JP2004272722A - Touch panel device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent touch panel device that has a small peripheral space outside an operating area, in a five-wired transparent touch panel device having only a probe function for voltage detection on a movable transparent substrate and having a position detection function of two axes of ordinates and abscissas on a fixed transparent substrate. <P>SOLUTION: The touch panel device uses as an electrode material a conductive material of a resistivity of 1.0×10<SP>-4</SP>[Ω/cm] to 1.0×10<SP>-3</SP>[Ω/cm], and has the substantially same resistance of four electrodes disposed on the fixed transparent substrate. The electrodes have a resistance of 30 Ω to 500 Ω, a width of 2 mm or less and a straight line form. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a touch panel device that is arranged on a display device such as a CRT or a liquid crystal panel and is input with a finger, a pen, or the like, and particularly to a five-wire transparent touch panel device.
The five-wire transparent touch panel device includes a movable transparent substrate having a conductive surface and a fixed transparent substrate having a conductive surface, and the movable transparent substrate has a probe function of simply detecting a voltage. In addition, the opposed fixed-side transparent substrate has a position detecting function of two axes in the vertical and horizontal directions. That is, the movable-side transparent substrate has a basic structure of one sensing signal line, and the opposing fixed-side transparent substrate has four power supply lines, that is, a total of five connections.
[0002]
[Prior art]
The five-wire type transparent touch panel device has an advantage that the accuracy is not affected even if the resistance value of the conductive film on the movable side transparent substrate for sensing has a variation due to the position or the aging thereof, and the service life is long. is there.
However, on the other hand, the fixed transparent electrode substrate has a problem because electrodes are provided on two axes. Since the electrodes are formed on the four sides of the fixed transparent electrode substrate, an error occurs between the input position and the detection position, and the error increases as the distance from the center increases.
[0003]
In FIG. 3, an area surrounded by the electrodes 12, 23, 34, and 41 is a surface on which a touch input is performed. The area detected by switching the voltage on the vertical axis and the horizontal axis is a detection area 50 surrounded by a parabola. Therefore, in order to correct the bending distortions 112, 123, 134, and 141, the input position is calculated by using an approximate expression or by comparing with an actually measured value.
However, when the bending distortion areas 212, 223, 234, and 241 are wide, the accuracy is not high even if the calculation is performed using an approximate expression or compared with an actually measured value. In order to increase the accuracy, it is absolutely necessary to reduce the curved distortion areas 212, 223, 234, and 241 around the touch panel.
[0004]
As a countermeasure, there is a method of providing a large number of electrodes. (See, for example, Patent Document 1.) There is also a method of providing a leading wiring from the center point of each side, monitoring the voltage value thereof, and performing position correction. (For example, see Patent Document 2.)
In addition to the electrode pattern, there is another type in which a simple electrode is formed only when necessary by disposing a diode or the like without forming an electrode on four sides.
There is a method using a calculation formula to determine the resistance value of the electrode. (For example, see Patent Document 3)
[0005]
[Patent Document 1]
JP-A-61-182127 [Patent Document 2]
JP-A-10-83251 [Patent Document 3]
JP-A-2002-99389
[Problems to be solved by the invention]
However, in the above-described conventional method, since a large number of electrodes and diodes are provided in a space outside the operation area of the touch panel, the touch panel device becomes large. Therefore, it is an object of the present invention to provide a transparent touch panel that reduces the surrounding space outside the operation area.
[0007]
[Means for Solving the Problems]
In order to solve the above problem, the touch panel device according to claim 1 comprises a movable transparent substrate having a conductive surface and a fixed transparent substrate having a conductive surface. The electrode on each side provided on the substrate has a characteristic of 30Ω to 500Ω.
[0008]
A touch panel device according to a second aspect is characterized in that the width of the electrode is 2 mm or less.
[0009]
According to a third aspect of the present invention, in the touch panel device, the electrode has a linear shape.
[0010]
According to a fourth aspect of the present invention, the touch panel device is characterized in that a value obtained by dividing an area surrounded by the electrodes by an area of the fixed transparent substrate is larger than 0.8.
[0011]
A touch panel device according to a fifth aspect is characterized in that a hard coat and an anti-reflection coat are applied to a surface of the movable transparent substrate that does not face the fixed transparent substrate.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described specifically.
[0013]
Movable transparent substrate The movable transparent substrate has a total light transmittance of 50% or more, preferably 70% or more, and more preferably 90% or more. Further, a plastic substrate excellent in heat resistance, weather resistance, non-shrinkage, mechanical strength, chemical resistance and the like is preferable.
[0014]
Examples of the plastic substrate include polyester (PET), polyimide (PI), polyethersulfone (PES), polyetheretherketone (PEEK), polycarbonate (PC), polypropylene (PP), polyamide (PA), and polyacryl (PAC). ), A film of a norbornene-based thermoplastic transparent resin, or a laminate of these films. The thickness of the plastic substrate is usually about 0.05 to 5 mm, preferably about 0.1 to 0.3 mm.
The side of the movable transparent substrate that is not opposed to the fixed transparent substrate may be subjected to hard coat processing or anti-reflection processing, or may be laminated with a hard coat film, an anti-reflection processed film, or a polarizing film.
[0015]
Fixed-side transparent substrate As the fixed-side transparent substrate, a glass substrate such as soda glass, non-alkali glass, borosilicate glass, and quartz glass is preferable. The thickness of the glass substrate is about 0.05 to 5 mm, preferably about 0.1 to 3 mm. Further, a support may be laminated.
[0016]
Conductive film As the conductive film forming material of the movable transparent substrate and the fixed transparent substrate, an ITO (Indium Tin Oxide / indium tin oxide) film is often used, and a tin oxide film, copper, aluminum, nickel, and chromium are used. And so on. In addition, these alloys may be used, or different forming materials may be formed by overlapping. Before forming the transparent conductive film, an undercoat layer for improving transparency, adhesion, and the like may be provided. Depending on the type of the conductive film to be formed, a method such as a sputtering method, a vacuum deposition method, a PVD method such as an ion plating method, or a method such as a CVD method, a coating method, or a printing method is appropriately used. Selected. The resistance value of the conductive film on the movable transparent substrate is usually about 100Ω / □ to 500Ω / □. The resistance value of the conductive film of the fixed-side transparent substrate is usually about 500Ω / □ to 3000Ω / □.
[0017]
Patterning of conductive film Next, the conductive film of the fixed-side transparent substrate is patterned. As shown in FIG. 2, the outside of the electrode portions 12, 23, 34, and 41 becomes the wiring area 52 of the routing circuit, so that the conductive film is removed by etching. Of course, the conductive film may be cut by laser processing to keep the insulating property. The conductive film of the movable transparent substrate may be formed as needed.
[0018]
Electrode printing Next, electrode printing on the fixed-side transparent substrate is performed. The electrodes on the fixed transparent substrate are formed by screen printing, but the forming method is not particularly limited. In general, a silver paste, a copper paste, silver and carbon, or the like is used as an electrode material, but other materials may be selected as long as the material has a stable volume resistance and is stable. As for the selection of the conductive material, it is necessary to predict the resistance value of the electrode on each side in advance and select the volume resistance value of the conductive material.
[0019]
The resistance value of the electrode is preferably from 30 ohm to 500 ohm, more preferably from 60 ohm to 200 ohm, and most preferably from 80 ohm to 100 ohm, since the bending distortion is within 1%. As for the resistance value balance of each side, if the error exceeds 20%, the bending distortion exceeds 1.5%, so that it is desirable that the resistance values of each side become substantially the same. When the touch panel is rectangular, if the electrode width is changed to have substantially the same resistance value on the long side and the short side, control at the time of biaxial switching becomes easy.
[0020]
Specific resistance of the electrode ^{material, 1.0 × 10 - 4 [Ω} / cm] ~1.0 × 10 - 3 [Ω / cm] is preferred. 1.0 × 10 ^{- 4} off the low and proper resistance than [Ω / cm], 1.0 × 10 - 3 lacks high stability of the resistance value from [Ω / cm].
[0021]
Next, a circuit extending from the electrode on the fixed-side transparent substrate is printed. The drawing circuit is drawn from the place where the vertical and horizontal electrodes intersect. The electrodes and routing circuits are covered with insulating ink. Although an example is shown in FIG. 1, the routing circuits 61, 62, 63, and 64 are usually gathered at one place, and guided outside by a thermocompression-bonded flexible connector 60 or the like. In addition, a small dot spacer is provided on the fixed-side transparent substrate to avoid erroneous input when the movable-side transparent substrate is not in contact. One signal line is led to the outside from the movable transparent substrate, but may be directly from the movable transparent substrate or via the fixed transparent substrate. The periphery of the movable-side transparent substrate and the fixed-side transparent substrate are bonded together with a double-sided adhesive tape or the like.
The method of manufacturing the routing circuit may be a method other than printing.
[0022]
Hereinafter, the present invention will be described with examples.
Embodiment 1
On the movable side transparent substrate, a 300 Ω / □ ITO film was formed on a 188 μm-thick polyester film (PET) by sputtering. The fixed-side transparent substrate was formed by forming an ITO film of 2000 Ω / □ on soda glass having a size of 250 mm × 328 mm and a thickness of 2 mm by sputtering.
Next was produced an electrode by screen printing, the conductive material, carbon powder and silver powder, vinyl resin, phenol resin, silica filler and the like in addition, specific resistance 5.0 × 10 - was ^{4 [Ω} / cm].
The electrode shape of the fixed side transparent substrate after printing is
The short side is 236mm * 1.41mm,
The long side was 314 mm * 1.85 mm.
The value obtained by dividing the area surrounded by the electrodes by the fixed-side transparent substrate was 0.88, and the resistance values of the four electrodes were approximately 90Ω, and the variation was within 10%.
[0023]
After finishing the touch panel, the bending distortion was measured and found to be within 1%.
[0024]
【The invention's effect】
The present invention has the effect of reducing the space around the outside of the operation area in the five-wire transparent touch panel device.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of an electrode of a fixed transparent electrode substrate and a routing circuit of a five-wire transparent touch panel device according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of electrodes on a fixed transparent electrode substrate of the five-wire type transparent touch panel device according to one embodiment of the present invention.
FIG. 3 is an explanatory diagram of an electrode, a detection area, and a curved distortion area of a fixed transparent electrode substrate of a 5-wire transparent touch panel device.
[Explanation of symbols]
1, 2, 3, 4 Power supply terminals 12, 23, 34, 41 Electrode 50 Detection area 51 Conductive film part 52 Wiring area 60 of wiring circuit Flexible connectors 61, 62, 63, 64 Routing circuits 112, 123, 134, 141 Curve distortion 212, 223, 234, 241 Curve distortion area

Claims (5)

In a touch panel device comprising a movable transparent substrate having a conductive surface and a fixed transparent substrate having a conductive surface, and having a conductive surface facing each other, electrodes on each side provided on the fixed transparent substrate have a resistance of 30Ω to 500Ω. Characteristic touch panel device. The touch panel device according to claim 1, wherein the width of the electrode is 2 mm or less. The touch panel device according to claim 1, wherein the electrode has a linear shape. 4. The touch panel device according to claim 1, wherein a value obtained by dividing an area surrounded by the electrodes by an area of the fixed-side transparent substrate is greater than 0.8. 5. The touch panel device according to any one of claims 1 to 4, wherein a hard coat and an anti-reflection coat are applied to a surface of the movable side transparent substrate that does not face the fixed side transparent substrate.

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