WO2018225407A1

WO2018225407A1 - Pressed position detection sensor and electronic apparatus

Info

Publication number: WO2018225407A1
Application number: PCT/JP2018/016397
Authority: WO
Inventors: 大寺　昭三
Original assignee: 株式会社村田製作所
Priority date: 2017-06-05
Filing date: 2018-04-23
Publication date: 2018-12-13
Also published as: JP6620912B2; JPWO2018225407A1

Abstract

The present invention is provided with: a piezoelectric film (14) that deforms due to a pressing operation performed by a user; a first electrode (11) formed on a first main surface of the piezoelectric film (14); a second electrode (12) formed on the first main surface of the piezoelectric film (14); and a reference electrode (13) formed on a second main surface of the piezoelectric film (14). The first electrode (11) and the second electrode (12) are disposed by being aligned with each other in Z direction, and the width difference of the first electrode (11) in the first direction (Z), and the width difference of the second electrode (12) in the first direction are different from each other in second direction (Y) perpendicular to the Z direction.

Description

Push position detection sensor and electronic device

An embodiment of the present invention relates to a push position detection sensor and an electronic device that detect a push position on a panel.

In Patent Literature 1, panels constituting various display screens, long piezoelectric elements each fixed along at least two sides intersecting the peripheral edge of the panel, and the above-described pressure caused by pressing force on the panel are disclosed. There is disclosed a touch panel provided with a pressed position calculating means for calculating a pressed position in the panel based on an output of a piezoelectric element. In the touch panel described in Patent Document 1, the pressing position on the panel is detected using a long piezoelectric element fixed along the periphery of the panel constituting the display screen.

JP 2007-86990 A

In the touch panel described in Patent Document 1, it is necessary that the location where the piezoelectric element is attached is uniformly deformed at any position. For example, if the location where the piezoelectric element is attached varies depending on the position, the voltage generated even when pressed with the same strength is affected by the deformation. Further, even if any position is uniformly deformed at the location where the piezoelectric element is pasted, the generated voltage may be affected by the pressing speed of the user or the like.

Therefore, an object of an embodiment of the present invention is to provide a push position detection sensor and an electronic apparatus that can detect a position where a push operation is received without being affected by the degree of deformation or the push speed.

A pressing position detection sensor according to an embodiment of the present invention includes a piezoelectric film that is deformed by a pressing operation from a user, a first electrode formed on a first main surface of the piezoelectric film, and the first electrode of the piezoelectric film. A second electrode formed on the main surface, and a reference electrode formed on the second main surface of the piezoelectric film, the first electrode and the second electrode are arranged side by side in the first direction, The difference in width between the first electrode and the second electrode in the first direction is different from each other along a second direction perpendicular to the first direction.

In this configuration, when the piezoelectric film is deformed by a pressing operation, the first electrode and the second electrode arranged side by side in the first direction simultaneously output a voltage. The voltage output from the first electrode and the second electrode corresponds to the area of each electrode. The difference in width between the first electrode and the second electrode in the first direction is different from each other along a second direction perpendicular to the first direction. Regardless of the position at which the pressing operation in the second direction is received, the difference in width between the positions at which the pressing operation is received at the first electrode and the second electrode is different. Accordingly, the first electrode and the second electrode output voltages corresponding to different areas. Therefore, by calculating the ratio of the voltage output from the first electrode to the voltage output from the second electrode, the position where the pressing operation is received is detected without being affected by the degree of deformation or the pressing speed. it can

According to one embodiment of the present invention, it is possible to detect the position where the pressing operation is received without being affected by the degree of deformation or the pressing speed.

FIG. 1A is a perspective view of an electronic apparatus including a push position detection sensor according to the first embodiment. FIG. 1B is a view for explaining the housing according to the first embodiment. FIG. 2 is a view for explaining a piezoelectric element corresponding to a portion surrounded by a broken line ellipse A1 in FIG. 3A is an exploded perspective view of the piezoelectric element according to the first embodiment, and FIG. 3B is a sectional view thereof. FIG. 4 is a diagram for explaining electrodes corresponding to a portion surrounded by a broken-line ellipse A1 in FIG. FIG. 5 is a view for explaining the piezoelectric film according to the first embodiment. FIG. 6A is a diagram for explaining the relationship between the position where the pressing operation of the first electrode and the second electrode according to the first embodiment is received and the generated voltage. FIG. 6B is a diagram for explaining the relationship between the ratio of the generated voltage in the first electrode and the second electrode and the position where the pressing operation is received. FIGS. 7A to 7D are views for explaining modifications of the first electrode and the second electrode according to the first embodiment. FIGS. 8A to 8D are views for explaining modifications of the first electrode and the second electrode according to the first embodiment. FIG. 9A is a view for explaining the first electrode and the second electrode of the push position detection sensor according to the second embodiment. FIG. 9B is a diagram for explaining the relationship between the ratio of the generated voltage in the first electrode and the second electrode according to the second embodiment and the position where the pressing operation is received. FIG. 10 is a diagram for explaining the relationship between the ratio of the generated voltage in the first electrode and the second electrode according to the example and the reference example and the position where the pressing operation is received. FIG. 11 is a conceptual diagram for explaining a push position detection sensor according to the third embodiment. FIG. 12A is a view for explaining the first electrode and the second electrode of the push position detection sensor according to the fourth embodiment. FIG. 12B is a diagram for explaining the positional relationship between the position to receive the pressing operation and the piezoelectric film according to the fourth embodiment. FIG. 12C is a diagram for explaining the relationship between the ratio of the generated voltage in the first electrode and the second electrode and the position where the pressing operation is received. FIGS. 13A to 13C are diagrams for explaining a modification according to the fourth embodiment. FIG. 14A is a view for explaining the first electrode and the second electrode of the push position detection sensor according to the fifth embodiment. FIG. 14B is a view for explaining the piezoelectric film according to the fifth embodiment. FIG. 14C is a diagram for explaining the relationship between the generated voltage in the first electrode and the second electrode and the position where the pressing operation is received. FIG. 15A and FIG. 15B are plan views of another example of the electronic apparatus including the push position detection sensor according to the first embodiment. FIG. 16A is a view for explaining the first electrode and the second electrode of the push position detection sensor according to the sixth embodiment. FIG. 16B and FIG. 16C are diagrams for explaining the relationship between the value based on the generated voltage in the first electrode and the second electrode according to the sixth embodiment and the position where the pressing operation is received.

FIG. 1A is a perspective view of an electronic device 1 including a push position detection sensor 100 according to the first embodiment. FIG. 1B is a diagram for explaining the housing 2 according to the first embodiment. FIG. 2 is a diagram for explaining the piezoelectric element 10 corresponding to a portion surrounded by a broken-line ellipse A1 in FIG. FIG. 2 is a view of the housing 2 as seen from the inside. Note that the electronic device 1 illustrated in FIG. 1A is merely an example, and is not limited thereto, and can be changed as appropriate according to specifications.

As shown in FIGS. 1 (A) and 1 (B), the electronic apparatus 1 includes a substantially rectangular parallelepiped housing 2 having an open top surface. The electronic device 1 includes a flat surface panel 4 disposed in an opening on the upper surface of the housing 2. The front panel 4 functions as an operation surface on which a user performs a touch operation using a finger or a pen. The housing 2 includes a side surface portion 3 and a bottom surface portion 7. Below, the width direction (horizontal direction) of the housing | casing 2 is set to X direction, a length direction (vertical direction) is set to Y direction, and the thickness direction is demonstrated as Z direction.

The first pressing portion 51, the second pressing portion 52, and the third pressing portion 53 are formed on the side surface portion 3. In the present embodiment, the first pressing portion 51, the second pressing portion 52, and the third pressing portion 53 are rectangular in plan view, and are formed side by side in the Y direction on the YZ plane. Moreover, in this embodiment, although the three press parts are formed, it is not restricted to this, The press part should just be formed 1 or more. The first pressing portion 51, the second pressing portion 52, and the third pressing portion 53 may be formed at locations other than the YZ plane, or may be formed at the bottom surface portion 7 or the front panel 4. Good. For example, you may be made into the part enclosed by broken-line ellipse A2 of FIG. Further, for example, by arranging the first pressing portion 51 and the like side by side around the display portion of the front panel 4, that is, surrounding the periphery of the display portion, it is possible to detect which position on the display portion is pressed. Can do.

The first pressing portion 51, the second pressing portion 52, and the third pressing portion 53 are provided on the side surface portion 3 by color-coding a part of the side surface portion 3, adding a mark, or forming a groove around the side portion 3. It is distinguished from the part. Moreover, the shape of the 1st press part 51, the 2nd press part 52, and the 3rd press part 53 is not restricted to a rectangular shape, Another shape, such as circular, a polygon, or a triangular shape, may be sufficient. Furthermore, the 1st press part 51, the 2nd press part 52, and the 3rd press part 53 are not limited to aligning in a Y direction, For example, in the state diagonally arranged with respect to the state aligned in a Z direction, or a Y direction There may be.

As shown in FIG. 1B, a push position detection sensor 100 is formed inside the housing 2. Since the push position detection sensor 100 is formed inside the housing 2, the push position detection sensor 100 is excellent in durability because it is not directly subjected to friction caused by a pressing operation. Moreover, it is not necessary to provide a through-hole in the side part 3 so that a mechanical switch may be installed. For this reason, the housing 2 can be thinned without requiring a complicated structure, and foreign matters such as moisture and dust can be prevented from entering the housing 2 from the outside through the through holes.

The push position detection sensor 100 includes the piezoelectric element 10 and the detection unit 18. The piezoelectric element 10 is disposed on the inner side 8 of the side surface portion 3. The push position detection sensor 100 may be formed outside the housing 2.

In FIG. 2, the 1st press part 51, the 2nd press part 52, and the 3rd press part 53 are shown by the dotted line. As shown in FIG. 2, the piezoelectric element 10 is disposed at a position corresponding to the first pressing portion 51, the second pressing portion 52, and the third pressing portion 53 with the side surface portion 3 of the housing 2 interposed therebetween. . The detection unit 18 is disposed inside the housing 2 and is connected to the piezoelectric element 10 by a wiring (not shown).

When the user performs a touch operation on the first pressing portion 51, the second pressing portion 52, and the third pressing portion 53 using a finger or a pen, pressure is transmitted to the piezoelectric element 10. For this reason, the piezoelectric element 10 outputs a voltage corresponding to the operation received by the first pressing part 51, the second pressing part 52, and the third pressing part 53. The detector 18 detects the voltage output from the piezoelectric element 10. The detection unit 18 may be at any position as long as it is inside the housing 2.

3A is an exploded perspective view of the piezoelectric element 10 according to the first embodiment, and FIG. 3B is a cross-sectional view thereof. As shown in FIGS. 3A and 3B, the piezoelectric element 10 includes a first electrode 11, a second electrode 12, a reference electrode 13, and a piezoelectric film 14. 3A, illustration of the piezoelectric element 10 other than the first electrode 11, the second electrode 12, the reference electrode 13, and the piezoelectric film 14 is omitted.

The first electrode 11 and the second electrode 12 are arranged on the same plane. The piezoelectric film 14 is laminated on the reference electrode 13, and the first electrode 11 and the second electrode 12 are laminated on the piezoelectric film 14. That is, the first electrode 11 and the second electrode 12 are formed on the first main surface 141 of the piezoelectric film 14, and the reference electrode 13 is formed on the second main surface 142 of the piezoelectric film 14. The reference electrode 13 and the piezoelectric film 14 are formed in substantially the same shape.

When the piezoelectric element 10 is viewed in plan view, at least one of the reference electrode 13 or the pair of the first electrode 11 and the second electrode 12 is completely overlapped with the piezoelectric film 14 in a top view or is located inward of the piezoelectric film 14 in the plane direction. Good to be. Thereby, the short circuit in the edge part of an electrode can be suppressed. Further, two sets of the reference electrode 13 and the piezoelectric film 14 may be formed in accordance with the shapes of the first electrode 11 and the second electrode 12, respectively. Thereby, since the size of the reference electrode 13 and the piezoelectric film 14 can be formed small, bulkiness can be reduced.

The first electrode 11 and the second electrode 12 are arranged side by side in the Z direction. Note that either the first electrode 11 or the second electrode 12 may be above the Z direction. The first electrode 11 has a rectangular shape, and has a uniform width in the Z direction along the Y direction. When the first electrode 11 is divided into predetermined sections along the Y direction, the area of each predetermined section is uniform. The second electrode 12 has a right triangle shape in which the width in the Z direction changes along the Y direction, that is, the area of each section changes. The second electrode 12 has two sides parallel to the Y direction or the Z direction, respectively. Since the second electrode 12 has a right triangle shape, it is easy to manufacture. As shown in the modification, the second electrode 12 is not limited to a right triangle shape as long as the area of the second electrode 12 changes along the Y direction. That is, the difference in the width in the Z direction between the first electrode 11 and the second electrode 12 is different from each other along the Y direction. The Y direction corresponds to the second direction in the present invention, and the Z direction corresponds to the first direction in the present invention.

FIG. 4 is a diagram for explaining the first electrode 11 and the second electrode 12 corresponding to the portion surrounded by the broken line ellipse A1 in FIG. FIG. 4 is a view of the housing 2 as viewed from the inside. In FIG. 4, the 1st press part 51, the 2nd press part 52, and the 3rd press part 53 are shown by the dotted line. In FIG. 4, only the first electrode 11 and the second electrode 12 of the piezoelectric element 10 are shown.

As shown in FIG. 4, the first electrode 11 has a uniform width in the Z direction along the Y direction. For this reason, the area of the 1st electrode 11 of the location corresponding to the 1st press part 51, the 2nd press part 52, and the 3rd press part 53 is respectively the same. On the other hand, the area of the second electrode 12 changes along the Y direction. For this reason, the area of the second electrode 12 at locations corresponding to the first pressing portion 51, the second pressing portion 52, and the third pressing portion 53 sequentially increases from the first pressing portion 51 toward the third pressing portion 53. To do. In addition, the 1st electrode 11 and the 2nd electrode 12 can also be suitably changed according to the shape of the 1st press part 51, the 2nd press part 52, and the 3rd press part 53. FIG.

FIG. 5 is a view for explaining the piezoelectric film 14 according to the first embodiment. FIG. 5 is a plan view of the piezoelectric film 14.

As shown in FIG. 5, the piezoelectric film 14 may be a film formed from a chiral polymer. In the first embodiment, polylactic acid (PLA), particularly L-type polylactic acid (PLLA) is used as the chiral polymer. PLLA made of a chiral polymer has a main chain with a helical structure. PLLA has piezoelectricity when uniaxially stretched and molecules are oriented. The uniaxially stretched PLLA generates a voltage when the flat plate surface of the piezoelectric film 14 is pressed. At this time, the amount of voltage generated depends on the amount of displacement by which the flat plate surface is displaced in the direction perpendicular to the flat plate surface by the pressing amount.

In the first embodiment, the uniaxial stretching direction of the piezoelectric film 14 (PLLA) is a direction that forms an angle of 45 degrees with respect to the Y direction and the Z direction, as shown by arrows in FIG. The 45 degrees includes an angle including about 45 degrees ± 10 degrees, for example. Thereby, a voltage is generated when the piezoelectric film 14 is pressed.

PLLA generates piezoelectricity by molecular orientation treatment such as stretching, and does not need to be polled like other polymers such as PVDF or piezoelectric ceramics. That is, the piezoelectricity of PLLA that does not belong to ferroelectrics is not expressed by the polarization of ions like ferroelectrics such as PVDF or PZT, but is derived from a helical structure that is a characteristic structure of molecules. is there. For this reason, the pyroelectricity generated in other ferroelectric piezoelectric materials does not occur in PLLA. Since there is no pyroelectricity, the influence of the temperature of the user's finger or frictional heat does not occur, so that the front panel 4 can be formed thin. Further, PVDF or the like shows a change in piezoelectric constant over time, and in some cases, the piezoelectric constant may be significantly reduced, but the piezoelectric constant of PLLA is extremely stable over time. Therefore, it is possible to detect displacement due to pressing with high sensitivity without being affected by the surrounding environment.

Note that the piezoelectric film 14 may be made of a film made of a ferroelectric material in which ions are polarized, such as PVDF or PZT subjected to poling treatment, instead of PLLA.

The first electrode 11, the second electrode 12, and the reference electrode 13 formed on both main surfaces of the piezoelectric film 14 are preferably metal electrodes such as aluminum or copper. By providing the first electrode 11, the second electrode 12, and the reference electrode 13 as described above, the charge generated by the piezoelectric film 14 can be acquired as a voltage, and a pressing amount detection signal having a voltage value corresponding to the pressing amount is output to the outside. Can be output.

Here, the detection method of the voltage and position which generate | occur | produce when the electronic device 1 receives pressing operation is demonstrated. FIG. 6A is a diagram for explaining the relationship between the position where the pressing operation of the first electrode 11 and the second electrode 12 according to the first embodiment is received and the generated voltage. FIG. 6B is a diagram for explaining the relationship between the ratio of the generated voltage in the first electrode 11 and the second electrode 12 and the position where the pressing operation is received.

6 (A) and 6 (B) show voltage measurements on the assumption that a reference electrode 13, a piezoelectric film 14, and a first electrode 11 and a second electrode 12 are laminated on a polycarbonate flat plate (not shown). It is a simulation. The first electrode 11, the second electrode 12, the reference electrode 13, and the piezoelectric film 14 are all fixed at both ends in the Y direction. The flat plate of polycarbonate assumes a shape of 100 × 100 × 1 mm. The first electrode 11 and the second electrode 12 are assumed to be formed so that the width in the Y direction is 90 mm, the maximum width in the Z direction is 5 mm, and the X thickness is 0.5 mm. The center position in the Y direction is shown as 0 mm. The pressing position is -45 mm to 45 mm.

In this configuration, when the piezoelectric film 14 is deformed by a pressing operation, the first electrode 11 and the second electrode 12 arranged side by side in the Y direction simultaneously output a voltage. The voltages output from the first electrode 11 and the second electrode 12 respectively correspond to the area of the electrode at the position where the pressing operation is received, that is, the width in the Z direction. As shown in FIG. 4, the first electrode 11 has the same width at any position along the Y direction. When the first electrode 11 is divided into predetermined sections along the Y direction, the area of each predetermined section is uniform. For this reason, as shown to FIG. 6 (A), the voltage according to this uniform area is output according to the position which receives pressing operation in a Y direction. For example, when the position where the pressing operation is received is 0 mm in the Y direction, the voltage output from the first electrode 11 has a maximum value in the minus direction. When the position for accepting the pressing operation is −45 mm or 45 mm in the Y direction, the piezoelectric film 14 is hardly deformed, and the voltage output from the first electrode 11 has a minimum value in the minus direction. Here, the voltage output from the first electrode 11 is represented as V1. V1 corresponds to the first voltage in the present invention. The first electrode 11 outputs a voltage of a quadratic curve (V1) with the center in the Y direction as a boundary.

On the other hand, the area of the second electrode 12 changes along the Y direction. For this reason, the 2nd electrode 12 outputs the voltage according to the position and area which receive pressing operation in a Y direction. When the piezoelectric film 14 is deformed by the pressing operation, the first electrode 11 and the second electrode 12 are similarly deformed, but the areas of the places where the deformation is received are different. Thereby, the output from each electrode of the first electrode 11 and the second electrode 12 becomes an output ratio according to the area ratio of the first electrode 11 and the second electrode 12 that has been deformed. Here, the voltage output from the second electrode 12 is represented as V2. V2 corresponds to the second voltage in the present invention. The detection unit 18 detects voltages (V1 and V2) output from the piezoelectric element 10.

The calculation unit (not shown) calculates the ratio (μ) of the voltage (V1) output from the first electrode 11 to the voltage (V2) output from the second electrode 12. The ratio (μ) is calculated by the equation μ = V2 / V1. As shown in FIG. 6B, the ratio (μ) decreases linearly as the pressing position moves in the positive direction of the Y direction. For this reason, by storing a relationship in which the pressing position and the ratio (μ) are associated in advance, it is possible to determine which position has been subjected to the pressing operation based on the value of the ratio (μ) obtained from the calculation unit.

It is preferable that the width of the second electrode 12 decreases or increases linearly along the positive direction of the Y direction. The ratio (μ) monotonously decreases or increases as the width of the second electrode 12 monotonously decreases or increases along the Y direction. Thereby, since the relationship between the pressed position and the ratio (μ) is 1: 1, the pressed position can be clearly detected by obtaining the ratio (μ). Therefore, when any of the first pressing part 51, the second pressing part 52, or the third pressing part 53 is subjected to a pressing operation, a ratio (μ) of positions corresponding to each is obtained. Thereby, it is possible to determine which of the first pressing part 51, the second pressing part 52, or the third pressing part 53 has undergone the pressing operation.

Moreover, since the pressing position is detected by the ratio (μ), it is possible to suppress the influence of deformation and the pressing speed. For example, in the 1st press part 51, the 2nd press part 52, or the 3rd press part 53, the case where it is a button formed with the material from which the position of the 2nd press part 52 differs is mentioned. When the second pressing part 52 is made of a material that is hard and hardly distorted, and receives a pressing operation, the distortion of the piezoelectric film 14 at a portion corresponding to the second pressing part 52 is small. At this time, both V1 and V2 become small. Conversely, when the second pressing portion 52 is a button formed of a soft and easily distorted material, both V1 and V2 become large. In order to detect the pressed position, the ratio of V1 and V2 is calculated, so the degree of deformation is canceled out and is not affected by the degree of deformation of the pressed position. Similarly, the degree of deformation is canceled between V1 and V2 depending on the pressing speed and strength of the user. For this reason, the influence by a user's pushing speed and intensity | strength can be suppressed.

FIGS. 7A to 7D and FIGS. 8A to 8D are diagrams for explaining modifications of the first electrode 11 and the second electrode 12 according to the first embodiment. Also in the following modifications 1 to 8, when the pressing position moves along the positive direction of the Y direction as in the first electrode 11 and the second electrode 12 of the first embodiment, the ratio of V1 and V2 (μ ) Will change. Thereby, a press position is detectable.

Also, even when a location slightly away from the electrode is pressed, the pressed position can be detected in the same manner as when the location where the electrode exists is pressed. For example, in the case of FIG. 7A, the pressing position in the Y-axis direction can be detected regardless of where the pressing is applied in the Z-axis direction. That is, the pressing position in the Y-axis direction can be recognized not only in the vicinity of the electrode forming portion but also in a case where a portion slightly away from the electrode is pressed. This will be described in detail in the embodiments described later.

As shown in FIG. 7A, Modification 1 includes a first electrode 21 and a second electrode 22. The first electrode 21 is the same as the first electrode 11 according to the first embodiment. The second electrode 22 has a trapezoidal shape in which the width in the Z direction increases along the plus direction in the Y direction. In the first modification, since the second electrode 22 has a trapezoidal shape, there is a width in the Z direction at the negative end in the Y direction. For this reason, even when the negative end portion in the Y direction is pressed, the output from the second electrode 22 has a certain level or more, so that the pressing position can be detected more accurately at the end portion.

As shown in FIG. 7B, Modification 2 includes a first electrode 23 and a second electrode 24. The first electrode 23 is the same as the first electrode 11 according to the first embodiment. The second electrode 24 has a shape in which the width in the Z direction increases at a predetermined rate for each predetermined section along the positive direction in the Y direction.

As shown in FIG. 7C, the third modification includes a first electrode 25 and a second electrode 26. The first electrode 25 is the same as the first electrode 11 according to the first embodiment. The second electrode 26 is formed in an isosceles triangle and has a shape in which the width in the Z direction increases along the positive direction in the Y direction.

As shown in FIG. 7D, Modification 4 includes a first electrode 27 and a second electrode 28. The piezoelectric element of Modification 4 is attached to a conical casing 71. The first electrode 27 is formed to have the same width in the Z direction. The second electrode 28 is generally triangular and has a shape in which the width in the Z direction changes along the positive direction of the Y direction, which is the circumferential direction.

As shown in FIG. 8A, the modified example 5 includes a first electrode 31 and a second electrode 32. The first electrode 31 has a trapezoidal shape in which the width in the Z direction increases along the plus direction in the Y direction. The second electrode 32 has a trapezoidal shape in which the width in the Z direction increases along the negative direction in the Y direction. In the modified example 5, as shown in FIG. 8A, the first electrode 31 and the second electrode 32 are generally arranged as a whole by arranging the sides whose angles with respect to the other sides are not perpendicular to each other. It is formed in a rectangular shape. For this reason, since a useless area | region does not arise in a Z direction, size reduction of the pushing position detection sensor 100 is attained.

As shown in FIG. 8B, Modification 6 includes a first electrode 33 and two second electrodes 34. The first electrode 33 has a triangular shape in which the width in the Z direction increases along the positive direction in the Y direction. The second electrode 34 has a triangular shape whose width in the Z direction increases along the negative direction of the Y direction. Since two ratios between the voltage output from the first electrode 33 and the voltage output from each second electrode 34 are obtained, the accuracy of detecting the position can be further increased. The first electrode 33 or the second electrode 34 may be plural or singular.

As shown in FIG. 8C, the modified example 7 includes a first electrode 35 and a second electrode 36. The first electrode 35 has a trapezoidal shape in which the width in the Z direction increases along the plus direction in the Y direction. The second electrode 36 is formed in a shape surrounding the first electrode 35. The width of the second electrode 36 increases in the Z direction along the negative direction of the Y direction. Therefore, since the width of the first electrode 35 and the second electrode 36 in the Z direction changes along the Y direction, the pressing position in the Y direction can be detected.

As shown in FIG. 8D, the modified example 8 includes a first electrode 37 and a second electrode 38. The first electrode 37 and the second electrode 38 have a rectangular shape as a whole, but the adjacent sides of the first electrode 37 and the second electrode 38 are formed in a curved shape. Therefore, the voltage output from the first electrode 37 has a relatively small change on the negative side in the Y direction, and the change can be increased toward the positive side in the Y direction. Thus, by increasing the change in the ratio (μ), it can be formed so that even a short movement can be detected with high sensitivity.

FIG. 9A is a view for explaining the first electrode 81 and the second electrode 82 of the push position detection sensor 80 according to the second embodiment. FIG. 9B is a diagram for explaining the relationship between the ratio of the generated voltage in the first electrode 81 and the second electrode 82 according to the second embodiment and the position where the pressing operation is received. In the push position detection sensor 80, only the first electrode 81 and the second electrode 82 are shown.

As shown in FIG. 9A, the push position detection sensor 80 according to the second embodiment includes a first electrode 81 and a second electrode 82. The first electrode 81 includes a plurality of first protrusions 83 that protrude in the Z direction for each predetermined section. The second electrode 82 includes a plurality of second protrusions 84 that protrude in the Z direction for each predetermined section. The plurality of first protrusions 83 have the same area. As for the 2nd protrusion part 84, the area of each 2nd protrusion part 84 reduces along a Y direction. The first protrusions 83 and the second protrusions 84 are alternately arranged along the Y direction.

The push position detection sensor 80 is divided into sections R1, R2, and R3 of equal length in the Y direction as shown in FIG. The area of the first electrode 81 is uniform in each of the sections R1, R2, and R3. On the other hand, since the area of each second protrusion 84 decreases along the Y direction, the area of the second electrode 82 decreases in the order of the sections R1, R2, and R3.

In the push position detection sensor 80, when the user traces the push position detection sensor 80 in the Y direction as indicated by an arrow 801 shown in FIG. 9A, the first electrode 81 and the second electrode according to the position of the user's pressing operation. Each outputs a voltage. Since the first electrode 81 has a uniform area in each of the sections R1, R2, and R3, the same voltage (V1) is output regardless of which of the sections R1, R2, and R3 is subjected to the pressing operation. On the other hand, since the area of the second electrode 82 decreases in the order of the sections R1, R2, and R3, the voltage (V2) that the second electrode 82 outputs in the order of the sections R1, R2, and R3 decreases. Therefore, as the position of the pressing operation of the user moves in the order of the sections R1, R2, and R3, the ratio μ of V1 and V2 obtained as shown in FIG. 9B decreases stepwise. When the user traces the push position detection sensor 80 in the direction opposite to the arrow 801 in the Y direction, the obtained ratio μ of V1 and V2 increases stepwise. Therefore, the push position detection sensor 80 can determine not only the pressed position but also the direction in which the user traces the push position detection sensor 80 (the direction in which the rubbing operation is accepted).

FIG. 10 is a diagram for explaining the relationship between the ratio of the generated voltage in the first electrode 11 and the second electrode 12 according to Examples 1 to 4 and Reference Examples 1 and 2 and the position where the pressing operation is received. Examples 1 to 4 and Reference Examples 1 and 2 will be described below.

For voltage measurement, a laminate of the reference electrode 13, the piezoelectric film 14, and the first electrode 11 and the second electrode 12 on a polycarbonate plate of 100 × 100 × 1 mm was used. The first electrode 11 and the second electrode 12 were formed so that the width in the Y direction was 90 mm, the maximum width in the Z direction was 5 mm, and the X thickness was 0.5 mm. As the piezoelectric film 14, a rectangular film formed by PVDF so that the width in the Y direction was 90 mm, the width in the Z direction was 10 mm, and the X thickness was 0.5 mm was used. As the reference electrode 13, a rectangular electrode formed so that the width in the Y direction was 90 mm and the width in the Z direction was 10 mm was used.

As Example 1, while pressing the center of the first electrode 11 and the second electrode 12 in the Z direction along the Y direction with a force of about 1000 Pa, the pressing position was moved along the Y direction, and the output voltage was measured. . The center position in the Y direction is shown as 0 mm. The pressing position is -45 mm to 45 mm.

As Example 2, the pressing position was measured as 10 mm in the Z direction from the center in the Z direction of the first electrode 11 and the second electrode 12. Similarly, as Example 3, it measured 20 mm from the center of Z direction to Z direction, and as Example 4, it measured as 30 mm from the center of Z direction to Z direction. In Reference Example 1, the pressing position was measured as −10 mm in the Z direction from the center in the Z direction of the first electrode 11 and the second electrode 12, and in Reference Example 2 was measured as −20 mm in the Z direction from the center in the Z direction.

As shown in FIG. 10, in Example 1, the ratio (μ) decreased as the pressing position moved in the positive direction of the Y direction. In Examples 2 to 4, that is, when the pressing position is 10 mm to 30 mm in the Z direction from the center in the Z direction, the ratio (μ) is slightly larger than that in Example 1, but the pressing position is a plus in the Y direction. It decreased like Example 1 as it moved to the direction. In Reference Examples 1 and 2, that is, when the pressing position is −20 mm to −10 mm in the Z direction from the center in the Z direction, the ratio (μ) is slightly smaller than the example, and the pressing position moves in the Y direction. As a result, it was confirmed that it decreased in the vicinity of 0 mm in the Y direction as in the example.

FIG. 11 is a conceptual diagram for explaining the push position detection sensor 101 according to the third embodiment. The pressing position detection sensor 101 and the pressing position detection sensor 102 according to the third embodiment are sensors that detect the pressing position in the detection region 110 on the XY plane. 11, a part of the detection region 110 is omitted. As shown in FIG. 11, the push position detection sensor 101 includes a first electrode 111, a second electrode 112, and a piezoelectric film 114. . The first electrode 111 is the same as the first electrode 11 according to the first embodiment. The second electrode 112 is the same as the second electrode 12 according to the first embodiment. The second electrode 112 has a triangular shape in which the width in the Y direction increases along the positive direction in the X direction.

The push position detection sensor 102 includes a first electrode 115, a second electrode 116, and a piezoelectric film 117. The first electrode 115 is the same as the first electrode 111. The second electrode 116 has a triangular shape in which the width in the Y direction increases along the minus direction in the X direction. The piezoelectric film 117 is the same as the piezoelectric film 114.

In the push position detection sensor 101 and the push position detection sensor 102, the rectangular first electrode 111 and the first electrode 115 are arranged on the side close to the detection region 110. For this reason, the output from the first electrode 111 and the first electrode 115 is relatively uniform and stable even when any position in the X direction of the detection region 110 receives a pressing operation. Further, the triangular second electrode 112 and the second electrode 116 are arranged on the end side of the housing 2 that is far from the detection region 110. For this reason, the second electrode 112 and the second electrode 116 are easily deformed. Therefore, the outputs from the second electrode 112 and the second electrode 116 are easily affected by deformation over the X direction of the detection region 110. Outputs from the second electrode 112 and the second electrode 116 change greatly in the X direction. As a result, the push position detection sensor 101 and the push position detection sensor 102 can accurately detect a change in the X direction.

In the push position detection sensor 101 and the push position detection sensor 102, the directions in which the second electrode 112 and the second electrode 116 are widened are opposite. Thereby, the opposite changes are obtained in the push position detection sensor 101 and the push position detection sensor 102, respectively. For example, the output from the second electrode 112 increases as the pressing position moves toward the plus side in the X direction. Conversely, the output from the second electrode 116 decreases as the pressed position moves toward the plus side in the X direction. Therefore, since the detection position can be detected from both the positive side and the negative side in the X direction, the detection position can be detected more accurately.

When a pressing operation is received in the detection area 110, the piezoelectric film 114 and the piezoelectric film 117 are deformed depending on the position where the pressing operation is received. For example, a case will be described in which the coordinates (x, y = i, j) of lattice points when a detection region 110 is divided into a lattice shape have received a pressing operation. Here, for convenience of explanation, it is assumed that the voltage C1 is output from the first electrode 111 and the voltage D1 is output from the second electrode 112, respectively. In addition, it is assumed that the voltage C2 is output from the first electrode 115 and the voltage D2 is output from the second electrode 116, respectively.

The ratio of the outputs of the push position detection sensor 101 and the push position detection sensor 102 in the case where the coordinate of each grid point has received a press operation is obtained in advance. For example, there are three ratios: p = C1 / D1, q = C2 / D2, and r = D1 / D2. Further, a reference map of three ratios p, q, and r in the coordinates of each lattice point is created. That is, the coordinates of the detection region 110 (x, y = i, j) in _each, p _i, q _ij, previously obtained the _{r ij.} Furthermore, by using four ratios including s = C1 / C2, the pressed position can be detected with higher accuracy. If the accuracy of the pressing position is not required so much, it may be possible to realize only by the ratio of p and q.

When the detection area 110 receives a pressing operation, the push position detection sensor 101 and the push position detection sensor 102 output voltages from the respective electrodes. At this time, the coordinates in the detection region 110 are obtained by the following Equation 1.

Formula 1: f _ij (p, q, r) = f (p−p _ij , q−q _ij , r−r _ij )
In Equation 1, the point where (p−p _ij ) ² + (q−q _ij ) ² + (r−r _ij ) ² becomes the minimum value is calculated. Thereby, the coordinates (x, y = i, j) at which the pressing operation is received in the detection area 110 are obtained. Thus, by assigning a switch for each predetermined coordinate in advance, it becomes possible to identify which coordinate switch has received the pressing operation.

In addition, by expressing p, q, r, and s with an appropriate regression model with x and y as variables, the variables x and y can be obtained from the actually obtained values.

FIG. 12A is a view for explaining the first electrode 41 and the second electrode 42 of the push position detection sensor 120 according to the fourth embodiment. FIG. 12B is a view for explaining the positional relationship between the position to receive the pressing operation and the piezoelectric films 121 to 124 according to the fourth embodiment. FIG. 12C is a diagram for explaining the relationship between the ratio of the generated voltages in the first electrode 41 and the second electrode 42 and the position where the pressing operation is received. In FIG. 12B, only a part of the housing 2 is shown.

As shown in FIG. 12A, the push position detection sensor 120 according to the fourth embodiment includes piezoelectric films 121 to 124, four first electrodes 41, and second electrodes 42 to 45. The piezoelectric films 121 to 124 are arranged in pairs with one of the first electrodes 41 and one of the second electrodes 42 to 45, respectively. The second electrodes 42 to 45 are arranged so as to be aligned with the first electrode 41 in the Y direction.

The wiring 46 is drawn out from the four first electrodes 41. A wiring 47 is drawn out from the second electrodes 42 to 45. Here, since the wiring 46 and the wiring 47 are actually formed in different layers by through holes or the like, they are configured not to contact each other.

Since the four first electrodes 41 and the second electrodes 42 to 45 are formed in the same layer, the push position detection sensor 120 can be formed thinner. Further, since the first electrode 41 and the second electrodes 42 to 45 are present in the same layer, they are similarly deformed by the pressing operation. Thereby, the sensitivity of the push position detection sensor 120 can be further increased. The push position detection sensor 120 may be configured by forming the first electrode 41 and the wiring 46, the second electrodes 42 to 45, and the wiring 47 in advance in different layers and laminating them.

As shown in FIG. 12 (B), button regions B1 to B4 are arranged in the housing 2 at locations corresponding to the piezoelectric films 121 to 124, respectively. For example, the button region B1 includes a piezoelectric film 121, a first electrode 41, and a second electrode 42.

The four first electrodes 41 have the same area in the YZ plane. For this reason, when the piezoelectric films 121 to 124 are similarly deformed by the pressing operation, voltages of the same magnitude are output from the respective piezoelectric films 121 to 124. On the other hand, the second electrodes 42 to 45 have different sizes in the YZ plane. Therefore, when the piezoelectric films 121 to 124 are similarly deformed by the pressing operation, voltages corresponding to the areas of the respective piezoelectric films 121 to 124 are output from the respective piezoelectric films 121 to 124.

As described above, the generated voltages in the second electrodes 42 to 45 differ depending on the pressed positions of the button areas B1 to B4. Therefore, as shown in FIG. 12C, the ratio of the generated voltages in the first electrode 41 and the second electrodes 42 to 45 differs depending on the button regions B1 to B4. Therefore, it is possible to recognize which position in the button areas B1 to B4 has received the pressing operation based on the ratio of the generated voltages in the first electrode 41 and the second electrodes 42 to 45 detected.

FIGS. 13A to 13C are diagrams for explaining modified examples 9 to 11 according to the fourth embodiment. Note that in the description of the modification 9, the description of the same configuration as that of the fourth embodiment is omitted, and only different points will be described. In the description of the modified examples 10 to 11, the description of the same configuration as that of the modified example 9 is omitted, and only different points will be described.

As shown in FIG. 13A, in the modified example 9, the second electrodes 42 to 45 are arranged so as to be aligned in the Z direction with respect to the first electrode 41, respectively. In the button regions B1 to B4, the first electrode 41 and the second electrodes 42 to 45 are equally arranged in the Y direction. For this reason, there is less blur in the Y direction. Therefore, the accuracy of the push position detection sensor 130 can be further increased.

As shown in FIG. 13B, the modified example 10 differs from the modified example 9 in the direction in which the wiring 46 and the wiring 47 are drawn from the first electrode 41 and the second electrodes 42 to 45. Here, the wiring 46 needs to be configured not to contact the wiring 47 and the second electrodes 42 to 45. Thereby, since the length in which the wiring 46 and the wiring 47 are formed becomes short, the push position detection sensor 131 can be easily manufactured, and the push position detection sensor 131 itself can be reduced in size and weight.

As shown in FIG. 13C, the modified example 11 includes a single piezoelectric film 125 instead of the plurality of piezoelectric films 121 to 124 as compared with the modified example 9. Thereby, since the piezoelectric film 125 is comprised only by one sheet, manufacture of the pushing position detection sensor 132 becomes easy. Further, the push position detection sensor 132 itself can be reduced in size and weight.

FIG. 14A is a view for explaining the first electrode 41 and the second electrodes 42 to 45 of the push position detection sensor 140 according to the fifth embodiment. FIG. 14B is a view for explaining the piezoelectric films 121 to 124 according to the fifth embodiment. FIG. 14C is a diagram for explaining the relationship between the generated voltage in the first electrode 41 and the second electrodes 42 to 45 and the position where the pressing operation is received. In FIG. 14B, the first electrode 41 and the second electrodes 42 to 45 are omitted. In the description of the push position detection sensor according to the fifth embodiment, the description of the same configuration as that of the modification 9 is omitted, and only different points will be described. In FIG. 14C, for convenience of explanation, the first electrode, the second electrode, and the piezoelectric film are further illustrated as being doubled in the Y direction.

As shown in FIG. 14A, in the push position detection sensor 140 according to the fifth embodiment, the area of the second electrodes 42 to 45 in the YZ plane decreases in the positive direction of the Y direction. It is. Note that the area of the second electrodes 42 to 45 in the YZ plane may increase in the positive direction of the Y direction.

As shown in FIG. 14B, in the push position detection sensor 140, the piezoelectric films 121 to 124 have different uniaxial stretching directions alternately. That is, the uniaxial stretching direction of the piezoelectric film 121 and the piezoelectric film 123 (arrow 901 shown in FIG. 14B) and the uniaxial stretching direction of the piezoelectric film 122 and the piezoelectric film 124 (arrow 902 shown in FIG. 14B) Approximately 90 degrees. Thereby, the voltage output from the piezoelectric film 121 and the piezoelectric film 123 and the voltage output from the piezoelectric film 122 and the piezoelectric film 124 have opposite polarities.

Piezoelectric films 121 to 124 have different uniaxial stretching directions along the Y-axis direction. For this reason, when the piezoelectric films 121 to 124 are similarly deformed by the pressing operation, the magnitude of the voltage output from the first electrode 41 is increased as the pressing position goes in the positive direction of the Y direction, as shown in FIG. S (E1) repeats substantially the same displacement. In contrast, the magnitude (E2) of the voltage output from the second electrodes 42 to 45 gradually decreases as the pressing position moves in the positive direction of the Y direction.

Therefore, it is possible to detect in which direction in the Y direction the pressing position has moved from the change in the ratio of these voltages (E1 / E2 or E2 / E1). That is, the push position detection sensor 140 can detect the sliding direction when a finger or the like is slid in the pressing operation. Here, since an AC signal is obtained, even when the sensor characteristic drifts due to a temperature change, a stable signal intensity can be obtained by extracting and correcting the change.

15 (A) and 15 (B) are plan views of another example of the electronic apparatus 1 including the push position detection sensor according to the first embodiment. In another example of the electronic device 1, the description of the same configuration as that of the electronic device 1 including the push position detection sensor according to the first embodiment will be omitted, and only different points will be described. Further, the piezoelectric element 10 is transmitted for the sake of explanation and represents its position.

As shown in FIG. 15A, the electronic device 150 is an operation panel of a remote controller. As the electronic device 150, operation panels, such as a washing machine and a rice cooker, are mentioned besides a remote controller.

The electronic device 150 includes a plurality of operation buttons 152, an operation surface 153, and two piezoelectric elements 10. Each of the operation buttons 152 is a section of the operation surface 153 and is provided on the same plane as the operation surface 153. For this reason, the operation surface is flat and can be kept hygienic without dust and the like collecting.

The piezoelectric element 10 is attached to the back surface of the operation surface 153 on the side to be operated. The piezoelectric element 10 is disposed outside the region where the plurality of operation buttons 152 are formed, with the plurality of operation buttons 152 being sandwiched therebetween in the Y-axis direction. Similar to the push position detection sensor according to the third embodiment, when any of the operation buttons 152 accepts a pressing operation, the output from the two piezoelectric elements 10 detects which of the operation buttons 152 accepts the pressing operation. can do.

As shown in FIG. 15 (B), the electronic device 151 differs from the electronic device 150 in the arrangement of the two piezoelectric elements 10. In the electronic device 151, the piezoelectric element 10 is disposed between the plurality of operation buttons 152 so as to be sandwiched between the plurality of operation buttons 152 in the Y-axis direction.

When the electronic device 151 is disposed, the distance between the piezoelectric elements 10 can be reduced compared to the case where the piezoelectric element 10 is disposed at the end of the region where the operation buttons 152 are formed as in the electronic device 150. For example, when the surface area of the operation surface 153 of the electronic device 150 is large, if the operation button 152 near the center is operated, the piezoelectric element 10 is greatly separated from the operation location, so that there is a possibility that the piezoelectric element 10 cannot sufficiently detect deformation. . On the other hand, in the case of the arrangement of the electronic device 151, since the piezoelectric element 10 is arranged between the operation buttons 152, the piezoelectric element 10 can be arranged near the portion to be deformed. Can be improved. In the electronic device 151, the number of piezoelectric elements 10 is not limited to two, and may be three or more. Thereby, detection accuracy can be further improved.

In the electronic device 150, the number of the piezoelectric elements 10 may be increased, and the operation buttons 152 may be arranged between the plurality of operation buttons 152 as in the electronic device 151. Thereby, detection accuracy can be further improved.

FIG. 16A is a diagram for explaining the first electrode 161 and the second electrode 162 of the push position detection sensor 160 according to the sixth embodiment. FIGS. 16B and 16C are diagrams for explaining the relationship between the value calculated based on the generated voltage in the first electrode 161 and the second electrode 162 according to the sixth embodiment and the position where the pressing operation is received. FIG. In the push position detection sensor 160, only the first electrode 161 and the second electrode 162 are shown.

As shown in FIG. 16A, the push position detection sensor 160 according to the sixth embodiment includes a first electrode 161 and a second electrode 162. The first electrode 161 and the second electrode 162 each change in the width in the Z direction along the Y direction. The width of the first electrode 161 in the Z direction increases in the direction of increasing in the Y direction, and the width of the second electrode 162 decreases in the direction of increasing in the Y direction. The first electrode 161 and the second electrode 162 increase or decrease from each other along the Y direction so as to keep the sum of the widths in the Z direction constant. For this reason, the push position detection sensor 160 has a constant sum of voltages generated from the first electrode 161 and the second electrode 162 regardless of which position in the Y direction receives the pressing operation.

When the pressing position detection sensor 160 receives a pressing operation from the user, the first electrode 161 and the second electrode 162 output voltages (V1 and V2) corresponding to the positions at which the pressing operation is received, respectively. The push position detection sensor 160 calculates a value 1 (V1 / (V1 + V2)) and a value 2 (V2 / (V1 + V2)) from the values output from the first electrode 161 and the second electrode 162.

As shown in FIG. 16B, in the push position detection sensor 160, the value 1 increases as the position where the pressing operation is received proceeds in the increasing direction in the Y direction. On the other hand, as shown in FIG. 16C, in the push position detection sensor 160, the value 2 decreases as the position where the pressing operation is received proceeds in the increasing direction in the Y direction. Therefore, it is possible to determine which position has received the pressing operation from the value 1 and the value 2. The position may be determined from either one of the value 1 and the value 2.

Here, the case where the relationship between the position where the pressing operation is received and the obtained value 1 and value 2 in the push position detection sensor 160 is obtained in advance will be described. For example, when the pressing position detection sensor 160 receives a pressing operation from the user at P1 shown in FIG. 16A, C1 is obtained as a value 1 as shown in FIG. At the same time, C2 is obtained as a value 2 as shown in FIG.

From the obtained C1 and C2, the corresponding position where the pressing operation is accepted can be obtained. When the obtained pressing position is the same, the pressing position is obtained with high accuracy. On the other hand, when the obtained pressing positions are different, the positioning accuracy can be increased by averaging. Thereby, the error which the pushing position detection sensor 160 detects can be suppressed. If the pressed position is far from the assumed value, it can be predicted that a problem has occurred in the pressed position detection sensor 160.

In the embodiment, the case 2 has a rectangular parallelepiped shape and the case 71 has a conical shape. However, the shape of the case 2 or the case 71 is not limited thereto. Examples of the shape of the housing 2 include other shapes such as a cylinder, a polygonal column, a sphere, and a polygonal pyramid.

Finally, the description of the present embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

DESCRIPTION OF SYMBOLS 1,150,151 ...

Electronic device

2,71 ... Housing | casing 10 ...

Piezoelectric element

11,21,23,25,27,31,33,35,37,41,81,111,115,161 ...

1st electrode

12 , 22, 24, 26, 28, 32, 34, 36, 38, 42, 43, 44, 45, 82, 112, 116, 162 ... second electrode 13 ...

reference electrodes

14, 114, 117, 121, 122, 123, 124, 125, ... Piezoelectric film 18 ... Detection part 83 ... First protrusion 84 ...

Second protrusion

80, 100, 101, 102, 120, 130, 131, 132, 140, 160 ... Push position detection sensor R1 , R2, R3 ... section Y ... second direction Z ... first direction

Claims

A piezoelectric film deformed by a pressing operation from a user;
A first electrode formed on the first main surface of the piezoelectric film;
A second electrode formed on the first main surface of the piezoelectric film;
A reference electrode formed on the second main surface of the piezoelectric film;
With
The first electrode and the second electrode are arranged side by side in a first direction,
The difference in width between the first electrode and the second electrode in the first direction is a push position detection sensor that is different from each other along a second direction perpendicular to the first direction.
The push position detection sensor according to claim 1, wherein the first electrode has a uniform area along the second direction.
The pressing position detection sensor according to claim 1, wherein the second electrode has an area that increases or decreases uniformly along the second direction.
The first electrode includes a plurality of first protrusions protruding in the first direction for each predetermined section,
The second electrode includes a plurality of second protrusions protruding in the first direction for each predetermined section,
The first protrusions have the same area,
The second projecting portion increases or decreases the area of each second projecting portion along the second direction,
The push position detection sensor according to claim 2, wherein the first protrusions and the second protrusions are alternately arranged along the second direction.
A detector for detecting a position deformed by a pressing operation of the piezoelectric film by calculating a ratio of the first voltage output from the first electrode to a second voltage output from the second electrode; The push position detection sensor according to any one of claims 1 to 4.
An electronic device comprising the push position detection sensor according to any one of claims 1 to 4.