Input device and control method thereof

Abstract

To provide an input device that improves the accuracy of information relating to a force received from an operating object.SOLUTION: An input device ID includes an operation unit OU and a control unit CU. The operation unit OU includes a piezoelectric element 10 that receives force from an operating object. The piezoelectric element 10 includes one piezoelectric body that includes a first portion that is displaced by application of a voltage and a second portion that generates an electric charge due to the displacement. The operation unit OU outputs a signal according to the electric charge generated in the second portion. The control unit CU acquires information regarding the force received from the operating object based on the signal output from the operation unit OU.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an input device and a control method for an input device. [Background technology]

[0002] A known input device includes an operation unit. The operation unit includes a housing that receives a force from an operating object and a plurality of piezoelectric elements that are spaced apart from one another within the housing. In this input device, a voltage is applied to one of the plurality of piezoelectric elements. The operation unit outputs a signal corresponding to an electric charge generated in the piezoelectric element to which no voltage is applied. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-57297 Summary of the Invention [Problem to be solved by the invention]

[0004] In the input device described above, applying a voltage to one of the multiple piezoelectric elements displaces that piezoelectric element. The displacement of the piezoelectric element to which voltage is applied is transmitted via the housing to the piezoelectric elements to which no voltage is applied. Hereinafter, the piezoelectric element to which voltage is applied may be referred to as the "first piezoelectric element," and the piezoelectric element to which no voltage is applied may be referred to as the "second piezoelectric element." When the housing receives a force from the operating object, a restraining force corresponding to the force acts on the housing. Therefore, the ease of transmission of the displacement between the first and second piezoelectric elements via the housing changes depending on the force received from the operating object. This causes the displacement of the second piezoelectric element to change depending on the force received from the operating object. When the displacement of the second piezoelectric element changes, the charge generated in the second piezoelectric element also changes. In the input device described above, information about the force received from the operating object is acquired by utilizing the fact that the ease of transmission of the displacement between the first and second piezoelectric elements via the housing changes depending on the force received from the operating object. On the other hand, in the above-described input device, the displacement of the first piezoelectric element is transmitted to the second piezoelectric element via the housing, so there is room for improvement in terms of the accuracy of information relating to the force received from the operating object.

[0005] An object of one aspect of the present invention is to provide an input device that improves the accuracy of information relating to a force received from an operating object. Another aspect of the present invention aims to provide an input device that improves the accuracy of information relating to a force applied from an operating object. [Means for solving the problem]

[0006] An input device according to one aspect includes an operation unit and a control unit. The operation unit includes a piezoelectric element that receives a force from an operating object, the piezoelectric element including a piezoelectric body that includes a first portion that is displaced by application of a voltage and a second portion that generates an electric charge due to the displacement, and outputs a signal according to the electric charge generated in the second portion. The control unit acquires information regarding the force received from the operating object based on the signal output from the operation unit.

[0007] In one of the above aspects, the operation unit includes a piezoelectric element that receives force from an operating body, the piezoelectric element including a single piezoelectric body that includes a first portion that displaces upon application of a voltage and a second portion that generates an electric charge upon displacement. When the first portion of the single piezoelectric body is displaced, the displacement of the first portion is transmitted to the second portion, causing the second portion to be displaced. When the piezoelectric element receives force from the operating body, a restraining force corresponding to the force acts on the single piezoelectric body including the first and second portions. Therefore, the ease of displacement of the second portion changes depending on the force the piezoelectric element receives from the operating body. In other words, when the piezoelectric element receives force from the operating body, the displacement of the second portion changes depending on the force. As the displacement of the second portion changes, the electric charge generated in the second portion also changes. Thus, in the above-described one aspect, the second part is displaced by the transmission of the displacement of the first part, and the displacement of the second part changes in response to the force received from the operating body. Here, if the displacement of the first part is not properly transmitted to the second part, the displacement of the second part may not change in response to the force received from the operating body. In other words, the ease with which the displacement is transmitted between the first part and the second part affects the accuracy of the information regarding the force received from the operating body. In the above-described one aspect, because the first part and the second part are included in a single piezoelectric body, the displacement of the first part is more easily transmitted to the second part than when the first part and the second part are included in separate piezoelectric bodies. As described above, the above-described one aspect improves the accuracy of information relating to the force received from the operating object.

[0008] In another aspect, there is provided a control method for an input device, the input device including a piezoelectric element that receives a force from an operating object, the piezoelectric element including one piezoelectric body including a first portion that is displaced by application of a voltage and a second portion that generates an electric charge by the displacement, and an operation unit that outputs a signal according to the electric charge generated in the second portion. The control method for an input device according to the above-mentioned another aspect includes applying a voltage to the first portion, acquiring a signal output from the operation unit, and acquiring information regarding the force received from the operating object based on the acquired signal.

[0009] In the above-described another aspect, a voltage is applied to the first portion. When the voltage is applied to the first portion, the first portion is displaced. This causes the displacement of the first portion to be transmitted to the second portion, resulting in a change in the second portion. When the piezoelectric element receives a force from the operating body, a restraining force corresponding to the force acts on the single piezoelectric body including the first portion and the second portion. Therefore, the ease of displacement of the second portion changes depending on the force the piezoelectric element receives from the operating body. In other words, when the piezoelectric element receives a force from the operating body, the displacement of the second portion changes depending on the force. As the displacement of the second portion changes, the charge generated in the second portion also changes. In another aspect of the above, a voltage is applied to the first part, which is included together with the second part in one piezoelectric body, so that the displacement of the first part due to the application of a voltage is more easily transmitted to the second part than when the first part and the second part are included in separate piezoelectric bodies. As described above, the above-described one aspect improves the accuracy of information relating to the force received from the operating object. [Effects of the Invention]

[0010] According to one aspect of the present invention, there is provided an input device that improves the accuracy of information relating to a force received from an operating object. According to another aspect of the present invention, there is provided a control method for an input device that improves the accuracy of information relating to a force received from an operating object. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a block diagram of an input device according to an embodiment. [Figure 2] FIG. 2 is a perspective view showing a piezoelectric element. [Figure 3] FIG. 3 is an exploded perspective view of the piezoelectric element. [Figure 4] FIG. 4 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 5] FIG. 5 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 6] FIG. 6 is a circuit diagram showing an example of the input device according to this embodiment. [Figure 7]FIG. 7 is a diagram illustrating an example of a control process in the input device. [Figure 8] FIG. 8 is a diagram illustrating an example of a control process in the input device. [Figure 9] FIG. 9 is an exploded perspective view of the piezoelectric element. [Figure 10] FIG. 10 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 11] FIG. 11 is a perspective view of a piezoelectric element. [Figure 12] FIG. 12 is an exploded perspective view of the piezoelectric element. [Figure 13] FIG. 13 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 14] FIG. 14 is a perspective view of a piezoelectric element. [Figure 15] FIG. 15 is an exploded perspective view of the piezoelectric element. [Figure 16] FIG. 16 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 17] FIG. 17 is a perspective view of a piezoelectric element. [Figure 18] FIG. 18 is an exploded perspective view of the piezoelectric element. [Figure 19] FIG. 19 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 20] FIG. 20 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 21] FIG. 21 is a perspective view of a piezoelectric element. [Figure 22] FIG. 22 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 23] FIG. 23 is a perspective view of a piezoelectric element. [Figure 24] FIG. 24 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 25] FIG. 25 is a perspective view of a piezoelectric element. [Figure 26] FIG. 26 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 27] FIG. 27 is a diagram showing a cross-sectional configuration of a piezoelectric element. [Figure 28]FIG. 28 is a flowchart showing an example of a control process in the input device. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. In the description, the same elements or elements having the same functions will be denoted by the same reference numerals, and redundant description will be omitted.

[0013] The configuration of the input device ID according to this embodiment will be described with reference to Figs. 1 to 6. Fig. 1 is a block diagram of the input device according to this embodiment. Fig. 2 is a perspective view showing a piezoelectric element. Fig. 3 is an exploded perspective view of the piezoelectric element. Figs. 4 and 5 are views showing the cross-sectional configuration of the piezoelectric element. Fig. 6 is a circuit diagram showing an example of the input device according to this embodiment. Hatching is omitted in Figs. 4 and 5 to clearly show each part. As shown in Fig. 1, the input device ID includes an operation unit OU and a control unit CU. The operation unit OU includes a piezoelectric element 10 and an amplifier 20.

[0014] In the input device ID, the piezoelectric element 10 receives a force from an operating object. The operating object includes, for example, a part of a living body, an object covering a part of a living body, or an object held by the living body. The part of a living body includes, for example, a fingertip of a human body. The object covering a part of a living body includes, for example, a glove worn on a human hand. The object held by the living body includes, for example, an operating member.

[0015] As shown in FIGS. 2 to 5, the piezoelectric element 10 includes one piezoelectric body 11, an internal electrode 12, and an external electrode 13. In this embodiment, the piezoelectric body 11 has a rectangular parallelepiped shape. Examples of the rectangular parallelepiped shape include a rectangular parallelepiped shape with chamfered corners and ridges, and a rectangular parallelepiped shape with rounded corners and ridges. The piezoelectric body 11 includes a pair of principal surfaces 11a and 11b, a pair of side surfaces 11c and 11d, and a pair of end surfaces 11e and 11f. The pair of principal surfaces 11a and 11b face each other in a first direction D1. The pair of side surfaces 11c and 11d face each other in a second direction D2. The pair of end surfaces 11e and 11f face each other in a third direction D3. The second direction D2 intersects with the first direction D1. The third direction D3 intersects with the first direction D1 and the second direction D2. In this embodiment, the first direction D1, the second direction D2, and the third direction D3 are perpendicular to one another. The main surfaces 11a and 11b, the side surfaces 11c and 11d, and the end surfaces 11e and 11f are, for example, rectangular. The rectangular shape includes, for example, a shape with chamfered corners and a shape with rounded corners.

[0016] The pair of principal surfaces 11a, 11b connect the side surface 11c and the side surface 11d and extend in the second direction D2. The pair of principal surfaces 11a, 11b connect the end surface 11e and the end surface 11f and extend in the third direction D3. The pair of side surfaces 11c, 11d connect the principal surface 11a and the principal surface 11b and extend in the first direction D1. The pair of side surfaces 11c, 11d connect the end surface 11e and the end surface 11f and extend in the third direction D3. The pair of end surfaces 11e, 11f connect the principal surface 11a and the principal surface 11b and extend in the first direction D1. The pair of end surfaces 11e, 11f connect the side surface 11c and the side surface 11d and extend in the second direction D2.

[0017] As shown in FIG. 3, in this embodiment, the piezoelectric body 11 includes at least a plurality of piezoelectric layers 14a, 14b, 14c, 14d, 14e, and 14f. The piezoelectric body 11 is formed, for example, by stacking a plurality of piezoelectric layers 14a to 14f. In this embodiment, the piezoelectric layers 14a to 14f are arranged in this order in the first direction D1. In this embodiment, the main surface 11a of the piezoelectric body 11 includes the outer surface of the piezoelectric layer 14a. The piezoelectric body 11 also includes one or more piezoelectric layers positioned between the plurality of piezoelectric layers 14a to 14f. Each of the piezoelectric layers 14a to 14f constitutes a part of the piezoelectric body 11. The direction in which the plurality of piezoelectric layers 14a to 14f are stacked is, for example, the first direction D1. In this embodiment, each of the piezoelectric layers 14a, 14b, 14c, 14d, 14e, and 14f has a rectangular shape when viewed from the first direction D1. The plurality of piezoelectric layers 14a-14f includes a piezoelectric ceramic material. That is, the piezoelectric body 11 includes a piezoelectric ceramic material. Examples of the piezoelectric ceramic material include PZT [Pb(Zr,Ti)O3], PT(PbTiO3), PLZT [(Pb,La)(Zr,Ti)O3], and barium titanate (BaTiO3). The plurality of piezoelectric layers 14a-14f are formed from sintered ceramic green sheets containing the above-mentioned piezoelectric ceramic material. The plurality of piezoelectric layers 14a-14f are integrated to the extent that the boundaries between them are practically invisible.

[0018] The internal electrode 12 is disposed within the piezoelectric body 11. The internal electrode 12 includes a conductive material. The conductive material includes, for example, Ag / Pd, Pt, Pd, or Cu. The internal electrode 12 is formed as a sintered body of a conductive paste including the conductive material. In this embodiment, the internal electrodes 12 include a pair of internal electrodes 12A and 12B, a pair of internal electrodes 12C and 12D, a plurality of internal electrodes 12E, a pair of internal electrodes 12F and 12G, and a pair of internal electrodes 12H and 121. That is, in this embodiment, the piezoelectric element 10 includes a plurality of internal electrodes 12A, 12B, 12C, 12D, 12E, 12F, 12G, 12H, and 121.

[0019] The pair of internal electrodes 12A, 12B and the pair of internal electrodes 12C, 12D are disposed on the piezoelectric layer 14b and the piezoelectric layer 14f, respectively. That is, the pair of internal electrodes 12A, 12B and the pair of internal electrodes 12C, 12D are located on the same layer. The internal electrodes 12A and 12B are arranged, for example, at one diagonal corner of the rectangular shape of the piezoelectric body 11. When viewed from the first direction D1, the one diagonal corner includes a corner formed by the side surface 11d and the end surface 11e and a corner formed by the side surface 11c and the end surface 11f. In this embodiment, the internal electrode 12A is arranged at the corner formed by the side surface 11d and the end surface 11e, and the internal electrode 12B is arranged at the corner formed by the side surface 11c and the end surface 11f. The internal electrodes 12C and 12D are arranged, for example, at the other diagonal corner of the rectangular shape of the piezoelectric body 11. When viewed from the first direction D1, the other diagonal corner includes a corner formed by the side surface 11d and the end surface 11f and a corner formed by the side surface 11c and the end surface 11e. In this embodiment, the internal electrode 12C is arranged at the corner formed by the side surface 11d and the end surface 11f, and the internal electrode 12D is arranged at the corner formed by the side surface 11c and the end surface 11e.

[0020] In the piezoelectric layers 14b and 14f, the internal electrodes 12A and 12C are adjacent to the side surface 11d, and the internal electrodes 12B and 12D are adjacent to the side surface 11c. In this embodiment, the internal electrodes 12A and 12B are physically and electrically connected by a connecting portion 15a. The connecting portion 15a extends, for example, in the diagonal direction of the one diagonal.

[0021] The internal electrode 12E is disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. The internal electrode 12E has, for example, a rectangular shape. In this embodiment, the internal electrode 12E has a rectangular shape that is slightly smaller than the rectangular shape of the piezoelectric body 11 when viewed from the first direction D1. In this embodiment, the internal electrode 12E includes an internal electrode 12Ea and an internal electrode 12Eb. When viewed from the first direction D1, the internal electrode 12Ea is disposed closer to the end face 11e than the center of the piezoelectric layers 14c and 14e in the third direction D3. When viewed from the first direction D1, the internal electrode 12Eb is disposed closer to the end face 11f than the center of the piezoelectric layers 14c and 14e in the third direction D3. In this embodiment, the internal electrodes 12Ea and 12Eb are integral.

[0022] The pair of internal electrodes 12F, 12G and the pair of internal electrodes 12H, 12I are disposed on the piezoelectric layer 14d. That is, the pair of internal electrodes 12F, 12G and the pair of internal electrodes 12H, 12I are located on the same layer. The internal electrodes 12F and 12G are arranged, for example, at one diagonal corner of the rectangular shape of the piezoelectric body 11. In this embodiment, the internal electrode 12F is arranged at the corner formed by the side surface 11d and the end surface 11e, and the internal electrode 12G is arranged at the corner formed by the side surface 11c and the end surface 11f. The internal electrodes 12H and 12I are arranged, for example, at the other diagonal corner of the rectangular shape of the piezoelectric layer 14c. In this embodiment, the internal electrode 12H is arranged at the corner formed by the side surface 11d and the end surface 11f, and the internal electrode 12I is arranged at the corner formed by the side surface 11c and the end surface 11e.

[0023] In the piezoelectric layer 14d, the internal electrodes 12F and 12H are adjacent to the side surface 11d, and the internal electrodes 12G and 12I are adjacent to the side surface 11c. In this embodiment, the internal electrodes 12H and 12I are physically and electrically connected by a connecting portion 15b. The connecting portion 15b extends, for example, in the diagonal direction of the other diagonal.

[0024] In this embodiment, the piezoelectric body 11 includes connecting conductors 16a, 16b, 16c, 16d, 16e1, 16e2, 16f, 16g, 16h, and 16i. The connecting conductors 16a, 16c, 16e1, 16f, and 16h are exposed on the side surface 11d. The connecting conductors 16b, 16d, 16e2, 16g, and 16i are exposed on the side surface 11c.

[0025] The connecting conductors 16a, 16b, 16c, and 16d are disposed on the piezoelectric layer 14b and the piezoelectric layer 14f. In the piezoelectric layer 14b and the piezoelectric layer 14f, the connecting conductors 16a and 16c are exposed on the side surface 11d at different positions in the third direction D3, for example. The connecting conductors 16b and 16d are exposed on the side surface 11c at different positions in the third direction D3, for example. The connecting conductors 16a and 16d are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example. The connecting conductors 16b and 16c are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example.

[0026] In the piezoelectric layers 14b and 14f, the connecting conductor 16a is connected to the internal electrode 12A. The connecting conductor 16a is connected to the edge of the internal electrode 12A closer to the side surface 11d, for example, at a position closer to the end face 11e of the internal electrode 12A in the third direction D3. The connecting conductor 16a and the internal electrode 12A are connected, for example, physically and electrically. In the piezoelectric layers 14b and 14f, the connecting conductor 16b is connected to the internal electrode 12B. The connecting conductor 16b is connected to the edge of the internal electrode 12B closer to the side surface 11c, for example, at a position closer to the end face 11f of the internal electrode 12B in the third direction D3. The connecting conductor 16b and the internal electrode 12B are connected, for example, physically and electrically.

[0027] In the piezoelectric layers 14b and 14f, the connecting conductor 16c is connected to the internal electrode 12C. The connecting conductor 16c is connected to the edge of the internal electrode 12C closer to the side surface 11d, for example, at a position closer to the end face 11f of the internal electrode 12C in the third direction D3. The connecting conductor 16c and the internal electrode 12C are connected, for example, physically and electrically. In the piezoelectric layers 14b and 14f, the connecting conductor 16d is connected to the internal electrode 12D. The connecting conductor 16d is connected to the edge of the internal electrode 12D closer to the side surface 11c, for example, at a position closer to the end face 11e of the internal electrode 12D in the third direction D3. The connecting conductor 16d and the internal electrode 12D are connected, for example, physically and electrically.

[0028] The connecting conductors 16e1 and 16e2 are disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. The connecting conductors 16e1 and 16e2 are exposed, for example, at the same positions in the third direction D3 on corresponding ones of the pair of side surfaces 11c and 11d. In the piezoelectric layer 14c and the piezoelectric layer 14e, the connecting conductors 16e1 and 16e2 are connected to the internal electrode 12E. The connecting conductor 16e1 is connected, for example, to an edge of the internal electrode 12E closer to the side surface 11d, at approximately the center of the internal electrode 12D in the third direction D3. The connecting conductor 16e2 is connected, for example, to an edge of the internal electrode 12E closer to the side surface 11c, at approximately the center of the internal electrode 12D in the third direction D3. The connecting conductors 16e1 and 16e2 are connected, for example, physically and electrically, to the internal electrode 12E.

[0029] The connecting conductors 16f, 16g, 16h, and 16i are disposed on the piezoelectric layer 14d. In the piezoelectric layer 14d, the connecting conductors 16f and 16h are exposed on the side surface 11d at different positions in the third direction D3, for example. The connecting conductors 16g and 16i are exposed on the side surface 11c at different positions in the third direction D3, for example. The connecting conductors 16f and 16i are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example. The connecting conductors 16h and 16g are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example.

[0030] In the piezoelectric layer 14d, the connecting conductor 16f is connected to the internal electrode 12F. The connecting conductor 16f is connected to the edge of the internal electrode 12F closer to the side surface 11d, for example, at a position closer to the end face 11e of the internal electrode 12F in the third direction D3. The connecting conductor 16f and the internal electrode 12F are connected, for example, physically and electrically. In the piezoelectric layer 14d, the connecting conductor 16g is connected to the internal electrode 12G. The connecting conductor 16g is connected to the edge of the internal electrode 12G closer to the side surface 11c, for example, at a position closer to the end face 11f of the internal electrode 12G in the third direction D3. The connecting conductor 16g and the internal electrode 12G are connected, for example, physically and electrically.

[0031] In the piezoelectric layer 14d, the connecting conductor 16h is connected to the internal electrode 12H. The connecting conductor 16h is connected to the edge of the internal electrode 12H closer to the side surface 11d, for example, at a position closer to the end face 11f of the internal electrode 12H in the third direction D3. The connecting conductor 16h and the internal electrode 12H are connected, for example, physically and electrically. In the piezoelectric layer 14d, the connecting conductor 16i is connected to the internal electrode 12I. The connecting conductor 16i is connected to the edge of the internal electrode 12I closer to the side surface 11c, for example, at a position closer to the end face 11e of the internal electrode 12I in the third direction D3. The connecting conductor 16i and the internal electrode 12I are connected, for example, physically and electrically.

[0032] As shown in Figures 4 and 5, the internal electrodes 12A, 12B and the internal electrodes 12C, 12D arranged on the piezoelectric layer 14b face the internal electrode 12E arranged on the piezoelectric layer 14c via a part of the piezoelectric body 11. In this embodiment, the internal electrodes 12A and 12D arranged on the piezoelectric layer 14b face the internal electrode 12Ea arranged on the piezoelectric layer 14c via the piezoelectric layer 14. That is, in the relationship between the piezoelectric layer 14b and the piezoelectric layer 14c, the internal electrode 12Ea includes a portion facing the internal electrode 12A and a portion facing the internal electrode 12D. The internal electrodes 12B and 12C arranged on the piezoelectric layer 14b face the internal electrode 12Eb arranged on the piezoelectric layer 14c via the piezoelectric layer 14. That is, in the relationship between the piezoelectric layer 14b and the piezoelectric layer 14c, the internal electrode 12Eb includes a portion facing the internal electrode 12B and a portion facing the internal electrode 12C.

[0033] The internal electrode 12E disposed on the piezoelectric layer 14c faces the internal electrodes 12F, 12G and the internal electrodes 12H, 12I disposed on the piezoelectric layer 14d, with part of the piezoelectric body 11 interposed therebetween. In this embodiment, the internal electrode 12Ea disposed on the piezoelectric layer 14c faces the internal electrodes 12F and 12I disposed on the piezoelectric layer 14d, via the piezoelectric layer. That is, in the relationship between the piezoelectric layer 14c and the piezoelectric layer 14d, the internal electrode 12Ea includes a portion facing the internal electrode 12F and a portion facing the internal electrode 12I. The internal electrode 12Eb disposed on the piezoelectric layer 14c faces the internal electrodes 12G and 12H disposed on the piezoelectric layer 14d, via the piezoelectric layer 14. That is, in the relationship between the piezoelectric layer 14c and the piezoelectric layer 14d, the internal electrode 12Eb includes a portion facing the internal electrode 12G and a portion facing the internal electrode 12H.

[0034] The internal electrodes 12F, 12G and the internal electrodes 12H, 12I arranged on the piezoelectric layer 14d face the internal electrode 12E arranged on the piezoelectric layer 14e with part of the piezoelectric body 11 interposed therebetween. In this embodiment, the internal electrodes 12F and 12I arranged on the piezoelectric layer 14d face the internal electrode 12Ea arranged on the piezoelectric layer 14e via the piezoelectric layer 14. That is, in the relationship between the piezoelectric layer 14d and the piezoelectric layer 14e, the internal electrode 12Ea includes a portion facing the internal electrode 12F and a portion facing the internal electrode 12I. The internal electrodes 12G and 12H arranged on the piezoelectric layer 14d face the internal electrode 12Eb arranged on the piezoelectric layer 14e via the piezoelectric layer 14. That is, in the relationship between the piezoelectric layer 14d and the piezoelectric layer 14e, the internal electrode 12Eb includes a portion facing the internal electrode 12G and a portion facing the internal electrode 12H.

[0035] The internal electrode 12E disposed on the piezoelectric layer 14e faces the internal electrodes 12A, 12B and the internal electrodes 12C, 12D disposed on the piezoelectric layer 14f, with part of the piezoelectric body 11 interposed therebetween. In this embodiment, the internal electrode 12Ea disposed on the piezoelectric layer 14e faces the internal electrodes 12A and 12D disposed on the piezoelectric layer 14f, via the piezoelectric layer 14e. That is, in the relationship between the piezoelectric layer 14e and the piezoelectric layer 14f, the internal electrode 12Ea includes a portion facing the internal electrode 12A and a portion facing the internal electrode 12D. The internal electrode 12Eb disposed on the piezoelectric layer 14e faces the internal electrodes 12B and 12C disposed on the piezoelectric layer 14f, via the piezoelectric layer 14e. That is, in the relationship between the piezoelectric layer 14e and the piezoelectric layer 14f, the internal electrode 12Eb includes a portion facing the internal electrode 12B and a portion facing the internal electrode 12C.

[0036] Piezoelectric element 10 includes a portion P1 and a portion P2. Portions P1 and P2 comprise an active region in piezoelectric element 10 that is piezoelectrically active. In this specification, being piezoelectrically active includes generating a displacement upon application of a voltage and generating a charge upon the displacement. That is, in piezoelectric element 10, portions P1 and P2 are displaced upon application of a voltage or generate a charge upon the displacement. Portions P1 and P2, for example, generate a voltage upon displacement.

[0037] In this embodiment, the portion P1 includes the internal electrode 12C, a portion of the internal electrode 12Eb facing the internal electrode 12C, and a piezoelectric layer sandwiched between the internal electrode 12C and that portion of the internal electrode 12Eb. In the portion P1, the piezoelectric layer sandwiched between the internal electrode 12C and that portion of the internal electrode 12Eb constitutes an active region. Portion P1 includes the internal electrode 12D, a portion of the internal electrode 12Ea facing the internal electrode 12D, and a piezoelectric layer sandwiched between the internal electrode 12D and that portion of the internal electrode 12Ea. In portion P1, the piezoelectric layer sandwiched between the internal electrode 12D and that portion of the internal electrode 12Ea constitutes an active region.

[0038] Portion P1 includes the internal electrode 12H, a portion of the internal electrode 12Eb facing the internal electrode 12H, and a piezoelectric layer sandwiched between the internal electrode 12H and that portion of the internal electrode 12Eb. In portion P1, the piezoelectric layer sandwiched between the internal electrode 12H and that portion of the internal electrode 12Eb constitutes an active region. Portion P1 includes the internal electrode 12I, a portion of the internal electrode 12Ea facing the internal electrode 12I, and a piezoelectric layer sandwiched between the internal electrode 12I and that portion of the internal electrode 12Ea. In portion P1, the piezoelectric layer sandwiched between the internal electrode 12I and that portion of the internal electrode 12Ea forms an active region.

[0039] In this embodiment, the portion P2 includes the internal electrode 12A, a portion of the internal electrode 12Ea facing the internal electrode 12A, and a piezoelectric layer sandwiched between the internal electrode 12A and that portion of the internal electrode 12Ea. In the portion P2, the piezoelectric layer sandwiched between the internal electrode 12A and that portion of the internal electrode 12Ea forms an active region. Portion P2 includes the internal electrode 12B, a portion of the internal electrode 12Eb facing the internal electrode 12B, and a piezoelectric layer sandwiched between the internal electrode 12B and that portion of the internal electrode 12Eb. In portion P2, the piezoelectric layer sandwiched between the internal electrode 12B and that portion of the internal electrode 12Eb constitutes an active region.

[0040] Portion P2 includes the internal electrode 12F, a portion of the internal electrode 12Ea facing the internal electrode 12F, and a piezoelectric layer sandwiched between the internal electrode 12F and that portion of the internal electrode 12Ea. In portion P2, the piezoelectric layer sandwiched between the internal electrode 12F and that portion of the internal electrode 12Ea forms an active region. Portion P2 includes the internal electrode 12G, a portion of the internal electrode 12Eb facing the internal electrode 12G, and a piezoelectric layer sandwiched between the internal electrode 12G and that portion of the internal electrode 12Eb. In portion P2, the piezoelectric layer sandwiched between the internal electrode 12G and that portion of the internal electrode 12Eb constitutes an active region.

[0041] 2, the external electrodes 13 include external electrodes 13A, 13B, 13C, 13D, 13E, and 13F. The external electrodes 13A, 13B, 13C, 13D, 13E, and 13F have a rectangular shape when viewed from the second direction D2. In the present embodiment, the longitudinal direction of the external electrodes 13A, 13B, 13C, 13D, 13E, and 13F corresponds to the first direction D1, and the lateral direction of the external electrodes 13A, 13B, 13C, 13D, 13E, and 13F corresponds to the third direction D3. The longitudinal direction of the external electrodes 13A, 13B, 13C, 13D, 13E, and 13F may correspond to the third direction D3, and the lateral direction of the external electrodes 13A, 13B, 13C, 13D, 13E, and 13F may correspond to the first direction D1.

[0042] The external electrodes 13A, 13B, and 13C are arranged on the side surface 11c. The external electrodes 13A, 13B, and 13C are lined up in this order, for example, in the third direction D3, in the direction from the end surface 11e toward the end surface 11f. The external electrodes 13D, 13E, and 13F are arranged on the side surface 11d. The external electrodes 13D, 13E, and 13F are lined up in this order, for example, in the third direction D3, in the direction from the end surface 11e toward the end surface 11f.

[0043] In this embodiment, the external electrode 13A is connected to the connecting conductor 16d arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and the connecting conductor 16i arranged on the piezoelectric layer 14d, thereby electrically connecting the external electrode 13A to the internal electrode 12D arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and the internal electrode 12I arranged on the piezoelectric layer 14d. The external electrode 13B is connected to the connecting conductor 16e2 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 13B to the internal electrode 12E disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. The external electrode 13C is connected to the connecting conductor 16b arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and to the connecting conductor 16g arranged on the piezoelectric layer 14d, thereby electrically connecting the external electrode 13C to the internal electrode 12B arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and to the internal electrode 12G arranged on the piezoelectric layer 14d.

[0044] The external electrode 13D is connected to the connecting conductor 16a arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and to the connecting conductor 16f arranged on the piezoelectric layer 14d, thereby electrically connecting the external electrode 13D to the internal electrode 12A arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and to the internal electrode 12F arranged on the piezoelectric layer 14d. The external electrode 13E is connected to the connecting conductor 16e1 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 13E to the internal electrode 12E disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. The external electrode 13F is connected to the connecting conductor 16c arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and to the connecting conductor 16h arranged on the piezoelectric layer 14d, thereby electrically connecting the external electrode 13F to the internal electrode 12C arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and to the internal electrode 12H arranged on the piezoelectric layer 14d.

[0045] The external electrode 13 includes, for example, a sintered metal layer. The sintered metal layer is formed by drying and baking a conductive paste applied to the side surfaces 11c and 11d. The external electrode 13 is formed, for example, by sintering metal powder contained in the conductive paste. The sintered metal layer includes a conductive material such as a precious metal or a precious metal alloy. The precious metal includes, for example, Ag, Pd, Au, or Pt. The precious metal alloy includes, for example, an Ag-Pd alloy. The external electrode 13 may include a plating layer disposed on the sintered metal layer.

[0046] The amplifier 20 is electrically connected to the piezoelectric element 10 and amplifies the voltage generated in the piezoelectric body 11. The amplifier 20 is electrically connected to the external electrode 13C of the piezoelectric element 10, for example, by a wiring member (not shown). In this embodiment, the amplifier 20 amplifies the voltage generated in the portion P2 of the piezoelectric body 11. The operation unit OU outputs the voltage amplified by the amplifier 20 as a signal corresponding to the charge generated in the portion P2. In this embodiment, the operation unit OU outputs a voltage signal corresponding to the charge generated in the portion P2. The voltage signal is, for example, an analog signal. The voltage signal output from the operation unit OU is input to the control unit CU. The amplifier 20 is known in this technical field, and further detailed description will be omitted.

[0047] Here, the displacement of portion P2 changes depending on the force that piezoelectric element 10 receives from the operating body. For example, the greater the force that piezoelectric element 10 receives from the operating body, the more portion P2 is constrained by that force, making it more difficult for it to displace. That is, in piezoelectric element 10, the ease with which portion P2 can be displaced changes depending on the force that piezoelectric element 10 receives from the operating body. Therefore, the voltage signal output from operating unit OU also changes depending on the force that piezoelectric element 10 receives from the operating body. For example, the greater the force that piezoelectric element 10 receives from the operating body, the smaller the voltage signal.

[0048] The control unit CU is, for example, configured by a computer system. The computer system physically includes, for example, a processor (arithmetic circuit), a memory, a communication interface, and a storage unit. The memory includes, for example, a read-only memory (ROM) and a random access memory (RAM). The storage unit includes, for example, a hard disk drive (HDD) or a solid state drive (SSD). The control unit CU may be, for example, configured by a microcontroller or an integrated circuit.

[0049] The control unit CU applies a voltage to the piezoelectric element 10 and acquires information about the force that the piezoelectric element 10 receives from the operating body. The control unit CU acquires information about the force that the piezoelectric element 10 receives from the operating body, for example, by executing a program stored in a memory on a CPU. Through this processing, the control unit CU includes the functional elements shown in FIG. 3 . That is, the control unit CU includes an oscillator 30, a converter 40, and a processing unit 50.

[0050] The oscillator 30 is electrically connected to the piezoelectric element 10 and applies a voltage to the piezoelectric element 10. The oscillator 30 is electrically connected to the piezoelectric element 10, for example, by a wiring member (not shown). In this embodiment, the oscillator 30 is electrically connected to the external electrode 13A of the piezoelectric element 10. The oscillator 30 applies a voltage to the portion P1, for example, via the external electrode 13A. In this embodiment, the oscillator 30 applies a voltage to the internal electrode 12C and the internal electrode 12E, the internal electrode 12D and the internal electrode 12E, the internal electrode 12H and the internal electrode 12E, and the internal electrode 12I and the internal electrode 12E. That is, in this embodiment, the control unit CU applies a voltage to the portion P1.

[0051] As described above, in this embodiment, the oscillator 30 is electrically connected to the external electrode 13A, and the amplifier 20 is electrically connected to the external electrode 13C. In this case, for example, the external electrode 13B is also connected to the oscillator 30. That is, in this embodiment, the portion P1 is displaced by a voltage applied from the control unit CU. The displacement of the portion P1 is transmitted to the portion P2, which displaces the portion P2. The portion P2 generates a charge due to the displacement. In this embodiment, the portion P2 generates a voltage due to the displacement. Hereinafter, a case will be described as an example where the portion P1 is displaced due to the application of a voltage, and the portion P2 generates a charge due to the displacement.

[0052] The converter 40 converts the signal output from the operation unit OU into a digital signal. The converter 40 is, for example, electrically connected to the amplifier 20, and converts the voltage signal output from the amplifier 20 as an analog signal into a digital signal. The converter 40 includes, for example, a rectifier and an A / D converter. The converter 40 outputs the converted digital signal to the processing unit 50. The oscillator 30 and the converter 40 are known in the art, and further detailed description thereof will be omitted.

[0053] In this embodiment, the piezoelectric element 10, amplifier 20, oscillator 30, and converter 40 are connected as shown in Fig. 6. In the example shown in Fig. 6, the amplifier 20 includes a differential amplifier circuit 21. The oscillator 30 includes a capacitor 31, a resistor 32, an inverter 33, a resistor 34, and a capacitor 35. The oscillator 30 may include a NAND circuit instead of the inverter 33. The converter 40 includes a diode 41, a capacitor 42, and a resistor 43.

[0054] In the example shown in FIG. 6 , one end of the portion P1 is connected to the input end of the inverter 33, and the other end of the portion P1 is connected to the output end of the inverter 33 via a resistor 34. In this embodiment, the input end of the inverter 33 is connected to the external electrode 13B. The input end of the inverter 33 and the portion P1 are connected to each other via the external electrode 13B. Furthermore, the input end and output end of the inverter 33 are connected to each other via a resistor 32. One end of each of the portions P1 and P2 is grounded via a capacitor 31, and the other end of the portion P1 is grounded via a capacitor 35. The other end of the portion P2 is connected to the non-inverting input terminal of the differential amplifier circuit 21, and the voltage generated in the portion P2 is input to the non-inverting input terminal of the differential amplifier circuit 21. The inverting input terminal of the differential amplifier circuit 21 is grounded via the capacitor 31. The output terminal of the differential amplifier circuit 21 is connected to the input terminal of a diode 41.

[0055] The differential amplifier circuit 21 amplifies the input voltage generated in the portion P2 and outputs the amplified voltage to the diode 41. The differential amplifier circuit 21 outputs, for example, an AC voltage signal to the diode 41. The diode 41 converts the AC voltage signal output from the differential amplifier circuit 21 into a half-wave rectified signal. The output terminal of the diode 41 is connected to a capacitor 42 and a resistor 43. The capacitor 42 smoothes the half-wave rectified signal output from the output terminal of the diode 41. The resistor 43 is used to discharge the charge accumulated in the capacitor 42. Thus, in the example shown in FIG. 6 , a voltage signal corresponding to the charge generated in the portion P2 is amplified by the differential amplifier circuit 21, and the amplified voltage signal is converted into a half-wave rectified signal by the diode 41. The converted half-wave rectified signal is then smoothed by the capacitor 42, and the smoothed half-wave rectified signal is output to the A / D converter included in the converter 40.

[0056] The processing unit 50 acquires information about the force received from the operating object based on the signal output from the operation unit OU. First, the processing unit 50 acquires the digital signal output from the converter 40. That is, the processing unit 50 acquires voltage data in which a voltage signal corresponding to the charge generated in the part P2 has been converted into digital data. The voltage data includes, for example, a value based on the signal output from the operation unit OU. That is, the voltage data includes, for example, a value based on the signal corresponding to the charge generated in the part P2.

[0057] Next, the processing unit 50 compares a value based on the signal output from the operation unit OU, which is included in the acquired voltage data, with a reference value. In this embodiment, the processing unit 50 compares the value based on the signal output from the operation unit OU with the reference value, and calculates the difference between the value based on the signal output from the operation unit OU and the reference value. The reference value is, for example, a value based on the signal output from the operation unit OU when the piezoelectric element 10 is receiving a predetermined force from the operating body. In this embodiment, the predetermined force is zero. That is, in this embodiment, the reference value is a value based on the signal output from the operation unit OU in an initial state where no force is being received from the operating body. The predetermined force may be greater than zero.

[0058] The reference value may be stored in a storage unit included in the computer system constituting the control unit CU. Alternatively, the processing unit 50 may access a given database or file system to acquire the reference value each time the processing unit 50 receives a signal from the operation unit OU, or may acquire a reference value input to the control unit CU by a user.

[0059] Next, the processing unit 50 acquires information about the force applied from the operating object based on the result of the comparison. In this embodiment, the processing unit 50 acquires information about the force applied from the operating object based on the difference between a value based on the signal output from the operation unit OU and a reference value. For example, the processing unit 50 references information indicating the relationship between the difference and a value based on the magnitude of the force applied from the operating object, and acquires a value corresponding to the calculated difference. Then, the processing unit 50 acquires the acquired value based on the magnitude of the force applied from the operating object as information about the force applied from the operating object. That is, in this embodiment, the information about the force applied from the operating object includes information about the magnitude of the force. The processing unit 50 may output the acquired information about the force applied from the operating object to a display device (not shown).

[0060] The information about the force received from the operating object may include, for example, information about the presence or absence of the force. In this case, for example, when the difference between the value based on the signal output from the operating unit OU and the reference value is equal to or smaller than a predetermined threshold, the processing unit 50 acquires that the difference is equal to or smaller than the predetermined threshold as information indicating that no force is being received from the operating object. When the difference between the value based on the signal output from the operating unit OU and the reference value is greater than the predetermined threshold, the processing unit 50 may acquire that the difference is greater than the predetermined threshold as information indicating that a force is being received from the operating object.

[0061] As described above, in the input device ID, the operation unit OU includes a piezoelectric element 10 that receives force from an operating object, the piezoelectric element 10 including one piezoelectric body 11 including a portion P1 that is displaced by application of a voltage and a portion P2 that generates an electric charge due to the displacement. When the portion P1 in the piezoelectric body 11 is displaced, the displacement of the portion P1 is transmitted to the portion P2, causing the portion P2 to be displaced. When the piezoelectric element 10 receives a force from the operating object, a restraining force corresponding to the force acts on the piezoelectric body 11 including the portions P1 and P2. Therefore, the ease of displacement of the portion P2 changes depending on the force that the piezoelectric element 10 receives from the operating object. In other words, when the piezoelectric element 10 receives a force from the operating object, the displacement of the portion P2 changes depending on the force. As the displacement of the portion P2 changes, the electric charge generated in the portion P2 also changes. In this way, in the input device ID, the displacement of the portion P2 is displaced by the transmission of the displacement of the portion P1, and the displacement of the portion P2 changes in response to the force received from the operating object. However, if the displacement of the portion P1 is not properly transmitted to the portion P2, the displacement of the portion P2 may not change in response to the force received from the operating object. In other words, the ease with which the displacement is transmitted between the portions P1 and P2 affects the accuracy of the information related to the force received from the operating object. In the input device ID, the portions P1 and P2 are included in the piezoelectric body 11, and therefore the displacement of the portion P1 is more easily transmitted to the portion P2 than when the portions P1 and P2 are included in separate piezoelectric bodies. As a result of the above, the input device ID improves the accuracy of information relating to the force received from the operating object.

[0062] Here, an example of voltage data acquired by the processing unit 50 will be described with reference to Fig. 7 and Fig. 8. Fig. 7 is a diagram showing an example of control processing in the input device, and is a diagram showing an example of voltage data regarding the voltage applied to part P1. Fig. 8 is a diagram showing an example of control processing in the input device, and is a diagram showing an example of voltage data acquired by the processing unit 50. The horizontal axis of the graphs shown in Fig. 7 and Fig. 8 represents time, and the vertical axis represents voltage data.

[0063] 7, change G1 is a graph showing voltage data regarding the voltage applied to portion P1 in an initial state in which the piezoelectric element 10 is not receiving force from the operating body, and change G2 is a graph showing voltage data regarding the voltage applied to portion P1 in a state in which the piezoelectric element 10 is receiving a constant force from the operating body. Comparing change G1 and change G2, it can be seen that although there are differences between the voltage data for change G1 and the voltage data for change G2 at multiple points in time, there is not a significant difference between the outlines of change G1 and change G2. In other words, it can be seen from FIG. 7 that even if the piezoelectric element 10 receives force from the operating body, the voltage data regarding the voltage applied to portion P1 is unlikely to change.

[0064] In FIG. 8, change G3 is a graph showing voltage data acquired by the processing unit 50 in an initial state in which the piezoelectric element 10 is not receiving force from the operating body, and change G4 is a graph showing voltage data acquired by the processing unit 50 in a state in which the piezoelectric element 10 is receiving a constant force from the operating body. Comparing change G3 and change G4, it can be seen that the contours of change G3 and change G4 are different from each other, and the voltage data at change G4 changes less than the voltage data at change G3. That is, FIG. 8 shows that when the piezoelectric element 10 receives force from the operating body, the change in the voltage data acquired by the processing unit 50 decreases. The reason for this difference between change G1 and change G2 is that, as described above, when the piezoelectric element 10 receives force from the operating body, a restraining force acts on the piezoelectric body 11, changing the ease of displacement of portion P2.

[0065] In the input device ID, the control unit CU compares a value based on a signal output from the operation unit OU with a reference value, and obtains information about the force received from the operating object based on the result of the comparison. The control unit CU compares a value based on a signal output from the operation unit OU with a reference value, thereby enabling the control unit CU to accurately grasp a change in the force applied from the operating object to the piezoelectric element 10. Therefore, the input device ID further improves the accuracy of information related to the force applied from the operating object.

[0066] In the input device ID, the reference value is a value based on a signal output from the operation unit OU in an initial state in which the piezoelectric element 10 is not receiving force from the operation object. By using the initial state as a reference, the control unit CU can more accurately grasp the change in the force that the piezoelectric element 10 receives from the operating object. Therefore, the input device ID more reliably improves the accuracy of the information related to the force that the input device ID receives from the operating object.

[0067] In the input device ID, the control unit CU acquires information about the force that the piezoelectric element 10 receives from the operating object, based on the difference between the value based on the signal output from the operation unit OU and the reference value. The difference between the value based on the signal output from the operation unit OU and the reference value indicates the amount of change from the reference value. By using the amount of change from the reference value as the basis, the control unit CU can more reliably and accurately grasp the change in the force that the piezoelectric element 10 receives from the operating object. Therefore, the input device ID can more reliably improve the accuracy of the information regarding the force that is received from the operating object.

[0068] The force that the piezoelectric element 10 receives from the operating body includes a force whose magnitude does not change over time. Hereinafter, a force whose magnitude does not change over time may be referred to as a "static load." Ideally, piezoelectric ceramic materials are perfect insulators. However, in reality, piezoelectric ceramic materials have finite insulation resistance. Therefore, when the piezoelectric element 10 receives a static load from the operating body, the charge generated by the portion P2 will discharge over time. Meanwhile, as described above, there is a difference in the voltage data, which is the signal output from the operation unit OU, between the initial state in which the piezoelectric element 10 receives no force from the operating body and the state in which the piezoelectric element 10 receives a constant force from the operating body. In other words, by using the voltage data as the signal output from the operation unit OU, the static load that the piezoelectric element 10 receives from the operating body can be detected. Therefore, the input device ID can acquire information about the force even when the force that the piezoelectric element 10 receives from the operating body is a static load.

[0069] Next, the configuration of a first modified example of the input device ID according to this embodiment will be described with reference to FIGS. 9 and 10. FIG. 9 is an exploded perspective view of a piezoelectric element. FIG. 10 is a diagram showing the cross-sectional configuration of the piezoelectric element. Hatching has been omitted in FIG. 10 to clearly show each part. This modified example differs from the above-described embodiment in terms of the configuration of the internal electrode 12. Below, the differences between the above-described embodiment and this modified example will be mainly described.

[0070] 9, in this modification, the internal electrode 12 includes a plurality of internal electrodes 121A, a plurality of internal electrodes 121C, and an internal electrode 12E. Each of the internal electrodes 121A and 121C has a rectangular shape. That is, in this modification, the piezoelectric element 10 includes a plurality of internal electrodes 121A, 121C, and 12E.

[0071] The internal electrode 121A and the internal electrode 121C are arranged on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f. The internal electrode 121A is arranged closer to the end face 11e than the center of the piezoelectric layers 14b, 14d, and 14f in the third direction D3 when viewed from the first direction D1. The internal electrode 121C is arranged closer to the end face 11f than the center of the piezoelectric layers 14b, 14d, and 14f in the third direction D3 when viewed from the first direction D1. The internal electrodes 121A and 121C are spaced apart from each other on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f.

[0072] In this modification, the piezoelectric body 11 includes connecting conductors 161a1, 161a2, 161c1, 161c2, 16e1, and 16e2. The connecting conductors 161a1, 161c1, and 16e1 are exposed on the side surface 11d. The connecting conductors 161a2, 161c2, and 16e2 are exposed on the side surface 11c.

[0073] The connecting conductors 161a1, 161a2, 161c1, and 161c2 are disposed on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f. On the piezoelectric layers 14b, 14d, and 14f, the connecting conductors 161a1 and 161c1 are exposed on the side surface 11d at different positions in the third direction D3, for example. The connecting conductors 161a2 and 161c2 are exposed on the side surface 11c at different positions in the third direction D3, for example. The connecting conductors 161a1 and 161a2 are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example. The connecting conductors 161c1 and 161c2 are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example.

[0074] In the piezoelectric layers 14b, 14d, and 14f, the connecting conductors 161a1 and 161a2 are connected to the internal electrode 121A. The connecting conductor 161a1 is connected to the edge of the internal electrode 121A closer to the side surface 11d, for example, at a position closer to the end face 11e of the internal electrode 121A in the third direction D3. The connecting conductor 161a2 is connected to the edge of the internal electrode 121A closer to the side surface 11c, for example, at a position closer to the end face 11e of the internal electrode 121A in the third direction D3. The connecting conductors 161a1 and 161a2 and the internal electrode 121A are connected, for example, physically and electrically.

[0075] In the piezoelectric layers 14b, 14d, and 14f, the connecting conductors 161c1 and 161c2 are connected to the internal electrode 121C. The connecting conductor 161c1 is connected to the edge of the internal electrode 121C closer to the side surface 11d, for example, at a position closer to the end face 11f of the internal electrode 121C in the third direction D3. The connecting conductor 161c2 is connected to the edge of the internal electrode 121C closer to the side surface 11c, for example, at a position closer to the end face 11f of the internal electrode 121C in the third direction D3. The connecting conductors 161c1 and 161c2 are connected to the internal electrode 121C, for example, physically and electrically.

[0076] 10, the internal electrodes 121A and 121C arranged on the piezoelectric layer 14b face the internal electrode 12E arranged on the piezoelectric layer 14c across a portion of the piezoelectric body 11. In this modification, the internal electrode 121A arranged on the piezoelectric layer 14b faces the internal electrode 12Ea arranged on the piezoelectric layer 14c across the piezoelectric layer. The internal electrode 121C arranged on the piezoelectric layer 14b faces the internal electrode 12Eb arranged on the piezoelectric layer 14c across the piezoelectric layer.

[0077] The internal electrode 12E arranged on the piezoelectric layer 14c faces the internal electrodes 121A and 121C arranged on the piezoelectric layer 14d through a part of the piezoelectric body 11. In this modification, the internal electrode 12Ea arranged on the piezoelectric layer 14c faces the internal electrode 121A arranged on the piezoelectric layer 14d through the piezoelectric layer. The internal electrode 12Eb arranged on the piezoelectric layer 14c faces the internal electrode 121C arranged on the piezoelectric layer 14d through the piezoelectric layer.

[0078] The internal electrodes 121A and 121C arranged on the piezoelectric layer 14d face the internal electrode 12E arranged on the piezoelectric layer 14e across a part of the piezoelectric body 11. In this modification, the internal electrode 121A arranged on the piezoelectric layer 14d faces the internal electrode 12Ea arranged on the piezoelectric layer 14e across the piezoelectric layer. The internal electrode 121C arranged on the piezoelectric layer 14d faces the internal electrode 12Eb arranged on the piezoelectric layer 14e across the piezoelectric layer.

[0079] The internal electrode 12E arranged on the piezoelectric layer 14e faces the internal electrodes 121A and 121C arranged on the piezoelectric layer 14f, via a part of the piezoelectric body 11. In this modification, the internal electrode 12Ea arranged on the piezoelectric layer 14e faces the internal electrode 121A arranged on the piezoelectric layer 14f, via the piezoelectric layer. The internal electrode 12Eb arranged on the piezoelectric layer 14e faces the internal electrode 121C arranged on the piezoelectric layer 14f, via the piezoelectric layer.

[0080] In this modification, the portion P1 includes the internal electrode 121C, the internal electrode 12Eb, and a piezoelectric layer sandwiched between the internal electrodes 121C and 12Eb. In the portion P1, the piezoelectric layer sandwiched between the internal electrodes 121C and 12Eb constitutes an active region. In this modification, the portion P2 includes the internal electrode 121A, the internal electrode 12Ea, and a piezoelectric layer sandwiched between the internal electrodes 121A and 12Ea. In the portion P2, the piezoelectric layer sandwiched between the internal electrodes 121A and 12Ea constitutes an active region.

[0081] In this modification, the external electrode 13A is connected to the connecting conductors 161a2 disposed on the piezoelectric layers 14b, 14d, and 14f, thereby electrically connecting the external electrode 13A to the internal electrodes 121A disposed on the piezoelectric layers 14b, 14d, and 14f. The external electrode 13B is connected to the connecting conductor 16e2 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 13B to the internal electrode 12E disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. The external electrode 13C is connected to the connecting conductor 161c2 disposed on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f, thereby electrically connecting the external electrode 13C to the internal electrode 121C disposed on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f.

[0082] The external electrode 13D is connected to the connecting conductors 161a1 arranged on the piezoelectric layers 14b, 14d, and 14f, and is thereby electrically connected to the internal electrodes 121A arranged on the piezoelectric layers 14b, 14d, and 14f. The external electrode 13E is connected to the connecting conductor 16e1 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 13E to the internal electrode 12E disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. The external electrode 13F is connected to the connecting conductor 161c1 disposed on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f, thereby electrically connecting the external electrode 13F to the internal electrode 121C disposed on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f.

[0083] In this modification, the amplifier 20 is electrically connected to the external electrode 13A. The oscillator 30 is electrically connected to the external electrode 13C. In this modification, the oscillator 30 is also electrically connected to the external electrode 13B. This causes the oscillator 30 to apply a voltage to the portion P1. In this modification, the oscillator 30 applies a voltage to the internal electrode 121C and the internal electrode 12E.

[0084] Next, the configuration of a second modified example of the input device ID according to this embodiment will be described with reference to Figs. 11, 12, and 13. Fig. 11 is a perspective view of a piezoelectric element. Fig. 12 is an exploded perspective view of the piezoelectric element. Fig. 13 is a diagram showing the cross-sectional configuration of the piezoelectric element. Hatching has been omitted in Fig. 13 to clearly show each part. This modified example differs from the above-described embodiment in terms of the configurations of the internal electrode 12 and the external electrode 13. Below, the differences between the above-described embodiment and this modified example will be mainly described.

[0085] 12, in this modification, the internal electrode 12 includes a plurality of internal electrodes 122A, a plurality of internal electrodes 122C, and an internal electrode 122E. Each of the internal electrodes 122A, 122C, and 122E has a rectangular shape. That is, in this modification, the piezoelectric element 10 includes a plurality of internal electrodes 122A, 122C, and 122E.

[0086] The internal electrode 122A and the internal electrode 122C are arranged on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f. When viewed from the first direction D1, the internal electrode 122A is arranged closer to the side surface 11d than the center in the second direction D2 of each of the piezoelectric layers 14b, 14d, and 14f. When viewed from the first direction D1, the internal electrode 122C is arranged closer to the side surface 11c than the center in the second direction D2 of each of the piezoelectric layers 14b, 14d, and 14f. On the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f, the internal electrode 122A and the internal electrode 122C are spaced apart from each other.

[0087] The internal electrode 122E is disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. The internal electrode 122E has, for example, a rectangular shape. In this embodiment, the internal electrode 122E has a rectangular shape that is slightly smaller than the rectangular shape of the piezoelectric body 11 when viewed from the first direction D1. In this modification, the internal electrode 122E includes an internal electrode 122Ea and an internal electrode 122Eb. When viewed from the first direction D1, the internal electrode 122Ea is disposed closer to the side surface 11d than the center of each of the piezoelectric layers 14c and 14e in the second direction D2. When viewed from the first direction D1, the internal electrode 122Eb is disposed closer to the side surface 11c than the center of each of the piezoelectric layers 14c and 14e in the second direction D2. In this modification, the internal electrodes 122Ea and 122Eb are integral with each other.

[0088] In this modification, the piezoelectric body 11 includes connecting conductors 162a, 162c, 162e1, and 162e2. The connecting conductors 162a and 162e1 are exposed at the side surface 11d. The connecting conductors 162c and 162e2 are exposed at the side surface 11c.

[0089] The connecting conductors 162a and 162c are disposed on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14. In the piezoelectric layers 14b, 14d, and 14f, the connecting conductors 162a and 162c are exposed on corresponding ones of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example. The connecting conductors 162e1 and 162e2 are disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. On the piezoelectric layers 14c and 14e, the connecting conductors 162e1 and 162e2 are exposed on corresponding ones of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example.

[0090] In the piezoelectric layers 14b, 14d, and 14f and the piezoelectric layers 14c and 14e, the connecting conductor 162a and the connecting conductor 162e1 are exposed on the side surface 11d at different positions in the third direction D3. In the piezoelectric layers 14b, 14d, and 14f and the piezoelectric layers 14c and 14e, the connecting conductor 162c and the connecting conductor 162e2 are exposed on the side surface 11c at different positions in the third direction D3.

[0091] In the piezoelectric layers 14b, 14d, and 14f, the connecting conductor 162a is connected to the internal electrode 122A. The connecting conductor 162a is connected to the edge of the internal electrode 122A closer to the side surface 11d, for example, at a position closer to the end face 11e of the internal electrode 122A in the third direction D3. The connecting conductor 162a and the internal electrode 122A are connected, for example, physically and electrically. In the piezoelectric layers 14b, 14d, and 14f, the connecting conductor 162c is connected to the internal electrode 122C. The connecting conductor 162c is connected to the edge of the internal electrode 122C closer to the side surface 11c, for example, at a position closer to the end face 11e of the internal electrode 122C in the third direction D3. The connecting conductor 162c and the internal electrode 122C are connected, for example, physically and electrically.

[0092] In the piezoelectric layers 14c and 14e, the connecting conductor 162e1 is connected to the internal electrode 122E. The connecting conductor 162e1 is connected to the edge of the internal electrode 122Ea closer to the side surface 11d, for example, at a position closer to the end face 11f of the internal electrode 122E in the third direction D3. The connecting conductor 162e1 and the internal electrode 122Ea are connected, for example, physically and electrically. In the piezoelectric layers 14c and 14e, the connecting conductor 162e2 is connected to the internal electrode 122E. The connecting conductor 162e2 is connected to the edge of the internal electrode 122Eb closer to the side surface 11c, for example, at a position closer to the end face 11f of the internal electrode 122E in the third direction D3. The connecting conductor 162e2 and the internal electrode 122Eb are connected, for example, physically and electrically.

[0093] 13, the internal electrodes 122A and 122C arranged on the piezoelectric layer 14b face the internal electrode 122E arranged on the piezoelectric layer 14c across a portion of the piezoelectric body 11. In this modification, the internal electrode 122A arranged on the piezoelectric layer 14b faces the internal electrode 122Ea arranged on the piezoelectric layer 14c across the piezoelectric layer. The internal electrode 122C arranged on the piezoelectric layer 14b faces the internal electrode 122Eb arranged on the piezoelectric layer 14c across the piezoelectric layer.

[0094] The internal electrode 122E arranged on the piezoelectric layer 14c faces the internal electrodes 122A and 122C arranged on the piezoelectric layer 14d across a part of the piezoelectric body 11. In this modification, the internal electrode 122Ea arranged on the piezoelectric layer 14c faces the internal electrode 122A arranged on the piezoelectric layer 14d across the piezoelectric layer. The internal electrode 122Eb arranged on the piezoelectric layer 14c faces the internal electrode 122C arranged on the piezoelectric layer 14d across the piezoelectric layer.

[0095] The internal electrodes 122A and 122C arranged on the piezoelectric layer 14d face the internal electrode 122E arranged on the piezoelectric layer 14e across a part of the piezoelectric body 11. In this modification, the internal electrode 122A arranged on the piezoelectric layer 14d faces the internal electrode 122Ea arranged on the piezoelectric layer 14e across the piezoelectric layer. The internal electrode 122C arranged on the piezoelectric layer 14d faces the internal electrode 122Eb arranged on the piezoelectric layer 14e across the piezoelectric layer.

[0096] The internal electrode 122E arranged on the piezoelectric layer 14e faces the internal electrodes 122A and 122C arranged on the piezoelectric layer 14f, via a part of the piezoelectric body 11. In this modification, the internal electrode 122Ea arranged on the piezoelectric layer 14e faces the internal electrode 122A arranged on the piezoelectric layer 14f, via the piezoelectric layer. The internal electrode 122Eb arranged on the piezoelectric layer 14e faces the internal electrode 122C arranged on the piezoelectric layer 14f, via the piezoelectric layer.

[0097] In this modification, the portion P1 includes the internal electrode 122C, the internal electrode 122Eb, and a piezoelectric layer sandwiched between the internal electrodes 122C and 122Eb. In the portion P1, the piezoelectric layer sandwiched between the internal electrodes 122C and 122Eb forms an active region. In this modification, the portion P2 includes the internal electrode 122A, the internal electrode 122Ea, and a piezoelectric layer sandwiched between the internal electrodes 122A and 122Ea. In the portion P1, the piezoelectric layer sandwiched between the internal electrodes 122A and 122Ea forms an active region.

[0098] In this modification, as shown in Fig. 11, the external electrode 13 includes external electrodes 132A, 132B, 132D, and 132E. The external electrodes 132A, 132B, 132D, and 132E have a rectangular shape when viewed from the second direction D2. In this modification, the longitudinal direction of the external electrodes 132A, 132B, 132D, and 132E corresponds to the first direction D1, and the lateral direction of the external electrodes 132A, 132B, 132D, and 132E corresponds to the third direction D3. The longitudinal direction of the external electrodes 132A, 132B, 132D, and 132E may correspond to the third direction D3. The lateral direction of the external electrodes 132A, 132B, 132D, and 132E may correspond to the first direction D1.

[0099] The external electrodes 132A and 132B are arranged on the side surface 11c. The external electrodes 132A and 132B are lined up in this order, for example, in the third direction D3, in the direction from end surface 11e to end surface 11f. The external electrodes 132D and 132E are arranged on the side surface 11d. The external electrodes 132D and 132E are lined up in this order, for example, in the third direction D3, in the direction from end surface 11e to end surface 11f.

[0100] In this modification, the external electrode 132A is connected to the connecting conductor 162c disposed on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f, thereby electrically connecting the external electrode 132A to the internal electrodes 122C disposed on the piezoelectric layer 14b, the piezoelectric layer 14d, and the piezoelectric layer 14f. The external electrode 132B is connected to the connecting conductor 162e2 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 132B to the internal electrode 122E disposed on the piezoelectric layer 14c and the piezoelectric layer 14e.

[0101] The external electrode 132D is connected to the connecting conductor 162a disposed on the piezoelectric layer 14b and the piezoelectric layer 14f, thereby electrically connecting the external electrode 132D to the internal electrode 122A disposed on the piezoelectric layer 14b and the piezoelectric layer 14f. The external electrode 132E is connected to the connecting conductor 162e1 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 132E to the internal electrode 122E disposed on the piezoelectric layer 14c and the piezoelectric layer 14e.

[0102] In this modification, the amplifier 20 is electrically connected to the external electrode 132D. The oscillator 30 is electrically connected to the external electrode 132A. In this modification, the oscillator 30 is also electrically connected to the external electrode 132B. This causes the oscillator 30 to apply a voltage to the portion P1. In this modification, the oscillator 30 applies a voltage to the internal electrodes 122C and 122E.

[0103] Next, the configuration of a third modified example of the input device ID according to this embodiment will be described with reference to FIGS. 14, 15, and 16. FIG. 14 is a perspective view of a piezoelectric element. FIG. 15 is an exploded perspective view of the piezoelectric element. FIG. 16 is a diagram showing the cross-sectional configuration of the piezoelectric element. Hatching has been omitted in FIG. 16 to clearly show each part. This modified example differs from the above-described embodiment in terms of the configurations of the piezoelectric body 11, internal electrode 12, and external electrode 13. Below, the differences between the above-described embodiment and this modified example will be mainly described.

[0104] As shown in FIG. 15, in this modification, the piezoelectric body 11 includes piezoelectric layers 14g and 14h in addition to the piezoelectric layers 14a to 14f. In this modification, the piezoelectric layers 14a to 14h are arranged in this order in the first direction D1. The piezoelectric body 11 also includes one or more piezoelectric layers positioned between the plurality of piezoelectric layers 14a to 14h. Like the piezoelectric layers 14a to 14f, the piezoelectric layers 14g and 14h have a rectangular shape when viewed in the first direction D1. The piezoelectric layers 14g and 14h include a piezoelectric ceramic material.

[0105] 15, in this modification, the internal electrode 12 includes a plurality of internal electrodes 123A, a plurality of internal electrodes 123C, and a plurality of internal electrodes 123E. Each of the internal electrodes 123A, 123C, and 123E has a rectangular shape. That is, in this modification, the piezoelectric element 10 includes a plurality of internal electrodes 123A, 123C, and 123E.

[0106] The internal electrode 123A is disposed on the piezoelectric layer 14b and the piezoelectric layer 14d. The internal electrode 123A has, for example, a rectangular shape. In this embodiment, the internal electrode 123A has a rectangular shape that is slightly smaller than the rectangular shape of the piezoelectric body 11 when viewed from the first direction D1. The internal electrode 123C is disposed on the piezoelectric layer 14f and the piezoelectric layer 14h. The internal electrode 123C has, for example, a rectangular shape. In this embodiment, the internal electrode 123C has a rectangular shape that is slightly smaller than the rectangular shape of the piezoelectric body 11 when viewed from the first direction D1. The internal electrodes 123E are disposed on the piezoelectric layers 14c, 14e, and 14g. The internal electrodes 123E have, for example, a rectangular shape. In this embodiment, the internal electrodes 123E have a rectangular shape that is slightly smaller than the rectangular shape of the piezoelectric body 11 when viewed from the first direction D1.

[0107] In this modification, the piezoelectric body 11 includes connecting conductors 163a1, 163a2, 163c1, 163c2, 163e1, and 163e2. The connecting conductors 163a1, 163c1, and 163e1 are exposed on the side surface 11d. The connecting conductors 163a2, 163c2, and 163e2 are exposed on the side surface 11c.

[0108] The connecting conductors 163a1 and 163a2 are disposed on the piezoelectric layer 14b and the piezoelectric layer 14d. The connecting conductors 163a1 and 163a2 are exposed on corresponding ones of the pair of side surfaces 11c and 11d at different positions in the third direction D3, for example. The connecting conductors 163c1 and 163c2 are disposed on the piezoelectric layer 14f and the piezoelectric layer 14h. The connecting conductors 163c1 and 163c2 are exposed on corresponding ones of the pair of side faces 11c and 11d at different positions in the third direction D3, for example. The connecting conductors 163e1 and 163e2 are disposed on the piezoelectric layer 14c, the piezoelectric layer 14e, and the piezoelectric layer 14g. The connecting conductors 163e1 and 163e2 are exposed on corresponding ones of the pair of side faces 11c and 11d at the same positions in the third direction D3, for example.

[0109] In the piezoelectric layers 14b and 14d, the connecting conductors 163a1 and 163a2 are connected to the internal electrode 123A. The connecting conductor 163a1 is connected to the edge of the internal electrode 123A closer to the side surface 11d, for example, at a position closer to the end face 11f of the internal electrode 123A in the third direction D3. The connecting conductor 163a2 is connected to the edge of the internal electrode 123A closer to the side surface 11c, for example, at a position closer to the end face 11e of the internal electrode 123A in the third direction D3. The connecting conductors 163a1 and 163a2 are connected to the internal electrode 123A, for example, physically and electrically.

[0110] In the piezoelectric layers 14f and 14h, the connecting conductors 163c1 and 163c2 are connected to the internal electrode 123C. The connecting conductor 163c1 is connected to the edge of the internal electrode 123C closer to the side surface 11d, for example, at a position closer to the end face 11e of the internal electrode 123C in the third direction D3. The connecting conductor 163c2 is connected to the edge of the internal electrode 123C closer to the side surface 11c, for example, at a position closer to the end face 11f of the internal electrode 123C in the third direction D3. The connecting conductors 163c1 and 163c2 are connected to the internal electrode 123C, for example, physically and electrically.

[0111] In the piezoelectric layers 14c, 14e, and 14g, the connecting conductors 163e1 and 163e2 are connected to the internal electrode 123E. The connecting conductor 163e1 is connected to the edge of the internal electrode 123E closer to the side surface 11d, for example, at approximately the center of the internal electrode 123E in the third direction D3. The connecting conductor 163e2 is connected to the edge of the internal electrode 123E closer to the side surface 11c, for example, at approximately the center of the internal electrode 123E in the third direction D3. The connecting conductors 163e1 and 163e2 and the internal electrode 123E are connected, for example, physically and electrically.

[0112] 16, the internal electrode 123A arranged on the piezoelectric layer 14b faces the internal electrode 123E arranged on the piezoelectric layer 14c across the piezoelectric layer. The internal electrode 123E arranged on the piezoelectric layer 14c faces the internal electrode 123A arranged on the piezoelectric layer 14d across the piezoelectric layer. The internal electrode 123A arranged on the piezoelectric layer 14d faces the internal electrode 123E arranged on the piezoelectric layer 14e across the piezoelectric layer.

[0113] The internal electrode 123E arranged on the piezoelectric layer 14e faces the internal electrode 123C arranged on the piezoelectric layer 14f, via a piezoelectric layer. The internal electrode 123C arranged on the piezoelectric layer 14f faces the internal electrode 123E arranged on the piezoelectric layer 14g, via a piezoelectric layer. The internal electrode 123E arranged on the piezoelectric layer 14g faces the internal electrode 123C arranged on the piezoelectric layer 14h, via a piezoelectric layer.

[0114] In this modification, portion P1 includes an internal electrode 123A, an internal electrode 123E, and a piezoelectric layer sandwiched between the internal electrodes 123A and 123E. In portion P1, the piezoelectric layer sandwiched between the internal electrodes 123A and 123E constitutes an active region. In this modification, portion P2 includes an internal electrode 123C, an internal electrode 123E, and a piezoelectric layer sandwiched between the internal electrodes 123C and 123E. In portion P2, the piezoelectric layer sandwiched between the internal electrodes 123C and 123E constitutes an active region.

[0115] 14, the external electrode 13 includes external electrodes 133A, 133B, 133C, 133D, 133E, and 133F. The external electrodes 133A, 133B, 133C, 133D, 133E, and 133F have a rectangular shape when viewed from the second direction D2. In this modification, the longitudinal direction of the external electrodes 133A, 133B, 133C, 133D, 133E, and 133F corresponds to the first direction D1, and the lateral direction of the external electrodes 133A, 133B, 133C, 133D, 133E, and 133F corresponds to the third direction D3. The longitudinal direction of the external electrodes 133A, 133B, 133C, 133D, 133E, and 133F may correspond to the third direction D3. The short-side direction of the external electrodes 133A, 133B, 133C, 133D, 133E, and 133F may correspond to the first direction D1.

[0116] The external electrodes 133A, 133B, and 133C are arranged on the side surface 11c. The external electrodes 133A, 133B, and 133C are lined up in this order, for example, in the third direction D3, in the direction from end surface 11e toward end surface 11f. The external electrodes 133D, 133E, and 133F are arranged on the side surface 11d. The external electrodes 133D, 133E, and 133F are lined up in this order, for example, in the third direction D3, in the direction from end surface 11e toward end surface 11f.

[0117] In this modification, the external electrode 133A is connected to the connecting conductors 163a2 disposed on the piezoelectric layers 14b and 14d, thereby electrically connecting the external electrode 133A to the internal electrodes 123A disposed on the piezoelectric layers 14b and 14d. The external electrode 133B is connected to the connecting conductor 163e2 disposed on the piezoelectric layer 14c, the piezoelectric layer 14e, and the piezoelectric layer 14g, thereby electrically connecting the external electrode 133B to the internal electrode 123E disposed on the piezoelectric layer 14c, the piezoelectric layer 14e, and the piezoelectric layer 14g. The external electrode 133C is connected to the connecting conductor 163c2 disposed on the piezoelectric layer 14f and the piezoelectric layer 14h, thereby electrically connecting the external electrode 133C to the internal electrode 123C disposed on the piezoelectric layer 14f and the piezoelectric layer 14h.

[0118] The external electrode 133D is connected to the connecting conductor 163c1 disposed on the piezoelectric layer 14f and the piezoelectric layer 14h, thereby electrically connecting the external electrode 133D to the internal electrode 123C disposed on the piezoelectric layer 14f and the piezoelectric layer 14h. The external electrode 133E is connected to the connecting conductor 163e1 disposed on the piezoelectric layer 14c, the piezoelectric layer 14e, and the piezoelectric layer 14g, thereby electrically connecting the external electrode 133E to the internal electrode 123E disposed on the piezoelectric layer 14c, the piezoelectric layer 14e, and the piezoelectric layer 14g. The external electrode 133F is connected to the connecting conductor 163a1 disposed on the piezoelectric layer 14b and the piezoelectric layer 14d, thereby electrically connecting the external electrode 133F to the internal electrode 123A disposed on the piezoelectric layer 14b and the piezoelectric layer 14d.

[0119] In this modification, the amplifier 20 is electrically connected to the external electrode 133C. The oscillator 30 is electrically connected to the external electrode 133A. In this modification, the oscillator 30 is also electrically connected to the external electrode 133B. This causes the oscillator 30 to apply a voltage to the portion P1. In this modification, the oscillator 30 applies a voltage to the internal electrode 123A and the internal electrode 123E.

[0120] Next, the configuration of a fourth modified example of the input device ID according to this embodiment will be described with reference to FIGS. 17, 18, 19, and 20. FIG. 17 is a perspective view of a piezoelectric element. FIG. 18 is an exploded perspective view of the piezoelectric element. FIG. 19 is a diagram showing the cross-sectional configuration of the piezoelectric element. FIG. 20 is a diagram showing the cross-sectional configuration of the piezoelectric element. Hatching has been omitted in FIGS. 19 and 20 to clearly show each part. This modified example differs from the above-described embodiment in terms of the configurations of the internal electrode 12 and the external electrode 13. Below, the differences between the above-described embodiment and this modified example will be mainly described.

[0121] As shown in FIG. 18, in this modified example, the internal electrode 12 includes a pair of internal electrodes 12A, 12B, a pair of internal electrodes 12C, 12D, a plurality of internal electrodes 124E, a pair of internal electrodes 12F, 12G, and a pair of internal electrodes 12H, 12I. In this modification, in the piezoelectric layer 14b and the piezoelectric layer 14f, the internal electrode 12C and the internal electrode 12D are physically and electrically connected by the connecting portion 154a.

[0122] The internal electrode 124E is disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. In this modification, the internal electrode 124E includes a pair of internal electrodes 124Ea and 124Eb and a pair of internal electrodes 124Ec and 124Ed. The internal electrodes 124Ea and 124Eb are arranged at the diagonal corner of the rectangular shape of the piezoelectric body 11. In this modification, the internal electrode 124Ea is arranged at the corner formed by the side surface 11d and the end surface 11e, and the internal electrode 124Eb is arranged at the corner formed by the side surface 11c and the end surface 11f. The internal electrodes 124Ec and 124Ed are arranged at the other diagonal corners of the rectangular shape of the piezoelectric body 11. In this modification, the internal electrode 124Ec is arranged at the corner formed by the side surface 11c and the end surface 11e, and the internal electrode 124Ed is arranged at the corner formed by the side surface 11c and the end surface 11e.

[0123] In the piezoelectric layers 14c and 14e, the internal electrodes 124Ea and 124Ec are adjacent to the side surface 11d, and the internal electrodes 124Eb and 124Ed are adjacent to the side surface 11c. In this modification, in the piezoelectric layer 14c, the internal electrodes 124Ea and 124Eb are physically and electrically connected by a connecting portion 154b. The connecting portion 154b extends, for example, in the diagonal direction of the one diagonal. In this modification, in the piezoelectric layer 14e, the internal electrodes 124Ec and 124Ed are physically and electrically connected by a connecting portion 154c. The connecting portion 154c extends, for example, in the diagonal direction of the other diagonal.

[0124] In this modification, in the piezoelectric layer 14d, the internal electrodes 12F and 12G are physically and electrically connected by a connecting portion 154d. The connecting portion 154d extends, for example, in the diagonal direction of the one diagonal. In this modification, in the piezoelectric layer 14f, the internal electrodes 12C and 12D are physically and electrically connected by a connecting portion 154e. The connecting portion 154e extends, for example, in the diagonal direction of the other diagonal.

[0125] In this embodiment, the piezoelectric body 11 includes connecting conductors 164a, 164b, 164c, 164d, 164e1, 164e2, 164e3, 164e4, 164f, 164g, 164h, and 164i. The connecting conductors 164a, 164c, 164e1, 164e3, 164f, and 164h are exposed on the side surface 11d. The connecting conductors 164b, 164d, 164e2, 164e4, 164g, and 164i are exposed on the side surface 11c.

[0126] The connecting conductors 164a, 164b, 164c, and 164d are disposed on the piezoelectric layer 14b and the piezoelectric layer 14f. In the piezoelectric layer 14b and the piezoelectric layer 14f, the connecting conductors 164a and 164c are exposed on the side surface 11d at different positions in the third direction D3, for example. The connecting conductors 164b and 164d are exposed on the side surface 11c at different positions in the third direction D3, for example. The connecting conductors 164a and 164d are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example. The connecting conductors 164b and 164c are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example.

[0127] In this modification, the connecting conductor 164a is connected to the edge of the internal electrode 12A closer to the side surface 11d, for example, at a position closer to the end face 11f of the internal electrode 12A in the third direction D3. The connecting conductor 164b is connected to the edge of the internal electrode 12B closer to the side surface 11c, for example, at a position closer to the end face 11e of the internal electrode 12B in the third direction D3. The connecting conductor 164c is connected to the edge of the internal electrode 12C closer to the side surface 11d, for example, at a position closer to the end face 11e of the internal electrode 12C in the third direction D3. The connecting conductor 164d is connected to the edge of the internal electrode 12D closer to the side surface 11c, for example, at a position closer to the end face 11f of the internal electrode 12D in the third direction D3.

[0128] The connecting conductors 164e1, 164e2, 164e3, and 164e4 are disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. In the piezoelectric layer 14c and the piezoelectric layer 14e, the connecting conductors 164e1 and 164e3 are exposed on the side surface 11d at different positions in the third direction D3, for example. The connecting conductors 164e2 and 164e4 are exposed on the side surface 11c at different positions in the third direction D3, for example. The connecting conductors 164e1 and 164e4 are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example. The connecting conductors 164e2 and 164e3 are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example.

[0129] In the piezoelectric layers 14c and 14e, the connecting conductor 164e1 is connected to the internal electrode 124Ea. The connecting conductor 164e1 is connected to the edge of the internal electrode 124Ea closer to the side surface 11d, for example, at a position closer to the end face 11e of the internal electrode 124Ea in the third direction D3. The connecting conductor 164e1 and the internal electrode 124Ea are connected, for example, physically and electrically. In the piezoelectric layers 14c and 14e, the connecting conductor 164e2 is connected to the internal electrode 124Eb. The connecting conductor 164e2 is connected to the edge of the internal electrode 124Eb closer to the side surface 11c, for example, at a position closer to the end face 11f of the internal electrode 124Eb in the third direction D3. The connecting conductor 164e2 and the internal electrode 124Eb are connected, for example, physically and electrically.

[0130] In the piezoelectric layers 14c and 14e, the connecting conductor 164e3 is connected to the internal electrode 124Ec. The connecting conductor 164e3 is connected to the edge of the internal electrode 124Ec closer to the side surface 11d, for example, at a position closer to the end face 11f of the internal electrode 124Ec in the third direction D3. The connecting conductor 164e3 and the internal electrode 124Ec are connected, for example, physically and electrically. In the piezoelectric layers 14c and 14e, the connecting conductor 164e4 is connected to the internal electrode 124Ed. The connecting conductor 164e4 is connected to the edge of the internal electrode 124Ed closer to the side surface 11c, for example, at a position closer to the end face 11e of the internal electrode 124Ed in the third direction D3. The connecting conductor 164e4 and the internal electrode 124Ed are connected, for example, physically and electrically.

[0131] The connecting conductors 164f, 164g, 164h, and 164i are disposed on the piezoelectric layer 14d. In the piezoelectric layer 14d, the connecting conductors 164f and 164h are exposed on the side surface 11d at different positions in the third direction D3, for example. The connecting conductors 164g and 164i are exposed on the side surface 11c at different positions in the third direction D3, for example. The connecting conductors 164f and 164i are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example. The connecting conductors 164h and 164g are exposed on corresponding sides of the pair of side surfaces 11c and 11d at the same positions in the third direction D3, for example.

[0132] In this modification, the connecting conductor 164f is connected to the edge of the internal electrode 12F closer to the side surface 11d, for example, at a position closer to the end face 11f of the internal electrode 12F in the third direction D3. The connecting conductor 164g is connected to the edge of the internal electrode 12G closer to the side surface 11c, for example, at a position closer to the end face 11e of the internal electrode 12G in the third direction D3. The connecting conductor 164h is connected to the edge of the internal electrode 12H closer to the side surface 11d, for example, at a position closer to the end face 11e of the internal electrode 12H in the third direction D3. The connecting conductor 164i is connected to the edge of the internal electrode 12I closer to the side surface 11c, for example, at a position closer to the end face 11f of the internal electrode 12I in the third direction D3.

[0133] As shown in FIGS. 19 and 20 , the internal electrodes 12A, 12B, 12C, and 12D arranged on the piezoelectric layer 14b face the internal electrode 124E arranged on the piezoelectric layer 14c through a portion of the piezoelectric body 11. In this modification, the internal electrode 12A arranged on the piezoelectric layer 14b faces the internal electrode 124Ea arranged on the piezoelectric layer 14c through the piezoelectric layer. The internal electrode 12B arranged on the piezoelectric layer 14b faces the internal electrode 124Eb arranged on the piezoelectric layer 14c through the piezoelectric layer. The internal electrode 12C arranged on the piezoelectric layer 14b faces the internal electrode 124Ec arranged on the piezoelectric layer 14c through the piezoelectric layer. The internal electrode 12D arranged on the piezoelectric layer 14b faces the internal electrode 124Ed arranged on the piezoelectric layer 14c through the piezoelectric layer.

[0134] The internal electrode 124E arranged on the piezoelectric layer 14c faces the internal electrodes 12F, 12G, 12H, and 12I arranged on the piezoelectric layer 14d through a portion of the piezoelectric body 11. In this modification, the internal electrode 124Ea arranged on the piezoelectric layer 14c faces the internal electrode 12F arranged on the piezoelectric layer 14d through the piezoelectric layer. The internal electrode 124Eb arranged on the piezoelectric layer 14c faces the internal electrode 12G arranged on the piezoelectric layer 14d through the piezoelectric layer. The internal electrode 124Ec arranged on the piezoelectric layer 14c faces the internal electrode 12H arranged on the piezoelectric layer 14d through the piezoelectric layer. The internal electrode 124Ed arranged on the piezoelectric layer 14c faces the internal electrode 12I arranged on the piezoelectric layer 14d through the piezoelectric layer.

[0135] The internal electrodes 12F, 12G, 12H, and 12I arranged on the piezoelectric layer 14d face the internal electrode 124E arranged on the piezoelectric layer 14e through a portion of the piezoelectric body 11. In this modification, the internal electrode 12F arranged on the piezoelectric layer 14d faces the internal electrode 124Ea arranged on the piezoelectric layer 14e through the piezoelectric layer. The internal electrode 12G arranged on the piezoelectric layer 14d faces the internal electrode 124Eb arranged on the piezoelectric layer 14e through the piezoelectric layer. The internal electrode 12H arranged on the piezoelectric layer 14d faces the internal electrode 124Ec arranged on the piezoelectric layer 14e through the piezoelectric layer. The internal electrode 12I arranged on the piezoelectric layer 14d faces the internal electrode 124Ed arranged on the piezoelectric layer 14e through the piezoelectric layer.

[0136] The internal electrode 124E arranged on the piezoelectric layer 14e faces the internal electrodes 12A, 12B, 12C, and 12D arranged on the piezoelectric layer 14f through a portion of the piezoelectric body 11. In this modification, the internal electrode 124Ea arranged on the piezoelectric layer 14e faces the internal electrode 12A arranged on the piezoelectric layer 14f through the piezoelectric layer. The internal electrode 124Eb arranged on the piezoelectric layer 14e faces the internal electrode 12B arranged on the piezoelectric layer 14f through the piezoelectric layer. The internal electrode 124Ec arranged on the piezoelectric layer 14e faces the internal electrode 12C arranged on the piezoelectric layer 14f through the piezoelectric layer. The internal electrode 124Ed arranged on the piezoelectric layer 14e faces the internal electrode 12D arranged on the piezoelectric layer 14f through the piezoelectric layer.

[0137] In this modification, the portion P1 includes the internal electrode 12C, the internal electrode 124Ec, and a piezoelectric layer sandwiched between the internal electrodes 12C and 124Ec. In the portion P1, the piezoelectric layer sandwiched between the internal electrodes 12C and 124Ec constitutes an active region. The portion P1 includes the internal electrode 12D, the internal electrode 124Ed, and a piezoelectric layer sandwiched between the internal electrodes 12D and 124Ed. In the portion P1, the piezoelectric layer sandwiched between the internal electrodes 12D and 124Ed constitutes an active region. The portion P1 includes the internal electrode 12H, the internal electrode 124Ec, and a piezoelectric layer sandwiched between the internal electrodes 12H and 124Ec. In the portion P1, the piezoelectric layer sandwiched between the internal electrodes 12H and 124Ec forms an active region. The portion P1 includes the internal electrode 12I, the internal electrode 124Ed, and a piezoelectric layer sandwiched between the internal electrodes 12I and 124Ed. In the portion P1, the piezoelectric layer sandwiched between the internal electrodes 12I and 124Ed constitutes an active region.

[0138] In this modification, the portion P2 includes the internal electrode 12A, the internal electrode 124Ea, and a piezoelectric layer sandwiched between the internal electrodes 12A and 124Ea. In the portion P2, the piezoelectric layer sandwiched between the internal electrodes 12A and 124Ea constitutes an active region. Portion P2 includes the internal electrode 12B, the internal electrode 124Eb, and a piezoelectric layer sandwiched between the internal electrodes 12B and 124Eb. In portion P2, the piezoelectric layer sandwiched between the internal electrode 12B and that portion of the internal electrode 124Eb forms an active region. The portion P2 includes the internal electrode 12F, the internal electrode 124Ea, and a piezoelectric layer sandwiched between the internal electrodes 12F and 124Ea. In the portion P2, the piezoelectric layer sandwiched between the internal electrodes 12F and 124Ea forms an active region. Portion P2 includes the internal electrode 12G, the internal electrode 124Eb, and a piezoelectric layer sandwiched between the internal electrodes 12G and 124Eb. In portion P2, the piezoelectric layer sandwiched between the internal electrode 12G and that portion of the internal electrode 124Eb forms an active region.

[0139] 17, the external electrodes 13 include external electrodes 134A, 134B, 134C, 134D, 134E, 134F, 134G, and 134H. The external electrodes 134A, 134B, 134C, 134D, 134E, 134F, 134G, and 134H have a rectangular shape when viewed from the second direction D2. In this modification, the longitudinal direction of the external electrodes 134A, 134B, 134C, 134D, 134E, 134F, 134G, and 134H corresponds to the first direction D1. The lateral direction of the external electrodes 134A, 134B, 134C, 134D, 134E, 134F, 134G, and 134H corresponds to the third direction D3. The longitudinal direction of the external electrodes 134A, 134B, 134C, 134D, 134E, 134F, 134G, and 134H may correspond to the third direction D3. The lateral direction of the external electrodes 134A, 134B, 134C, 134D, 134E, 134F, 134G, and 134H may correspond to the first direction D1.

[0140] The external electrodes 134A, 134B, 134C, and 134G are arranged on the side surface 11c. The external electrodes 134A, 134B, 134C, and 134G are lined up in this order, for example, in the third direction D3, in the direction from end surface 11e toward end surface 11f. The external electrodes 134D, 134E, 134F, and 134H are arranged on the side surface 11d. The external electrodes 134D, 134E, 134F, and 134H are lined up in this order, for example, in the third direction D3, in the direction from end surface 11e toward end surface 11f.

[0141] In this modification, the external electrode 134A is connected to the connecting conductor 164e4 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 134A to the internal electrode 124Ed disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. The external electrode 134B is connected to the connecting conductor 164d arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and to the connecting conductor 164i arranged on the piezoelectric layer 14d, thereby electrically connecting the external electrode 134B to the internal electrode 12D arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and to the internal electrode 12I arranged on the piezoelectric layer 14d. The external electrode 134C is connected to a connecting conductor 164b disposed on the piezoelectric layer 14b and the piezoelectric layer 14f and to a connecting conductor 164g disposed on the piezoelectric layer 14d, thereby electrically connecting the external electrode 134C to the internal electrode 12B disposed on the piezoelectric layer 14b and the piezoelectric layer 14f and the internal electrode 12G disposed on the piezoelectric layer 14d. In this modification, the external electrode 134G is connected to the connecting conductor 164e2 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 134G to the internal electrode 124Eb disposed on the piezoelectric layer 14c and the piezoelectric layer 14e.

[0142] The external electrode 134D is connected to the connecting conductor 164e1 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 134D to the internal electrode 124Ea disposed on the piezoelectric layer 14c and the piezoelectric layer 14e. The external electrode 134E is connected to the connecting conductor 164a disposed on the piezoelectric layer 14b and the piezoelectric layer 14f and to the connecting conductor 164f disposed on the piezoelectric layer 14d, thereby electrically connecting the external electrode 134E to the internal electrode 12A disposed on the piezoelectric layer 14b and the piezoelectric layer 14f and to the internal electrode 12F disposed on the piezoelectric layer 14d. The external electrode 134F is connected to the connecting conductor 164c arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and to the connecting conductor 164h arranged on the piezoelectric layer 14d, thereby electrically connecting the external electrode 134F to the internal electrode 12C arranged on the piezoelectric layer 14b and the piezoelectric layer 14f and the internal electrode 12H arranged on the piezoelectric layer 14d. In this modification, the external electrode 134H is connected to the connecting conductor 164e3 disposed on the piezoelectric layer 14c and the piezoelectric layer 14e, thereby electrically connecting the external electrode 134H to the internal electrode 124Ec disposed on the piezoelectric layer 14c and the piezoelectric layer 14e.

[0143] In this modification, the amplifier 20 is electrically connected to the external electrode 134C. The oscillator 30 is electrically connected to the external electrode 134B. In this modification, the oscillator 30 is also electrically connected to the external electrodes 134A and 134G. This causes the oscillator 30 to apply a voltage to the portion P1. In this modification, the oscillator 30 applies a voltage to the internal electrode 12C and the internal electrode 124E, the internal electrode 12D and the internal electrode 124E, the internal electrode 12H and the internal electrode 124E, and the internal electrode 12I and the internal electrode 124E.

[0144] Next, the configuration of a fifth modified example of the input device ID according to this embodiment will be described with reference to Figs. 21 and 22. Fig. 21 is a perspective view of a piezoelectric element. Fig. 22 is a diagram showing the cross-sectional configuration of the piezoelectric element. Hatching has been omitted in Fig. 22 to clearly show each part. This modified example differs from the above-described embodiment in terms of the configuration of the piezoelectric element 10. Below, the differences between the above-described embodiment and this modified example will be mainly described.

[0145] In this modification, the piezoelectric element 10 includes electrodes 17a, 17b and an electrode 18 instead of the internal electrode 12 and the external electrode 13. The electrodes 17a, 17b and the electrode 18 are rectangular in shape. Electrodes 17a, 17b and electrode 18 are disposed on the piezoelectric body 11. As shown in Fig. 21 , in this modification, electrodes 17a, 17b are disposed on the main surface 11a of the piezoelectric body 11. When viewed from the first direction D1, electrode 17a is disposed closer to the end surface 11f than the center of the main surface 11a in the third direction D3. When viewed from the first direction D1, electrode 17b is disposed closer to the end surface 11e than the center of the main surface 11a in the third direction D3.

[0146] The electrode 18 is disposed on the principal surface 11b of the piezoelectric body 11. When viewed from the first direction D1, the electrode 18 has a rectangular shape that is slightly smaller than the rectangular shape of the piezoelectric body 11. In this modification, the electrode 18 includes an electrode 18a and an electrode 18b. When viewed from the first direction D1, the electrode 18a is disposed closer to the end face 11f than the center of the principal surface 11b in the third direction D3. When viewed from the first direction D1, the electrode 18b is disposed closer to the end face 11e than the center of the principal surface 11b in the third direction D3. In this modification, the electrodes 18a and 18b are integral with each other.

[0147] 22, electrodes 17a and 17b arranged on principal surface 11a face electrode 18 arranged on principal surface 11b across a part of piezoelectric body 11. In this modification, electrode 17a arranged on principal surface 11a faces electrode 18a arranged on principal surface 11b across a piezoelectric layer. Electrode 17b arranged on principal surface 11a faces electrode 18b arranged on principal surface 11b across a piezoelectric layer.

[0148] In this modification, portion P1 includes electrode 17a, electrode 18a, and a piezoelectric layer sandwiched between electrode 17a and electrode 18a. In portion P1, the piezoelectric layer sandwiched between electrode 17a and electrode 18a forms an active region. In this modification, portion P2 includes electrode 17b, electrode 18b, and a piezoelectric layer sandwiched between electrodes 17b and 18b. In portion P2, the piezoelectric layer sandwiched between electrodes 17b and 18b constitutes an active region.

[0149] In this modification, the amplifier 20 is electrically connected to the electrode 17b. The oscillator 30 is electrically connected to the electrode 17a. In this modification, the oscillator 30 is also electrically connected to the electrode 18. This causes the oscillator 30 to apply a voltage to the portion P1. In this modification, the oscillator 30 applies a voltage to the electrode 17a and the electrode 18.

[0150] Next, the configuration of a sixth modified example of the input device ID according to this embodiment will be described with reference to Figs. 23 and 24. Fig. 23 is a perspective view of a piezoelectric element. Fig. 24 is a diagram showing the cross-sectional configuration of the piezoelectric element. Hatching is omitted in Fig. 24 to clearly show each part. This modified example differs from the fifth modified example described above in terms of the configuration of the piezoelectric element 10. Below, the differences between this modified example and the fifth modified example described above will be mainly described.

[0151] In this modification, the piezoelectric element 10 includes electrodes 171a and 171b instead of the electrodes 17a and 17b. The electrodes 171a and 171b are, for example, rectangular in shape. 23, electrodes 171a and 171b are disposed on the principal surface 11a. In this modification, the electrode 171a is disposed closer to the side surface 11c than the center of the principal surface 11a in the second direction D2 when viewed from the first direction D1. The electrode 171b is disposed closer to the side surface 11d than the center of the principal surface 11a in the second direction D2 when viewed from the first direction D1.

[0152] In this modification, the electrode 18 includes an electrode 181a and an electrode 181b. When viewed from the first direction D1, the electrode 181a is disposed closer to the side surface 11c than the center of the main surface 11a in the second direction D2. When viewed from the first direction D1, the electrode 181b is disposed closer to the side surface 11d than the center of the main surface 11a in the second direction D2. In this modification, the electrodes 181a and 181b are integral with each other.

[0153] 24, electrodes 171a and 171b arranged on principal surface 11a face electrode 18 arranged on principal surface 11b across a portion of piezoelectric body 11. In this modification, electrode 171a arranged on principal surface 11a faces electrode 181a arranged on principal surface 11b across a piezoelectric layer. Electrode 171b arranged on principal surface 11a faces electrode 181b arranged on principal surface 11b across a piezoelectric layer.

[0154] In this modification, portion P1 includes an electrode 171a, an electrode 181a, and a piezoelectric layer sandwiched between the electrodes 171a and 181a. In portion P1, the piezoelectric layer sandwiched between the electrodes 171a and 181a forms an active region. In this modification, portion P2 includes electrode 171b, electrode 181b, and a piezoelectric layer sandwiched between electrode 171b and electrode 181b. In portion P2, the piezoelectric layer sandwiched between electrode 171b and electrode 181b forms an active region.

[0155] In this modification, the amplifier 20 is electrically connected to the electrode 171b. The oscillator 30 is electrically connected to the electrode 171a and the electrode 18. This causes the oscillator 30 to apply a voltage to the portion P1. In this modification, the oscillator 30 applies a voltage to the electrode 171a and the electrode 18.

[0156] Next, the configuration of a seventh modified example of the input device ID according to this embodiment will be described with reference to Figs. 25, 26, and 27. Fig. 25 is a perspective view of a piezoelectric element. Fig. 26 is a diagram showing the cross-sectional configuration of the piezoelectric element. Fig. 27 is a diagram showing the cross-sectional configuration of the piezoelectric element. Hatching is omitted in Figs. 26 and 27 to clearly show each part. This modified example differs from the fifth modified example described above in terms of the configuration of the piezoelectric element 10. Below, the differences between this modified example and the fifth modified example described above will be mainly described.

[0157] In this modification, the piezoelectric element 10 includes electrodes 172a, 172b, 172c, and 172d instead of the electrodes 17a and 17b. The electrodes 172a, 172b, 172c, and 172d are, for example, rectangular in shape.

[0158] As shown in FIG. 25, electrodes 172a, 172b, 172c, and 172d are arranged on the principal surface 11a. On the principal surface 11a, the electrodes 172a and 172b are arranged, for example, at one diagonal corner of the rectangular shape of the piezoelectric body 11. In this modification, the electrode 172a is arranged at the corner formed by the side surface 11d and the end surface 11e, and the electrode 172b is arranged at the corner formed by the side surface 11c and the end surface 11f. On the principal surface 11a, the electrodes 172c and 172d are arranged, for example, at the other diagonal corner of the rectangular shape of the piezoelectric body 11. In this modification, the electrode 172c is arranged at the corner formed by the side surface 11d and the end surface 11f, and the electrode 172d is arranged at the corner formed by the side surface 11c and the end surface 11e.

[0159] In this modification, the electrodes 18 include electrodes 182a, 182b, 182c, and 182d. The electrodes 182a, 182b, 182c, and 182d are arranged on the main surface 11b. On the main surface 11b, the electrodes 182a and 182b are arranged, for example, at one diagonal corner of the rectangular shape of the piezoelectric body 11. In this modification, the electrode 182a is arranged at the corner formed by the side surface 11d and the end surface 11e, and the electrode 182b is arranged at the corner formed by the side surface 11c and the end surface 11f. On the main surface 11a, the electrodes 182c and 182d are arranged, for example, at the other diagonal corner of the rectangular shape of the piezoelectric body 11. In this modification, electrode 182c is arranged at the corner formed by side surface 11d and end surface 11f, and electrode 182d is arranged at the corner formed by side surface 11c and end surface 11e. In this modification, electrodes 182a, 182b, 182c, and 182d are integrated.

[0160] As shown in FIGS. 26 and 27 , electrodes 172a, 172b, 172c, and 172d arranged on the principal surface 11a face electrode 18 arranged on the principal surface 11b across a portion of the piezoelectric body 11. In this modification, electrode 172a arranged on the principal surface 11a faces electrode 182a arranged on the principal surface 11b across a piezoelectric layer. Electrode 172b arranged on the principal surface 11a faces electrode 182b arranged on the principal surface 11b across a piezoelectric layer. Electrode 172c arranged on the principal surface 11a faces electrode 182c arranged on the principal surface 11b across a piezoelectric layer. Electrode 172d arranged on the principal surface 11a faces electrode 182d arranged on the principal surface 11b across a piezoelectric layer.

[0161] In this modification, portion P1 includes electrode 172a, electrode 182a, and a piezoelectric layer sandwiched between electrode 172a and electrode 182a. In portion P1, the piezoelectric layer sandwiched between electrode 172a and electrode 182a forms an active region. Portion P1 includes electrode 172b, electrode 182b, and a piezoelectric layer sandwiched between electrode 172b and electrode 182b. In portion P1, the piezoelectric layer sandwiched between electrode 172b and electrode 182b forms an active region.

[0162] In this modification, portion P2 includes electrode 172c, electrode 182c, and a piezoelectric layer sandwiched between electrode 172c and electrode 182c. In portion P2, the piezoelectric layer sandwiched between electrode 172c and electrode 182c forms an active region. Portion P2 includes electrode 172d, electrode 182d, and a piezoelectric layer sandwiched between electrode 172d and electrode 182d. In portion P2, the piezoelectric layer sandwiched between electrode 172d and electrode 182d forms an active region.

[0163] In this modification, the amplifier 20 is electrically connected to the electrodes 172c and 172d. The oscillator 30 is electrically connected to the electrodes 172a and 172b and the electrode 18. This causes the oscillator 30 to apply a voltage to the portion P1. In this modification, the oscillator 30 applies a voltage to the electrodes 172a and 18, and to the electrodes 172b and 18.

[0164] An example of the operation of the control unit CU will be described with reference to Fig. 28. Fig. 28 is a flowchart showing an example of control processing in the input device. In step S1, the oscillator 30 applies a voltage to the piezoelectric element 10. In this control process, the oscillator 30 applies the voltage to a portion P1 of the piezoelectric element 10. For example, when the oscillator 30 receives an application command from the processing unit 50, it applies a voltage to the portion P1. When the processing unit 50 receives information indicating that the piezoelectric element 10 has received a force from an operating object, for example, from a sensor (not shown), it outputs the application command to the oscillator 30. The processing unit 50 may output the application command to the oscillator 30 in response to a request from a user of the control unit CU.

[0165] In step S2, the processing unit 50 acquires a signal output from the operation unit OU. In this control process, the processing unit 50 acquires a digital signal output from the converter 40. That is, in step S2, the processing unit 50 acquires voltage data in which the signal output from the operation unit OU has been converted into digital data.

[0166] In step S3, the processing unit 50 acquires information about the force received from the operating object. In this control process, step S3 includes steps S31 and S32. In step S31, the processing unit 50 compares a value based on the signal output from the operation unit OU with a reference value. In this control process, the processing unit 50 compares the value based on the signal output from the operation unit OU with the reference value to find the difference between the value based on the signal output from the operation unit OU and the reference value.

[0167] In step S32, the processing unit 50 acquires information about the force applied from the operating object based on the result of the comparison. In this control process, the processing unit 50 references information indicating the relationship between the difference calculated in step S31 and a value based on the magnitude of the force applied from the operating object, and acquires a value corresponding to the calculated difference. Next, the processing unit 50 acquires the acquired value based on the magnitude of the force applied from the operating object as information about the force applied from the operating object. That is, in this control method, the processing unit 50 acquires information about the force applied from the operating object based on the difference between a value based on the signal output from the operation unit OU and a reference value.

[0168] As described above, the present control method discloses a control method for the input device ID, which includes applying a voltage to part P1, acquiring a signal output from the operation unit OU, and acquiring information regarding the force received from the operating body based on the acquired signal.

[0169] In this control method, a voltage is applied to portion P1. When the voltage is applied to portion P1, portion P1 is displaced. This causes the displacement of portion P1 to be transmitted to portion P2, which then changes. When the piezoelectric element 10 receives a force from the operating body, a restraining force corresponding to the force acts on the piezoelectric body 11, which includes portions P1 and P2. Therefore, the ease with which portion P2 is displaced changes depending on the force the piezoelectric element 10 receives from the operating body. In other words, when the piezoelectric element 10 receives a force from the operating body, the displacement of portion P2 changes depending on the force. As the displacement of portion P2 changes, the charge generated in portion P2 also changes. In this control method, a voltage is applied to the portion P1 that is included in the piezoelectric body 11 together with the portion P2, so the displacement of the portion P1 due to the applied voltage is more easily transmitted to the portion P2 than when the portions P1 and P2 are included in separate piezoelectric bodies. Therefore, the displacement of the portion P2 changes appropriately according to the force received from the operating object. As a result of the above, this control method improves the accuracy of information relating to the force received from the operating object.

[0170] In this control method, acquiring information regarding the force received from the operating body includes comparing a value based on a signal output from the operating unit with a reference value, and acquiring information regarding the force received from the operating body based on the result of the comparison. By comparing the value based on the signal output from the operation unit OU with the reference value, it is possible to accurately capture the change in the force that the piezoelectric element 10 receives from the operating body. Therefore, this control method further improves the accuracy of the information related to the force that is received from the operating body.

[0171] In the control method, the comparing step includes determining the difference between a value based on the signal output from the operating unit OU and a reference value. The difference between the value based on the signal output from the operation unit OU and the reference value indicates the amount of change from the reference value. By determining the amount of change from the reference value, the change in the force that the piezoelectric element 10 receives from the operating body can be captured more reliably and accurately. Therefore, this control method more reliably improves the accuracy of information related to the force received from the operating body.

[0172] The above describes embodiments and modifications of the present invention, but the present invention is not necessarily limited to the above-described embodiments and modifications, and various modifications are possible without departing from the spirit of the present invention.

[0173] In the above-described embodiment and modified examples, the control unit CU includes the oscillator 30, but the control unit CU may not include the oscillator 30. In other words, the input device ID may not include the oscillator 30. When the input device ID does not include the oscillator 30, another device different from the input device ID may include the oscillator 30.

[0174] In the above-described embodiment and modified examples, the control unit CU compares a value based on a signal output from the operation unit OU with a reference value, and acquires information about the force applied from the operating object based on the comparison result. However, the control unit CU may acquire information about the force applied from the operating object without comparing a value based on a signal output from the operation unit OU with the reference value. When the control unit CU acquires information about the force applied from the operating object without comparing a value based on the signal output from the operation unit OU with a reference value, the processing unit 50 may acquire information about the force applied from the operating object, for example, as follows. First, the processing unit 50 may refer to information indicating the relationship between a value based on the signal output from the operation unit OU and a value based on the magnitude of the force applied from the operating object. Next, the processing unit 50 may acquire a value corresponding to the value based on the signal output from the operation unit OU. Next, the acquired value based on the magnitude of the force applied from the operating object may be acquired as information about the force applied from the operating object.

[0175] In the above-described embodiment and modified examples, the control unit CU acquires information about the force applied from the operating object based on the difference between a value based on the signal output from the operation unit OU and a reference value. However, the process by which the control unit CU acquires information about the force applied from the operating object is not limited to the process described above. For example, the control unit CU may acquire information about the force applied from the operating object based on the ratio between the value based on the signal output from the operation unit OU and the reference value.

[0176] When the control unit CU acquires information about the force applied from the operating object based on the ratio between a value based on the signal output from the operation unit OU and a reference value, the processing unit 50 may acquire the information about the force applied from the operating object, for example, as follows. First, the processing unit 50 may calculate the ratio between the value based on the signal output from the operation unit OU and the reference value. Next, the processing unit 50 may refer to information indicating the relationship between the calculated ratio and a value based on the magnitude of the force applied from the operating object, and acquire a value corresponding to the calculated ratio. Next, the acquired value based on the magnitude of the force applied from the operating object may be acquired as information about the force applied from the operating object.

[0177] As can be understood from the above description of the embodiments and modifications, the present specification includes disclosure of the following aspects. (Appendix 1) an operation unit including a piezoelectric element that receives a force from an operation body, the piezoelectric element including one piezoelectric body including a first portion that is displaced by application of a voltage and a second portion that generates an electric charge by the displacement, and that outputs a signal according to the electric charge generated in the second portion; a control unit that acquires information about a force applied from the operating object based on the signal output from the operation unit. (Appendix 2) The input device described in Appendix 1, wherein the control unit compares a value based on the signal output from the operation unit with a reference value, and obtains the information regarding the force received from the operating body based on the result of the comparison. (Appendix 3) 3. The input device according to claim 2, wherein the reference value is a value based on the signal output from the operation unit in an initial state where no force is applied from the operation object. (Appendix 4) The input device according to claim 2 or 3, wherein the control unit acquires the information regarding the force received from the operating body based on the difference between a value based on the signal output from the operation unit and the reference value. (Appendix 5) The input device according to any one of appendices 1 to 4, wherein the operation unit includes an amplifier that amplifies the voltage generated in the second portion, and outputs the voltage amplified by the amplifier as a signal corresponding to the charge generated in the second portion. (Appendix 6) The input device according to any one of appendices 1 to 5, wherein the control unit includes a converter that converts the signal output from the operation unit into a digital signal, and obtains information regarding the force received from the operating body based on the digital signal converted by the converter. (Appendix 7) An input device according to any one of appendices 1 to 6, wherein the piezoelectric element includes a first internal electrode and a second internal electrode that are included in the first portion and face each other, and a third internal electrode and a fourth internal electrode that are included in the second portion and face each other. (Appendix 8) 8. The input device of claim 7, wherein the second internal electrode and the fourth internal electrode are located in the same layer and are integral with each other. (Appendix 9) 9. The input device according to claim 7, wherein the first internal electrode and the third internal electrode are located in the same layer. (Appendix 10) 11. The input device according to any one of claims 1 to 10, wherein the control unit outputs the voltage to be applied to the first part. (Appendix 11) A method for controlling an input device, comprising: the input device includes a piezoelectric element that receives a force from an operating body, the piezoelectric element including one piezoelectric body that includes a first portion that is displaced by application of a voltage and a second portion that generates an electric charge by the displacement, and an operation unit that outputs a signal according to the electric charge generated in the second portion; applying a voltage to the first portion; acquiring the signal output from the operation unit; and acquiring information relating to the force applied from the operating object based on the acquired signal. (Appendix 12) The acquiring of the information regarding the force received from the operating object includes: comparing a value based on the signal output from the operation unit with a reference value; and acquiring the information regarding the force received from the operating object based on a result of the comparison. (Appendix 13) 13. The control method for an input device according to claim 12, wherein the comparing step includes determining a difference between a value based on the signal output from the operation unit and the reference value. [Explanation of symbols]

[0178] 10...piezoelectric element, 11...piezoelectric body, 20...amplifier, 40...converter, CU...control unit, ID...input device, OU...operation unit.

Claims

1. an operation unit including a piezoelectric element that receives a force from an operation body, the piezoelectric element including one piezoelectric body including a first portion that is displaced by application of a voltage and a second portion that generates an electric charge by the displacement, and that outputs a signal according to the electric charge generated in the second portion; a control unit that acquires information about a force applied from the operating object based on the signal output from the operation unit.

2. The input device according to claim 1 , wherein the control unit compares a value based on the signal output from the operation unit with a reference value, and acquires the information regarding the force applied from the operation object based on a result of the comparison.

3. The input device according to claim 2 , wherein the reference value is a value based on the signal output from the operation unit in an initial state in which no force is applied from the operation object.

4. The input device according to claim 2 , wherein the control unit acquires the information regarding the force applied from the operating object based on a difference between the value based on the signal output from the operation unit and the reference value.

5. The input device according to any one of claims 1 to 3, wherein the operation unit includes an amplifier that amplifies the voltage generated in the second portion, and outputs the voltage amplified by the amplifier as a signal corresponding to the charge generated in the second portion.

6. The input device according to any one of claims 1 to 3, wherein the control unit includes a converter that converts the signal output from the operation unit into a digital signal, and obtains information regarding the force received from the operating body based on the digital signal converted by the converter.

7. The input device according to any one of claims 1 to 3, wherein the piezoelectric element includes a first internal electrode and a second internal electrode that are included in the first portion and that face each other, and a third internal electrode and a fourth internal electrode that are included in the second portion and that face each other.

8. The input device according to claim 7 , wherein the second internal electrode and the fourth internal electrode are located in the same layer and are integral with each other.

9. The input device according to claim 7 , wherein the first internal electrode and the third internal electrode are located in the same layer.

10. The input device according to any one of claims 1 to 3, wherein the control unit outputs the voltage to be applied to the first portion.

11. A method for controlling an input device, comprising: the input device includes a piezoelectric element that receives a force from an operating body, the piezoelectric element including one piezoelectric body that includes a first portion that is displaced by application of a voltage and a second portion that generates an electric charge by the displacement, and an operation unit that outputs a signal according to the electric charge generated in the second portion; applying a voltage to the first portion; acquiring the signal output from the operation unit; and acquiring information relating to the force applied from the operating object based on the acquired signal.

12. The acquiring of the information regarding the force received from the operating object includes: comparing a value based on the signal output from the operation unit with a reference value; The method of controlling an input device according to claim 11 , further comprising: acquiring the information regarding the force applied from the operating object based on a result of the comparison.

13. The method for controlling an input device according to claim 12, wherein the comparing step includes determining a difference between a value based on the signal output from the operation unit and the reference value.

Images