JP3222519B2 - Liquid crystal display - Google Patents

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 used for displaying images on a personal computer, a word processor, a TV, a viewfinder of a video camera, and the like. More specifically, the present invention relates to an exterior structure of a liquid crystal panel.

[0002]

2. Description of the Related Art In order to facilitate understanding of the present invention, a general structure of a liquid crystal panel will be briefly described with reference to FIG. As shown in the figure, the liquid crystal panel 1 is composed of a pair of glass substrates 2 and 3 opposed to each other with a predetermined gap therebetween, and a liquid crystal layer 4 filled and filled in the gap. The pair of glass substrates 2 and 3 are bonded to each other through the seal 5. A transparent electrode 6 made of ITO or the like is patterned on the inner surface of each substrate. When a driving voltage is applied between the transparent electrodes facing each other, the transmittance of the liquid crystal layer 4 is selectively changed, and an image is displayed. Since the substrates 2 and 3 are generally made of a glass material, chipping or the like may occur if an excessive external force is applied, and there is a fear that the panel end faces may be damaged. Even if the liquid crystal layer 4 is not damaged, if the thickness of the liquid crystal layer 4 partially changes due to stress strain, display unevenness appears and the image quality deteriorates. Therefore, the liquid crystal panel 1 is generally housed in an outer case to constitute a liquid crystal display device.

FIG. 4 shows an example of an exterior structure of a conventional liquid crystal display device. The liquid crystal panel 1 is housed in a recess 8 provided in an outer case 7. The bottom 9 of the outer case 7 supports the lower surface of the liquid crystal panel 1 by surface contact. On the other hand, the opening of the concave portion 8 in which the panel 1 is stored is covered by the lid member 12. The liquid crystal panel 1 is sandwiched from above and below by pressing the outer case 7 and the flange portion of the lid member 12 with each other by screws, so that the liquid crystal panel 1 is sandwiched.

[0004]

Problems to be solved by the invention will be described with reference to FIG. The outer case 7 is generally manufactured by injection molding a resin. Because of this,
The dimensional accuracy is not always high. In particular, there is a limit in increasing the surface accuracy or flatness of the bottom 9. Therefore, the lower surface of the panel 1 and the bottom 9 are not always in close contact with each other, and there may be a gap as shown in the figure. In such a state, the pressing force applied to the panel 1 becomes non-uniform, so that there is a problem that display unevenness occurs and adversely affects image quality. or,
Not only the surface accuracy of the bottom portion 9 but also the depth dimension of the concave portion 8 varied, so that the liquid crystal panel 1 could not always be sandwiched in a state of being in close contact. For this reason, an excessive stress may be applied in the thickness direction of the liquid crystal panel 1, which may cause breakage of the glass substrate.

In order to improve the reliability of the liquid crystal panel 1, a molding material 1 is provided between the outer peripheral surface of the panel and the inner wall surface of the outer case 7.
5 may be filled. However, the outer case 7
In the case where there is a gap between the liquid crystal panel 1 and the bottom 9 due to poor dimensional accuracy of the liquid crystal panel 1, the molding material 15 flows out,
There is a problem that the display screen is stained. In other words, since the surface accuracy of the bottom portion 9 is poor, it is impossible to completely seal the mold material 15 having fluidity, and the mold seeps out.

In the case of a large-sized liquid crystal display device having a large screen, the dimensional accuracy error of the outer case, the amount of flow of the mold, and the like are generally small compared to the size of the large-sized liquid crystal display device, so that there is not much problem. However, like an active matrix type liquid crystal display device using a TFT,
As the panel becomes thinner, smaller, or more precise,
The above-mentioned problems in the exterior structure become significant. Therefore, the present invention is applicable to a case where the liquid crystal panel is downsized.
An object of the present invention is to provide an exterior structure having excellent outer shape accuracy, appearance quality, and impact resistance.

[0007]

Means taken to solve the above-mentioned problems or problems of the prior art and to achieve the object of the present invention are as follows. That is, the liquid crystal display device according to the present invention has, as its basic components, a liquid crystal panel having a pair of glass substrates having a transparent electrode on the inner surface and a liquid crystal layer sandwiched between the substrates, and holds the liquid crystal panel. It has an integral structure consisting of an outer case. As a characteristic matter, the outer case has a protrusion such that a contact surface with one flat surface of the liquid crystal panel has a continuous loop shape, and a molding material or a filler is filled in a gap between the liquid crystal panel and the outer case. I have arranged. Further, a cover member is arranged so as to cover the opening surface of the outer case holding the liquid crystal panel. The lid member is in close contact with the flat surface on the other side of the liquid crystal panel, and is joined to the peripheral portion of the outer case to press the liquid crystal panel from above and below.
In addition, the protrusions can be deformed according to the pressing force,
The dimensional error of the mounting case can be absorbed.

[0008]

In the mounting structure of the present invention, even if the outer case has some dimensional error, deformation or distortion, it is possible to obtain almost perfect surface contact by pressing the lower surface of the liquid crystal panel against the projection. It is possible. The projection can absorb some surface accuracy error or dimensional error, so that the thickness accuracy of the entire liquid crystal display device can be maintained at a practical level. Further, since non-uniform stress and excessive external force are not applied to the end face of the liquid crystal panel, panel damage such as glass chipping can be prevented, and display unevenness can be suppressed. Furthermore, since the contact area with the glass substrate can be reduced by reducing the size of the projection, when a pressing force is applied to the panel from above and below, the pressure per unit area at the contact section increases, and the A stable sealing effect can be obtained, and it is possible to prevent runoff and seepage.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic sectional view showing a mounting structure of a liquid crystal display device according to the present invention. This device has an integral structure of the liquid crystal panel 1 and the outer case 7. The liquid crystal panel 1 has a general configuration as shown in FIG.
It has a pair of glass substrates 2 and 3 bonded to each other.

On the other hand, the outer case 7 is provided with a concave portion 8 having a predetermined depth, and accommodates the liquid crystal panel 1. An opening 10 is provided in the bottom 9 of the outer case 7 to expose an image surface of the liquid crystal panel 1. A projection 11 is provided along the inner end surface of the bottom 9 so as to surround the opening 10. The protrusion 11 is in contact with the surface of the lower glass substrate 2 of the liquid crystal panel 1.

A cover member 12 is arranged so as to cover the opening of the concave portion 8 in which the liquid crystal panel 1 is stored. The lid member 12 has a flat plate shape, and is joined to the flange portion 13 of the outer case 7 at the periphery. This connection is made, for example, with a screw 14
This is performed using LCD panel 1 when screw is tightened
Pressing force is applied to the glass substrate 3 from above and below.
And the protrusion 11 is in close contact with the lower surface of the glass substrate 2. At this time, since the protrusion 11 is slightly deformed in accordance with the pressing force, the dimensional error of the outer case 7 can be absorbed, and the thickness dimensional accuracy of the liquid crystal display device can be maintained.
In addition, since the protrusions 11 are arranged on the inside away from the end surface of the glass substrate 2, there is no fear of glass chipping or the like.

A filler 15 is injected into a gap between the inner wall of the recess 8 and the outer peripheral surface of the liquid crystal panel 1 to enhance the reliability of the liquid crystal panel 1. As the material of the filler 15, for example, a room temperature curing type silicone rubber can be used. Before joining the lid member 12, fluid silicone rubber is injected using a dispenser or the like. Since it is a room temperature curing type, it cures naturally without requiring heat treatment. For this reason, there is no fear of applying a thermal stress to the liquid crystal panel 1. In addition, since the silicon-based rubber has a predetermined elasticity, it can absorb an impact force or the like applied to the liquid crystal panel 1 to some extent. Further, since the outer peripheral surface of the liquid crystal panel 1 is covered, moisture resistance and the like are improved. The projection 11 has a continuous loop shape in plan view, and seals a gap between the liquid crystal panel 1 and the outer case 7. For this reason, since the filler 15 having fluidity does not flow toward the opening 10, the image surface of the liquid crystal panel 1 is not stained.

FIG. 2 shows a bottom view of the liquid crystal display device shown in FIG. As described above, the bottom 9 of the outer case 7
Is provided with an opening 10, and the image surface of the liquid crystal panel 1 is exposed. In the drawing, the dashed line indicates the liquid crystal panel 1.
Represents the outer peripheral shape of the lower glass substrate 2 constituting the above. Also, as shown by the dotted line, the protrusion 11
Is provided. The projection 11 has a continuous loop shape in plan view, is in close contact with the surface of the glass substrate 2 everywhere, and has a substantially perfect sealing structure.
Therefore, the filler does not flow out to the image surface surrounded by the sealing.

The outer case 7 is generally manufactured by molding a resin using a mold or the like. It is preferable that the width of the protrusion 11 be smaller since the contact pressure per unit area increases and the closeness to the glass substrate is improved. In addition, the thinner, the easier the plastic deformation becomes, so that it becomes easier to conform to the surface of the glass substrate 2. However, there is a limit in the width dimension of the projection 11 due to the design of the mold or the molding process, and a minimum dimension of about 0.3 mm is required for stable molding. In addition, in order to support the liquid crystal panel 1 against the pressing force, a width of about 0.3 mm is also required at a minimum.

[0015]

As described above, according to the present invention, a continuous loop-shaped projection is provided on the bottom of the outer case,
This provides a structure that supports the liquid crystal panel. Therefore, the contact area can be reduced as compared with the conventional case, so that the pressing force per unit area increases, and the liquid crystal panel and the outer case can be integrated with high accuracy. In other words, since the projection has a function of absorbing a dimensional error, there is an effect that an assembling dimensional error between the liquid crystal panel and the outer case can be tolerated. In addition, since the sealing property is also improved, there is no fear that the mold resin leaks toward the image surface, and the appearance quality of the liquid crystal display device can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a mounting structure of a liquid crystal display device according to the present invention.

FIG. 2 is a bottom view of the liquid crystal display device shown in FIG.

FIG. 3 is a cross-sectional view illustrating a general structure of a liquid crystal panel.

FIG. 4 is a cross-sectional view showing a conventional mounting structure of a liquid crystal display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal panel 2 Glass substrate 3 Glass substrate 7 Outer case 8 Concave part 9 Bottom part 10 Opening 11 Projection part 12 Lid member 13 Flange 14 Screw 15 Filler

Claims (1)

(57) [Claims] 1. A liquid crystal panel comprising: a pair of substrates having a transparent electrode on an inner surface; and a liquid crystal layer sandwiched between the substrates.
In a liquid crystal display device including an outer case holding the liquid crystal panel and a lid member covering an opening surface of the outer case holding the liquid crystal panel, the outer case has a continuous contact surface with one flat surface of the liquid crystal panel. A projection having a loop shape is provided, and a filler is provided in a gap between the liquid crystal panel and the outer case.The lid member is in close contact with the other flat surface of the liquid crystal panel and is joined to a peripheral portion of the outer case. The liquid crystal panel is pressed from above and below, and the projection is deformable according to the pressing force.
A liquid crystal display device characterized by being able to absorb a dimensional error of an outer case .