JP2002091327A - Flat display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the improvement of fixing strength, the improvement of accuracy of a mounting position, and the reduction of electromagnetic wave radiation from a display surface in a flat display device such as a liquid crystal display. SOLUTION: The size of a polarizing plate 112 stuck to the liquid crystal display device 11 is made larger than the size of a glass substrate 111 composing a display surface. In a position determined on the basis of an image pattern displayed on the display surface, both ends of the large-sized polarizer 112 are screwed and fixed to a backlight unit 12. A transparent electrode 117 is formed all over the polarizer 112 of the display surface side of the liquid crystal display device 11, and electromagnetic radiation from the display surface is shielded by grounding the transparent electrode 117.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel display such as a liquid crystal display, and more particularly to an assembling technique for accommodating a flat panel display device in a bezel and a backlight unit and an electromagnetic shielding technique for the flat panel display device.

[0002]

2. Description of the Related Art Conventionally, various flat display devices have been developed. Among them, a liquid crystal display device using a liquid crystal layer as a light modulation layer has been developed in various fields by utilizing the characteristics of light weight, thin shape, and low power consumption. Used in

Here, a structure of a general transmission type liquid crystal display device will be briefly described with reference to FIG. The liquid crystal display device 31 is composed of two transparent glass substrates (or plastic substrates) sandwiching a liquid crystal layer, and a polarizing plate attached to each plate surface (both are omitted from the reference numerals). The flat display device 31 has a backlight unit 32 with glass (or plastic portion) other than the display surface, that is, the peripheral portion stopped with double-sided tape.
And bezel 33 to fix it. Alternatively, the flat display device 31 is simply fixed by being sandwiched between the backlight unit 32 and the bezel 33.

The above-mentioned polarizing plate functions as a filter for light incident from a light source (not shown) arranged on the back of the device, and displays light controlled by the polarization action of the liquid crystal layer in gradation. Has become. As described above, since the polarizing plate is a component that exclusively acts on the display function, a polarizing plate larger than the display area on the glass substrate surface sandwiching the liquid crystal layer is not attached.

[0005]

In the conventional general liquid crystal display device as described above, if the size is the same, a portion other than the effective display area, that is, a peripheral portion for fixing the flat display device 31 is used. Preferably, it is smaller. However, since the liquid crystal display device 31 is fixed by using a double-sided tape as described above, or simply by sandwiching the backlight unit 32 and the bezel 33,
The fixing strength of the relatively heavy flat display device 31 may be insufficient.

[0006] In addition, it is difficult to obtain mounting accuracy higher than the assembly tolerance accuracy without special measures or equipment in mounting. Therefore, the positional accuracy of the liquid crystal display device 31 with respect to the decorative plate mounted by the set maker is not necessarily sufficient. There was a problem that it did not become something.

[0007] Further, from the viewpoint of electromagnetic wave interference, there is no shield against electromagnetic wave radiation from the display surface of the liquid crystal display device 31, so that at present, the radiation level of electromagnetic waves cannot be reduced. .

It is an object of the present invention to provide a flat display device capable of improving the fixing strength and mounting position accuracy of a device and reducing electromagnetic radiation from a display surface.

[0009]

Means for Solving the Problems To achieve the above object, the invention of claim 1 provides a flat display device in which polarizing plates are attached to both surfaces of two transparent substrates sandwiching a light modulation layer.
In the flat display device formed by being sandwiched between the housing frame and the housing member, at least one of the polarizing plates attached to both surfaces of the flat display device is larger than the transparent substrate, and has a size larger than the transparent substrate. It is characterized in that both ends of the polarizing plate are fixed to the housing member.

According to a second aspect of the present invention, in the first aspect, a position of a fixing member for fixing both ends of the polarizing plate to the housing member is displayed on a display surface of the flat display device. It is characterized in that it is determined based on an image pattern.

Further, the invention of claim 3 is the invention of claim 1 or 2
Wherein a transparent electrode is formed on the entire surface of the polarizing plate attached to the display surface of the flat display device, and the transparent electrode is connected to a ground potential.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which a flat display device according to the present invention is applied to a transmission type liquid crystal display device will be described below with reference to the drawings.

FIG. 1 is a schematic perspective view showing the structure of the liquid crystal display device according to the present embodiment. The liquid crystal display device 10
It can be roughly classified into a liquid crystal display device 11, a backlight unit 12 as a housing member, and a bezel 1 as a housing frame.
3 and has a structure in which the liquid crystal display device 11 is sandwiched and fixed between the backlight unit 12 and the bezel 13.

The liquid crystal display device 11 is composed of two glass substrates 111 and 113 filled with a liquid crystal layer (not shown), and has an image display surface formed on one surface. A polarizing plate 112 is attached to the surface of a glass substrate 111 that forms this display surface.
13, a polarizing plate (not shown) is also attached. The polarizing plate 112 has a size larger in the horizontal direction than the glass substrates 111 and 113. A printed circuit board (PCB) 116 is connected to the glass substrate 113 via FPCs 114 and 115.

Mounting holes are formed at both ends of the polarizing plate 112, and fixing screws 141 to 146 as fixing members are attached to the backlight unit 12 through these mounting holes.
Fixed at. The entire surface of the glass substrate 111 is the polarizing plate 1.
Since the liquid crystal display device 11 is firmly fixed to the backlight unit 12 with the fixing screws 141 to 146 via the polarizing plate 112, the liquid crystal display device 11 is further sandwiched by the bezel 13. It is.

Next, a method of positioning the liquid crystal display device 11 to which the polarizing plate 112 has been attached to the backlight unit 12 will be described.

First, the polarizing plate 112 is attached to the glass substrate 111. At this point, no screw holes are provided in the polarizing plate 112 for mounting. Next, FP is applied to the glass substrate 113.
The PCB 116 is connected via C114 and C115. Thereafter, a signal of an image pattern for positioning is input to the PCB 116 from the outside, and the pattern for positioning is displayed on the display surface. Then, holes are made at both ends of the polarizing plate 112 with reference to the positioning pattern displayed on the display surface. As a result, the mounting hole is always formed at an accurate position with respect to the positioning pattern displayed on the display surface. Thereafter, the polarizing plate 112 is fixed to the backlight unit 12 with fixing screws 141 to 146, and the bezel 13 is further attached.

Next, shielding of electromagnetic wave radiation from the display surface will be described with reference to FIG. FIG. 2 is a schematic perspective view showing the structure of the liquid crystal display device according to the embodiment similarly to FIG. 1, and particularly shows the structure of a portion for shielding electromagnetic waves. In FIG. 2, the same parts as those in FIG. 1 are denoted by the same reference numerals.

A transparent electrode 117 is formed on the entire surface of the polarizing plate 112 attached to the glass substrate 111. The transparent electrode 117 has a polarizing plate 112 and mounting screws 14.
An earth tag 25, which is fastened together at 3, is connected. Further, the other end of the ground tag 25 is connected to the printed circuit board 116.
By connecting the ground (ground potential) of the transparent electrode 1
17 is grounded. Since the transparent electrode 117 is formed over the entire surface of the polarizing plate 112, the entire display surface of the liquid crystal display device 11 is electromagnetically shielded by the transparent electrode 117.

According to the above embodiment, the polarizing plate 11 larger than the display surface is provided on the glass substrate 111 of the liquid crystal display device 11.
By attaching 2, portions to be fixed to the backlight unit 12 with fixing screws 141 to 146 can be secured at both ends of the polarizing plate 112. Therefore, the liquid crystal display device 11 is
The fixing strength of the liquid crystal display device 10 is increased as compared with a conventional structure in which a double-sided tape is used or a structure in which the liquid crystal display device 10 is simply sandwiched between a housing frame and a housing member. Can do things.

The hole in the polarizing plate 112 is formed on the basis of an image pattern for positioning displayed on the display surface, so that the distance between the inner peripheral portion of the opening of the bezel 13 and the outer peripheral portion of the display surface is determined by assembling tolerance. Higher dimensional accuracy can be obtained. For this reason, for example, the positional accuracy of the liquid crystal display device 11 with respect to the decorative plate attached by the set maker can be made sufficiently high, and defects such as the decorative plate covering the display area or the bezel 13 being visible can be completely eliminated. And it can prevent stably.

Further, by making the color of the polarizing plate 112 and that of the glass substrate 111 the same, even when the edge of the glass substrate 111 is slightly hidden outside the edge of the glass substrate when the edge of the glass substrate 111 is hidden by the bezel 13 or the like. Since the taste is covered with the same polarizing plate 112, it is difficult to distinguish the appearance from the glass substrate 111, and the dimensional accuracy can be given a margin.

Further, by shielding the transparent electrode 117 formed on the polarizing plate 112 from the display surface of the liquid crystal display device 11 with the earth tag 25, the polarizing plate 112 can have an electromagnetic wave shielding effect. Thus, the radiation level of electromagnetic waves generated from the display surface can be reduced.

In the above embodiment, the glass substrate 111
The size of the polarizing plate 112 on the side
However, the size of the polarizing plate to be attached to the glass substrate 113 side is changed to the size of the glass substrate 11.
1, 113 or glass substrate 1
The size of both polarizing plates 11 and 113 is changed to the glass substrate 11
Even if it is larger than 1, 113, with the same configuration,
Similar effects can be obtained.

[0025]

As described above in detail, according to the flat panel display according to the present invention, a polarizing plate having a size larger than the transparent substrate forming the display surface of the flat panel display is attached to the flat panel display. Since the flat panel display device and the housing member are fixed at both ends of the polarizing plate, the flat panel display device is compared with a conventional structure using double-sided tape or simply sandwiching between the housing frame and the housing member. The fixing strength can be improved.

Further, the positions of the fixing members formed at both ends of the polarizing plate are determined on the basis of the positioning image pattern displayed on the display surface, so that no special device or equipment is required. In addition, it is possible to obtain a mounting accuracy higher than the assembly tolerance accuracy.

Further, since the transparent electrode is formed on the entire surface of the polarizing plate and is grounded, the polarizing plate can be provided with an electromagnetic wave shielding effect, and the radiation level of the electromagnetic wave generated from the display surface can be reduced. can do.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing the structure of a liquid crystal display device according to an embodiment.

FIG. 2 is a schematic perspective view showing the structure of the liquid crystal display device according to the embodiment.

FIG. 3 is a schematic perspective view showing a structure of a general transmission type liquid crystal display device.

[Explanation of symbols]

10: Liquid crystal display device, 11: Liquid crystal display device, 12:
Backlight unit, 13: bezel, 25: ground tag, 111, 113: glass substrate, 112: polarizing plate, 1
14, 115: FPC, 116: Printed circuit board (PC
B) 117: transparent electrode; 141 to 146: fixing screw

Continued on front page F term (reference) 2H089 HA40 QA02 QA10 TA02 TA15 TA18 2H091 FA08X FA08Z FD03 FD11 FD15 GA03 LA08 2H092 GA64 JB79 NA14 NA25 NA30 PA11 PA13 5G435 AA16 BB12 FF05 GG33 KK05

Claims (3)

[Claims] 1. A flat display device formed by sandwiching a flat display device in which polarizing plates are attached to both surfaces of two transparent substrates sandwiching a light modulation layer between a housing frame and a housing member, The size of at least one of the polarizing plates attached to both sides of the device is larger than the transparent substrate,
A flat display device, wherein both ends of a polarizing plate having a size larger than the transparent substrate are fixed to the housing member. 2. The method according to claim 1, wherein a position of a fixing member for fixing both ends of the polarizing plate to the housing member is determined based on a positioning image pattern displayed on a display surface of the flat display device. The flat display device according to claim 1. 3. The flat panel display device according to claim 1, wherein a transparent electrode is formed on the entire surface of the polarizing plate attached to the display surface of the flat display device, and the transparent electrode is connected to a ground potential. Flat panel display.