Touch sensor

Abstract

A touch sensor (1) comprises: a sheet (3); a first electrode (reception electrode (12)); a second electrode (30A); and a buffer (41A) formed from a plurality of unit structures (42). The second electrode (30A) has a plurality of first thin lines (31) and a plurality of second thin lines (32). The unit structures (42) each have: a third thin line (43) that is positioned on the same straight line as one of the plurality of first thin lines (31) and extends along a first direction (D1); and a fourth thin line (44) that is positioned on the same straight line as one of the plurality of second thin lines (32) and extends along a second direction (D2).

Description

Touch Sensor

[0001] The present invention relates to a touch sensor.

[0002] 2. Description of the Related Art Conventionally, for example, techniques relating to capacitive touch sensors are known, such as those disclosed in Patent Documents 1 and 2.

[0003] Figures 29 and 30 of Patent Document 1 disclose a touch sensor (conductive sheet 1 for touch panel) that includes a base 30, a plurality of second conductive patterns 42 formed on the base 30, and a plurality of second non-conductive patterns 58 that are not energized.

[0004] In Patent Document 1, the multiple second conductive patterns 42 are arranged at intervals from one another in a direction (left-right direction on the paper surface of FIG. 29 ) perpendicular to the extension direction of each second conductive pattern 42. Each second non-conductive pattern 58 is arranged between the second conductive patterns 42, 42 in the direction perpendicular to the extension direction of each second conductive pattern 42.

[0005] Furthermore, in Patent Document 1, each of the second conductive pattern 42 and the second non-conductive pattern 58 is composed of a plurality of thin metal wires. In the adjacent second conductive pattern 42 and second non-conductive pattern 58, a disconnection is provided between the thin metal wires constituting the second conductive pattern 42 and the thin metal wires constituting the second non-conductive pattern 58. This disconnection electrically insulates the second non-conductive pattern 58 from the second conductive pattern 42.

[0006] 2, 9, and 15 of Patent Document 2 disclose a touch sensor (conductive sheet 10 for touch panels) including a transparent insulating substrate 30, a plurality of second electrodes 42 formed on the transparent insulating substrate 30, a plurality of first dummy lines 53 that are not energized, and a plurality of first unconnected lines 50 that are not energized. Each second electrode 42 includes a plurality of first electrode lines 35 (a plurality of thin metal wires).

[0007] In Patent Document 2, the second electrodes 42 are spaced apart from one another in a direction (left-right direction on the paper surface of FIG. 2 ) perpendicular to the extension direction of each second electrode 42. The first dummy lines 53 are arranged between the second electrodes 42, 42 in a direction perpendicular to the extension direction of each second electrode 42.

[0008] Furthermore, in Patent Document 2, each second electrode 42 includes a plurality of first electrode wires 35 (a plurality of thin metal wires). A disconnection is provided between each first electrode wire 35 of the second electrode 42 and each first dummy line 53 adjacent to each first electrode wire 35. Due to this disconnection, the plurality of first dummy lines 53 are electrically insulated from the plurality of first electrode wires 35.

[0009] Furthermore, in Patent Document 2, the multiple first unconnected lines 50 are arranged within a diamond-shaped grid formed by the first electrode wires 35 so as to divide the diamond-shaped grid by congruent diamonds. The end of each first unconnected line 50 is arranged at a distance from the middle of the first electrode wires 35 that form the diamond-shaped grid. As a result, the multiple first unconnected lines 50 are electrically insulated from the multiple first electrode wires 35.

[0010] JP 2013-149236 A International Publication No. 2018 / 163672

[0011] As described above, in the touch sensor of Patent Document 1, the second non-conductive pattern 58 is configured with a plurality of thin metal wires, similar to the second conductive pattern 42. In other words, the second non-conductive pattern 58 is configured as a so-called dummy pattern that is electrically isolated from the second conductive pattern 42. This dummy pattern makes it possible to prevent a decrease in visibility in the touch sensor.

[0012] However, because the second non-conductive pattern 58 adjacent to the second conductive pattern 42 is configured using a plurality of thin metal wires, it is susceptible to electrical influence from the second conductive pattern 42 when in a conducting state. Specifically, the second non-conductive pattern 58 is susceptible to so-called parasitic capacitance due to the second conductive pattern 42 when in a conducting state. If the parasitic capacitance increases in the second non-conductive pattern 58, the proportion of capacitance in the second conductive pattern 42 that contributes to the sensor characteristics decreases. As a result, a problem may occur in which the sensor function of the second conductive pattern 42 is degraded due to the second non-conductive pattern 58.

[0013] Furthermore, the plurality of first dummy lines 53 disclosed in Patent Document 2 are also likely to generate parasitic capacitance due to the electrical influence of the plurality of first electrode lines 35. As a result, in the touch sensor of Patent Document 2, as in Patent Document 1, a problem may occur in which the sensor function of each second electrode 42 including the plurality of first electrode lines 35 is reduced due to the plurality of first dummy lines 53.

[0014] Furthermore, as described above, in the touch sensor of Patent Document 2, the plurality of first unconnected lines 50 are configured as dummy patterns provided within a diamond-shaped lattice made up of the first electrode lines 35. With this configuration, it is possible to prevent a decrease in visibility in the touch sensor.

[0015] However, like the multiple first dummy lines 53, the multiple first unconnected lines 50 are also susceptible to electrical influence from the multiple first electrode lines 35 when they are in a conducting state. That is, parasitic capacitance is likely to occur in the multiple first unconnected lines 50. When the parasitic capacitance in the multiple first unconnected lines 50 increases, the proportion of capacitance in the multiple first electrode lines 35 that contributes to the characteristics of the touch sensor decreases. As a result, a problem may occur in which the multiple first unconnected lines 50 causes a deterioration in the sensor function of each second electrode 42 including the multiple first electrode lines 35.

[0016] The present disclosure has been made in consideration of the above points, and its purpose is to ensure the visibility of the touch sensor and to suppress degradation of the sensor function.

[0017] To achieve the above object, one embodiment of the present disclosure is a touch sensor comprising: a sheet; a first electrode formed on the sheet; a second electrode provided on the same surface of the sheet as the first electrode, electrically insulated from the first electrode, and not conducting electricity; and a buffer disposed between the first electrode and the second electrode, electrically insulated from both the first electrode and the second electrode, the buffer formed of a plurality of unit structures. The second electrode has a plurality of first thin wires extending in a first direction and a plurality of second thin wires extending in a second direction different from the first direction. The unit structures include a third thin wire positioned in the same line as one of the plurality of first thin wires and extending in the first direction, and a fourth thin wire positioned in the same line as one of the plurality of second thin wires and extending in the second direction.

[0018] According to the present disclosure, it is possible to ensure the visibility of the touch sensor and suppress deterioration of the sensor function.

[0019] FIG. 1 is an overall perspective view of a touch sensor according to a first embodiment of the present disclosure. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1 . FIG. 3 is a partially enlarged view of section III shown in FIG. 2 . FIG. 4 is a perspective view schematically illustrating the touch sensor as viewed from the top. FIG. 5 is a schematic diagram illustrating the transmitting electrodes, first wiring section, and pads as viewed from the bottom of the sheet. FIG. 6 is a schematic diagram illustrating the receiving electrodes, second wiring section, and pads as viewed from the top of the sheet. FIG. 7 is a cross-sectional view schematically illustrating the cross-sectional structure of a thin wire. FIG. 8 is a partially enlarged view of section VIII shown in FIG. 6 . FIG. 9 is a partially enlarged view of section IX shown in FIG. 8 . FIG. 10 is a partially enlarged view of a touch sensor according to a first modification of the first embodiment, corresponding to FIG. 8 . FIG. 11 is a partially enlarged view of section XI shown in FIG. 10 . FIG. 12 is a partially enlarged view of a touch sensor according to a second modification of the first embodiment, corresponding to FIG. 8 . FIG. 13 is a partially enlarged view of a touch sensor according to a second embodiment of the present disclosure, corresponding to FIG. 8 . Fig. 14 is a partially enlarged view showing an arbitrary grid shown in Fig. 13 and a second electrode and a buffer located within the grid. Fig. 15 is a view equivalent to Fig. 14 showing an arbitrary grid, a second electrode and a buffer located within the grid in a touch sensor according to a modification of the second embodiment. Fig. 16 is a view equivalent to Fig. 9 showing an enlarged portion of a touch sensor according to another embodiment of the first embodiment. Fig. 17 is a view equivalent to Fig. 14 showing an enlarged portion of a touch sensor according to another embodiment of the second embodiment. Fig. 18 is a view equivalent to Fig. 9 showing an enlarged portion of a touch sensor according to another embodiment of the first embodiment (particularly, a configuration in which each cell adjacent to the buffer is in a closed state).

[0020] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings. The following description of each embodiment is merely exemplary in nature and is not intended to limit the present disclosure, its applications, or its uses.

[0021] 1 shows an entire touch sensor 1 according to a first embodiment of the present disclosure. The touch sensor 1 is a capacitance-type sensor-type input device. The touch sensor 1 is used as an input device for in-vehicle devices such as car navigation systems, display devices for personal computers, mobile phones, personal digital assistants, portable game machines, copy machines, ticket machines, automated teller machines, watches, and the like.

[0022] In the following description, the side on which an operation surface 2b (see FIGS. 1 and 2) of a cover member 2 (described later) is located will be referred to as the "upper side" of the touch sensor 1, and the opposite side will be referred to as the "lower side" of the touch sensor 1, and the positional relationship of the elements constituting the touch sensor 1 will be defined accordingly. Note that this positional relationship is unrelated to the orientation of the touch sensor 1 or a product to which the touch sensor 1 is applied during actual use.

[0023] Furthermore, in the first embodiment of the present disclosure, for convenience of explanation, the direction from the lower left side of the paper in FIG. 8 to the diagonally upper right side of the paper (direction D1 shown in FIG. 8) is defined as the "first direction." The direction from the upper left side of the paper in FIG. 8 to the diagonally lower right side of the paper (direction D2 shown in FIG. 8) is defined as the "second direction." Furthermore, the direction from the lower side of the paper in FIG. 8 to the upper side of the paper (direction D3 shown in FIG. 8) is defined as the "third direction." The direction from the left side of the paper in FIG. 8 to the right side of the paper (direction D4 shown in FIG. 8) is defined as the "fourth direction."

[0024] (Flexible Wiring Board) As shown in Figures 1 and 4, the touch sensor 1 is provided with a flexible wiring board 8. The flexible wiring board 8 is configured to be flexible and to maintain its electrical characteristics even when deformed. The flexible wiring board 8 is made of a flexible insulating film such as PI (polyimide), PET (polyethylene terephthalate), or PEN (polyethylene naphthalate). The flexible wiring board 8 is attached to the peripheral portion of the sheet 3, which will be described later, located on the lower side of the paper surface in Figure 4.

[0025] 1 and 2, the touch sensor 1 includes a light-transmitting cover member 2. The cover member 2 is made of, for example, a cover glass or a plastic cover lens. The cover member 2 is formed, for example, in the shape of a rectangular plate in a plan view. The cover member 2 is fixed to a second layer 5 (see FIG. 3) of a sheet 3, which will be described later.

[0026] A substantially frame-shaped decorative portion 2a is formed on the periphery of the underside of the cover member 2 using a dark color such as black, for example, by screen printing. The rectangular area inside this decorative portion 2a serves as a light-transmitting view area. That is, the user can obtain visual information from the display unit 9, which will be described later, through this view area. The upper surface of the cover member 2 in the view area serves as an operation surface 2b of the touch sensor 1, which the user's fingers or the like come into contact with when performing a touch operation.

[0027] (Sheet) As shown in Figures 2 to 4, the touch sensor 1 includes a sheet 3. The sheet 3 is transparent. The sheet 3 is formed in a substantially rectangular shape in a plan view. The thickness of the sheet 3 is, for example, not less than 25 µm and not more than 200 µm.

[0028] As shown in FIG. 3, the sheet 3 has a first layer 4 and a second layer 5 .

[0029] The first layer 4 is made of a transparent resin material, such as polyethylene terephthalate (PET), polycarbonate (PC), cycloolefin polymer (COP), cycloolefin copolymer (COC), or polymethyl methacrylate (PMMA).

[0030] The second layer 5 is laminated on the upper side of the first layer 4. The second layer 5 is a layer for forming a plurality of grooves 6, which will be described later. The second layer 5 is made of an insulating and transparent resin material. The thickness of the second layer 5 is formed to be greater than the depth of the grooves 6, which will be described later.

[0031] A plurality of grooves 6 are provided on the upper surface 3a of the sheet 3 (surface of the second layer 5) (see FIG. 7). Each groove 6 has a bottom that is recessed from the upper surface 3a in the thickness direction of the sheet 3. The depth of each groove 6 is set to, for example, 0.8 μm or more and 4.0 μm or less. Although not shown, a plurality of grooves 6 are also provided on the lower surface 3b of the sheet 3.

[0032] (Adhesive Layer) As shown in Fig. 2, the touch sensor 1 includes an adhesive layer 7. The adhesive layer 7 is laminated between the cover member 2 and the sheet 3. The adhesive layer 7 is also laminated between the sheet 3 and a display unit 9 (described later). The adhesive layer 7 is an optically transparent adhesive (OCA: Optical Clear Adhesive). The thickness of the adhesive layer 7 is, for example, 25 µm or more and 250 µm or less.

[0033] (Display Unit) As shown in Fig. 2, a display unit 9 is provided on the underside of the sheet 3. The display unit 9 is laminated on the underside of the sheet 3 via an adhesive layer 7. Examples of the display unit 9 include a liquid crystal display (LCD) or an organic electroluminescence (EL) display device.

[0034] (Active Area and Inactive Area) As shown in Fig. 4, the touch sensor 1 is provided with an active area A and an inactive area B. The active area A has a rectangular shape in a plan view. The inactive area B has a rectangular frame shape. The inactive area B is arranged so as to surround the periphery of the active area A in a plan view.

[0035] (Sensor Electrodes) The touch sensor 1 includes a plurality of capacitive sensor electrodes. As shown in Fig. 4 , the plurality of sensor electrodes are configured by a plurality of transmitting electrodes 11 and a plurality of receiving electrodes 12. In the first embodiment of the present disclosure, the receiving electrodes 12 correspond to the first electrodes.

[0036] The plurality of transmitting electrodes 11 and the plurality of receiving electrodes 12 are arranged at positions on the sheet 3 corresponding to the active area A. The touch sensor 1 is capable of detecting a touch operation by a user's finger (detection target) that is in contact with the operation surface 2 b, through the plurality of transmitting electrodes 11 and the plurality of receiving electrodes 12 located in the active area A.

[0037] Each transmitting electrode 11 is connected to a drive circuit of an IC device (not shown) via a flexible wiring board 8. Each transmitting electrode 11 is configured to radiate an electric field to the surroundings by the drive circuit. A predetermined pulse potential for radiating the electric field is applied to the multiple transmitting electrodes 11.

[0038] Each receiving electrode 12 is connected to a detection circuit of an IC device (not shown) via a flexible wiring board 8. Each receiving electrode 12 is configured to detect an electric field radiated from each transmitting electrode 11. A predetermined potential is constantly applied to the multiple receiving electrodes 12 in order to detect the electric fields radiated from the multiple transmitting electrodes 11.

[0039] 4, the transmitting electrodes 11 and the receiving electrodes 12 are arranged to intersect (orthogonal to) each other in a plan view. A node is formed in the area where each transmitting electrode 11 and each receiving electrode 12 overlap. The node is configured as an area where electrostatic capacitance can be generated.

[0040] The plurality of transmitting electrodes 11 are provided on the lower surface 3b of the sheet 3 (see FIG. 2). As shown in FIGS. 4 and 5, each transmitting electrode 11 extends along the fourth direction D4. The plurality of transmitting electrodes 11 are arranged at intervals from one another in the third direction D3.

[0041] The plurality of receiving electrodes 12 are provided on the upper surface 3a of the sheet 3 (see FIG. 2). That is, the plurality of receiving electrodes 12 are arranged on the visible side of the touch sensor 1 (the side on which the operation surface 2b of the cover member 2 is located) of the sheet 3. The plurality of receiving electrodes 12 are insulated from the plurality of transmitting electrodes 11 via the sheet 3.

[0042] 4 and 6, each receiving electrode 12 extends along the third direction D3. The receiving electrodes 12 are arranged at intervals in the fourth direction D4.

[0043] Both the transmitter electrodes 11 and the receiver electrodes 12 are configured with a mesh pattern (see FIG. 8). As shown in FIGS. 8 and 9, this mesh pattern is formed so that a plurality of cells 13 are arranged in a line. The mesh pattern that configures each transmitter electrode 11 and the mesh pattern that configures each receiver electrode 12 are arranged so as to overlap each other in the thickness direction of the sheet 3.

[0044] The cell 13 is composed of a plurality of thin wires 20 that are electrically connected to one another. The cell 13 has a quadrilateral shape. In this embodiment, the quadrilateral shape is a rhombus. Although not shown, the quadrilateral shape may also be a square or a rectangle.

[0045] In this first embodiment, each cell 13 of the receiving electrode 12 (first electrode) adjacent to the buffer 41A described later is in a partially open state (non-closed state) in plan view due to the position of each third break portion 53 (described later) shown in Figure 9.

[0046] Each thin wire 20 is electrically conductive. Each thin wire 20 extends in the first direction D1 or the second direction D2 (see FIGS. 8 and 9 ). The line width of each thin wire 20 is, for example, 1 μm or more and 10 μm or less. The interval between adjacent thin wires 20, 20 is, for example, 100 μm or more and 500 μm or less.

[0047] (Cross-sectional structure of thin wires) Next, a cross-sectional structure of the thin wires 20 will be described. Each thin wire 20 includes a conductive metal buried in each groove 6. As shown in Fig. 7 , each thin wire 20 is composed of an adhesion layer 21, a seed layer 22, a conductive layer 23, and a blackening layer 24.

[0048] The adhesion layer 21 is an element for ensuring adhesion of the seed layer 22 to the groove portion 6. The adhesion layer 21 is, for example, a metal layer composed of a metal nitride or metal oxide containing at least one metal selected from the group consisting of Ti, Ni, Al, V, W, Ta, Si, Cr, Ag, Mo, Cu, and Zn. The adhesion layer 21 may be a single layer or a laminate in which multiple layers with different compositions are stacked. The adhesion layer 21 is stacked in the form of a thin film on the groove portion 6 by, for example, vapor deposition or sputtering.

[0049] The seed layer 22 has a function of bonding the conductive layer 23 to the adhesion layer 21. Specifically, the seed layer 22 functions as a cathode for depositing a plating solution containing copper (Cu) or the like, which will be described later, on the adhesion layer 21 in this embodiment, during, for example, an electroplating process for forming the conductive layer 23. The seed layer 22 is deposited as a thin film on the adhesion layer 21 by, for example, vapor deposition or sputtering.

[0050] The conductive layer 23 is made of a conductive metal such as copper (Cu). The conductive layer 23 is formed, for example, by electroplating. When the electroplating is performed, the seed layer 22 and the conductive layer 23 are formed integrally. This makes it impossible to distinguish the interface between the seed layer 22 and the conductive layer 23. Note that although copper (Cu) is suitable as the main component of the plating solution used in the electroplating, metals other than copper (for example, silver or gold) may also be included.

[0051] The blackening layer 24 has the function of making the thin wires 20 less visible when viewed from above the touch sensor 1. The blackening layer 24 is laminated on the surface of the conductive layer 23. The blackening layer 24 is formed by substituting palladium for copper crystal grains located at the boundaries between copper crystal grains located on the surface of the conductive layer 23 (blackening treatment). The thickness of the blackening layer 24 is, for example, 7 nm or more and 10 nm or less.

[0052] 4 to 6, the touch sensor 1 includes a plurality of wiring portions. The plurality of wiring portions are elements for electrically connecting the plurality of transmitting electrodes 11 and the plurality of receiving electrodes 12 to an IC device (mainly the above-mentioned drive circuit and detection circuit), not shown. Each wiring portion is made up of at least one thin wire 20.

[0053] The plurality of wiring sections are made up of a plurality of first wiring sections 25 and a plurality of second wiring sections 26. The plurality of first wiring sections 25 and the plurality of second wiring sections 26 are arranged in the inactive area B.

[0054] The first wiring portions 25 and the second wiring portions 26 are arranged at positions that overlap with the decorative portion 2a (see FIG. 2) when viewed from the side where the operation surface 2b is located. In other words, the first wiring portions 25 and the second wiring portions 26 are hidden from view from the side where the operation surface 2b is located by the decorative portion 2a.

[0055] 5, the plurality of first wiring portions 25 are arranged on the lower surface 3b of the sheet 3 (not shown), similarly to the plurality of transmitting electrodes 11. Each of the first wiring portions 25 is electrically connected to a corresponding transmitting electrode 11. One end of each of the first wiring portions 25 is electrically connected to an end of the corresponding transmitting electrode 11 located on the right side of the paper surface of FIG.

[0056] 6, the multiple second wiring portions 26 are arranged on the upper surface 3a of the sheet 3, similar to the multiple receiving electrodes 12. Each second wiring portion 26 is electrically connected to a corresponding receiving electrode 12. One end of each second wiring portion 26 is electrically connected to an end of the corresponding receiving electrode 12 that is located on the lower side of the paper surface of FIG.

[0057] 4 to 6, a pad 27 is provided at the other end of each wiring portion. Each pad 27 is made of at least one thin wire 20. Each pad 27 is electrically connected to flexible wiring board 8 via, for example, an anisotropic conductive film (ACF).

[0058] (Second Electrode) As shown in FIG. 8 , the touch sensor 1 includes a second electrode 30A that is not energized. In this embodiment, a plurality of second electrodes 30A are provided. Each second electrode 30A is electrically insulated from each receiving electrode 12 (first electrode). In other words, the second electrode 30A is configured as a so-called dummy electrode. Note that, for convenience of illustration, the plurality of second electrodes 30A are omitted from illustration in FIGS. 4 to 6 .

[0059] The second electrode 30A, like the receiving electrode 12 (first electrode), is formed on the upper surface 3a of the sheet 3. That is, the second electrode 30A is provided on the same surface of the sheet 3 as the receiving electrode 12 (first electrode). The second electrode 30A is disposed at a distance from the receiving electrode 12 (first electrode) in the fourth direction D4. In this embodiment, the distance between each receiving electrode 12 (first electrode) and the second electrode 30A in the fourth direction D4 corresponds to the dimension W3 shown in FIG. 8 .

[0060] 8, the second electrode 30A has a plurality of first thin wires 31 and a plurality of second thin wires 32. The line width of each of the first thin wires 31 and the second thin wires 32 is, for example, not less than 1 μm and not more than 10 μm. Each of the first thin wires 31 and the second thin wires 32 has a cross-sectional structure similar to that of the thin wire 20 described above.

[0061] Each of the first thin wires 31 extends along the first direction D1. The first thin wires 31 are arranged at intervals in a direction perpendicular to the first direction D1. The interval between adjacent first thin wires 31 is, for example, 100 μm or more and 500 μm or less.

[0062] Each second thin wire 32 extends in a direction different from the first direction D1. In this embodiment, each second thin wire 32 extends in the second direction D2. The multiple second thin wires 32 are arranged at intervals in a direction perpendicular to the second direction D2. The interval between adjacent second thin wires 32, 32 is, for example, 100 μm or more and 500 μm or less.

[0063] (Buffer) As shown in Figures 8 and 9, the touch sensor 1 includes a buffer 41A. In this embodiment, a plurality of buffers 41A are provided. For convenience of illustration, the multiple buffers 41A are not shown in Figures 4 to 6. In Figures 8 and 9, the outer shape of the buffer 41A is indicated by a virtual line.

[0064] Each buffer 41A is disposed between the receiving electrode 12 (first electrode) and the second electrode 30A in the fourth direction D4. That is, the buffer 41A is located outside the receiving electrode 12 (first electrode). Each buffer 41A is electrically insulated from both the receiving electrode 12 (first electrode) and the second electrode 30A adjacent to it in the fourth direction D4.

[0065] When viewed from above, the width of the buffer 41A in the fourth direction D4 is narrower than the width of the receiving electrode 12 (first electrode) in the fourth direction D4. When viewed from above, the width of the buffer 41A in the fourth direction D4 is narrower than the width of the second electrode 30A in the fourth direction D4. The width of the buffer 41A is equal to or smaller than the width of the cell 13. The width of the receiving electrode 12 (first electrode) corresponds to the dimension W1 in the fourth direction D4 (see FIGS. 6 and 8 ). The width of the second electrode 30A corresponds to the dimension W2 in the fourth direction D4 (see FIG. 8 ). The width of the buffer 41A corresponds to the distance between the receiving electrode 12 (first electrode) and the second electrode 30A in the fourth direction D4 (the dimension W3 shown in FIG. 8 ).

[0066] 9, the buffer 41A is formed of a plurality of unit structures 42. Each unit structure 42 has a third thin wire 43 and a fourth thin wire 44. The line width of each of the third thin wire 43 and the fourth thin wire 44 is, for example, not less than 1 μm and not more than 10 μm. Each of the third thin wire 43 and the fourth thin wire 44 has a cross-sectional structure similar to the cross-sectional structure of the thin wire 20 described above.

[0067] The third thin wire 43 is located on the same straight line as one of the plurality of first thin wires 31. Specifically, the third thin wire 43 is located along a virtual extension line of one of the plurality of first thin wires 31. The third thin wire 43 extends along the first direction D1.

[0068] The fourth thin wire 44 is located on the same straight line as one of the plurality of second thin wires 32. Specifically, the fourth thin wire 44 is located along a virtual extension line of one of the plurality of second thin wires 32. The fourth thin wire 44 extends along the second direction D2.

[0069] 9 , each of the third thin wire 43 and the fourth thin wire 44 has a first break portion 51, a second break portion 52, and a third break portion 53. In the first embodiment, one first break portion 51 is provided in the third thin wire 43, and one first break portion 51 is provided in the fourth thin wire 44.

[0070] The first broken portion 51 of the third thin wire 43 is formed in the middle of the third thin wire 43. Specifically, the first broken portion 51 of the third thin wire 43 is configured as a portion in the middle of the third thin wire 43 where the conductive material is missing.

[0071] The second broken portion 52 of the third thin wire 43 is located between the second electrode 30A and the end of the third thin wire 43. Specifically, the second broken portion 52 of the third thin wire 43 is configured as a portion where the conductive material is missing between the second electrode 30A and the end of the third thin wire 43.

[0072] The third broken portion 53 of the third thin wire 43 is located between the receiving electrode 12 (first electrode) and the end of the third thin wire 43. Specifically, the third broken portion 53 of the third thin wire 43 is configured as a portion where the conductive material is missing between the receiving electrode 12 (first electrode) and the end of the third thin wire 43.

[0073] The first broken portion 51 of the fourth thin wire 44 is located in the middle of the fourth thin wire 44. Specifically, the first broken portion 51 of the fourth thin wire 44 is configured as a portion in the middle of the fourth thin wire 44 where conductive material is missing.

[0074] The second broken portion 52 of the fourth thin wire 44 is located between the second electrode 30A and the end of the fourth thin wire 44. Specifically, the second broken portion 52 of the fourth thin wire 44 is configured as a portion where the conductive material is missing between the second electrode 30A and the end of the fourth thin wire 44.

[0075] The third break portion 53 of the fourth thin wire 44 is located between the receiving electrode 12 (first electrode) and the end of the fourth thin wire 44. Specifically, the third break portion 53 of the fourth thin wire 44 is configured as a portion where the conductive material is missing between the receiving electrode 12 (first electrode) and the end of the fourth thin wire 44.

[0076] In this first embodiment, the distance from the end of the third thin wire 43 to the first break portion 51 of the third thin wire 43 in the first direction D1 is approximately the same as the distance from the end of the fourth thin wire 44 to the first break portion 51 of the fourth thin wire 44 in the second direction D2.

[0077] In addition, in the first embodiment, the second electrode 30A and the buffer 41A are provided on the same plane as the receiving electrode 12, but the second electrode 30A and the buffer 41A may be provided on the same plane as the transmitting electrode 11. Furthermore, the transmitting electrode 11 and the receiving electrode 12 may each be provided with a structure corresponding to the second electrode 30A and a structure corresponding to the buffer 41A.

[0078] [Operation and Effect of First Embodiment] As described above, the touch sensor 1 includes the sheet 3, the receiving electrode 12 (first electrode) formed on the sheet 3, the second electrode 30A provided on the same surface (upper surface 3 a) of the sheet 3 as the surface on which the receiving electrode 12 (first electrode) is formed, electrically insulated from the receiving electrode 12 (first electrode), and a buffer 41A disposed between the first electrode and the second electrode 30A, electrically insulated from both the receiving electrode 12 (first electrode) and the second electrode 30A, and formed of a plurality of unit structures 42. The second electrode 30A has a plurality of first thin wires 31 extending along a first direction D1 and a plurality of second thin wires 32 extending along a second direction D2 different from the first direction D1. The unit structure 42 has a third thin wire 43 that is located in the same straight line as one of the multiple first thin wires 31 and extends along the first direction D1, and a fourth thin wire 44 that is located in the same straight line as one of the multiple second thin wires 32 and extends along the second direction D2.

[0079] In the touch sensor 1, by providing the second electrode 30A having the above-described configuration, when viewed by a user from the operation surface 2b side, the receiving electrode 12 (first electrode) having the plurality of thin wires 20 and the second electrode 30A having the plurality of first thin wires 31 and the plurality of second thin wires 32 become less noticeable. That is, in the touch sensor 1, the receiving electrode 12 (first electrode) becomes less noticeable compared to when the second electrode 30A is not provided. This prevents a decrease in visibility of the touch sensor 1.

[0080] Furthermore, the buffer 41A configured as described above includes a plurality of unit features 42 subdivided by the third thin wires 43 and the fourth thin wires 44. The buffer 41A, which is subdivided as a whole in this manner, is disposed between the receiving electrode 12 (first electrode) and the second electrode 30A. This reduces the occurrence of parasitic capacitance in the buffer 41A even if the buffer 41A is electrically affected by the receiving electrode 12 (first electrode) in a conducting state. The buffer 41A can also function to mitigate the electrical influence between the receiving electrode 12 (first electrode) and the second electrode 30A. This function reduces the electrical influence between the receiving electrode 12 (first electrode) and the second electrode 30A, which includes a plurality of first thin wires 31 and a plurality of second thin wires 32. In other words, even if the receiving electrode 12 (first electrode) is in a conducting state, the occurrence of parasitic capacitance in the second electrode 30A is suppressed. This makes it possible to maintain the capacitance that contributes to the sensor characteristics in the receiving electrode 12 (first electrode) in a normal state, thereby suppressing degradation of the sensor function in the receiving electrode 12 (first electrode).

[0081] Therefore, in the touch sensor 1 according to the first embodiment of the present disclosure, the visibility of the touch sensor 1 can be ensured and degradation of the sensor function can be suppressed.

[0082] In the first embodiment, the receiving electrode 12 (first electrode) extends along the third direction D3. The second electrode 30A extends along the third direction D3. The second electrode 30A is positioned in a fourth direction D4, which is perpendicular to the third direction D3, relative to the receiving electrode 12 (first electrode). That is, the second electrode 30A in the first embodiment is positioned outside the receiving electrode 12 (first electrode). This second electrode 30A makes it difficult for a user to distinguish between the receiving electrode 12 (first electrode) having the multiple thin wires 20 and the second electrode 30A having the multiple first thin wires 31 and the multiple second thin wires 32 when viewed from the operation surface 2b side. That is, the receiving electrode 12 (first electrode) is less noticeable in the touch sensor 1. This prevents a decrease in visibility of the touch sensor 1.

[0083] Furthermore, when viewed from above, the width of the buffer 41A in the fourth direction D4 is narrower than the width of the second electrode 30A, and when viewed from above, the width of the buffer 41A in the fourth direction D4 is narrower than the width of the second electrode 30A in the fourth direction D4. With this configuration, when a user views the touch sensor 1 from the operation surface 2b side, the buffer 41A, which has been subdivided as described above, is inconspicuous in comparison with the receiving electrode 12 (first electrode) and the second electrode 30A. This ensures the visibility of the touch sensor 1 even when the buffer 41A is disposed between the receiving electrode 12 (first electrode) and the second electrode 30A.

[0084] Furthermore, the third thin wire 43 is notched at its midpoint, and the fourth thin wire 44 is notched at its midpoint. That is, each of the third thin wire 43 and the fourth thin wire 44 has a first break 51 formed at or near the midpoint of the third thin wire 43. By providing this first break 51, it is possible to subdivide the buffer body 41A as a whole. As a result, even if the buffer body 41A is electrically affected by the energized receiving electrode 12 (first electrode), parasitic capacitance is less likely to occur in the buffer body 41A. Therefore, as described above, parasitic capacitance is less likely to occur in the second electrode 30A.

[0085] During the manufacturing process of the touch sensor 1, conductive foreign matter generated during the manufacturing process may adhere to the touch sensor 1. Even if the conductive foreign matter adheres to any of the first breakage portions 51, the buffer 41A is generally subdivided as described above, making it difficult for an electrical short circuit to occur between the receiving electrode 12 (first electrode) and the second electrode 30A. As a result, the touch sensor 1 can prevent the effects of the conductive foreign matter from occurring. Specifically, when the touch sensor 1 performs a touch operation with a user's finger or a touch pen, the sensor sensitivity to the touch operation does not decrease locally. Therefore, by each of the third thin wire 43 and the fourth thin wire 44 having the first breakage portion 51, the effects of the conductive foreign matter generated during the manufacturing process of the touch sensor 1 can also be reduced.

[0086] Additionally, each of the third thin wire 43 and the fourth thin wire 44 has a second break portion 52. The second break portion 52 of the third thin wire 43 is located at the end of the third thin wire 43 on the second electrode 30A side. The second break portion 52 of the fourth thin wire 44 is located at the end of the fourth thin wire 44 on the second electrode 30A side. The second break portion 52 can insulate the buffer 41A from the second electrode 30A.

[0087] [First Modification of First Embodiment] In the first embodiment described above, one first break portion 51 is formed in each of the midpoints of the third thin wire 43 and the fourth thin wire 44, but this is not limiting. That is, as in the first modification shown in Figures 10 and 11 , multiple (two in the illustrated example) first break portions 51 may be formed in each of the midpoints of the third thin wire 43 and the fourth thin wire 44. In other words, the third thin wire 43 may be cut out at two or more locations in its midpoint, and the fourth thin wire 44 may be cut out at two or more locations in its midpoint.

[0088] The two first breakage portions 51, 51 formed on the third thin wire 43 are spaced apart from each other in the third direction D3. The two first breakage portions 51, 51 formed on the fourth thin wire 44 are spaced apart from each other in the fourth direction D4.

[0089] In this first modification, the buffer 41A is further divided into smaller pieces. As a result, parasitic capacitance is further reduced in the buffer 41A. As a result, in this first modification, the generation of parasitic capacitance in the second electrode 30A is further reduced compared to the first embodiment. In other words, the degradation of the sensor function of the receiving electrode 12 (first electrode) can be further reduced.

[0090] Furthermore, in this first modification, by forming two first breakage portions 51, 51 in each of the third thin wire 43 and the fourth thin wire 44, it is possible to make the width of the buffer body 41A (dimension W3 shown in FIG. 10 ) larger than the width of the buffer body 41A in the first embodiment (dimension W3 shown in FIG. 8 ). That is, in this first modification, compared to the first embodiment, it is easier to move the second electrode 30A away from each receiving electrode 12 (first electrode) in the fourth direction D4. As a result, the second electrode 30A is less susceptible to electrical influence from the receiving electrode 12 (first electrode) in a conducting state, and the generation of parasitic capacitance in the second electrode 30A is further suppressed.

[0091] Although not shown, three or more first breaks 51 may be formed in the middle of each of the third thin wire 43 and the fourth thin wire 44. This further suppresses the generation of parasitic capacitance in the second electrode 30A. As a result, the capacitance value of the receiving electrode 12 (first electrode) can be made closer to the ideal capacitance value in a configuration that does not include the second electrode 30A.

[0092] In this first modified example, each of the third thin wires 43 and the fourth thin wires 44 has a second break portion 52. The effect of the second break portion 52 is similar to that of the first embodiment.

[0093] [Modification 2 of First Embodiment] As a modification 2 of the first embodiment, the second electrode 30A may be configured to be divided into a plurality of regions, as shown in Fig. 12. Note that the modification 2 shown in Fig. 12 is based on the configuration of the modification 1 shown in Fig. 10.

[0094] As shown in Fig. 12, the second electrode 30A is composed of a plurality of block portions 33a to 33d. The plurality of block portions 33a to 33d are electrically non-conductive to one another. In Fig. 12, the outline of each of the plurality of block portions 33a to 33d is indicated by imaginary lines.

[0095] The first thin wire 31 and the second thin wire 32 each have a fourth break portion 54 and a fifth break portion 55. The fourth break portion 54 and the fifth break portion 55 are configured as portions where conductive material is missing from the middle of the third thin wire 43 and the middle of the fourth thin wire 44, respectively.

[0096] The plurality of fourth break portions 54 are arranged along the third direction D3 or the fourth direction D4. The plurality of fifth break portions 55 are arranged along the third direction D3 or the fourth direction D4. Each of the plurality of block portions 33a to 33d is configured as an area in which the second electrode 30A is blocked by the plurality of fourth break portions 54 and the plurality of fifth break portions 55. With this configuration, the plurality of block portions 33a to 33d are electrically non-conductive to one another.

[0097] In this modification 2, by dividing the second electrode 30A into multiple regions, it is possible to reduce the parasitic capacitance in the second electrode 30A. Furthermore, due to a synergistic effect with the function of the buffer 41A described in the first embodiment, the occurrence of parasitic capacitance in the second electrode 30A is further suppressed. Therefore, in this modification 2, it is possible to further suppress the deterioration of the sensor function of the receiving electrode 12 (first electrode).

[0098] 13 and 14 show a touch sensor 1 according to a second embodiment of the present disclosure. In this embodiment, the positional relationship between the receiving electrode 12 (first electrode), the second electrode 30B, and the buffer 41B is different from the positional relationship between the receiving electrode 12 (first electrode), the second electrode 30A, and the buffer 41A shown in the first embodiment. In the second embodiment, the same elements as those shown in the first embodiment are denoted by the same reference numerals as those shown in the first embodiment, and detailed description of these components will be omitted.

[0099] 13 , in the second embodiment, the receiving electrode 12 (first electrode) has a plurality of grids 15. Specifically, the receiving electrode 12 (first electrode) in the second embodiment is configured with a mesh pattern in which a plurality of grids 15 are arranged.

[0100] As shown in Fig. 14, each grid 15 is composed of a plurality of thin wires 20 that are electrically connected to one another. In plan view, one grid 15 is larger than one cell 13 shown in the first embodiment. Each grid 15 has a quadrilateral shape. In this embodiment, the quadrilateral shape is a rhombus. Although not shown, the quadrilateral shape may also be a square or a rectangle.

[0101] Similar to the second electrode 30A of the first embodiment, the second electrode 30B has a plurality of first thin wires 31 and a plurality of second thin wires 32. Each second electrode 30B is provided inside each of the plurality of grids 15 of the receiving electrode 12 (first electrode). Each second electrode 30B is electrically insulated from each grid 15. Specifically, the second electrode 30B is disposed at a distance from each of the thin wires 20 constituting the grid 15 in the first direction D1 or the second direction D2. The distance between the second electrode 30B and each of the thin wires 20 constituting the grid 15 corresponds to the dimension W5 shown in FIG. 14 .

[0102] 13 and 14, the buffer 41B is located outside the second electrode 30B. Furthermore, the buffer 41B is located inside each of the plurality of grids 15.

[0103] The buffer 41B is disposed between the thin wires 20 of the lattice 15 constituting the receiving electrode 12 (first electrode) and the second electrode 30B. The buffer 41B is electrically insulated from both the lattice 15 of the receiving electrode 12 (first electrode) and the second electrode 30B.

[0104] In top view, the width of the buffer 41B in the first direction D1 (or the second direction D2) is narrower than the width of the first electrode in the first direction D1 (or the second direction D2). Furthermore, in top view, the width of the buffer 41B in the first direction D1 (or the second direction D2) is narrower than the width of the second electrode 30B in the first direction D1 (or the second direction D2). Here, the width of the first electrode corresponds to the dimension W1 shown in FIG. 6 , as in the first embodiment. The width of the second electrode 30B corresponds to the width dimension W4 (see FIG. 14 ) in the first direction D1 or the second direction D2. The width of the buffer 41B corresponds to the distance between the receiving electrode 12 (first electrode) and the second electrode 30B in the first direction D1 or the second direction D2 (dimension W5 shown in FIG. 14 ).

[0105] The buffer body 41B is formed by a plurality of unit structures 42. Each unit structure 42 has a third thin wire 43 and a fourth thin wire 44, similar to the first embodiment.

[0106] Also in this embodiment, each of the third thin wire 43 and the fourth thin wire 44 has a first break portion 51 , a second break portion 52 , and a third break portion 53 .

[0107] In this embodiment, the first broken portion 51 of the third thin wire 43 is configured as a portion where the conductive material is missing in the middle of the third thin wire 43. The second broken portion 52 of the third thin wire 43 is configured as a portion where the conductive material is missing between the second electrode 30B and the end of the third thin wire 43. The third broken portion 53 of the third thin wire 43 is configured as a portion where the conductive material is missing between the middle of the thin wire 20 that constitutes the lattice 15 and the end of the third thin wire 43.

[0108] The first broken portion 51 of the fourth thin wire 44 is configured as a portion where the conductive material is missing in the middle of the fourth thin wire 44. The second broken portion 52 of the fourth thin wire 44 is configured as a portion where the conductive material is missing between the second electrode 30B and the end of the fourth thin wire 44. The third broken portion 53 of the fourth thin wire 44 is configured as a portion where the conductive material is missing between the middle of the thin wire 20 that constitutes the lattice 15 and the end of the fourth thin wire 44.

[0109] In this embodiment, the second electrode 30B and the buffer 41B are provided on the same plane as the receiving electrode 12, but the second electrode 30B and the buffer 41B may be provided on the same plane as the transmitting electrode 11. Furthermore, the transmitting electrode 11 and the receiving electrode 12 may each be provided with a structure corresponding to the second electrode 30B and a structure corresponding to the buffer 41B.

[0110] [Effects of the Second Embodiment] In the touch sensor 1 according to the second embodiment, the second electrodes 30B are provided inside the grids 15 of the receiving electrode 12 (first electrodes). This makes it difficult for a user to distinguish between the receiving electrode 12 (first electrodes) having the grids 15 and the second electrodes 30B when viewed from the operation surface 2b side. That is, the receiving electrodes 12 (first electrodes) are less noticeable in the touch sensor 1. This prevents a decrease in visibility in the touch sensor 1.

[0111] Furthermore, the buffer 41B of the second embodiment also includes a plurality of unit features 42 segmented by the third thin wires 43 and the fourth thin wires 44. Furthermore, the buffer 41B of the second embodiment is located outside the second electrode 30B and inside each of the plurality of grids 15. That is, the segmented buffer 41B is disposed between the receiving electrode 12 (first electrode) and the second electrode 30B. This reduces the likelihood of parasitic capacitance occurring in the buffer 41B even if the buffer 41B is electrically affected by the energized receiving electrode 12 (first electrode). The buffer 41B can also function to mitigate the electrical influence between the receiving electrode 12 (first electrode) and the second electrode 30B. This function reduces the electrical influence of the energized receiving electrode 12 (first electrode) on the second electrode 30B, which includes a plurality of first thin wires 31 and a plurality of second thin wires 32. That is, even if the receiving electrode 12 (first electrode) is in a conducting state, the generation of parasitic capacitance in the second electrode 30B is suppressed. This makes it easier to maintain a normal capacitance value in the receiving electrode 12 (first electrode). As a result, the degradation of the sensor function of the receiving electrode 12 (first electrode) is suppressed.

[0112] Furthermore, in a top view, the width of the buffer 41B in the first direction D1 is narrower than the width of the second electrode 30B in the first direction D1. With this configuration, when a user views the touch sensor 1 from the operation surface 2b side, the subdivided buffer 41B is inconspicuous in comparison with the receiving electrode 12 (first electrode) and the second electrode 30B. In this way, even if the buffer 41B is disposed between the receiving electrode 12 (first electrode) and the second electrode 30B, the visibility of the touch sensor 1 is ensured.

[0113] Therefore, even in the second embodiment of the present disclosure, the visibility of the touch sensor 1 can be ensured and degradation of the sensor function can be suppressed.

[0114] [Modification of Second Embodiment] As a modification of the second embodiment, the plurality of sixth breakage portions 56 and the plurality of seventh breakage portions 57 shown in FIG. 15 may be provided in the second electrode 30B.

[0115] A plurality of sixth breakage portions 56 are formed in the first thin wire 31. Each sixth breakage portion 56 is configured as a portion in the middle of the first thin wire 31 where the conductive material is missing.

[0116] A plurality of seventh breakage portions 57 are formed in the second thin wire 32. Each of the seventh breakage portions 57 is configured as a portion in the middle of the second thin wire 32 where the conductive material is missing.

[0117] In this modification, by providing the second electrode 30B with the plurality of sixth breaks 56 and the plurality of seventh breaks 57, it is possible to further reduce the parasitic capacitance in the second electrode 30B. Furthermore, due to a synergistic effect with the function of the buffer 41B described in the second embodiment, the parasitic capacitance is less likely to occur in the second electrode 30B. Therefore, in this modification, it is possible to further suppress the deterioration of the sensor function of the receiving electrode 12 (first electrode).

[0118] [Other Embodiments Common to Both the First and Second Embodiments] In the first and second embodiments, the rectangular active area A is used, but the present invention is not limited to this. The active area A may have a polygonal shape other than a rectangular shape in a plan view.

[0119] In the first and second embodiments, the plurality of transmitting electrodes 11 and the plurality of first wiring portions 25 are arranged on the lower surface 3b of the sheet 3, and the plurality of receiving electrodes 12 (first electrodes), the plurality of second wiring portions 26, the plurality of second electrodes 30, and the plurality of buffers 41A (or the plurality of buffers 41B) are arranged on the upper surface 3a of the sheet 3. However, this is not limiting. For example, although not shown, the plurality of transmitting electrodes 11 and the plurality of first wiring portions 25 may be arranged on the upper surface 3a, and the plurality of receiving electrodes 12 (first electrodes), the plurality of second wiring portions 26, the plurality of second electrodes 30, and the plurality of buffers 41A (or the plurality of buffers 41B) may be arranged on the lower surface 3b.

[0120] In the first and second embodiments, the touch sensor 1 is shown in a state in which the cover member 2 and the flexible wiring board 8 are attached to the sheet 3, but this is not limiting. That is, the concept of the touch sensor 1 includes a state before the cover member 2, the flexible wiring board 8, and the like are attached to the sheet 3. Furthermore, the concept of the touch sensor 1 also includes a configuration in which the above-described plurality of transmitting electrodes 11, plurality of receiving electrodes 12 (first electrodes), plurality of first wiring portions 25, plurality of second wiring portions 26, plurality of pads 27, plurality of second electrodes 30, and plurality of buffers 41A (or plurality of buffers 41B) are formed on a long base material (e.g., a long hoop-shaped member not shown) in a state before the sheets 3 are individually formed.

[0121] In the first embodiment described above, the distance from the end of the third thin wire 43 to the first break portion 51 of the third thin wire 43 in the first direction D1 is approximately the same as the distance from the end of the fourth thin wire 44 to the first break portion 51 of the fourth thin wire 44 in the second direction D2 (see FIG. 9 ). However, the present invention is not limited to this. For example, as shown in FIG. 16 , in the first embodiment described above, the distance L1 from the end of the third thin wire 43 to the first break portion 51 of the third thin wire 43 in the first direction D1 may be different from the distance L2 from the end of the fourth thin wire 44 to the first break portion 51 of the fourth thin wire 44 in the second direction D2. 17 , in the second embodiment, the distance L3 from the end of the third thin wire 43 to the first break portion 51 of the third thin wire 43 in the first direction D1 may be different from the distance L4 from the end of the fourth thin wire 44 to the first break portion 51 of the fourth thin wire 44 in the second direction D2. The distance from the end of the third thin wire 43 to the notch of the third thin wire 43 in the first direction D1 is different from the distance from the end of the fourth thin wire 44 to the notch of the fourth thin wire 44 in the second direction D2. That is, the break positions for forming the first break portions 51 of the third thin wire 43 and the fourth thin wire 44 shown in FIGS. 16 and 17 are offset from each other. This makes it difficult for a user to distinguish the first break portion 51 of the third thin wire 43 from the first break portion 51 of the fourth thin wire 44 when viewing the buffer 41 from the operation surface 2b side. That is, the buffer 41A or 41B becomes even less noticeable in the touch sensor 1. Therefore, the decrease in visibility of the touch sensor 1 can be further prevented.

[0122] In the first embodiment, a configuration in which a portion of each cell 13 of the receiving electrode 12 (first electrode) adjacent to the buffer 41A is in an open state (unclosed state) has been described. However, this configuration is not limited to this. For example, as shown in FIG. 18 , each cell 13 of the receiving electrode 12 (first electrode) adjacent to the buffer 41A may be configured to be in a closed state. Note that in the configuration shown in FIG. 18 , the dimension W3 can be made smaller than the dimension W3 of FIG. 8 in the first embodiment. Even in the configuration shown in FIG. 18 , the effects of the first embodiment described above can be achieved. Furthermore, the configuration shown in FIG. 18 may also be used in each of the modified examples of the first embodiment ( FIGS. 10 , 11 , 12 , and 16 ).

[0123] The present disclosure is industrially applicable as a touch sensor.

[0124] 1: Touch sensor 2: Cover member 3: Sheet 11: Transmitting electrode 12: Receiving electrode (first electrode) 15: Lattice 20: Thin wire 25: First wiring portion 26: Second wiring portion 30A, 30B: Second electrode 31: First thin wire 32: Second thin wire 33: Block portion 41A, 41B: Cushioning body 52: Unit structure 43: Third thin wire 44: Fourth thin wire 51: First broken portion 52: Second broken portion 53: Third broken portion 54: Fourth broken portion 55: Fifth broken portion 56: Sixth broken portion 57: Seventh broken portion

Claims

1. A touch sensor comprising: a sheet; a first electrode formed on the sheet; a second electrode provided on the same surface of the sheet as the first electrode, electrically insulated from the first electrode and not conducting electricity; a buffer disposed between the first electrode and the second electrode, electrically insulated from both the first electrode and the second electrode, and formed of a plurality of unit structures; wherein the second electrode has a plurality of first thin wires extending along a first direction and a plurality of second thin wires extending along a second direction different from the first direction; and the unit structure has: a third thin wire located on the same straight line as one of the plurality of first thin wires and extending along the first direction; and a fourth thin wire located on the same straight line as one of the plurality of second thin wires and extending along the second direction.

2. The touch sensor of claim 1, wherein the first electrode extends along a third direction, the second electrode extends along the third direction and is located in a fourth direction perpendicular to the third direction relative to the first electrode, the width of the buffer body along the fourth direction when viewed from above is narrower than the width of the first electrode along the fourth direction, and the width of the buffer body along the fourth direction when viewed from above is narrower than the width of the second electrode along the fourth direction.

3. The touch sensor according to claim 1, wherein the first electrode further has a plurality of lattices, the second electrode is provided inside each of the plurality of lattices of the first electrode, the buffer is located outside the second electrode, the buffer is located inside each of the plurality of lattices, and the width of the buffer along the first direction in a top view is narrower than the width of the second electrode along the first direction.

4. The touch sensor according to claim 1, wherein the third thin wire is notched at a midpoint thereof, and the fourth thin wire is notched at a midpoint thereof.

5. The touch sensor according to claim 4, wherein the third thin wire is notched at two or more locations midway along the third thin wire, and the fourth thin wire is notched at two or more locations midway along the fourth thin wire.

6. A touch sensor as described in claim 4 or 5, wherein the distance from the end of the third thin wire to the notch in the third thin wire in the first direction is different from the distance from the end of the fourth thin wire to the notch in the fourth thin wire in the second direction.

7. The touch sensor according to any one of claims 1 to 6, wherein the second electrode is composed of a plurality of block portions that are electrically non-conductive to each other.

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