Touch sensor

Abstract

A first reception electrode (Rx3) has a first extension part (12a) that is positioned between a first electrode body (10a) and a second electrode body (10b) and extends from the first electrode body (10a). The first extension part (12a) of the first reception electrode (Rx3) is separated from the second electrode body (10b). A first farthest part (19a) of the first extension part (12a), which is at a position farthest from the first electrode body (10a) in a first direction (D1), is positioned more toward the first direction (D1) than an end part of the second electrode body (10b) in a direction opposite to the first direction (D1).

Description

Touch Sensor

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

[0002] 2. Description of the Related Art Conventionally, a capacitive touch sensor is known, for example, as disclosed in Japanese Patent Application Laid-Open No. 2003-149999.

[0003] Specifically, Patent Document 1 discloses a touch sensor (touch panel) as an input device. The touch sensor has a plurality of drive electrodes and a plurality of detection electrodes. The plurality of drive electrodes extend in the X-axis direction and are arranged along the Y-axis direction that intersects with the X-axis direction. The plurality of detection electrodes extend in the Y-axis direction and are arranged along the X-axis direction.

[0004] The detection electrode includes a main body and a plurality of protruding portions (extension portions). In a plan view, the protruding portions protrude in strip-like shapes from an intersection area of ​​the main body where the detection electrode intersects with the drive electrode in the positive and negative directions of the X-axis (see, for example, FIG. 7 of Patent Document 1). The protruding portions function as extension portions to expand the area of ​​the detection electrode.

[0005] JP 2014-153840 A

[0006] In the touch sensor of Patent Document 1, adjacent detection electrodes Rx1 and Rx2 have a protruding portion that protrudes from the main body of Rx1 in the positive direction of the X-axis and a protruding portion that protrudes from the main body of Rx2 in the negative direction of the X-axis, and these protruding portions face each other at a predetermined distance (see, for example, FIG. 7 of Patent Document 1). The tip of the protruding portion that protrudes from the main body of Rx1 is spaced apart in the negative direction of the X-axis from the intersection area between the main body of Rx2 and the drive electrode. Similarly, the tip of the protruding portion that protrudes from the main body of Rx2 is spaced apart in the positive direction of the X-axis from the intersection area between the main body of Rx1 and the drive electrode.

[0007] In the above configuration, for example, when a detection object (a user's finger or a touch pen) touches directly above the main body of Rx1, a touch action is detected in the intersection area between the main body of Rx1 and the drive electrode. Also, for example, when a detection object touches near the protruding portion of Rx1, a touch action is detected in the intersection area between the main body of Rx1 and the drive electrode. That is, not only when a detection object touches directly above the main body, but also when a detection object touches a location slightly away from the main body (near the protruding portion), the function of the protruding portion described above allows the intersection area between the main body and the drive electrode to monopolize touch sensitivity.

[0008] Therefore, even if the detection object touches the tip of the protruding portion of Rx1, the touch action is detected as being located at the position where the touch action was made (hereinafter simply referred to as the "touch position") in the intersection area between the main body of Rx1 and the drive electrode. In other words, the touch position by the detection object is detected as being located in a position biased toward the intersection area between the main body of the detection electrode and the drive electrode, rather than the actual touch position (in the above example, a position near the middle between Rx1 and Rx2). As such, the touch sensor of Patent Document 1 may have reduced accuracy in detecting the touch position.

[0009] If the detection accuracy of the touch position is reduced, it becomes difficult to accurately and appropriately detect, for example, continuous touch actions in which the detection object moves linearly or curvedly using multiple detection electrodes. Furthermore, when the touch sensor is enlarged, the distance between the detection electrodes generally tends to increase, which causes a problem that the actual trajectory (e.g., handwriting) of the continuous touch actions is likely to be misaligned from the detection result of the continuous touch actions.

[0010] The present disclosure has been made in view of the above points, and has as its object to accurately and appropriately detect a touch action of a detection target.

[0011] To achieve the above object, a touch sensor according to one embodiment of the present disclosure includes: a transmitting electrode extending along a first direction; a first receiving electrode formed by a first thin wire; and a second receiving electrode formed by a second thin wire; the first receiving electrode extending along a second direction orthogonal to the first direction and having a first electrode body intersecting the transmitting electrode in a plan view; the second receiving electrode extending along the second direction and having a second electrode body intersecting the transmitting electrode in a plan view; the second receiving electrode being positioned in the first direction of the first receiving electrode. The first receiving electrode further includes a first extension portion positioned between the first electrode body and the second electrode body and extending from the first electrode body. The first extension portion of the first receiving electrode is spaced apart from the second electrode body. In the first direction, a first farthest portion of the first extension portion, which is located farthest from the first electrode body, is positioned in the first direction relative to an end of the second electrode body in a direction opposite to the first direction.

[0012] According to the present disclosure, it is possible to accurately and appropriately detect a touch action of a detection target.

[0013] FIG. 1 is an overall perspective view of a touch sensor according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1 . FIG. 3 is a perspective view schematically illustrating the configuration of a transmitting electrode and a receiving electrode when viewed from the front surface side of a substrate. FIG. 4 is a schematic view of the transmitting electrode when viewed from the back surface side of the substrate. FIG. 5 is a partial enlarged view of section V shown in FIG. 4 . FIG. 6 is a schematic view of the receiving electrode when viewed from the front surface side of the substrate. FIG. 7 is a partial enlarged view of section VII shown in FIG. 3 . FIG. 8 is a schematic view of the configuration of a cell and a first extension portion constituting a first electrode main body. FIG. 9 is a schematic view of the configuration of a cell and a second extension portion constituting a second electrode main body. FIG. 10 is a cross-sectional view showing the cross-sectional structure of a thin wire. FIG. 11 is a perspective view schematically illustrating the configuration of a transmitting electrode and a receiving electrode when viewed from the front surface side of a substrate in Modification 1. FIG. 12 is a partial enlarged view of section XII shown in FIG. 11 . FIG. 13 is a perspective view schematically illustrating the configuration of a transmitting electrode and a receiving electrode when viewed from the front surface side of a substrate in Modification 2. FIG. 14 is a partial enlarged view of the portion XIV shown in FIG.

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The following description of the embodiments is merely exemplary in nature and is not intended to limit the present disclosure, its applications, or its uses.

[0015] 1 shows an entire touch sensor 1 according to an embodiment of the present disclosure. The touch sensor 1 is a capacitance-type sensor-type input device that is applied to a display 100 (see FIG. 2). The touch sensor 1 is used as an input device for, for example, in-vehicle devices such as car navigation systems, display devices for personal computers, mobile phones, personal digital assistants, portable game machines, copy machines, ticket vending machines, automated teller machines, watches, and the like.

[0016] In the following description, the side on which an operation surface 2b (see FIGS. 1 and 2) of a cover member 2, which will be described later, is located will be referred to as the "front side" of the touch sensor 1, and the opposite side will be referred to as the "back side" of the touch sensor 1, and the positional relationship of each element constituting the touch sensor 1 will be defined accordingly. In addition, in this embodiment, for the sake of convenience of description, the direction from the left side to the right side of the paper in FIG. 3 will be defined as the "first direction D1," and the direction from the bottom side to the top side of the paper in FIG. 3 will be defined as the "second direction D2."

[0017] 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. 10) of a substrate 3, which will be described later.

[0018] A roughly frame-shaped decorative portion 2a is formed in a dark color such as black by screen printing or the like around the periphery of the back surface of the cover member 2. The rectangular area inside this decorative portion 2a is a light-transmitting view area Va. That is, the user can obtain visual information from a display arranged on the back side of the touch sensor 1 through this view area Va. The surface of the cover member 2 in the view area Va is configured as an operation surface 2b that comes into contact with the user's fingers or the like when performing a touch operation.

[0019] 2 to 4 and 6, the touch sensor 1 includes one substrate 3. A first surface 3a of the substrate 3 corresponds to the back surface of the substrate 3 (see FIGS. 2 and 4). A second surface 3b of the substrate 3 corresponds to the front surface of the substrate 3 (see FIGS. 2, 3 and 6).

[0020] 10, the substrate 3 has a first layer 4 and a second layer 5. Each of the first layer 4 and the second layer 5 is formed, for example, in a substantially rectangular shape in a plan view.

[0021] The first layer 4 is made of a transparent resin material, such as polyethylene terephthalate (PET), polycarbonate (PC), cycloolefin polymer (COP), or cycloolefin copolymer (COC).

[0022] The second layer 5 is laminated on the surface of the first layer 4. Although not shown, in this embodiment, the second layer 5 is also laminated on the back surface 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 set to, for example, 1.0 μm or more and 10.0 μm or less to ensure flexibility. The thickness of the second layer 5 is also formed to be greater than the depth of the grooves 6, which will be described later.

[0023] A plurality of grooves 6 are provided on the surface of the second layer 5. Although not shown, a plurality of grooves 6 are also provided on the back surface of the second layer 5. Each groove 6 has a bottom that is recessed in the thickness direction of the substrate 3. The depth of each groove 6 is set to, for example, not less than 0.9 μm and not more than 3.0 μm.

[0024] 2 , the touch sensor 1 includes an adhesive layer 7. The adhesive layer 7 is laminated between the cover member 2 and the substrate 3. 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.

[0025] 1, the touch sensor 1 includes 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).

[0026] (Sensor Electrodes) The touch sensor 1 includes a plurality of capacitance-type sensor electrodes. The plurality of sensor electrodes are configured of a plurality of transmitting electrodes Tx (Tx1 to Tx5) and a plurality of receiving electrodes Rx (Rx1 to Rx5) (see FIG. 3).

[0027] Hereinafter, for convenience of explanation, the receiving electrode Rx3 may be referred to as the “first receiving electrode Rx3,” and the receiving electrode Rx4 may be referred to as the “second receiving electrode Rx4.” The second receiving electrode Rx4 is located in the first direction D1 of the first receiving electrode Rx3 (see FIG. 7).

[0028] 7, the first receiving electrode Rx3 has a first electrode body 10a (described later) and a first extension portion 12a (described later), and the second receiving electrode Rx4 has a second electrode body 10b (described later) and a second extension portion 12b (described later).

[0029] The plurality of transmitting electrodes Tx and the plurality of receiving electrodes Rx are arranged at positions corresponding to the view area Va (see FIG. 1 ) on the substrate 3. The touch sensor 1 is capable of detecting a touch operation by a user's finger (detection target) that touches the operation surface 2 b through the plurality of transmitting electrodes Tx and the plurality of receiving electrodes Rx located within the view area Va.

[0030] Each transmitting electrode Tx is connected to a drive circuit (not shown) via a flexible wiring board 8. Each transmitting electrode Tx is configured to radiate an electric field to the surroundings via this drive circuit. Meanwhile, each receiving electrode Rx is connected to a detection circuit (not shown) via a flexible wiring board 8. Each receiving electrode Rx is configured to receive the electric field radiated from each transmitting electrode Tx.

[0031] As shown in FIG. 3, the transmitting electrodes Tx and the receiving electrodes Rx intersect (are orthogonal to) each other in a plan view.

[0032] 2 and 4, a plurality of transmitting electrodes Tx (Tx1 to Tx5) are provided on a first surface 3a (the back surface side of the substrate 3) of the substrate 3. Each transmitting electrode Tx extends along a first direction D1. The plurality of transmitting electrodes Tx are arranged at intervals from one another in a second direction D2.

[0033] The width EW1 of the transmitting electrodes Tx (see FIG. 4) is set to, for example, 2 mm to 6 mm, and the spacing ES between the transmitting electrodes Tx (see FIG. 5) is set to, for example, 1 μm to 20 μm.

[0034] 2 and 6, the plurality of receiving electrodes Rx (Rx1 to Rx5) are provided on the second surface 3b (the front surface side of the substrate 3) of the substrate 3. That is, the plurality of receiving electrodes Rx are arranged on the substrate 3 on the viewing side of the touch sensor 1 (the side on which the operation surface 2b of the cover member 2 is located). The plurality of receiving electrodes Rx are insulated from the plurality of transmitting electrodes Tx via the substrate 3. Each receiving electrode Rx extends along the second direction D2. The plurality of receiving electrodes Rx are arranged at intervals from one another in the first direction D1.

[0035] Each transmitter electrode Tx is configured in a mesh pattern (see FIG. 5). Each receiver electrode Rx (cell 11 and extension portions 12, 12, which will be described later) is also configured in a mesh pattern (see FIGS. 8 and 9).

[0036] 5, 8, and 9, the mesh pattern is made up of a plurality of fine wires 20. Specifically, the mesh pattern has a mesh structure in which the plurality of fine wires 20 intersect with each other and are arranged at equal intervals. The mesh patterns constituting each transmitting electrode Tx and the mesh patterns constituting each receiving electrode Rx are arranged so as to overlap each other in the thickness direction of the substrate 3.

[0037] Each of the thin wires 20 is electrically conductive. The thin wires 20 extend obliquely with respect to each of the first direction D1 and the second direction D2. The width of each of the thin wires 20 is, for example, 1 μm or more and 3 μm or less. The cross-sectional structure of the thin wires 20 will be described later.

[0038] Here, as shown in Fig. 8, the first receiving electrode Rx3 is formed by a first thin wire 20a. Also, as shown in Fig. 9, the second receiving electrode Rx4 is formed by a second thin wire 20b. Note that both the first thin wire 20a and the second thin wire 20b have the same configuration as the thin wire 20.

[0039] Next, the transmitting electrode Tx is provided with a wiring portion (not shown). The wiring portion is connected to an end portion of the transmitting electrode Tx. Specifically, the wiring portion is connected to the end portion of the transmitting electrode Tx shown in FIG. 3 located on the right side of the paper (the end portion located on the left side of the paper in FIG. 4). The wiring portion is made of a thin wire similar to the thin wire 20.

[0040] The receiving electrode Rx is also provided with a wiring portion (not shown). The wiring portion is connected to an end portion of the receiving electrode Rx of the electrode body 10 (described later). Specifically, the wiring portion is connected to an end portion of the electrode body 10 shown in FIGS. 3 and 6 that is located on the lower side of the paper.

[0041] (Main Area) As shown in Figures 3 and 6, each receiving electrode Rx is provided with a main area Ma. The main area Ma is an area capable of receiving an electric field radiated from each transmitting electrode Tx. The main area Ma extends along the second direction D2. The main area Ma has a substantially strip shape.

[0042] The width dimension EW2 of the main area Ma is configured to be smaller than the width dimension EW1 of the transmitting electrodes Tx. Specifically, the width dimension EW2 is, for example, 2 mm or more.

[0043] In the plurality of receiving electrodes Rx, the plurality of main areas Ma are arranged at intervals from each other in the first direction D1. In this embodiment, the plurality of main areas Ma are arranged at equal intervals in the first direction D1.

[0044] In this embodiment, the pitch EP between the main areas Ma, Ma is configured to be smaller than the width dimension EW2 of the main areas Ma (see FIG. 3). Specifically, the pitch EP is, for example, 3 mm or more and 7 mm or less.

[0045] (Nodes) As shown in Fig. 7 , nodes N are formed in regions where each transmitting electrode Tx intersects with each main area Ma. The nodes N are configured as regions capable of generating capacitance. The capacitance value of the nodes N is determined by the number of intersections between the multiple thin wires 20 that make up each transmitting electrode Tx and the multiple thin wires 20 that make up each main area Ma. For ease of explanation, the nodes N in Fig. 7 are hatched with dots to emphasize the nodes N that correspond to the positions where the transmitting electrode Tx3 intersects with the main areas Ma of the receiving electrodes Rx3 and Rx4.

[0046] 7, the first receiving electrode Rx3 forms a first node N1 that generates capacitance in a region where it intersects with the transmitting electrode Tx, and the second receiving electrode Rx4 forms a second node N2 that generates capacitance in a region where it intersects with the transmitting electrode Tx.

[0047] 6 and 7 , each receiving electrode Rx has an electrode body 10. The electrode body 10 is arranged in the main area Ma. That is, in the multiple receiving electrodes Rx, the multiple electrode bodies 10 are arranged at intervals from each other in the first direction D1.

[0048] In the following, for ease of explanation, the electrode body 10 on the side of the first receiving electrode Rx3 shown in FIG. 7 (the electrode body 10 located on the left side of the paper in FIG. 7) will be referred to as the "first electrode body 10a," and the electrode body 10 on the second receiving electrode Rx4 shown in FIG. 7 (the electrode body 10 located on the right side of the paper in FIG. 7) will be referred to as the "second electrode body 10b."

[0049] The first electrode body 10a intersects with the transmitting electrode Tx in a plan view, and the second electrode body 10b intersects with the transmitting electrode Tx in a plan view.

[0050] 7, the electrode body 10 is composed of a plurality of cells 11. The plurality of cells 11 are arranged in a main area Ma. The plurality of cells 11 are arranged so as to be aligned in a line along the extension direction of the main area Ma (i.e., the second direction D2).

[0051] As shown in Figures 8 and 9, the cells 11 have a rectangular shape. This rectangular shape is formed by imaginary first and second diagonal lines DL1 and DL2. The second diagonal line DL2 is set to be longer than the first diagonal line DL1. In this embodiment, the rectangular shape is a rhombus. As described above, each cell 11 is configured with a mesh pattern made up of a plurality of thin wires 20. Note that, in each electrode body 10 shown in Figure 6, the cells 11 located at the upper side of the paper in Figure 6 are formed in a generally V-shape with an open upper portion, while the cells 11 located at the lower side of the paper in Figure 6 are formed in a generally pentagonal shape.

[0052] Here, a dummy pattern (not shown) may be arranged inside each cell 11. Furthermore, a dummy electrode (not shown) may be arranged between adjacent electrode bodies 10. Both the dummy pattern and the dummy electrode are composed of a plurality of thin wires 20.

[0053] In the following, for the sake of convenience, the reference numerals for the cells constituting the first electrode body 10a shown in Figures 7 and 8 will be "11a", and the reference numerals for the cells constituting the second electrode body 10b shown in Figures 7 and 9 will be "11b".

[0054] 6 to 9, each receiving electrode Rx has a plurality of extension portions 12. The plurality of extension portions 12 are electrically connected to the electrode body 10. Specifically, each extension portion 12 is electrically connected to each cell 11. As described above, each extension portion 12 is configured by a mesh pattern made up of a plurality of thin wires 20.

[0055] Each extension portion 12 branches off from each cell 11 of the electrode body 10 in a direction different from the second direction D2. As shown in Figures 8 and 9, each extension portion 12 is configured so that a width dimension WD2 in a direction perpendicular to the extension direction is smaller than a width dimension WD1 of the outline of each cell 11. Specifically, the width dimension WD2 is approximately half the width dimension WD1.

[0056] Here, in the receiving electrode Rx located on the left side of the paper in Fig. 6, the multiple extension portions 12 are arranged only on the right side of the electrode main body 10. Also, in the receiving electrode Rx located on the right side of the paper in Fig. 6, the multiple extension portions 12 are arranged only on the left side of the electrode main body 10. In contrast, in the receiving electrodes Rx located at positions other than the left and right sides of the paper in Fig. 6, the multiple extension portions 12 are arranged on both the left and right sides of the electrode main body 10.

[0057] In the following, for ease of explanation, the extension portion 12 on the first electrode main body 10a side shown in Figure 7 will be referred to as the "first extension portion 12a," and the extension portion 12 on the second electrode main body 10b side shown in Figure 7 will be referred to as the "second extension portion 12b."

[0058] 7 , the first extension portion 12a is located between the first electrode main body 10a and the second electrode main body 10b and extends from the first electrode main body 10a. The first extension portion 12a of the first receiving electrode Rx3 is spaced apart from the second electrode main body 10b. In the first direction D1, the first farthest portion 19a of the first extension portion 12a, which is located farthest from the first electrode main body 10a, is located further in the first direction D1 than the end of the second electrode main body 10b in the direction opposite to the first direction D1. A portion of the first extension portion 12a overlaps with the second node N2 in a plan view.

[0059] As shown in FIGS. 7 and 8, the first expanding portion 12a includes a first connecting portion 13a, a first intruding portion 14a, and a first complementary portion 15a.

[0060] The first connecting portion 13a connects the first electrode body 10a of the first receiving electrode Rx3 and the first inserted portion 14a. The first connecting portion 13a extends in a zigzag shape.

[0061] The first intruding portion 14a is connected to the end of the first connecting portion 13a located opposite the cell 11a. The first intruding portion 14a extends obliquely with respect to both the first direction D1 and the second direction D2. In FIG. 8, the first intruding portion 14a is surrounded by a dashed line to clearly show the position and range of the first intruding portion 14a.

[0062] The first intruding portion 14a extends along the outline of the second electrode body 10b of the second receiving electrode Rx4. The farthest portion of the first intruding portion 14a in the first direction D1 is the first farthest portion 19a of the first extending portion 12a in the first direction D1.

[0063] 7, the second extension portion 12b is located between the first electrode body 10a and the second electrode body 10b and extends from the second electrode body 10b. The second extension portion 12b of the second receiving electrode Rx4 is spaced apart from the first electrode body 10a.

[0064] As shown in FIGS. 7 and 9, the second expanding portion 12b includes a second connecting portion 13b, a second intruding portion 14b, and a first complementary portion 15b.

[0065] The second connecting portion 13b connects the second electrode body 10b of the second receiving electrode Rx4 and the second inserting portion 14b. The second connecting portion 13b extends in a zigzag shape.

[0066] The second intrusion portion 14b is connected to the end of the second connection portion 13b located opposite the cell 11b. The second intrusion portion 14b extends obliquely with respect to both the first direction D1 and the second direction D2. In FIG. 9, the second intrusion portion 14b is surrounded by a dashed line to clearly show the position and range of the second intrusion portion 14b.

[0067] 7, the second farthest portion 19b of the second extension portion 12b, which is located farthest from the second electrode main body 10b in the direction opposite to the first direction D1, is located in the direction opposite to the first direction D1 with respect to the end of the first electrode main body 10a in the first direction D1. The first intruding portion 14a of the first receiving electrode Rx3 and the second intruding portion 14b of the second receiving electrode Rx4 face each other in the first direction D1.

[0068] The second intruding portion 14b extends along the outline of the first electrode body 10a of the first receiving electrode Rx3. The farthest portion of the second intruding portion 14b in the direction opposite to the first direction D1 is a second farthest portion 19b of the second extending portion 12b in the direction opposite to the first direction D1.

[0069] As shown in Figure 7, in the first electrode body 10a and the second electrode body 10b that are adjacent to each other, the first expansion portion 12a of the first electrode body 10a is configured so that the first penetration portion 14a of the first expansion portion 12a penetrates into the second node N2 on the side where the second electrode body 10b is located and is insulated from the second electrode body 10b.

[0070] The first intruding portion 14a of the first electrode main body 10a is arranged so that the portion that intrudes into the second node N2 on the side where the second electrode main body 10b is located (i.e., the portion of the first intruding portion 14a shown in FIG. 7 that is hatched with dots) does not overlap with the cells 11b, 11b at the second node N2. Specifically, the first intruding portion 14a of the first electrode main body 10a is arranged so that the portion that intrudes into the second node N2 on the side where the second electrode main body 10b is located is spaced apart from the cell 11b located at the second node N2 in the first direction D1.

[0071] The first intruding portion 14a of the first electrode main body 10a extends in a direction parallel to the outline of the cell 11b located at the second node N2 on the second electrode main body 10b side. Furthermore, in the first intruding portion 14a of the first electrode main body 10a, a corner located midway through the first intruding portion 14a (first farthest portion 19a shown in FIG. 7) faces in the first direction D1 a portion corresponding to the joint between the cells 11b, 11b at the second node N2 on the second electrode main body 10b side.

[0072] 7 , the first intruding portion 14a of the first receiving electrode Rx3 extends in a direction parallel to the outline of the cell 11b located at the second node N2. The first intruding portion 14a of the first receiving electrode Rx3 is disposed such that the portion of the first intruding portion 14a that intrudes into the second node N2 on the second receiving electrode Rx4 side is spaced apart in the first direction D1 from the cell 11b located at the second node N2. Furthermore, a corner (first farthest portion 19a shown in FIG. 7 ) located midway through the first intruding portion 14a of the first receiving electrode Rx3 faces, in the first direction D1, a portion of the second node N2 on the second receiving electrode Rx4 side that corresponds to the joint between the cells 11b.

[0073] Next, as shown in FIGS. 7 and 8, the first complementary portion 15a of the first receiving electrode Rx3 branches off from the first intruding portion 14a in a direction different from that of the first intruding portion 14a.

[0074] The first complementary portion 15a extends obliquely with respect to both the first direction D1 and the second direction D2. The first complementary portion 15a is located between the first electrode body 10a of the first receiving electrode Rx3 and the second electrode body 10b of the second receiving electrode Rx4 (see FIG. 7). Note that the first complementary portion 15a is configured so that most of it does not extend into the first node N1 on the first electrode body 10a side of the adjacent first and second electrode bodies 10a, 10b.

[0075] As shown in FIGS. 7 and 9, the first complementary portion 15b of the second receiving electrode Rx4 branches off from the second intruding portion 14b in a direction different from that of the second intruding portion 14b.

[0076] The first complementary portion 15b extends obliquely with respect to both the first direction D1 and the second direction D2. The first complementary portion 15b is located between the first electrode body 10a of the first receiving electrode Rx3 and the second electrode body 10b of the second receiving electrode Rx4 (see FIG. 7). Note that the first complementary portion 15b is configured so that most of it does not extend into the second node N2 on the second electrode body 10b side of the adjacent second electrode body 10b and first electrode body 10a.

[0077] 7, in the first electrode body 10a and the second electrode body 10b adjacent to each other, the first expansion portion 12a of the first electrode body 10a and the second expansion portion 12b of the second electrode body 10b face each other in the first direction D1. The first complementary portion 15a included in the first expansion portion 12a and the first complementary portion 15b included in the second expansion portion 12b extend in directions parallel to each other and are spaced apart in a direction perpendicular to the respective extension directions.

[0078] (Cross-sectional structure of thin wire) Each thin wire 20 includes a conductive material buried in each groove 6. As shown in Fig. 10 , each thin wire 20 is composed of an adhesion layer 21, a seed layer 22, a conductive layer 23, and a blackening layer 24.

[0079] The adhesion layer 21 is an element for ensuring adhesion of the seed layer 22 to the groove portion 6. The adhesion layer 21 has the function of making the thin wires 20 less visible when viewed by a user from the operation surface 2b side.

[0080] The adhesion layer 21 is a metal layer made of, for example, a metal nitride or metal oxide containing at least one metal selected from the group consisting of Ti, Al, V, W, Ta, Si, Cr, Ag, Mo, Cu, and Zn. The adhesion layer 21 may be a single layer or a laminate of multiple layers with different compositions. The adhesion layer 21 is disposed in the form of a thin film on the groove portion 6 by, for example, vapor deposition or sputtering.

[0081] 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 in the form of a thin film on the adhesion layer 21 by, for example, vapor deposition or sputtering.

[0082] The conductive layer 23 is formed by, for example, electroplating. When electroplating is performed, the seed layer 22 and the conductive layer 23 are formed integrally. As a result, the interface between the seed layer 22 and the conductive layer 23 becomes indistinguishable.

[0083] The blackened layer 24 is laminated on the surface of the conductive layer 23. The blackened 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 blackened layer 24 is, for example, 7 nm or more and 10 nm or less. The blackened layer 24 has the function of making the thin wires 20 less visible when viewed from the operation surface 2b side by a user.

[0084] [Effects of the Embodiment] As described above, the first extension portion 12a of the first receiving electrode Rx3 is spaced from the second electrode main body 10b, and the first farthest portion 19a of the first extension portion 12a, which is located farthest from the first electrode main body 10a in the first direction D1, is positioned further in the first direction D1 than the end of the second electrode main body 10b in the direction opposite to the first direction D1. As a result, the touch sensitivity is not concentrated on the second node N2 on the side where the second electrode main body 10b is located, but is distributed toward the first node N2 on the side where the first electrode main body 10a is located. In other words, the touch sensitivity is not concentrated on the second node N2 on the side where the second electrode main body 10b is located, but is distributed toward the first node N1 on the side where the first electrode main body 10a is located. As a result, in the touch sensor 1, bias in touch sensitivity at a specific node N is eliminated, unlike the configuration of the prior art (e.g., the configuration disclosed in Patent Document 1 mentioned above). The touch sensitivity is calculated as the capacitance value absorbed by the object to be detected (e.g., the user's finger) divided by the capacitance value between the electrode main body 10 and the extension portion 12 and the transmitting electrode Tx.

[0085] For example, suppose a detection object touches the second node N2 between the transmitting electrode Tx3 and the main area Ma of the second receiving electrode Rx4 at a position including the second electrode main body 10b located at the second node N2 and the first intrusion portion 14a of the first receiving electrode Rx3 (see reference symbol Tp in FIGS. 3 and 7 ). In this case, touch sensitivity is not concentrated only at the second electrode main body 10b located at the second node N2 between the transmitting electrode Tx3 and the main area Ma of the second receiving electrode Rx4. Specifically, the touch sensitivity is dispersed toward the first node N1 between the transmitting electrode Tx3 and the main area Ma of the first receiving electrode Rx3 via the first intrusion portion 14a (first extension portion 12a) of the first receiving electrode Rx3. This enables accurate and appropriate detection using multiple receiving electrodes Rx so that the position of the touch operation by the detection object (hereinafter simply referred to as the "touch position") corresponds to the actual touch position. As a result, the touch sensor 1 improves the detection accuracy of the touch position.

[0086] When the detection accuracy of the touch position is improved, for example, continuous touch actions in which the detection target moves linearly or curvedly can be accurately and appropriately detected using the multiple receiving electrodes Rx. As a result, the touch sensor 1 provides good operability and drawing performance for user touch actions (especially the continuous touch actions). Specifically, the actual trajectory (e.g., handwriting) of the continuous touch actions matches the detection result of the continuous touch actions (e.g., characters displayed on the screen of a display device connected to the touch sensor 1). Furthermore, even if the touch sensor 1 is enlarged, the characteristic configuration according to the embodiment of the present disclosure described above allows the actual trajectory of the continuous touch actions to match the detection result of the continuous touch actions. In other words, even if the touch sensor 1 is enlarged, good operability and drawing performance can be achieved.

[0087] Therefore, the touch sensor 1 according to the embodiment of the present disclosure can accurately and appropriately detect a touch action of a detection target.

[0088] The first extension portion 12a also includes a first intruding portion 14a extending along the outline of the second electrode main body 10b of the second receiving electrode Rx4, and the farthest portion of the first intruding portion 14a in the first direction D1 is a first farthest portion 19a in the first direction D1 of the first extension portion 12a. This first intruding portion 14a makes it possible to maintain insulation between the first intruding portion 14a provided on the first electrode main body 10a and the second electrode main body 10b, while allowing most of the first intruding portion 14a to intrude into the second node N2 on the second electrode main body 10b side. This makes it possible to eliminate bias in touch sensitivity at a specific node N.

[0089] The first extension portion 12a further includes a first connecting portion 13a that connects the first electrode main body 10a of the first receiving electrode Rx3 and the first intruding portion 14a. This first connecting portion 13a makes it possible to adjust the first intruding portion 14a of the first extension portion 12a provided on the first electrode main body 10a so that it intrudes into the second node N2 on the second electrode main body 10b side in accordance with the interval between the adjacent first electrode main body 10a and second electrode main body 10b (specifically, the pitch EP between the main areas Ma, Ma).

[0090] The first connecting portion 13a extends in a zigzag pattern, which allows the distance from the first electrode body 10a to the first expanding portion 12a to be adjusted in accordance with the interval between the adjacent first electrode body 10a and second electrode body 10b (specifically, the pitch EP between the main areas Ma, Ma).

[0091] The first extension portion 12a of the first receiving electrode Rx3 further includes a first complementary portion 15a branching from the first intrusive portion 14a in a direction different from that of the first intrusive portion 14a. The first complementary portion 15a is located between the first electrode main body 10a of the first receiving electrode Rx3 and the second electrode main body 10b of the second receiving electrode Rx4. This first complementary portion 15a can complement the detection accuracy of a touch position between the first node N1 on the first electrode main body 10a side and the second node N2 on the second electrode main body 10b side. In other words, the first complementary portion 15a can improve the detection accuracy of a touch position at positions other than the first node N1 and the second node N2.

[0092] The second receiving electrode Rx4 further includes a second extension portion 12b located between the first electrode body 10a and the second electrode body 10b and extending from the second electrode body 10b. The second extension portion 12b of the second receiving electrode Rx4 is spaced apart from the first electrode body 10a, and a second farthest portion 19b of the second extension portion 12b, which is located farthest from the second electrode body 10b in the direction opposite to the first direction D1, is located in the direction opposite to the first direction D1 with respect to the end of the first electrode body 10a in the first direction D1. This eliminates any imbalance in touch sensitivity between the adjacent first electrode body 10a and second electrode body 10b. As a result, touching of a detection object can be accurately and appropriately detected.

[0093] [First Modification of the Embodiment] In the above embodiment, a first complementary portion 15a branching from the first intruding portion 14a in a direction different from the first intruding portion 14a is provided, but this is not limited to this. For example, as in the first modification shown in Figures 11 and 12, a second complementary portion 16a may be provided instead of the first complementary portion 15a. Specifically, in Figure 12, the first extension portion 12a of the first receiving electrode Rx3 has a second complementary portion 16a. Furthermore, the second extension portion 12b of the second receiving electrode Rx4 has a second complementary portion 16b.

[0094] 11 and 12 , in the touch sensor 1 according to the first modification, unlike the above embodiment, the pitch EP between the main areas Ma, Ma is larger than the width dimension EW2 of the main areas Ma. Therefore, in the first modification, the distance from the first electrode body 10a to the first intruding portion 14a is relatively longer than in the above embodiment. That is, the length of the first connecting portion 13a in this modification in the first direction D1 is longer than that of the first connecting portion 13a shown in the above embodiment.

[0095] In this modification, even if a first complementary portion 15a (not shown in FIGS. 11 and 12) branching from the first intruding portion 14a is provided, it may not be sufficient to complement the detection accuracy of the touch position between the first node N1 on the first electrode main body 10a side and the second node N2 on the second electrode main body 10b side. For this reason, the touch sensor 1 according to modification 1 is provided with a second complementary portion 16a instead of the first complementary portion 15a.

[0096] The second complementary portion 16a of the first receiving electrode Rx3 branches off from the first connecting portion 13a in a direction different from that of the first connecting portion 13a. In this modification, the second complementary portion 16a extends obliquely with respect to both the first direction D1 and the second direction D2 from approximately the center of the first connecting portion 13a in the first direction D1. The second complementary portion 16a is located between the first electrode body 10a of the first receiving electrode Rx3 and the second electrode body 10b of the second receiving electrode Rx4 (see FIG. 12 ).

[0097] The second complementary portion 16b of the second receiving electrode Rx4 branches off from the second intruding portion 14b in a direction different from that of the second intruding portion 14b. The second complementary portion 16b is located between the first electrode body 10a of the first receiving electrode Rx3 and the second electrode body 10b of the second receiving electrode Rx4 (see FIG. 12).

[0098] In this modification, even if the pitch EP between the main areas Ma is greater than the width EW2 of the main areas Ma, the second complementary portion 16a can be easily disposed at the intermediate position between the adjacent main areas Ma in the first direction D1. As a result, it is possible to complement the detection accuracy of the touch position between the first node N1 on the first electrode main body 10a side and the second node N2 on the second electrode main body 10b side. The second complementary portion 16b can also achieve the same effects as the second complementary portion 16a.

[0099] [Second Modification of the Embodiment] In the above embodiment, the first connecting portion 13a extends in a zigzag pattern, but this is not limited to this. For example, as in the second modification shown in Figures 13 and 14, the first connecting portion 13a may extend linearly along the first direction D1. Even with this configuration, the distance from the first electrode main body 10a to the first intruding portion 14a can be adjusted depending on the interval between the adjacent first electrode main body 10a and second electrode main body 10b (specifically, the pitch EP between the main areas Ma, Ma).

[0100] Here, in Modification 2, as in Modification 1 described above, the pitch EP between the main areas Ma, Ma is larger than the width dimension EW2 of the main areas Ma. Therefore, in Modification 2, as in Modification 1, second complementary portions 16a and 16b are provided. Note that the specific configurations and effects of the second complementary portions 16a and 16b are the same as those in Modification 1 described above, and therefore detailed description thereof will be omitted.

[0101] [Other Embodiments] In the above embodiment, the view area Va has a substantially rectangular shape, but is not limited to this. The view area Va may have a polygonal shape such as a substantially circular shape or a pentagonal shape in plan view.

[0102] In the above embodiment, a configuration using one substrate 3 is shown, but this is not limiting. That is, a configuration using two substrates 3 (not shown) may also be used. Although not shown, two substrates 3 may be used in which the second layer 5 is stacked on the front or back surface of the first layer 4.

[0103] In the above embodiment, the substrate 3 has the first layer 4 and the second layer 5, but is not limited to this. For example, the substrate 3 may have only the first layer 4. In such a configuration, it is sufficient that the plurality of grooves 6 are formed on at least one of the front and back surfaces of the first layer 4.

[0104] In the above embodiment, the direction from the left side to the right side on the paper surface of Fig. 3 is defined as the first direction D1, and the direction from the bottom side to the top side on the paper surface of Fig. 3 is defined as the second direction D2, but this is not limited to this. For example, the direction from the bottom side to the top side on the paper surface of Fig. 3 may be defined as the first direction D1, and the direction from the left side to the right side on the paper surface of Fig. 3 may be defined as the second direction D2.

[0105] In the above embodiment, a configuration in which a plurality of transmitting electrodes Tx are provided on the rear surface side of the substrate 3 while a plurality of receiving electrodes Rx are provided on the front surface side of the substrate 3 has been described, but this configuration is not limiting. For example, although not shown, a configuration in which a plurality of transmitting electrodes Tx are provided on the front surface side of the substrate 3 while a plurality of receiving electrodes Rx are provided on the rear surface side of the substrate 3 may be used. Note that even in such a configuration, a dummy pattern and dummy electrodes (not shown) are disposed on the front surface side of the substrate 3 (the visible side of the touch sensor 1).

[0106] In the above embodiment, 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 substrate 3, but this is not limiting. That is, the concept of the touch sensor 1 according to the present disclosure includes a state before the cover member 2, the flexible wiring board 8, etc. are attached to the substrate 3. Furthermore, the concept of the touch sensor 1 according to the present disclosure also includes a configuration in which the above-described plurality of transmitting electrodes Tx and plurality of receiving electrodes Rx are formed on a long base material (for example, a long hoop-shaped member not shown) in a state before the substrates 3 are individually formed.

[0107] In the above embodiment, the shape of each cell 11 is a diamond, but the shape is not limited to this. That is, each cell 11 may have a quadrilateral shape formed by an imaginary first diagonal line DL1 and an imaginary second diagonal line DL2 that is longer than the first diagonal line DL1.

[0108] In the above embodiment, the transmitting electrodes Tx do not include a dummy pattern, but the present invention is not limited to this. That is, the transmitting electrodes Tx may include a dummy pattern (not shown).

[0109] In the above embodiment, a configuration in which no dummy electrodes are provided between the transmitting electrodes Tx has been described, but this is not limiting. For example, when the electrode width EW1 of the transmitting electrodes Tx is relatively small, dummy electrodes (not shown) may be provided between the transmitting electrodes Tx, Tx.

[0110] In the above embodiment, the plating solution contains copper (Cu) as a main component, but this is not limiting. For example, the plating solution may contain silver, gold, or a copper alloy.

[0111] In the above embodiment, the extension portion 12 includes the connecting portion 13, but this is not limiting. For example, in comparison with the above embodiment, if the pitch EP between the main areas Ma, Ma is extremely small, the connecting portion 13 may be omitted. That is, the intruding portion 14 may be provided directly in each cell 11 of the electrode body 10.

[0112] In the above embodiment, the first extension portion 12a includes the first complementary portion 15a, but this is not limited to this. In other words, compared to the above embodiment, if the pitch EP between the main areas Ma, Ma is extremely small, it may not be necessary to complement the detection accuracy of the touch position between the first node N1 on the first electrode main body 10a side and the second node Nb on the second electrode main body 10b side. In such a case, the first complementary portion 15a may not be particularly provided. The same applies to the first complementary portion 15b of the second extension portion 12b.

[0113] The present disclosure is industrially applicable as a touch sensor.

[0114] 1: Touch sensor 2: Cover member 2a: Decorative portion 2b: Operation surface 3: Substrate 3a: First surface 3b: Second surface 4: First layer 5: Second layer 6: Groove portion 7: Adhesive layer 8: Flexible wiring board 10: Electrode body 10a: First electrode body 10b: Second electrode body 11: Cell 12: Extension portion 12a: First extension portion 12b: Second extension portion 13: Connecting portion 13a: First connecting portion 13b: Second connecting portion 14: Penetration portion 14a: First penetration portion 14b: Second penetration portion 15a, 15b: First complementary portion 16a, 16b: Second complementary portion 19a: First furthest portion 19b: Second furthest portion 20: Thin wire 20a: First thin wire 20b: Second thin wire 21: Adhesion layer 22: Conductive layer 23: plating layer 24: blackened layer Tx: transmitting electrode Rx: receiving electrode Ma: main area N1: first node N2: second node

Claims

1. A touch sensor comprising: a transmitting electrode extending along a first direction; a first receiving electrode formed by a first thin wire, the first electrode body extending along a second direction perpendicular to the first direction and intersecting with the transmitting electrode in a planar view; and a second receiving electrode formed by a second thin wire, the second electrode body extending along the second direction and intersecting with the transmitting electrode in a planar view, the first receiving electrode being located in a first direction of the first receiving electrode, the first receiving electrode further having a first extension portion located between the first electrode body and the second electrode body and extending from the first electrode body, the first extension portion of the first receiving electrode being spaced apart from the second electrode body, and a first farthest portion of the first extension portion which is located furthest from the first electrode body in the first direction is located in the first direction further than an end of the second electrode body in a direction opposite to the first direction.

2. A touch sensor as described in claim 1, wherein the first extension portion includes a first penetration portion extending along an outline of the second electrode body of the second receiving electrode, and the furthest portion of the first penetration portion in the first direction is the first furthest portion of the first extension portion in the first direction.

3. A touch sensor according to claim 1, wherein the first extension portion further includes a first connection portion connecting the first electrode body of the first receiving electrode and the first penetration portion.

4. The touch sensor according to claim 3, wherein the first connecting portion extends in a zigzag pattern.

5. The touch sensor according to claim 3, wherein the first connecting portion extends linearly along the first direction.

6. A touch sensor as described in claim 2, wherein the first extension portion of the first receiving electrode further has a first complementary portion branching off from the first penetration portion in a direction different from that of the first penetration portion, and the first complementary portion is located between the first electrode body of the first receiving electrode and the second electrode body of the second receiving electrode.

7. A touch sensor as described in claim 3, wherein the first extension portion of the first receiving electrode further has a second complementary portion branching off from the first connecting portion in a direction different from the first connecting portion, and the second complementary portion is located between the first electrode body of the first receiving electrode and the second electrode body of the second receiving electrode.

8. A touch sensor as described in claim 1, wherein the second receiving electrode further has an extension portion located between the first electrode body and the second electrode body and extending from the second electrode body, the second extension portion of the second receiving electrode is spaced apart from the first electrode body, and a second furthest portion of the second extension portion located furthest from the second electrode body in the direction opposite to the first direction is located in the direction opposite to the first direction further than the end of the first electrode body in the first direction.

9. A touch sensor according to claim 8, wherein the first intrusion portion of the first receiving electrode and the second intrusion portion of the second receiving electrode face each other in the first direction.

10. A touch sensor as described in claim 1, wherein the first receiving electrode forms a first node generating a capacitance in a region where it intersects with the transmitting electrode, the second receiving electrode forms a second node generating a capacitance in a region where it intersects with the transmitting electrode, and a portion of the first extension portion overlaps with the second node in a planar view.

11. A touch sensor as described in claim 1, further comprising a substrate, the transmitting electrode being disposed on a first surface of the substrate, the first receiving electrode being disposed on a second surface of the substrate opposite the first surface, and the second receiving electrode being disposed on the second surface of the substrate.