JP2002366046A - Display device and projection device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use one kind of an adhesive, to improve the adhesion strength and to obtain excellent heat radiating property and moisture-proof property. SOLUTION: A liquid crystal panel 102 and dust preventing glasses 105, 106 are stacked and housed in a case 101. The liquid crystal panel 102 and the dust preventing glasses 105, 106, and the inner walls 112 of the case 101 and all of the side faces of the liquid crystal panel 102 and the glasses 105, 106 are integrally adhered with an adhesive 110. Thus, extremely strong adhesion strength can be obtained. Since spaces in the case 101 are filled with the adhesive 110, the heat radiation property and moisture-proof property can be also improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device using a flexible printed circuit board which is positioned by image recognition and is connected by pressure bonding using an anisotropic conductive film.

[0002]

2. Description of the Related Art A liquid crystal device such as a liquid crystal light valve is constructed by sealing a liquid crystal between two substrates such as a glass substrate and a quartz substrate. In a liquid crystal light valve, for example, a thin film transistor (hereinafter, referred to as T
Active elements such as FT) are arranged in a matrix, opposing electrodes are arranged on the other substrate, and the optical characteristics of the liquid crystal layer sealed between the two substrates are changed according to image signals.
Enable image display.

That is, an image signal is supplied to pixel electrodes (ITO) arranged in a matrix by TFT elements, and a voltage based on the image signal is applied to a liquid crystal layer between the pixel electrode and the counter electrode, thereby forming a liquid crystal molecule. Change the sequence. Thus, the image display is performed by changing the transmittance of the pixel and changing the light passing through the pixel electrode and the liquid crystal layer according to the image signal.

[0004] A TFT substrate on which TFTs are arranged and an opposing substrate arranged opposite to the TFT substrate are manufactured separately.
After both substrates are bonded with high precision in a panel assembly process, liquid crystal is sealed.

In the panel assembling process, first, an alignment film is formed on the surface of the TFT substrate and the counter substrate which are manufactured in each substrate process, that is, on the surface in contact with the liquid crystal layer of the counter substrate and the TFT substrate. Next, a rubbing process is performed. Next, a seal portion serving as an adhesive is formed on one edge of one substrate. The TFT substrate and the opposing substrate are bonded to each other using a sealing portion, and are pressure-bonded and cured while performing alignment. A cutout is provided in a part of the seal portion, and the liquid crystal is sealed through the cutout.

In a region outside the seal portion of the TFT substrate,
Mounting terminals for transmitting and receiving drive signals, timing signals, image signals, and the like for the liquid crystal panel are arranged between various drive circuits on the panel and external devices. An FPC (flexible printed board) is adopted for connection with an external device.
The mounting terminal and the FPC are connected to the ACF (An
Pressure bonding using isotoropic conductive film (anisotropic conductive film).

Incidentally, a liquid crystal panel is sometimes used for a projector. In a projector, an image on a screen of a liquid crystal panel is enlarged and projected on the screen. Therefore, when dust adheres to the screen of the liquid crystal panel, the quality of the displayed image is significantly deteriorated due to the influence of the dust. Therefore,
In order to reduce the influence of dust and the like, dustproof glass is attached to the entrance surface and the exit surface of the liquid crystal panel, and the dustproof glass and the liquid crystal panel are stacked and stored in a case.

FIG. 6 is an explanatory view showing a state in which a laminate of a liquid crystal panel to which an FPC is attached and dustproof glass is housed in a case. FIG. 6A shows a planar shape, and FIG.
(B) shows the shape of the cross section.

The case 81 is a housing having an open upper surface.
The inside substantially conforms to the shapes of the laminated dust-proof glasses 85 and 86 and the liquid crystal panel 82. A dustproof glass 85 is placed on the bottom of the case 81. An adhesive 87 is applied on the dust-proof glass 85, and the adhesive 87
And the opposing substrate 84 of the liquid crystal panel 82 are bonded.

Further, an adhesive 88 is embedded in a gap between the horizontal side surfaces 91 of the element substrate 83 and the opposing substrate 84 of the liquid crystal panel 82 and the inner wall 92 of the case 81 to adhere the liquid crystal panel 82 to the case 81. It is designed to be fixed. An adhesive 89 is applied on the element substrate 83 of the liquid crystal panel 82, and the element substrate 83 and the dustproof glass 86 are adhered by the adhesive 89.

A liquid crystal panel 82 is provided at the center of the bottom of the case 81.
An opening 93 is formed corresponding to the effective display area of the liquid crystal panel 82 from the counter substrate 84 side of the liquid crystal panel 82 through the dustproof glass 85.
And is emitted through the dustproof glass 86. In addition,
An FPC 94 is crimped and fixed to a mounting terminal provided at an end of the element substrate 83 of the liquid crystal panel 82.

[0012]

The case 81
When the liquid crystal substrate 82 and the dust-proof glasses 85 and 86 are adhered and fixed therein, the opposing substrate 84, the element substrate 83 and the dust-proof glass 8 are taken into consideration, for example, when the adhesive is oozed out.
Adhesives 87 and 88 for bonding the liquid crystal substrate 8 and the liquid crystal substrate 8
Two kinds of adhesives are required, namely, an adhesive 82 for bonding the 2 to the case 81.

The liquid crystal panel 82 and the dustproof glasses 85 and 86
And the case 81, the side surface 91 of the liquid crystal panel 82 and the inner wall 9
2 and is fixed only by the adhesive 88 between them. For this reason, the liquid crystal panel 82 and the dustproof glasses 85, 8
6 has a problem that the fixing strength in the case 81 is relatively weak.

By the way, in projectors, higher luminance has been promoted. LCD panel 8
The heat generated in 2 etc. is also large. The heat generated in the liquid crystal panel 82 and the dustproof glasses 85 and 86 is radiated through the case 81. However, the case 81 and the liquid crystal panel 8
There is a problem that air intervenes most of the space between the dust-proof glass 2 and the dust-proof glasses 85 and 86, and the heat radiation effect is poor.

The liquid crystal panel 82 and the dustproof glass 8
There is also a problem that there are many gaps between the 5, 86 and the case 81, moisture easily enters the liquid crystal panel 82, and the moisture proof property is poor. Further, there is a problem that the fixing strength of the flexible printed board fixed by pressure to the liquid crystal panel 82 is not sufficient. Further, there is also a problem that the adhesives 87 and 89 may ooze out and hinder the curing of the adhesive 88.

The present invention has been made in view of such a problem, and reduces the kind of necessary adhesive by integrally using one kind of adhesive and filling all gaps with the case. And a projection device using the same.

Further, the present invention provides a method in which one kind of adhesive is integrated and used to fill all the gaps with the case.
An object of the present invention is to provide a display device capable of improving the bonding strength and a projection device using the same.

Further, the present invention provides a method in which one kind of adhesive is integrated and used to fill all the gaps with the case.
It is an object of the present invention to provide a display device capable of improving heat dissipation and a projection device using the same.

Also, the present invention provides a method in which one kind of adhesive is integrated and used to fill all the gaps with the case.
It is an object of the present invention to provide a display device capable of improving a moisture-proof effect and a projection device using the same.

Further, the present invention provides a method in which one kind of adhesive is integrated and used to fill all the gaps with the case.
An object of the present invention is to provide a display device capable of improving the fixing strength of a flexible printed board and a projection device using the same.

[0021]

According to the present invention, there is provided a display device comprising: a display panel; two dust-proof glasses disposed on an entrance surface and an exit surface of the display panel; The display panel, the display panel being provided integrally between the display panel and the two dust-proof glasses, and between the display panel and the two dust-proof glasses and the inner wall of the case. And the two dustproof glasses are adhered and fixed, and the display panel and 2
An adhesive for adhering and fixing a sheet of dustproof glass in the case.

According to such a configuration, the display panel and the two
It is glued and fixed with an adhesive between the pieces of dustproof glass,
The display panel, the two dustproof glasses, and the inner wall of the case are also adhesively fixed with an adhesive. The adhesive used for these adhesive fixing is provided integrally, and has high adhesive strength. Therefore, there is no displacement of the display panel in the case.

[0023] The adhesive may be integrally filled in all the gaps in the case.

According to such a configuration, since the adhesive is integrally filled in all the gaps in the case, the adhesive strength is extremely high, and the display panel and the two dustproof glasses are securely fixed in the case. Is done. Further, since there is no gap in the case, moisture is not mixed and the moisture proof property is excellent, and the heat generated in the display panel and the two dustproof glasses is efficiently radiated from the case to the outside, so that the heat radiating property is excellent.

The display device according to the present invention further comprises a flexible substrate connected and fixed to the display panel, wherein the adhesive is also filled around the flexible substrate in the case. .

According to such a configuration, the periphery of the flexible substrate connected to the display panel is filled with an adhesive, and is firmly adhered and fixed in the case.

A projection device according to the present invention is characterized by using the above-mentioned display device.

According to such a configuration, since the position of the display panel in the case is prevented from being shifted, the display panel can be reliably positioned by fixing the case to the projection device housing.

[0029]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows the first embodiment of the present invention.
It is an explanatory view showing a display concerning an embodiment. This embodiment is an example in which the present invention is applied to a liquid crystal display device as a display device. FIG. 2 is an equivalent circuit diagram of various elements, wiring, and the like in a plurality of pixels constituting a pixel region of the liquid crystal device. FIG. 3 is a plan view of an element substrate such as a TFT substrate as viewed from a counter substrate side together with components formed thereon, and FIG. 4 is an assembly process of bonding the element substrate and the counter substrate to seal liquid crystal. FIG. 4 is a cross-sectional view of the liquid crystal device after completion, cut along the line HH ′ in FIG. 3. FIG. 5 is a cross-sectional view showing the liquid crystal device in detail.

First, the structure of the liquid crystal panel will be described with reference to FIGS.

As shown in FIG. 3 and FIG. 4, the liquid crystal panel is formed by sealing a liquid crystal 50 between an element substrate 10 such as a TFT substrate and a counter substrate 20. Pixel electrodes and the like constituting pixels are arranged in a matrix on the element substrate 10. FIG. 2 shows an equivalent circuit of an element on the element substrate 10 constituting a pixel.

As shown in FIG. 2, in the pixel area,
A plurality of scanning lines 3a and a plurality of data lines 6a are wired so as to intersect, and pixel electrodes 9a are arranged in a matrix in a region defined by the scanning lines 3a and the data lines 6a. Then, a TFT 30 is provided at each intersection of the scanning line 3a and the data line 6a, and the pixel electrode 9a is connected to the TFT 30.

The TFT 30 is turned on by the ON signal of the scanning line 3a, whereby the image signal supplied to the data line 6a is supplied to the pixel electrode 9a. This pixel electrode 9
a and a voltage between the counter electrode 21 provided on the counter substrate 20 is applied to the liquid crystal 50. In addition, a storage capacitor 70 is provided in parallel with the pixel electrode 9a, and the storage capacitor 70 allows the voltage of the pixel electrode 9a to be held for a period of time, for example, three digits longer than the time during which the source voltage is applied. The storage capacitor 70 improves the voltage holding characteristics and enables an image display with a high contrast ratio.

FIG. 5 is a schematic sectional view of a liquid crystal panel focusing on one pixel.

The element substrate 10 made of glass, quartz, etc.
A TFT 30 having a D structure is provided. TFT30
Is provided with a scanning line 3a forming a gate electrode via an insulating film 2 in a semiconductor layer in which a channel region 1a, a source region 1d, and a drain region 1e are formed. The data line 6a is stacked on the TFT 30 via the first interlayer insulating film 4,
Data line 6a is electrically connected to source region 1d via contact hole 5. The pixel electrode 9a is stacked on the data line 6a via the second interlayer insulating film 7, and the pixel electrode 9a is electrically connected to the drain region 1e via the contact hole 8.

When an ON signal is supplied to the scanning line 3a (gate electrode), the channel region 1a becomes conductive,
The source region 1d and the drain region 1e are connected, and the image signal supplied to the data line 6a is given to the pixel electrode 9a.

In the semiconductor layer, a storage capacitor electrode 1f extending from the drain region 1e is formed. The storage capacitor electrode 1f is connected to a capacitor line 3b via an insulating film 2 which is a dielectric film.
Are arranged opposite to each other, thereby forming the storage capacitor 70. An alignment film 16 made of a polyimide-based polymer resin is laminated on the pixel electrode 9a and rubbed in a predetermined direction.

On the other hand, the opposing substrate 20 is provided with a first light-shielding film 23 in a region facing the data line 6a, the scanning line 3a and the TFT 30 in the TFT array substrate, that is, in a non-display region of each pixel. . The first light-shielding film 23 allows incident light from the counter substrate 20 to be transmitted to the channel region 1a, the source region 1d, and the drain region 1e of the TFT 30.
Is prevented from entering. An opposing electrode (common electrode) 21 is formed over the entire surface of the substrate 20 on the first light-shielding film 23. An alignment film 22 made of a polyimide polymer resin is laminated on the counter electrode 21 and rubbed in a predetermined direction.

The liquid crystal 50 is sealed between the element substrate 10 and the counter substrate 20. Thereby, TFT3
0 writes the image signal supplied from the data line 6a to the pixel electrode 9a at a predetermined timing. In accordance with the written potential difference between the pixel electrode 9a and the counter electrode 21, the orientation and order of the molecular assembly of the liquid crystal 50 are changed, thereby modulating light and enabling gradation display.

As shown in FIG. 3 and FIG.
Is provided with a second light shielding film 42 as a frame for partitioning the display area. The second light shielding film 42 is, for example, the first light shielding film 2
3 is made of the same or different light-shielding material.

A sealing material 41 for sealing liquid crystal is formed between the element substrate 10 and the counter substrate 20 in a region outside the second light-shielding film 42. The sealing material 41 is disposed so as to substantially match the contour shape of the counter substrate 20, and fixes the element substrate 10 and the counter substrate 20 to each other. The sealing material 41 is used for the element substrate 1.
The liquid crystal 5 is missing in a part of one side of the substrate 0 and the gap between the bonded element substrate 10 and the opposing substrate 20.
A liquid crystal injection port 78 for injecting 0 is formed. After the liquid crystal is injected from the liquid crystal injection port 78, the liquid crystal injection port 78 is sealed with a sealing material 79.

In a region of the element substrate 10 outside the seal member 41, a data line driving circuit 61 and mounting terminals 62 are provided along one side of the element substrate 10, and along two sides adjacent to this one side. , A scanning line driving circuit 63 is provided. On one remaining side of the element substrate 10, a plurality of wirings 64 for connecting the scanning line driving circuits 63 provided on both sides of the screen display area are provided. In at least one of the corners of the opposing substrate 20, the element substrate 1
A conductive member 65 is provided for electrically connecting the first substrate 0 to the counter substrate 20.

The element substrate 10 and the counter substrate 20 are manufactured separately and assembled into a panel in an assembly process. That is, polyimide (PI) that will be the alignment films 16 and 22 is applied to the prepared element substrate 10 and counter substrate 20 respectively. Next, with respect to the alignment film 16 on the surface of the element substrate 10 and the alignment film 22 on the surface of the counter substrate 20,
A rubbing treatment is performed.

Next, a cleaning step of removing dust generated by the rubbing process is performed. When the cleaning step is completed, the sealing material 41 and the conductive material 65 (see FIG. 3) are formed.
After forming the sealing material 41, the element substrate 10 and the opposing substrate 2
And then press-fit while aligning.
The sealing material 41 is cured. Finally, a liquid crystal is sealed from a notch provided in a part of the sealing material 41, and the liquid crystal is sealed by closing the notch.

The liquid crystal panel thus constructed is provided with an FPC.
Is connected, and dustproof glass is laminated and stored in a case.
FIG. 1 shows this state, in which FIG. 1A shows a planar shape, and FIG. 1B shows a cross-sectional shape of FIG. 1A.

The liquid crystal panel 102 shown in FIG.
The element substrate 103 and the opposing substrate 10
4 are bonded together. LCD panel 102
The FPC 114 is connected to the mounting terminal 62 (see FIG. 3). The FPC 114 is a copper foil pattern (not shown) made of, for example, a rolled copper foil on a base material such as a polyimide film.
And a cover material is formed on the copper foil pattern. The copper foil patterns are juxtaposed along the longitudinal direction of the FPC 114. ACF (not shown), which is an adhesive containing conductive particles, is provided in the width direction of the FPC 114.
Are formed, and the FPC 114 is formed by using the ACF.
Are fixed on the element substrate 103 by pressure bonding.

Dust-proof glasses 106 and 105 are disposed on the element substrate 103 and the counter substrate 104 of the liquid crystal panel 102, respectively. A part 107 of the adhesive 110 is interposed between the counter substrate 104 and the dustproof glass 105, and the adhesive 110
Is bonded to the opposing substrate 104 and the dust-proof glass 105. The element substrate 103 and the dustproof glass 106
A part 108 of the adhesive 110 intervenes between the element substrate 103 and the dustproof glass 1.
06.

The inside of the case 101 is formed in a shape substantially matching the shape of the dustproof glass 105, the liquid crystal panel 102, and the dustproof glass 106.

In this embodiment, a gap between the horizontal and vertical side surfaces 111 of the laminated liquid crystal panel 102 and the dustproof glasses 105 and 106 and the omni-directional inner wall 112 of the case 101 is provided in the gap. Of the adhesive 110 is adhesively fixed between the entire side surface 111 of the liquid crystal panel 102 and the dustproof glasses 105 and 106 and the entire inner wall 112 of the case 101. I have.

The side wall of the case 101 facing the vertical side surface of the liquid crystal panel 102 is wider than the other side walls, and one of the wide side walls is attached to the element substrate 103. A step 115 having a thickness corresponding to the thickness of the dust-proof glass 105 and the counter substrate 104 is formed so that the FPC 114 is installed inside and outside the case 101 without bending. The step 115 is configured to be slightly wider than the width of the FPC 114 in the direction along the side wall.

Above the step 115 along the outer wall of the case 101, there is provided an embedding member 116 for filling the step of the step 115. The embedding member 116 is provided with the FPC 114 interposed between the FPC 114 and the upper surface of the step portion 115.
5 is detachable.

In this embodiment, the adhesive 110
The components 107, 108, and 113 are integrally applied (formed) to form a gap between the liquid crystal panel 102 and the dustproof glass 105, a gap between the liquid crystal panel 102 and the dustproof glass 106, and the liquid crystal panel 102 and the dustproof. Glass 105,
All gaps between all the side surfaces 111 of the case 106 and all the inner walls 112 of the case 101 are filled.

As the adhesive 110, a transparent adhesive having a higher viscosity than the conventional adhesive for dustproof glass, but having a relatively low viscosity is used. The adhesive 11
0 is preferably a silicone adhesive having some elasticity even when cured.

The case 101 has a liquid crystal panel 102
The opening 117 corresponding to the effective display area is formed.

Next, the assembling work of the display device of FIG. 1 will be described.

The FPC 114 is attached to the liquid crystal panel 102 having the same configuration as the liquid crystal panel shown in FIGS. For example, the position of a mark (not shown) on the liquid crystal panel 102 and a recognition mark (not shown) on the FPC 114 are detected by image recognition or the like, and the liquid crystal panel 102 and the FPC 11 are detected.
4 is aligned. Then, at a position where the copper foil pattern of the FPC 114 is connected to the corresponding mounting terminal 62, the FPC 114 is fixed on the element substrate 103 by crimping using an ACF.

Next, the opening 11 is formed on the bottom of the case 101.
The dustproof glass 105 is placed so as to close the block 7. Then
An appropriate amount of the adhesive 110 is filled. When the surface of the dust-proof glass 105 and the side surface 111 of the dust-proof glass 105 are substantially filled with the adhesive 110, the liquid crystal panel 102 is placed on the dust-proof glass 105 with the opposing substrate 104 facing down.

In this state, the embedding member 116 is
It is attached with the FPC 114 interposed therebetween.

While taking an appropriate time, an appropriate amount of the adhesive 110 is further filled. When the adhesive 110 is substantially filled on the element substrate 103 and the side surface 111 of the element substrate 103, the dustproof glass 106 is placed. Further, the liquid crystal panel 102 and the dustproof glasses 105 and 10 are filled with an adhesive 110.
The gap between all the side surfaces 111 of the sixth and the inner walls 112 of the case 101 is filled with the adhesive 110.

The adhesive 110 flows to the wall surface of the embedding member 116, and in the case 101, the FPC 114
Is filled in all the gaps, including the surrounding area.

As described above, in the present embodiment, one kind of the adhesive 110 is integrated and filled in all the gaps between the liquid crystal panel 102 and the dustproof glasses 105 and 106 and the case 101. The bonding strength between the liquid crystal panel 102, the dustproof glasses 105 and 106, and the case 101 is extremely high, and the liquid crystal panel 102 does not shift with respect to the case 101.

Since the adhesive 110 is also filled around the FPC 114 in the case 101,
The bonding strength of 114 is also very strong. Further, only one kind of adhesive is required, and work and management become easy.

Further, unlike the case where a plurality of types of adhesives are used, curing is not hindered by other adhesives.

The liquid crystal panel 102 and the dustproof glass 1
Numerals 05 and 106 are adhered to the case 101 via an adhesive 110, and the liquid crystal panel 102 and the dustproof glass 10 are attached.
The heat generated in 5, 106 is efficiently transmitted to case 101. Thereby, a high heat radiation effect can be obtained.

Since there is no gap in the case 101, moisture does not enter the case 101, and the case 101 is excellent in moisture proofness.

[0066]

As described above, according to the present invention, one kind of adhesive is integrated and used to fill all the gaps with the case, so that the kind of adhesive required is reduced and the adhesive strength is reduced. This has the effect of improving the heat dissipation and moisture proofing effects and improving the fixing strength of the flexible printed board.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a display device according to a first embodiment of the present invention.

FIG. 2 is an equivalent circuit diagram of various elements, wiring, and the like in a plurality of pixels forming a pixel region of the liquid crystal device.

FIG. 3 is a plan view of an element substrate such as a TFT substrate as viewed from a counter substrate side together with components formed thereon.

FIG. 4 is a cross-sectional view of the liquid crystal device after the assembly step of bonding an element substrate and a counter substrate and enclosing liquid crystal after completion of the assembly process, taken along the line HH ′ in FIG. 3;

FIG. 5 is a cross-sectional view illustrating a liquid crystal device in detail.

FIG. 6 is an explanatory diagram showing a conventional display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 ... Case 102 ... Liquid crystal panel 103 ... Element substrate 104 ... Counter substrate 105, 106 ... Dustproof glass 110 ... Adhesive 111 ... Side surface 112 ... Inner wall 114 ... FPC

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H089 HA40 KA17 QA02 QA08 TA03 TA05 TA06 UA05 2H092 GA48 GA50 NA25 NA29 PA01 PA05 PA06 5G435 AA11 AA13 BB12 EE42 EE47 GG42

Claims (4)

[Claims] 1. A display panel; two dust-proof glasses disposed on an incident surface and an output surface of the display panel; a case for storing the stacked display panel and two dust-proof glasses; And the two dustproof glasses, and between the display panel and the two dustproof glasses and the inner wall of the case, and are bonded and fixed to the display panel and the two dustproof glasses. And an adhesive for adhesively fixing the display panel and the two dust-proof glasses in the case. 2. The display device according to claim 1, wherein the adhesive is integrally filled in all the gaps in the case. 3. The flexible printed circuit according to claim 1, further comprising a flexible substrate connected to and fixed to the display panel, wherein the adhesive is also filled around the flexible substrate in the case. Display device. 4. A projection device using the display device according to claim 1. Description: