TWI400532B - Backlight module and liquid crystal display device including the same - Google Patents

Description

Backlight module and liquid crystal display device using the same

The present invention relates to a backlight module and an application thereof, and more particularly to a backlight module having a heat dissipation structure and its application to a liquid crystal display device.

Liquid crystal displays are currently evolving toward thinner, thereby increasing space utilization. At the same time, as the earth's natural energy is gradually depleted, liquid crystal displays are also designed to emphasize energy conservation. In a liquid crystal display, a backlight module is one of the main energy consuming components. In order to achieve energy-saving effects, more and more backlight modules have been replaced with Light Emitting Diodes (LEDs) to replace the traditional Cold Cathode Fluorescent Lamps (CCFLs). In addition to the energy-saving effect, the light-emitting diode can also meet the needs of thinning. In addition, another advantage of the light-emitting diode compared to a cold cathode lamp is that it does not contain a mercury component that is prone to permanent environmental pollution.

Referring to FIG. 3, in a backlight module generally using a light-emitting diode as a light source, the backlight module includes a back plate 402, a frame structure (not shown), a light guide plate (not shown), and a plurality of light-emitting layers. A light bar 404 of the diode 404a and a light bar mount 406. The light emitting diode 404a in the backlight module is soldered to a printed circuit board (PCB) 404b to form a light strip 404. The light bar 404 is then joined to the light bar mount 406. After the above steps are completed, the light bar holder 406 is joined to the heat dissipation fins 408 by screws 410 and screw holes 412. Next, the heat dissipation fins 408 are also bonded to the back plate 402 by the screws 410 and the screw holes 412, so that the plurality of light emitting diodes 404a are adjacent to the incident surface of the light guide plate. Finally, the frame structure is bonded to the backplane 402 to complete the assembly of the backlight module. In the above backlight module, the frame structure is generally composed of a plurality of frames (not shown). In the assembly process of the backlight module, a part of the frame body is first joined to the back plate. The other components described above are accommodated, and the assembly of the backlight module is completed by bonding the last frame to the backplane.

In a general design, the heat dissipating fins 408 are disposed to meet the heat dissipation requirements of the LEDs 404a. In order to enhance the heat dissipation capability of the light bar 404, heat conductive materials 414 and 416 are usually added between the light bar 404 and the light bar fixing seat 406, and between the light bar fixing seat 406 and the heat dissipation fin 408, wherein the heat conductive materials 414 and 416 are further It acts as an adhesive to bond the two components together more firmly. In addition, in order to enhance the heat dissipation capability of the light bar, the light bar fixing seat 406, the heat dissipation fin 408 and the back plate 402 are generally made of a metal material.

However, the conventional design of the backlight module has the disadvantage that the assembly process is complicated.

Therefore, the object of the present invention is to provide a backlight module and a liquid crystal display device using the same, wherein the backlight module has a heat dissipation structure, and the design thereof can reduce the structural complexity, thereby achieving the purpose of simplifying the assembly process.

According to an embodiment of the invention, a backlight module is provided. The backlight module with a heat dissipation structure comprises a back plate, a frame structure joined to the back plate, a light guide plate and a plurality of light emitting diodes. The frame structure and the backboard define an accommodating space for arranging the light guide plate, and the frame structure comprises a first frame body and at least one second frame body joined to the first frame body. The first frame body has a first side surface facing the accommodating space, wherein the first frame body is provided with a plurality of heat dissipation fins on other surface portions other than the first side surface. The plurality of light emitting diodes are electrically connected to the first side of the first frame and adjacent to a second side of the light guide plate.

According to another embodiment of the present invention, a liquid crystal display device is provided. The liquid crystal display device comprises a liquid crystal display module and a backlight module, wherein the backlight module is disposed on the back of the liquid crystal display module. The backlight module includes a back plate, a frame structure joined to the back plate, a light guide plate, and a plurality of light emitting diodes. The frame structure and the backboard define an accommodating space for arranging the light guide plate, and the frame structure comprises a first frame body and at least one second frame body joined to the first frame body. The first frame body has a first side surface facing the accommodating space, wherein the first frame body is provided with a plurality of heat dissipation fins on other surface portions other than the first side surface. The plurality of light emitting diodes are electrically connected to the first side of the first frame and adjacent to a second side of the light guide plate.

The invention has the advantages that, by directly bonding the LEDs to the frame structure, in addition to simplifying the assembly process and improving the production efficiency, the number of backlight module components can be reduced, and the material cost can be reduced. expenditure. In addition, since the frame structure is in contact with the air outside the backlight module, the light-emitting diode is directly bonded to the frame structure to have a fast heat dissipation effect. Furthermore, compared with the generally designed light strip fixing seat, the light emitting diode is disposed on the frame body with the heat dissipating fins, and has better anti-twisting strength.

Referring to FIG. 1, there is shown a side view of a liquid crystal display device according to an embodiment of the present invention. In the present embodiment, the liquid crystal display device 100 is composed of a liquid crystal display module 200 and a backlight module 300 having a heat dissipation structure. The backlight module 300 is an edge lighting backlight module, and the backlight module 300 is disposed relative to the liquid crystal display module 200, that is, the liquid crystal display module 200 is disposed on the backlight module 300.

2A and 2B, wherein FIG. 2A is a schematic plan view of the backlight module in FIG. 1 and FIG. 2B is a cross-sectional view taken along line AA' in FIG. 2A. The backlight module 300 includes a back plate 302 (shown in FIG. 2B), a frame structure 304, a light guide plate 306, and a plurality of light emitting diodes 308, wherein the frame structure 304 and the back plate 302 are joined to each other. In the present embodiment, the frame structure 304 includes a first frame 304a and at least a second frame 304b, wherein the second frame 304b is joined to the first frame 304a to form a rectangular structure as shown in FIG. 2A.

In the embodiment shown in Figures 2A and 2B, the second frame 304b is composed of three sub-frames 304ba, 304bb and 304bc (as shown in Figure 2A). The three sub-frames 304ba, 304bb, and 304bc constituting the second frame 304b are sequentially joined to the first frame 304a, and each of the sub-frames 304ba, 304bb, and 304bc has substantially the same as the first frame 304a. Profile structure (as shown in Figure 2B). However, the number and geometry of the sub-frames constituting the second frame 304b of the backlight module are not limited to the three of the embodiments, and the number and shape thereof can be adjusted according to the geometry of the backlight module. In a specific embodiment, the second frame may also be an integrally formed frame, which is not limited to the structure shown in FIGS. 2A and 2B, that is, not limited to three sub-frames 304ba, 304bb, and 304bc. The second frame body 304b is combined to form. Moreover, in a particular embodiment, the cross-sectional structure of the secondary frame forming the second frame is different from the cross-sectional structure of the first frame.

In the embodiment shown in FIGS. 2A and 2B, the rectangular frame structure 304 is bonded to the backing plate 302, and the backing plate 302 defines an accommodating space 310 (as shown in FIG. 2B), wherein the accommodating space 310 is The main function is to set the light guide plate 306.

The first frame body 304a has a side surface 304c facing the accommodating space 310 for arranging a plurality of light emitting diodes 308 such that the plurality of light emitting diodes 308 are disposed adjacent to the side surface 306a of the light guide plate 306 (as shown in FIG. 2B). ). The side surface 306a of the light guide plate 306 is also the incident surface, and the light generated by the plurality of light-emitting diodes 308 enters the light guide plate 306 from the side surface 306a. After being diffused a plurality of times, the light is emitted through the light-emitting surface 306b (as shown in FIG. 2B). . Before the plurality of light-emitting diodes 308 are disposed on the side surface 304c of the first frame body 304a, the plurality of light-emitting diodes 308 are usually electrically connected to form a light-emitting diode light bar.

In order to exclude waste heat generated by the plurality of light emitting diodes 308, the first frame body 304a is provided with heat radiating fins 304d at a surface portion with respect to the first side surface 304c. The arrangement position of the heat dissipating fins 304d is not limited to the embodiment. In the first frame body 304a, in addition to the first side surface 304c, it is required to be used as the light emitting diode 308, and the first frame body 304a remains. Heat sink fins 304d may be disposed on the surface. In addition, the number of heat dissipation fins 304d can be adjusted according to the amount of waste heat generated by the plurality of light emitting diodes 308.

Since the plurality of light emitting diodes 308 are directly bonded to the first side surface 304c of the first frame body 304a, and the heat dissipation fins 304d are located on the surface of the first frame body 304a relative to the first side surface 304c, After the waste heat generated by the light-emitting diode 308 is transmitted to the heat-dissipating fins 304d, the waste air can be removed by the cold air in the open space to achieve rapid heat dissipation.

In addition, as shown in FIG. 2A, in the embodiment, the second frame 304b of the second frame 304b is also provided with a plurality of light emitting diodes 308 on the side of the light guide plate 306, thereby adding the backlight module 300. The overall brightness value. In a specific embodiment, when the brightness requirement of the backlight module 300 is low, the plurality of light emitting diodes 308 may be disposed only on the side surface 304c of the first frame 304a. In order to remove the waste heat generated by the plurality of light-emitting diodes 308 disposed on the sub-frame 304bb, the heat-dissipating fins 304d as shown in FIG. 2B are also disposed on the sub-frame 304bb.

Please refer to Figure 2B again. The first frame 304a and the second frame 304b of the frame structure 304 and the back plate 302 respectively include a screw hole 314. The frame structure 304 and the back plate 302 are mutually matched by the screw 312 and the screw hole 314. Engage. The frame structure 304 and the back plate 302 can be joined to each other by other engaging structures (for example, a fastening structure, an adhesive, or a combination thereof) in addition to the above-mentioned screws 312 and the screw holes 314. Since the joint structure of the frame structure and the back plate belongs to the technical features commonly used in the technical field, it will not be described in detail.

Further, in the present embodiment, the first frame body 304a is integrally formed with the frame body. The advantage of this design is that the waste heat generated by the LED 308 can be transmitted to the heat dissipation fins 304d without passing through the conventional light bar holder, thereby increasing the efficiency of heat dissipation. In a particular embodiment, the integrally formed first frame 304a is an aluminum extruded frame. In order to provide heat dissipation, the first frame 304a is fabricated from a material having good heat transfer characteristics. In a particular embodiment, the material of the first frame 304a is a metallic material, such as the aluminum described above.

In addition, the light-emitting diode 308 is bonded to the first frame body 304a having the heat-dissipating fins, and the light-emitting diode 308 is preferably bonded to the flat-shaped light-strip fixing base. Resistance to twisting.

Please refer to FIG. 4, which is a cross-sectional view of a backlight module according to another embodiment of the present invention. In the present embodiment, the structure of the backlight module 500 is similar to that shown in FIG. 2B, and thus the relationship between similar structures or elements, and similar structures or elements will not be described. Hereinafter, only the difference between the backlight module 500 and the backlight module 300 shown in FIG. 2B will be described. In the backlight module 300, the first frame 304a and the second frame 304b of the rectangular frame structure 304 are fastened on the back plate 302, and the frame structure 304 is joined to the back plate 302 by screws 312, thereby defining The space 310 is accommodated as shown in FIG. 2B. In the backlight module 500 shown in FIG. 4, the first frame 504a and the second frame 504b corresponding to the first frame 304a and the second frame 304b of the backlight module 300 respectively extend to the back plate. The bottom surface of the 502, that is, the back plate 502 is positioned on the first frame 504a and the second frame 504b, and the back plate 502, the first frame 504a and the second frame 504b are joined to each other by screws 312.

In a specific embodiment, the light guide plate is formed into a flat plate structure or a wedge plate structure by, for example, injection molding, and the material thereof is, for example, a photocurable resin, acryl or polymethyl methacrylate (PMMA).

In addition, in a specific embodiment, the backlight module 300 further includes at least one optical film (not shown), and the optical film is disposed on the light guide plate, and the optical film may be a diffusion sheet. A film, a brightness enhancement film (BEF), a dual brightness enhancement film (DBEF), a non-multilayer film reflective polarizer (DRPF), or any combination thereof.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

100. . . Liquid crystal display device

200. . . Liquid crystal display module

300. . . Backlight module

302. . . Backplane

304. . . Framework

304a. . . First frame

304b. . . Second frame

304ba. . . Secondary frame

304bb. . . Secondary frame

304bc. . . Secondary frame

304c. . . side

304d. . . Heat sink fin

306. . . Light guide

306a. . . side

306b. . . Glossy surface

308. . . Light-emitting diode

310. . . Housing space

312. . . Screw

314. . . Screw hole

402. . . Backplane

404. . . Light

404a. . . Light-emitting diode

404b. . . A printed circuit board

406. . . Light bar mount

408. . . Heat sink fin

410. . . Screw

412. . . Screw hole

414. . . Heat conductive material

416. . . Heat conductive material

500. . . Backlight module

502. . . Backplane

504a. . . First frame

504b. . . Second frame

504c. . . side

AA’. . . Section line

For a better understanding of the present invention, reference is made to the above detailed description and the accompanying drawings. It is emphasized that, in accordance with the standard of the industry, the various features in the drawings are not to scale. In fact, the dimensions of the various features may be arbitrarily enlarged or reduced in order to clearly illustrate the above embodiments. The relevant schema description is as follows.

Fig. 1 is a side view showing a liquid crystal display device according to an embodiment of the present invention.

FIG. 2A is a schematic plan view showing the backlight module in FIG. 1 .

Fig. 2B is a schematic cross-sectional view taken along line AA' of Fig. 2A.

FIG. 3 is a cross-sectional view showing a part of a conventional backlight module.

4 is a cross-sectional view showing a backlight module according to another embodiment of the present invention.

300. . . Backlight module

302. . . Backplane

304a. . . First frame

304b. . . Second frame

304bb. . . Secondary frame

304c. . . side

304d. . . Heat sink fin

306. . . Light guide

306a. . . side

306b. . . Glossy surface

308. . . Light-emitting diode

310. . . Housing space

312. . . Screw

314. . . Screw hole

Claims (10)

A backlight module includes: a back plate; a frame structure engaged with the back plate, wherein the frame structure and the back plate define an accommodating space, and the frame structure comprises: a first frame having a face a first side of the accommodating space, wherein the first frame body is provided with a plurality of heat dissipating fins on other surface portions other than the first side surface; and at least one second frame body is engaged with the first frame body a light guide plate disposed in the accommodating space; and a plurality of light emitting diodes electrically connected to the first side of the first frame body, wherein the light emitting diode systems are adjacent to the light emitting diode a second side of the light guide plate, wherein the light emitting diodes directly engage the first side of the first frame. The backlight module of claim 1, wherein the material of the first frame is a metal material. The backlight module of claim 1, wherein the first frame system integrally forms a frame. The backlight module of claim 3, wherein the first frame system is an aluminum extruded frame. The backlight module of claim 1, wherein the second frame system is composed of three frames, and the second frames are sequentially engaged with the first frame. The backlight module of claim 1, wherein the first frame body, the second frame body and the back plate of the frame structure further comprise an engaging structure selected from the group consisting of a screw and a screw hole. A combination of a carding structure, a glue, and a combination of the above. A liquid crystal display device comprising: a liquid crystal display module; and a backlight module disposed on the back of the liquid crystal display module, comprising: a back plate; a frame structure engaged with the back plate, wherein the frame structure and The backplane defines an accommodating space, and the frame structure comprises: a first frame having a first side facing the accommodating space, wherein the first frame is outside the first side The portion is provided with a plurality of heat dissipation fins; and at least one second frame body is engaged with the first frame body; a light guide plate is disposed in the accommodating space; and a plurality of light emitting diodes are electrically connected On the first side of the first frame, the light emitting diodes are disposed adjacent to a second side of the light guide plate, wherein the light emitting diodes directly engage the first side of the first frame side. The liquid crystal display device of claim 7, wherein the material of the first frame of the backlight module is a metal material. The liquid crystal display device of claim 7, wherein the first frame system of the backlight module integrally forms a frame, and the first frame is an aluminum extruded frame. The liquid crystal display device of claim 7, wherein the second frame system of the backlight module is composed of a tertiary frame, and the secondary frames are sequentially engaged with the first frame.