JPS63307627A - Transparent flat switch - Google Patents

Abstract

PURPOSE:To raise the mounting density, suppress the cost, and enhance the reliability by covering one of the electrodes with a transparent electroconductive film formed by application of transparent electroconductive coating, and by covering the other electrode with a transparent electroconductive film prepared by physical filming method, whereover another transparent electroconductive film formed by application of transparent electroconductive coating is further laid. CONSTITUTION:One of the electrodes 26 is so formed that a transparent electroconductive film is laid on an insulation sheet 21 by vacuum evaporation, sputtering, ion plating, whereover a transparent electroconductive coating is further applied, while the other electrode 31 so formed that a transparent electroconductive coating is applied on a transparent insulation sheet 27, wherein the later one 31 has spacer function, and these two electrode sheets are laid one over the other directly. This can eliminate insensitive zones to enable to obtain of coordinates data in follow up to the handwriting without breaks even though the mounting density is raised, that is further associated with low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a contact type transparent flat switch that utilizes the displacement of a transparent insulating sheet due to pressure.

[Conventional technology]

FIG. 8 is a cross-sectional view showing a conventional transparent flat switch shown, for example, on page 8 of "Touch Input System Development Trends and Application Development" published by the Japan Institute of Technology;
12 are plan views or sectional views showing each component.

In these 8th to 1θ figures, 1 is a transparent first insulating sheet that is easily displaced in the thickness direction due to stress, and 2 is a transparent conductive film provided on one side of the first insulating sheet 1. 3 is a first movable lead which is one signal extraction electrode of the movable electrode 2; 4 is a second movable lead which is the other signal extraction electrode of the movable electrode 2; 5 is the first insulating sheet 1; 8 and 11 show a movable electrode sheet composed of a movable electrode 2 and both movable leads 3.4.

In FIG. 12, reference numeral 6 denotes a transparent second insulating sheet corresponding to the first insulating sheet 1, and 7 denotes an individual constant voltage rod formed of a transparent conductive film and provided on one side of the second insulating sheet 6. ,
8 is a first fixed lead which is one signal extraction electrode of the fixed electrode 7, 9 is a second fixed lead which is the other signal extraction electrode of the fixed electrode 7, and lO is formed of an insulator and is placed on the fixed electrode 7. The provided insulating dot spacers 11 are the second insulating sheet 6, the fixed electrode 71, and both fixed leads 8, 9. A fixed electrode sheet composed of insulated dot spacers 10 is shown.

Next, the operation will be explained.

The transparent flat switch configured as shown in FIG.
When the first insulating sheet 1 is pressed as shown in FIG. 3, the first insulating sheet 1. Since the movable electrode 2 moves downward,
The movable electrode 2 and the fixed electrode 7 come into contact and the transparent flat switch becomes conductive. When the external stress applied to the first insulating sheet l decreases, the first insulating sheet l and the movable electrode 2 The displacement begins to return to its original state, and finally the movable electrode 2 and the fixed electrode 7 become non-conductive, and the first insulating sheet 1. The movable electrode 2 returns to its original state.

In this way, by applying or removing external stress to the first insulating sheet 1, both electrodes 2.7 are brought into a conductive state or a non-conductive state, and this state can be detected by an external circuit.

Furthermore, since both electrodes 2.7 are configured to have a uniform resistance distribution, for example, as shown in FIG. 14, a transparent flat switch is connected to a constant current source S, and both movable leads 3 and Inflow current ratio (X coordinate) and refixing lead 8
, 9 (X coordinate), and by converting these from analog to digital, the coordinates (X, Y) of the pressed position can be determined from the following equation.

1=i 1+12=i3+i4 Here, a: Dimension between both movable leads 3.4 b=Dimension between both fixed leads 8 and 9 I: Total current il: Inflow current from first movable lead 3 12: 1st Inflow current i3 from the second movable lead 4: the first fixed lead 8
Outflow current i4: Outflow current from the second fixed lead 9 Note that even if the transparent flat switch is connected to a constant voltage source, the coordinates (X, Y) of the pressed position can be found in the same way.

[Problem that the invention seeks to solve]

In the conventional transparent flat switch, an insulated dot spacer IO exists on a fixed electrode 7, and an insulated dot spacer 1
There was a problem in that the two electrodes 2.degree. 7 could not contact each other above and in the vicinity of 0, resulting in a dead zone N (FIG. 13). The insulation pitch of the transparent flat switch, that is, the pitch of the insulation dot spacers 10, is kept constant, and as the number of divisions between the insulation dot spacers 10 is increased and the mounting density is increased, the number of dead zones N also increases. There was a problem.

As a countermeasure against the increase in the dead band N, for example, if the shape of the insulated dot spacer 10 is made smaller, it can be improved a little, but new problems arise in terms of the adhesion of the insulated dot spacer 10 to the fixed electrode 7 and in manufacturing. In addition, even if the shape becomes smaller, the insulating dot spacer 10 remains on the fixed electrode 7, so this cannot be a fundamental countermeasure.

In addition, the materials used for both the movable and fixed electrodes are transparent conductive films or glass that have been coated with transparent conductive films using methods such as vacuum evaporation, sputtering, or ion plating. high,
As a result, this caused an increase in the cost of the transparent flat switch itself.

This invention was made in order to solve the above problems.One electrode is made of only a transparent conductive film made of transparent conductive paint, and the other electrode is formed using a physical film forming method such as vacuum evaporation, sputtering, or ion plating. With a simple electrode configuration in which a transparent conductive film made of transparent conductive paint is further provided on the transparent conductive film created by , packaging density can be easily increased. The purpose of the present invention is to obtain a highly reliable transparent flat switch that reduces costs by using only the - side.

[Means for solving problems]

In order to solve the above problems, the transparent flat switch of this invention has an electrode structure in which one electrode is coated with a transparent conductive film on a transparent insulating sheet by a method such as vacuum evaporation, sputtering, or ion plating. Furthermore, a transparent conductive paint was coated on top of this, and the other electrode was a transparent insulating sheet coated with a transparent conductive paint.The spacer function was also provided to the above electrode, and these two electrode sheets were directly laminated. It has a configuration.

[Effect]

In the transparent flat switch of this invention, when no external stress is applied, the electrodes coated with transparent conductive paint are in mechanical contact with each other, but electrically there is a large contact resistance between the electrodes. It has been abandoned. On the other hand, when external stress is applied, the contact resistance between the electrodes decreases, resulting in a conductive state. The value of external stress that causes this conduction state (
The operating force (acting force) changes mainly depending on the thickness of the transparent conductive paint, coating condition, conductivity, etc.

〔Example〕

An embodiment of the invention will be described with reference to the drawings.

In FIGS. 1 to 3, reference numeral 21 denotes a transparent first insulating sheet made of plastic, glass, etc., in the form of a film or a plate, which is easily displaced in the thickness direction due to stress; and 22, a transparent first insulating sheet. A planar first movable electrode formed of a transparent conductive film provided on one side of an insulating sheet 21 by a physical film forming method such as vacuum deposition, sputtering, or ion plating; 23 is a first movable electrode; A planar second movable electrode is formed by applying transparent conductive paint to the entire surface of the electrode 22, and 24 is a signal extraction electrode of one of the second movable electrodes 23 (first movable electrode 22). 1 movable lead,
25 is a second movable lead located opposite to the first movable lead and is the other signal extraction electrode; 26 is a transparent first insulating sheet 21; first movable electrode 22. Second movable electrode 2
3. First movable lead 24. FIG. 1 also shows a movable electrode sheet composed of a second movable lead 25.
In FIG. 5, reference numeral 27 corresponds to the first insulating sheet 21 and is a transparent second insulating sheet made of plastic, glass, etc. in the form of a film or plate, and 28 is a transparent second insulating sheet made of transparent conductive paint. A planar fixed electrode provided on one side of the second insulating sheet 27, 29 is the fixed electrode 2
a first fixed lead, 30, which is one of the signal extraction electrodes of 8;
31 is a second fixed lead located opposite to the first fixed lead and is the other signal extraction electrode of the fixed electrode 28; 31 is a transparent second insulating sheet 27. Fixed electrode 28. First fixed lead 29. A fixed electrode sheet composed of second fixed leads 30 is shown. As shown in FIG. 1, the transparent flat switch of this embodiment is constructed by laminating the above-mentioned movable electrode sheet 26 on a fixed electrode sheet 31, and when external stress is applied to the first insulating sheet l, the The resistance RC between the two electrodes 22.28 (Fig. 6), which was several 10KΩ or more in the state, began to decrease due to external stress as shown in Fig. 7, and finally decreased to 5.
It becomes a stable value of about Ω. Both stable electrodes 22
．． The conduction state can be defined by detecting the resistance value between 28. This value of 5 and Ω is the first movable electrode 22. Second movable electrode 23. Needless to say, it varies depending on the conductivity of each fixed electrode 28.

By the way, the resistance value between the electrodes 22, 28, especially the second movable electrode 23. This is contact resistance (occupies most of the resistance value between the electrodes) caused by the fixed electrode 28, and its value changes depending on external stress.

That is, the second movable electrode 23. By providing the fixed electrode 28, a pressure-sensitive characteristic is imparted between the electrodes, and the second movable electrode 23° having this pressure-sensitive characteristic.Since the fixed electrode 28 itself is both an electrode and a spacer, the pressure-sensitive characteristic appears uniformly everywhere.

Note that the first movable electrode 22 is made of gold, silver 1 liter carbon, nickel, tin, indium oxide, and tin oxide.

A transparent conductive film made of iodized steel, palladium, chromium, etc. by a physical film forming method, and the second movable type, pole 23. The fixed electrode 28 is a transparent conductive film coated with a transparent conductive paint in which the same material as described above is dispersed in a resin.

In the above embodiment, the movable electrode was made of two layers and the fixed electrode was made of one layer, but the movable electrode may be made of one layer and the fixed electrode made of two layers.Although the analog type was explained in the example, digital, digital/analog type It may be.

〔Effect of the invention〕

According to this invention, one electrode has a simple structure of a transparent conductive film made of a transparent conductive paint, and the other electrode has a simple structure of a transparent conductive film made of a transparent conductive paint on a transparent conductive film made by a physical film forming method, and these transparent conductive Since the membrane itself also functions as a spacer that separates the electrodes, it is possible to eliminate the dead zone N, and even if the packaging density is increased, coordinate data that follows handwriting can be obtained without interruption, and at a low cost. . Furthermore, since the transparent conductive paint itself has excellent scratch resistance, it has the effect of increasing reliability as a transparent flat switch.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a transparent flat switch according to an embodiment of the present invention, Fig. 2 is a plan view of the movable electrode sheet of Fig. 1, Fig. 3 is a cross-sectional view taken along the line ■-■ of Fig. 2, and Fig. 4 is a plan view of the fixed electrode sheet in FIG. 1, FIG. 5 is a sectional view taken along the line V-V in FIG. 4, and FIG. 6 is an equivalent circuit diagram of the transparent flat switch of the present invention.
Fig. 7 is a characteristic diagram showing the change in contact resistance against external stress, Fig. 8 is a sectional view of the conventional example, Fig. 9 is a plan view of the movable electrode sheet of Fig. 8, and Fig. 10 is a x of Fig. 9. -x sectional view, FIG. 11 is a plan view of the fixed electrode sheet in FIG. 8, FIG. 12 is a xi-xi sectional view in FIG. 11, and FIG. 13 shows the operating state of the transparent flat switch in FIG. 8. The sectional view and FIG. 14 are equivalent circuit diagrams in which a transparent flat switch is connected to a constant current source. 21: First insulating sheet, 22: Transparent conductive film, 23: Transparent conductive paint, 24.25: A pair of opposing movable leads, 26: Movable electrode sheet, 27: Second insulating sheet, 2
8: Transparent conductive paint, 29° 30: A pair of opposing fixed leads, 31: Fixed electrode sheet. Agent Daikun Masu tS <and 2 others) Procedural amendment (1 Showa year, month, day 1, case description Patent application No. 143782, 1982, 2)
Title of the invention: Transparent flat switch 3, Person making the amendment Representative Moriya Shiki 4, Agent 5, Subject of amendment - brief description of the drawing, Drawing column. 6. Contents of the amendment (1) Page 12, line 2 of the specification “Cross section in inches”
The text has been corrected to read "inch cross-sectional view." (2) The drawings, Figures 4, 9, and 11 will be corrected as shown in the attached sheet. Above Figure 4 Figure 9 --x 1, -x 2

Claims (1)

[Claims] In a transparent flat switch equipped with a movable electrode and a fixed electrode, one of the movable electrode and the fixed electrode is formed by vacuum deposition, sputtering, or ion plating on a transparent insulating sheet. The electrode consists of a transparent conductive film deposited using a physical film forming method such as the above, and a transparent conductive paint coated on top of the transparent conductive film, and the other electrode is composed of a transparent conductive paint coated on a transparent insulating sheet. A transparent flat switch is characterized in that both of these electrodes are laminated in a facing state.