Capacitive Input Device

Abstract

The objective of the present invention is to provide an electrostatic capacitance type input device which makes it possible to perceive by touch that a user has made an input. This electrostatic capacitance type input device is provided with a top surface sheet 20, a soft member 30, and a sensor sheet 40 for detecting a change in electrostatic capacitance, wherein: the top surface sheet 20 includes operating regions 21 for performing a touch operation; the soft member 30 is disposed between the operating regions 21 and the sensor sheet 40; the sensor sheet 40 includes sensor electrodes 42 in positions corresponding to the operating regions 21; and when the operating regions 21 are pushed in by means of a touch operation, the top surface sheet 20 and the soft member 30 are displaced toward the sensor sheet 40, and the electrostatic capacitance is detected by the sensor electrodes 42.

Description

[Technical field]

[0001] The present disclosure relates to capacitive input devices. [Background technology]

[0002] As an input device for electronic devices, a touch input device equipped with a capacitance sensor is known. Such a capacitance type input device (capacitive touch input device) detects a change in capacitance caused by a user touching an operation area arranged on the housing of an electronic device with a finger (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-081818 A, FIG. 1 Summary of the Invention [Problem to be solved by the invention]

[0004] Push button switches (physical keys) that are physically displaced to input are also widely used as input devices for electronic devices. When using such push button switches to input, the user can sense the input by touch, since there is a feeling of operation associated with the physical displacement.

[0005] In contrast, in the case of a capacitive touch input device, the housing of the electronic device is hard and there is no change in the tactile sensation when touched with a finger, making it difficult for the user to confirm that an input operation has been performed. [Means for solving the problem]

[0006] Some aspects disclosed in this application are configured to have the following features.

[0007] That is, one aspect disclosed in the present application is a capacitance-type input device comprising a surface member, a soft member, and a sensor sheet that detects changes in capacitance, the surface member having an operation area for touch operation, the soft member being disposed between the operation area and the sensor sheet, the sensor sheet having a sensor electrode at a position corresponding to the operation area, and when the operation area is pressed 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.

[0008] In one aspect of the present disclosure, the capacitive input device includes a soft member between an operation area that is touched by a user and a sensor sheet having a sensor electrode at a position corresponding to the operation area. In one aspect of the present disclosure, the capacitive input device is configured such that when a user presses the operation area by touching, the surface member and the soft member are displaced toward the sensor sheet, and the capacitance is detected by the sensor electrode. Therefore, according to one aspect of the present disclosure, the user can sense by touch that an input has been made to the capacitive input device.

[0009] In one aspect of the present disclosure, the soft member can be configured to have a conductive portion that increases the value of capacitance to improve detection sensitivity in the portion between the operation area and the sensor electrode.

[0010] If a soft member is provided between the operation area and the sensor electrode, the distance between the operation area and the sensor electrode must be increased by at least that amount, which may result in a decrease in the sensitivity and detection accuracy of the sensor. However, in one aspect of the present disclosure, the soft member has a conductive portion between the operation area and the sensor electrode. The conductive material constituting the conductive portion generally tends to have a higher dielectric constant than an insulating material. In addition, by increasing the dielectric constant of the soft member, the value of the capacitance between the finger touching the operation area and the sensor electrode also increases.

[0011] Therefore, in one aspect of the present disclosure, the capacitive input device can have both a soft tactile sensation due to the soft member and conductivity due to the conductive part. Therefore, according to one aspect of the present disclosure, the capacitive input device can be configured to allow the user to sense the input by touch, while improving the sensitivity and detection accuracy of the sensor. Furthermore, when a plurality of pairs of operation areas and sensor electrodes are arranged side by side, it is possible to prevent erroneous detection of an input operation for an operation area other than the operation area to which the sensor electrode is paired.

[0012] In one aspect of the present disclosure, the conductive portion can be configured to be a conductive medium contained in the soft member made of a polymer matrix.

[0013] In one aspect of the present disclosure, the conductive portion is composed of a conductive medium contained in a polymer matrix, and therefore, according to one aspect of the present disclosure, the conductive portion can be easily formed in the insulating polymer matrix that constitutes the soft member.

[0014] In one aspect of the present disclosure, the conductive portion can be configured to be an orientation portion in which the conductive medium is oriented in the soft member.

[0015] In one aspect of the present disclosure, the conductive portion is configured by an orientation portion in which the conductive medium is oriented. Therefore, according to one aspect of the present disclosure, even if the concentration of the conductive medium is reduced, the conductivity between the operation area and the sensor electrode can be easily ensured. Furthermore, since the concentration of the conductive medium can be reduced, the flexibility of the soft member can be easily ensured.

[0016] In one aspect of the present disclosure, the soft member can be configured such that the operation area is formed of a translucent material that can be illuminated.

[0017] In one aspect of the present disclosure, the soft member is made of a light-transmitting material that can illuminate the operation area by an internal light source disposed near the sensor electrode, for example. Therefore, according to one aspect of the present disclosure, the capacitive input device can clearly indicate the position of the operation area to the user. Therefore, according to one aspect of the present disclosure, the user can reliably press the operation area.

[0018] In one aspect of the present disclosure, the operation area has a first operation area and a second operation area, the sensor electrode has a first electrode corresponding to the first operation area and a second electrode corresponding to the second operation area, and the soft member can be configured to have an insulating portion between a first portion located between the first operation area and the first electrode and a second portion located between the second operation area and the second electrode.

[0019] In one aspect of the present disclosure, a first portion located between a first operation area and a first electrode of a pair and a second portion located between a second operation area and a second electrode of another pair are separated by an insulating portion. Therefore, according to one aspect of the present disclosure, each sensor electrode is less susceptible to influences other than the operation area of ​​the pair. Therefore, according to one aspect of the present disclosure, the sensitivity and detection accuracy of the sensor of the capacitive input device can be improved, and erroneous detection can be prevented when the capacitive input device has multiple operation areas.

[0020] Furthermore, 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, light incident on the soft member from the vicinity of the sensor electrode is likely to reach the operation area paired with the sensor electrode. Therefore, according to one aspect of the present disclosure, it is possible to intensively illuminate the operation area paired with the sensor electrode. Furthermore, when a plurality of pairs of operation areas and sensor electrodes are arranged side by side, it is possible to prevent the sensor electrode from illuminating an area other than the operation area paired with the sensor electrode.

[0021] In one aspect of the present disclosure, the capacitive input device can be further configured to have a first hard support member on a surface of the sensor sheet opposite to the surface on which the soft member is arranged.

[0022] In one aspect of the present disclosure, the first hard support member supports the soft member via the sensor sheet. Therefore, according to one aspect of the present disclosure, the shape of the flexible soft member and the thin and easily deformable sensor sheet can be maintained. Furthermore, according to one aspect of the present disclosure, when the operation area is pressed, the hard support member generates a repulsive force against the compressive deformation in the soft member, and the sinking of the soft member and the sensor sheet can be appropriately suppressed.

[0023] In one aspect of the present disclosure, the capacitive input device may further include a second rigid support member having a hole between the surface member and the sensor sheet, and the soft member may be configured to be disposed in the hole.

[0024] In one aspect of the present disclosure, the hard support member surrounds the soft member disposed in the hole. Therefore, according to one aspect of the present disclosure, a soft tactile sensation can be imparted in the operation area and a hard tactile sensation can be imparted in the peripheral area around the operation area. Therefore, according to one aspect of the present disclosure, the user can perform an input operation at a correct position even if he or she does not visually check the capacitive input device.

[0025] In one aspect of the present disclosure, the capacitive input device can be configured to have a three-dimensional outer surface, and the operation area can be formed on the outer surface.

[0026] According to one aspect of the present disclosure, the operation area is formed on the outer surface of the three-dimensional shape, which makes it possible to expand the range of application of the capacitive input device.

[0027] 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.

[0028] According to one aspect of the present disclosure, the soft member is formed by laminating a plurality of members, and therefore, according to one aspect of the present disclosure, it is possible to adjust the thickness, conductivity, etc. of the soft member.

[0029] In one aspect of the present disclosure, the capacitive input device can be configured such that the plurality of members are a combination of insulating soft members and conductive soft members.

[0030] In one embodiment of the present disclosure, a soft member in which an insulating soft member and a conductive soft member are laminated is used. Therefore, according to one embodiment of the present disclosure, the repulsive load and the sensor sensitivity (DIFF value) for the pressing operation can be adjusted without adjusting the composition of the conductive medium of the conductive soft member. [Brief description of the drawings]

[0031] [Figure 1] 1 is a plan view of an automobile showing an application example of an operation switch according to a first embodiment. [Diagram 2] FIG. 2 is a plan view showing the appearance of the operation switch according to the first embodiment. [Diagram 3] Cross-sectional view of line III-III in Figure 2. [Figure 4] 4A shows a cross-sectional view of the conductive medium of the soft member, corresponding to FIG. 3, in which FIG. 4A shows spherical particles, FIG. 4B shows fiber-shaped particles, FIG. 4C shows long fiber-shaped particles, and FIG. 4D shows discontinuously oriented fiber-shaped particles. [Diagram 5] 4 is a cross-sectional view of an operation switch according to a first modified example, the cross-sectional view corresponding to FIG. 3; [Figure 6] 7 is a cross-sectional view of an operation switch according to a second modified example, the cross-sectional view corresponding to FIG. 3. [Figure 7] FIG. 13 is a plan view showing the appearance of an operation switch according to a third modified example. [Figure 8] Cross-sectional view taken along line VIII-VIII in Figure 7. [Figure 9] FIG. 11 is a plan view showing the appearance of an operation switch according to a second embodiment. [Figure 10] Cross-sectional view taken along line XX in Figure 9. [Figure 11]FIG. 13 is a front view showing the appearance of an operation switch according to a fourth modified example. [Figure 12] 10 , showing a cross-sectional view of an operation switch according to a fourth modified example. [Figure 13] 13A is a cross-sectional view taken along line XIII-XIII in FIG. 11, and FIG. 13B is an example in which a soft member is arranged around the circumference, and FIG. 13B is an example in which a soft member is arranged partially. [Figure 14] FIG. 11 is a front, left side, and plan view showing the appearance of an operation switch according to a third embodiment. [Figure 15] Cross-sectional view of line XV-XV in Figure 14. [Figure 16] 15, showing a cross-sectional view of an operation switch according to a fifth modified example. FIG. [Figure 17] Cross-sectional view of line XVII-XVII in Figure 14. [Figure 18] FIG. 4 is an explanatory diagram showing a measurement method in an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Hereinafter, one embodiment of the present disclosure will be described in detail with reference to the drawings. Note that the present embodiment described below does not unduly limit the scope of the claims, and all of the configurations described in the present embodiment are not necessarily essential as a solution.

[0033] The same reference numerals are used to designate configurations common to the following embodiments, and duplicated explanations in the specification are omitted. Furthermore, duplicated explanations of the usage methods and effects common to the embodiments are also omitted. Herein, when the terms "first," "second," "third," "fourth," "fifth," and "sixth" are used in this specification and claims, they are used to distinguish different components, and are not used to indicate a specific order, superiority, or inferiority.

[0034] The "capacitive input device" disclosed in this application is an input device operated by a user to activate a desired function in an electronic device. An electronic device in which the "capacitive input device" is arranged is provided, for example, in a vehicle, and more specifically, is mounted on a vehicle including an automobile, a train, and the like. The "capacitive input device" of this embodiment is, as an example, an input device for an electronic device arranged on an interior panel for mounting on an automobile.

[0035] The automobile 1 illustrated in FIG. 1 is a right-hand drive vehicle with a driver's seat 2 on the right side of the traveling direction, a passenger seat 3 on the left side of the traveling direction, and a steering wheel 4 on the right side of the traveling direction. Various in-vehicle interior panels are provided around the driver's seat 2 and passenger seat 3 of the automobile 1. As shown in FIG. 1, examples of the in-vehicle interior panels include a center console 5, a center cluster 6 in the center of the instrument panel, and an armrest portion 7 of a door. The in-vehicle interior panels are operation panels for electronic devices. Here, an example of an embodiment of an operation switch 10 as a "capacitive input device" arranged in the center console 5 will be described with reference to the drawings.

[0036] For convenience, in this specification and claims, as shown in Figs. 2, 3, etc., the left-right direction of the operation switch 10 as a "capacitive input device" is described as the X direction, the depth (front-back) direction is described as the Y direction, and the height (up-down) direction is described as the Z direction. Furthermore, in the operation switch 10 shown in Fig. 3, the side of the surface sheet 20 as a "surface member" exposed on the surface of the center console 5 is described as the upper side (surface side) in the Z direction. And the side of the sensor sheet 40 that is shielded by the surface sheet 20, etc. is described as the lower side (deep side) in the Z direction. However, these do not limit the arrangement direction of the operation switch 10, the push input operation direction, etc.

[0037] First embodiment (Figs. 1 to 8)

[0038] As shown in Fig. 3, the operation switch 10 includes a surface sheet 20, a soft member 30, and a sensor sheet 40 that detects changes in capacitance. The operation switch 10 has a layered shape in which the surface sheet 20, the soft member 30, and the sensor sheet 40 are arranged in this order from the surface layer side exposed on the surface of the center console 5. The operation switch 10 is configured so that when the surface sheet 20 is pressed from the surface side of the center console 5 by a touch operation by a user, the surface sheet 20 and the soft member 30 are displaced toward the sensor sheet 40 to perform an input. The operation switch 10 of this embodiment is a rectangular XY plane that is longer in the X direction than in the Y direction. Surface along However, the operation switch 10 has an XY plane. Surface along There is no particular limitation on the shape.

[0039] The top sheet 20 constitutes the outer surface of the operation switch 10 and is the portion that is contacted by the user's finger I as an "operating object." As shown in FIG. 2, the top sheet 20 has an operation area 21 and a peripheral area 22. The top sheet 20 has a thickness (plate thickness) in the Z direction and is in the form of a thin plate (film, sheet) having a surface along the XY plane. The top sheet 20 has flexibility that allows it to deform so that the operation area 21 is displaced downward in the Z direction when pressed by a user's touch operation. The top sheet 20 may be stretchable.

[0040] The operation area 21 is a portion that is pressed by a user through a touch operation when various functions of the electronic device are selected and executed. That is, the operation area 21 is configured as an input section of the operation switch 10. In the operation switch 10 of this embodiment, two operation areas 21 each having a square shape in a plan view are provided side by side along the X direction of the surface sheet 20. There is no particular limit to the number of operation areas 21, as long as one or more operation areas 21 are provided in the operation switch 10. The operation area 21 is surrounded by a peripheral area 22 in a plan view.

[0041] On the surface sheet 20, characters, symbols, 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, the characters, symbols, patterns, etc. may be illuminated so that they shine, the surroundings may be illuminated so that they shine, or the entire operation area 21 may be illuminated. Decorations such as the position of the operation area 21, characters, symbols, patterns, and light-shielding layers are provided on at least one of the front and back surfaces of the surface sheet 20 by painting, printing, etc. The position of the operation area 21, characters, symbols, patterns, etc. may be provided by embossing (concave or convex characters, etc.). By providing a concave-convex shape, frame shape, etc. indicating the position of the operation area 21 by embossing, the user can find the operation area 21 with his / her fingertips even when feeling around (blind touch).

[0042] It is preferable that at least the operation area 21 of the surface sheet 20 is soft. By making the operation area 21 soft, it can be deformed so as to be displaced downward when pressed by a touch operation by a user. On the other hand, it is more preferable that the surface sheet 20, particularly 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 between the operation area 21 and the peripheral area 22 even by feeling around. The operation area 21 of the operation switch 10 is easily made soft by making the surface sheet 20 of the operation area 21 soft and flexible, and further making the soft member 30 below it soft.

[0043] For the top sheet 20, a resin film, a resin sheet, a rubber sheet (film), etc. are used as a flexible material that can be bent and deformed. Examples of resin sheets (films) that can be used for the top sheet 20 include thermoplastic resins such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), acrylic (AC), polyvinyl chloride (PVC), etc. Examples of rubber sheets that can be used for the top sheet 20 include synthetic rubbers (thermosetting elastomers) such as silicone and urethane (polyurethane), thermoplastic elastomers, etc.

[0044] Other materials that can be used for the top sheet 20 include fabric, woven fabric, nonwoven fabric, netting, mesh sheet, foam sheet, synthetic leather, etc. This allows the top sheet 20 to have a surface with the ground pattern of the fabric, etc. When the fabric, etc. has large gaps between the constituent fibers, etc., it is preferable to layer a soft resin film such as an elastic urethane film or a thin film, or a finely woven nonwoven fabric, etc., on the underside of the fabric, etc., to eliminate the gaps. This allows the soft member 30 To surface sheet 20 It is possible to avoid seepage.

[0045] The top sheet 20 can ensure its strength by having a thickness of 0.005 mm or more, and can be easily deformed by having a thickness of 2 mm or less. Therefore, the top sheet 20 preferably has a thickness of 0.005 mm to 2 mm, and particularly preferably has a thickness of 0.05 mm.

[0046] The sensor sheet 40 for performing capacitive input is a capacitive sensor that detects the approach of a user's finger I. The sensor sheet 40 has a base sheet 41, a sensor electrode 42, and a protective layer 43.

[0047] The base sheet 41 is a fundamental part of the structure of the sensor sheet 40. The base sheet 41 has a thickness (plate thickness) in the Z direction and is in the form of a thin plate (sheet) having a surface along the XY plane. The base sheet 41 and the top sheet 20 are arranged so that their surfaces along the XY plane face each other.

[0048] A resin sheet (film) or the like is used as an electrically insulating material having translucency for the base sheet 41. Examples of resin sheets that can be used for the base sheet 41 include thermoplastic resins such as polyethylene terephthalate (PET), polycarbonate (PC), acrylic (AC), and polyimide (PI). If translucency is not required for the base sheet 41, a glass fiber epoxy resin laminate can also be used.

[0049] The sensor electrode 42 is an electrode for generating capacitance between itself and the user's finger I. The sensor electrode 42 has a thickness (film thickness) in the Z direction and is in the form of a film having a surface along the XY plane. The sensor electrode 42 is provided on the surface of the base sheet 41 facing the top sheet 20 at a position corresponding to the operation area 21. The sensor electrode 42 may be formed on the surface of the base sheet 41 facing the top sheet 20 or on the back surface, as long as the position corresponds to the operation area 21. The sensor electrode 42 is connected to a sensor control IC via circuit wiring formed on the base sheet 41.

[0050] The sensor electrode 42 may be made of a metal paste such as silver, a conductive coating such as carbon paste, or a conductive metal foil. / PolyStyrene Sulfonate (a dispersion of polyethylenedioxythiophene and polystyrene sulfonic acid), ITO (Indium Tin Oxide), or a paste containing conductive nanoparticles such as nanoscale fine conductive powder or fine conductive fibers can be used. If the sensor electrode 42 is a transparent conductive film using a thin film or paste of PEDOT / PSS or ITO, or a paste containing conductive nanoparticles, it has translucency and can transmit backlight illumination. For the circuit wiring, metal foil, conductive coating film, etc. can be used as in the sensor electrode 42.

[0051] The protective layer 43 (resist) is a portion that protects the sensor electrodes 42 and the circuit wiring. The protective layer 43 has a thickness (plate thickness) in the Z direction and is in the form of a thin plate (film) having a surface along the XY plane. The protective layer 43 is provided on the surfaces of the base sheet 41, the sensor electrodes 42, and the circuit wiring that face the surface sheet 20, and covers them. Alternatively, when the sensor electrodes 42 and the circuit wiring are provided on the back surface of the base sheet 41, the protective layer 43 covers them on the back surface side. The protective layer 43 is made of an electrically insulating resin film, a resin coating, or the like.

[0052] By having a thickness of 10 μm or more, the strength of the sensor sheet 40 can be ensured, and by having a thickness of 2500 μm or less, the light transmittance can be ensured and the operating switch 10 can be made thin. For this reason, the sensor sheet 40 preferably has a thickness of 10 μm to 2500 μm.

[0053] The soft member 30 is a portion that gives a soft pressing operation feeling to a user who touches the operation area 21. The soft member 30 is disposed between the top sheet 20 and the sensor sheet 40. The soft member 30 is provided at least between a pair of the operation area 21 and the sensor electrode 42. The soft member 30 has a thickness (plate thickness) in the Z direction and is in the shape of a thin plate having a surface along the XY plane. The soft member 30 has flexibility that allows the operation area 21 to deform downward in response to a touch operation by the user.

[0054] According to the operation switch 10 having such a configuration, when the operation area 21 is pressed by a touch operation, the top sheet 20 and the soft member 30 are displaced toward the sensor sheet 40, and the sensor electrode 42 can detect the capacitance. In this manner, the operation switch 10 is provided with the soft member 30 between at least a pair of the operation area 21 and the sensor electrode 42. Therefore, when the operation area 21 is pressed, the user feels a soft touch on the fingertip, and can feel an input. According to this embodiment, the user can feel the input to the operation switch 10 by touch.

[0055] As described above, the operation switch 10 of this embodiment is disposed on the center console 5 to the left of the driver's seat 2 of a right-hand drive vehicle. For this reason, many drivers press the operation area 21 with their left hand, which is their non-dominant hand. However, in the operation switch 10 of this embodiment, a flexible pressing operation feeling is imparted to the operation area 21, so that the user can find the operation area 21 with their left hand and can reliably touch and operate it, even by feeling around.

[0056] For the soft member 30, a rubber-like or gel-like polymer matrix, a grease-like soft filler, a soft plate, or the like is used as a material with ultra-low hardness. Examples of rubber that can be used for the soft member 30 include synthetic rubber such as silicone rubber. Examples of gels that can be used for the soft member 30 include silicone gel, urethane gel, acrylic gel, hydrogel, and the like. Examples of grease that can be used for the soft member 30 include oil-based grease such as silicone-based grease.

[0057] A member with an ultra-low hardness is used for the soft member 30. The soft member 30 preferably has a hardness of A10 or less (measured with a type A durometer conforming to JIS K 6253:2012). Furthermore, the soft member 30 more preferably has a hardness of a penetration of 50 or more (measured with a penetration tester conforming to JIS K 2207:2006). Furthermore, the soft member 30 preferably has a nanoindentation hardness of 10 N / mm2 It is more preferable that the soft member 30 has a hardness of the following value (measured value in accordance with ISO14577-1 and JIS Z 2255:2003). The nanoindentation hardness is calculated from the test force applied to the test surface with an indenter to make an indentation and the surface area of ​​the indentation, and is measured by applying a maximum indentation load (pressing load) of 1 mN, which is the test force, for 10,000 ms. This allows the soft member 30 to give the operation area 21 a soft feeling of pressing operation.

[0058] The soft member 30 has a thickness of 1 mm or more, so that it can provide a soft tactile sensation and a pressing amount to the fingertip of the user who touches the operation area 21, and has a thickness of 5 mm or less, so that it can suppress a decrease in the sensitivity of the sensor. For this reason, 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. Thus, the soft member 30 needs to have a thickness of a certain amount or more in order to provide a soft pressing operation feeling to the user who touches the operation area 21.

[0059] The soft member 30 preferably has a shape restoring property that returns to its original shape without permanent (plastic) deformation when unloaded. The compression set of the material used for the soft member 30 is preferably 70% or less, and more preferably 50% or less. This makes it easier for the soft member 30 to return to its original shape. The compression set can be measured at room temperature after compressing the material to a 25% strain from its initial thickness in accordance with JIS K 6262:2013 and leaving it at a temperature of 70°C for 22 hours.

[0060] Here, if a 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 that much longer, which may result in a decrease in the sensitivity and detection accuracy of the sensor.

[0061] On the other hand, it is more preferable that the soft member 30 has conductivity in order to suppress a decrease in the sensitivity and detection accuracy of the sensor. For this reason, the soft member 30 can be configured to have a conductive portion 31 in a portion between the operation area 21 and the sensor electrode 42. The conductive material constituting the conductive portion 31 generally tends to have a higher dielectric constant than an insulating material. By increasing the dielectric constant of the soft member 30, the value of the capacitance between the finger I touching the operation area 21 and the sensor electrode 42 also increases. Therefore, the detection value of the capacitance sensor increases, and the sensitivity and detection accuracy of the sensor can be improved.

[0062] In this way, the soft member 30 can be configured to have a conductive portion 31 that increases the capacitance value in order to increase the detection sensitivity in the portion between the operation area 21 and the sensor electrode 42. The operation switch 10 having such a configuration can have both flexibility due to the soft member 30 and conductivity due to the conductive portion 31. Therefore, according to this embodiment, the operation switch 10 can be configured to allow the user to sense the input by touch, while improving the sensitivity and detection accuracy of the sensor. Furthermore, when a plurality of pairs of the operation area 21 and the sensor electrode 42 are arranged side by side, it is possible to prevent erroneous detection of an input operation to an operation area 21 other than the operation area 21 with which the sensor electrode 42 is paired.

[0063] The soft member 30 has a thickness of, for example, 1.0×10 6 A volume resistivity of 1.0×10 Ω·cm or less is preferable because it does not impede the detection performance of the capacitance sensor. 4 It is more preferable that the volume resistivity is Ω·cm or less.

[0064] The conductive portion 31 can be configured to be a conductive medium contained in the soft member 30 made of, for example, a polymer matrix. This makes it possible to easily form the conductive portion 31 in the insulating polymer matrix that constitutes the soft member 30.

[0065] Examples of conductive media 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 and the like can also be used for the conductive portion 31. In order to form the conductive portion 31 in the soft member 30, a conductive polymer may be used for the base material of the soft member 30 itself, other than including a conductive medium in a polymer matrix.

[0066] The soft member 30 is preferably formed of a light-transmitting material that can illuminate the operation area 21. By forming the soft member 30 from a light-transmitting material, it becomes possible to illuminate the operation area 21 by an internal light source (backlight) disposed near the sensor electrode 42, for example. Therefore, the operation switch 10 can clearly indicate the position of the operation area 21 to the user. Therefore, with such a configuration, the user can reliably press the operation area 21. It is preferable that the soft member 30 has a visible light transmittance of 3% or more and 95% or less, so that the backlight illumination can pass through and illuminate the display of the operation area 21, such as characters, symbols, patterns, etc.

[0067] For backlight illumination, light emitting elements such as LEDs (Light Emitting Diodes) and light guides such as light guide plates can be used to illuminate the display in the operation area 21. The light emitting elements may be disposed below the operation area 21 in the Z direction to illuminate it, or may be disposed far away, such as to the side, and the light guide may guide the light to illuminate the display in the operation area 21.

[0068] It is preferable that the soft member 30 has both electrical conductivity and translucency in the portion between the operation area 21 and the sensor electrode 42. That is, by having the electrical conductivity and translucency from the sensor electrode 42 toward the operation area 21, even if the soft member 30 has a thickness that gives a soft tactile sensation, the detection ability of the sensor is not reduced, and the operation switch 10 that can illuminate the display of the operation area 21 with a backlight can be realized. By using a translucent material as the material of the soft member 30 and the conductive medium, the soft member 30 can have both electrical conductivity and translucency. By using nanoscale fine powder or fine fiber as the conductive medium, the soft member 30 can also have both electrical conductivity and translucency.

[0069] The conductive portion 31 can be configured as an orientation portion 32 in which a conductive medium is oriented in the soft member 30. The conductive medium may be, for example, as shown in FIG. 4A, an orientation portion 32 in which spherical particles 33 are oriented so as to be chained in the Z direction (thickness direction). Furthermore, the conductive medium may be, for example, as shown in FIG. 4B, an orientation portion 32 in which fibrous particles 34 are oriented so as to be chained in the Z direction. And, the conductive medium may be, for example, as shown in FIG. 4C, an orientation portion 32 in which long fiber-shaped particles 35 are oriented so as to be continuous in the Z direction. These spherical particles 33, fibrous particles 34, and long fiber-shaped particles 35 are all densely arranged in the Z direction compared to the XY directions (plane directions), and are electrically connected to each other in the Z direction. And, in the soft member 30, a conductive portion 31 having conductivity in the Z direction is formed in a portion between the operation area 21 and the sensor electrode 42.

[0070] On the other hand, the conductive medium is an orientation portion 32 in which fiber-shaped particles 36 are discontinuously oriented in the Z direction, as shown in FIG. 4D. EvenIn this case, before the operation area 21 and the soft member 30 are pressed in by a touch operation, the fibrous particles 36 are not in contact with each other and are not electrically connected. However, when the operation area 21 and the soft member 30 are pressed in by a touch operation, the fibrous particles 36 come in contact with each other and are electrically connected in the Z direction. Therefore, even in this case, the conductive portion 31 having electrical conductivity in the Z direction is formed in the soft member 30 in the portion between the operation area 21 and the sensor electrode 42.

[0071] The conductive medium is oriented in the Z direction to form the orientation section 32, and the conductive media are connected in a chain and continuous manner, so that the conductivity between the operation area 21 and the sensor electrode 42 can be easily ensured even if the concentration of the conductive medium is reduced. In this way, the soft member 30 in which the conductive section 31 is formed by the orientation section 32 ensures conductivity, so that the conductive medium can be sparsely arranged in the XY direction. In addition, the conductive medium, which tends to have low translucency compared to, for example, the 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 also have high translucency in the Z direction. Furthermore, since the concentration of the conductive medium can be reduced, the flexibility of the soft member 30 can be easily ensured, and the soft member 30 can also have an ultra-low hardness. The conductive medium can be oriented in the Z direction by, for example, using the force of a magnetic field, an electric field, a flow field, etc., to fix the position of the conductive medium in a state in which the direction and chain arrangement of the conductive medium are determined.

[0072] The soft member 30 can be made of a material that has high electrical conductivity and light transmissivity in the Z direction and low electrical conductivity and light transmissivity in the XY direction, that is, a material that has anisotropy in electrical conductivity and light transmissivity. 8It is preferable that the soft member 30 has a volume resistivity of Ω·cm or more. Since the soft member 30 has a relatively low conductivity in the XY directions, the capacitance sensor is less likely to erroneously detect a touch operation on an operation area 21 other than the operation area 21 paired with the sensor electrode 42. It is preferable that the soft member 30 has a visible light transmittance of, for example, less than 3% in the XY directions. Since the soft member 30 has a relatively low translucency in the XY directions, it is less likely that the non-target operation area 21 will be illuminated, and only the target operation area 21 can be illuminated brightly and prominently.

[0073] The soft member 30 may be configured such that a conductive soft member having a conductive portion 31 and an insulating soft member not having a conductive portion 31 are laminated in the Z direction. In this case, the conductive soft member and the insulating soft member may be laminated alternately, or either one may be laminated continuously.

[0074] Furthermore, the operation switch 10 can include a configuration for holding the top sheet 20, the soft member 30, etc. The operation switch 10 can be configured to have a first hard support member 51 on the surface of the sensor sheet 40 opposite to the surface on which the soft member 30 is arranged. The first hard support member 51 has a thickness (plate thickness) in the Z direction and is in the shape of a thin plate (sheet) having a surface along the XY plane. The first hard support member 51 has a rigidity capable of supporting the soft member 30 and the sensor sheet 40 that tend to be displaced downward in the Z direction.

[0075] In this way, the first hard support member 51 supports the soft member 30 via the sensor sheet 40. Therefore, the first hard support member 51 can maintain the shape of the flexible soft member 30 and the thin and easily deformed sensor sheet 40 and prevent them from flowing out. Furthermore, when the operation area 21 is pressed, the first hard support member 51 generates a repulsive force against compressive deformation in the soft member 30, and appropriately suppresses sinking of the soft member 30 and the sensor sheet 40, thereby maintaining the desired soft tactile sensation.

[0076] First modified example (Figure 5)

[0077] Furthermore, as shown in FIG. 5, the operation switch 10A can be configured to have a second hard support member 52 having a hole between the top sheet 20 and the sensor sheet 40, and the soft member 30 is arranged in the hole. The second hard support member 52 has a thickness (plate thickness) in the Z direction and is in the shape of a thin plate (sheet) having a surface along the XY plane. The second hard support member 52 has a hole penetrating along the Z direction at a position corresponding to the sensor electrode 42. That is, the operation switch 10A here is arranged such that the soft members 30 are individually arranged on the sensor electrodes 42 and are surrounded by the frame-shaped second hard support member 52. As a result, the soft member 30 is arranged only between the operation area 21 and the sensor sheet 40.

[0078] In this manner, the second hard support member 52 surrounds the soft member 30 disposed in the hole. Therefore, the second hard support member 52 can position the soft member 30 from the side. Furthermore, the second hard support member 52 can provide a soft tactile sensation in the operation area 21 and a hard tactile sensation in the peripheral area 22 around the operation area 21. Therefore, according to one embodiment of the present disclosure, the user can perform an input operation at the correct position even without visually checking the operation switch 10A.

[0079] Second Modification (Figure 6)

[0080] Furthermore, as shown in FIG. 6, the operation switch 10B can be configured to have a third hard support member 53 on the surface facing the soft member 30 in the peripheral region 22 of the top sheet 20, for example. The third hard support member 53 has a thickness (plate thickness) in the Z direction and is in the form of a thin plate (sheet) having a surface along the XY plane. The third hard support member 53 has a hole penetrating along the Z direction at a position corresponding to the operation region 21. That is, the operation switch 10B here is configured such that the peripheral region 22 of the top sheet 20 and the third hard support member 53 are laminated. As a result, the peripheral region 22 is larger than the operation region 21. A member harder than the soft member 30 It is thicker in the Z direction.

[0081] In this manner, the third rigid support member 53 is Hard materials in By increasing the thickness of the third hard support member 53, the peripheral region 22 is hardened. Therefore, the third hard support member 53 can provide a soft tactile sensation in the operation region 21 and a hard tactile sensation in the peripheral region 22 around the operation region 21. Therefore, according to one embodiment of the present disclosure, the user can perform an input operation at the correct position even without visually checking the operation switch 10B. It is preferable that the third hard support member 53 has a thickness of, for example, 0.5 mm, since the peripheral region 22 can be hardened.

[0082] The first hard support member 51 and the second hard support member 52 can be made of a hard thermoplastic resin, a hard thermosetting resin, synthetic rubber, a thermoplastic elastomer, or the like. The material used for the first hard support member 51 and the second hard support member 52 is preferably electrically insulating. In particular, for the first hard support member 51, a light-transmitting material is preferable because it can transmit backlight illumination.

[0083] The first hard support member 51 is made up of a second hard support member 52 and a third hard support member 53. Either It may be combined with.

[0084] Third Modification (Figs. 7-8)

[0085] As shown in FIG. 7 and FIG. 8, the operation switch 10C according to the third modification can be configured to have an insulating groove 37 as an "insulating portion" that prevents erroneous detection between adjacent operation areas 21. The operation area 21 here has a first operation area 21A and a second operation area 21B. Furthermore, 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. The soft member 30 has an insulating groove 37 that forms a gap between a first portion 38A located between the first operation area 21A and the first electrode 42A and a second portion 38B 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 in a side view.

[0086] The first portion 38A located between the first operation area 21A and the first electrode 42A that form a pair in this manner and the second portion 38B located between the second operation area 21B and the second electrode 42B that form another pair are separated by the insulating groove 37. The conductivity between the first portion 38A and the second portion 38B that are separated by the insulating groove 37 is extremely low. Therefore, each sensor electrode 42 can be made less susceptible to influences other than the paired operation area 21. Therefore, according to the configuration in which the soft member 30 has the insulating groove 37, the sensitivity and detection accuracy of the sensor of the operation switch 10C can be improved, and erroneous detection can be prevented when the operation switch 10C has a plurality of operation areas 21.

[0087] Furthermore, the insulating groove 37 makes it difficult for light to transmit between the first portion 38A and the second portion 38B. Therefore, light that enters the soft member 30 from the vicinity of the sensor electrode 42 easily reaches the operation area 21 that forms a pair with the sensor electrode 42. Therefore, according to a configuration in which the soft member 30 has the insulating groove 37, it is possible to intensively illuminate the operation area 21 that forms a pair with the sensor electrode 42. Furthermore, when a plurality of pairs of the operation area 21 and the sensor electrode 42 are provided side by side, it is possible to prevent the sensor electrode 42 from illuminating an operation area 21 other than the operation area 21 that is paired with the sensor electrode 42.

[0088] The insulating groove 37 as an "insulating portion" separating the first portion 38A and the second portion 38B is not limited to a gap, and can be made of a material different from the soft member 30. The "insulating portion" can be made of an electrically insulating gel, rubber, resin, or the like. The "insulating portion" made of such a material can also make each sensor electrode 42 less susceptible to influences other than the operation area 21 with which it is paired. Therefore, the sensitivity and detection accuracy of the sensor of the operation switch 10C can be improved, and erroneous detection can be prevented when the operation switch 10C has multiple operation areas 21. Similarly, the "insulating portion" made of an electrically insulating gel, rubber, resin, or the like can also intensively illuminate the operation area 21 that is paired with the sensor electrode 42. Furthermore, when multiple pairs of the operation area 21 and the sensor electrode 42 are arranged side by side, it can be prevented that the sensor electrode 42 illuminates an operation area 21 other than the operation area 21 with which it is paired.

[0089] Second embodiment (Figs. 9 to 13)

[0090] Operation switch 10 as a "capacitive input device" , 10A, 10B and 10C The sensor sheet 40 in this embodiment is not limited to being embedded under a flat surface sheet 20 without any irregularities, but may also be applied to an electronic device having an input unit with a three-dimensional outer surface. That is, the operation switch 10D of this embodiment has a three-dimensional outer surface, and the operation area 21 is formed on the outer surface. As shown in Figs. 9 and 10, the surface sheet 20 has a cylindrical three-dimensional surface. The operation area 21 is provided on the top surface of the cylindrical surface. The sensor sheet 40 in this embodiment is arranged upside down from the first embodiment. That is, the sensor sheet 40 is arranged such that the base sheet 41 faces the soft member 30. A disk-shaped first hard support member 51 is provided on the surface of the sensor sheet 40 opposite to the surface facing the soft member 30.

[0091] In this manner, in this embodiment, the operation area 21 is formed on the outer surface of a three-dimensional shape. Therefore, this embodiment can expand the range of application of the operation switch 10. The three-dimensional shape in which the operation area 21 is provided is not limited to a cylindrical shape, and the operation area 21 can be provided in various three-dimensional shapes, such as a convex surface, a concave surface, a prism shape, a truncated cone shape, a truncated pyramid shape, and a ring shape.

[0092] Fourth Modification (Figs. 11 to 13)

[0093] The outer surface on which the operation area 21 is formed is not limited to the top surface of the three-dimensional shape. In an operation switch 10E according to a fourth modified example shown in Figs. 11 and 12, the 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 intervals of 90° in the circumferential direction. A base sheet 41 is provided concentrically with the top sheet 20 on the radial inner side of the operation area 21. Sensor electrodes 42 are provided on the inner peripheral surface of the base sheet 41 at positions radially corresponding to the respective operation areas 21. A soft member 30 is provided between the top sheet 20 and the base sheet 41.

[0094] The soft members 30 may be arranged continuously in a cylindrical shape as shown in Fig. 13A. On the other hand, the soft members 30 may be provided at four locations at 90° intervals in the circumferential direction corresponding to the operation area 21 and the sensor electrodes 42 as shown in Fig. 13B. In this case, a frame-shaped fourth hard support member 54 is provided between adjacent soft members 30.

[0095] In this manner, in this embodiment, the operation area 21 is formed on the side surface (outer peripheral surface) of the three-dimensional shape. Like From the top Downwards An input device for electronic equipment that is operated by pressing in a direction crossing the direction of the arrow This disclosure The scope of application can be expanded.

[0096] The sensor sheet 40 here is arranged upside down compared to the first embodiment. That is, the sensor sheet 40 is arranged so that the base sheet 41 faces the soft member 30. However, the sensor sheet 40 of this embodiment may be arranged in the same direction as the first embodiment.

[0097] Third embodiment (Figs. 14 to 17)

[0098] The "capacitive input device" can also be configured so that the surface sheet 20 widely covers the outer surface of the electronic device so that the surface is continuously connected to the surrounding exterior member 60 (housing). That is, as shown in Fig. 14 etc., the surface sheet 20 of this embodiment continuously covers all the surfaces of the operation switches 10 (operation switches 10F and 10H are shown) arranged side by side and the exterior member 60, forming the outer surface of the electronic device.

[0099] The operation switch 10F according to the third embodiment shown in FIG. 15 is arranged so that the edge of the exterior member 60 protrudes from the outer surface of the exterior member 60 via a small gap. The sensor electrode 42 is omitted from the illustration. The operation switch 10F is configured so that the top surface of the protruding top sheet 20 is the operation area 21 as a whole. The soft member 30 is disc-shaped. The soft member 30 is supported by the top surface of the fifth hard support member 55 so that the soft member 30 is entirely arranged on the back side of the top sheet 20 in the area of ​​the operation switch 10F. The sensor sheet 40 is provided on the surface of the fifth hard support member 55 opposite to the arrangement surface of the soft member 30. Alternatively, the sensor sheet 40 may be provided between the fifth hard support member 55 and the soft member 30.

[0100] Fifth Modification (Figure 16)

[0101] The soft member 30 of the operation switch 10G according to the fifth modified example shown in Fig. 16 has a hollow cylindrical shape. The top sheet 20 is directly supported by a fifth hard support member 55. The soft member 30 is supported by the outer peripheral surface of the fifth hard support member 55 so as to be entirely disposed on the inner peripheral side of the side surface of the top sheet 20.

[0102] Sixth Modification (Figure 17)

[0103] The operation switch 10H according to the sixth modified example shown in FIG. 17 is arranged so that the edge of the exterior member 60 does not protrude from the outer surface of the exterior member 60 with a small gap. That is, the top sheet 20 is arranged so as to be flat in both the areas of the operation switch 10H and the exterior member 60. The soft member 30 has a rectangular flat plate shape. The soft member 30 is supported by the top surface of the sixth hard support member 56 so as to be entirely arranged on the back side of the top sheet 20 in the area of ​​the operation switch 10H. The sensor sheet 40 is provided on the surface of the sixth hard support member 56 opposite to the arrangement surface of the soft member 30. Alternatively, the sensor sheet 40 may be provided between the sixth hard support member 56 and the soft member 30.

[0104] In the operation switch 10F etc. of this 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 this embodiment, it is possible to achieve a seamless appearance with no gaps or joints between the members on the surface.

[0105] If the top sheet 20 is soft or sufficiently thin, the top sheet 20 in the gap between the operation switch 10F etc. and the exterior member 60 can be stretched or bent, so that the operation area 21 of the operation switch 10F etc. can be pressed against the exterior member 60 to operate it. However, the top sheet 20 in the area adjacent to the soft member 30 The soft member 30 Since the tactile sensation can be obtained by crushing the operation area 21, the top sheet 20 does not have to be configured to deform relative to the exterior member 60 when the operation area 21 is pressed.

[0106] In the "capacitive input device" disclosed in this application, the configurations shown in the respective embodiments and modifications can be freely combined within a range that does not cause contradictions. For example, the second hard support member 52, the third hard support member 53, etc. in the first embodiment may be combined with the configuration of the second embodiment.

[0107] Although each embodiment has been described in detail above, it will be readily apparent to those skilled in the art that many modifications are possible without substantially departing from the novel features and effects of the present invention. Accordingly, all such modifications are intended to be included within the scope of the present invention. EXAMPLES

[0108] The operation switch 10 and the like as the "capacitive input device" in this embodiment will be described in more detail and specifically below with reference to examples. However, this embodiment is not limited to the following examples.

[0109] The example used is an operation switch 10 in which a surface sheet 20, a sensor sheet 40, and a soft member 30 are arranged between them, as shown in FIG. 3 and the like. A soft polyurethane sheet having a thickness of 0.05 mm was used for the surface sheet 20. The sensor sheet 40 was used in which a plurality of (two or more) sensor electrodes 42 and circuit wiring formed on a base sheet 41 were covered with a protective layer 43. A PET sheet having a thickness of 0.1 mm was used as the base sheet 41. The plurality of sensor electrodes 42 were conductive coatings formed using a PEDOT / PSS conductive paste. Furthermore, the circuit wiring was a conductive coating formed using a paste containing silver powder. An electrically insulating resin coating was formed as the protective layer 43.

[0110] As the soft member 30, for each of the configuration examples shown in Table 1, One The soft member 30 used here is made of a material or a combination of materials made of different materials. AdjacentThe soft member 30 was provided so as to straddle and cover the two sensor electrodes 42. The overall thickness of the soft member 30 was adjusted to be 3 mm in total.

[0111] The volume resistivity [Ω·cm] in the thickness direction (Z direction) and surface direction (XY direction) of each prepared soft member 30 was measured. The volume resistivity was calculated by measuring the electrical resistance value [Ω] in the thickness direction and surface direction of the soft member 30, multiplying it by the cross-sectional area and dividing it by the length. A digital multimeter (R6552 manufactured by ADVANTEST Co., Ltd.) was used to measure the electrical resistance value. When measuring the electrical resistance value of a member having a thickness of 1.0 mm such as in Configuration Example 2 described later, five sheets were stacked in the thickness direction so that the total thickness was 0.5 cm, and then the electrical resistance value was measured.

[0112] Each of the obtained operation switches 10 was placed on a measurement table S as shown in Fig. 18 and various measurements were performed. For each operation switch 10, a pusher P imitating a human finger I as an "operation body" was used as a measuring element. each The sensor electrode 42 was pressed from above against its center, and the repulsive load [N] relative to the pressing distance (stroke) [mm] and the sensor sensitivity of each sensor electrode 42 were measured. The pusher P was made of conductive rubber with a hardness of A60, and had a cylindrical shape with a diameter of 6 mm. The repulsive load was detected by a load cell connected to the pusher P having the conductive rubber at its tip.

[0113] In this embodiment, a wide variety of materials are used for the soft member 30. For this reason, the pressing distance for each soft member 30 is 1.0 mm, and the repulsive load at the time when the soft member 30 is compressed by 33% is defined as a unified index of hardness in this embodiment. It has been confirmed in advance that if the repulsive load at the time of 33% compression is 6N or less, the material is soft to the touch at a low load and is preferable as the material for the soft member 30.

[0114] The sensor sensitivity of each sensor electrode 42 was measured by connecting the terminal of the sensor sheet 40 that was electrically connected to the sensor electrode 42 to a control IC (Integrated Circuit). A PSoC (registered trademark) IC (a microcontroller CY8C24894 56-pin QFN (Quad Flat Non-leaded package) manufactured by Cypress Semiconductor Corp.) was used as the control IC. The parameters of the PSoC IC were set to Resolution of 12 bits (4096), Ref Value of 2, Prescaler Period of 3, Scanning Speed ​​of Normal, and PRS Polynomial (pseudo random sequence polynomial) of Short.

[0115] A DIFF value [-] based on the amount of change in capacitance was used as an index showing the sensor sensitivity of each sensor electrode 42. Here, the DIFF value is the difference between the detected capacitance value (RAW value) and the baseline value (DIFF value = actual measurement 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 another sensor electrode 42 adjacent to the sensor electrode 42 to be operated were measured.

[0116] (Configuration example 1)

[0117] In the configuration example 1, a non-conductive gel was used as an insulating soft member for the soft member 30. A two-component addition reaction type silicone gel (TSE3070 manufactured by Momentive Corp.) was used as the non-conductive gel. The soft member 30 in the configuration example 1 had a volume resistivity of 1×10 15 It was an insulating silicone gel with electrical insulation of Ω·cm, and the volume resistivity in the thickness direction and surface direction could be considered to be approximately the same. Furthermore, this silicone gel had a low hardness with a penetration of 65 after curing. This silicone gel was also colorless and transparent, and had good light transmittance.

[0118] (Configuration example 2)

[0119] In the configuration example 2, a conductive gel was used as the conductive soft member for the soft member 30. For the conductive gel, an adhesive pad for a low-frequency treatment device (HV-PAD-3 manufactured by Omron Healthcare Co., Ltd.) using a conductive hydrogel was used. In this hydrogel, a nonwoven fabric was used as an intermediate substrate. The electrical resistance value of the soft member 30 in the configuration example 2 was 3×10 5 Ω, volume resistivity is 6×10 5 The volume resistivity in the thickness direction and the surface direction was approximately the same, and the hydrogel had good light transmittance. The soft member 30 in the configuration example 2 was arranged by stacking three sheets of the same type of sheet-shaped adhesive pads each having a thickness of 1.0 mm. Therefore, the overall thickness of the soft member 30 was 3 mm.

[0120] (Configuration example 3)

[0121] In configuration example 3, the non-conductive gel of configuration example 1 and the conductive gel of configuration example 2 were combined and used as the soft member 30. Here, a laminated soft member 30 was used in which the conductive gel was arranged in the upper layer on the side of the top sheet 20 and the non-conductive gel was arranged in the lower layer on the side of the sensor electrode 42. The silicone gel was formed to a thickness of 2 mm, and a hydrogel having a thickness of 1.0 mm was laminated on top of it, so that the overall thickness of the soft member 30 in configuration example 3 was 3 mm. The soft member 30 in configuration example 3 has a volume resistivity of 1×10 15 The volume resistivity in the thickness direction and in the surface direction of the lower layer where the non-conductive gel is disposed can be considered to be substantially the same. Since the volume resistivity in the lower layer of the soft member 30 is high in this way, the effect of the sensitivity on the adjacent sensor electrode 42 is small.

[0122] (Configuration Example 4)

[0123] In configuration example 4, an anisotropic conductive gel was used as the soft member 30, which was made by mixing a conductive medium with an insulating (non-conductor) base material and then orienting the conductive medium in the thickness direction of the soft member 30, thereby imparting higher conductivity in the thickness direction than in the surface direction of the soft member 30. The base material of the anisotropic conductive gel was a two-component addition reaction type silicone gel (TSE3070 manufactured by Momentive Corp.) similar to that of configuration example 1 described above. The conductive filler, which is a substance that imparts conductivity, was a silver-plated nickel powder with an average particle size of 30 μm formed by plating silver on a nickel base material.

[0124] The soft member 30 in Configuration Example 4 was formed by blending silver-plated nickel powder into an insulating silicone gel, applying a magnetic field in a certain direction, and then cross-linking and curing the mixture. In this way, an anisotropic conductive silicone gel sheet having an orientation portion 32 in which silver-plated nickel particles are continuously aligned in the thickness direction of a sheet having a thickness of 3 mm was obtained as the soft member 30 in Configuration Example 4. The soft member 30 in Configuration Example 4 had a volume resistivity in the thickness direction of 1.5×10 -1 Ω cm, and the volume resistivity in the plane direction is 1×10 8 The value was Ω·cm.

[0125] (Configuration Example 5)

[0126] In the configuration example 5, insulating rubber, which is an insulator (non-conductor), was used as the soft member 30. The insulating rubber used was a two-component liquid silicone rubber (KE-1950-10A / B manufactured by Shin-Etsu Chemical Co., Ltd.) cured by an addition reaction. The soft member 30 in the configuration example 5 had a volume resistivity of 1×10 15 The insulating silicone rubber has an electrical insulation property of Ω·cm, and the volume resistivity in the thickness direction and the surface direction can be considered to be substantially the same. Furthermore, this silicone rubber has a hardness of A10, which is a low hardness. The thickness of the soft member 30 in the configuration example 5 was adjusted to be 3 mm.

[0127] (Comparative Example)

[0128] In the comparative example, insulating rubber of an insulator (non-conductor) was used as a member corresponding to the soft member 30. The insulating rubber was made by hardening a two-component liquid silicone rubber (KE-1950-20A / B manufactured by Shin-Etsu Chemical Co., Ltd.) by addition reaction. In the comparative example, the hardness of the member corresponding to the soft member 30 in the above-mentioned configuration example 5 was A20. The rest was the same as the above-mentioned configuration example 5.

[0129] [Table 1]

[0130] Rebound load and DIFF value

[0131] (Configuration example 1)

[0132] In the configuration example 1, the repulsive load for the pressing operation remained at a low value. That is, even when the pressing distance in the configuration example 1 reached 1.0 mm (33% compression), the repulsive load in the configuration example 1 was only 0.1 N, which was significantly lower than 6 N, and the low load state was maintained. Therefore, it was found that the configuration example 1 provided a soft pressing operation feeling.

[0133] On the other hand, in the configuration example 1, the DIFF value suddenly became a high value when the pressing distance exceeded a predetermined amount. That is, the DIFF value in the configuration example 1 was 57.4 when the pressing distance was 0.2 mm, and did not reach 100 even when the pressing distance became 0.5 mm, whereas it became 447 when the pressing distance became 1.0 mm. Furthermore, although the DIFF value was at a lower level compared to the sensor electrode 42 to be operated, the DIFF value was also detected in the other adjacent sensor electrodes 42. However, this is possible by setting a threshold value such as a DIFF value of 100 or 40% of the maximum DIFF value, so that only the operation on the desired sensor electrode 42 can be detected.

[0134] From the above results, it was found that configuration example 1 provides an operation switch 10 that has a soft feel when initially pressed and detects the operation when pressed to a certain extent, and has good pressure sensitivity characteristics.

[0135] (Configuration example 2)

[0136] In Configuration Example 2, the repulsive load increased in value in a sensitive response to the pressing distance. That is, the repulsive load in Configuration Example 2 was 0.2 N when the pressing distance was 0.2 mm, and was 1.8 N when the pressing distance was 1.0 mm (33% compression). It was presumed that the reason the repulsive load of Configuration Example 2 was higher than that of Configuration Example 1 was due to the influence of the nonwoven fabric contained in the soft member 30. However, the repulsive load of Configuration Example 2 when the soft member 30 was compressed 33% was significantly lower than 6 N. Therefore, it was found that Configuration Example 2 maintained a low repulsive load against the pressing operation, and had a soft and pleasant feel.

[0137] On the other hand, in the configuration example 2, the DIFF value also became high in response to the pressing distance. That is, the DIFF value in the configuration example 2 was already 95 when the pressing distance was 0.2 mm, and became 440 when the pressing distance became 1.0 mm. Therefore, it was found that the pressing operation can be detected even with a small pressing distance according to the configuration example 2. Furthermore, in the configuration example 2, the DIFF value was hardly detected in other adjacent sensor electrodes 42.

[0138] From the above results, it was found that configuration example 2 enables highly reliable detection in which an operation is detected only in a narrow range corresponding to a desired sensor electrode 42, that is, only at the pressed location, and not at other adjacent sensor electrodes 42. It was also found that this high reliability can be achieved even in a range where the pressing distance is small.

[0139] (Configuration example 3)

[0140] In configuration example 3, the repulsive load remained at a lower value than in configuration example 2. That is, the repulsive load in configuration example 3 was 0.04 N when the pushing distance was 0.2 mm, and was 0.5 N even when the pushing distance was 1.0 mm, which was significantly below 6 N. Therefore, it was found that configuration example 3 can reduce the repulsive load and provide a soft pushing operation feeling.

[0141] On the other hand, in the configuration example 3, the DIFF value became high in response to the pressing distance. That is, the DIFF value in the configuration example 3 was already 210 when the pressing distance was 0.2 mm, and became 503 when the pressing distance became 1.0 mm. Therefore, it was found that the pressing operation can be detected even with a small pressing distance according to the configuration example 3. Furthermore, in the configuration example 3, the DIFF value of the other adjacent sensor electrodes 42 was maintained at 100 or less.

[0142] From the above results, in configuration example 3, the repulsive load against the pressing operation could be reduced compared to configuration example 2 in which a conductive gel was used for the soft member 30. Furthermore, in configuration example 3, the DIFF value was high even at the beginning of pressing when the pressing distance was small compared to configuration example 1 in which a non-conductive gel was used for the soft member 30, and it was found that the pressing operation could be detected. Therefore, according to configuration example 3, it was shown that the repulsive load against the pressing operation and the sensor sensitivity (DIFF value) can be adjusted by the combination of members laminated on the soft member 30, even without adjusting the composition of the conductive medium in the conductive gel as in configuration example 2, for example.

[0143] (Configuration Example 4)

[0144] In Configuration Example 4, the repulsive load was higher than that in Configuration Example 1. That is, the repulsive load in Configuration Example 4 was 3.4 N when the pushing distance was 1.0 mm (33% compression). It was presumed that the conductive medium contained in the soft member 30 influenced the repulsive load in Configuration Example 4, which was higher than that in Configuration Example 1. However, the repulsive load in Configuration Example 4 when the soft member 30 was compressed 33% was significantly lower than 6 N. Therefore, it was found that Configuration Example 4 maintained the repulsion against the pushing operation at a low load, and had a soft and pleasant feel.

[0145] On the other hand, in configuration example 4, the DIFF value became high in response to the pressing distance. That is, the DIFF value in configuration example 4 was already 291 when the pressing distance was 0.2 mm, and became 525 when the pressing distance became 1.0 mm. Therefore, it was found that configuration example 4 can detect a pressing operation even with a small pressing distance. Furthermore, in configuration example 4, the DIFF value was hardly detected in other adjacent sensor electrodes 42.

[0146] From the above results, in the configuration example 4, since the soft member 30 has anisotropic conductivity, it was found that the sensor sensitivity of the sensor electrode 42 located in the thickness direction of the soft member 30, in which the orientation portion 32 is elongated and has a low volume resistivity, is high with respect to the operation area 21 where the pressing operation was performed. On the other hand, in the configuration example 4, it was found that the sensor sensitivity of other sensor electrodes 42 adjacent to the sensor electrode 42 to be operated is extremely low. Therefore, it was found that the configuration example 4 is capable of more reliable detection, in that the operation is detected only in a narrow range corresponding to the desired sensor electrode 42, that is, at the pressed location, and not detected by other adjacent sensor electrodes 42. It was also found that this high reliability is realized even in a range where the pressing distance is small.

[0147] (Configuration Example 5)

[0148] In configuration example 5, the repulsive load was higher than the other configuration examples. That is, the repulsive load in configuration example 5 was 5.2 N when the pushing distance was 1.0 mm (33% compression). However, the repulsive load when the soft member 30 in configuration example 5 was compressed by 33% was 6 N or less. Therefore, it was found that according to configuration example 5, the repulsion against the pushing operation was maintained at a low load, and the touch was soft and pleasant.

[0149] On the other hand, in the configuration example 5, the DIFF value suddenly became a high value when the pressing distance exceeded a predetermined amount. That is, the DIFF value in the configuration example 5 was 65.6 when the pressing distance was 0.2 mm, but became 447 when the pressing distance became 1.0 mm. Furthermore, although the DIFF value was at a lower level compared to the sensor electrode 42 to be operated, the DIFF value was also detected in the other adjacent sensor electrodes 42. However, this can be achieved by setting a threshold value such as a DIFF value of 100 or 40% of the maximum DIFF value, so that only the operation on the desired sensor electrode 42 can be detected.

[0150] From the above results, it was found that in configuration example 5, the repulsive load against the pressing operation was low, the tactile sensation was soft, and the pressing operation could be reliably detected by setting an appropriate threshold value for the DIFF value.

[0151] (Comparative Example)

[0152] In the comparative example, the repulsive load was higher than those of the other configuration examples. That is, the repulsive load in the comparative example was 9.3 N when the pushing distance was 1.0 mm (33% compression). Therefore, the soft member 30 in the comparative example Equivalent parts The repulsive load at 33% compression did not become 6 N or less. Therefore, in the comparative example, the repulsive load against the pressing operation was not maintained at a low load state, and the tactile sensation could not be made soft.

[0153] The following findings were obtained from the above examples.

[0154] From the results of configuration examples 2 and 4, it was confirmed that when a conductive gel was used as the soft member 30, the sensor sensitivity of the sensor electrode 42 corresponding to the operation area 21 increased, and conversely, the effect on other sensor electrodes 42 adjacent to the sensor electrode 42 to be operated was small. Furthermore, from the results of configuration example 4, it was confirmed that when a conductive gel having anisotropy with higher conductivity in the thickness direction compared to the surface direction was used as the soft member 30, this tendency became even stronger, and only the sensor electrode 42 corresponding to the operation area 21 reacted.

[0155] On the other hand, from the results of Configuration Example 1, Configuration Example 3, and Configuration Example 5, it was confirmed that when a non-conductive material is present in the layer configuration of the soft member 30, other sensor electrodes 42 adjacent to the sensor electrode 42 to be operated may react simultaneously. And, from the results of Configuration Example 1, it was found that when a non-conductive gel is used as the soft member 30, the sensor sensitivity does not increase in the low repulsive load range, making detection difficult, and further, there is an increased tendency for other adjacent sensor electrodes 42 to react simultaneously. [Explanation of symbols]

[0156] 1. Automobiles 2 Driver's seat 3 Passenger seat 4. Steering 5. Centre console 6 Center Cluster 7 Door armrest area 10 Operation switch (capacitive input device) 10A Operation switch (first modified example) (capacitive input device) 10B Operation switch (second modified example) (capacitive input device) 10C Operation switch (third modified example) (capacitive input device) 10D Operation switch (second embodiment) (capacitive input device) 10E Operation switch (fourth modified example) (capacitive input device) 10F Operation switch (third embodiment) (capacitive input device) 10G Operation switch (Fifth variant) (capacitive input device) 10H Operation switch (sixth variant) (capacitive input device) 20 Surface sheet (surface material) 21 Operation area 21A First Operation Area 21B Second Operation Area 22 Surrounding Areas 30 Soft materials 31 Conductive part 32 Orientation section 33 Spherical particles 34 Fiber-shaped particles 35 Long fiber shaped particles 36 Fiber-shaped particles 37 Insulation groove (insulation part) 38A First Part 38B Second Part 40 Sensor sheet 41 Base sheet 42 Sensor electrode 42A First Electrode 42B Second electrode 43 Protective layer 51 First rigid support member 52 Second rigid support member 53 Third rigid support member 54 Fourth rigid support member 55 Fifth rigid support member 56 Sixth rigid support member 60 Exterior materials I finger (operating object) P pusher S measuring stand X Left / right direction Y Front-rear direction Z Height direction, up and down direction

Claims

1. A surface member, A soft member; a sensor sheet for detecting a change in capacitance; the surface member has an operation area for 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 pressed 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. the soft member has a conductive portion therein, the conductive portion increases a value of the capacitance in order to increase detection sensitivity in a portion between the operation area and the sensor electrode; the conductive portion is a conductive medium contained in the soft member made of a polymer matrix, The conductive portion is an orientation portion in which the conductive medium is oriented in the soft member. Capacitive input device.

2. The orientation portion orients the conductive medium so that the conductive medium is chained in the thickness direction of the soft member.

2. The capacitive input device according to claim 1.

3. The orientation portion is such that the conductive medium is discontinuously oriented, When the operation area is pressed by a touch operation, the conductive media come into contact with each other and are electrically connected.

2. The capacitive input device according to claim 1.

4. A surface member, A soft member; a sensor sheet for detecting a change in capacitance; the surface member has an operation area for 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 pressed 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. The soft member is a gel-like polymer matrix. Capacitive input device.

5. A surface member, A soft member; a sensor sheet for detecting a change in capacitance; the surface member has an operation area for 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 pressed 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. The soft member has a plate shape having a plate thickness in a thickness direction of the soft member and a surface along a plane in a direction intersecting the thickness direction. Capacitive input device.

6. A surface member, A soft member; a sensor sheet for detecting a change in capacitance; the surface member has an operation area for 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 pressed 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. Furthermore, the capacitive input device has a resin film, which is either an elastic urethane film or a thin film, on the soft member side of the surface member to prevent the soft member from penetrating into the surface member. Capacitive input device.

7. The soft member is formed of a light-transmitting material that allows the operation area to be illuminated.

7. The capacitance type input device according to claim 1, wherein the capacitance type input device is a capacitance type input device having a capacitance of 1 to 6.

8. The operation area includes a first operation area and a second operation area, the sensor electrode has 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 located between the first operation area and the first electrode and a second portion located between the second operation area and the second electrode.

8. The capacitive input device according to claim 1, wherein the capacitance is a distance from the input terminal to the input terminal.

9. The sensor sheet further includes a first hard support member on a surface opposite to the surface on which the soft member is disposed.

9. The capacitance type input device according to claim 1, wherein the capacitance type input device is a capacitance type input device having a capacitance of 1 to 8.

10. a second rigid support member having an aperture between the surface member and the sensor sheet; The soft member is disposed in the hole.

10. The capacitance type input device according to claim 1.

11. The capacitive input device further includes a second hard support member between the surface member and the sensor sheet, The soft member is disposed such that the periphery of the soft member is surrounded by the frame-shaped second hard support member so as to be positioned from the side of the soft member.

10. The capacitance type input device according to claim 1.

12. having a three-dimensional outer surface, The operation area is formed on the outer surface.

12. The capacitance type input device according to claim 1.

13. The soft member is formed by laminating a plurality of members.

13. The capacitive input device according to claim 1.

14. The plurality of members are a combination of insulating soft members and conductive soft members.

14. The capacitive input device according to claim 13.

15. The soft member has a thickness of 1 mm to 5 mm.

15. The capacitive input device according to claim 1.

16. Furthermore, the capacitive input device has a third hard support member on a surface of the surface member facing the soft member in a peripheral area of ​​the operation area.

16. The capacitance type input device according to claim 1.

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