Input Devices

Abstract

To provide an input device capable of suppressing variations for each product and further enlarging an output change in a high pressure region.SOLUTION: An input device comprises: an insulation substrate; a first conductive pattern and a second conductive pattern provided on the insulation substrate; and a conductive elastic member which includes a convex-shaped end, supported on the first conductive pattern and the second conductive pattern so as to move back and forth toward the side of the insulation substrate. In the input device, as a contact pressure of the convex-shaped end to the insulation substrate increases, a contact area of the convex-shaped end with the first conductive pattern and the second conductive pattern increases and electric resistance between the first conductive pattern and the second conductive pattern decreases. The insulation substrate includes a partition face separating the first conductive pattern and the second conductive pattern electrically independently. The partition face includes a tip abutment area to which a tip of the convex-shaped end is abutted and a periphery abutment area to which a periphery of the convex-shaped end is abutted. An island-shaped conductive pattern electrically independent of the first conductive pattern and the second conductive pattern is provided in the periphery abutment area.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an input device. [Background technology]

[0002] 2. Description of the Related Art Input devices including a resistance change detection type elastic member whose resistance value (electrical resistance value) changes when a pressing force is applied, and a pair of electrodes, are widely used as touch sensors in various electronic devices such as personal digital assistants.

[0003] As an input device equipped with such an elastic member, for example, Patent Document 1 discloses a pressure sensor having a contact member made of a resistor having conductive resistance and a pair of electrodes provided on a circuit board with which the contact member comes into contact. In this pressure sensor, when the contact member is pressed, the contact member comes into contact with the pair of electrodes and the contact area changes, thereby changing the resistance value between the pair of electrodes and promoting a decrease in the resistance value per unit pressing force in the later pressing stage. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-114178 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the pressure sensor of Patent Document 1, the electrodes are shaped so that the contact area between the contact member and the pair of electrodes increases as the contact member is pressed, which creates the problem that it is difficult to increase the contact area between the contact member and the pair of electrodes on the high stroke side.

[0006] In addition, it is difficult to design and manufacture the shape of the electrodes so that the contact area between the contact member and the pair of electrodes is even larger on the high stroke side, so even if the electrodes are designed to increase the current change on the high stroke side, there is a high possibility that the current change on the high stroke side will vary from electrode to electrode and will be unstable.

[0007] An object of one aspect of the present invention is to provide an input device that can suppress variation between products and can further increase output changes in the high-pressure region. [Means for solving the problem]

[0008] One aspect of the input device of the present invention comprises an insulating substrate, a first conductive pattern and a second conductive pattern provided on the insulating substrate, and a conductive elastic member having a convex end supported on the first conductive pattern and the second conductive pattern so as to be movable toward and away from the insulating substrate, wherein as the pressure of the convex end against the insulating substrate increases, the contact area between the convex end and the first conductive pattern and the contact area between the convex end and the second conductive pattern increase and the electrical resistance between the first conductive pattern and the second conductive pattern decreases, the insulating substrate has an isolation surface that separates the first conductive pattern and the second conductive pattern so as to be electrically isolated, the isolation surface having a tip abutment area with which the tip of the convex end abuts and a peripheral abutment area with which the periphery of the convex end abuts, and the peripheral abutment area comprises an island-shaped conductive pattern electrically independent from the first conductive pattern and the second conductive pattern. Effect of the Invention

[0009] One aspect of the input device according to the present invention can suppress variation between products and can further increase the output change in the high voltage region. [Brief description of the drawings]

[0010] [Figure 1] 1 is a perspective view showing a configuration of an input device according to a first embodiment of the present invention. [Diagram 2] 2 is a plan view showing a partial configuration of the input device as seen from the AA direction in FIG. 1. FIG. [Diagram 3] FIG. 2 is a cross-sectional view of FIG. [Figure 4] FIG. 2 is a cross-sectional view taken along line II-II of FIG. [Diagram 5] 13 is an explanatory diagram showing a state in which a conductive elastic member is in contact with an upper surface of an island-shaped conductive pattern. FIG. [Figure 6] 11 is an explanatory diagram showing a state in which a conductive elastic member is pressed against and deformed on an upper surface of an island-shaped conductive pattern; FIG. [Figure 7] FIG. 4 is an explanatory diagram showing an example of a relationship between a stroke and a resistance value. [Figure 8] FIG. 4 is an explanatory diagram showing an example of a relationship between a stroke and a current value. [Figure 9] FIG. 13 is a plan view showing an example of another configuration of the island-shaped conductive pattern. [Figure 10] 11 is a plan view showing an example of another configuration of the first conductive pattern and the second conductive pattern. FIG. [Figure 11] 11 is a plan view showing an example of another configuration of the first conductive pattern and the second conductive pattern. FIG. [Figure 12] 11 is a plan view showing an example of another configuration of the first conductive pattern and the second conductive pattern. FIG. [Figure 13] FIG. 11 is a plan view showing an example of a configuration of an input device according to a second embodiment of the present invention. [Figure 14] FIG. 4 is an explanatory diagram showing an example of a relationship between a stroke and a current value. [Figure 15] FIG. 13 is a plan view showing an example of another configuration of the island-shaped conductive pattern. [Figure 16] FIG. 4 is an explanatory diagram showing an example of a relationship between a stroke and a current value. [Figure 17] 4 shows the measurement results of the current values ​​of the input devices in Example 1 and Comparative Example 1. [Figure 18] 13 shows the measurement results of the current values ​​of the input devices of Example 2 and Comparative Example 2. [Figure 19] 13 shows the measurement results of the current values ​​of the input devices of Example 3 and Comparative Example 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments of the present invention will be described in detail. In order to facilitate understanding of the description, the same components in each drawing are given the same reference numerals, and duplicated descriptions will be omitted. In addition, the scale of each member in the drawings may differ from the actual scale. In this specification, "~" indicating a numerical range means that the numerical values ​​before and after it are included as the lower and upper limits, unless otherwise specified.

[0012] [First embodiment] An input device according to a first embodiment of the present invention will be described. FIG. 1 is a perspective view showing the configuration of the input device according to the first embodiment of the present invention, FIG. 2 is a view seen from the AA direction of FIG. 1 and a plan view showing a configuration of a part of the input device, FIG. 3 is a cross-sectional view taken along line II in FIG. 2, and FIG. 4 is a cross-sectional view taken along line II-II in FIG. 2. As shown in FIG. 1 and FIG. 2, the input device 1A includes an insulating substrate 10, a first conductive pattern 20A and a second conductive pattern 20B, a conductive elastic member 30, and island-shaped conductive patterns 40A and 40B, and increases or decreases the electrical resistance between the first conductive pattern 20A and the second conductive pattern 20B depending on the degree of pressing of the conductive elastic member 30 against the first conductive pattern 20A and the second conductive pattern 20B.

[0013] In this specification, a three-dimensional orthogonal coordinate system in three axes (X-axis, Y-axis, and Z-axis) is used, with the direction perpendicular to the arrangement direction of the island-shaped conductive patterns 40A and 40B being the X-axis direction, the arrangement direction of the island-shaped conductive patterns 40A and 40B being the Y-axis direction, and the height direction of the input device being the Z-axis direction. The conductive elastic member 30 side of the input device 1A is the +Z-axis direction, and the insulating substrate 10 side is the -Z-axis direction. In the following description, for convenience of explanation, the +Z-axis direction side will be referred to as the upper side or top, and the -Z-axis direction side will be referred to as the lower side or bottom, but this does not represent a universal up-down relationship.

[0014] The insulating substrate 10 is a substrate for mounting the first conductive pattern 20A and the second conductive pattern 20B. The insulating substrate 10 only needs to have insulating properties, and can be made of synthetic resins such as polyamide (PA), polyimide (PI), polybutylene terephthalate (PET), polyethylene naphthalate (PEN), polyetherimide (PEI), polyethersulfone (PES), polystyrene (PS), polymethyl methacrylate (PMMA), polyethylene nitrile, polyether ether ketone (PEEk), polyphenylene sulfide (PPS), phenol, epoxy (containing glass filler), and polycarbonate (PC). These may be used alone or in combination of two or more. Among these, it is preferable to use polyimide, polyethylene terephthalate, or the like from the viewpoint of heat resistance, etc.

[0015] As shown in FIGS. 2 and 3, the insulating substrate 10 has a separating surface 11 on a main surface 10a of the insulating substrate 10, which separates the first conductive pattern 20A and the second conductive pattern 20B, in a plan view.

[0016] The isolation plane 11 separates the first conductive pattern 20A and the second conductive pattern 20B so as to be electrically isolated from each other.

[0017] As shown in Figures 2 and 4, the isolation surface 11 has a tip abutment area 111 with which the tip of the convex end 31 of the conductive elastic member 30 abuts, and a peripheral abutment area 112 with which the periphery of the convex end 31 abuts.

[0018] The first conductive pattern 20A and the second conductive pattern 20B are provided on the main surface 10a of the insulating substrate 10, as shown in FIGS.

[0019] The first conductive pattern 20A and the second conductive pattern 20B may be formed in a semicircular shape in a plan view as shown in Figures 1 and 2. The first conductive pattern 20A and the second conductive pattern 20B may be formed substantially symmetrically with respect to the separating surface 11.

[0020] The first conductive pattern 20A and the second conductive pattern 20B may be formed in a shape other than a semicircular shape in a plan view. Furthermore, the first conductive pattern 20A and the second conductive pattern 20B do not have to be formed symmetrically with respect to the separating surface 11.

[0021] Examples of materials for forming the first conductive pattern 20A and the second conductive pattern 20B include various metals such as gold (Au), silver (Ag), copper (Cu), nickel (Ni), iron (Fe), aluminum (Al), tin (Sn), lead (Pb), chromium (Cr) and cobalt (Co); alloys thereof; and carbon-based materials such as carbon black, graphite, carbon nanotubes, carbon fibers, and fullerene. The materials for forming the first conductive pattern 20A and the second conductive pattern 20B may be one type alone or two or more types in combination. Among these, it is preferable to use Ag or Cu as the material for forming the first conductive pattern 20A and the second conductive pattern 20B in terms of connection stability, reduction in manufacturing cost, ease of production, and the like. The first conductive pattern 20A and the second conductive pattern 20B may be formed of one metal layer, or may be configured by laminating a plurality of metal layers.

[0022] The first conductive pattern 20A and the second conductive pattern 20B may be a composite film in which the material forming the first conductive pattern 20A and the second conductive pattern 20B is dispersed in a binder as a conductive member. This makes it easier for the first conductive pattern 20A and the second conductive pattern 20B to deform in response to the pressure of the convex end portion 31 of the conductive elastic member 30.

[0023] As the binder, an elastomer or a synthetic resin can be used. As the elastomer, for example, natural rubber, silicone rubber, chloroprene rubber, isoprene rubber, butyl rubber, acrylic rubber, nitrile rubber, urethane rubber, polyisobutylene rubber, butadiene rubber, styrene-butadiene rubber, ethylene-propylene rubber, chlorosulfonated polyethylene rubber, epichlorohydrin rubber, polyester rubber, fluororubber, and modified products thereof can be used. As the synthetic resin, a flexible epoxy resin can be used. These may be used alone or in combination of two or more.

[0024] Furthermore, the first conductive pattern 20A and the second conductive pattern 20B may use an electronically conductive conductive polymer as a material for forming the first conductive pattern 20A and the second conductive pattern 20B. Examples of the electronically conductive conductive polymer include poly3,4-ethylenedioxythiophene (PEDOT), PEDOT / PSS obtained by doping PEDOT with polystyrene sulfonic acid (poly4-styrene sulfonate; PSS), polyacetylene, polyaniline, polyaniline sulfonic acid, polythiophene, polyphenylene vinylene, and polypyrrole. These may be used alone or in combination of two or more. Among them, it is preferable to use PEDOT, PEDOT / PSS, or polyaniline sulfonic acid in terms of lowering the contact impedance with a living body. It is more preferable to use PEDOT / PSS in terms of lowering the contact impedance with a living body and having high conductivity.

[0025] When the first conductive pattern 20A and the second conductive pattern 20B are made of a metal, an alloy, a carbon-based material, or a composite film, the thickness of the first conductive pattern 20A and the second conductive pattern 20B is preferably 1 μm to 50 μm, more preferably 5 μm to 30 μm, and even more preferably 10 μm to 20 μm. If the thickness of the first conductive pattern 20A and the second conductive pattern 20B is within the range of 1 μm to 50 μm, sufficient conductivity can be ensured. Furthermore, the thickness of the first conductive pattern 20A and the second conductive pattern 20B is determined according to the magnitude of the current to be passed, and may be 50 μm or more.

[0026] When the first conductive pattern 20A and the second conductive pattern 20B are made of a conductive polymer, the thickness of the first conductive pattern 20A and the second conductive pattern 20B is preferably 10 μm to 100 μm, more preferably 20 μm to 75 μm, and even more preferably 25 μm to 50 μm. If the thickness of the first conductive pattern 20A and the second conductive pattern 20B is within the range of 10 μm to 100 μm, the first conductive pattern 20A and the second conductive pattern 20B can have sufficient strength and conductivity.

[0027] The conductive elastic member 30 is provided above the first conductive pattern 20A and the second conductive pattern 20B, as shown in Fig. 1. The conductive elastic member 30 is supported within the main body of the input device 1A by a support mechanism (not shown) or the like so as to be movable toward and away from the insulating substrate 10, as shown in Fig. 2 and Fig. 3.

[0028] The conductive elastic member 30 is formed in a cylindrical shape as shown in Fig. 1, and has a convex end portion 31 at its tip, which is a surface that can come into contact with the first conductive pattern 20A and the second conductive pattern 20B, as shown in Fig. 2 and Fig. 3. The convex end portion 31 is formed in a rounded curved shape, and may be formed in a dome shape.

[0029] The convex end 31 is a dome-shaped tip portion of the conductive elastic member 30, and includes the tip that contacts the first conductive pattern 20A and the second conductive pattern 20B, and the surrounding area of ​​the tip that may come into contact with the first conductive pattern 20A and the second conductive pattern 20B.

[0030] The conductive elastic member 30 is formed by including a conductive material in an elastically deformable member, thereby electrically connecting the first conductive pattern 20A and the second conductive pattern 20B.

[0031] The conductive material may be the above-mentioned metal, alloy, or carbon-based material, and the elastically deformable member may be made of an elastomer such as silicone rubber, chloroprene rubber, isoprene rubber, butyl rubber, fluororubber, or urethane rubber.

[0032] When the conductive elastic member 30 is made of an elastomer, the rubber hardness of the conductive elastic member 30 is preferably within a range of 40 to 70, and more preferably within a range of 50 to 60. If the rubber hardness is within a range of 40 to 70, the conductive elastic member 30 can have sufficient strength. The rubber hardness is a value specified by the Japanese Industrial Standard JIS K6301.

[0033] As shown in FIGS. 1 and 2, the island-shaped conductive patterns 40A and 40B are provided in the peripheral abutment area 112 of the isolation surface 11 so as to be electrically independent from the first conductive pattern 20A and the second conductive pattern 20B.

[0034] As shown in FIG. 2, the island-shaped conductive patterns 40A and 40B are disposed between the opposing first and second conductive patterns 20A and 20B.

[0035] The island-shaped conductive patterns 40A and 40B can be made of the above-mentioned metals, alloys, carbon-based materials, composite films, and conductive polymers.

[0036] The island-shaped conductive patterns 40A and 40B may have the same thickness, as shown in FIG.

[0037] The thickness of the island-shaped conductive patterns 40A and 40B can be appropriately set according to the thickness of the first conductive pattern 20A and the second conductive pattern 20B, and may be substantially the same as the thickness of the first conductive pattern 20A and the second conductive pattern 20B, or may be thicker than the first conductive pattern 20A and the second conductive pattern 20B. If the island-shaped conductive patterns 40A and 40B have a thickness equal to or greater than the thickness of the first conductive pattern 20A and the second conductive pattern 20B, the island-shaped conductive patterns 40A and 40B can easily ensure conduction between the first conductive pattern 20A and the second conductive pattern 20B.

[0038] The shortest distance L1 between the island-shaped conductive pattern 40A and the island-shaped conductive pattern 40B can be set appropriately depending on the material, shape, size, etc. of the first conductive pattern 20A, the second conductive pattern 20B, the conductive elastic member 30, the island-shaped conductive pattern 40A and the island-shaped conductive pattern 40A40B, and is preferably 50 μm to 5 mm, and more preferably 100 μm to 3 mm.

[0039] In the input device 1A, as shown in Fig. 4, the conductive elastic member 30 is disposed on the upper surfaces of the island-shaped conductive patterns 40A and 40B in a non-contact state. When the conductive elastic member 30 is pressed from above and lowered, the conductive elastic member 30 comes into contact with the upper surfaces of the island-shaped conductive patterns 40A and 40B, and the conductive elastic member 30 comes into contact with parts of the island-shaped conductive patterns 40A and 40B, and a current starts to flow between the first conductive pattern 20A and the second conductive pattern 20B. Then, as shown in Fig. 6, when the conductive elastic member 30 is further pressed and lowered, and the pressure contact force of the convex end 31 against the insulating substrate 10 increases, the conductive elastic member 30 is bent and deformed, and the contact area between the convex end 31 and the first conductive pattern 20A and the contact area between the convex end 31 and the second conductive pattern 20B increase, and the electrical resistance between the first conductive pattern 20A and the second conductive pattern 20B decreases. As the pressing force of the convex end 31 against the insulating substrate 10 increases, the conductive elastic member 30 is further flexed and deformed, so that the first conductive pattern 20A and the second conductive pattern 20B are electrically connected through the island-shaped conductive patterns 40A and 40B. As a result, as shown in Fig. 7, the pressing force of the convex end 31 against the insulating substrate 10 increases, and the stroke of the conductive elastic member 30 becomes larger, so that the resistance value between the first conductive pattern 20A and the second conductive pattern 20B is further reduced compared to the case where the island-shaped conductive patterns 40A and 40B are not present (broken line in Fig. 7). As a result, the conductivity between the first conductive pattern 20A and the second conductive pattern 20B is increased, and as shown in Fig. 8, the value of the current flowing between the first conductive pattern 20A and the second conductive pattern 20B is increased compared to the case where the island-shaped conductive patterns 40A and 40B are not present (broken line in Fig. 8).

[0040] The input device 1A has a separation surface 11 on the main surface 10a of the insulating substrate 10 that separates the first conductive pattern 20A and the second conductive pattern 20B, and has island-shaped conductive patterns 40A and 40B in a peripheral contact area 112 of the separation surface 11. The peripheral contact area 112 is located in a range where the contact area of ​​the convex end 31 with the first conductive pattern 20A and the second conductive pattern 20B is large and the stroke of the conductive elastic member 30 is large. In the input device 1A, the island-shaped conductive patterns 40A and 40B are disposed in the peripheral contact area 112 between the first conductive pattern 20A and the second conductive pattern 20B, so that even in a range where the conductive elastic member 30 descends and the stroke is large, the island-shaped conductive patterns 40A and 40B bridge the conduction between the first conductive pattern 20A and the second conductive pattern 20B, and the amount of current flowing between the first conductive pattern 20A and the second conductive pattern 20B can be increased. Therefore, the current change on the high stroke side can be increased. Therefore, the input device 1A can suppress variations between products and can further increase the output change in the high voltage region.

[0041] The high stroke is a range in which the stroke is equal to or greater than a predetermined value. The predetermined value is not limited to a specific stroke, and is set appropriately according to the size, material, design, and the like of each member constituting the input device 1A, such as the first conductive pattern 20A, the second conductive pattern 20B, and the conductive elastic member 30. For example, the high stroke may be the stroke at the time when the conductive elastic member 30 presses the first conductive pattern 20A and the second conductive pattern 20B, or when the first conductive pattern 20A and the second conductive pattern 20B start to be deformed by the conductive elastic member 30.

[0042] Furthermore, the input device 1A can increase the amount of change in current in a range where the stroke of the conductive elastic member 30 is large, without changing the design of the first conductive pattern 20A and the second conductive pattern 20B or the material of the conductive rubber that constitutes the conductive elastic member 30.

[0043] Furthermore, in the input device 1A, the island-shaped conductive patterns 40A and 40B can be formed using a material having a different resistivity from that of the first conductive pattern 20A and the second conductive pattern 20B. As a result, the island-shaped conductive patterns 40A and 40B have a different conductivity from that of the first conductive pattern 20A and the second conductive pattern 20B, and therefore the input device 1A can easily increase the amount of change in current by increasing the amount of current flowing between the first conductive pattern 20A and the second conductive pattern 20B on the high stroke side where the stroke of the conductive elastic member 30 is large.

[0044] In addition, when the input device does not have the island-shaped conductive patterns 40A and 40B, the selection of the material constituting the conduction is limited to one type of the first conductive pattern 20A and the second conductive pattern 20B, and is determined only by the resistance value of the material constituting the first conductive pattern 20A and the second conductive pattern 20B. In addition, when materials with different resistivities are used for the first conductive pattern 20A and the second conductive pattern 20B, it is difficult to form the first conductive pattern 20A and the second conductive pattern 20B so that their heights are the same, and the amount of change in load relative to the stroke size is likely to differ. The input device 1A can change the resistance value of the material, and can make the heights of the first conductive pattern 20A and the second conductive pattern 20B approximately the same, and can easily adjust the amount of change in load relative to the stroke size to be approximately the same.

[0045] In the input device 1A, the island-shaped conductive patterns 40A and 40B can be formed in an elongated shape extending in a direction from the tip contact area toward the peripheral contact area. This allows the input device 1A to increase the amount of change in current in a range where the stroke of the conductive elastic member 30 is large, and therefore makes it easy to increase the output change in a wide range.

[0046] In this embodiment, either one of the island-shaped conductive patterns 40A and 40B may be used.

[0047] In this embodiment, as shown in FIG. 9, the island-shaped conductive patterns 40A and 40B may be rectangular in plan view.

[0048] In this embodiment, the first conductive pattern 20A and the second conductive pattern 20B may be formed in a comb shape in plan view as shown in Fig. 10, or may be formed in a diamond shape as shown in Fig. 11. In plan view, the first conductive pattern 20A and the second conductive pattern 20B may be formed in a shape in which the opposing outer edges of the pair of the first conductive pattern 20A and the second conductive pattern 20B have a mountain shape having an apex that first comes into contact with a contact portion, a valley shape generated at both ends of the mountain shape, and an oblique shape that rises obliquely from the valley shape are continuous, as shown in Fig. 12.

[0049] [Second embodiment] An input device according to a second embodiment of the present invention will be described. Fig. 13 is a plan view showing an example of the configuration of the input device according to this embodiment. As shown in Fig. 13, the input device 1B includes a plurality of island-shaped conductive patterns 40A and 40B of the input device 1A according to the first embodiment, each of which is provided at a predetermined interval. In this embodiment, each of the island-shaped conductive patterns 40A and 40B is formed in a rectangular shape in a plan view, and two of each are provided.

[0050] In the input device 1B, similar to the input device 1A, the island-shaped conductive patterns 40A and 40B are disposed in the peripheral contact area 112 between the first conductive pattern 20A and the second conductive pattern 20B. Even in the range where the conductive elastic member 30 descends and the stroke is large, the island-shaped conductive patterns 40A and 40B bridge the conduction between the first conductive pattern 20A and the second conductive pattern 20B, and the amount of current flowing between the first conductive pattern 20A and the second conductive pattern 20B can be increased. Therefore, for example, as shown in FIG. 14, the current change on the high stroke side can be made larger. Therefore, similar to the input device 1A, the input device 1B can suppress the variation between products and further increase the output change in the high voltage region.

[0051] In addition, the island-shaped conductive patterns 40A and 40B of the input device 1B can be formed using materials with different resistivities. For example, the island-shaped conductive patterns 40A and 40B located on the inside of the two island-shaped conductive patterns 40A and 40B can be formed using a carbon material, and the island-shaped conductive patterns 40A and 40B located on the outside can be formed using Ag. As a result, the island-shaped conductive patterns 40A and 40B located on the inside and the island-shaped conductive patterns 40A and 40B located on the outside have different conductivities, so that the input device 1B can be easily adjusted so that the amount of current flowing between the first conductive pattern 20A and the second conductive pattern 20B becomes larger on the high stroke side where the stroke of the conductive elastic member 30 is large, and the gradient of the change in current becomes larger.

[0052] In this embodiment, the number of each of the island-shaped conductive patterns 40A and 40B may be three or more, for example, four as shown in FIG. 15. The island-shaped conductive patterns 40A and 40B may not have the same size. This allows the current value to be increased stepwise, for example, as shown in FIG. 16. Therefore, the input device 1B can increase the output change in the high voltage region stepwise. EXAMPLES

[0053] The embodiments will be described in more detail below with reference to examples and comparative examples, but the embodiments are not limited to these examples and comparative examples.

[0054] <Example 1> [Creating an input device] A pair of semicircular conductive patterns (PEDOT / PSS, "Clevios", manufactured by Heraeus) was formed on an insulating substrate with a height of 1 μm or less in a plan view. The distance between the pair of conductive patterns was 0.2 mm. Then, Ag ink (manufactured by Toyobo Co., Ltd.) was applied to the peripheral abutment area of ​​the separating surface between the pair of conductive patterns, and a pair of island-shaped conductive patterns (Ag) was formed with a height of 50 μm so as to face the peripheral abutment area. A conductive elastic member (manufactured by Asahi Rubber Co., Ltd.) was placed on the pair of conductive patterns to produce the input device shown in Figure 3.

[0055] [Measurement of current value when pressing] While pressing the conductive elastic member, the value of the current flowing between the pair of conductive patterns was measured. The measurement results are shown in Fig. 17. The measurement results of an input device that does not have a pair of island-shaped conductive patterns are shown as Comparative Example 1.

[0056] As shown in FIG. 17, in Example 1 and Comparative Example 1, the detection positions of the initial resistance values ​​were equivalent, but in Example 1, the amount of current became larger as the stroke was increased than in Comparative Example 1.

[0057] Furthermore, when the current values ​​of multiple input devices manufactured in the same manner as in Example 1 were measured, there was almost no error in the current values ​​measured by each input device, and the amount of current on the high stroke side was approximately stable and large.

[0058] Therefore, in both input devices of Example 1, a pair of island-shaped conductive patterns is provided so as to face the peripheral abutment area of ​​the separating surface between a pair of conductive patterns on the insulating substrate, thereby increasing the amount of current flowing between the first conductive pattern and the second conductive pattern on the high stroke side, and increasing the current change. Therefore, it can be said that the input device of Example 1 can suppress the variation between products and increase the output change in the high voltage region.

[0059] <Example 2> The same procedure as in Example 1 was followed except that the shape of the island-shaped conductive pattern in plan view was changed from a substantially triangular shape to a rectangular shape, and two island-shaped conductive patterns each formed in a rectangular shape were provided. In plan view of the conductive elastic member, the island-shaped conductive pattern located on the inside from the conductive elastic member toward the side surface of the insulating substrate was formed of carbon, and the island-shaped conductive pattern located on the outside was formed of silver. The measurement results of measuring the current flowing between a pair of conductive patterns while pressing the conductive elastic member are shown in FIG. 18. The measurement results of an input device in which a pair of island-shaped conductive patterns is not arranged are shown as Comparative Example 2.

[0060] 18, the detection positions of the initial resistance values ​​were the same in Example 2 and Comparative Example 2, but Example 2 was able to rapidly increase the amount of current as the stroke was increased compared to Comparative Example 2. This is believed to be because the current flowed more easily between the pair of rectangular island-shaped conductive patterns via the square island-shaped conductive patterns. In addition, the material of the island-shaped conductive patterns located on the outside was made of Ag, which has higher conductivity than carbon used as the material of the island-shaped conductive patterns located on the inside, and therefore it can be said that it is easier to increase the amount of current on the high stroke side.

[0061] Furthermore, when the current values ​​of multiple input devices manufactured in the same manner as in Example 2 were measured, there was almost no error in the current values ​​measured by each input device, as in Example 1, and the amount of current on the high stroke side was approximately stable and large.

[0062] Therefore, in both input devices of Example 2, a pair of island-shaped conductive patterns are provided facing each other in the peripheral abutment area of ​​the separating surface between a pair of conductive patterns on the insulating substrate, thereby increasing the amount of current flowing between the first conductive pattern and the second conductive pattern on the high stroke side, and increasing the current change. Therefore, it can be said that the input device of Example 2 can suppress the variation between products and increase the output change in the high voltage region.

[0063] <Example 3> In Example 2, four island-shaped conductive patterns formed in a square shape were provided using Ag. The size of the island-shaped conductive patterns was changed so that the size of the island-shaped conductive patterns increased from the conductive elastic member toward the side surface of the insulating substrate in a plan view of the conductive elastic member. The rest of the experiment was performed in the same manner as in Example 1. The measurement results of the current flowing between a pair of conductive patterns while pressing the conductive elastic member are shown in FIG. 198. The measurement results of an input device in which a pair of island-shaped conductive patterns is not arranged are shown as Comparative Example 3.

[0064] 19, the detection positions of the initial resistance values ​​were the same in Example 3 and Comparative Example 3, but the amount of current could be increased stepwise as the stroke was increased in Example 3 compared to Comparative Example 3. This is believed to be because the current flowed more easily between the pair of rectangular island-shaped conductive patterns via the square island-shaped conductive patterns. Also, as the conductive elastic member was deformed by pressure, the area of ​​contact of the conductive elastic member with the island-shaped conductive pattern having a larger area in a plan view became larger, and the amount of current increased stepwise.

[0065] Furthermore, when the current values ​​of multiple input devices manufactured in the same manner as in Example 3 were measured, there was almost no error in the current values ​​measured by each input device, as in Example 1, and the amount of current on the high stroke side was approximately stable and large.

[0066] Therefore, in both of the input devices of Example 3, a pair of island-shaped conductive patterns are provided in a pair of peripheral abutment areas of the separating surface on the insulating substrate, with the size increasing from the conductive elastic member toward the side surface of the insulating substrate, so that the amount of current flowing between the first conductive pattern and the second conductive pattern can be gradually increased and the current change can be increased even on the high stroke side. Therefore, it can be said that the input device of Example 3 can suppress the variation between products and gradually increase the output change in the high voltage region.

[0067] As described above, the embodiment has been described, but the above embodiment is presented as an example, and the present invention is not limited to the above embodiment. The above embodiment can be implemented in various other forms, and various combinations, omissions, substitutions, modifications, etc. can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0068] 1A, 1B Input Device 10 Insulating substrate 11 Isolation plane 20A First Conductive Pattern 20B Second conductive pattern 30 Conductive elastic member 31 Convex end 40A, 40B Island conductive pattern 111 Tip contact area 112 Surrounding area

Claims

1. An insulating substrate; a first conductive pattern and a second conductive pattern provided on the insulating substrate; a conductive elastic member supported on the first conductive pattern and the second conductive pattern so as to be movable toward and away from the insulating substrate, the conductive elastic member having a convex end portion formed in a dome shape, an input device in which, as a pressure contact force of the convex end against the insulating substrate increases, a contact area between the convex end and the first conductive pattern and a contact area between the convex end and the second conductive pattern increase, and electrical resistance between the first conductive pattern and the second conductive pattern decreases, the insulating substrate has an isolation surface that isolates the first conductive pattern and the second conductive pattern so as to be electrically independent of each other; the separating surface has a tip contact area with which the tip of the convex end contacts and a peripheral contact area with which the periphery of the convex end contacts; an input device comprising an island-shaped conductive pattern in the peripheral contact area, the island-shaped conductive pattern being electrically independent from the first conductive pattern and the second conductive pattern;

2. The input device according to claim 1 , wherein the island-shaped conductive pattern is formed in an elongated shape extending in a direction from the tip contact area toward the peripheral contact area.

3. The input device according to claim 1 , wherein the island-shaped conductive pattern is provided in a plurality of discontinuous positions along a direction from the tip contact area to the peripheral contact area.

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