JPH09244814A - Coordinate input device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide constitution which can securely apply a voltage without using any conductive adhesive and constitution which actualizes deflection prevention. SOLUTION: At least one substrate 11 to be touched is constituted by arranging two flexible insulating substrates 11 and 12 across a gap and forming transparent conductive films 13 and 14 on the opposite surfaces of the substrates 11 and 12. Further, a couple of parallel electrodes 15 and 16 are provided on two orthogonal sides on the two transparent conductive films 13 and 14 and the end parts of the electrodes 15 and 16 are led out at the peripheral parts of the substrates 11 and 12 so that they can be connected to an external circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device, and more particularly to a pressure-sensitive coordinate input device, that is, a structure of an input unit in a so-called touch panel.

[0002]

2. Description of the Related Art A conventional example will be described below with reference to FIG. FIG. 5 is a diagram showing a configuration of a conventional embodiment,
The pressure-sensitive coordinate input device shows the configuration of an input unit in a so-called touch panel (hereinafter, abbreviated as coordinate input device).

In FIG. 5, (1) is a sectional view showing the overall construction of the coordinate input device. (2) to (4) are diagrams showing the detailed configuration, (2) is a plan view of the upper substrate, (3) is a plan view of the lower substrate, and (4) is a plan view of the intermediate layer, for example. Is.

Reference numerals 51 to 66 are main components,
52 is a substrate, 53 and 54 are transparent conductive films, 55 is an insulating spacer, 56 and 57
Is an electrode. Further, 58 and 59 are insulating layers, and 60a and 60b are peripheral layers (structure is described later).

Further, 61 is a double-sided adhesive tape, 62a and 62b are routing electrodes, 63 is a conductive adhesive, 64 is an external connection electrode, 65 is a connection terminal, and 66 is a control system. The conventional coordinate input device is shown in FIG.
As shown in,
A solid film of the transparent conductive film 53 such as O or SnO _{2 is} provided by a sputtering method or an evaporation method, and a voltage applying electrode 56 (thickness, about 20 μm) of, for example, silver paste is provided on the peripheral portion of the transparent conductive film 53.
m), an insulating layer (two-layer structure) 58 (thickness, about 50 μm), and routing electrodes 62a, 62b (thickness, about 20 μm) are formed as a peripheral layer 60a.

The general procedure for forming the peripheral layer 60a is as follows. An electrode 56 and an insulating layer (lower layer portion) 58 are attached to a transparent conductive film 53 formed on a substrate 51. At this time, the electrode 56 and the routing electrode
The insulating layer 58 is not formed in advance at the place where it is connected to 62b.

The routing electrodes 62a and 62b are attached. The upper insulating layer 58 is attached on the lower insulating layer 59 including the leading electrode 62b. In addition, a transparent conductive film 54 similar to the transparent conductive film 53 is provided on the inner surface of the other substrate 52, and, for example, a silver paste electrode 57 (thickness: about 20 μm) and an insulating layer are provided on the periphery of the transparent conductive film 54. A peripheral layer 60b composed of 59 (thickness, about 50 μm) and the conductive adhesive 63 is formed.

The general procedure for forming the peripheral layer 60b is as follows. An electrode 57 and an insulating layer are formed on the transparent conductive film 54 formed on the substrate 52.
Add 59. At this time, the insulating layer 59 is not formed in advance on the portion of the electrode 57 where the conductive adhesive 63 is applied.

A conductive adhesive 63 is applied to a predetermined place. The transparent conductive film 53 and the transparent conductive film 54 are arranged so as to face each other with an insulating spacer 55 in between, and the two peripheral layers 60 are provided.
The a and 60b are overlapped and bonded with the double-sided adhesive tape 61 interposed.

Regarding the insulating spacer 55, its width, thickness, interval, etc. are set in consideration of a desired input load (force by pressing with a pen or a finger). In addition, in terms of operability, the equipment, such as the substrate
For 51, a transparent and flexible one (for example, polyester film) is selected. On the other hand, the lower side, for example, the substrate 52 does not necessarily need to be flexible and may be a rigid body.

In addition, the device is equipped with 2 units as described above.
Two routing electrodes 62a, 62b for voltage application are provided. In general,
The routing electrodes 62a and 62b are provided on, for example, the substrate 51 on the upper side of the two substrates 51 and 52, one routing electrode 62b is directly connected to the electrode 56, and the other routing electrode 62a is the lower side. For example, it is electrically connected to the electrode 57 on the substrate 52 via the conductive adhesive 63, and the two routing electrodes 62a and 62b are provided in the insulating layer 58 so as to be electrically insulated from each other.

Further, a four-terminal external connection electrode 64 is provided on a projecting end projecting in the peripheral portion of the substrate to connect the routing electrodes 62a and 62b to the outside, and a control system 66 side for controlling the input device is provided. A connection terminal (corresponding to a jack terminal of the connector) 65 provided on the above and the external connection electrode 64 are connected in a connector form.

Position detection by the coordinate input device having such a configuration is performed in the following procedure. (1) First, between the voltage applying electrodes 56 formed on both ends of the transparent conductive film 53 on the upper substrate 51 (two long sides of the transparent conductive film 53 in the figure), the connection terminal 65 and the external connection electrode A predetermined voltage from the control system 66, for example, +
By applying 5 V, horizontal equipotential lines are formed on the transparent conductive film 53.

(2) In this state, when the transparent conductive film 53 on the upper substrate 51 on the touch surface side is pressed (touched) by pressing a pen (not shown), the pressed portion is the transparent conductive film 54 on the lower side. Since it makes contact with the horizontal equipotential line at the contact point, it detects the potential on the transparent conductive film 54, and the read result is read by the electrode 57, conductive adhesive 63, routing electrode 62a, external connection electrode 64, and connection terminal 65. It outputs to the control system 66 via and detects the touched X coordinate position.

(3) Similarly, between the voltage applying electrodes 57 formed on both ends of the lower transparent conductive film 54 (two short sides of the transparent conductive film 54 in the figure), a vertical line perpendicular to the above is applied. In order to form a potential line, a predetermined voltage, for example + 5V, is applied from the control system 66 via the connection terminal 65, the external connection electrode 64, the routing electrode 62a and the conductive adhesive 63, and touched in the same manner as Y. The coordinate position is detected.

(4) The position of the two-dimensional coordinate is obtained from the intersection of the above (2) and (3). The same position detection can be performed by pressing the transparent conductive film 53 with a finger instead of the pen.

[0017]

In the coordinate input device of the conventional example, since the conductive adhesive is used to connect the voltage applying electrode and the routing electrode, when the conductive adhesive is not properly cured, Alternatively, if there is an external factor such as an external force or a usage environment, the electrical connection tends to be unstable. Furthermore, when forming the lead-out electrode, it is necessary to additionally form an insulating layer for ensuring electrical insulation between the voltage application electrode and the layer structure becomes complicated (first issue).
Challenges).

Also, in a high temperature and high humidity environment, the flexible substrate on the input surface side is bent, which may cause erroneous contact and
There is a problem (second problem) that the appearance is degraded. It is an object of the present invention to provide a configuration in which a voltage can be surely applied without using a conductive adhesive and a configuration in which flexure can be prevented.

[0019]

In order to achieve the above object, in the first invention, as shown in FIGS. 1 and 2, at least one substrate 11 to be touched has two flexible insulating substrates. 11 and 12 are arranged with a gap therebetween, and the respective substrates 11 and 12 are
Transparent conductive films 13 and 14 are formed on the surfaces facing each other,
A pair of parallel electrodes 15 and 16 is provided on each of the two sides of the two transparent conductive films 13 and 14 in a direction orthogonal to each other.
The ends of 5,16 are arranged so that they can be connected to an external circuit at the peripheral portions of the respective substrates 11,12.

Further, in the second invention, as shown in FIGS. 3 and 4, a tension spring for applying a tension to the substrate 31 between the flexible substrate 31 on the touch surface side and the housing 34. 33b
The board bending prevention mechanism 33 is formed.

[0021]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described with reference to FIGS. 1 is a diagram showing a configuration of a first embodiment of the present invention, FIG. 2 is a diagram showing a configuration of a second embodiment of the present invention, and FIG. 3 is a configuration of a third embodiment of the present invention. It is a figure and Drawing 4 is a figure showing the composition of the 4th example of the present invention. 1 and 2 correspond to the first problem, and FIGS.
Corresponds to the second problem.

It should be noted that, in FIGS. 1 to 4, the elements having the same reference numerals are the same. Also, those having the same names as those in FIG. 5 have the same functions as those shown in FIG. 5, and detailed description may be omitted. [First Embodiment] In FIG. 1, (1) is a plan view of an upper substrate, (2) is a cross-sectional view taken along the line AA 'of (1), (3) is a plan view of an intermediate layer,
(4) is its side view, (5) is a plan view of the lower substrate, (6) is (5)
It is a BB 'sectional view of.

In the figure, 11 is a substrate on the upper side, and 12 is a substrate on the lower side. In the device, a transparent and flexible material is selected for the upper substrate 11 from the viewpoint of operability. On the other hand, the lower substrate 12 does not necessarily need a flexible material and may be a rigid body.

Further, 13 and 14 are transparent conductive films, 15 and 16 are electrodes, and 17
Is an insulating spacer, 18 and 19 are insulating layers, 20 is a double-sided adhesive tape, 2
1 is a connection terminal. In this embodiment, the number of connection terminals 21 for electrical connection to the outside is four.

The details will be described below. Solid transparent conductive films 13 and 14 are formed on the opposing surfaces of the two flexible substrates 11 and 12, respectively, and a pair of parallel transparent conductive films 13 and 14 are formed on the transparent conductive films 13 and 14. Voltage application electrodes 15,1
6 are formed with silver paste or the like.

At this time, each electrode 15, 16 is formed in a rod shape with a thickness of about 20 μm on the long side and the short side of each transparent conductive film 13, 14 as shown in the figure. Each electrode 15,1
The ends of 6 are led out to the protruding ends that are projected to the peripheral portions of the respective substrates 11 and 12.

In addition, an insulating spacer 17 is formed on the surface of the lower side substrate 12 excluding the peripheral portion of the transparent conductive film 14, and a frame is formed around the transparent conductive films 13 and 14 on the respective substrates 11 and 12. -Shaped insulating layers 18 and 19 are respectively formed with a thickness of about 30 μm.

Then, the two substrates 1 are superposed so that the transparent conductive films 13 and 14 face each other with the insulating spacer 17 interposed therebetween.
The two substrates 11 and 12 are bonded together with the frame-shaped double-sided adhesive tape 20 interposed between the insulating layers 18 and 19 of the substrates 1 and 12.

Regarding the insulating spacer 17, the width, thickness, spacing, etc. are set in consideration of a desired input load (pressing force of a pen or a finger). Each of the electrodes 15 and 16 thus formed is connected in a plug-in form to the four voltage application connection terminals 21 that directly communicate with the control system 66 (not shown).

Therefore, the routing electrode as in the conventional example of FIG.
Since the formation of 62a and 62b and the conductive adhesive 63 are unnecessary,
It is possible to stabilize the electrical connection when a voltage is applied to the electrodes 15 and 16. [Second Embodiment] In FIG. 2, (1) is a plan view of the upper substrate, (2) is a sectional view taken along the line AA 'of (1), (3) is a plan view of the intermediate layer,
(4) is its side view, (5) is a plan view of the lower substrate, (6) is (5)
It is a BB 'sectional view of.

In the figure, reference numeral 22 is a wiring electrode. Regarding other points, those having the same reference numerals as those in FIG. 1 have the same names, and of course, their configurations and operations are also the same. In this embodiment, as in the first embodiment, the transparent conductive films 13 and 14 are formed on the opposing surfaces of the two flexible substrates 11 and 12, and the voltage is applied to the peripheral portions on the transparent conductive films 13 and 14. The electrodes 15 and 16 are formed in a rod shape with a thickness of about 20 μm using silver paste or the like.

Further, the two substrates 11 and 12 on which the insulating spacer 17 and the insulating layer 19 are formed are pasted and bonded by the double-sided adhesive tape 20. However, the point different from the first embodiment is that a wiring electrode 22 is provided at the end of the electrode 16 so that the connecting portion of the pair of electrodes 16 on the substrate 12 on the lower side is located at one place. The turning electrode 22 is directly connected to the connection terminal 21 on the control system 66 side in a plug-in form.

According to this structure, the number of connecting terminals 21 is three, and it is possible to reduce the number of connecting terminals 21 by one as compared with the first embodiment. At this time, it is necessary to form the leading electrode 22, but the electrode 16 and the leading electrode 22 can be simultaneously formed by removing the portion of the transparent conductive film 14 under the leading electrode 22 in advance. Therefore, it does not lead to an increase in the number of production steps and a complicated layer structure.

Also in this embodiment, since it is not necessary to use the conductive adhesive 63 shown in FIG.
Stable electrical connection when applying voltage to 15,16. [Third Embodiment] In FIG. 3, (1) is a partial side view of the coordinate input device, (2) is a plan view of (1) (No. 1), and (3) is a plan view of (1) (No. 2).

Further, 31 is an upper side substrate including the transparent conductive film 13 and the electrode 15 and the insulating layer 18 as described above, and 32 is a lower substrate including the transparent conductive film 14 and the electrode 16 and the insulating layer 19 as described above. It is the side substrate.

Reference numeral 33 is a substrate bending prevention mechanism, which comprises a connecting portion 33a and a tension spring 33b. And 34 is a housing. Regarding other points, those having the same reference numerals as those in FIGS. 1 and 2 have the same names, and, of course, their configurations and operations are also the same.

In the third embodiment, board bending prevention mechanisms 33 are provided at the four corners or two corners of the upper board 31, and the board bending prevention mechanisms 33 connect the four corners or two corners of the upper board 31 to the housing 34. The upper side substrate 31 can be prevented from being bent by pulling it to the side.

The board bending prevention mechanism 33 can be attached to the corners of the upper board 31 both in the four corners as shown in FIG. 3 (2) and in the two corners as shown in FIG. 3 (3). One end of the connecting portion 33a of the board deflection preventing mechanism 33 is fixed to the protruding portion by adhering or sandwiching the connecting portion 33a.
A configuration is conceivable in which the tension spring 33b provided at the other end is attached to the housing 34.

In this way, the upper substrate 31 is always provided with the housing 34.
Since the tensile force acts on the side, the bending of the substrate 31 can be prevented. In the upper substrate 31 to which the substrate bending prevention mechanism 33 is fixed, the transparent conductive films 13, 1 near the fixing portion are fixed.
If 4 is selectively removed beforehand, each transparent conductive film due to the pulling force from the substrate bending prevention mechanism 33 to the housing 34 side.
Since damage to 13 and 14 is prevented, it can greatly contribute to improving the reliability of the coordinate input device. [Fourth Embodiment] In FIG. 4, (1) is a partial side view of the coordinate input device, (2) is a plan view of (1) (1), (3) is a plan view of (1) (that 2).

Further, 41 is a fixed substrate, and the fixed substrate 41
Is equipped with a connection terminal 21 that communicates with the control system and is fixed to a casing 34 (not shown). Others, Figure 1
Those having the same reference numerals as those in FIG. 3 have the same names, and, of course, their configurations and operations are also the same.

In the fourth embodiment, the electrodes of the upper substrate 31 are
A substrate bending prevention mechanism 33 is provided between the fixed substrate 41 and the projecting portion from which the end portion of 15 is led out. Specifically, Figure 4, (2)
In this case, the connection part 33a of the board deflection prevention mechanism 33 is fixed by adhering or sandwiching it to the protruding end from which the end part of the electrode 15 of the upper side substrate 31 is drawn out, and the tension spring 33b with one end fixed to the connection part 33a. The other end of the connection terminal 21 is attached to the casing 34 side of the connection terminal 21, and the upper substrate 31 is always pulled toward the casing 34 in the same manner as in the third embodiment to prevent the upper substrate 31 from bending. There is.

In the case of FIG. 4 (3), a board bending prevention mechanism 33 is provided between the protruding end of the lower board 32, which is the end of the electrode 16, and the housing 34 side of the connection terminal 21. Therefore, it is possible to prevent the lower substrate 32 from bending.

In the fourth embodiment, the respective substrates 31, 3 are
Since it is not necessary to form a dedicated projecting end for attaching the board bending prevention mechanism 33 to the board 2, there is an advantage that the structure is simple. Also in this embodiment, similarly to the third embodiment, the transparent conductive films 13 and 14 near the fixed portions are selectively preliminarily selected in the upper substrate 31 and the lower substrate 32 to which the substrate bending prevention mechanism 33 is fixed. Therefore, if the transparent conductive film 1 is removed by the pulling force from the substrate bending prevention mechanism 33 to the fixed substrate 41 side,
Since 3,14 damage is prevented, it can greatly contribute to improving the reliability of the coordinate input device.

[0044]

As is apparent from the above description, according to the coordinate input device of the present invention, it is possible to connect the voltage application electrodes on the two substrates to the external connection terminals on the respective substrates. Therefore, unlike the conventional example, a conductive adhesive for electrically / mechanically connecting the electrode and the lead-out electrode is unnecessary, and the electrical connection is stable. Further, since it is not necessary to form the leading electrode, the layer structure formed on the substrate can be simplified.

Further, since the flexible substrate is provided with the bending prevention mechanism, the flexible substrate can be prevented from bending and a high-quality coordinate input device without erroneous contact can be formed.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a second embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a third exemplary embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a fourth exemplary embodiment of the present invention.

FIG. 5 is a diagram showing a configuration of a conventional example.

[Explanation of symbols]

11 substrate 12 substrate 13 transparent conductive film 14 transparent conductive film 15 electrode 16 electrode 17 insulating spacer 18 insulating layer 19 insulating layer 20 double-sided adhesive tape 21 connection terminal 22 routing electrode 31 upper side substrate 32 lower side substrate 33 substrate deflection prevention mechanism 33a Connection part 33b
Tension spring 34 Housing 41 Fixed board

Claims (2)

[Claims] 1. At least one of the substrates to be touched has two flexible insulating substrates arranged with a gap between them, and a transparent conductive film is formed on opposite surfaces of each substrate. A pair of parallel electrodes is provided on each of the two sides of the two transparent conductive films in the direction orthogonal to each other, and an end portion of each electrode is led out so that it can be connected to an external circuit in the peripheral portion of each substrate. A coordinate input device characterized by: 2. A substrate flexure preventing mechanism including a tension spring that applies tension to the substrate is provided between the one flexible substrate on the touch surface side and the housing portion. Item 1. The coordinate input device according to item 1.