JP2001356334A - Direct vision type liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a direct vision type liquid crystal display device having a structure wherein not only the exchange of a polarizing plate can be easily performed but also a liquid crystal, a color filter glass plate, a TFT glass plate and the like are easily separated and recovered and from which the resources can be easily reused as a result. SOLUTION: The direct vision type liquid crystal display device 1A is constituted of a liquid crystal unit 15A and an another group. The liquid crystal unit 15A is integrally constituted of one surface of the color filter glass plate 11, the other surface of the TFT glass substrate 10 and the liquid crystal 12 sealed between them and having uniform thickness and a first polarizing plate 9A and a second polarizing plate 14A are disposed on the surface of the TFT glass plate 10 and the color filter glass plate 11, respectively, and at least the second polarizing plate 14A of the two polarizing plates is disposed without being stuck using any adhesive. The another group is constituted of a lens film 8, a diffusion plate 7, a light guiding plate 6, a light source L and the like which are disposed on the back side of the first polarizing plate 9A on the TFT glass plate 10 side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct-view type liquid crystal display device, and more particularly to a direct-view type liquid crystal display device having a mounting structure capable of easily removing a polarizing plate as a component thereof.

[0002]

2. Description of the Related Art First, a conventional liquid crystal display device will be described.

FIG. 3 is a cross-sectional side view showing the structure of a conventional direct-view type liquid crystal display device, FIG. 4 is a view showing a process of replacing a polarizing plate of the direct-view type liquid crystal display device shown in FIG. 3, and FIG. FIG. 6 is a perspective view showing a configuration of a projection type liquid crystal display device, and FIG.
FIG. 6 is a partial perspective view showing another replacement structure of the polarizing plate of the projection type liquid crystal display device shown in FIG. 5.

First, the configuration and structure of a direct-view type liquid crystal display device of a conventional liquid crystal display device will be described with reference to FIG.

[0005] Reference numeral 1 generally indicates a recent one-view type liquid crystal display device. The direct-view liquid crystal display device 1 is configured such that various components are stored in a flat rectangular parallelepiped case 2 in a state of being sequentially stacked. That is, the case 2 includes a case body 3 having a bottom and a lid 5 having an opening 4 largely opened at the center. It is fixed to each side by screwing or fixed by a hooking structure.

The light guide plate 6, the diffusion plate 7, the lens film 8, the TFT glass substrate 10 and the color filter glass plate 11 are sealed from the bottom inside the case body 3, and the periphery is sealed with a seal 13. Liquid crystal 12 and TF stopped
First polarizing plate 9 and color filter glass plate 11 adhered to the outer surface (lower surface in FIG. 3) of T glass plate 10
A liquid crystal unit 15 integrally formed with a second polarizing plate 14 attached to the outer surface (the upper surface in FIG. 3)
Are stacked, a fluorescent tube L is arranged on one side surface of the light guide plate 6, and the lid 5 is covered from above the case body 3 and sealed.

[0007] In this specification, a TFT is an abbreviation for a thin film transistor, and a TFT glass plate is composed of a plurality of pixel electrodes and a plurality of TFTs electrically connected to the pixel electrodes. It refers to a glass substrate having a formed pixel group region.

The state shown in the drawing is such that the structure of the plate body of each layer can be clearly understood, between the light guide plate 6 and the diffusion plate 7, between the diffusion plate 7 and the lens film 8, between the lens film 8 and the first polarizing plate 9. And a gap is provided between the second polarizer 14 and the inner peripheral surface of the upper surface of the lid 5, but the lid 5 slightly presses the second polarizer 14 so as to be in close contact with the second polarizer 14. The case body 3
It is fixed to.

On the other hand, for example, as shown in FIG. 5, a projection type liquid crystal display device 20 disclosed in Japanese Patent Laid-Open Publication No. Hei 6-18835 "Projection type liquid crystal display device" is capable of displaying a color image. A light source 21 for white light
, A condensing optical system 22, and three sets of liquid crystal display elements 23 (23
R, 23G, 23B) and a projection optical system 24. Each of the liquid crystal display elements 23 is a liquid crystal cell 2
3a is sandwiched between the incident side polarizing plate 23b and the projection side polarizing plate 23c, and the incident side polarizing plate 23b is supported so as to be detachable from the rotary polarizing plate support 25.
The rotating polarizing plate support 25 supports two polarizing plates.

By adopting such a polarizing plate supporting structure, the projection type liquid crystal display device 20 can rotate the polarizing plate when one of the incident side polarizing plates which is exposed to the strong irradiation light L and is easily deteriorated is deteriorated. This is a structure in which the support 25 is rotated and appropriately switched to the other polarizing plate for use.

One of the polarizing plates is, for example, 99.9.
% Polarization degree, a high polarization degree polarization plate with a transmittance of 38.5%,
The other polarizing plate is, for example, a high-transmitting polarizing plate having a degree of polarization of 99.5% and a transmittance of 44.5%. When the surroundings are dark, a high-polarizing degree polarizing plate is used. There is also disclosed a technique for switching to a polarizing plate.

Further, as shown in FIG.
3a is supported by a support frame 26, and a structure is adopted in which it is slid and inserted into and removed from a guide frame 27 which is open in the housing C, and a polarizing plate having a high degree of polarization and a polarizing plate having a high transmittance according to the surrounding brightness. There is also disclosed a technique for switching between the two.

As described above, most of the direct-view type liquid crystal display device 1 has a structure in which the polarizing plate 14 is exposed from the opening 4 of the lid 5 to the surface, and the surface of the polarizing plate 14 is made of cellulose acetate or the like. Which is soft and easily scratched.

Further, since the polarizing layer constituting the polarizing plate 14 is made of polyvinyl alcohol, it has a hygroscopic property, and its polarization performance is deteriorated after long-term use. As a result, the display quality is lowered.

Therefore, such a direct-view type liquid crystal display device 1
The liquid crystal unit 15 in has been
Although the life of the liquid crystal unit is dramatically extended, and it is generally considered to last for 7 to 8 years, if the liquid crystal unit 15 is damaged or deteriorated, it is currently disposed of as a life.

On the other hand, since the liquid crystal unit in the projection type liquid crystal display device 20 is originally constituted by a structure in which the incident side polarizing plate 23b is arranged to face the liquid crystal display element 23 and is separated from the liquid crystal display element 23, the liquid crystal unit is polarized. When the life of the board has expired due to deterioration or the like, it can be easily replaced.

[0017] By the way, wastes are piled up today and global environmental problems are becoming serious, and the shift from the conventional mass production and mass waste economic system to a resource recycling type economic system is a social issue. Has become an important issue. In order to build a resource-recycling economic system, it is necessary to actively promote the control of waste generation (reduction), reuse (reuse), and recycling (recycling).

On the other hand, with the rapid rise of the information network society in recent years, personal computers (hereinafter simply abbreviated as “PCs”) have rapidly spread to ordinary households. Therefore, the demand for so-called "notebook personal computers" using the direct-view type liquid crystal display device has been growing remarkably. In addition, the direct-view type liquid crystal display device is actively used in home electronic devices such as a home video camera and an electronic still camera, and the use thereof is expected to further increase in the future. Also, at present, these electronic devices are actively developing new technologies,
In particular, personal computers have undergone a few model changes within a year.

However, recent personal computer model changes mainly focus on upgrading the CPU and hard disk, and the direct-view type liquid crystal display device is SVGA (800 × 600).
Pixel), 10 in XGA (1024 × 768 pixel) mode
Since the 型 14 type is the mainstream and has a sufficient resolution for general use, no significant change is seen in the future. Further, as described above, the life of the liquid crystal unit of the direct-view type liquid crystal display device is remarkably increased due to recent technological advances, and it is considered that the liquid crystal unit usually has 7 to 8 years.
In other words, the reality is that the life of the product due to obsolescence is shorter than the life of the device.

Further, products using these direct-view type liquid crystal display devices are actually landfilled without being reused when they are used and discarded. Not good for the environment.

Further, the direct-view type liquid crystal display device is produced by the advanced semiconductor production technology, and the energy involved in the production is enormous. Therefore, reusing the energy as much as possible results in the generation of carbon dioxide which causes global warming. It also leads to suppression.

This problem can be similarly applied to the liquid crystal display element 23 and the polarizing plate 23b of the projection type liquid crystal display device 20, but their numbers are incomparably small.
However, although the publication does not refer to regeneration or reuse, if it is discarded without regeneration or reuse as in the past, both from the viewpoint of the global environment and the protection of resources, Not preferred.

At present, almost all of the polarizing plates are supplied in a state in which an adhesive is applied from a manufacturer thereof, as a factor that hinders the reuse of the direct-view type liquid crystal display device. Color filter glass plate 11 and T
Attachment (or attachment) attached to the FT glass plate 10
There is a problem in the structure, and it is difficult to perform the replacement work easily.

This replacement of the polarizing plate 14 in the prior art direct-view type liquid crystal display device 1 involves the steps shown in FIG. That is, first, the lid 5 is removed (ST
1) The liquid crystal unit 15 is taken out of the case body 3 (ST2), and the second polarizing plate 14 is
(ST3), the adhesive attached to the surface of the color filter glass plate 11 is wiped off with alcohol or the like (ST4), and the new second polarizing plate 14 is further removed. Before sticking, the surface of the color filter glass plate 11 is wiped with alcohol or the like and cleaned (ST5), and then a new second polarizing plate 14 is stuck on the surface of the color filter glass plate 11,
A new liquid crystal unit 15 is formed (ST6), and the liquid crystal unit 15 is assembled at the original position of the case main body 3 (ST7). Thereafter, the lid 5 is attached to the case main body 3 (ST8), and is replaced with a new second polarizing plate 14. After assembling as the direct-view liquid crystal display device 1, it is inspected whether an image can be projected normally (ST9), the inspection is passed, and the reproduction direct-view liquid crystal including the new second polarizing plate 14 is passed. The display device 1 is obtained.

[0025]

However, since the polarizing plate is weak to organic solvents such as alcohol, it is difficult to wipe off dirt and clean it.

The polarizing plate 14 is strongly adhered to the color filter glass plate 11 constituting the liquid crystal display element with an adhesive, and when the polarizing plate 14 is peeled off, the color filter glass plate 11 and the liquid crystal display element are removed. There is a great risk of damaging the product.

Further, the peeled-off second polarizing plate 14 is discarded as it is.

The present invention is intended to solve these problems in a direct-view type liquid crystal display device, and as in a projection type liquid crystal display device, the polarizer can be replaced very easily.
Besides, liquid crystal, color filter glass plate, TFT
An object of the present invention is to provide a direct-view type liquid crystal display device having a structure in which a glass plate or the like can be easily separated and collected, and resources can be easily reused.

[0029]

According to the first aspect of the present invention, a direct-view type liquid crystal display device includes a color filter glass plate on one side and a TFT glass plate on the other side, and a uniform glass plate between them. The liquid crystal is sealed at a small thickness and integrally formed, and a first polarizing plate and a second polarizing plate are provided on the surface of the TFT glass plate and the color filter glass plate, respectively. A liquid crystal unit provided at least without the second polarizing plate attached thereto;
The above problem is solved by comprising a lens film, a diffusion plate, a light guide plate, a light source, and the like behind the polarizing plate on the FT glass plate side.

According to a second aspect of the present invention, the thickness of the polarizing plate on the side of the color filter glass plate in the direct-view type liquid crystal display device according to the first aspect is substantially the same as the thickness of the polarizing plate. Is provided.

According to the third aspect of the present invention, in the direct-view type liquid crystal display device according to the first aspect, the polarizing plate on the color filter glass plate side is provided on the surface of the color filter glass plate, and the TFT glass plate is provided. The polarizing plate on the side is provided separately without being attached to the surface of the TFT glass plate.

Further, in the invention according to claim 4, the direct-view type liquid crystal display device is a case in which an opening is opened in a case main body and a central portion, and a lid of the case main body is provided. A light source, a light guide plate for guiding light from the light source, a diffusion plate, a lens film, and a first polarizing plate whose side end surface is surrounded by a spacer having a thickness substantially equal to that of the light source, from the inner bottom surface of the main body; A liquid crystal sealed in a space of uniform thickness formed by a TFT glass plate and a color filter glass plate facing the TFT glass plate on the first polarizing plate side, and the liquid crystal having the same thickness on the color filter glass plate side. A liquid crystal unit composed of a second polarizing plate having a side end surface surrounded by a spacer having a thickness, and a cover glass plate disposed on the second polarizing plate side and so as to cover the opening are sequentially arranged. Arranged and sealed with the lid It solves the problems.

Therefore, according to the first aspect of the present invention,
The polarizers disposed on both the front and back surfaces of the liquid crystal unit in the direct-view type liquid crystal display device can be replaced very easily.

According to the second aspect of the present invention,
In addition to the operation of the direct-view type liquid crystal display device according to claim 1,
The positioning of each polarizing plate with respect to the liquid crystal unit can be easily performed by each spacer.

According to the third aspect of the present invention, in addition to the operation of the direct-view type liquid crystal display device according to the first aspect, all the constituent members are made of a material when the direct-view type liquid crystal display device is disposed of. Each type can be collected separately.

According to the fourth aspect of the present invention, the polarizers disposed on both the front and back surfaces of the liquid crystal unit in the direct-view type liquid crystal display device can be exchanged extremely easily. The positioning of each of the polarizing plates with respect to can be easily performed.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A direct-view type liquid crystal display device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional side view showing the structure of a direct-view type liquid crystal display device according to an embodiment of the present invention, and FIG. 2 is a process chart for replacing a polarizing plate of the direct-view type liquid crystal display device shown in FIG. is there.

The same components as those of the direct-view type liquid crystal display device 1 of the prior art shown in FIG.

In FIG. 1, reference numeral 1A generally indicates a direct-view type liquid crystal display device according to an embodiment of the present invention. This direct-view type liquid crystal display device 1A is also incorporated in a flat rectangular parallelepiped case 2 similarly to the conventional direct-view type liquid crystal display device 1, and the case 2 has a bottomed case body 3 and an opening at the center. 4 comprises a lid 5 which is widely opened,
The lid 5 is fixed to each side surface of the case body 3 by screwing, or is fixed by a hooking structure in a state in which constituent elements described later are stored.

A fluorescent tube L as a light source, a light guide plate 6 for guiding light from the fluorescent tube L, a diffusing plate 7, and a lens film 8 are sequentially arranged inside the case body 3 from the bottom thereof.
The direct-view type liquid crystal display device 1 of the prior art is provided.
The structure is the same as

On the lens film 8, a liquid crystal unit 15A, which is a feature of the present invention, is provided. That is, the liquid crystal unit 15A is provided with the first polarizing plate 9A.
And a spacer 9B having a thickness substantially equal to the thickness of the first polarizing plate 9A disposed so as to surround the side end face thereof, and a TFT glass plate 10 and a color filter facing the TFT glass plate 10 on the first polarizing plate 9A. Liquid crystal 12 sealed with a seal 13 in a space having a uniform thickness formed by the glass plate 11 and a spacer 14B having a thickness almost the same on the color filter glass plate 11 side are surrounded by side end faces. Second polarizing plate 14
A.

On the second polarizing plate 14A, a cover glass plate 16 having an area larger than the area of the opening 4 of the lid 5 is disposed so as to cover the whole of the components thus stacked in this order. It is configured to be closed by the lid 5, engaged with the case body 3, and sealed by means such as screwing.

The state shown in the figure is such that the configuration of the plate body of each element is clearly understood, between the light guide plate 6 and the diffusion plate 7, between the diffusion plate 7 and the lens film 8, between the lens film 8 and the first polarizing plate. 9
A, between the first polarizing plate 9A and the TFT glass plate 10, and between the second polarizing plate 14A, the lid 5 and the cover glass plate 1.
6 are shown with a gap therebetween, but in practice, the cover glass plate 16 fixed to the inner surface of the lid 5 so that they are in close contact with each other slightly presses the second polarizing plate 14A. The lid 5 is fixed to the case body 3.

As shown, the direct-view type liquid crystal display device 1
In A, the first polarizing plate 9A is not attached to the TFT glass plate 10 with an adhesive, and the second polarizing plate 14A is not attached to the color filter glass plate 11 with an adhesive. However, the first polarizing plate 9A and the second polarizing plate 14A are positioned at predetermined positions by the spacers 9B and 14B, respectively.

By adopting such a configuration and structure,
The direct-view type liquid crystal display device 1A of the present invention includes a second polarizing plate 14A.
In the case where is deteriorated, as shown in FIG. 2, the lid 5 is removed from the case main body 3 (ST1), the second polarizing plate 14A is removed from the case main body 3, and a new second polarized light prepared in advance is prepared. The plate 14A is mounted and replaced (ST2). After the replacement of the second polarizing plate 14A, the cover 5 is attached and fixed in the same manner as described above (ST3), so that a new second
The direct-view type liquid crystal display device 1A having the polarizing plate 14A can be reassembled, and the same inspection as described above is performed (ST4) to obtain a reproduction direct-view type liquid crystal display device 1A that conforms to a predetermined standard. Can be. As described above, according to the present invention, the extremely simple and easily degraded second
The polarizing plate 14A can be replaced.

Also, as in the above embodiment, the first polarizing plate 9
A, if the second polarizing plate 14A is separate, the liquid crystal sealed with the TFT glass plate 10, the color filter glass plate 11, and the seal 13 in addition to the lid 5 and the second polarizing plate 14A By removing the liquid crystal element composed of 12, both the first polarizing plate 9A and the second polarizing plate 14A can be easily removed, and when the direct-view type liquid crystal display device 1A is discarded, it is easy to sort by material. And the material can be easily regenerated. Example 1 A comparison was made between a conventional personal computer and a notebook computer equipped with a 10.4-inch SVGA type direct-view liquid crystal display device for reusing the conventional technology and the direct-view liquid crystal display device of the present invention.

As a result, the second polarizing plate 1 according to the prior art
4 took 7.1 minutes, while the replacement time of the second polarizer 14A in the direct-view type liquid crystal display device 1A of the present invention was 1.8 minutes, which was smaller than that of the conventional structure. The replacement work time was reduced to about 1/4, and the effect was confirmed. Example 2 A comparison was made between a notebook computer having a 14.1 type XGA type direct-view type liquid crystal display device and a conventional personal computer and a work for reusing the direct-view type liquid crystal display device having the structure of the present invention.

As a result, the second polarizing plate 1 according to the prior art
4 took 11.4 minutes, whereas the replacement time of the second polarizer 14A in the direct-view type liquid crystal display device 1A of the present invention was 2.2 minutes, which was smaller than that of the conventional structure. The replacement work time was reduced to about 1/5, and the effect was confirmed. [Example 3] A comparison was made between a conventional video camera and a home video camera equipped with a 3.0-inch 180,000-pixel direct-view liquid crystal display device for reusing the conventional and direct-view liquid crystal display devices of the present invention.

As a result, the second polarizing plate 1 of the prior art
4 took 3.8 minutes, while the replacement time of the second polarizer 14A in the direct-view type liquid crystal display device 1A of the present invention was 1.3 minutes, which was smaller than that of the conventional structure. The replacement work time was reduced to about 1/3, and the effect was confirmed.

[0051]

As described above, according to the direct-view liquid crystal display device of the present invention, the (second) polarizing plate replacement work time is reduced from about 1/3 to 1/5 of that of the prior art. In addition, the risk of damage to the liquid crystal and glass accompanying the replacement work of the polarizing plate can be avoided, and the material can be easily sorted at the time of disposal of the direct-view type liquid crystal display device. Numerous excellent effects can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional side view showing a configuration of a direct-view type liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a process chart for exchanging a polarizing plate of the direct-view type liquid crystal display device shown in FIG.

FIG. 3 is a cross-sectional side view showing a configuration of a conventional direct-view type liquid crystal display device.

FIG. 4 is a process diagram for exchanging a polarizing plate of the direct-view type liquid crystal display device shown in FIG. 3;

FIG. 5 is a perspective view showing a configuration of a conventional projection type liquid crystal display device.

FIG. 6 is a partial perspective view showing another replacement structure of the polarizing plate of the projection type liquid crystal display device shown in FIG.

[Explanation of symbols]

1A: Direct-view type liquid crystal display device according to one embodiment of the present invention;
Case, 3 ... Case body, 4 ... Opening, 5 ... Lid, 6 ...
Light guide plate, 7: diffusion plate, 8: lens film, 9A: first
Polarizing plate, 9B: spacer, 10: TFT glass plate, 11
... color filter glass plate, 12 ... liquid crystal, 14A ... second polarizing plate, 14B ... spacer, 15A ... liquid crystal unit,
16 ... Cover glass plate

Claims (4)

[Claims] 1. A glass plate having a color filter substrate on one side and a glass plate having a thin film transistor on the other side, wherein a liquid crystal is sealed with a uniform thickness between the two and integrally formed, and the thin film transistor is provided. And a liquid crystal unit in which a first polarizing plate and a second polarizing plate are respectively provided on the surface of the color filter glass plate, and at least the second polarizing plate is provided without being attached thereto. Behind the polarizing plate on the glass plate side having the thin film transistor, a lens film, a diffusion plate, a light guide plate,
A direct-view liquid crystal display device comprising a light source and the like. 2. The direct view according to claim 1, wherein a spacer having a thickness substantially equal to the thickness of the polarizing plate is provided on a side end surface of the polarizing plate on the color filter glass plate side. Liquid crystal display device. 3. The polarizing plate on the color filter glass plate side is adhered to the surface of the color filter glass plate, and the polarizing plate on the glass plate side having the thin film transistor is adhered to the surface of the glass plate having the thin film transistor. The direct-view type liquid crystal display device according to claim 1, wherein the direct-view type liquid crystal display device is provided separately without being provided. 4. A light source and a light guide for guiding light from the light source from an inner bottom surface of the case main body of a case formed of a case main body and a central portion, the opening being opened at a central portion of the case main body. A light plate, a diffusion plate, a lens film, a first polarizing plate whose side end surface is surrounded by spacers having substantially the same thickness, and a glass plate having a thin film transistor on the first polarizing plate side and facing the glass plate A liquid crystal sealed in a space having a uniform thickness formed by a color filter glass plate, and a side end surface surrounded by spacers having substantially the same thickness on the color filter glass plate side; A liquid crystal unit composed of a second polarizing plate disposed without being attached to a plate, and a cover glass plate disposed on the side of the second polarizing plate and covering the opening. Arranged in sequence, with the lid A direct-view type liquid crystal display device characterized by being enclosed.