JP2576068Y2 - Transparent touch panel - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent touch panel arranged on the front of a display device such as a liquid crystal display.

[0002]

2. Description of the Related Art In a liquid crystal display device, a transparent touch panel for detecting a data input position by pressing is used on a liquid crystal display.

[0003] The transparent touch panel is usually provided with a fixed substrate disposed on a display, a movable substrate facing away from the fixed substrate, and a transparent electrode formed on an opposing surface of the fixed substrate and the movable substrate. And dot-shaped spacers formed between the transparent electrodes. The size of the dot spacer is usually 0.5 to 2 mm in diameter and 50 μ in height.
m and are formed at a pitch of about 5 to 15 mm.

However, since the light from the display is scattered by a large number of spacers interposed between the transparent electrodes, the transparency of the touch panel is reduced and the display accuracy is impaired. Also, many dot-shaped spacers are usually screen-printed,
It is formed by a lithography method in which a photoresist is applied to the substrate and exposed and developed. However, these methods are complicated in operation.

Japanese Patent Publication No. 57-34543 discloses an input position detecting device in which the transparent electrodes of each substrate are composed of electrode groups orthogonal to each other and a pressure-sensitive conductive rubber sheet is interposed between the electrode groups. Have been.

However, since the pressure-sensitive conductive rubber sheet is composed of silicone rubber and dispersed metal particles, the transparency and display accuracy are impaired in this device as in the above case.

[0007] Therefore, the object of the present invention is high transparency,
An object of the present invention is to provide a transparent touch panel having excellent display accuracy and a simple structure.

[0008]

In order to achieve the above object, the inventors of the present invention have conducted intensive studies and have found that even if an electrically insulating material is used, a thin electrically insulating thin film can be formed between transparent electrodes. When it was formed, it was found that current was applied by pressing, and the present invention was completed. That is, the present invention includes a substrate disposed on the front surface of the display device, a movable substrate facing the substrate at a distance from the substrate, and transparent electrodes respectively formed on opposing surfaces of the substrate and the movable substrate. A transparent touch panel, wherein a thermoplastic resin, a thermosetting resin, an optical
It is selected from a polymerizable resin and silicon, and has a thickness of 0.
Provided is a transparent touch panel having an electrically insulating transparent thin film having a thickness of 005 to 1 μm and exhibiting an energizing effect when pressed.

In this touch panel, since a transparent thin film is interposed between the electrode parts instead of the dot-shaped spacer, the transparency is not impaired. In addition, since the transparent thin film is an electrical insulating film that exhibits a current-carrying effect by being pressed, the insulation of the electrode portion can be ensured in the non-pressed region, and conduction between the electrodes is performed in the pressed region. Further, the transparent thin film interposed between the transparent electrodes also functions as a spacer.

Further, since the touch panel is composed of two substrates on which transparent electrodes are formed and a transparent thin film,
The structure is simple.

[0011]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a schematic sectional view showing an example of the transparent touch panel of the present invention.

The transparent touch panel includes a fixed substrate 1 and a movable substrate 2 facing each other at a distance from each other, and is arranged on the front surface of a liquid crystal cell 6 as a liquid crystal display. In this example, the fixed substrate 1 is attached to the liquid crystal cell 6 with an adhesive 7 or an adhesive. The fixed substrate 1 and the movable substrate 2 are preferably formed of a transparent optically isotropic material in order to improve display quality. Examples of such a material include glass, an amorphous film, polyether sulfone, polycarbonate, polyarylate, and a polymer film such as uniaxially stretched polyethylene terephthalate. The term “film” is used to include a substantially flat sheet. The fixed substrate 1 and the movable substrate 2 may be configured by any combination of glass / glass, glass / film, film / glass, and film / film.

Transparent electrodes 3 and 4 are formed on opposing surfaces of the fixed substrate 1 and the movable substrate 2, respectively. The transparent electrode 3 of the fixed substrate 1 is composed of an electrode group extending parallel to the X-axis direction, and the transparent electrode 4 of the movable substrate 2 is composed of an electrode group extending parallel to the Y-axis direction orthogonal to the direction of the transparent electrode 3. It is composed of The ends of the electrode groups constituting the transparent electrodes 3 and 4 are as follows:
Each is connected to a resistor (not shown). A current is supplied to these resistors. Therefore, the data input position can be digitally detected by utilizing the fact that the contact between the transparent electrodes 3 and 4 due to the pressing and the degree of the voltage drop in the X-Y axis direction differ depending on the contact position.

Examples of the conductive material constituting the transparent electrodes 3 and 4 include noble metals such as gold-palladium, tin oxide, and the like.
Metal oxides such as indium oxide and indium tin oxide,
Copper iodide and the like can be used. Preferred transparent electrodes 3, 4
Can be formed using tin oxide, indium oxide, indium tin oxide, or the like. The transparent electrodes 3 and 4 can be formed by using a conventional thin film forming means such as a vacuum evaporation method, a sputtering method, an ion plating method, and a plasma CVD method.

Then, in order to enhance the transparency of the touch panel, the transparent electrodes 3 and 3 are interposed via the electrically insulating transparent thin film 5.
4 are stacked. The transparency of the electrically insulating transparent thin film 5 is, for example, 70 to 95% with a light having a wavelength of 550 nm.
It is about. In addition, the electrically insulating transparent thin film 5 exhibits an energizing effect when pressed. That is, the electrically insulating transparent thin film 5
When the movable substrate 2 is pressed, electrons move in the pressed area, and the transparent electrodes 3 and 4 are made conductive.

Examples of the material for forming the electrically insulating transparent thin film 5 include thermoplastic resins such as acrylic resin, polyvinyl chloride, polyester, polyamide, polycarbonate, and fluorine-containing resin; polyurethane, epoxy resin,
Thermosetting resins such as silicone resin and polyimide; photopolymerizable resins such as acrylic ultraviolet curing resin, epoxy ultraviolet curing resin, urethane ultraviolet curing resin, polyester ultraviolet curing resin, silicone ultraviolet curing resin Resin; inorganic materials such as silicon; Among these materials, silicone resin, photopolymerizable resin, silicon and the like are preferable. Further, preferred electrically insulating transparent thin films include polymer films that can be easily formed.

Although the thickness of the electrically insulating transparent thin film 5 is not particularly limited as long as it is within a range in which a current-carrying effect is exhibited by pressing depending on the kind of the thin film forming material, it is, for example, 0.005 to 1 μm.
m, preferably about 0.007 to 1 μm, and more preferably about 0.01 to 1 μm. When the electrically insulating transparent thin film 5 is formed of a polymer such as a photopolymerizable resin, the thickness is, for example, about 0.01 to 1 μm, preferably about 0.1 to 1 μm, and more preferably about 0.5 to 1 μm. It is.

The electrically insulative transparent thin film can be formed by various film forming means depending on the kind, for example, means such as coating such as spin coating, evaporation and sputtering. When forming an electrically insulating thin film by coating, the coating agent may contain an organic solvent as needed.

The electrically insulating transparent thin film may be interposed between the transparent electrodes, and may be separated from the transparent electrode by spacers interposed at both ends of the fixed substrate and the movable substrate. In order to enhance the performance, it is preferable that a transparent electrode and an electrically insulating thin film are laminated.

The data input position may be detected in an analog manner. In this case, the transparent electrodes 3 and 4 are fixed to the fixed substrate 1.
The resistor may be formed on both sides of the fixed substrate 1 in the X-axis direction, and the resistors may be formed on both sides of the movable substrate 2 in the Y-axis direction.

Further, a polarizing plate may be laminated on the surface of the fixed substrate opposite to the transparent electrode 3 with an adhesive or an adhesive, and may be provided on the front surface of the transparent touch panel, that is, on the surface of the movable substrate 2. , A polarizing plate may be laminated with an adhesive or the like. By laminating the polarizing plates, light from the liquid crystal cell travels in one direction, so that data can be clearly displayed. When a polarizing plate is laminated on at least the surface of the movable substrate,
The light transmitted through the transparent touch panel can be made to travel in one direction, and the display data has a clear floating feeling, and the display quality is significantly improved.

A protective layer made of a transparent hard coat layer may be formed on the surface of the movable substrate. The protective layer can be formed of a transparent and high-hardness material, for example, an organic thin film such as polycarbonate, or a transparent inorganic thin film such as silicon. Furthermore, on the surface of the movable substrate,
An anti-reflection layer may be formed.

The transparent touch panel of the present invention is used by laminating a fixed substrate on a liquid crystal cell or the like of a display device. The display device may be a liquid crystal display device or a cathode ray tube (CRT).

[0025]

[Effect of the Invention] The transparent touch panel of the present invention has high transparency, excellent display accuracy, and simple structure.

[0026]

EXPERIMENTAL EXAMPLE The present invention will be described in more detail below based on an experimental example.

Experimental Example 1 Indium tin oxide was deposited on glass having a thickness of about 1 mm to produce a fixed substrate having a transparent electrode having a thickness of 160 Å. In addition, indium tin oxide was vapor-deposited on a 125 μm-thick polyethylene terephthalate film to prepare a movable substrate having a transparent electrode with a thickness of 160 Å. The ends of the electrode group constituting each transparent electrode were each connected to a resistor.

An epoxy-based UV-curable resin [ThreeBond, ThreeBond 3064] is applied to the surface of the transparent electrode composed of an electrode group extending parallel to the X-axis direction of the fixed substrate by a spin coater. And a transparent electrode composed of an electrode group extending parallel to the Y-axis direction, and irradiating ultraviolet rays to cure the ultraviolet-curable resin, thereby producing a transparent touch panel. The thickness of the cured thin film of the ultraviolet curing resin was 0.5 μm.

Then, a transparent touch panel was arranged on the front surface of the liquid crystal cell of the liquid crystal display device, a voltage of 3 V was applied to the resistor, and the movable substrate was pressed.
The light transmittance of the transparent touch panel at 550 nm was 84%.

EXPERIMENTAL EXAMPLE 2 A transparent touch panel was produced in the same manner as in Experimental Example 1, except that a silicone resin was used in place of the UV-curable resin, and no UV irradiation was performed. The thickness of the silicone resin thin film was 0.7 μm. Then, in the same manner as in Experimental Example 1,
When a transparent touch panel was arranged on the front surface of the liquid crystal cell, a voltage of 3 V was applied to the resistor, and the movable substrate was pressed, the transparent electrode became conductive. In addition, 550nm of transparent touch panel
Was 85%.

Experimental Example 3 A film having a thickness of 0.04 μm was formed on the transparent electrode surface of the fixed substrate of Experimental Example 1.
Was formed, and the transparent electrodes of the movable substrate of Experimental Example 1 were laminated to produce a transparent touch panel. Then, in the same manner as in Experimental Example 1, a transparent touch panel was arranged on the front surface of the liquid crystal cell, a voltage of 3 V was applied to the resistor, and the movable substrate was pressed. The light transmittance of the transparent touch panel at 550 nm was 87%.

Experimental Example 4 Indium tin oxide was vapor-deposited on glass having a thickness of about 1 mm to prepare a fixed substrate having a transparent electrode having an electric resistance of 350 Ω / □. In addition, indium tin oxide was vapor-deposited on a 125 μm-thick polyethylene terephthalate film to obtain an electric resistance of 3 μm.
A movable substrate having a transparent electrode of 50Ω / □ was manufactured. Forming a silicon thin film having a thickness of 0.015 μm on the transparent electrode surface of the fixed substrate, laminating the transparent electrode of the movable substrate,
Analog transparent touch panel (15cm x 15cm)
Was prepared.

Then, in the same manner as in Experimental Example 1, a transparent touch panel was arranged on the front surface of the liquid crystal cell, and 5.5 V was applied to the resistor.
When the movable substrate was pressed and the transparent electrode was conductive, the resistance during conduction was 1.5 to 2 kΩ.

Experimental Example 5 The transparent electrode surface of the fixed substrate of Experimental Example 4 was
Is formed, and the transparent electrode of the movable substrate of Experimental Example 4 is laminated, and an analog type transparent touch panel (15 cm) is formed.
× 15 cm).

Then, in the same manner as in Experimental Example 4, a transparent touch panel was arranged on the front surface of the liquid crystal cell, and 5.5 V was applied to the resistor.
When the movable substrate was pressed and the transparent electrode was conductive, the resistance during conduction was 1.5 to 2 kΩ.

Experimental Example 6 A 0.06 μm thick film was formed on the transparent electrode surface of the fixed substrate of Experimental Example 4.
Is formed, and the transparent electrode of the movable substrate of Experimental Example 4 is laminated, and an analog type transparent touch panel (15 cm) is formed.
× 15 cm).

Then, in the same manner as in Experimental Example 4, a transparent touch panel was arranged on the front surface of the liquid crystal cell, and 5.5 V was applied to the resistor.
When the movable substrate was pressed and the transparent electrode was conductive, the resistance during conduction was 1.5 to 2 kΩ.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of the transparent touch panel of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Fixed substrate 2 ... Movable substrate 3, 4 ... Transparent electrode 5 ... Electrically insulating transparent thin film 6 ... Liquid crystal cell

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02F 1/1333 G06F 3/033 360

Claims (2)

(57) [Scope of request for utility model registration] 1. A transparent substrate comprising: a substrate disposed on a front surface of a display device; a movable substrate facing the substrate at a distance from the substrate; and transparent electrodes formed on respective surfaces of the substrate and the movable substrate. A touch panel, wherein heat is applied between the electrodes.
Plastic resin, thermosetting resin, photopolymerizable resin and silicon
And having a thickness of 0.005 to 1 μm
Both are transparent touch panels with an electrically insulative transparent thin film that exhibits an energizing effect when pressed. 2. The method according to claim 1, wherein the electrically insulating transparent thin film has a thickness of 0.01.
The transparent touch panel according to claim 1, wherein the thickness is from 1 to 1 m.