KR100661658B1 - Liquid crystal display - Google Patents

Abstract

The present invention relates to a liquid crystal display device, comprising: a liquid crystal panel on which an image is formed; A backlight unit disposed behind the liquid crystal panel to supply light to the liquid crystal panel; A bottom chassis accommodating the backlight; And a heat pipe for dissipating heat from the backlight unit to the outside of the bottom chassis.

As a result, heat generated in the backlight unit can be efficiently discharged to the outside.

Description

Liquid Crystal Display {LIQUID CRYSTAL DISPLAY}

1 is a perspective view showing a liquid crystal display device according to a first embodiment of the present invention;

2 is a perspective view showing a detailed configuration of the liquid crystal module of FIG.

3 is a cross-sectional view of FIG. 2,

4 is a perspective view illustrating a light guide plate and a heat pipe of FIG. 2;

5 is a perspective view illustrating a light guide plate and a heat pipe in a liquid crystal module of a liquid crystal display according to a second exemplary embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

1: liquid crystal module 10: liquid crystal panel

20: backlight unit 21: light guide plate

21a, 21b: entrance face 22, 23: LED unit

30: bottom chassis 40, 50: heat pipe

60, 61: heat radiation fins 70, 71: blowing fan

The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device capable of efficiently dissipating heat generated from a backlight unit to the outside.

The liquid crystal display has a thin film transistor substrate, a color filter substrate, and a liquid crystal panel made of liquid crystal injected between both substrates. The liquid crystal display further includes a backlight unit for supplying light to the liquid crystal panel because the liquid crystal panel is a non-light emitting device. At this time, the amount of light emitted from the backlight unit is adjusted according to the arrangement of the liquid crystals.

Such a backlight unit is classified into a direct type and an edge type according to the position of the light source.

Here, the edge type backlight unit is mainly used for a relatively small liquid crystal display device such as a monitor of a laptop computer, a monitor of a desktop computer, and a monitor of a portable terminal. The backlight unit includes a light guide plate disposed behind the liquid crystal panel, a lamp unit disposed along at least one side of the light guide plate to supply light to the liquid crystal panel, and light disposed on the light guide plate and guided by the light guide plate to the liquid crystal panel. And optical sheets for diffusing or condensing. Here, the lamp unit may be an EL (Electro Luminescence), CCFL (Cold Cathode Fluorescent Lamp), HCFL (Hot Cathode Fluorescent Lamp), EEFL (External Electrode Fluorescent Lamp), LED (Light Emitting Diode). With this configuration, the light emitted from the lamp unit can be incident on the liquid crystal panel by changing the path of the light by the light guide plate and the optical sheets.

By the way, in the conventional liquid crystal display device, a light phenomenon occurs in the light guide plate or the optical sheets due to heat generated from the lamp unit, thereby lowering luminance and causing color shift.

Accordingly, an object of the present invention is to provide a liquid crystal display device capable of efficiently dissipating heat generated in a backlight unit to the outside.

The object is, according to the present invention, a liquid crystal panel in which an image is formed; A backlight unit disposed behind the liquid crystal panel to supply light to the liquid crystal panel; A bottom chassis accommodating the backlight; It is achieved by a heat pipe that discharges heat from the backlight unit to the outside of the bottom chassis.

The backlight unit may include a light guide plate having at least one incident surface; It is preferable to include an LED unit provided along the incident surface of the light guide plate to supply light to the liquid crystal panel.

At least one region of the heat pipe may contact the front surface of the LED unit, and at least one end thereof may be exposed to the outside of the bottom chassis.

Preferably, the incident surfaces of the light guide plate are provided in pairs, and each of the incident surfaces is disposed to face each other, and the heat pipes are provided in pairs corresponding to the respective incident surfaces.

The incidence surface of the light guide plate may include an upper incidence surface and a lower incidence surface disposed in an up and down direction, and the heat pipe provided on the upper incidence surface side may be coupled to the LED unit almost in parallel.

The heat pipe provided on the lower incidence surface side is provided with a first conducting portion in contact with the front surface of the LED unit, and conducts heat generated from the LED unit, and extends upwardly from the first conducting portion and is adjacent to each incidence surface of the light guide plate. And a second conductive portion contacting the surface and a third conductive portion extending from the second conductive portion and exposed to the outside of the bottom chassis.

The light guide plate may have a quadrangular shape, and the second conductive parts may be provided in a pair to be in contact with both side surfaces adjacent to each of the incident surfaces, and the third conductive parts may be provided in pairs corresponding to each of the second conductive parts. Do.

It is preferable that a plurality of heat dissipation fins are coupled to both ends of each heat pipe.

It is preferable to further include a blowing fan installed adjacent to the heat dissipation fins.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 to 4, the liquid crystal display according to the first exemplary embodiment of the present invention includes a liquid crystal panel 10 in which an image is formed and a liquid crystal panel 10 disposed behind the liquid crystal panel 10. A backlight unit 20 for supplying light to the backlight unit, a bottom chassis 30 disposed under the backlight unit 20 to accommodate the backlight unit 20, and a bottom chassis 30 disposed above the liquid crystal panel 10. A liquid crystal module 1 having a top chassis 37 coupled to the 30 and heat pipes 40 and 50 for dissipating heat from the backlight unit 20 to the outside of the bottom chassis 30; A main substrate (2) for applying a signal to the liquid crystal module (1) between the liquid crystal module (1); The front cover 80 and the rear cover 90 disposed on the front and rear of the liquid crystal module 1 and the main board 2 to cover the liquid crystal module 1 and the main board 2 are included.

The liquid crystal panel 10 includes a thin film transistor substrate 11, a color filter substrate 12, and a liquid crystal layer (not shown) injected between both substrates 11 and 12. In the liquid crystal panel 10, an image is formed according to the arrangement of liquid crystals, and since the liquid crystal panel 10 is a non-light emitting device, the backlight unit 20 is required. Here, the liquid crystal panel 10 is equipped with a source printed circuit board 13 and a gate printed circuit board 14 for driving the liquid crystal panel 10.

The driving signals provided from the source printed circuit board 13 and the gate printed circuit board 14 are respectively applied to the data flexible circuit film 15 and the gate flexible circuit film 16 and applied to the liquid crystal panel 10. In this case, the data flexible circuit film 15 and the gate flexible circuit film 16 may drive data for applying driving signals provided from the source printed circuit board 13 and the gate printed circuit board 14 to the liquid crystal panel 10. The chip 15a and the gate driving chip 16a are mounted, respectively.

 The backlight unit 20 is disposed behind the liquid crystal panel 10 and is provided along the light guide plate 21 having at least one entrance surface 21a and 21b and along the entrance surfaces 21a and 21b of the light guide plate 21. LED units 22 and 23 for supplying light to the panel 10 and an optical sheet disposed on the light guide plate 21 to diffuse or focus light guided from the LED units 22 and 23 to the light guide plate 21. Class 25. The backlight unit 20 is accommodated in the bottom chassis 30 disposed below. Here, the bottom surface of the bottom chassis 30 is accommodated by the reflective sheet 35 for reflecting the light leaking in the opposite direction of the liquid crystal panel 10 among the light emitted from the LED units 22 and 23 back to the light guide plate 21. It is.

The light guide plate 21 is formed in a substantially rectangular plate shape, and faces the LED units 22 and 23 so as to face a pair of incident surfaces 21a and 21b through which light is incident, and the incident surfaces 21a and 21b and a predetermined angle. The light is emitted to the liquid crystal panel 10 while facing the reflective sheet 35 and facing the back surface of the liquid crystal panel 10 and the reflective surface 21d on which the light incident from the incident surfaces 21a and 21b is reflected. And an exit surface 21e.

The incident surface of the light guide plate 21 includes an upper incident surface 21a and a lower incident surface 21b disposed in the vertical direction. The upper LED unit 22, which will be described later, is disposed to face the upper incident surface 21a, and the lower LED unit 23, which will be described later, is disposed to face the lower incident surface 21b.

The LED units 22 and 23 are provided in pairs, the upper LED unit 22 for irradiating light to the upper incident surface 21a, and the lower LED unit 23 for irradiating light to the lower incident surface 21b. It includes. Here, the LED units 22 and 23 are arranged in a line along each of the incident surfaces 21a and 21b in which the LED units for which red (R), green (G), and blue (B) are mixed to emit white light are arranged.

The heat pipes are provided in pairs corresponding to each of the LED units 22 and 23, and the upper heat pipe 40 in contact with the upper LED unit 22 and the lower heat pipe in contact with the lower LED unit 23 ( 50).

The upper heat pipe 40 extends from both ends of the upper LED contact portion 41 contacting the front surface of the upper LED unit 22 and the upper LED contact portion 41 and is exposed to the outside of the bottom chassis 30. (42, 43). At this time, the upper heat pipe 40 is preferably coupled in parallel with the upper LED unit 22. Accordingly, the heat generated in the upper LED unit 22 may move along the upper LED contact portion 41 to be conducted to the upper exposure portions 42 and 43 and be discharged to the outside of the bottom chassis 30.

Here, it is preferable that a plurality of heat dissipation fins 60, 61 are coupled to both ends of the upper heat pipe 40, that is, the upper exposed portions 42 and 43, respectively. Thus, the cross-sectional area is wider by the plurality of heat dissipation fins 60 and 61, so that heat dissipation can be more effectively performed.

The lower heat pipe 50 extends upwardly from both ends of the first conductive portion 51 and the first conductive portion 51 in contact with the front surface of the lower LED unit 23 to conduct heat generated from the lower LED unit 23. And a pair of second conductive parts 52 and 53 contacting each of the incidence surfaces 21a and 21b of the light guide plate 21 and the adjacent side surfaces 21c and bottoms extending from the second conductive parts 52 and 53, respectively. And third conductive parts 54 and 55 exposed to the outside of the chassis 30. Accordingly, the heat generated by the lower LED unit 23 is conducted to the third conductive parts 54 and 55 through the first conductive part 51 and the second conductive parts 52 and 53 to be discharged to the outside of the bottom chassis 30. Can be. Here, since the second conductive parts 52 and 53 of the lower heat pipe 50 are bent upwardly vertically from the first conductive part 51, the fluid in the lower heat pipe 50 may be smoothly flown. That is, when the lower heat pipe 50 absorbs heat from the lower LED unit 23, the liquid in the lower heat pipe 50 is phase-changed into a gas, at which time the gas is formed by the second conductive parts 52 and 53. It can be moved up smoothly and the liquid is quickly moved to the first conductive portion 51 side by gravity can improve the thermal conductivity efficiency.

Since the second conductive parts 52 and 53 are in contact with both side surfaces 21c adjacent to each of the entrance surfaces 21a and 21b of the light guide plate 21, heat existing on both side surfaces 21c of the light guide plate 21 can also be efficiently moved to the outside. Can be released.

Here, it is preferable that a plurality of heat dissipation fins 60, 61 are coupled to both ends of the lower heat pipe 50, that is, the third conductive parts 54 and 55. Thus, the cross-sectional area is wider by the plurality of heat dissipation fins 60 and 61, so that heat dissipation can be more effectively performed.

Each of the heat dissipation fins 60 and 61 is provided with an upper through hole (not shown) and a lower through hole (not shown) to allow the upper heat pipe 40 and the lower heat pipe 50 to pass therethrough.

Here, it is preferable that the blowing fans 70 and 71 are installed to be adjacent to the heat dissipation fins 60 and 61. Here, the blower fans 70 and 71 may discharge heat to the outside more efficiently by forcibly blowing heat conducted by the radiating fins 60 and 61. At this time, air may enter and exit the liquid crystal display in the rear cover 90, and vent holes 90a and 90b are formed to correspond to the positions of the blower fans 70 and 71. Here, the blower fan (70, 71) is of course to be installed so that the air can contact between each of the heat radiation fins (60, 61).

The optical sheets 25 are disposed on the light guide plate 21 and have a bead-shaped coating layer formed thereon to diffuse light incident from the light guide plate 21 and the upper part of the diffusion film 26. A prism film 27 for condensing light in the vertical direction of the liquid crystal panel 10 and a protective film 28 provided between the liquid crystal panel 10 and the prism film 27 to protect the liquid crystal panel 10. Include.

The diffusion film 26 may be used by overlapping two or three sheets.

The prism film 27 is normally used as a regular prism film and an inverted prism film, and two microprisms formed on each prism film form a predetermined angle. Thus, the light incident from the diffusion film 26 mostly proceeds perpendicularly to the liquid crystal panel 10, so that the luminance may be uniform.

The bottom chassis 30 has a rectangular shape to accommodate the liquid crystal panel 10 and the backlight unit 20 therein. In addition, the bottom chassis 30 exposes the upper exposed portions 42 and 43 of the upper heat pipe 40 and the third conductive portions 54 and 55 of the lower heat pipe 50 to be exposed to the outside, respectively. 30b) is formed.

In the above-described embodiment, both ends of the upper heat pipe 40 and the lower heat pipe 50 are exposed to the outside of the bottom chassis 30, but as shown in FIG. 5, the upper heat pipe 240 and the lower heat pipe ( Of course, only one end of the 250 may be exposed to the outside of the bottom chassis 230.

In the above-described embodiment, the LED unit and the heat pit are disposed above and below the light guide plate, but may be disposed on both sides of the light guide plate.

As described above, according to the present invention, a liquid crystal display device capable of efficiently dissipating heat generated in a backlight unit to the outside is provided.

Claims (9)

A liquid crystal panel in which an image is formed; A light guide plate disposed behind the liquid crystal panel and having a first entrance surface and a second entrance surface facing each other; An LED unit including a first LED unit corresponding to the first entrance surface and a second LED unit corresponding to the second entrance surface; A bottom chassis accommodating the light guide plate and the LED unit; And a heat pipe having a first heat pipe corresponding to a first LED unit and a second heat pipe corresponding to the second LED unit to cool the heat of the LED unit. The method of claim 1, And at least a portion of the heat pipe is in contact with the LED unit and at least one end thereof is exposed to the outside of the bottom chassis. The method of claim 1, The first LED unit is extended long, And the first heat pipe extends substantially in parallel with the first LED unit. The method according to any one of claims 1 to 3, The second heat pipe may include a first conductive part contacting the second LED unit, a second conductive part bent from the first conductive part to face a surface adjacent to the second incident surface of the light guide plate, and the second conductive part. And a third conductive portion bent from the lower portion and exposed to the outside of the bottom chassis. The method of claim 4, wherein And the second conductive parts are provided in pairs so as to face both side surfaces adjacent to each of the second incident surfaces, and the third conductive parts are provided in pairs corresponding to the second conductive parts. The method of claim 5, And a heat dissipation fin coupled to the first heat pipe and the third conductive portion. The method of claim 1, And a heat dissipation fin coupled to an end of the first heat pit. The method of claim 7, wherein An end portion of the second heat pit is coupled to the heat dissipation fin. The method of claim 7, wherein And a blower fan installed adjacent to the heat dissipation fins.

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