JPH07120751A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To facilitate the exchange of a light source while avoiding thermal influence on electronic parts such as an LSI by separately installing the light source in a liquid crystal display device, and to efficiently guide and radiate light from the light source to the back surface side of a liquid crystal display body by using a light guiding member such as an optical fiber (optical cable). CONSTITUTION:An LCD panel 3 and the electronic parts of an integrated circuit for driving the LCD panel 3, for example, the LSI are housed in a unit case 2. A fluorescent tube 11 is installed separately from the unit case 2, and the light from the fluorescent tube 11 is guide to the inside of the unit case 2 by using the optical fiber 8, and guided to a diffusing plate provided on the back surface side of the LCD panel 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device in which a light source for a backlight is provided separately from a liquid crystal display body.

[0002]

2. Description of the Related Art In recent years, a liquid crystal television using a liquid crystal as a display device has been put into practical use. The liquid crystal is thin, lightweight, and has low power consumption, so it is suitable for portable use. However, since the liquid crystal is a light receiving element, a backlight for illumination is necessary. Although a fluorescent tube is conventionally used as a backlight, since the fluorescent tube has a cylindrical shape, light is emitted only from the fluorescent tube portion, and uniform light cannot be spread over the entire liquid crystal display screen.

Therefore, there is a direct type backlight in which a reflection case and a reflection sheet are provided so that the light is evenly distributed over the entire area of the liquid crystal display screen so that the linear light source emitted from the fluorescent tube is entirely distributed. There is also an edge light type backlight in which a straight tube type fluorescent tube is arranged on the side end surface of the transparent light guide body and one surface side is used as a surface light source by utilizing multiple reflection inside the light guide body.

[0004]

As described above, in the conventional backlight, the LCD (L
Although it is arranged on the back side or near the side of the liquid crystal display (liquid crystal display), the LSI (Large Scale) is arranged near the LCD.
When a heat-generating electronic component such as an integration (large-scale integrated circuit) is mounted, the temperature of the electronic component may further increase due to the heat of the backlight, and the LSI or the like may be damaged. I was invited to.
Also, because of this, high-density mounting, and because the lamp life of the light source is short, it is necessary to replace it frequently.
Replacing the lamp was a hassle.

An object of the present invention is, in such a liquid crystal display device, a light source is separately placed to facilitate the replacement of the light source while avoiding the influence of heat on the electronic parts.
For example, a light guide member such as an optical fiber (optical cable) is used so that the light from the light source can be efficiently guided to the back side of the liquid crystal display for irradiation.

[0006]

In order to solve the above problems, the present invention is a liquid crystal display device comprising a liquid crystal display body and an integrated circuit for driving the liquid crystal display body, for example, an electronic component such as an LSI. Store in a case. Then, a light source is placed separately from this case, and the light of this light source is guided into the case using a light guide member, for example, an optical cable, and is guided to, for example, a diffusion plate provided on the back side of the liquid crystal display. .

[0007]

Since the light source is provided separately from the case for accommodating the liquid crystal display and the electronic parts, the electronic parts such as LSI are protected from the influence of the heat of the light source and the light source can be easily replaced. Then, the light of this separately placed light source is guided into the case using a light guide member such as an optical cable, and further,
For example, the liquid crystal display can be efficiently irradiated by being guided to a diffusion plate provided on the back side of the liquid crystal display.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the liquid crystal display device according to the present invention will be described below with reference to FIGS.

1 and 2 showing the structure of a liquid crystal display device as an example to which the present invention is applied, 1 is an LCD unit which is a liquid crystal display unit, 2 is a unit case,
3 is an LCD panel which is a liquid crystal display, 4 is a diffusion plate, 5 is an LSI which is an electronic component, 6 is a buffer member, 7 is a blind plate,
8 is an optical cable formed by a bundle of optical fibers which is a light guide member, 9 is a signal line, 11 is a straight tube type fluorescent tube which is a light source, 1
2 is a light source case.

The LCD unit 1 is formed by accommodating an LCD panel 3, a diffusion plate 4, an LSI 5 and a cushioning member 6 in a unit case 2 and a frame-shaped blinding plate 7 is attached to the screen side thereof. . A band-shaped optical cable 8 formed by a bundle of optical fibers is connected to the diffusion plate 4, and a signal line 9 connected to a circuit board (not shown) is connected to the LSI 5. The optical cable 8 and the signal line 9 are connected to the unit case 2 from the unit case 2. Outsourced.

Further, a light source case 12 accommodating the fluorescent tube 11 is installed at a position apart from the LCD unit 1. The light source case 12 connects the internal fluorescent tube 11 and the optical cable 8 with the optical cable 8 led out from the unit case 2 interposed therebetween.

Specifically, the unit case 2 is composed of a lower case 2a and an upper case 2b, and a unit formed by stacking the LCD panel 3, the diffusion plate 4 and the LSI 5 in order from the top is a buffer such as a mat material. Lower case 2a to which the member 6 is attached
It is placed inside. The diffusing plate 4 diffuses the light introduced into the interior from one end surface almost uniformly and transmits the light upward, and the LSI 5 controls the driving of the LCD panel 3.

Then, a hook 2d protruding from the inner surface of one side of the upper case 2b is locked in a locking groove 2c formed on the inner surface of one side of the lower case 2a, and the other side of the opposite side is locked. Fix the lower case 2a and the upper case 2b at the side with fixing screws 2
e and 2e are combined and fixed to each other. In addition, the fixing screws 2e, 2e have holes 2f formed in the upper case 2b,
It is designed so that it can be tightened inside through 2f.

Further, the holes 2f, 2f are provided in the upper case 2
A frame-shaped blinding plate 7 attached around the display screen 2g of FIG.
Is blocked by. Thus, the LCD unit 1 is hermetically sealed by the unit case 2, which prevents the device 5 from being modified by replacing the LSI 5 integrated with the LCD panel 3, for example.

Further, the strip-shaped optical cable 8 formed by a bundle of optical fibers connected to the diffusion plate 4 and the signal line 9 connected to the LSI 5 are provided from the side portion having the engaging groove 2c and the hook 2d of the lower case 2a and the upper case 2b. It is led out to the outside and is arranged in a notch not shown in the lower case 2a and a notch not shown in the upper case 2b.

The strip-shaped optical cable 8 is sandwiched by the fixing screws 12a and 12a in the light source case 12 while being connected to the fluorescent tube 11 in the light source case 12. As shown in FIG. 1, a part of the light source case 12 is provided with a window 12b for taking out a part of the light of the fluorescent tube 11 as another light source to the outside.

According to the liquid crystal display device having the above configuration, the light emitted from the fluorescent tube 11 in the light source case 12 is emitted from the optical cable 8.
It is guided through the inside into the unit case 2, that is, introduced from one end face of the diffuser plate 4 through the optical cable 8 and diffused almost uniformly in the diffuser plate 4 and transmitted upward, The back surface of the panel 3 is efficiently illuminated. Therefore, a good liquid crystal screen can be obtained.

Since the optical cable 8 has flexibility, the LCD unit 1 and the light source case 12 are excellent in the degree of freedom in disposing each other. Moreover, the fluorescent tube 11 that generates heat is LC
Since it is installed away from D unit 1, LCD
A cooling measure for the panel 3 and the LSI 5 is unnecessary, and the device can be downsized accordingly. Further, since the light source case 12 is provided separately from the LCD unit 1, the fluorescent tube 11 having a short life can be easily replaced.

In the above embodiments, the light guide member is a bundle of optical cables. However, the present invention is not limited to this, and prisms or mirrors may be used instead of optical cables to guide light. May be. Further, it is needless to say that the type of equipment to which the liquid crystal display device according to the present invention is applied is arbitrary, and in addition, specific detailed structures and the like can be appropriately changed.

[0020]

As described above, according to the liquid crystal display device of the present invention, since the light source is provided separately, the electronic components such as the LSI housed in the case together with the liquid crystal display body are protected from the influence of the heat of the light source. In addition, it is possible to easily replace a light source having a short life, and moreover, the light of a separately placed light source is guided by a light guide member such as an optical cable to efficiently illuminate the liquid crystal display in the case. be able to.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing a configuration of a liquid crystal display device as an example to which the present invention is applied.

FIG. 2 is a vertical sectional side view showing the internal structure of the liquid crystal display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal display unit 2 Unit case 3 Liquid crystal display body 4 Diffusion plate 5 Electronic component 6 Buffer member 7 Blind plate 8 Light guide member 9 Signal line 11 Light source 12 Light source case

Claims (1)

[Claims] 1. A liquid crystal display, an electronic component such as an integrated circuit for driving the liquid crystal display, a case accommodating the liquid crystal display and the electronic component, a light source separate from the case, and the light source. And a light guide member for guiding the light of (1) to the liquid crystal display body in the case.