Backlight module and display device

Abstract

The utility model relates to a backlight module and display device. A backlight module contains a backplate, a reflection sheet set up on the backplate, a light source set up on the reflection sheet, a light guide plate set up on the reflection sheet, a first positioning structure and at least one second positioning structure. The first positioning structure makes the backplate, the reflection sheet and the light guide plate unable to move along a first direction and a second direction, and the second direction is not parallel to the first direction. The second positioning structure is arranged on the same side as the first positioning structure and is spaced from the first positioning structure along the first direction. The second positioning structure is used to position the backplate, the reflection sheet and the light guide plate, so that the backplate, the reflection sheet and the light guide plate cannot move along the second direction, and the light guide plate has expansion and contraction allowance relative to the backplate and the reflection sheet along the first direction. The utility model also provides a display device containing the backlight module.

Description

Technical Field

[0001] This utility model relates to an optical device, and more particularly to a backlight module and display device that can enhance the positioning effect of internal components. Background Technology

[0002] Backlight modules installed on moving vehicles are continuously subjected to dynamic impacts such as road vibrations, sudden braking, and turning during operation. Furthermore, changes in high and low temperatures can cause deformation or expansion of internal components, or fatigue or hardening of the adhesive materials. Therefore, if the module's structure is not robust enough, internal components can easily become loose, deformed, or displaced. Existing positioning methods typically involve placing shock-absorbing elements in corners or bonding adjacent components with adhesive materials. However, these methods, even with prolonged use, do not completely solve the problem of scratches caused by internal component movement, resulting in white spots on the luminous surface and ultimately affecting display performance. Summary of the Invention

[0003] Therefore, the purpose of this utility model is to provide a backlight module that improves positioning accuracy and product stability.

[0004] A backlight module includes a backplate, a reflective sheet disposed on the backplate, a light source disposed on the reflective sheet, a light guide plate disposed on the reflective sheet for receiving light from the light source, a first positioning structure for fixing the backplate, the reflective sheet, and the light guide plate, and at least one second positioning structure. The light source extends along a first direction. The first positioning structure prevents the backplate, the reflective sheet, and the light guide plate from moving along the first direction and a second direction, wherein the second direction is not parallel to the first direction. The at least one second positioning structure is arranged on the same side as the first positioning structure and spaced apart from the first positioning structure along the first direction. The at least one second positioning structure is used to position the backplate, the reflective sheet, and the light guide plate, preventing the backplate, the reflective sheet, and the light guide plate from moving along the second direction, and providing the light guide plate with expansion and contraction allowance relative to the backplate and the reflective sheet along the first direction.

[0005] Another technical aspect of this utility model is that the first positioning structure and the at least one second positioning structure are located on the light-incident side of the light guide plate.

[0006] Another technical aspect of this utility model is that the first positioning structure and the at least one second positioning structure are respectively located at the two end positions of the light-incident side.

[0007] Another technical aspect of this utility model is that there are multiple second positioning structures, the first positioning structure is located at the center of the light-incident side, and the second positioning structures are located on both sides of the first positioning structure.

[0008] Another technical aspect of this utility model is that the light guide plate also includes two feet, which are respectively located at two corners near the first positioning structure and the second positioning structure, and protrude from the light-incident side.

[0009] Another technical aspect of this utility model is that the first positioning structure includes a first positioning groove recessed in the back plate, a first positioning hole passing through the reflector and corresponding in shape and position to the first positioning groove, and a first positioning post extending from the light guide plate to the back plate. The first positioning post passes through the first positioning hole and is inserted and positioned in the first positioning groove, and the first positioning post cannot move in either the first direction or the second direction.

[0010] Another technical aspect of this utility model is that the at least one second positioning structure includes a second positioning groove recessed in the back plate, a second positioning hole passing through the reflector and corresponding in shape and position to the second positioning groove, and a second positioning post extending from the light guide plate to the back plate. The second positioning post is inserted and positioned in the second positioning groove through the second positioning hole. The second positioning post is confined within the second positioning hole and the second positioning groove and cannot move in the second direction. The second positioning post can move relative to the second positioning hole and the second positioning groove along the first direction.

[0011] Another technical means of this utility model is that the second positioning hole and the second positioning groove have a first length in the first direction, and the second positioning post has a second length in the first direction, and the first length is greater than the second length.

[0012] Another technical aspect of this utility model is that the backlight module further includes at least one elastic member, which is disposed on the side of the light guide plate opposite to the light-incident side and is clamped between the light guide plate and the back plate.

[0013] Another technical means of this utility model is that the backlight module also includes an upper frame, which together with the back plate positions the light guide plate, wherein the upper frame covers the first positioning structure and the at least one second positioning structure in the thickness direction of the light guide plate.

[0014] Another objective of this invention is to provide a display device comprising a backlight module as described above, and a display panel disposed on the backlight module.

[0015] The advantage of this invention lies in the fact that, through the combination of the first positioning structure and the second positioning structure, the back plate and the reflector cannot move in either the first or second direction, and the light guide plate cannot move in the second direction, but has room for expansion and contraction relative to the back plate and the reflector in the first direction. This improves the positioning stability of the overall structure while preserving the elastic space for expansion and contraction of the light guide plate. Attached Figure Description

[0016] Figure 1 This is a top view schematic diagram, which is a preferred embodiment of the backlight module of this utility model; Figure 2 This is a side view schematic diagram illustrating the internal structure of the preferred embodiment; Figure 3 This is a side view schematic diagram illustrating the configuration of the preferred embodiment having multiple second positioning structures; Figure 4 It is a partial three-dimensional sectional view, used to illustrate the first positioning structure; Figure 5 It is a partial three-dimensional sectional view, used to illustrate a second positioning structure; and Figure 6 This is a side view schematic diagram, which is a preferred embodiment of the display device of this utility model. Detailed Implementation

[0017] The features and technical content of this utility model will be clearly presented in the following detailed description of the preferred embodiments with reference to the accompanying drawings. Before the detailed description, it should be noted that similar elements are represented by the same numbers. The directional terms mentioned in the following embodiments, such as up, down, left, right, front, back, bottom, and top, are only for reference to the accompanying drawings. Therefore, the directional terms used are for illustrative purposes and not for limiting the utility model.

[0018] See Figure 1 and Figure 2 This is a preferred embodiment of the backlight module 2 of the present invention, comprising a backplate 21, a reflective sheet 22 disposed on the backplate 21, a light source 23 disposed on the reflective sheet 22, a light guide plate 24 disposed on the reflective sheet 22 for receiving light from the light source 23, a first positioning structure P1 for fixing the backplate 21, the reflective sheet 22, and the light guide plate 24, and at least one second positioning structure P2. The light source 23 extends along a first direction D1. The first positioning structure P1 prevents the backplate 21, the reflective sheet 22, and the light guide plate 24 from moving along the first direction D1 and a second direction D2, wherein the second direction D2 is not parallel to the first direction D1. The at least one second positioning structure P2 is arranged on the same side as the first positioning structure P1 and spaced apart from the first positioning structure P1 along the first direction D1. The at least one second positioning structure P2 is used to position the back plate 21, the reflector 22, and the light guide plate 24, preventing the back plate 21, the reflector 22, and the light guide plate 24 from moving along the second direction D2. The light guide plate 24 has expansion and contraction allowance relative to the back plate 21 and the reflector 22 along the first direction D1. It should be noted that, for the sake of simplicity, ... Figure 1The components located above the light guide plate 24 are omitted and not shown.

[0019] By combining the first positioning structure P1 and the second positioning structure P2, the back plate 21 and the reflector 22 are immobile in both the first direction D1 (X-axis) and the second direction D2 (Y-axis), while the light guide plate 24 is immobile in the second direction D2. However, it has expansion and contraction margins relative to the back plate 21 and the reflector 22 in the first direction D1, allowing the light guide plate 24 to move only in a specific direction during thermal expansion and contraction. This improves the overall structural positioning stability and preserves the elasticity of the light guide plate 24 during expansion and contraction. Especially considering that the backlight module 2 of this invention is used in an automotive environment where temperature changes are drastic, it is even more necessary to reserve space for thermal expansion and contraction.

[0020] More specifically, such as Figure 1 and Figure 2 As shown, in this embodiment, there is one second positioning structure P2. Both the first positioning structure P1 and the second positioning structure P2 are located near the light-incident side 240 of the light guide plate 24, and are respectively located at both ends of the light source 23. In this way, after the backlight module 2 has been used for a period of time, the light source 23 heats up, causing localized thermal expansion of the light-incident side 240 of the light guide plate 24. The combination of the first positioning structure P1 and the second positioning structure P2 ensures that the light guide plate 24 can only move in a specific direction during thermal expansion and contraction. This improves the overall positioning stability of the structure while preserving the elastic space for expansion and contraction of the light guide plate 24. In some embodiments, if the backlight module 2 is large, two or more second positioning structures P2 can be provided on the light guide plate 24 to ensure the positioning effect. Figure 3 As shown, when multiple second positioning structures P2 are provided, one first positioning structure P1 and one second positioning structure P2 are respectively located at the two ends of the light-incident side 240, and the remaining second positioning structures P2 are distributed in the middle position of the light guide plate 24. In other embodiments, the first positioning structure P1 may be located in the center of the light-incident side 240, and the second positioning structures P2 may be located on both sides of the first positioning structure P1. In this way, when the light guide plate 24 expands and contracts due to heat, the volume change of its expansion and contraction can be distributed on both sides of the first positioning structure P1, reducing the amount of volume change on the same side.

[0021] More specifically, such as Figure 2 and Figure 4As shown, the first positioning structure P1 includes a first positioning groove 211 recessed in the back plate 21, a first positioning hole 221 passing through the reflector 22 and corresponding in shape and position to the first positioning groove 211, and a first positioning post 241 extending from the light guide plate 24 towards the back plate 21. The first positioning post 241 is inserted and positioned within the first positioning groove 211 through the first positioning hole 221. That is, as Figure 1 As shown, the first positioning post 241 is similar in shape to the first positioning hole 221 and the first positioning groove 211, leaving only an assembly gap to facilitate assembly. However, the first positioning post 241 cannot move in either the first direction D1 or the second direction D2, ensuring that the light guide plate 24 cannot move in either direction D1 or the second direction D2. It should also be noted that the backlight module 2 includes multiple elastic members 25, which are located on the side of the light guide plate 24 opposite to the light-incident side 240 and are clamped between the light guide plate 24 and the back plate 21. The light guide plate 24 has feet 243 protruding from the light-incident side 240 at two corners near the first positioning structure P1 and the second positioning structure P2, thereby creating a fixed distance between the light source 23 and the light guide plate 24. Figure 1 In terms of orientation, the elastic member 25 abuts against the top of the light guide plate 24, and the first positioning structure P1 is located below the light guide plate 24, thus limiting the light guide plate 24 both above and below in the second direction D2 (Y-axis), preventing it from moving in that direction. This ensures that the distance between the light-incident side 240 of the light guide plate 24 and the light source 23 remains fixed and does not change due to the expansion or contraction of the light guide plate 24, thereby avoiding any impact on optical brightness.

[0022] See also Figure 2 and Figure 5 Each of the second positioning structures P2 includes a second positioning groove 212 recessed in the back plate 21, a second positioning hole 222 passing through the reflector 22 and corresponding in shape and position to the second positioning groove 212, and a second positioning post 242 extending from the light guide plate 24 to the back plate 21. Figure 2 As shown, the second positioning hole 222 and the second positioning groove 212 have a first length L1 in the first direction D1, and the second positioning post 242 has a second length L2 in the first direction D1. The first length L1 is greater than the second length L2. More specifically, as... Figure 1 and Figure 2As shown, in this embodiment, the second positioning hole 222 and the second positioning groove 212 extend along the first direction D1 and are elongated elliptical in shape. However, the second positioning hole 222 and the second positioning groove 212 only retain an assembly gap compared to the second positioning post 242 in the second direction D2. Therefore, when the second positioning post 242 passes through the second positioning hole 222 and is inserted and positioned in the second positioning groove 212, the second positioning post 242 is confined within the second positioning hole 222 and the second positioning groove 212 and cannot move in the second direction D2. However, through the structural design that the first length L1 is greater than the second length L2, the second positioning post 242 can move relative to the second positioning hole 222 and the second positioning groove 212 along the first direction D1. In other words, the side of the light guide plate 24 closest to the first positioning structure P1 is fixed. When the light guide plate 24 undergoes volume changes due to thermal expansion and contraction, the light guide plate 24 can only use the first positioning structure P1 as a reference point, so that the second positioning post 242 of the light guide plate 24 can move along the first direction D1 in the second positioning groove 212. More specifically, in this embodiment, the at least one second positioning structure P2 and the first positioning structure P1 are arranged at intervals along the long side of the light guide plate 24. The first positioning structure P1 serves as a positioning point, and the space between the second positioning hole 222 and the second positioning groove 212 of the at least one second positioning structure P2 is used to accommodate the expansion and contraction of the long side of the light guide plate 24 caused by the heat from the light source 23. On the other hand, there are two elastic members 25. One elastic member 25 is arranged at intervals along the short side of the light guide plate 24 and the first positioning structure P1, while the other elastic member 25 is arranged at intervals along the short side of the light guide plate 24 and the at least one second positioning structure P2. The feet 243 of the light guide plate 24 are used to position the short side of the light guide plate 24. The expansion and contraction of the short side of the light guide plate 24 is absorbed by the elasticity of the elastic member 25.

[0023] See Figure 4 and Figure 5 The backlight module 2 also includes an upper frame 26 that, together with the back plate 21, positions the light guide plate 24. The upper frame 26 covers the first positioning structure P1 and the second positioning structure P2 in the thickness direction of the light guide plate 24. This ensures that the first positioning structure P1 and the second positioning structure P2 do not negatively affect the optical effect of the light guide plate 24, maintaining the overall optical quality. Figure 6 The diagram shows a preferred embodiment of the display device of this invention, comprising a backlight module 2 and a display panel 3 disposed on the backlight module 2. The backlight module 2 of this invention can be widely used in automotive display devices, improving upon the defects of the light guide plate 24 caused by high and low temperatures and vibration, thus meeting the stringent testing requirements of the automotive market.

[0024] This invention, through the combination of the first positioning structure P1 and the second positioning structure P2, ensures that the back plate 21 and the reflector 22 are immobile in both the first direction D1 and the second direction D2, while the light guide plate 24 is immobile in the second direction D2. However, it has expansion and contraction margins relative to the back plate 21 and the reflector 22 in the first direction D1. This improves the positioning stability of the light guide plate 24 while retaining expansion and contraction elasticity. Simultaneously, the snap-fit ​​connection reduces the need for adhesive tape, lowering material costs and assembly time. Furthermore, this design ensures a fixed distance between the light guide plate 24 and the light source 23, while mitigating displacement or scratches caused by high or low temperatures or vibration, thus improving the overall yield of the light-emitting surface and reducing product maintenance costs.

[0025] However, the above description is only a preferred embodiment of the present utility model and should not be construed as limiting the scope of the present utility model. All simple equivalent changes and modifications made in accordance with the scope of the present utility model patent application and the description of the utility model shall still fall within the scope of the present utility model patent.

[0026] [Symbol Explanation] 2 backlight modules 21 back panel 211 First positioning slot 212 Second positioning slot 22 reflective sheet 221 First positioning hole 222 Second positioning hole 23 light sources 24 light guide plates 240 incident light side 241 First Positioning Post 242 Second Positioning Post 243 feet 25 elastic elements 26 top frame 3 Display Panels D1 First Direction D2 Second Direction L1 First Length L2 second length P1 First Positioning Structure P2 is the second positioning structure.

Claims

1. A backlight module, characterized in that, Include: Back panel; A reflective sheet is disposed on the back plate; A light source is disposed on the reflector and extends along the first direction; A light guide plate is disposed on the reflector and used to receive the light from the light source; The first positioning structure is used to fix the back plate, the reflective sheet, and the light guide plate so that the back plate, the reflective sheet, and the light guide plate cannot move along the first direction and the second direction, and the second direction is not parallel to the first direction. and At least one second positioning structure is arranged on the same side as the first positioning structure and spaced apart from the first positioning structure along the first direction. The at least one second positioning structure is used to position the back plate, the reflective sheet, and the light guide plate so that the back plate, the reflective sheet, and the light guide plate cannot move along the second direction, and the light guide plate has expansion and contraction allowance relative to the back plate and the reflective sheet along the first direction.

2. The backlight module as described in claim 1, characterized in that, The first positioning structure and the at least one second positioning structure are located on the light-incident side of the light guide plate.

3. The backlight module as described in claim 2, characterized in that, The first positioning structure and the at least one second positioning structure are located at the two end positions of the light-incident side, respectively.

4. The backlight module as described in claim 2, characterized in that, The second positioning structure is multiple, with the first positioning structure located at the center of the light-incident side and the second positioning structures located on both sides of the first positioning structure.

5. The backlight module as described in claim 2, characterized in that, The light guide plate also includes two feet, which are respectively located at two corners near the first positioning structure and the second positioning structure, and protrude from the light-incident side.

6. The backlight module as described in claim 2, characterized in that, It also includes at least one elastic member disposed on the side of the light guide plate opposite to the light incident side and clamped between the light guide plate and the back plate.

7. The backlight module as described in claim 1, characterized in that, The first positioning structure includes a first positioning groove recessed in the back plate, a first positioning hole passing through the reflector and corresponding in shape and position to the first positioning groove, and a first positioning post extending from the light guide plate to the back plate. The first positioning post passes through the first positioning hole and is inserted into the first positioning groove, and the first positioning post cannot move in either the first direction or the second direction.

8. The backlight module as described in claim 1, characterized in that, The at least one second positioning structure includes a second positioning groove recessed in the back plate, a second positioning hole passing through the reflector and corresponding in shape and position to the second positioning groove, and a second positioning post extending from the light guide plate to the back plate. The second positioning post passes through the second positioning hole and is inserted and positioned in the second positioning groove. The second positioning post is confined within the second positioning hole and the second positioning groove and cannot move in the second direction. The second positioning post can move relative to the second positioning hole and the second positioning groove in the first direction.

9. The backlight module as described in claim 8, characterized in that, The second positioning hole and the second positioning groove have a first length in the first direction, and the second positioning post has a second length in the first direction, the first length being greater than the second length.

10. The backlight module as described in claim 1, characterized in that, It also includes a top frame that, together with the back plate, positions the light guide plate, wherein the top frame covers the first positioning structure and the at least one second positioning structure in the thickness direction of the light guide plate.

11. A display device, characterized in that, It includes a backlight module as described in any one of claims 1 to 10, and a display panel disposed on the backlight module.

Images