CN201401698Y

CN201401698Y - Backlight module

Info

Publication number: CN201401698Y
Application number: CN2009201368443U
Authority: CN
Inventors: 张家骏; 张庆龙
Original assignee: CPTF Visual Display Fuzhou Ltd; Chunghwa Picture Tubes Ltd
Current assignee: CPTF Visual Display Fuzhou Ltd
Priority date: 2009-02-26
Filing date: 2009-02-26
Publication date: 2010-02-10
Anticipated expiration: 2019-02-26

Abstract

The utility model relates to a backlight module which at least comprises a light conducting plate, a luminous unit and a lampshade, wherein the light conducting plate is composed of an upper surface,a lower surface and at least one lateral face, the luminous unit is arranged on the lateral face of the light conducting plate, the lampshade consists of a first holding portion and a second holding portion, wherein the first holding portion is used for clamping the light conducting plate, and the second holding portion is used for clamping the luminous unit. The device can tightly fix the luminous element in the lampshade, is beneficial for the heat radiation of the luminous element, and can improve the service life of the luminous element.

Description

Backlight module

Technical Field

The utility model relates to a backlight module, and in particular to utilize lamp shade closely to be fixed in backlight module of light guide plate one side with luminescence unit.

Technical Field

With the progress of modern video technology, liquid crystal displays have been widely used on the display screens of consumer electronic products such as mobile phones, notebook computers, personal computers and personal digital assistants. However, since the lcd panel of the lcd does not have the function of emitting light, a backlight module is still required to be disposed outside the lcd panel to provide the light source required by the lcd panel, so as to achieve the display effect of the lcd panel.

Generally, a backlight module is composed of a light source, a reflective plate, a light guide plate, an optical film set, and a frame set. The light source used in the backlight module includes a cold cathode fluorescent tube, a hot cathode fluorescent tube, a motor light-emitting sheet or a light-emitting diode, among which the cold cathode fluorescent tube is the most commonly known user. However, in recent years, the led is apparently a member of new light source development. The LED has the advantages of high color, high brightness, no mercury, and high color saturation. Therefore, the use of LED as the backlight module light source can provide higher added value to the LCD panel and provide better visual enjoyment compared with the cold cathode fluorescent tube, so the LED is gradually replacing the cold cathode fluorescent tube.

Referring to FIG. 1, it is an exploded view of the main components of a liquid crystal display 1 using a conventional LED as a backlight module light source. As shown in the figure, the lcd 1 at least includes an lcd panel 11 and a backlight module 12. The backlight module 12 includes a bottom case 121, a reflective plate 122, a light guide plate 123, a plurality of optical films 124, and a plurality of light emitting diodes 125 a. It should be noted that although the light emitting diodes 125a are light sources with low heat energy, the heat generated by the light emission of the plurality of light emitting diodes 125a is considerable. Therefore, in the current manufacturing process, a plurality of leds 125a are usually disposed on an elongated circuit board 125b at intervals to form a linear light source device 125. Furthermore, the linear light source device 125 is disposed on a sidewall of the bottom case 121, and light thereof is guided to the light guide plate 123.

However, the most significant drawback of the lcd using leds as backlight source is that the lifetime (lifetime) of the leds is easily affected by high temperature and is reduced. Therefore, how to reduce the operating temperature of the LED or increase the heat dissipation of the module in the backlight system becomes an important issue.

Referring to FIG. 2, a cross-sectional view of a conventional LCD with LED as the light source of the backlight module is shown. As shown in the figure, the LCD 2 has an LCD panel 21 and a backlight module 22. The backlight module 22 includes a back plate set (not shown), a reflective plate 221, a light guide plate 222, a plurality of optical films 223, a lamp shade 224, and a linear light source device 225 disposed in the lamp shade 224.

The Lamp shade (Lamp cover)224 is an ㄈ -shaped member having an accommodating space, and the upper and lower plates of the ㄈ -shaped member are respectively in contact with the upper and lower surfaces of the light guide plate 222 to clamp the Lamp shade on one side of the light guide plate 222.

The line light source device 225 includes a circuit board 2251 and a plurality of leds 2252, wherein the leds 2252 are disposed on the circuit board 2251 at intervals (not shown). The linear light source device 225 is disposed in the accommodating space of the lampshade 224 and on the lower plate of the lampshade. The circuit board 2251 is parallel to the light exit surface of the light guide plate 222, and the light emitting surface of the led 2252 is parallel to the light entrance side of the light guide plate 222.

Generally, there are two ways to fix the circuit board 2251 to the lamp housing 224. Referring to fig. 3 and 4, cross-sectional views of an embodiment and another embodiment of a linear light source device fixed in a lamp housing are shown. As shown in fig. 3, a Double coated tape 3(Double coated tape) is used to adhere the circuit board 2251 and the lamp housing 224, however, this method has a disadvantage in that the thermal resistance at the contact surface is increased.

In the second fixing method, as shown in fig. 4, two ends of the single-sided tape 4 are respectively adhered to one end of the circuit board 2251 and the lamp housing 224. However, this method cannot make the circuit board 2251 and the lampshade 224 tightly attached, and the thermal resistance is also increased at the interface between the circuit board 2251 and the lampshade 224 when the tape 4 is attached. If the thermal resistance increases in the path of heat conduction, the efficiency of heat conduction from LED 2252 to the lamp housing 22 is also reduced, resulting in a shorter LED lifetime.

Disclosure of Invention

The utility model aims at providing a backlight module, the device not only can make light emitting component closely be fixed in the lamp shade, is favorable to light emitting component's heat dissipation moreover to improve light emitting component's life.

The technical scheme of the utility model is realized like this: it at least comprises a light guide plate, which has an upper surface, a lower surface and at least one side surface; a light emitting unit disposed on one side of the light guide plate; and a lampshade having a first clamping part and a second clamping part, wherein the first clamping part is used for clamping the light emitting unit, and the second clamping part is used for clamping the light guide plate.

The utility model has the advantages of reasonable design, simple structure, because its light emitting component is great with the lamp shade contact surface, so not only can make in light emitting component closely is fixed in the lamp shade, be favorable to light emitting component's heat dissipation moreover, can improve light emitting component's life.

In order to make the aforementioned and other features and advantages of the invention more comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

FIG. 1 is an exploded view of a conventional LED applied to a backlight module of a liquid crystal display;

FIG. 2 is a cross-sectional view of a conventional LCD with LEDs as the light source of the backlight module;

FIG. 3 is a schematic cross-sectional view illustrating an embodiment of a conventional linear light source device fixed in a lamp housing;

FIG. 4 is a schematic cross-sectional view of another embodiment of a linear light source device fixed in a lamp housing;

fig. 5 is a schematic view illustrating a backlight module according to an embodiment of the invention.

[ description of main reference symbols ]

1. 2 liquid crystal display

11 liquid crystal display panel

12 backlight module

121 bottom box

122 reflecting plate

123 light guide plate

124 optical film

125 linear light source device

125a light emitting diode

125b circuit board

21 liquid crystal display panel

22 backlight module

221 reflecting plate

222 light guide plate

223 optical film

224 lampshade

225 light emitting unit

2251 Circuit Board

2252 light source

3 double-sided adhesive tape

4 Single-sided adhesive tape

52 backlight module

521 reflecting plate

522 light guide plate

522a upper surface

522b lower surface

522c side surface

523 optical diaphragm

524 lampshade

5241 side wall

5242 first plate

5242a first plane

5242b second plane

5243A second plate

524a first clamping part

524b second clamping part

525 luminous unit

5251 Circuit Board

5252 light source

Detailed Description

The following description will further explain embodiments of the present invention with reference to the accompanying drawings.

Referring to fig. 5, a schematic diagram of a backlight module according to an embodiment of the invention is shown. As shown, the backlight module 52 at least includes a back plate set (not shown), a reflective plate 521, a light guide plate 522, a plurality of optical films 523, a lamp cover 524, and a light emitting unit 525 disposed in the lamp cover 524.

The light guide plate 522 has an upper surface 522a, a lower surface 522b and at least one side surface 522 c.

The light emitting unit 525 is disposed on the side surface 522c of the light guide plate 522. The light emitting unit 525 includes a circuit board 5251 and a plurality of light sources 5252, wherein the light sources 5252 are disposed on one surface of the circuit board 5251 in a linear arrangement (not shown) and electrically connected thereto. In a preferred embodiment, the Light source 5252 is a Light emitting diode (led) and is fixed on the circuit board 5251 by Surface Mount Technology (SMT).

The lampshade 524 has a first clamping portion 524a and a second clamping portion 524b, wherein the first clamping portion 524a is used for clamping the light emitting unit 525, and the second clamping portion 524b is used for clamping the light guide plate 522. In a preferred embodiment, the lampshade has a side wall 5241 and a first plate 5242 and a second plate 5243 connected to the upper and lower ends thereof, and the two

plates

5242, 5243 extend in the same direction to form an accommodating space.

The light emitting unit 525 is disposed in the accommodating space of the lampshade 524. The circuit board 5251 is connected to the second plate 5243 of the lampshade 524 through the other surface thereof. The light source 5252 has a light emitting surface perpendicular to the circuit board 5251 and facing the side surface 522c of the light guide plate 522.

With continued reference to fig. 5, the structure of lampshade 524 is further illustrated: wherein,

the first plate 5242 includes a first plane 5242a and a second plane 5242b, the second plane 5242b is generated by the first plate 5242 being recessed toward the accommodating space of the lampshade 524, and an

inclined plane

5242a and 5242b is formed therebetween.

It is particularly noted that the first holding portion 524a is formed by the second plane 5242b of the first plate 5242 of the lampshade 524 and the second plate 5243, and the second plane 5242b is in contact with the light sources to hold the light emitting unit 525 by the first holding portion 524 a. In the preferred embodiment, the lampshade 524 is made of a metal material, which can increase the heat dissipation effect of the light emitting unit 525.

In addition, the second holding portion 524b is formed by the first plane 5242a and the second plate 5243 of the first plate 5242 of the lampshade 524, and the first plane 5242a contacts with the upper surface 522a of the light guide plate 522 to hold the light guide plate 522 by the second holding portion 524 b.

It is further proposed that, as shown in the figure, the length of the first plate of the lamp housing is smaller than the length of the second plate. As mentioned above, the backlight module 52 of the present invention further includes the reflective plate 521 disposed on the lower surface 522b of the light guide plate 522, and a portion of the reflective plate 521 is adjacent to the circuit board 5251 of the light emitting unit 525 and is disposed on the second plate 5243 of the lamp housing 524.

To sum up, the present invention can effectively fix the light emitting unit 525 to the side 522c of the light guide plate 522 by using the first clamping portion 524a and the second clamping portion 524b of the lampshade 524, and can further increase the heat dissipation effect of the light emitting unit 525 by contacting the second plane 5242b on the first plate 5242 of the lampshade 524 with the light emitting unit 525.

Although the present invention has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A backlight module is characterized by at least comprising:

a light guide plate having an upper surface, a lower surface and at least one side surface;

a light emitting unit disposed on one side of the light guide plate; and

the lamp shade is provided with a first clamping part and a second clamping part, wherein the first clamping part is used for clamping the light-emitting unit, and the second clamping part is used for clamping the light guide plate.

2. A backlight module according to claim 1, wherein: the lampshade is provided with a side wall, a first plate and a second plate, wherein the upper end and the lower end of the side wall are connected with each other, the extending directions of the two plates are the same so as to form an accommodating space, and the light-emitting unit is arranged in the accommodating space of the lampshade.

3. A backlight module according to claim 2, wherein: the first plate comprises a first plane and a second plane, the second plane is generated by the first plate sinking towards the accommodating space of the lampshade, and an inclined plane is arranged between the two planes.

4. A backlight module according to claim 3, wherein: the light-emitting unit is provided with a circuit board and a plurality of light sources, and the light sources are arranged on one surface of the circuit board in a linear arrangement mode and are electrically connected with the circuit board.

5. The backlight module according to claim 4, wherein: the first clamping part is composed of the second plane of the lampshade and the second plate, and the second plane is contacted with the light sources to enable the first clamping part to clamp the light-emitting unit.

6. A backlight module according to claim 3, wherein: the second clamping part is composed of the first plane of the lampshade and the second plate, and the first plane is contacted with the upper surface of the light guide plate to enable the second clamping part to clamp the light guide plate.

7. The backlight module according to claim 4, wherein: the circuit board is connected with the second plate of the lampshade by the other surface of the circuit board.

8. The backlight module according to claim 4, wherein: the light source is provided with a light emitting surface which is vertical to the circuit board and is opposite to the side surface of the light guide plate, and the light source is a light emitting diode.

9. A backlight module according to claim 2, wherein: the lamp shade further comprises a reflecting sheet arranged between the second plate of the lamp shade and the lower surface of the light guide plate.

10. A backlight module according to claim 1, wherein: the lampshade is made of a metal material.