CN202361206U - Backlight module and liquid crystal display device - Google Patents

Abstract

The utility model discloses a backlight module which comprises a light guide plate, a light source set, an optical membrane set and a reflective sheet. The light source set is positioned at the side edge of the light guide plate and is attached onto a liquid crystal panel; the optical membrane set is arranged above the light guide plate; the reflective sheet is provided with a body, a side wall and a reflection part; the body is arranged below the light guide plate and covers the light guide plate; the side wall extends upwards from the body; and the reflection part extends inward from the side wall and is attached to the edge of the liquid crystal panel. According to the backlight module, a glue frame, a lower iron frame and an upper iron frame are saved, but the reflective sheet is utilized to fix the light source set and the optical membrane set, so that the cost of a die is saved, the thickness of the backlight module can be reduced and the assembling step is simplified.

Description

Backlight module and liquid crystal display device

technical field

The utility model relates to the field of liquid crystal display manufacture, in particular to a backlight module and a liquid crystal display device.

Background technique

Liquid crystal display (LCD) uses the change of the electric field strength clamped on the liquid crystal molecules to change the orientation of the liquid crystal molecules to control the intensity of light transmission to display images. Generally speaking, a complete liquid crystal display panel must have a backlight module, a polarizer, a thin-film transistor (TFT) lower substrate, a color filter (CF) upper substrate, and a liquid crystal molecule layer filled in a box composed of two substrates. . The liquid crystal display is a passive light-emitting display device, that is to say, the liquid crystal substrate itself cannot emit light, and the light source needs to be provided by the backlight module. The backlight module is generally composed of a backplane, a light source, a diffusion plate and various optical films.

Generally, the backlight module is divided into direct type and edge type according to the position of the light source. The light source of the direct-type backlight module is located at the bottom of the backlight module. The light utilization rate of the light source of the direct-type backlight module is relatively high, but the light of the direct-type light source will form an alternating light and dark area, so a diffuser with a high haze is required. Board and larger light box distance to solve this problem, increasing the thickness of the backlight module. The light source of the side-light backlight module is located on one side of the backlight module, and the light emitted by the light source is converted into a surface light source through the light guide plate to meet the brightness and uniformity requirements. The side-light backlight module The light utilization rate is relatively low, but it has the advantages of simple process, light and thin volume.

Please refer to FIG. 1 , which is a schematic cross-sectional structure diagram of an existing edge-lit backlight module. The backlight module includes a light source group 11 , a lower iron frame 16 , a reflector 12 , a light guide plate 13 , and a plastic frame 14 And the optical film 15, the plastic frame 14 is assembled on the lower iron frame 16, and then the optical elements, such as the reflector 12, the light source group 11, the light guide plate 13, and the optical film 15 are installed in the plastic frame 14 and fixed . As far as the backlight module is concerned, the lower iron frame 16 is to provide the function of the backlight module and its structural strength, while the plastic frame 14 is used to place and fix optical components such as reflectors 12, light source groups 11, light guide plates 13, A plurality of optical films 15.

At present, most LCD screens use CCFL (Cold Cathode Fluorescent) backlight modules. Due to the limitation of CCFL's luminous characteristics, LCD TVs using CCFL backlight modules have poor color reproduction. With the development of LED (light-emitting diode) technology, LED is gradually applied to the backlight module of LCD display. The light source provided by LED backlight module has the advantages of good color reproduction, high contrast, high brightness and fast light control speed. . As shown in Figure 2, the Chinese patent application with the application number 200920049769.7 discloses a backlight module, which includes a metal protective frame 1, a reflection sheet 2, a light guide plate 3, and a diffusion sheet assembled sequentially from the back to the front. 4. The lower brightness enhancement sheet 5, the upper brightness enhancement sheet 6 and the light-shielding sheet 7. The side of the light guide plate is provided with an LED light source assembly, and the LED light source assembly is composed of a number of LED lamps connected in series. A light string 8 and a flexible circuit board 9 by welding, and a plastic frame 10 is installed under the LED light source assembly.

However, as far as the overall structure of the backlight module is concerned, optical components are indispensable. Therefore, in order to reduce costs, other components must be considered to replace the original plastic frame so that it has the ability to place and fix the original plastic frame. Component structure and function. Therefore, how to use other components to replace the plastic frame of the backlight module is really a difficult problem to be overcome by the relevant industry.

Utility model content

The purpose of the utility model is to provide a backlight module and a liquid crystal display device, so as to save mold costs, reduce the thickness of the backlight module, and simplify assembly steps.

In order to solve the above technical problems, the utility model provides a backlight module, including: a light guide plate, a light source group, an optical film group and a reflection sheet, the light source group is located on the side of the light guide plate and attached to a liquid crystal On the panel, the optical film group is arranged above the light guide plate, the reflector has a body, a side wall and a reflex portion, the body is arranged under the light guide plate and covers the light guide plate, the The side wall extends upward from the body, and the reflex portion extends inward from the side wall and is attached to the edge of the liquid crystal panel.

Optionally, in the backlight module, the body is attached to the light guide plate by double-sided adhesive or thermosetting adhesive.

Optionally, in the backlight module, the reflexed portion is attached to the edge of the liquid crystal panel by double-sided adhesive or thermosetting adhesive.

Optionally, in the backlight module, the light source group is attached to the edge of the liquid crystal panel by double-sided adhesive or thermosetting adhesive.

Optionally, in the backlight module, the light source group is located on one side of the light guide plate.

Optionally, in the backlight module, the light source groups are located on both sides of the light guide plate.

Optionally, in the backlight module, the optical film set includes a lower diffusion sheet, a lower brightness enhancement sheet, an upper brightness enhancement sheet and an upper diffusion sheet from bottom to top.

According to another aspect of the present invention, there is also provided a liquid crystal display device, which includes a liquid crystal panel and the above-mentioned backlight module.

Compared with the prior art, the backlight module of the present invention omits the plastic frame, the lower iron frame and the upper iron frame, but uses the reflector to fix the light source group and the optical film group, which saves the cost of the mold and can reduce the The thickness of the backlight module simplifies the assembly steps.

Description of drawings

FIG. 1 is a schematic cross-sectional structure diagram of an existing backlight module;

FIG. 2 is a schematic cross-sectional structure diagram of another existing backlight module;

3 is a schematic cross-sectional structure diagram of a backlight module according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of assembly of a backlight module according to an embodiment of the present invention.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail. It should be noted that the drawings are all in very simplified form and use imprecise ratios, which are only used to facilitate and clearly assist the purpose of illustrating the embodiment of the present utility model.

As shown in FIG. 3 , the backlight module provided by an embodiment of the present utility model includes: a light guide plate 110 , a light source group 120 , an optical film group 130 and a reflector 140 , and the light source group 120 is located on the side of the light guide plate 110 and attached to the liquid crystal panel 200, the optical film group 130 is arranged above the light guide plate 110, the reflector 140 has a body 141, a side wall 142 and a reflexed portion 143, and the body 141 is arranged on The light guide plate 110 is below and covers the light guide plate 110 , the side wall 142 extends upward from the body 141 , and the reflex portion 143 extends inward from the side wall 142 and is attached to the light guide plate 110 . edge of the liquid crystal panel 200 . In this way, the reflective sheet 140 can be used to fix the light source group 120 and the optical film group 130 , which saves mold costs, reduces the thickness of the backlight module, and simplifies assembly steps.

It should be noted that the backlight module can omit the backplane, and the body 141 is directly attached to the light guide plate 110 by double-sided adhesive or thermosetting adhesive, thereby further reducing the thickness of the backlight module.

The reflexed part 143 of the reflection sheet 140 can be attached to the edge of the liquid crystal panel 200 by double-sided adhesive or thermosetting adhesive, which can be formed by PET polyester or other plastics, and has white or other light reflection effect s surface. The optical film group 130 may include a lower diffusion sheet, a lower brightness enhancement sheet, an upper brightness enhancement sheet, and an upper diffusion sheet from bottom to top (from a direction close to the light guide plate 110 to a direction away from the light guide plate 110). Corresponding addition or deletion of optical films is required. Since the structure of the optical film group 130 is a technical means well known to those skilled in the art, it will not be repeated here.

The light source group 120 is preferably composed of a PCB (Printed Circuit Board, printed circuit board) and an LED (Light Emitting Diode, light emitting diode) arranged on the PCB. The light source provided by the LED light source group has good color reproduction, high contrast ratio, and high brightness. The advantages of high and fast lighting control speed. The light source group 120 can be located on one side of the light guide plate 110 , or can be located on both sides of the light guide plate 110 as shown in FIG. 3 . The light source group 120 can be attached to the edge of the liquid crystal panel 200 by double-sided adhesive or thermosetting adhesive, so as to achieve the purpose of fixing the light source group 120 .

Assuming that the length of the light guide plate 110 is H1, the length of the liquid crystal panel 200 is H2, the width of the light source group is H3, the length of the display area of the liquid crystal display device is H4, the width of the reflexed portion 143 is H5, and the reflection sheet 140 itself The thickness is negligible, then, as shown in FIG. 3, when the light source group 120 is located on both sides of the light guide plate 110, and the reflex portions 143 on the left and right sides of the liquid crystal panel 200 are symmetrical, then:

H1=H2-2*H3;

H4=H2-2*H5;

Correspondingly, if the light source group 120 is only located on one side of the light guide plate 110, then:

H1=H2-H3;

H4=H2-H5.

Referring to Fig. 3 and Fig. 4, the assembly process of the backlight module is as follows: first, stick the double-sided tape on the liquid crystal panel 200, then stick the light source assembly 120 on the double-sided tape, then put the optical film group 130 and The light guide plate 110 is installed on the back of the liquid crystal panel 200, and finally the reflective sheet 140 is assembled, and the reflective sheet turned over to the front of the liquid crystal panel 200 is bent to form a reflexion portion 143, and the reflexion portion 143 is passed through double-sided adhesive tape or thermosetting The whole assembly can be completed by attaching the glue to the edge of the liquid crystal panel 200, and the whole assembly process is convenient and quick.

According to another aspect of the present invention, there is also provided a liquid crystal display device, which includes a liquid crystal panel and the above-mentioned backlight module, which will not be described in detail here.

It should be noted that although the above embodiments have described the utility model in detail, those skilled in the art can make various changes and modifications to the utility model without departing from the spirit and scope of the utility model. In this way, if these modifications and variations of the utility model fall within the scope of the claims of the utility model and equivalent technologies thereof, the utility model is also intended to include these modifications and variations.

Claims (8)

1. module backlight; It is characterized in that; Comprise: LGP, light sources, optical diaphragm group and reflector plate, said light sources are positioned at the side of said LGP and are attached on the liquid crystal panel, and said optical diaphragm group is arranged at said LGP top; Said reflector plate has body, sidewall and invayination; Said body is arranged at said LGP below and covers said LGP, and said sidewall extends upward from said body and forms, and said invayination extends internally and is attached at the edge of said liquid crystal panel from said sidewall.

2. module backlight as claimed in claim 1 is characterized in that said body is attached on the said LGP through double faced adhesive tape or hot-setting adhesive.

3. module backlight as claimed in claim 1 is characterized in that, said invayination is attached at the edge of said liquid crystal panel through double faced adhesive tape or hot-setting adhesive.

4. module backlight as claimed in claim 1 is characterized in that, said light sources is attached at the edge of said liquid crystal panel through double faced adhesive tape or hot-setting adhesive.

5. like any described module backlight in the claim 1 to 4, it is characterized in that said light sources is positioned at a side of said LGP.

6. like any described module backlight in the claim 1 to 4, it is characterized in that said light sources is positioned at the both sides of said LGP.

7. like any described module backlight in the claim 1 to 4, it is characterized in that said optical diaphragm group comprises following diffusion sheet, following brightening piece from the bottom to top, goes up brightening piece and last diffusion sheet.

8. a liquid crystal indicator is characterized in that, comprises liquid crystal panel and like each described module backlight in the claim 1 to 7.

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