Capacitive input device

Abstract

Provided is a capacitive input device capable of sensing an input made by a user through touch. It has a surface sheet 20, a soft member 30, and a sensor sheet 40 for detecting changes in capacitance. The surface sheet 20 has an operation area 21 for performing a touch operation. The soft member 30 is disposed between the operation area 21 and the sensor sheet 40. The sensor sheet 40 has a sensor electrode 42 at a position corresponding to the operation area 21. When the operation area 21 is pushed in by a touch operation, the surface sheet 20 and the soft member 30 are displaced toward the sensor sheet 40, and capacitance is detected by the sensor electrode 42.

Description

Technical Field

[0001] The disclosure of the present application relates to a capacitive input device. Background Art

[0002] As an input device for an electronic device, a touch input device having a capacitive sensor is known. Such a capacitive input device (capacitive touch input device) detects a change in capacitance generated when a user touches an operation area provided on, for example, a housing of the electronic device with a finger (for example, Patent Document 1).

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2016-081818 Figure 1 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] In an input device of an electronic device, a button switch (physical key) that performs input by physical displacement is also widely used. In an input operation using such a button switch, there is an operation feeling accompanied by physical displacement, so that a user can sense that an input has been made through the sense of touch.

[0008] In contrast, in a capacitive touch input device, since the housing of the electronic device is hard, there is no change in the sense of touch even when touched with a finger, so that it is difficult for the user to confirm that an input operation has been performed.

[0009] Means for Solving the Problems

[0010] Several aspects disclosed in the present application are configured to have the following features.

[0011] That is, one aspect disclosed in the present application is a capacitive input device including a surface member, a soft member, and a sensor sheet that detects a change in capacitance. The surface member has an operation area for performing a touch operation. The soft member is disposed between the operation area and the sensor sheet. The sensor sheet has a sensor electrode at a position corresponding to the operation area. When the operation area is pushed in by a touch operation, the surface member and the soft member are displaced toward the sensor sheet, and the capacitance is detected by the sensor electrode.

[0012] In one aspect of the present disclosure, the capacitive input device has a soft member between the operation area where the user performs a touch operation and the sensor sheet, and the sensor sheet has sensor electrodes at positions corresponding to the operation area. Further, in one aspect of the present disclosure, the capacitive input device is configured such that when the user pushes in the operation area by a touch operation, the surface member and the soft member are displaced toward the sensor sheet, and the capacitance is detected by the sensor electrodes. Therefore, according to one aspect of the present disclosure, the user can sense an input to the capacitive input device by the sense of touch.

[0013] In one aspect of the present disclosure, it can be configured that the soft member has a conductive portion that increases the capacitance value in order to improve the detection sensitivity of a portion between the operation area and the sensor electrodes.

[0014] If a soft member is provided between the operation area and the sensor electrodes, it is necessary to ensure that the distance between the operation area and the sensor electrodes is at least as long as the amount of the soft member, so there is a possibility that the sensitivity and detection accuracy of the sensor are reduced. However, in one aspect of the present disclosure, the soft member has a conductive portion in a portion between the operation area and the sensor electrodes. The conductive material constituting the conductive portion generally tends to have a higher dielectric constant than the insulating material. Further, by increasing the dielectric constant of the soft member, the capacitance value between the finger touching the operation area and the sensor electrodes also becomes larger.

[0015] Therefore, in one aspect of the present disclosure, the capacitive input device can simultaneously have the soft touch of the soft member and the conductivity of the conductive portion. Accordingly, according to one aspect of the present disclosure, while configuring the capacitive input device such that the user can sense an input by the sense of touch, the sensitivity and detection accuracy of the sensor can be improved. Further, in the case where a plurality of pairs of operation areas and sensor electrodes are arranged side by side, it is possible to prevent an input operation to another operation area different from the operation area paired with the sensor electrode from being erroneously detected.

[0016] In one aspect of the present disclosure, it can be configured that the conductive portion is a conductive medium contained in the soft member formed of a polymer matrix.

[0017] In one aspect of the present disclosure, the conductive portion is constituted by a conductive medium contained in a polymer matrix. Therefore, according to one aspect of the present disclosure, the conductive portion can be easily formed with respect to the insulating polymer matrix constituting the soft member.

[0018] In one aspect of the present disclosure, it can be configured that the conductive portion is an alignment portion in which the conductive medium is aligned on the soft member.

[0019] In one aspect of the present disclosure, the conductive portion is constituted by an alignment portion in which the conductive medium is aligned. Therefore, according to one aspect of the present disclosure, even if the concentration of the conductive medium is reduced, it is possible to easily ensure the conductivity between the operation region and the sensor electrode. Further, since the concentration of the conductive medium can be reduced, it is possible to easily ensure the flexibility of the soft member.

[0020] In one aspect of the present disclosure, it can be configured that the soft member is formed of a light-transmissive material that can illuminate the operation region.

[0021] In one aspect of the present disclosure, the soft member is constituted by a light-transmissive material that can illuminate the operation region by, for example, an internal light source disposed near the sensor electrode. Therefore, according to one aspect of the present disclosure, the capacitive input device can clearly display the position of the operation region to the user. Therefore, according to one aspect of the present disclosure, the user can reliably push into the operation region.

[0022] In one aspect of the present disclosure, it can be configured that the operation region has a first operation region and a second operation region, the sensor electrode has a first electrode corresponding to the first operation region and a second electrode corresponding to the second operation region, and the soft member has an insulating portion between a first portion and a second portion, the first portion being located between the first operation region and the first electrode, and the second portion being located between the second operation region and the second electrode.

[0023] In one aspect of the present disclosure, the first portion located between the paired first operation region and the first electrode and the second portion located between the other paired second operation region and the second electrode are separated by an insulating portion. Therefore, according to one aspect of the present disclosure, each sensor electrode can be less affected by regions other than the paired operation regions. Therefore, according to one aspect of the present disclosure, it is possible to improve the sensitivity and detection accuracy of the sensor of the capacitive input device and prevent false detection in the case where the capacitive input device has a plurality of operation regions.

[0024] Further, in one aspect of the present disclosure, the insulating portion makes it difficult for light to pass between the first portion and the second portion. Therefore, in one aspect of the present disclosure, the light incident on the soft member from near the sensor electrode easily reaches the operation region paired with the sensor electrode. Therefore, according to one aspect of the present disclosure, it is possible to intensively illuminate the operation region paired with the sensor electrode. Further, in the case where a plurality of paired operation regions and sensor electrodes are arranged side by side, it is possible to prevent illumination of other regions different from the operation region paired with the sensor electrode.

[0025] In one aspect of the present disclosure, the capacitive input device can be configured to have a first rigid support member on a surface of the sensor sheet opposite to the surface where the soft member is disposed.

[0026] In one aspect of the present disclosure, the first rigid support member supports the soft member via the sensor sheet. Thus, according to one aspect of the present disclosure, the shape of the soft member having flexibility and the thin and easily deformable sensor sheet can be maintained. Further, according to one aspect of the present disclosure, when the operation area is pushed in, the rigid support member generates a reaction force against compressive deformation on the soft member, and the sinking of the soft member and the sensor sheet can be moderately suppressed.

[0027] In one aspect of the present disclosure, the capacitive input device can be configured to have a second rigid support member between the surface member and the sensor sheet, the second rigid support member having a hole, and the soft member being disposed in the hole.

[0028] In one aspect of the present disclosure, the rigid support member surrounds the soft member disposed in the hole. Thus, according to one aspect of the present disclosure, a soft touch can be given to the operation area, and a hard touch can be given to the peripheral area around the operation area. Therefore, according to one aspect of the present disclosure, even if the user does not visually observe the capacitive input device, an input operation can be performed at the correct position.

[0029] In one aspect of the present disclosure, the capacitive input device can be configured to have an outer surface with a three-dimensional shape, and the operation area is formed on the outer surface.

[0030] In one aspect of the present disclosure, the operation area is formed on the outer surface with a three-dimensional shape. Thus, according to one aspect of the present disclosure, the application range of the capacitive input device can be expanded.

[0031] In one aspect of the present disclosure, the capacitive input device can be configured such that the soft member is formed by laminating a plurality of members.

[0032] In one aspect of the present disclosure, the soft member is formed by laminating a plurality of members. Thus, according to one aspect of the present disclosure, the thickness, conductivity, etc. of the soft member can be adjusted.

[0033] In one aspect of the present disclosure, the capacitive input device can be configured such that the plurality of members are a combination of an insulating soft member and a conductive soft member.

[0034] In one aspect of the present disclosure, a soft member formed by laminating an insulating soft member and a conductive soft member is used. Therefore, according to one aspect of the present disclosure, even without adjusting the mixing of the conductive medium of the conductive soft member, it is possible to adjust the reaction load against the pushing operation and the sensor sensitivity (DIFF value). BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a top view of an automobile showing an application example of the operation switch of the first embodiment.

[0036] Figure 2 is a top view showing the appearance of the operation switch of the first embodiment.

[0037] Figure 3 is Figure 2 a cross-sectional view taken along line III-III of

[0038] Figure 4 is a cross-sectional view corresponding to Figure 3 showing the orientation of the conductive medium of the soft member, Figure 4 in which 4A shows spherical particles, Figure 4 in which 4B shows fibrous particles, Figure 4 in which 4C shows long fibrous particles. Figure 4 in which 4D shows non-continuously oriented fibrous particles.

[0039] Figure 5 is a cross-sectional view corresponding to Figure 3 the operation switch of the first modification.

[0040] Figure 6 is a cross-sectional view corresponding to Figure 3 the operation switch of the second modification.

[0041] Figure 7 is a top view showing the appearance of the operation switch of the third modification.

[0042] Figure 8 is Figure 7 a cross-sectional view taken along line VIII-VIII of

[0043] Figure 9 is a top view showing the appearance of the operation switch of the second embodiment.

[0044] Figure 10 is Figure 9 a cross-sectional view taken along line X-X of

[0045] Figure 11 is a front view showing the appearance of the operation switch of the fourth modification.

[0046] Figure 12is the AND of the operation switch of the fourth modification example Figure 10 The corresponding cross-sectional view.

[0047] Figure 13 is Figure 11 The cross-sectional view taken along line XIII-XIII of Figure 13 In 13A, an example of a soft member arranged in a full circle is shown. Figure 13 In 13B, an example of a soft member arranged partially is shown.

[0048] Figure 14 is an external perspective view showing the front, left side, and top surface of the appearance of the operation switch including the third embodiment.

[0049] Figure 15 is Figure 14 The cross-sectional view taken along line XV-XV of

[0050] Figure 16 is the AND of the operation switch of the fifth modification example Figure 15 The corresponding cross-sectional view.

[0051] Figure 17 is Figure 14 The cross-sectional view taken along line XVII-XVII of

[0052] Figure 18 is an explanatory diagram showing the measurement method of the embodiment. Detailed Description of the Invention

[0053] Hereinafter, one aspect of the present disclosure will be described in detail with reference to the drawings. In addition, the embodiments described below do not unduly limit the claims, and not all the structures described in the embodiments are necessarily required as solutions.

[0054] For the structures common to the following embodiments, the same reference numerals are given and repeated descriptions in the specification are omitted. Further, repeated descriptions of the common usage methods and effects of the embodiments are also omitted. Here, in this specification and the claims, when described as "first", "second", "third", "fourth", "fifth", and "sixth", they are used to distinguish different constituent elements, and are not used to represent a specific order, superiority, etc.

[0055] The "capacitive input device" disclosed in the present application is an input device operated by a user to cause a desired function in an electronic device to operate. The electronic device provided with the "capacitive input device" is, for example, installed in a vehicle, and specifically, mounted in a vehicle such as an automobile or a transportation means including rails. As an example, the "capacitive input device" of the present embodiment is an input device of an electronic device disposed on an in-vehicle interior panel provided in an automobile.

[0056] Figure 1 The exemplified vehicle 1 is a right-hand drive vehicle, that is, the driver's seat 2 is located on the right side of the traveling direction, the front passenger seat 3 is located on the left side of the traveling direction, and a steering wheel 4 is provided on the right side of the traveling direction. Various in-vehicle interior panels are provided around the driver's seat 2 and the front passenger seat 3 of the vehicle 1. As the in-vehicle interior panels, as Figure 1 shown, for example, the center console 5, the center cluster 6 in the central part of the instrument panel, and the armrest part 7 of the door can be cited. The in-vehicle interior panel becomes an operation panel for an electronic device. Here, an example of an embodiment of the operation switch 10 of the "capacitive input device" disposed on the center console 5 will be described with reference to the accompanying drawings.

[0057] In this specification and the claims, for convenience, as Figure 2 、 Figure 3 shown, etc., the left-right direction of the operation switch 10 as the "capacitive input device" is referred to as the X direction, the depth (front-rear) direction is referred to as the Y direction, and the height direction (up-down direction) is referred to as the Z direction. Further, in Figure 3 the operation switch 10 shown, one side of the surface sheet 20 as the "surface member" exposed on the surface of the center console 5 is referred to as the upper side (surface layer side) in the Z direction. And one side of the sensor sheet 40 covered by the surface sheet 20 or the like is referred to as the lower side (deep layer side) in the Z direction. However, this does not limit the orientation of the configuration of the operation switch 10, the push-in input operation direction, etc.

[0058] First Embodiment( Figures 1 to 8 )

[0059] As Figure 3 shown, the operation switch 10 has a surface sheet 20, a soft member 30, and a sensor sheet 40 that detects changes in capacitance. The operation switch 10 has a layer shape in which the surface sheet 20, the soft member 30, and the sensor sheet 40 are arranged in sequence from the surface layer side exposed on the surface of the center console 5. Moreover, the operation switch 10 is configured such that when the surface sheet 20 is pushed in from the surface side of the center console 5 by the touch operation of the user, the surface sheet 20 and the soft member 30 are displaced toward the sensor sheet 40 for input. The operation switch 10 of this embodiment has a surface along the XY plane in a rectangular shape that is longer in the X direction than in the Y direction. However, the shape of the operation switch 10 in the XY plane is not particularly limited.

[0060] The surface sheet 20 constitutes the outer surface of the operation switch 10 and is the part that the finger I of the user as the "operating body" touches. As Figure 2As shown, the surface sheet 20 has an operation area 21 and a peripheral area 22. The surface sheet 20 is formed as a thin plate (film, sheet) shape having a thickness (plate thickness) in the Z direction and a surface along the XY plane. The surface sheet 20 has flexibility such that when it is pushed in by a user's touch operation, its operation area 21 can be displaced downward in the Z direction. The surface sheet 20 may also have stretchability.

[0061] The operation area 21 is the part that is pushed in by a user's touch operation when selecting and executing various functions of the electronic device. That is, the operation area 21 is configured as the input part of the operation switch 10. In the operation switch 10 of the present embodiment, when viewed from above, two square operation areas 21 are arranged in parallel along the X direction of the surface sheet 20. At least one operation area 21 may be provided on the operation switch 10, and there is no particular limitation on its number. The operation area 21 is surrounded by the peripheral area 22 when viewed from above.

[0062] On the surface sheet 20, characters, marks, patterns, etc. indicating the position and function of the operation area 21 are displayed. The operation area 21 may be configured to be illuminated by an internal light source (backlight). When the operation area 21 is illuminated, it may be illuminated in such a way that characters, marks, patterns, etc. emit light, or it may be illuminated in such a way that the surrounding area emits light, or the entire operation area 21 may be illuminated. Decorations such as the position, characters, marks, patterns, and light-shielding layer of the operation area 21 are provided on at least one of the front and back surfaces of the surface sheet 20 by painting, printing, etc. The position, characters, marks, patterns, etc. of the operation area 21 may be set by embossing (concave-shaped, convex-shaped characters, etc.). By using embossing to set the concave-convex shape, frame shape, etc. indicating the position of the operation area 21, the user can touch the operation area 21 with their fingertips even when blind-touching.

[0063] Preferably, at least the operation area 21 of the surface sheet 20 is soft. Since the operation area 21 is soft, it can be deformed in such a way that it is displaced downward when pushed in by a user's touch operation. On the other hand, preferably, the surface sheet 20, especially the peripheral area 22, is harder than the soft member 30. By making the peripheral area 22 harder than the soft member 30, the user can distinguish the operation area 21 and the peripheral area 22 even when blind-touching. When the operation area 21 of the operation switch 10 is soft, it is easily achieved by the surface sheet 20 of the operation area 21 being soft and flexible, and further the soft member 30 below it being soft.

[0064] As a flexible material capable of bending and deforming, the surface sheet 20 uses a resin film, a resin sheet, a rubber sheet (film), etc. As the resin sheet (film) that can be used for the surface sheet 20, thermoplastic resins such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), acrylic (AC), and polyvinyl chloride (PVC) can be cited. As the rubber sheet that can be used for the surface sheet 20, synthetic rubbers (thermosetting elastomers) such as silicone and urethane (polyurethane), and thermoplastic elastomers can be cited.

[0065] As the material of the surface sheet 20, in addition, cloth, fabric, non-woven fabric, mesh, mesh sheet, foamed sheet, synthetic leather, etc. can also be used. Thus, the surface sheet 20 becomes a surface presenting the pattern of a fabric such as cloth. In the case where the cloth, etc. is a cloth with a large gap between the constituent fibers, etc., if a soft resin film such as an elastic urethane film or a thin film, or a non-woven fabric with a fine mesh is laminated on the lower surface side of the cloth, etc., there will be no gap, so it is preferred. Thus, the infiltration of the soft member 30 into the surface sheet 20 can be avoided.

[0066] By having a thickness of 0.005 mm or more, the surface sheet 20 can ensure its strength, and by having a thickness of 2 mm or less, it can be easily deformed. Therefore, the surface sheet 20 preferably has a thickness of 0.005 mm to 2 mm, and particularly preferably has a thickness of 0.05 mm.

[0067] The sensor sheet 40 for capacitive input is a capacitive sensor that detects the approach of the user's finger I. The sensor sheet 40 has a base sheet 41, a sensor electrode 42, and a protective layer 43.

[0068] The base sheet 41 is the part that forms the basis of the structure of the sensor sheet 40. The base sheet 41 is formed into a thin plate (sheet) shape having a thickness (plate thickness) in the Z direction and having a surface along the XY plane. The base sheet 41 and the surface sheet 20 are arranged such that their surfaces along the XY plane face each other.

[0069] In the base sheet 41, as a light-transmissive and electrically insulating material, a resin sheet (film), etc. is used. As the resin sheet that can be used for the base sheet 41, thermoplastic resins such as polyethylene terephthalate (PET), polycarbonate (PC), acrylic (AC), and polyimide (PI) can be cited. In the case where the base sheet 41 does not require light transmissivity, a glass fiber epoxy laminate can also be used.

[0070] The sensor electrode 42 is an electrode for generating an electrostatic capacitance with the user's finger I. The sensor electrode 42 is formed in a film shape having a thickness (film thickness) in the Z direction and a surface along the XY plane. On the surface of the base substrate 41 facing the surface sheet 20, the sensor electrode 42 is provided at a position corresponding to the operation area 21. As long as the sensor electrode 42 is at a position corresponding to the operation area 21, it can be formed on the surface of the base substrate 41 facing the surface sheet 20, or can be formed on the back surface. The sensor electrode 42 is connected to the sensor control IC via circuit wirings formed in the base substrate 41.

[0071] The sensor electrode 42 can use metal pastes such as silver, conductive coatings such as carbon paste, and conductive metal foils. Further, the sensor electrode 42 can use PEDOT / PSS (Poly(3,4-EthyleneDiOxyThiophene) / PolyStyreneSulfonate (dispersion of poly(ethylene dioxythiophene) and polystyrene sulfonic acid)), ITO (Indium Tin Oxide), or a paste containing conductive nanoparticles such as nanoscale fine conductive powders and fine conductive fibers. If the sensor electrode 42 is a transparent conductive film using a film, paste, or paste containing conductive nanoparticles of PEDOT / PSS or ITO, it has light transmissivity and can transmit backlight illumination. For the circuit wirings, metal foils, conductive coatings, etc. can also be used in the same manner as the sensor electrode 42.

[0072] The protective layer 43 (resist) is a part that protects the sensor electrode 42 and the circuit wirings. The protective layer 43 is formed in a thin plate (film) shape having a thickness (plate thickness) in the Z direction and a surface along the XY plane. The protective layer 43 is provided on the surfaces of the base substrate 41, the sensor electrode 42, and the circuit wirings facing the surface sheet 20 to cover them. Or, in the case where the sensor electrode 42 and the circuit wirings are provided on the back surface of the base substrate 41, they are covered on the back surface side. The protective layer 43 uses an electrically insulating resin film, resin coating film, etc.

[0073] By having a thickness of 10 μm or more, the sensor sheet 40 can ensure its strength, and by having a thickness of 2500 μm or less, it can make the operation switch 10 thinner while ensuring light transmissivity. Therefore, the sensor sheet 40 preferably has a thickness of 10 μm to 2500 μm.

[0074] The soft member 30 is a part that gives a soft pushing operation feeling to the user who touches the operation area 21. The soft member 30 is disposed between the surface sheet 20 and the sensor sheet 40. The soft member 30 is provided at least between the paired operation areas 21 and the sensor electrodes 42. The soft member 30 is configured to have a thickness (plate thickness) in the Z direction and has a thin plate shape with a surface along the XY plane. The soft member 30 has flexibility that allows deformation downward of the operation area 21 in response to the touch operation of the user.

[0075] According to the operation switch 10 having such a structure, it can function in the following manner. That is, when the operation area 21 is pushed in by a touch operation, the surface sheet 20 and the soft member 30 are displaced toward the sensor sheet 40, and the capacitance is detected by the sensor electrodes 42. Thus, the operation switch 10 has the soft member 30 at least between the paired operation areas 21 and the sensor electrodes 42. Therefore, when the user performs the pushing operation of the operation area 21, a soft touch can be obtained at the fingertips, and an input feeling can be obtained. Moreover, according to the present embodiment, it is possible to make the user perceive that an input has been made to the operation switch 10 through the touch feeling.

[0076] The operation switch 10 of the present embodiment is disposed on the left console 5 with respect to the driver's seat 2 of a right-hand drive vehicle as described above. Therefore, many drivers push in the operation area 21 with the left hand, which is their non-dominant hand. However, in the operation switch 10 of the present embodiment, the operation area 21 is given a soft pushing operation feeling, so the user can touch the operation area 21 even when blindly groping with the left hand, and thus can accurately perform the touch operation.

[0077] In the soft member 30, as a material with an ultra-low hardness, a rubber-like or gel-like polymer matrix, a grease-like soft filler, a soft plate, etc. are used. As a rubber that can be used for the soft member 30, synthetic rubbers such as silicone rubber can be cited. As a gel that can be used for the soft member 30, silicone gel, urethane gel, acrylic gel, hydrogel, etc. can be cited. As a grease that can be used for the soft member 30, oil-based substances such as silicone-based substances can be cited.

[0078] The soft member 30 uses a member with an ultra-low hardness. The soft member 30 preferably has a hardness of A10 or less (a measured value obtained by an A-type durometer conforming to JIS K6253:2012 standard). Further, the soft member 30 preferably has a penetration of 50 or more (a measured value obtained by a penetration tester conforming to JIS K2207:2006 standard). Further, the soft member 30 preferably has a nanoindentation hardness of 10 N / mm 2The hardness of the following (measurement values conforming to ISO14577-1 and JISZ2255:2003 standards). The nanoindentation hardness is obtained based on the test force that causes the indenter to make a depression on the test surface and the surface area of the depression obtained by pushing. It is measured by applying a maximum load of 1 mN (pushing load) for 10000 m seconds. Thus, the soft member 30 can impart a soft pushing operation feeling to the operation area 21.

[0079] By having a thickness of 1 mm or more, the soft member 30 can impart a soft touch feeling and a pushing amount to the fingertips of the user who touches the operation area 21. By having a thickness of 5 mm or less, a decrease in the sensitivity of the sensor can be suppressed. Therefore, the soft member 30 preferably has a thickness of 1 mm to 5 mm, and particularly preferably has a thickness of 2 mm to 3 mm. In this way, the soft member 30 requires a thickness of a certain amount or more in order to impart a soft pushing operation feeling to the user who touches the operation area 21.

[0080] The soft member 30 preferably has a shape recovery property that can recover its original shape without permanent (plastic) deformation when the load is removed. The compression set of the material used for the soft member 30 is preferably 70% or less, and more preferably 50% or less. Thus, the soft member 30 becomes easier to recover its original shape. For the compression set, it can be measured at room temperature after being placed at a temperature of 70 °C for 22 hours in a state of being compressed from the initial thickness to 25% deformation in accordance with JISK6262:2013 standard.

[0081] Here, when the soft member 30 is provided between the operation area 21 and the sensor electrode 42, it is necessary to ensure that the distance between the operation area 21 and the sensor electrode 42 is at least as long as the amount of the soft member, so there is a possibility of a decrease in the sensitivity and detection accuracy of the sensor.

[0082] In response to this, in order to suppress a decrease in the sensitivity and detection accuracy of the sensor, the soft member 30 more preferably has conductivity. Therefore, the soft member 30 can be configured to have a conductive portion 31 in the portion between the operation area 21 and the sensor electrode 42. Generally, the conductive material constituting the conductive portion 31 has a tendency to have a higher dielectric constant than the insulating material. Moreover, by increasing the dielectric constant of the soft member 30, the value of the electrostatic capacitance between the finger I touching the operation area 21 and the sensor electrode 42 also becomes larger. Therefore, the detection value of the electrostatic capacitance sensor becomes larger, so the sensitivity and detection accuracy of the sensor can be improved.

[0083] Thus, in order to improve the detection sensitivity of the portion between the operation area 21 and the sensor electrode 42, the soft member 30 can be configured to have a conductive portion 31 that increases the value of the capacitance. The operation switch 10 having such a structure can simultaneously have the flexibility brought by the soft member 30 and the conductivity brought by the conductive portion 31. Therefore, according to the present embodiment, while constituting the operation switch 10 that enables the user to perceive the input through the sense of touch, the sensitivity and detection accuracy of the sensor can be improved. Further, when a plurality of pairs of operation areas 21 and sensor electrodes 42 are arranged side by side, it is possible to prevent an input operation to an operation area 21 different from the operation area 21 paired with the sensor electrode 42 from being erroneously detected.

[0084] When the soft member 30 has a volume resistivity of, for example, 1.0×10 6 Ω·cm or less, it does not hinder the detectability of the capacitance sensor, and thus is preferably used. More preferably, it has a volume resistivity of 1.0×10 4 Ω·cm or less.

[0085] The conductive portion 31 can be configured to be a conductive medium contained in the soft member 30 formed of, for example, a polymer matrix. Thus, the conductive portion 31 can be easily formed with respect to the insulating polymer matrix constituting the soft member 30.

[0086] Examples of the conductive medium that can be used for the conductive portion 31 include metal powder, carbon powder, graphite powder, conductive polymer powder, ITO powder, etc. When the soft member 30 is a hydrogel, various electrolytes can also be used as the conductive portion 31. In order to form the conductive portion 31 in the soft member 30, in addition to containing the conductive medium in the polymer matrix, the base material itself of the soft member 30 can also use a conductive polymer.

[0087] The soft member 30 is preferably formed of a light-transmitting material that enables the operation area 21 to be illuminated. By forming the soft member 30 of a light-transmitting material, the operation area 21 can be illuminated by an internal light source (backlight) disposed, for example, near the sensor electrode 42. Therefore, the operation switch 10 can clearly display the position of the operation area 21 to the user. Therefore, according to such a structure, the user can accurately push in the operation area 21. When the soft member 30 has a visible light transmittance of 3% or more and 95% or less, the backlight illumination can pass through and the display of characters, marks, patterns, etc. in the operation area 21 can be illuminated, and thus is preferably used.

[0088] As a backlight, a light-emitting element such as an LED (Light Emitting Diode) or a light guide such as a light guide plate can be used to illuminate the display in the operation area 21. The light-emitting element can be arranged below the operation area 21 in the Z direction to illuminate, or can be arranged at a distance such as the side and the light can be guided through the light guide to illuminate the display in the operation area 21.

[0089] The soft member 30 preferably has both conductivity and light transmittance in the portion between the operation area 21 and the sensor electrode 42. That is, by the soft member 30 having conductivity and light transmittance from the sensor electrode 42 toward the operation area 21, even if it has a thickness that gives a soft touch, the detectability of the sensor will not be reduced, and an operation switch 10 that can backlight the display in the operation area 21 can be realized. By using a light-transmissive material as the material of the soft member 30 and the conductive medium, the soft member 30 can have both conductivity and light transmittance at the same time. Even if the conductive medium uses nano-scale fine powder or fine fiber, the soft member 30 can have both conductivity and light transmittance at the same time.

[0090] The conductive portion 31 can be configured as an alignment portion 32 in which the conductive medium is aligned on the soft member 30. For example, as Figure 4 shown in 4A, the conductive medium can be an alignment portion 32 in which spherical particles 33 are aligned in a manner of being connected in the Z direction (thickness direction). Further, for example, as Figure 4 shown in 4B, the conductive medium can also be an alignment portion 32 in which fibrous particles 34 are aligned in a manner of being connected in the Z direction. Moreover, for example, as Figure 4 shown in 4C, the conductive medium can also be an alignment portion 32 in which long fibrous particles 35 are aligned continuously in the Z direction. These spherical particles 33, fibrous particles 34, and long fibrous particles 35 are all conductive media that are more closely arranged in the Z direction than in the XY direction (plane direction) and are conductively connected to each other in the Z direction. Moreover, on the soft member 30, in the portion between the operation area 21 and the sensor electrode 42, a conductive portion 31 having conductivity in the Z direction is formed.

[0091] On the other hand, for example, as Figure 4As shown in 4D in [reference], the conductive medium can also be the oriented portion 32 in which the fibrous particles 36 are oriented in a discontinuous manner in the Z direction. In this case, before the operation area 21 and the soft member 30 are pushed in by a touch operation, the fibrous particles 36 do not contact each other and are not electrically conductive. However, when the operation area 21 and the soft member 30 are pushed in by a touch operation, the fibrous particles 36 come into contact with each other and are electrically connected in the Z direction. Therefore, in this case, in the soft member 30, a conductive portion 31 having conductivity in the Z direction is also formed in the portion between the operation area 21 and the sensor electrode 42.

[0092] The conductive medium is oriented in the Z direction to form the oriented portion 32, and the conductive media are linked and continuously electrically connected to each other. Thus, even if the concentration of the conductive medium is reduced, it is possible to easily ensure the conductivity between the operation area 21 and the sensor electrode 42. In this way, in the soft member 30 in which the conductive portion 31 is formed by the oriented portion 32, since the conductivity is ensured, the conductive medium can be sparsely arranged in the XY direction. Moreover, the conductive medium, which has a tendency to have lower light transmittance compared to, for example, a polymer matrix that is the main material of the soft member 30, can be sparsely arranged in the XY direction, so that the soft member 30 can have high light transmittance in the Z direction. Furthermore, since the concentration of the conductive medium can be reduced, it is possible to easily ensure the flexibility of the soft member 30 and also make the soft member 30 have an ultra-low hardness. The orientation of the conductive medium in the Z direction can be performed by fixing the position in a state where the orientation and the chain configuration of the conductive medium are determined by using a force such as a magnetic field, an electric field, or a flow field.

[0093] The soft member 30 can use a material that has high conductivity and light transmittance in the Z direction and low conductivity and light transmittance in the XY direction, that is, a material in which conductivity and light transmittance are anisotropic. The soft member 30 preferably has a volume resistivity of, for example, 1.0×10 8 Ω·cm or more in the XY direction. Since the soft member 30 has relatively low conductivity in the XY direction, it is difficult for the capacitance sensor to erroneously detect a touch operation on an operation area 21 different from the operation area 21 paired with the sensor electrode 42. The soft member 30 preferably has a visible light transmittance of, for example, less than 3% in the XY direction. Since the soft member 30 has relatively low light transmittance in the XY direction, it is difficult for the non-target operation area 21 to be illuminated by light, and only the target operation area 21 can be highlighted and illuminated brightly.

[0094] In addition, the soft member 30 may be configured such that a conductive soft member having a conductive portion 31 and an insulating soft member without a conductive portion 31 are stacked in the Z direction. At this time, they may be configured to be alternately stacked, or either the conductive soft member or the insulating soft member may be continuously stacked.

[0095] Furthermore, the operation switch 10 can have a structure for holding the surface sheet 20, the soft member 30, etc. The operation switch 10 can be configured to have a first rigid support member 51 on a surface of the sensor sheet 40, for example, on the side opposite to the surface where the soft member 30 is disposed. The first rigid support member 51 is formed in a thin plate (sheet) shape having a thickness (plate thickness) in the Z direction and having a surface along the XY plane. The first rigid support member 51 has the rigidity to support the soft member 30 and the sensor sheet 40 that are to be displaced downward in the Z direction.

[0096] In this way, the first rigid support member 51 supports the soft member 30 via the sensor sheet 40. Therefore, the first rigid support member 51 can maintain the shape of the soft member 30 having flexibility and the thin and easily deformable sensor sheet 40 and can prevent the outflow of the soft member 30 and the sensor sheet 40. Furthermore, when the operation area 21 is pushed in, the first rigid support member 51 generates a reaction force against the compressive deformation of the soft member 30, and can moderately suppress the sinking of the soft member 30 and the sensor sheet 40, thereby maintaining the desired soft touch.

[0097] First modification example ( Figure 5 )

[0098] Furthermore, as Figure 5 shown, the operation switch 10A can be configured to have a second rigid support member 52 between the surface sheet 20 and the sensor sheet 40, for example. The second rigid support member 52 has a hole, and the soft member 30 is disposed in the hole. The second rigid support member 52 is formed in a thin plate (sheet) shape having a thickness (plate thickness) in the Z direction and having a surface along the XY plane. Moreover, on the second rigid support member 52, holes penetrating in the Z direction are formed at positions corresponding to the sensor electrodes 42. That is, the operation switch 10A here separately disposes the soft member 30 on the sensor electrodes 42, and has a configuration in which the periphery of the soft member 30 is surrounded by the frame-shaped second rigid support member 52. Thus, the soft member 30 is disposed only between the operation area 21 and the sensor sheet 40.

[0099] In this way, the second rigid support member 52 surrounds the soft member 30 disposed in the hole. Therefore, the second rigid support member 52 can position the soft member 30 from the side. Furthermore, the second rigid support member 52 can impart a soft tactile sensation to the operation area 21 and a rigid tactile sensation to the peripheral area 22 around the operation area 21. Therefore, according to one aspect of the present disclosure, even if the user does not visually observe the operation switch 10A, an input operation can be performed at the correct position.

[0100] Second Modified Example( Figure 6 )

[0101] Furthermore, as Figure 6 shown, the operation switch 10B can be configured such that, for example, a third rigid support member 53 is provided on the surface of the peripheral area 22 of the surface sheet 20 facing the soft member 30. The third rigid support member 53 is formed in a thin plate (sheet) shape having a thickness (plate thickness) in the Z direction and a surface along the XY plane. Moreover, a hole penetrating in the Z direction is formed in the third rigid support member 53 at a position corresponding to the operation area 21. That is, the operation switch 10B here is configured such that the peripheral area 22 of the surface sheet 20 and the third rigid support member 53 are laminated. As a result, compared with the operation area 21, the rigid member in the peripheral area 22 is thicker than the soft member 30 in the Z direction.

[0102] In this way, the third rigid support member 53 hardens the peripheral area 22 by increasing the thickness of the rigid member in the peripheral area 22. Therefore, the third rigid support member 53 can impart a soft tactile sensation to the operation area 21 and a rigid tactile sensation to the peripheral area 22 around the operation area 21. Therefore, according to one aspect of the present disclosure, even if the user does not visually observe the operation switch 10B, an input operation can be performed at the correct position. The third rigid support member 53 preferably has a thickness of, for example, 0.5 mm, as it can harden the peripheral area 22.

[0103] The first rigid support member 51 and the second rigid support member 52 can be made of a rigid thermoplastic resin, a rigid thermosetting resin, synthetic rubber, a thermoplastic elastomer, or the like. The materials used for the first rigid support member 51 and the second rigid support member 52 are preferably electrically insulating. In particular, the first rigid support member 51 is preferably made of a light-transmissive material so that the backlight can pass through.

[0104] In addition, the first rigid support member 51 can also be combined with any one of the second rigid support member 52 and the third rigid support member 53.

[0105] Third modified example( Figures 7 to 8 )

[0106] As Figure 7 andFigure 8 As shown, in the operation switch 10C of the third modification example, an insulating groove 37 can be configured as an "insulating portion" for preventing erroneous detection with an adjacent operation area 21. Here, the operation area 21 has a first operation area 21A and a second operation area 21B. Further, the sensor electrode 42 has a first electrode 42A corresponding to the first operation area 21A and a second electrode 42B corresponding to the second operation area 21B. Moreover, the soft member 30 has an insulating groove 37 that forms a gap between a first portion 38A and a second portion 38B. The first portion 38A is located between the first operation area 21A and the first electrode 42A, and the second portion 38B is located between the second operation area 21B and the second electrode 42B. The insulating groove 37 has a groove width in the X direction and has a rectangular cross-section when viewed from the side.

[0107] In this way, the first portion 38A located between the paired first operation area 21A and the first electrode 42A and the second portion 38B located between the other paired second operation area 21B and the second electrode 42B are separated by the insulating groove 37. The conductivity becomes extremely low between the first portion 38A and the second portion 38B separated by the insulating groove 37. Therefore, each sensor electrode 42 can be hardly affected by areas other than the paired operation areas 21. Therefore, according to the structure in which the soft member 30 has the insulating groove 37, while improving the sensitivity and detection accuracy of the sensor of the operation switch 10C, erroneous detection in the case where the operation switch 10C has multiple operation areas 21 can be prevented.

[0108] Further, the insulating groove 37 makes it difficult for light to pass between the first portion 38A and the second portion 38B. Therefore, the light incident on the soft member 30 from the vicinity of the sensor electrode 42 easily reaches the operation area 21 paired with the sensor electrode 42. Therefore, according to the structure in which the soft member 30 has the insulating groove 37, the operation area 21 paired with the sensor electrode 42 can be illuminated intensively. Further, in the case where multiple paired operation areas 21 and sensor electrodes 42 are arranged side by side, illumination of other operation areas 21 different from the operation area 21 paired with the sensor electrode 42 can be prevented.

[0109] The insulating groove 37 serving as the "insulating portion" that separates the first portion 38A and the second portion 38B is not limited to a gap and can also be made of a material different from that of the soft member 30. The "insulating portion" can use electrically insulating gels, rubbers, resins, etc. With the "insulating portion" formed of such materials, it is also possible to make it difficult for each sensor electrode 42 to be affected by areas other than the paired operation areas 21. Therefore, while improving the sensitivity and detection accuracy of the sensors of the operation switch 10C, it is possible to prevent false detection in the case where the operation switch 10C has multiple operation areas 21. Similarly, with the "insulating portion" formed of electrically insulating gels, rubbers, resins, etc., it is also possible to irradiate the operation area 21 paired with the sensor electrode 42 intensively. Furthermore, in the case where multiple paired operation areas 21 and sensor electrodes 42 are arranged side by side, it is possible to prevent irradiation of other operation areas 21 different from the operation area 21 paired with the sensor electrode 42.

[0110] Second Embodiment( Figures 9 to 13 )

[0111] The operation switches 10, 10A, 10B, and 10C as the "capacitive input device" are not limited to the form buried under the flat surface sheet 20 without unevenness, and can also be applied to an electronic device having a three-dimensional shaped outer surface and an input portion. That is, the operation switch 10D of the present embodiment has a three-dimensional shaped outer surface, and the operation area 21 is formed on the outer surface. As Figure 9 and Figure 10 shown, the surface sheet 20 has a three-dimensional shaped surface in the shape of a cylinder. Moreover, the operation area 21 is provided on the top surface of the cylinder. Here, the sensor sheet 40 is arranged upside down compared with the first embodiment. That is, the sensor sheet 40 is arranged such that the base sheet 41 faces the soft member 30. On the surface of the sensor sheet 40 opposite to the surface facing the soft member 30, a disk-shaped first rigid support member 51 is provided.

[0112] Thus, in the present embodiment, the operation area 21 is formed on the three-dimensional shaped outer surface. Therefore, according to the present embodiment, the application range of the operation switch 10 can be expanded. The three-dimensional shape provided with the operation area 21 is not limited to the cylindrical shape, and various three-dimensional shapes such as a convex surface, a concave surface, a prism shape, a frustum of a cone shape, a frustum of a pyramid shape, and a ring shape can be provided, for example.

[0113] Fourth Modified Example( Figures 11 to 13 )

[0114] The outer surface formed with the operation area 21 is not limited to the top surface of the three-dimensional shape. In Figure 11 and Figure 12In the operation switch 10E of the fourth modified example shown, an operation area 21 is provided on the side surface (outer peripheral surface) of a cylindrical shape. The operation areas 21 are provided at four locations at 90° intervals in the circumferential direction. On the radially inner side of the operation area 21, a base material sheet 41 is provided in a concentric circle shape with the surface sheet 20. Moreover, on the inner peripheral surface of the base material sheet 41, sensor electrodes 42 are respectively provided at positions corresponding to the respective operation areas 21 in the radial direction. A soft member 30 is provided between the surface sheet 20 and the base material sheet 41.

[0115] As Figure 13 shown in 13A in, the soft member 30 may also be continuously arranged in a cylindrical shape. On the other hand, as Figure 13 shown in 13B in, the soft member 30 may also be provided at four locations at 90° intervals in the circumferential direction corresponding to the operation area 21 and the sensor electrodes 42. In this case, a frame-shaped fourth rigid support member 54 is provided between the adjacent soft members 30.

[0116] In this way, in the present embodiment, the operation area 21 is formed on the side surface (outer peripheral surface) of a three-dimensional shape. Therefore, according to the present embodiment, the applicable range of the present disclosure can be expanded to an input device of an electronic device such as the operation switch 10E that is pushed in a direction intersecting the direction from the top surface downward.

[0117] The sensor sheet 40 here is arranged with the front and back reversed compared to the first embodiment. That is, the sensor sheet 40 is arranged such that the base material sheet 41 faces the soft member 30. However, the sensor sheet 40 of the present embodiment may also be arranged in the same direction as the first embodiment.

[0118] Third Embodiment ( Figures 14 to 17 )

[0119] The "capacitive input device" can be configured such that the outer packaging member 60 (housing) around it is continuously connected to the surface, and the surface sheet 20 widely covers the outer surface of the electronic device. That is, as Figure 14 shown in etc., the surface sheet 20 of the present embodiment continuously covers the entire surfaces of the operation switches 10 (representing the operation switch 10F and the operation switch 10H) arranged in parallel and the outer packaging member 60, thereby constituting the outer surface of the electronic device.

[0120] Figure 15The operation switch 10F of the third embodiment shown is configured such that the edge of the exterior member 60 protrudes from the outer surface of the exterior member 60 via a minute gap. The sensor electrode 42 is not shown in the figure. The operation switch 10F is configured such that the entire top surface of the protruding surface sheet 20 becomes the operation area 21. The soft member 30 is formed in a disc shape. Moreover, the soft member 30 is supported by the top surface of the fifth rigid support member 55 so as to be entirely disposed on the back side of the surface sheet 20 in the area of the operation switch 10F. A sensor sheet 40 is provided on the surface of the fifth rigid support member 55 on the side opposite to the surface on which the soft member 30 is disposed. Alternatively, the sensor sheet 40 may be provided between the fifth rigid support member 55 and the soft member 30.

[0121] Fifth Modified Example( Figure 16 )

[0122] Figure 16 The soft member 30 of the operation switch 10G of the fifth modification shown is formed in a hollow cylindrical shape. The surface sheet 20 is directly supported by the fifth rigid support member 55. Moreover, the soft member 30 is supported by the outer peripheral surface of the fifth rigid support member 55 so as to be entirely disposed on the inner peripheral surface side of the side surface of the surface sheet 20.

[0123] Sixth Modification Example( Figure 17 )

[0124] Figure 17 The operation switch 10H of the sixth modification shown is configured such that the edge of the exterior member 60 does not protrude from the outer surface of the exterior member 60 via a minute gap. That is, the surface sheet 20 is provided to be flat in the areas of both the operation switch 10H and the exterior member 60. The soft member 30 is formed in a rectangular flat plate shape. Moreover, the soft member 30 is supported by the top surface of the sixth rigid support member 56 so as to be entirely disposed on the back side of the surface sheet 20 in the area of the operation switch 10H. A sensor sheet 40 is provided on the surface of the sixth rigid support member 56 on the side opposite to the surface on which the soft member 30 is disposed. Alternatively, the sensor sheet 40 may be provided between the sixth rigid support member 56 and the soft member 30.

[0125] In the operation switch 10F etc. of the present embodiment, the operation switch 10F etc. and the exterior member 60 are continuously covered by a single surface sheet 20. Therefore, according to the operation switch 10F etc. of the present embodiment, a seamless appearance without gaps and seams between the surface members can be obtained.

[0126] If the surface sheet 20 is soft or sufficiently thin, the surface sheet 20 in the gap between the operation switch 10F or the like and the exterior member 60 can also perform a pushing operation on the operation area 21 of the operation switch 10F or the like relative to the exterior member 60 by stretching or bending. However, the surface sheet 20 at the portion adjacent to the soft member 30 has a pushing feel due to the compression deformation of the soft member 30, and thus it may not be configured such that the surface sheet 20 deforms relative to the exterior member 60 by the pushing operation of the operation area 21.

[0127] In the "capacitive input device" disclosed in the present application, the structures shown in the respective embodiments and modification examples can be freely combined within a range without causing contradictions. For example, the second rigid support member 52, the third rigid support member 53, etc. of the first embodiment can also be combined with the structure of the second embodiment.

[0128] In addition, although the respective embodiments have been described in detail as above, for those skilled in the art, it is easy to understand that various modifications can be made that do not substantially depart from the new matters and effects of the present invention. Therefore, all such modification examples are included in the scope of the present invention.

[0129] Examples

[0130] Hereinafter, examples are shown to more specifically and in detail describe the operation switch 10 and the like of the "capacitive input device" as the present embodiment. However, the present embodiment is not limited to the following examples.

[0131] The operation switch used in the examples is Figure 3 the operation switch 10 configured with the surface sheet 20, the sensor sheet 40, and the soft member 30 therebetween as shown in etc. The surface sheet 20 uses a soft polyurethane sheet with a thickness of 0.05 mm. The sensor sheet 40 uses a sensor sheet in which a plurality (two or more) of sensor electrodes 42 and circuit wirings formed on a base sheet 41 are covered with a protective layer 43. As the base sheet 41, a PET sheet with a thickness of 0.1 mm is used. The plurality of sensor electrodes 42 are conductive coatings formed using PEDOT / PSS conductive paste. Further, the circuit wirings are conductive coatings formed using a paste containing silver powder. As the protective layer 43, an electrically insulating resin coating is formed.

[0132] As the soft member 30, for each of the structural examples shown in Table 1, a member formed by combining a member made of one material or members of different materials is used. The soft member 30 here is provided so as to straddle and cover two adjacent sensor electrodes 42. The total thickness of the entire soft member 30 is prepared to be 3 mm.

[0133] Measure the volume resistivity [Ω·cm] in the thickness direction (Z direction) and the surface direction (XY direction) of each prepared soft member 30. The volume resistivity is obtained by multiplying the resistance value [Ω] measured in the thickness direction and the surface direction of the soft member 30 by the cross-sectional area and dividing by the length, respectively. The resistance value is measured using a digital multimeter (R6552 manufactured by ADVANTEST Corporation). When measuring the resistance value of a member having a thickness of 1.0 mm as in Structural Example 2 described later, five sheets are overlapped in the thickness direction so that the total thickness becomes 0.5 cm, and then the resistance value is measured.

[0134] As Figure 18 shown, after each obtained operation switch 10 is placed on the measurement table S, various measurements are performed. For each operation switch 10, a pressing member P that mimics the finger I of a person as an "operating body" is pressed against the central portion of each sensor electrode 42 from above as a measuring member, and the reaction load [N] and the sensor sensitivity of each sensor electrode 42 with respect to the pushing-in distance (stroke) [mm] are measured. The pressing member P is made of conductive rubber having a hardness of A60 and is formed in a cylindrical shape with a diameter of 6 mm. The reaction load is detected by a force sensor connected to the pressing member P having the above-mentioned conductive rubber at the tip.

[0135] Here, various materials are involved in the material used for the soft member 30 in this embodiment. Therefore, with respect to the pushing-in distance of 1.0 mm for each soft member 30, the reaction load at the time when the soft member 30 is compressed by 33% is defined as the unified hardness index of this embodiment. Moreover, if the reaction load at the time of this 33% compression is 6 N or less, it is preliminarily confirmed as a low load and a soft touch, and thus it is preferable as the material of the soft member 30.

[0136] The sensor sensitivity of each sensor electrode 42 is measured by connecting the terminal of the sensor sheet 40 that is electrically connected to the sensor electrode 42 to a control IC (Integrated Circuit). As the control IC, a PSoC (registered trademark) IC (microcomputer CY8C24894 56-pin QFN (Quad Flat Non-leaded package) manufactured by Cypress Semiconductor Corporation) is used. The following settings are used for the parameters of the PSoC IC: Resolution is 12 bit (4096), ReFValue is 2, Prescaler Period is 3, Scanning Speed is Normal, and PRSPolynomial is Short.

[0137] As an index indicating the sensor sensitivity of each sensor electrode 42, a DIFF value [-] based on the change amount of the electrostatic capacitance is used. Here, the DIFF value is the difference between the detected value (RAW value) of the electrostatic capacitance and the baseline value (DIFF value = measured value (RAW value) - baseline value). For each operation switch 10, the DIFF value of the sensor electrode 42 corresponding to the operation area 21 where the pusher P is located and the DIFF value of the other sensor electrodes 42 adjacent to the sensor electrode 42 of the operation object are measured.

[0138] (Structural Example 1)

[0139] In Structural Example 1, the soft member 30 uses a non-conductive gel as the insulating soft member. As the non-conductive gel, a two-component addition reaction type silicone gel (TSE3070 manufactured by Momentive Performance Materials Inc.) is used. The soft member 30 of Structural Example 1 is an insulating silicone gel having a volume resistivity of 1 × 10 15 Ω·cm, and the volume resistivity values in the thickness direction and the surface direction can be regarded as substantially the same. Furthermore, the penetration of the silicone gel after hardening is 65, which belongs to low hardness. Moreover, the silicone gel is colorless and transparent and has good light transmittance.

[0140] (Structural Example 2)

[0141] In Structural Example 2, the soft member 30 uses a conductive gel as the conductive soft member. The conductive gel uses an adhesive pad for a low-frequency therapeutic apparatus (HV-PAD-3 manufactured by Omron Healthcare Co., Ltd.) using a conductive hydrogel. The hydrogel uses a non-woven fabric as the intermediate substrate. The resistance value of the soft member 30 of Structural Example 2 is 3 × 10 5 Ω, and the volume resistivity is 6 × 10 5 Ω·cm, and the volume resistivity values in the thickness direction and the surface direction can be regarded as substantially the same. Moreover, the hydrogel has good light transmittance. The soft member 30 of Structural Example 2 is arranged by laminating 3 sheets of the same sheet-shaped adhesive layer having a thickness of 1.0 mm. Therefore, the overall thickness of the soft member 30 is 3 mm.

[0142] (Structural Example 3)

[0143] In Structural Example 3, the non-conductive gel of Structural Example 1 and the conductive gel of Structural Example 2 are combined and used for the soft member 30. Here, the soft member 30 is laminated in such a manner that the conductive gel is disposed in the upper layer on the surface sheet 20 side and the non-conductive gel is disposed in the lower layer on the sensor electrode 42 side. The thickness of the silicone gel is formed to be 2 mm, and a hydrogel having a thickness of 1.0 mm is laminated thereon. Therefore, the overall thickness of the soft member 30 of Structural Example 3 is 3 mm. The volume resistivity of the soft member 30 of Structural Example 3 is 1×10 15 Ω·cm, and the values of the volume resistivity in the thickness direction and in the surface direction of the lower layer side where the non-conductive gel is disposed can be regarded as being substantially the same. Thus, since the volume resistivity of the lower layer side of the soft member 30 becomes a high value, the influence on the sensitivity of the adjacent sensor electrode 42 becomes small.

[0144] (Structural Example 4)

[0145] In Structural Example 4, as the soft member 30, an anisotropic conductive gel is used, that is, after mixing a conductive medium in an insulator (non-conductor) base material, by orienting the conductive medium in the thickness direction of the soft member 30, an anisotropic conductive gel having higher conductivity in the thickness direction than in the surface direction of the soft member 30 is obtained. The base material of the anisotropic conductive gel uses the same two-component addition reaction type silicone gel (TSE3070 manufactured by Momentive Performance Materials Inc.) as in the above Structural Example 1. As the conductive filler as the substance for imparting conductivity, silver-plated nickel powder having an average particle diameter of 30 μm formed by plating silver on the base material nickel is used.

[0146] The soft member 30 of Structural Example 4 is formed by mixing silver-plated nickel powder in an insulating silicone gel and crosslinking and curing it after applying a magnetic field in a certain direction. Thus, as the soft member 30 of Structural Example 4, an anisotropic conductive silicone gel sheet having an orientation portion 32 is obtained, and the orientation portion 32 is formed by continuously arranging silver-plated nickel particles in the thickness direction of the sheet-shaped member having a thickness of 3 mm. Moreover, the volume resistivity of the soft member 30 of Structural Example 4 in its thickness direction is 1.5×10 -1 Ω·cm, and the volume resistivity in its surface direction is 1×10 8 Ω·cm.

[0147] (Structural Example 5)

[0148] In Structural Example 5, as the soft member 30, an insulating rubber of an insulator (non-conductor) is used. The insulating rubber uses a rubber obtained by curing a two-liquid component type liquid silicone rubber (KE-1950-10A / B manufactured by Shin-Etsu Chemical Co., Ltd.) by an addition reaction. The soft member 30 of Structural Example 5 has a volume resistivity of 1×1015 Insulating silicone rubber with an electrical insulation of Ω·cm, and the volume resistivity values in the thickness direction and the surface direction can be regarded as approximately the same. Furthermore, this silicone rubber has a hardness of A10, which is a low hardness. Also, the thickness of the soft member 30 in Structural Example 5 is adjusted to 3 mm.

[0149] (Comparative Example)

[0150] In the comparative example, as the member corresponding to the soft member 30, an insulating rubber (non-conductor) is used. The insulating rubber is a rubber obtained by curing a two-liquid component type liquid silicone rubber (KE-1950-20A / B produced by Shin-Etsu Chemical Co., Ltd.) through an addition reaction. In the comparative example, the hardness of the member corresponding to the soft member 30 in the above Structural Example 5 is A20. Other than this, it is the same as the above Structural Example 5.

[0151] [Table 1]

[0152]

[0153] Reaction Load and DIFF Value

[0154] (Structural Example 1)

[0155] In Structural Example 1, the reaction load against the pushing operation varies at a relatively low value. That is, in Structural Example 1, even when the pushing distance becomes 1.0 mm (compressed by 33%), the reaction load is only 0.1 N, which is significantly lower than 6 N, maintaining a low-load state. Therefore, from Structural Example 1, it can be seen that a soft pushing operation feeling is imparted.

[0156] On the other hand, in Structural Example 1, when the pushing distance exceeds a predetermined amount, the DIFF value suddenly becomes a relatively high value. That is, the DIFF value in Structural Example 1 is 57.4 when the pushing distance is 0.2 mm, less than 100 even when the pushing distance is 0.5 mm, and 447 when the pushing distance is 1.0 mm. Furthermore, although it is a relatively low level compared to the sensor electrode 42 of the operation object, the DIFF value is also detected in other adjacent sensor electrodes 42. However, in response to this, by setting thresholds such as a DIFF value of 100 and 40% of the maximum value of the DIFF value, it is possible to detect only the operation on the desired sensor electrode 42.

[0157] From the above results, it can be seen that in Structural Example 1, the operation switch 10 has a good pressure-sensitive characteristic, having a soft touch at the initial stage of pushing and detecting the operation through a certain amount of pushing.

[0158] (Structural Example 2)

[0159] In Structural Example 2, the reaction load increases in response to the pushing distance with high sensitivity. That is, the reaction load in Structural Example 2 is 0.2 N when the pushing distance is 0.2 mm, and 1.8 N when the pushing distance is 1.0 mm (compressed by 33%). Thus, the value of the reaction load in Structural Example 2 is higher than that in Structural Example 1, presumably due to the influence of the non-woven fabric contained in the soft member 30. However, the reaction load of the soft member 30 in Structural Example 2 is much lower than 6 N when compressed by 33%. Therefore, from Structural Example 2, it can be seen that the reaction to the pushing operation is maintained at a low load state, providing a soft and good touch feeling.

[0160] On the other hand, in Structural Example 2, the DIFF value also increases in response to the pushing distance with high sensitivity. That is, the DIFF value in Structural Example 2 is already 95 at the time when the pushing distance is 0.2 mm, and 440 when the pushing distance is 1.0 mm. Therefore, from Structural Example 2, it can be seen that even a small pushing distance can detect the pushing operation. Furthermore, in Structural Example 2, almost no DIFF value is detected in other adjacent sensor electrodes 42.

[0161] From the above results, it can be seen that in Structural Example 2, highly reliable detection can be performed, that is, the operation is detected only in a narrow range corresponding to the desired sensor electrode 42, namely the pushed part, and no detection is performed in other adjacent sensor electrodes 42. Moreover, it can be seen that this high reliability can be achieved even in a small range of pushing distance.

[0162] (Structural Example 3)

[0163] In Structural Example 3, the reaction load varies at a value lower than that in Structural Example 2. That is, the reaction load in Structural Example 3 is 0.04 N when the pushing distance is 0.2 mm, and even when the pushing distance is 1.0 mm, it is 0.5 N, which is much lower than 6 N. Therefore, from Structural Example 3, it can be seen that the reaction load can be reduced, providing a soft pushing operation feeling.

[0164] On the other hand, in Structural Example 3, the DIFF value increases in response to the pushing distance with high sensitivity. That is, the DIFF value in Structural Example 3 is already 210 at the time when the pushing distance is 0.2 mm, and 503 when the pushing distance is 1.0 mm. Therefore, from Structural Example 3, it can be seen that even a small pushing distance can detect the pushing operation. Furthermore, in Structural Example 3, the DIFF value in other adjacent sensor electrodes 42 is maintained below 100.

[0165] Based on the above results, in Structural Example 3, compared with Structural Example 2 in which the soft member 30 uses a conductive gel, the reaction load against the pushing operation can be reduced. Furthermore, it can be seen that in Structural Example 3, compared with Structural Example 1 in which the soft member 30 uses a non-conductive gel, even at the initial stage of pushing with a small pushing distance, the DIFF value shows a high value, and the pushing operation can be detected. Thus, it can be seen from Structural Example 3 that even if the mixing of the conductive medium is not adjusted in the conductive gel such as in Structural Example 2, the reaction load against the pushing operation and the sensor sensitivity (DIFF value) can be adjusted by the combination of the members laminated on the soft member 30.

[0166] (Structural Example 4)

[0167] In Structural Example 4, the reaction load is a value higher than that in Structural Example 1. That is, the reaction load in Structural Example 4 is 3.4 N when the pushing distance is 1.0 mm (compression 33%). Thus, the reaction load of Structural Example 4 is a value higher than the reaction load of Structural Example 1, and it is presumed to be affected by the conductive medium contained in the soft member 30. However, the reaction load when the soft member 30 in Structural Example 4 is compressed by 33% is much lower than 6 N. Therefore, it can be seen from Structural Example 4 that the reaction against the pushing operation is maintained at a low load state, and the touch feeling is soft and good.

[0168] On the other hand, in Structural Example 4, the DIFF value responds acutely to the pushing distance and becomes a high value. That is, the DIFF value in Structural Example 4 is already 291 at the time point when the pushing distance is 0.2 mm, and is 525 when the pushing distance is 1.0 mm. Therefore, it can be seen from Structural Example 4 that even a small pushing distance can detect the pushing operation. Furthermore, in Structural Example 4, almost no DIFF value is detected in the other adjacent sensor electrodes 42.

[0169] Based on the above results, it can be seen that in Structural Example 4, since the soft member 30 has anisotropic conductivity, the sensor sensitivity of the sensor electrode 42 in the thickness direction of the soft member 30 where the orientation portion 32 extends and the volume resistivity is low is high for the operation area 21 where the pushing operation is performed. On the other hand, in Structural Example 4, it can be seen that the sensor sensitivity of the other sensor electrodes 42 adjacent to the sensor electrode 42 of the operation object is extremely low. Therefore, in Structural Example 4, it can be seen that a more reliable detection can be achieved, that is, the operation is detected only in a narrow range corresponding to the desired sensor electrode 42, that is, the pushed portion, and no detection is performed in the other adjacent sensor electrodes 42. Moreover, it can be seen that this high reliability can be achieved even in a small pushing distance range.

[0170] (Structural Example 5)

[0171] In Structural Example 5, the reaction load is a value higher than that of other structural examples. That is, the reaction load in Structural Example 5 is 5.2 N when the pushing distance is 1.0 mm (compression of 33%). However, the reaction load when the soft member 30 in Structural Example 5 is compressed by 33% is 6 N or less. Therefore, according to Structural Example 5, the reaction to the pushing operation is maintained at a low load state, and the touch feeling is soft and good.

[0172] On the other hand, in Structural Example 5, when the pushing distance exceeds a predetermined amount, the DIFF value rapidly becomes a high value. That is, the DIFF value of Structural Example 5 is 65.6 when the pushing distance is 0.2 mm, but is 447 when the pushing distance is 1.0 mm. Furthermore, although it is at a lower level compared to the sensor electrode 42 of the operation object, the DIFF value is also detected in other adjacent sensor electrodes 42. However, by setting a threshold value such as a DIFF value of 100 or 40% of the maximum value of the DIFF value, it is possible to detect only the operation on the desired sensor electrode 42.

[0173] From the above results, it can be seen that in Structural Example 5, the reaction load to the pushing operation is low and the touch feeling is soft, and by setting an appropriate threshold value for the DIFF value, the pushing operation can be reliably detected.

[0174] (Comparative Example)

[0175] In the comparative example, the reaction load is a value higher than that of each structural example. That is, the reaction load in the comparative example is 9.3 N when the pushing distance is 1.0 mm (compression of 33%). Therefore, the reaction load when the member corresponding to the soft member 30 in the comparative example is compressed by 33% is not 6 N or less. Therefore, in the comparative example, the reaction to the pushing operation is not maintained at a low load state, and the touch feeling cannot be made soft.

[0176] The following insights can be obtained from the above embodiments.

[0177] From the results of Structural Example 2 and Structural Example 4, it can be confirmed that when using a conductive gel as the soft member 30, the sensor sensitivity of the sensor electrode 42 corresponding to the operation region 21 becomes high, and conversely, the influence on other sensor electrodes 42 adjacent to the sensor electrode 42 of the operation object is small. Furthermore, from the results of Structural Example 4, it can be confirmed that when using a gel having anisotropic conductivity with higher conductivity in the thickness direction than in the plane direction as the soft member 30, this tendency becomes further larger, and only the sensor electrode 42 corresponding to the operation region 21 reacts.

[0178] On the other hand, based on the results of Structural Example 1, Structural Example 3, and Structural Example 5, it was confirmed that when there is a non-conductive material in the layer structure of the soft member 30, other sensor electrodes 42 adjacent to the sensor electrode 42 of the operation object sometimes react simultaneously. Moreover, according to the results of Structural Example 1, when a non-conductive gel is used as the soft member 30, the sensor sensitivity does not increase in a region with a low reaction load and it is difficult to detect, and in addition, the tendency for other adjacent sensor electrodes 42 to react simultaneously becomes higher.

[0179] Description of Reference Numerals

[0180] 1: Automobile

[0181] 2: Driver's Seat

[0182] 3: Passenger Seat

[0183] 4: Steering Wheel

[0184] 5: Center Console

[0185] 6: Central Instrument Cluster

[0186] 7: Armrest Portion of Door

[0187] 10: Operation Switch (Capacitive Input Device)

[0188] 10A: Operation Switch (First Modified Example) (Capacitive Input Device)

[0189] 10B: Operation Switch (Second Modified Example) (Capacitive Input Device)

[0190] 10C: Operation Switch (Third Modified Example) (Capacitive Input Device)

[0191] 10D: Operation Switch (Second Embodiment) (Capacitive Input Device)

[0192] 10E: Operation Switch (Fourth Modified Example) (Capacitive Input Device)

[0193] 10F: Operation Switch (Third Embodiment) (Capacitive Input Device)

[0194] 10G: Operation Switch (Fifth Modified Example) (Capacitive Input Device)

[0195] 10H: Operation Switch (Sixth Modified Example) (Capacitive Input Device)

[0196] 20: Surface Sheet (Surface Member)

[0197] 21: Operation Area

[0198] 21A: First operation area

[0199] 21B: Second operation area

[0200] 22: Peripheral area

[0201] 30: Soft member

[0202] 31: Conductive part

[0203] 32: Alignment part

[0204] 33: Spherical particles

[0205] 34: Fiber-shaped particles

[0206] 35: Long fiber-shaped particles

[0207] 36: Fiber-shaped particles

[0208] 37: Insulation groove (insulation part)

[0209] 38A: First part

[0210] 38B: Second part

[0211] 40: Sensor sheet

[0212] 41: Substrate sheet

[0213] 42: Sensor electrode

[0214] 42A: First electrode

[0215] 42B: Second electrode

[0216] 43: Protective layer

[0217] 51: First rigid support member

[0218] 52: Second rigid support member

[0219] 53: Third rigid support member

[0220] 54: Fourth rigid support member

[0221] 55: Fifth rigid support member

[0222] 56: Sixth rigid support member

[0223] 60: Exterior member

[0224] I: Finger (operating body)

[0225] P: Pusher

[0226] S: Measuring table

[0227] X: Left - right direction

[0228] Y: Front - back direction

[0229] Z: Height direction, up - down direction

Claims

1. An electrostatic capacitance type input device, wherein, comprising: a surface member, a soft member, and a sensor sheet for detecting a change in electrostatic capacitance; the surface member has an operation area for performing a touch operation, the soft member is disposed between the operation area and the sensor sheet, the sensor sheet has sensor electrodes at positions corresponding to the operation area, when the operation area is pushed in by a touch operation, the surface member and the soft member are displaced toward the sensor sheet, and the electrostatic capacitance is detected by the sensor electrodes; the operation area has a first operation area and a second operation area, the sensor electrodes have a first electrode corresponding to the first operation area and a second electrode corresponding to the second operation area, the soft member has an insulating portion between a first portion and a second portion, the first portion being located between the first operation area and the first electrode, and the second portion being located between the second operation area and the second electrode.

2. An electrostatic capacitance type input device, wherein, comprising: a surface member, a soft member, and a sensor sheet for detecting a change in electrostatic capacitance; the surface member has an operation area for performing a touch operation, the soft member is disposed between the operation area and the sensor sheet, the sensor sheet has sensor electrodes at positions corresponding to the operation area, when the operation area is pushed in by a touch operation, the surface member and the soft member are displaced toward the sensor sheet, and the electrostatic capacitance is detected by the sensor electrodes; a second rigid support member is provided between the surface member and the sensor sheet, the second rigid support member having a hole, the soft member is disposed in the hole.

3. An electrostatic capacitance type input device, wherein, comprising: a surface member, a soft member, and a sensor sheet for detecting a change in electrostatic capacitance; the surface member has an operation area for performing a touch operation, the soft member is disposed between the operation area and the sensor sheet, the sensor sheet has sensor electrodes at positions corresponding to the operation area, when the operation area is pushed in by a touch operation, the surface member and the soft member are displaced toward the sensor sheet, and the electrostatic capacitance is detected by the sensor electrodes; the electrostatic capacitance type input device has a second rigid support member between the surface member and the sensor sheet, the soft member is configured such that the periphery of the soft member is surrounded by the frame-shaped second rigid support member in a manner of being positioned from the side of the soft member.

4. An electrostatic capacitance type input device, wherein, comprising: a surface member, a soft member, and a sensor sheet for detecting a change in electrostatic capacitance; the surface member has an operation area for performing a touch operation, the soft member is disposed between the operation area and the sensor sheet, the sensor sheet has sensor electrodes at positions corresponding to the operation area, when the operation area is pushed in by a touch operation, the surface member and the soft member are displaced toward the sensor sheet, and the electrostatic capacitance is detected by the sensor electrodes; The capacitive input device has a third rigid support member on a surface facing the soft member in a peripheral area of the operation area of the surface member.

5. An electrostatic capacitance type input device, wherein, It has: a surface member, a soft member, and a sensor sheet that detects changes in capacitance; The surface member has an operation area for performing a touch operation, The soft member is disposed between the operation area and the sensor sheet, The sensor sheet has sensor electrodes at positions corresponding to the operation area, When the operation area is pushed in by a touch operation, the surface member and the soft member are displaced toward the sensor sheet, and the capacitance is detected by the sensor electrodes; The soft member has a conductive portion inside, The conductive portion increases the capacitance value in order to improve the detection sensitivity of a portion between the operation area and the sensor electrodes; The conductive portion is a conductive medium contained in the soft member formed of a polymer matrix; The conductive portion is an orientation portion in which the conductive media are oriented on the soft member.

6. The capacitive input device according to claim 5, wherein The orientation portion is oriented in such a manner that a plurality of the conductive media are linked in the thickness direction of the soft member.

7. The capacitive input device according to claim 5, wherein The orientation portion is oriented in such a manner that the conductive media are discontinuous, When the operation area is pushed in by a touch operation, the conductive media come into contact with each other and are conductively connected.

8. The capacitive input device according to any one of claims 1 to 5, wherein The soft member is formed of a light-transmissive material that allows the operation area to be illuminated.

9. The capacitive input device according to any one of claims 1 to 5, wherein A first rigid support member is provided on a surface of the sensor sheet opposite to the surface on which the soft member is disposed.

10. The capacitive input device according to any one of claims 1 to 5, wherein It has a three-dimensional outer surface, The operation area is formed on the outer surface.

11. The capacitive input device according to any one of claims 1 to 5, wherein The soft member is formed by laminating a plurality of members.

12. The capacitive input device according to claim 11, wherein The plurality of members are members formed by combining an insulating soft member and a conductive soft member.

13. The capacitive input device according to any one of claims 1 to 5, wherein The soft member is a gel-like polymer matrix.

14. The capacitive input device according to any one of claims 1 to 5, wherein The soft member has a plate thickness in the thickness direction of the soft member and has a thin plate shape with a plane along a direction intersecting the thickness direction.

15. The capacitive input device according to any one of claims 1 to 5, wherein The soft member has a thickness of 1 mm to 5 mm.

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