JPH05165014A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To enhance the sealing performance against a mold member and enable the absorption of dimensional errors of an exterior case by improving a mounting structure of a liquid crystal display device. CONSTITUTION:A pair of glass substrates 2 and 3 containing transparent electrodes on their inner surfaces, a liquid crystal panel 1 containing a liquid crystal layer pinched between the substrates, and an exterior case 7 holding the liquid crystal panel are integrated so as to constitute a liquid crystal display device. The exterior case 7 has a protruded part 11 such that the contact surface with the liquid crystal panel surface forms a continuous loop shape, and a mold material or a filler 15 is provided in a gap between the liquid crystal panel 1 and the exterior case 7. A lid member 12 is provided in such a manner that it covers the opening surface of the exterior case holding the liquid crystal panel 1. The liquid crystal panel 1 is pressed downward and upward by using the lid member 12 and the exterior case 7 so that the protruded part 11 intimately contacts with the surface of the liquid crystal panel 1 thereby absorbing the dimensional errors as well as providing a substantially perfect sealing structure.

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 image display in personal computers, word processors, TVs, viewfinders of video cameras and the like. More specifically, it 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 which are arranged to face each other with a predetermined gap, and a liquid crystal layer 4 which is sealed and filled in the gap. The pair of glass substrates 2 and 3 are attached to each other via a sealer 5. A transparent electrode 6 made of ITO or the like is patterned on the inner surface of each substrate. When a drive voltage is applied between the transparent electrodes facing each other, the transmittance of the liquid crystal layer 4 is selectively changed to display an image. Since the substrates 2 and 3 are generally made of a glass material, if an excessive external force is applied, chipping or the like may occur and the panel end surface 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 form a liquid crystal display device.

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

[0004]

The problem 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. Therefore,
The dimensional accuracy is not always high. In particular, there is a limit in increasing the surface accuracy or flatness of the bottom portion 9. Therefore, the lower surface of the panel 1 and the bottom portion 9 are not necessarily in close contact with each other, and a gap may occur as shown in the drawing. In such a state, since the pressing force applied to the panel 1 becomes non-uniform, display unevenness occurs and the image quality is adversely affected. or,
Not only the surface accuracy of the bottom portion 9 but also the depth dimension of the recessed portion 8 varied, and it was not always possible to sandwich the liquid crystal panel 1 from above and below in a tightly contacted state. For this reason, excessive stress may be applied in the thickness direction of the liquid crystal panel 1, causing damage to the glass substrate.

In order to enhance the reliability of the liquid crystal panel 1, the 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
Since the dimensional accuracy is poor, the mold material 15 flows out when a gap is formed between the liquid crystal panel 1 and the bottom portion 9,
There is a problem that the display screen becomes dirty. In other words, the surface accuracy of the bottom portion 9 is poor, so that the mold material 15 having fluidity cannot be completely sealed, and the mold oozes 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 flow-out amount of the mold, etc. are generally smaller than the size of the large-sized liquid crystal display device, so that they do not pose a problem. However, like active matrix liquid crystal display devices using TFTs,
If the panel is made thinner, smaller, or has higher definition,
The above-mentioned problems in the exterior structure become remarkable. Therefore, even when the present invention reduces the size of the liquid crystal panel,
The objective is to provide an exterior structure with excellent external shape accuracy, external appearance quality, and impact resistance.

[0007]

Means for solving the problems or problems of the above-mentioned conventional techniques and achieving the objects of the present invention are as follows. That is, the liquid crystal display device according to the present invention has, as its basic constituent elements, a liquid crystal panel having a pair of glass substrates having transparent electrodes on the inner surface thereof and a liquid crystal layer sandwiched between the substrates, and a liquid crystal panel holding the liquid crystal panel. It has an integral structure consisting of an outer case. Characteristically, the outer case has a protrusion so that the contact surface with the flat surface of the liquid crystal panel becomes a continuous loop shape, and a molding material or a filler is placed in the gap between the liquid crystal panel and the outer case. There is. Further, a lid member is arranged so as to cover the opening surface of the outer case that holds the liquid crystal panel.

[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 substantially perfect surface contact by pressing the lower surface of the liquid crystal panel against the protrusion. It is possible. Since the protrusion can absorb some surface accuracy error or dimensional error, the thickness accuracy of the entire liquid crystal display device can be maintained at a practical level. In addition, since uneven stress or excessive external force is not applied to the end face portion of the liquid crystal panel, it is possible to prevent panel damage such as glass chipping and suppress display unevenness. Furthermore, since the contact area with the glass substrate can be reduced by reducing the dimensions of the protrusions, when pressure is applied to the panel from above and below, the pressure per unit area at the contact area increases, and 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 in detail below 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 integrated structure of a liquid crystal panel 1 and an outer case 7. The liquid crystal panel 1 has a general structure 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 recess 8 having a predetermined depth dimension, and accommodates the liquid crystal panel 1. An opening 10 is provided in the bottom portion 9 of the outer case 7 to expose the image surface of the liquid crystal panel 1. A projecting portion 11 is provided along the inner end surface of the bottom portion 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 lid member 12 is arranged so as to cover the opening of the recess 8 accommodating the liquid crystal panel 1. The lid member 12 has a flat plate shape and is joined to the flange portion 13 of the outer case 7 at the peripheral portion thereof. This connection is made by screws 14
Is performed using. When the screws are tightened, the liquid crystal panel 1
The pressing force is applied from above and below to the protrusion 11
Close to the underside of. At this time, since the protrusion 11 is deformed to some extent according to the pressing force, it is possible to absorb the dimensional error of the outer case 7 and maintain the thickness dimensional accuracy of the liquid crystal display device.
Further, since the protruding portion 11 is arranged on the inner side apart from the end surface portion of the glass substrate 2, there is no fear of glass chipping or the like.

A filling material 15 is injected into the 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, room temperature curable silicone rubber can be used. Before joining the lid member 12, a fluid silicone rubber is injected using a dispenser or the like. Since it is a room temperature curable type, it does not require heat treatment and can be left to stand. Therefore, there is no fear of applying thermal stress to the liquid crystal panel 1. In addition, since the silicone rubber has a predetermined elasticity, it is possible to absorb the impact force applied to the liquid crystal panel 1 to some extent. Moreover, since the outer peripheral surface of the liquid crystal panel 1 is covered, the moisture resistance and the like are improved. The protrusion 11 has a continuous loop shape when seen in a plan view, and seals the gap between the liquid crystal panel 1 and the outer case 7. For this reason, since the filler 15 having fluidity does not flow out toward the opening 10, it does not stain the image surface of the liquid crystal panel 1.

FIG. 2 shows the bottom shape of the liquid crystal display device shown in FIG. As described above, the bottom portion 9 of the outer case 7
An opening 10 is provided in the liquid crystal panel 1, and the image surface of the liquid crystal panel 1 is exposed. In the drawing, the alternate long and short dash line indicates the liquid crystal panel
3 shows the outer peripheral shape of the lower glass substrate 2 constituting the above. In addition, as shown by the dotted line, the protrusion 11 extends along the opening 10.
Is provided. The protrusion 11 has a continuous loop shape when seen in a 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 ceiling.

The outer case 7 is generally manufactured by molding a resin using a mold or the like. The smaller the width dimension of the protrusion 11, the more the contact pressure per unit area increases and the closer the contact with the glass substrate, the better. Further, the thinner the thinner, the easier the plastic deformation becomes, and the easier it becomes to fit the surface of the glass substrate 2. However, there is a limit to the width dimension of the protrusion 11 in terms of mold design or molding process, and a dimension of at least about 0.3 mm is required for stable molding. In addition, in order to support the liquid crystal panel 1 against the pressing force, the minimum width dimension of about 0.3 mm is also required.

[0015]

As described above, according to the present invention, a continuous loop-shaped projection is provided on the bottom of the outer case,
With this structure, the liquid crystal panel is supported. For this reason, the contact area can be made smaller than in the prior art, so that the pressing force per unit area is increased and the liquid crystal panel and the outer case can be integrated with high accuracy. In other words, since the protrusion has a function of absorbing the dimensional error, the dimensional error between the liquid crystal panel and the outer case can be tolerated. Further, 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 drawings]

FIG. 1 is a cross-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 showing 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]

 1 Liquid Crystal Panel 2 Glass Substrate 3 Glass Substrate 7 Exterior Case 8 Recess 9 Bottom 10 Opening 11 Protrusion 12 Lid Member 13 Flange 14 Screw 15 Filling Material

Claims (2)

[Claims] 1. A liquid crystal panel having a pair of substrates each having a transparent electrode on its inner surface and a liquid crystal layer sandwiched between the substrates,
In a liquid crystal display device including an outer case that holds the liquid crystal panel, the outer case has a protrusion such that a contact surface with a flat surface of the liquid crystal panel has a continuous loop shape, and is provided in a gap between the liquid crystal panel and the outer case. A liquid crystal display device characterized by arranging a filler. 2. The liquid crystal display device according to claim 1, further comprising a lid member that covers an opening surface of an outer case that holds the liquid crystal panel.