CN220983684U

CN220983684U - Backlight module and liquid crystal display device

Info

Publication number: CN220983684U
Application number: CN202322364332.5U
Authority: CN
Inventors: 王正超; 吴立; 谢俊烽
Original assignee: HKC Co Ltd; Chuzhou HKC Optoelectronics Technology Co Ltd
Current assignee: HKC Co Ltd; Chuzhou HKC Optoelectronics Technology Co Ltd
Priority date: 2023-08-30
Filing date: 2023-08-30
Publication date: 2024-05-17
Anticipated expiration: 2033-08-30

Abstract

The application relates to a backlight module and a liquid crystal display device. The backlight module comprises a back plate, a light bar and a light guide plate, wherein the light guide plate is positioned on the back plate, the light bar is positioned on one side of a light incident surface of the light guide plate, the light bar comprises a plurality of light beads which are arranged side by side, a plurality of grooves which are continuously distributed are formed on the light incident surface of the light guide plate, and the light beads are accommodated in the grooves; the backlight module further comprises an adhesive tape, wherein the adhesive tape is used for connecting the lamp strip and the light guide plate into a whole. Compared with the prior art that the light bar is attached to the side edge of the back plate, the light guide plate is arranged above the back plate, and a gap exists between the light guide plate and the light bar, so that the relative positions of the light guide plate and the light bar are prevented from being changed due to heat released by the work of the light bar, and the display effect is improved.

Description

Backlight module and liquid crystal display device

Technical Field

The present application relates to the field of display technologies, and in particular, to a backlight module and a liquid crystal display device.

Background

The backlight module in the liquid crystal display device generally comprises a back plate, a light guide plate and a light bar, and the backlight module provides a light source for the liquid crystal display panel.

In the prior art, the light bar is attached on the side edge of the back plate, the light guide plate is placed above the back plate, and a gap exists between the light guide plate and the light bar.

However, in the prior art, a large amount of heat is generated when the light bar is lighted for a long time, the light guide plate is heated and expanded, the gap between the light guide plate and the light bar is reduced due to the heated and expanded light guide plate, and the relative positions of the light guide plate and the light bar are changed, so that the display effect of the liquid crystal display device is affected.

Disclosure of utility model

The application aims to provide a backlight module and a liquid crystal display device, which are used for solving the technical problem that the relative positions of a light guide plate and a light bar are changed by heat generated by the light bar, so that the display effect of the liquid crystal display device is affected.

In a first aspect, an embodiment of the present application provides a backlight module, including a back plate, a light bar, and a light guide plate, where the light guide plate is located on the back plate, the light bar is located on one side of a light incident surface of the light guide plate, and the light bar includes a plurality of light beads arranged side by side, and the backlight module is characterized in that a plurality of grooves are formed on the light incident surface of the light guide plate, and the light beads are accommodated in the grooves; the backlight module further comprises an adhesive tape, wherein the adhesive tape is used for connecting the lamp strip and the light guide plate into a whole.

In one possible embodiment, the grooves taper in the light-emitting direction of the lamp beads.

In one possible embodiment, the light incident surface of the light guide plate further includes a planar portion located between the plurality of grooves.

The lamp strip still includes the circuit board, and a plurality of lamp pearls set up on the circuit board, and the circuit board is laminated with planar portion.

In one possible embodiment, the tape is black in color and is disposed on the backlight side of the light bar.

In one possible embodiment, the backlight module further includes an optical film, the optical film is located on the light emitting side of the light guide plate, and the adhesive tape is used for connecting the light bar, the light guide plate and the optical film into a whole.

In one possible implementation, the backlight module further includes a reflective sheet disposed between the back plate and the light guide plate, and the adhesive tape is further used to connect the reflective sheet, the light bar and the optical film into a whole.

In one possible embodiment, the adhesive tape includes a first connecting portion and a second connecting portion connected to each other, the first connecting portion is attached to an upper edge of the optical film, and the second connecting portion is attached to a side surface of the optical film, a side surface of the circuit board facing away from the lamp beads, and a side surface of the reflecting sheet.

In one possible implementation manner, the light emitting side of the backlight module is provided with a liquid crystal display panel, the liquid crystal display panel comprises a display area and a non-display area located at the peripheral side of the display area, the length of the display area is l _AA, the length of the light guide plate is l _LGP, and the length l _x of the first connecting portion satisfies the following relationship:

l_x＝l_AA-l_LGP-htanθ，

Wherein θ is the angle between the line of sight of the user and the light emitting direction, and h is the distance between the optical film and the liquid crystal display panel.

In one possible embodiment, the length of the second connection portion is greater than or equal to the sum of the thickness of the optical film, the thickness of the light guide plate, and the thickness of the reflective sheet.

In a second aspect, an embodiment of the present application further provides a liquid crystal display device, including: a liquid crystal display panel; and the backlight module is arranged on one side of the backlight surface of the liquid crystal display panel and is used for providing a light source for the liquid crystal display panel.

According to the backlight module and the liquid crystal display device provided by the embodiment of the application, the backlight module is used for connecting the lamp strip and the light guide plate into a whole in advance through the adhesive tape, so that the relative position between the lamp strip and the light guide plate is prevented from being changed due to heat generated by light emission of the lamp beads, and the display effect is improved; meanwhile, a plurality of continuous grooves are formed in the light incident surface of the light guide plate, and the lamp beads in the lamp strip are embedded into the grooves, so that narrow frame design can be realized, and the attractiveness is improved.

Drawings

Features, advantages, and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings. In the drawings, like parts are designated with like reference numerals. The drawings are not drawn to scale, but are merely for illustrating relative positional relationships, and the layer thicknesses of certain portions are exaggerated in order to facilitate understanding, and the layer thicknesses in the drawings do not represent the actual layer thickness relationships.

Fig. 1 is a schematic diagram showing a structure of a backlight module and a liquid crystal display device including the backlight module according to an embodiment of the application;

fig. 2 shows a top view of a light guide plate and a light bar in a backlight module according to an embodiment of the application;

Fig. 3 is a schematic diagram showing an enlarged area structure of a backlight module and a liquid crystal display device including the backlight module according to an embodiment of the application.

Reference numerals illustrate:

100. A backlight module;

1. A back plate;

2. a light bar; 21. a lamp bead; 22. a circuit board;

3. A light guide plate; 31. a groove; 32. a planar portion;

4. an adhesive tape; 41. a first connection portion; 42. a second connecting portion;

5. An optical film; 6. a reflection sheet; 7. a rubber frame;

200. A liquid crystal display panel;

AA. A display area; NA, non-display area.

Detailed Description

Features and exemplary embodiments of various aspects of the application are described in detail below. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the application. It will be apparent, however, to one skilled in the art that the present application may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the application by showing examples of the application. In the drawings and the following description, at least some well-known structures and techniques have not been shown in detail in order not to unnecessarily obscure the present application; also, the size of the region structures may be exaggerated for clarity. Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

The backlight module in the lcd device generally comprises a back plate 1, a light guide plate 3 and a light bar 2, and the backlight module 100 provides a light source for the lcd panel 200. In the prior art, a light bar 2 is attached to the side edge of a back plate 1, a light guide plate 3 is placed above the back plate 1, and a gap exists between the light guide plate 3 and the light bar 2.

However, in the prior art, a large amount of heat is generated when the light bar 2 is lighted for a long time, the light guide plate 3 expands due to heat, the gap between the light guide plate 3 and the light bar 2 is reduced due to the expansion of the light guide plate 3, and the relative position between the light guide plate 3 and the light bar 2 is changed, so that the display effect of the liquid crystal display device is affected.

In view of the above, the embodiment of the application provides a backlight module 100 and a liquid crystal display device including the backlight module 100, wherein the backlight module is provided with a plurality of grooves 31 on one side of the light incident surface of the light guide plate 3, and the light bar 2 and the light guide plate 3 are integrally connected by using the adhesive tape 4, and the light beads 21 are accommodated in the grooves 31, so that the light guide plate 3 and the light bar 2 are prevented from being relatively displaced due to heat generated by the working of the light beads 21, and the display effect is further affected.

The following describes a specific structure of a backlight module and a liquid crystal display device including the backlight module according to various embodiments of the present application with reference to the accompanying drawings.

First embodiment

Fig. 1 is a schematic structural diagram of a backlight module and a liquid crystal display device including the same according to an embodiment of the application.

As shown in fig. 1, a first embodiment of the present application provides a liquid crystal display device, which includes a liquid crystal display panel 200 and a backlight module 100 disposed on a backlight surface side of the liquid crystal display panel 200, wherein the backlight module 100 is used for providing a light source to the liquid crystal display panel 200.

The liquid crystal display panel 200 may be a single display panel or may be a double display panel stacked in the thickness direction. When the lcd panel 200 is a dual display panel, the display panel at the bottom layer is used for controlling light, and the display panel at the top layer is used for displaying, so that the contrast ratio of the lcd device can be improved. For convenience of description, embodiments of the present application will be described taking the liquid crystal display panel 200 as a single display panel as an example.

In addition, the lcd device further includes an upper polarizer located on the light-emitting surface side of the lcd panel 200, a lower polarizer (not shown) located on the backlight surface side of the lcd panel 200, and a cover plate located on the upper polarizer facing away from the lcd panel 200. The lower and upper polarizers polarize incident light of the liquid crystal display panel 200 to allow light vibrating only in one direction to be transmitted.

As shown in fig. 1, a backlight module 100 according to a first embodiment of the present application includes a back plate 1, a light bar 2 and a light guide plate 3.

The light guide plate 3 is located on the back plate 1, the light bar 2 is located on one side of the light incident surface of the light guide plate 3, and the light bar 2 comprises a plurality of light beads 21 arranged side by side.

The light incidence surface of the light guide plate 3 is provided with a plurality of grooves 31 which are continuously distributed, and the lamp beads 21 are accommodated in the grooves 31; the backlight module 100 further includes an adhesive tape 4, where the adhesive tape 4 is used to connect the light bar 2 and the light guide plate 3 into a whole.

In this embodiment, the backlight module 100 connects the light bar 2 and the light guide plate 3 into a whole in advance through the adhesive tape 4, so as to avoid the change of the relative position between the light bar and the light guide plate 3 caused by the heat generated by the light emission of the light beads, and improve the display effect; meanwhile, a plurality of continuous grooves 31 are formed in the light incident surface of the light guide plate 3, and the lamp beads 21 in the lamp strip 2 are embedded into the grooves 31, so that narrow frame design can be realized, and the attractiveness is improved.

The material of the back plate 1 may be any metal material, such as an aluminum plate, an aluminum alloy plate, or galvanized steel, and is manufactured by a stamping process. The metal material has better ductility, and can protect the backlight module 100 from being broken easily under the impact of external force. The back plate 1 may also be made of plastic material, such as polyimide, polycarbonate, polyethersulfone, polyethylene terephthalate, polyethylene, etc., so as to reduce the weight of the backlight module 100 and the cost of the backlight module 100. The shape of the back plate 1 may be the same as that of the liquid crystal display panel 200 using the backlight module 100. For example, when the shape of the liquid crystal display panel 200 is circular, the shape of the back plate 1 of the backlight module 100 used therein is also circular. The shape of the back plate 1 may vary from embodiment to embodiment.

The Light beads 21 may be Light-Emitting diodes (LEDs) of a conventional size, or may be any of Micro-LEDs (Micro-LEDs) or sub-millimeter LEDs (Mini-LEDs). Micro-LEDs refer to LED chips with grain sizes below 100 microns, mini-LEDs refer to LED chips with grain sizes of about 100-300 microns. The LED, mini-LED or Micro-LED has the advantages of low power consumption, high brightness, high resolution, high color saturation, high reaction speed, long service life, high efficiency and the like.

In some embodiments, the grooves 31 taper in the light exiting direction of the lamp beads 21. Specifically, the grooves 31 may be slightly saw-toothed, or may be V-shaped.

For example, when the groove 31 is in a micro saw-tooth shape, the groove 31 includes three contact surfaces, namely, a first contact surface, a second contact surface and a third contact surface, wherein two ends of the second contact surface are respectively abutted against the first contact surface and the third contact surface, and the second contact surface is perpendicular to the light guide plate 3, such as the light direction, and parallel to the light guide plate 3. The first contact surface and the third contact surface can guide the light emitted by the lamp beads 21 from the edge direction to the viewing direction, so that the light is prevented from being wasted, and the brightness of the light guide plate 3 is increased.

When the shape of the groove 31 is V-shaped, after the light beam of the lamp bead 21 is injected into the V-shaped groove 31, the V-shaped groove 31 can collect the light beam, and the light beam is converged, so that the light beam is prevented from being reflected in the light guide plate 3 in a non-directional manner, and further the waste of light energy is avoided.

In some embodiments, the light incident surface of the light guide plate 3 further includes planar portions 32 between the plurality of grooves 31, and the grooves 31 and the planar portions 32 are alternately arranged. The light bar 2 further includes a circuit board 22, the plurality of light beads 21 are disposed on the circuit board 22, and the circuit board 22 is attached to the planar portion 32.

Specifically, as shown in the top view of the light guide plate 3 and the light bar 2 in the backlight module 100 provided in the embodiment of the application in fig. 2, the light bar 2 includes a plurality of light beads 21 and a circuit board 22 that are arranged side by side, the light beads 21 are arranged on the circuit board 22, a plurality of grooves 31 are distributed on the light incident surface of the light guide plate 3, a planar portion 32 is located between the two grooves 31, the light beads 21 are embedded in the grooves 31, the circuit board 22 is attached to the planar portion 32, and the light guide plate 3 is integrally connected with the light bar 2.

In some embodiments, the color of the adhesive tape 4 is black, and the adhesive tape 4 is disposed on the backlight side of the light bar 2. The black adhesive tape 4 arranged on the backlight side of the lamp strip 2 can effectively avoid the situation of edge light leakage and improve the display quality.

In some embodiments, the backlight module 100 further includes an optical film 5, the optical film 5 is located on the light emitting side of the light guide plate 3, and the adhesive tape 4 is used to connect the light bar 2, the light guide plate 3 and the optical film 5 together.

The optical film 5 includes a diffusion plate, a prism sheet, a protective sheet, and the like. The diffusion plate is used for diffusing the light emitted from the light emitting element to equalize the brightness of the entire backlight module 100. The prism sheet is used to control the propagation direction of light diffused by the diffusion plate such that the propagation direction of light is perpendicular to the liquid crystal display panel 200. The protective sheet is used to protect the prisms of the prism sheet from scratches and the like. The protective sheet may also be used to widen the viewing angle previously narrowed due to the prism sheet.

In some embodiments, the backlight module 100 further includes a reflective sheet 6, the reflective sheet 6 is disposed between the back plate 1 and the light guide plate 3, and the adhesive tape 4 is further used to connect the reflective sheet 6 with the light bar 2 and the optical film 5 into a whole.

The reflector 6 may be made of a plastic material. For example, polyethylene terephthalate (PET), polycarbonate (PC), polystyrene (PS), and the like. The reflective sheet 6 may also include a highly reflective coating, such as titanium dioxide TiO ₂, applied to the plastic material to increase the light reflectance.

In some embodiments, the adhesive tape 4 includes a first connection portion 41 and a second connection portion 42 connected to each other, the first connection portion 41 is attached to the upper edge of the optical film 5, and the second connection portion 42 is attached to the side of the optical film 5, the side of the circuit board 22 facing away from the lamp beads 21, and the side of the reflection sheet 6.

The light emitting side of the backlight module 100 is provided with a liquid crystal display panel 200, the liquid crystal display panel 200 comprises a display area AA and a non-display area NA positioned on the periphery of the display area AA, the length of the display area AA is l _AA, the length of the light guide plate 3 is l _LGP, and the length l _x of the first connecting portion 41 satisfies the following relationship:

l_x＝l_AA-l_LGP-htanθ，

Where θ is an angle between the line of sight of the user and the light emitting direction, and h is a distance between the optical film 5 and the liquid crystal display panel 200.

Specifically, fig. 3 shows a schematic diagram of an area enlarged structure of a backlight module and a liquid crystal display device including the backlight module according to an embodiment of the present application, as shown in fig. 3, according to the length of the display area AA being l _AA, the length of the light guide plate 3 being l _LGP, an included angle θ between a line of sight of a user and a light emitting direction, and a distance h between the optical film 5 and the liquid crystal display panel 200, the following formula is adopted:

l_x＝l_AA-l_LGP-htanθ

The length l _x of the first connecting portion 41 is acquired.

In this embodiment, if the length of the first connection portion 41 is too long, the display area AA is blocked, and the display panel displays black edges; if the length of the first connection portion 41 is too short, the optical film 5 and the circuit board 22 will be loosened, and the first connection portion 41 with a proper length will not block the display area AA or cause the optical film 5 and the circuit board 22 to be loosened.

The length of the second connection portion 42 is greater than or equal to the sum of the thickness of the optical film 5, the thickness of the light guide plate 3, and the thickness of the reflection sheet 6.

In some embodiments, the backlight module 100 further includes a glue frame 7, and the glue frame 7 is disposed around the edge of the back plate 1. The rubber frame 7 is usually made of plastic material, such as polycarbonate, and has better elasticity. In the transportation and use process of the backlight module 100, the rubber frame 7 can provide a better buffering effect for the structures such as the light emitting component and the optical component, so as to prevent the structures such as the light emitting component and the optical component from directly striking the back plate 1 to be damaged. Alternatively, the adhesive frame 7 and the back plate 1 may be adhered together by the double-sided adhesive tape 4 after the respective fabrication is completed. Alternatively, after the back plate 1 is stamped and formed, the back plate may be integrally injection molded with the rubber frame 7 as an insert.

When the backlight module is assembled in the related art, the light bar 2 is fixed on the side part of the back plate 1, the light guide plate 3 is fixed on the light emitting side of the back plate 1, and then the light incident surface of the light guide plate 3 is aligned with the light beads of the light bar 2, so that when the light guide plate 3 is deformed due to thermal expansion, the relative position between the light guide plate 3 and the light bar 2 changes, and the display effect is affected.

In this embodiment, the light guide plate 3 and the light guide plate 2 are assembled into a whole in advance by the adhesive tape, and then the components, such as the back plate 1, the reflecting sheet 6, the optical film 5, the adhesive frame 7 and the like, are assembled into the backlight module, so that the relative position between the light guide plate 3 and the light guide plate 2 is prevented from being changed due to the heat generated by the light emission of the light beads, and the display effect is improved. In addition, the preassembled light guide plate 3 and the light bar 2 can omit the alignment process of the light incident surface of the light guide plate 3 and the light bar 2, thereby simplifying the assembly process and improving the production efficiency.

In addition, in this embodiment, by arranging a plurality of grooves 31 on one side of the light incident surface of the light guide plate 3, the grooves 31 accommodate the lamp beads 21 of the light guide plate 2, and the light guide plate 3 and the light guide plate 2 are integrally connected by the adhesive tape 4, compared with the case that the light guide plate 3 is attached to the side edge of the back plate 1 in the prior art, the light guide plate 3 is placed above the back plate 1, and a gap exists between the light guide plate 3 and the light guide plate 2, after the light guide plate 2 works for a long time to generate heat, the gap between the light guide plate 3 and the light guide plate 2 can be prevented from being reduced due to the thermal expansion of the light guide plate 3, and the relative position of the light guide plate 3 and the light guide plate 2 is prevented from being changed, so that the display effect of the liquid crystal display device is prevented from being affected.

The present application provides a liquid crystal display device, comprising: a liquid crystal display panel 200; and the backlight module 100 is disposed on the backlight surface side of the liquid crystal display panel 200, and the backlight module 100 is used for providing light source for the liquid crystal display panel 200.

It can be appreciated that the technical solution of the backlight module provided by the embodiments of the present application can be widely used for providing light sources for various liquid crystal display panels, such as TN (TWISTED NEMATIC ) display panels, IPS (In-PLANE SWITCHING ) display panels, VA (VERTICAL ALIGNMENT, vertically aligned) display panels, MVA (Multi-Domain VERTICAL ALIGNMENT, multi-Domain vertically aligned) display panels.

It should be readily understood that the terms "on … …", "above … …" and "above … …" in this disclosure should be interpreted in the broadest sense so that "on … …" means not only "directly on something" but also includes "on something" with intermediate features or layers therebetween, and "above … …" or "above … …" includes not only the meaning "on something" or "above" but also the meaning "above something" or "above" without intermediate features or layers therebetween (i.e., directly on something).

The term "layer" as used herein may refer to a portion of material that includes regions having a certain thickness. The layer may extend over the entire underlying or overlying structure, or may have a range that is less than the range of the underlying or overlying structure. Further, the layer may be a region of a continuous structure, either homogenous or non-homogenous, having a thickness less than the thickness of the continuous structure. For example, the layer may be located between the top and bottom surfaces of the continuous structure or between any pair of lateral planes at the top and bottom surfaces. The layers may extend laterally, vertically and/or along a tapered surface. The substrate base may be a layer, may include one or more layers therein, and/or may have one or more layers located thereon, and/or thereunder. The layer may comprise a plurality of layers. For example, the interconnect layer may include one or more conductors and contact layers (within which contacts, interconnect lines, and/or vias are formed) and one or more dielectric layers.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application.

Claims

1. The backlight module comprises a back plate, a light bar and a light guide plate, wherein the light guide plate is positioned on the back plate, the light bar is positioned on one side of the light incident surface of the light guide plate, the light bar comprises a plurality of light beads arranged side by side,

The light incident surface of the light guide plate is provided with a plurality of grooves which are distributed continuously, and the lamp beads are accommodated in the grooves; the backlight module further comprises an adhesive tape, wherein the adhesive tape is used for connecting the lamp strip and the light guide plate into a whole.

2. The backlight module according to claim 1, wherein the grooves taper along the light emitting direction of the lamp beads.

3. The backlight module according to claim 2, wherein the light incident surface of the light guide plate further comprises a planar portion between the plurality of grooves;

The lamp strip also comprises a circuit board, wherein the lamp beads are arranged on the circuit board, and the circuit board is attached to the plane part.

4. The backlight module according to claim 1, wherein the adhesive tape is black in color, and the adhesive tape is disposed on a backlight side of the light bar.

5. A backlight module according to claim 3, further comprising an optical film, wherein the optical film is located on the light emitting side of the light guide plate, and the adhesive tape is used for integrally connecting the light bar, the light guide plate and the optical film.

6. A backlight module according to claim 5, further comprising a reflective sheet disposed between the back plate and the light guide plate, wherein the adhesive tape is further used to connect the reflective sheet, the light bar and the optical film into a whole.

7. The backlight module according to claim 6, wherein the adhesive tape comprises a first connecting portion and a second connecting portion which are connected with each other, the first connecting portion is attached to the upper edge of the optical film, and the second connecting portion is attached to the side surface of the optical film, the side surface of the circuit board away from the lamp beads, and the side surface of the reflecting sheet.

8. The backlight module according to claim 7, wherein the light emitting side of the backlight module is provided with a liquid crystal display panel, the liquid crystal display panel comprises a display area and a non-display area located at a peripheral side of the display area, the length of the display area is k _AA, the length of the light guide plate is l _LGP, and the length l _x of the first connecting portion satisfies the following relationship:

l_x＝l_AA-l_LGP-htanθ，

and (2) wherein θ is an included angle between the sight line of the user and the light emitting direction, and h is a distance between the optical film and the liquid crystal display panel.

9. The backlight module according to claim 7, wherein a length of the second connection portion is greater than or equal to a sum of a thickness of the optical film, a thickness of the light guide plate, and a thickness of the reflection sheet.

10. A liquid crystal display device, comprising:

A liquid crystal display panel; and

The backlight module according to any one of claims 1 to 9, disposed on a backlight side of the liquid crystal display panel, the backlight module being configured to provide a light source to the liquid crystal display panel.