The first clamping portion is located on a side of the step portion facing the bottom plate.

8. A display device, characterized in that: It comprises the backlight module according to any one of claims 1 to 7 and a display panel located at the light-emitting side of the backlight module; the display panel is located in the accommodating space and fixed on the frame.

9. The display device according to claim 8, characterized in that: The display device further includes: a light shielding tape layer, wherein the light shielding tape layer is located between the backlight module and the display panel, and between the display panel and the frame.

10. The display device according to claim 9, characterized in that: The light-shielding tape layer includes an adhesive area and an adhesive-free area; The adhesive area is located between the optical film layer and the display panel; and the adhesive-free area is located between the frame and the display panel.

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