TW201400944A - Back light module and liquid crystal display device - Google Patents

Abstract

The present invention discloses a backlight module and a display device using the same. The backlight module includes a light guide plate and a frame accommodating the light guide plate. The light guide plate includes a light emitting surface, a bottom surface opposite to the light emitting surface, and a plurality of side surfaces. A size of the bottom surface is greater than a size of the light emitting surface to allow the bottom surface to connect to at least one corresponding side surface to protrude out from the light emitting surface connected to the at least one corresponding side surface. The light emitting surface defines a cutout at where the light emitting surface connected to the at least one corresponding side surface. The cutout passes through the at least one corresponding side surface along a length direction of the corresponding at least one side surface. The frame includes at least one protrusion, and the protrusion matches with the cutout to fix the light guide plate.

Description

Backlight module and liquid crystal display device

The invention relates to a backlight module and a liquid crystal display device using the same.

Since the liquid crystal in the liquid crystal display panel itself has no light-emitting characteristics, in order to achieve the display effect, it is necessary to provide a light source device for the liquid crystal display panel to realize a display function, such as a backlight module, and the function thereof is to provide sufficient brightness and uniform distribution to the liquid crystal display panel. Surface light source.

Generally, the backlight module mainly includes a light source, a light guide plate and a frame. The light source is disposed opposite to the light incident surface of the light guide plate, and the light guide plate guides the transmission direction of the light beam emitted from the light source, and converts the light beam emitted by the line light source or the point light source into a relatively uniform plane light to emit the liquid crystal display panel in the liquid crystal display, the frame The component for fixing the backlight module. The light guide plate and the frame of the backlight module are conventionally used by the protrusions on the light guide plate and the card slots on the frame to cooperate with each other. However, due to the positioning manner of the light guide plate protrusions, the thickness of the frame on the frame is larger than the card. The thickness of the groove leads to an increase in the thickness of the frame, thereby increasing the thickness of the backlight module, which is disadvantageous for the development of thinning of the display device.

In view of this, it is necessary to provide a backlight module that can reduce the thickness of the backlight module.

In view of this, it is also necessary to provide a liquid crystal display device which can reduce the thickness of the backlight module.

A backlight module includes a light guide plate and a frame for receiving the light guide plate. The light guide plate is disposed in the frame, and includes a light emitting surface, a bottom surface opposite to the light emitting surface, and a plurality of side surfaces intersecting the light emitting surface and the bottom surface. The bottom surface has a size larger than the size of the light-emitting surface such that the bottom surface connected to the at least one side surface protrudes from the light-emitting surface of the at least one side surface, and defines a notch on a light-emitting surface side of the light guide plate. The notch extends along the length of the at least one side surface and extends through the at least one side, and the frame includes at least one protrusion that matches the notch for positioning the light guide plate.

A liquid crystal display device includes a liquid crystal panel and a backlight module disposed adjacent to the liquid crystal panel. The backlight module includes a light guide plate and a frame for receiving the light guide plate. The light guide plate is disposed in the frame, and includes a light emitting surface, a bottom surface opposite to the light emitting surface, and a plurality of side surfaces intersecting the light emitting surface and the bottom surface. The bottom surface has a size larger than the size of the light-emitting surface such that the bottom surface connected to the at least one side surface protrudes from the light-emitting surface of the at least one side surface, and defines a notch on a light-emitting surface side of the light guide plate. The notch extends along the length of the at least one side surface and extends through the at least one side, and the frame includes at least one protrusion that matches the notch for positioning the light guide plate.

Since the light guide plate eliminates the protrusion design on the side surface, the protrusion design of the frame is inserted into the notch of the side surface of the light guide plate, thereby reducing the thickness of the frame and facilitating the thinning development of the backlight module.

Please refer to FIG. 1, which is a schematic view of a first embodiment of a liquid crystal display device of the present invention. The liquid crystal display device 1 includes an upper cover 10, a liquid crystal panel 20, and a backlight module 40 disposed adjacent to the liquid crystal panel 20. The backlight module 40 includes an optical film set 420, a light guide plate 430, a light source 440, a reflective sheet 460, a frame 450, and a backing plate 480. The upper cover 10 cooperates with the back plate 480 to receive the liquid crystal panel 20 and the backlight module 40 therein.

The light guide plate 430 includes a light exit surface 431 , a bottom surface 432 opposite to the light exit surface 431 , a plurality of side surfaces 434 connecting the light exit surface 431 and the bottom surface 432 , and at least one notch 436 . The bottom surface 432 of the light guide plate 430 has a size larger than the size of the light exit surface 431, such that the bottom surface 432 connected to the at least one side surface 434 protrudes from the light exit surface 431 to which the at least one side surface 434 is connected, and the at least one side surface 434 is lighted out. The face 431 side defines the at least one notch 436. The at least one notch 436 extends along the length of the at least one side 434, and the extended length of the at least one notch 436 preferably coincides with the length of the at least one side 434 to extend through the entire side 434. The thickness of the light guide plate 430 at the notch 436 is smaller than the thickness of the other portion of the light guide plate 430, that is, the thickness of the notch 436 in the direction perpendicular to the light exit surface 431 is smaller than the thickness of the light exit surface 431 of the light guide plate 430 from the bottom surface 432. In this embodiment, the number of the at least one side surface 434 is two, and the two side surfaces 434 are oppositely disposed. The gap 436 is a triangular notch. In this embodiment, the two opposite sides 434 defining the notch 436 can be formed by cutting a corner of the light-emitting surface 431 of the light guide plate 431 and having a triangular cross-section, and on the corresponding side 434 and the light-emitting surface 431. A face 439 is formed between the face 439 and the corresponding face 434.

The optical film set 420 includes an upper diffusion sheet 421, an upper brightness enhancement sheet 422, a lower brightness enhancement sheet 423 and a lower diffusion sheet 424. The lower diffusion sheet 424, the lower brightness enhancement sheet 423, the upper brightness enhancement sheet 422 and the upper diffusion sheet 421 are The bottom to top is disposed adjacent to the light exit surface 431 in this order. The reflective sheet 460 is disposed adjacent to the bottom surface 432.

The light source 440 can be selected as a plurality of light emitting diodes.

The frame 450 includes a plurality of grooves 452 and oppositely disposed two protrusions 456 that match the oppositely disposed two notches 436 of the light guide plate 430. In this embodiment, the protrusion 456 is a triangular protrusion, and the triangular protrusion has a slope 4561 facing the section 439 of the notch 436, and the slope 4561 is for abutting the section 439. The length of the protrusion 456 is the same as the length of the side surface 434 of the light guide plate 430. The light guide plate 430 is received in the frame 450 by the engagement of the notch 436 and the protrusion 456 and is positioned. The plurality of grooves 452 are for receiving the plurality of light emitting diodes.

2 and FIG. 3, FIG. 2 is a schematic view showing the assembly of the backlight module of the liquid crystal display device shown in FIG. 1, and FIG. 3 is a cross-sectional view of FIG. 2 taken along the line III-III. During assembly, the light guide plate 430 is received in the frame 450 such that the inclined surface 4561 of the protrusion 456 on the frame 450 abuts the cut surface 439 of the notch 436 of the light guide plate 430 to make the gap 436 of the light guide plate 430 and the frame 450 The protrusions 456 are matched to realize the positioning of the light guide plate 430. The plurality of light emitting diodes are received in the plurality of grooves 452 of the frame 450. The reflection sheet 460 is disposed adjacent to the bottom surface 432 of the light guide plate 430. The optical film is disposed. The group 420 is disposed adjacent to the light exit surface 431 of the light guide plate 430. The backboard 480 houses other components of the backlight module 40 described above.

Since the light guide plate 430 cancels the protrusion design on the side surface 434, it utilizes the cooperation of the notch design of the side surface 434 of the light guide plate 430 and the protrusion 456 of the frame 450 to position the light guide plate 430, so that it is not necessary to increase the size of the frame 450, thereby Reducing the thickness of the frame 450 facilitates the thinning development of the backlight module 40.

And because the notch 436 of the side 434 of the light guide plate 430 penetrates the corresponding side 434 in the direction of the length of the corresponding side 434, the length of the frame 450 protrusion 456 matching the notch 436 is the same as the length of the side 434 of the light guide plate 430. Therefore, the protrusion 456 can simultaneously strengthen the strength of the frame 450 to support, so that the position of the light guide plate 430 with the side surface 434 of the notch 436 can be further reduced in design when the overall size is constant. The frame 450 has a thickness D1 such that the position of the side surface 434 of the light guide plate 430 having the notch 436 in contact with the frame 450 is increased from the distance D2 between the gap 436 of the light guide plate 430 and the light exit surface 431, and thus, when the user is guided When the side of the light-emitting surface 431 of the light plate 430 is viewed from the inside, it is difficult to see the gap between the light guide plate 430 and the frame 450, and the line defect at the time of side view is largely avoided.

Please refer to FIG. 4, which is a schematic view of a second embodiment of the liquid crystal display device of the present invention. The difference between the liquid crystal display device of the second embodiment of the present invention and the liquid crystal display device 1 of the first embodiment is that the thickness of the notch 536 of the light guide plate 530 in the direction perpendicular to the light exit surface 531 is equal to the light exit surface of the light guide plate 430. The thickness of the bottom surface 532 is 431 such that the cut surface 539 of the notch 536 intersects the light exit surface 531 and the bottom surface 532 of the light guide plate 530.

Of course, the present invention is not limited to the preferred embodiment disclosed above. For example, the shape of the notch of the light guide plate of the present invention is not limited to a plane, and accordingly, the shape of the slope of the protrusion is not limited to a plane. The portion of the light guide plate of the present invention which is cut at the light-emitting surface is not limited to a triangle, and may be designed according to a shape change such as a rectangle (see FIG. 5), a trapezoid or the like, and the protrusion shape of the frame matches the notch.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims.

1. . . Liquid crystal display device

10. . . Upper cover

20. . . LCD panel

40. . . Backlight module

420. . . Optical film set

421. . . Upper diffuser

422. . . Adding light

423. . . Lower gloss

424. . . Lower diffuser

430, 530. . . Light guide

431, 531. . . Glossy surface

432, 532. . . Bottom

434, 534. . . side

436, 536. . . gap

439, 539. . . section

440. . . light source

450. . . frame

452. . . Groove

456. . . Protrusion

4561. . . Bevel

460. . . A reflective sheet

480. . . Backplane

1 is a schematic view of a first embodiment of a liquid crystal display device of the present invention.

2 is a schematic view showing the assembly of a backlight module of the liquid crystal display device shown in FIG. 1.

Figure 3 is a cross-sectional view of Figure 2 taken along the line III-III.

Fig. 4 is a schematic view showing a second embodiment of the liquid crystal display device of the present invention.

FIG. 5 is a schematic view showing another modified embodiment of the backlight module of the liquid crystal display device of the present invention.

530. . . Light guide

531. . . Glossy surface

532. . . Bottom

536. . . gap

539. . . section

Claims (12)

A backlight module includes a light guide plate and a frame for accommodating the light guide plate. The light guide plate is disposed in the frame, and includes a light emitting surface, a bottom surface opposite to the light emitting surface, and a surface intersecting the light emitting surface and the bottom surface. a plurality of sides, wherein the size of the bottom surface is larger than the size of the light-emitting surface such that the bottom surface connected to the at least one side protrudes from the light-emitting surface of the at least one side surface, and defines a notch on a side of the light-emitting surface of the light guide plate. The notch extends along the length of the at least one side and extends through the at least one side, and the frame includes at least one protrusion that matches the notch for positioning the light guide plate. The backlight module of claim 1, wherein the thickness of the notch in the direction perpendicular to the light exiting surface is smaller than the thickness of the light emitting surface of the light guide plate from the bottom surface. The backlight module of claim 1, wherein the notch is a triangular cut angle formed by the light guide plate cutting a triangular portion at an edge of the light exiting surface, and the protrusion is a triangular protrusion. The backlight module of claim 3, wherein the thickness of the notch in the direction perpendicular to the light exiting surface is equal to the thickness of the light emitting surface of the light guide plate from the bottom surface. The backlight module of claim 1, wherein the number of the at least one side is two, and the two sides are oppositely disposed, and the length of the protrusion matching the notch and the light guide plate are notched The sides are the same length. The backlight module of claim 1, wherein the backlight module further comprises a backplane, wherein the light guide panel and the frame are received in the backplane, and a bottom surface of the light guide panel is disposed adjacent to the backplane. A liquid crystal display device includes a liquid crystal panel and a backlight module disposed adjacent to the liquid crystal panel. The backlight module includes a light guide plate and a frame for receiving the light guide plate. The light guide plate is disposed in the frame and includes a light emitting surface. a bottom surface opposite to the light emitting surface, a plurality of side surfaces intersecting the light emitting surface and the bottom surface, wherein a size of the bottom surface is larger than a size of the light emitting surface such that a bottom surface connected to the at least one side surface protrudes from the at least one side surface a light-emitting surface defines a notch on a side of the light-emitting surface of the light guide plate, the notch extends along a length direction of the at least one side surface and penetrates the at least one side surface, the frame includes at least one protrusion, and the protrusion is matched with the notch To position the light guide plate. The liquid crystal display device of claim 7, wherein the thickness of the notch in the direction perpendicular to the light exiting surface is smaller than the thickness of the light emitting surface of the light guide plate from the bottom surface. The liquid crystal display device of claim 6, wherein the notch is a triangular chamfer formed by cutting a triangular portion of the light guide plate at an edge of the light exiting surface, and the protrusion is a triangular protrusion. The liquid crystal display device of claim 7, wherein the thickness of the notch in the direction perpendicular to the light exiting surface is equal to the thickness of the light emitting surface of the light guide plate from the bottom surface. The liquid crystal display device of claim 7, wherein the number of the at least one side is two, and the two sides are oppositely disposed, and the length of the protrusion matching the notch and the light guide plate are notched The sides are the same length. The liquid crystal display device of claim 7, wherein the backlight module further comprises a back plate, the light guide plate and the frame are received in the back plate, and a bottom surface of the light guide plate is disposed adjacent to the back plate.