Gel frame, backlight module and display device

Abstract

This application provides a frame, a backlight module, and a display device. By providing a support portion in the first recess of the frame for accommodating a flexible printed circuit board, the support portion supports the flexible printed circuit board when it is subjected to tension during assembly onto the backlight module, preventing excessive stretching of the flexible printed circuit board. Force is applied to the liquid crystal display panel through the end of the flexible printed circuit board bonded to it, causing localized changes in the cell thickness of the liquid crystal display panel. This results in uneven brightness in certain areas when the display device is used, thereby improving the user's visual experience.

Description

Technical Field

[0001] This application relates to the field of display technology, and more particularly to a frame, a backlight module, and a display device. Background Technology

[0002] Currently, automotive display devices typically use a flexible printed circuit board (PCB) to be thermo-bonded onto the thin-film transistor array (TFT-LCD) substrate of a liquid crystal display (LCD) panel. The LCD panel with the PCB bonded to it is then assembled onto the backlight module's frame using adhesive tape. When the PCB is placed in the recessed groove of the frame and bent to the back of the backlight module, the end of the PCB fixed to the TFT-LCD substrate experiences stress during assembly. This stress is applied to the TFT-LCD substrate, causing a change in the cell thickness at the location where the PCB is bonded to the LCD panel. This results in uneven brightness when light passes through the LCD panel, a phenomenon known as the Mura effect.

[0003] Therefore, it is necessary to propose a technical solution to address the problem of uneven brightness in the LCD panel caused by the assembly of flexible printed circuit boards onto the backlight module frame. Summary of the Invention

[0004] The purpose of this application is to provide a frame, a backlight module, and a display device to solve the problem of uneven brightness in the liquid crystal display panel when the flexible printed circuit board is assembled on the frame of the backlight module.

[0005] To achieve the above objectives, the technical solution is as follows.

[0006] A display device includes a liquid crystal display panel, a flexible printed circuit board, and a backlight module. The backlight module includes a frame having a first supporting surface, a second supporting surface protruding from the first supporting surface, and a first recess formed between the first supporting surface and the second supporting surface. The liquid crystal display panel is fixed to the first supporting surface, and a support portion located in the first recess is provided on the first supporting surface. One end of the flexible printed circuit board is bound to the liquid crystal display panel, and the other end of the flexible printed circuit board passes through the first recess and is bent to be placed on the back side of the backlight module. The support portion is used to support the flexible printed circuit board in the first recess.

[0007] In the above-mentioned display device, the sidewall of one end of the frame is recessed to form a second clearance groove. The second clearance groove and the first clearance groove are located at the same end of the frame and are interconnected. The other end of the flexible printed circuit board passes through the first clearance groove, is bent for the first time to pass through the second clearance groove, and is bent for the second time to be placed on the back of the backlight module.

[0008] In the above-mentioned display device, the first side of the support portion near the second recess is flush with the first surface of the second recess near the support portion.

[0009] In the above-mentioned display device, the liquid crystal display panel includes a thin film transistor array substrate. The flexible printed circuit board is bonded to one end of the thin film transistor array substrate near the support portion. An adhesive layer for fixing the flexible printed circuit board is disposed on the second side of the thin film transistor array substrate near the support portion and the end of the thin film transistor array substrate bonded to the flexible printed circuit board. The adhesive layer and the support portion have a first preset distance.

[0010] In the above-described display device, the first plane of the thin-film transistor array substrate is located on the side of the second plane of the support portion away from the first support surface, the vertical distance between the first plane and the second plane is a second preset distance, the first plane of the thin-film transistor array substrate is the plane for bonding the flexible printed circuit board, and the second plane of the support portion is the plane of the support portion away from the first support surface.

[0011] In the above-described display device, the length of the support portion along the first direction is greater than the length of the flexible printed circuit board along the first direction, and the first direction is perpendicular to and parallel to the direction in which the support portion points toward the liquid crystal display panel.

[0012] In the above-mentioned display device, the support portion is a protrusion.

[0013] In the above-mentioned display device, the surface of the support portion that contacts the flexible printed circuit board is an arc-shaped surface.

[0014] In the aforementioned display device, the support portion is a hard rubber block.

[0015] A plastic frame has a first support surface, a second support surface protruding from the first support surface, and a first clearance groove formed between the first support surface and the second support surface, wherein a support portion located in the first clearance groove is provided on the first support surface.

[0016] A backlight module, the backlight module comprising the aforementioned plastic frame.

[0017] Beneficial effects: This application provides a frame, a backlight module, and a display device. By providing a support portion in the first recess of the frame for accommodating the flexible printed circuit board, the support portion supports the flexible printed circuit board when it is subjected to tension while assembled on the backlight module, preventing excessive stretching of the flexible printed circuit board. The force is applied to the liquid crystal display panel through the end of the flexible printed circuit board that is bonded to the liquid crystal display panel, causing local changes in the cell thickness of the liquid crystal display panel. This results in uneven brightness in local areas when the display device is used, thereby improving the user's visual experience. Attached Figure Description

[0018] Figure 1 This is a perspective view of the display device according to an embodiment of this application;

[0019] Figure 2 for Figure 1 A partial enlarged view of the display device shown;

[0020] Figure 3 for Figure 1 A cross-sectional schematic diagram of the display device shown.

[0021] The attached icon is shown below:

[0022] 10 LCD display panel; 20 Flexible printed circuit board; 30 Backlight module; 40 Support unit;

[0023] 100 Thin-film transistor array substrate; 101 Color filter substrate; 100a First plane; 100b Second side;

[0024] 50 Colloidal layer; d1 First preset distance; 301 Frame; 301a First support surface; 301b Second support surface; 3011 First clearance groove; 3012 Second clearance groove; 302 Back plate; 303 Light guide plate; 304 Point light source; 305 Optical film; 40a Second plane; 40b First side surface; 40c Curved surface; 3012a First surface. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0026] Please see Figures 1-3 , Figure 1 This is a perspective view of the display device according to an embodiment of this application. Figure 2 for Figure 1 A partial enlarged view of the display device shown. Figure 3for Figure 1 The diagram shows a cross-sectional view of the display device. The display device is an in-vehicle LCD display device. The display device includes an LCD panel 10, a flexible printed circuit board 20, a backlight module 30, and a support 40.

[0027] The liquid crystal display panel 10 includes a thin-film transistor array substrate 100 and a color filter substrate 101. The color filter substrate 101 is disposed opposite to the thin-film transistor array substrate 100. The thin-film transistor array substrate 100 extends to one side relative to the color filter substrate 101 to form an extension region. Both the thin-film transistor array substrate 100 and the color filter substrate 101 are cuboid in shape.

[0028] The thin-film transistor array substrate 100 has a first plane 100a opposite to the color filter substrate 101 and a second side surface 100b near the support portion 40. The first plane 100a and the second side surface 100b are perpendicular to each other. The second side surface 100b is located at one end of the thin-film transistor array substrate 100 near the support portion 40. A flexible printed circuit board 20 is bonded to one end of the thin-film transistor array substrate 100 near the support portion 40. Specifically, one end of the flexible printed circuit board 20 is fixed to the first plane 100a of the extension area of ​​the thin-film transistor array substrate 100 by hot pressing.

[0029] A colloid layer 50 is provided on the second side 100b of the thin-film transistor array substrate 100, near the support portion 40, to fix the flexible printed circuit board 20. This prevents the end of the flexible printed circuit board 20 bonded to the thin-film transistor array substrate 100 from separating from the substrate and avoids stress concentration at the bonded end, which could lead to breakage of the flexible printed circuit board 20. A first predetermined distance d1 is maintained between the colloid layer 50 and the support portion 40 to prevent contact and assembly interference. The colloid layer 50 is a UV-curable adhesive. The colloid layer 50 is coated and formed on the second side 100b of the thin-film transistor array substrate 100. The first predetermined distance d1 is greater than or equal to 0.5 mm.

[0030] The backlight module 30 includes a frame 301, which has a first support surface 301a, a second support surface 301b protruding from the first support surface 301a, a first recessed groove 3011, and a second recessed groove 3012. A stepped area is formed between the first support surface 301a and the second support surface 301b to accommodate the flexible printed circuit board 20. This stepped area is the first recessed groove 3011, which is formed between the first support surface 301a and the second support surface 301b. The sidewall at one end of the frame 301 is recessed to form the second recessed groove 3012, which also serves to accommodate the flexible printed circuit board 20. The second recessed groove 3012 and the first recessed groove 3011 are located at the same end of the frame 301 and are interconnected. One end of the flexible printed circuit board 20 is bonded to the liquid crystal display panel 10, and the other end of the flexible printed circuit board 20 passes through the first recess 3011, is bent for the first time to pass through the second recess 3012, and is bent for the second time to be placed on the back of the backlight module 30.

[0031] It is understandable that the sidewall of the frame 301 may not have the second recessed groove 3012. The other end of the flexible printed circuit board 20 passes through the first recessed groove 3011, is bent once, passes through the sidewall, and is bent a second time to be placed on the back of the backlight module 30. That is, the other end of the flexible printed circuit board 20 passes through the first recessed groove 3011 and is bent to be placed on the back of the backlight module 30. The flexible printed circuit board 20 is housed in the second recessed groove 3012 to prevent damage to the flexible printed circuit board 20.

[0032] Specifically, the frame 301 includes a hollow rectangular base frame with a first support surface 301a, to which the liquid crystal display panel 10 is fixed. A plane on the thin-film transistor array substrate 100 opposite to the first plane 100a is fixed to the first support surface 301a of the rectangular base frame using double-sided adhesive or foam adhesive. An annular protrusion is formed around the outer edge of the first support surface 301a, and the plane of the annular protrusion away from the first support surface 301a is a second support surface 301b. The second support surface 301b supports a cover plate, touch panel, or front frame disposed on the side of the liquid crystal display panel 10 away from the backlight module 30. A notch is formed on the annular protrusion to expose the first support surface 301a, and a step area is formed between the first support surface 301a and the second support surface 301b at the notch. The frame 301 also includes a side wall surrounding the rectangular base frame. The side wall of the frame 301 at the end where the first clearance groove 3011 is provided is recessed inward to form a second clearance groove 3012. The second clearance groove 3012 communicates with the first clearance groove 3011. The widths of the first clearance groove 3011 and the second clearance groove 3012 are equal and greater than the width of the flexible printed circuit board 20, so that the flexible printed circuit board 20 can pass through the first clearance groove 3011 and the second clearance groove 3012.

[0033] The backlight module 30 also includes a backplate 302, a light guide plate 303, a point light source 304, and an optical film 305. A frame 301 is fixed to the backplate 302. The light guide plate 303 is disposed within the backplate 302. The point light source 304 is disposed on the inner wall of the sidewall of the backplate 302 and faces the side of the light guide plate 303. The optical film 305 is disposed on the side where the light-emitting surface of the light guide plate 303 is located. The point light source 304 is a light-emitting diode (LED). The light emitted by the point light source 304 is processed by the light guide plate 303 to form a surface light source. After being processed by the optical film 305, the brightness of the light incident on the liquid crystal display panel 10 is uniform.

[0034] The support portion 40 is a protrusion. The support portion 40 has a second plane 40a and a first side surface 40b. The second plane 40a of the support portion 40 is the plane of the support portion 40 away from the first support surface 301a; that is, the second plane 40a of the support portion 40 is the top surface of the support portion 40, and the second plane 40a of the support portion 40 is located on the side of the second support surface 301b closest to the first support surface 301a. The first side surface 40b of the support portion 40 is the side of the support portion 40 closest to the second recessed groove 3012. The first side 40b of the support portion 40 near the second recess groove 3012 is flush with the first surface 3012a of the second recess groove 3012 near the support portion 40, so that the flexible printed circuit 20 can be directly housed in the second recess groove 3012 after being supported and bent by the support portion 40. This avoids the flexible printed circuit board 20 transitioning from the support portion 40 to the second recess groove 3012 needing to be bent again to enter the second recess groove 3012, and avoids the flexible printed circuit board 20 being subjected to excessive stress.

[0035] The support portion 40 can be rectangular, in which case the first side surface 40b and the second plane 40a are perpendicular to each other. Furthermore, the surface of the support portion 40 that contacts the flexible printed circuit board 20 is an arc-shaped surface 40c. This is achieved by chamfering the right-angle corner between the first side surface 40b and the second plane 40a to form an arc-shaped surface 40c, resulting in a smooth arc-shaped surface 40c. This avoids burrs at the corner between the first side surface 40b and the second plane 40a, which could damage the flexible printed circuit board 20. The radius of the arc-shaped surface 40a is 0.3 ± 0.05 mm.

[0036] The support portion 40 can be integrally formed with the frame 301 to simplify the manufacturing process. Alternatively, the support portion 40 can be separate from the frame 301; for example, the support portion 40 can be a rigid rubber block, allowing it to support the flexible printed circuit board 20 while preventing damage. The rigid rubber block can be fixed to the first recess 3011 of the first support surface 301a using double-sided adhesive.

[0037] The length of the support portion 40 along the first direction is equal to the length of the first recessed groove 3011 along the first direction, thus the support portion 40 is connected to the aforementioned annular protrusion. The length of the support portion 40 along the first direction is greater than the length of the flexible printed circuit board 20 along the first direction, to ensure that the support portion 40 can support the entire flexible printed circuit board 20 in the first direction. The first direction is perpendicular to and parallel to the direction in which the support portion 40 points towards the liquid crystal display panel 10 and to the first support surface 301a.

[0038] One end of the flexible printed circuit board 20 is bonded to the liquid crystal display panel 10, and the other end of the flexible printed circuit board 20 passes through the first relief groove 3011 and is bent to be placed on the back side of the backlight module 30. The first plane 100a of the thin film transistor array substrate 100 is located on the side of the second plane 40a of the support portion 40 away from the first support surface 301a. The vertical distance between the first plane 100a and the second plane 40a is a second preset distance d2 to avoid assembly interference caused by the support portion 40 pressing against the flexible printed circuit board 20 due to assembly tolerances and thickness tolerances. That is, after a partial suspension is formed between the flexible printed circuit board 20 and the support portion 40 in the first relief groove 3011, the support portion 40 then supports the flexible printed circuit board 20. The first plane 100a of the thin film transistor array substrate 100 is the plane for bonding the flexible printed circuit board 20. The second preset distance d2 is 0.2 ± 0.05 mm.

[0039] The display device of this application provides a support portion in the first recessed groove of the frame for accommodating the flexible printed circuit board. When the flexible printed circuit board is assembled on the backlight module and subjected to tension, the support portion supports the flexible printed circuit board, preventing it from being excessively stretched. The force is applied to the liquid crystal display panel through the end of the flexible printed circuit board that is bonded to the liquid crystal display panel, causing local changes in the cell thickness of the liquid crystal display panel. This results in local uneven brightness when the display device is used, thereby improving the user's visual experience.

[0040] This application also provides a plastic frame, which has a first support surface, a second support surface protruding from the first support surface, and a first clearance groove formed between the first support surface and the second support surface, wherein a support portion located in the first clearance groove is provided on the first support surface.

[0041] The frame of this application is used to house a support portion in the first recessed groove of the flexible printed circuit board. After the flexible printed circuit board to be assembled passes through the first recessed groove, the support portion supports the flexible printed circuit board, preventing the flexible printed circuit board from being excessively stretched during assembly. The force is applied to the liquid crystal display panel through the end of the flexible printed circuit board that is bound to the liquid crystal display panel, which would cause a change in the local cell thickness of the liquid crystal display panel.

[0042] This application also provides a backlight module, which includes the aforementioned frame.

[0043] The backlight module of this application provides a support portion in the first recessed groove of the frame for accommodating the flexible printed circuit board. When the flexible printed circuit board on the liquid crystal display panel to be installed on the backlight module is assembled on the backlight module, the support portion supports the flexible printed circuit board, preventing the flexible printed circuit board from being excessively stretched. The force is applied to the liquid crystal display panel through the end of the flexible printed circuit board that is bound to the liquid crystal display panel, causing the local cell thickness of the liquid crystal display panel to change.

[0044] The above description of the embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this application; those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A display device, characterized in that, include: A backlight module includes a frame having a first support surface, a second support surface protruding from the first support surface, and a first clearance groove defined by the first support surface and the second support surface; The liquid crystal display panel is fixed to the first support surface; The support portion is disposed on the first support surface in the first clearance groove; A flexible printed circuit board has one opposite end and another end. One end of the flexible printed circuit board is bound to the end of the liquid crystal display panel near the support portion. The flexible printed circuit board passes through the first clearance groove and contacts the support portion. The other end of the flexible printed circuit board is placed on the side of the backlight module away from the liquid crystal display panel. as well as An adhesive layer is disposed on the end face of the liquid crystal display panel near the support portion and spaced apart from the support portion, and is used to bond the flexible printed circuit board to the liquid crystal display panel.

2. The display device according to claim 1, wherein The distance between the colloidal layer and the support portion is greater than or equal to 0.5 mm.

3. The display device according to claim 1, wherein The colloidal layer includes a UV-curable adhesive.

4. The display device according to claim 1, wherein The surface on which the liquid crystal display panel is bonded to the flexible printed circuit board is located on the top surface of the support portion away from the first support surface, on the side opposite to the first support surface, and the second support surface is located on the top surface away from the first support surface.

5. The display device according to claim 4, wherein The support portion also includes an arc-shaped surface, which is located at the corner of the support portion and connected to the top surface, and the flexible printed circuit board is in contact with the arc-shaped surface.

6. The display device according to claim 1, wherein The dimension of the support portion along the first direction is larger than the dimension of the flexible printed circuit board along the first direction, and the first direction is perpendicular to and parallel to the direction in which the support portion points to the liquid crystal display panel.

7. The display device according to claim 1, wherein The support portion includes a rigid rubber block, or the support portion is integrally formed with the rubber frame.

8. The display device according to claim 1, wherein The liquid crystal display panel includes: A thin-film transistor array substrate, wherein one end of the flexible printed circuit board is bonded to one end of the thin-film transistor array substrate near the support portion, and the adhesive layer is disposed on the end face of the thin-film transistor array substrate near the support portion; and A color filter substrate is disposed opposite to the thin-film transistor array substrate and is located on the side of the thin-film transistor array substrate away from the backlight module.

9. The display device according to any one of claims 1 to 8, characterized by The support portion is a protrusion that extends beyond the first support surface; The frame includes: A rectangular base frame, the rectangular base frame including a first support surface disposed around the hollow region; and An annular protrusion is disposed on the first support surface along the outer edge of the rectangular base frame away from the hollow area. The annular protrusion also includes a notch that exposes the first support surface. The notch includes the first clearance groove. The surface of the annular protrusion away from the first support surface is the second support surface.

10. The display device according to any one of claims 1 to 8, characterized by The frame also includes: The second relief groove is formed by the recessed side wall of the frame that is away from the liquid crystal display panel and adjacent to the first relief groove, and communicates with the first relief groove. The first surface of the second relief groove facing the flexible printed circuit board is flush with the first side of the support near the second relief groove. The first surface of the second relief groove facing the flexible printed circuit board is the bottom surface of the second relief groove. The flexible printed circuit board further includes a first bending portion and a second bending portion. The flexible printed circuit board extends from the first recess into the second recess through the first bending portion. The flexible printed circuit board also extends from the second recess into the side of the backlight module away from the liquid crystal display panel through the second bending portion.

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