JPH05142559A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To provide a thin type and lightweight liquid crystal display device whose structure is simplified and having a small number of parts. CONSTITUTION:As to the liquid crystal display device provided with a frame 1, a liquid crystal display element 3, a driving circuit substrate 4 electrically connected with the liquid crystal display element 3 through a TAB 5 and a light guide plate 9 whose size is nearly the same as the liquid crystal display element 3 and which is arranged under the liquid crystal element 3 and also having a back light 10, the driving circuit substrate 4 is arranged on the back side of the light guide plate 9 through a bent TAB 5, and projecting parts 13 are installed on both sides of the light guide plate 9, and the frame 1 and the driving circuit substrate 4 are fixed on the projecting parts 13. Since the light guide plate 9 functions as a supporting body for each packaging component without using conventional mold, the thin type and lightweight liquid crystal display device whose structure is simplified and having a small number of parts is provided.

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 particular, the present invention relates to a technique suitable for realizing a thin and lightweight liquid crystal display device.

[0002]

2. Description of the Related Art FIG. 6 is an exploded perspective view showing a conventional liquid crystal display device.

Reference numeral 61 is a frame, 62 is a spacer, 63 is a liquid crystal display element composed of two upper and lower transparent glass substrates and liquid crystal enclosed between them, and 64 is a drive circuit board (PC).
B), 65 is a TAB for electrically connecting the liquid crystal display element 63 and the drive circuit board 64, 66 is a spacer, 67
Is a diffusion plate, 68 is a mold, 69 is a light guide plate, 70 is a backlight such as a cold cathode fluorescent tube (CFL), and 71 is a reflection plate made of a metal plate.

The mold 68 is made of molded synthetic resin and functions as a support for each mounted component.

[0005]

In the above-mentioned conventional technique, the mold 68 is used as a support for each mounting component.
Therefore, there is a problem that the structure is complicated, the number of parts is large, the thickness is thick, and the weight is heavy.

An object of the present invention is to solve the above problems and to provide a thin and lightweight liquid crystal display device having a simple structure, a small number of parts.

[0007]

In order to solve the above problems, according to the present invention, it is possible to discontinue use of a mold as a conventional support member for each mounting component and to support a light guide plate on each mounting component. It has a unique shape and structure.

That is, according to the present invention, the frame, the liquid crystal display element, the drive circuit board electrically connected to the liquid crystal display element through the TAB, and the same size as the liquid crystal display element, In a liquid crystal display device having a light guide plate provided with a backlight, which is arranged below the liquid crystal display element, the drive circuit board is provided on the back side of the light guide plate (the side opposite to the display screen) via the folded TAB. ), The protrusions are provided on both sides of the light guide plate, and the frame and the drive circuit board are directly fixed to the protrusions by screwing or the like.

[0009]

In the present invention, since the light guide plate is provided with the function without using the conventional mold as a support for each mounted component, the structure is simple, the number of components is small, and the liquid crystal display is thin and lightweight. The device can be realized.

[0010]

FIG. 1 is a developed perspective view of a liquid crystal display device according to an embodiment of the present invention.

1 is a frame, 3 is a liquid crystal display element, 4 is a drive circuit board (PCB), 5 is a TAB for electrically connecting the liquid crystal display element 3 and the drive circuit board 4, 6 is a spacer, and 7 is Diffusion sheet, 9 is a light guide plate, 10 is a backlight such as a cold cathode fluorescent tube (CFL), 13 is a protrusion provided on both sides of the light guide plate, 14 and 15 are screw holes provided in the protrusion 13, and 11 is a reflection sheet. , 12 are spacers.

That is, in this embodiment, the drive circuit board 4 is disposed on the back side of the light guide plate 9 (the side opposite to the display screen) via the bent TAB 5. Further, protrusions 13 are provided at four positions on both sides of the light guide plate 9, and the protrusions 1
The frame 1 and the drive circuit board 4 are screwed to the frame 3 via screw holes 14 and 15, respectively. With such a structure, the liquid crystal display element 3, the drive circuit board 4, the frame 1, etc. are supported and fixed by the light guide plate 9, and the light guide plate 9 functions as a support for each mounting component. It is not necessary to use a mold as a support for parts. Therefore, since the mold is not used, the structure can be simplified and the number of parts can be reduced as compared with the related art. As a result, the manufacturing process can be simplified, the manufacturing cost can be reduced, and the thickness and weight can be reduced.
Since the light guide plate has higher strength than the conventional mold and the light guide plate is thicker than the thin portion of the mold, the light guide plate can sufficiently fulfill the function as a support. Further, the drive circuit board 4 is inserted through the bent TAB 5.
Is arranged on the back side of the light guide plate 9, the plane size can be made smaller than that of the conventional device of FIG.

FIG. 2 (a) is a plan view of the assembled device of the embodiment of FIG. 1 seen from the display screen side, FIG. 2 (b).
Similarly, it is a plan view seen from the back side. FIG. 3 shows FIG.
It is an AA sectional view of (a). In these figures, 1
6 is a fixing screw, and 17 is a driving IC. The same parts as those in FIG. 1 are designated by the same reference numerals. As is clear from these figures, the strength of the entire module mainly depends on the light guide plate 9. The apparatus of the present embodiment can be reduced in weight and thickness as compared with the conventional apparatus having the same size because a mold is not used. For example, in the case of 11-inch display, the weight was 540 g in the conventional example, but was 460 g in the present example, which was about 15% lighter. Further, the thickness was about 12 mm in the conventional example, but could be reduced to about 10.5 mm in this example.

FIGS. 4 and 5 are shown in FIGS.
(B) and the embodiment of FIG. 3 are examples when used in a laptop personal computer, FIG. 4 is a block diagram for driving a liquid crystal display device, and FIG. 5 is a laptop type liquid crystal display module. It is an appearance perspective view showing the state where it was built into a personal computer. In FIG. 4, 41 is a microprocessor unit, 42 is a control LSI,
Reference numeral 43 is a liquid crystal display module. The liquid crystal display element 3 is driven by the driving IC 17 through the control LSI 42 by the instruction of the microprocessor unit 41. In FIG. 5, reference numeral 51 is a laptop computer, 52 is a brightness volume, 53 is a contrast volume, and 54 is an inversion switch. According to this embodiment, the weight and thickness of the laptop computer can be reduced.

Although the present invention has been specifically described based on the above embodiment, the present invention is not limited to the above embodiment and can be variously modified without departing from the scope of the invention. is there. For example, in the above embodiment,
Although the frame 1 and the drive circuit board 4 are screwed to the protrusion 13 by using the two screw holes 14 and 15, they may be screwed by using one common screw hole. Further, it is not limited to screwing, and other fixing means may be used.

[0016]

As described above, in the liquid crystal display device of the present invention, the conventional mold is not used, and the light guide plate has a function as a support for each mounted component. It is possible to provide a thin, lightweight liquid crystal display device having a small number.

[Brief description of drawings]

FIG. 1 is a developed perspective view of a liquid crystal display device according to an embodiment of the present invention.

2A is a plan view of the assembled device of the embodiment of FIG. 1 viewed from the display screen side, and FIG. 2B is a plan view similarly viewed from the back side.

FIG. 3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a block diagram for driving a liquid crystal display device.

FIG. 5 is an external perspective view showing a state in which the liquid crystal display module is incorporated in a laptop computer.

FIG. 6 is a developed perspective view showing a conventional liquid crystal display device.

[Explanation of symbols]

1 ... Frame, 3 ... Liquid crystal display element, 4 ... Drive circuit board (PCB), 5 ... TAB, 7 ... Diffusion sheet, 9 ... Light guide plate, 10 ... Backlight (cold cathode fluorescent tube), 11 ... Reflection sheet, 13 … Projections, 14, 15… Screw holes.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hitoshi Suzuki, 3300 Hayano, Mobara-shi, Chiba, Hitachi, Ltd. Mobara factory (72) Inventor Takayuki Iura, 3300, Hayano, Mobara-shi, Chiba, Hitachi Ltd., Mobara, Hitachi, Ltd.

Claims (1)

[Claims] 1. A frame, a liquid crystal display element, a drive circuit board electrically connected to the liquid crystal display element through a TAB, and a liquid crystal display element of substantially the same size as the liquid crystal display element. In a liquid crystal display device having a light guide plate provided with a backlight, which is overlapped below, the drive circuit board is arranged on the back side of the light guide plate via the folded TAB, and on both sides of the light guide plate. A liquid crystal display device, wherein a protrusion is provided, and the frame and the drive circuit board are fixed to the protrusion.