JP2016014668A - Pressure detection device and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure detection device capable of detecting a position and a load inside a piezoelectric sensor.SOLUTION: A pressure detection device 1 includes a piezoelectric layer 11; first electrodes 12, second electrodes 13, a first detection section 21, and a second detection section 22. Each first electrode 12 includes a band pattern electrode constituted by band electrodes 150, 151, 152 arranged in one direction. Each second electrode 13 includes step-in parts 163, step parts 164, and an L shape connection part 165. The step-in parts 163 are arranged between the respective band electrodes 150, 151, 152. The step parts 164 connect the step-in parts 163. The step parts 164 are intersected with the band electrodes 150, 151, 152 by one-to-one correspondence. The L shape connection parts 165 connect the start points of the step-in parts 163 to the end points of the step parts 164.

Description

  The present invention relates to a piezoelectric sensor that generates a piezoelectric signal corresponding to a load, and more particularly to a piezoelectric sensor that can detect a position where a load is applied.

  In order to detect a given load, a piezoelectric sensor using a piezoelectric layer is known. For example, Patent Document 1 discloses a transparent piezoelectric sensor including a transparent pressure-sensitive layer and a pair of transparent conductive layers.

JP 2004-125571 A

  However, the transparent piezoelectric sensor of Patent Document 1 can detect a given load, but cannot detect the position in the transparent piezoelectric sensor.

  In order to achieve the above object, the present invention is configured as follows.

  The pressure detection device of the present invention includes a piezoelectric layer, a first electrode, a second electrode, a first detection unit, and a second detection unit. The first electrode is laminated on the first main surface side of the piezoelectric layer. The first electrode includes a pattern electrode. The pattern electrode includes an L-type reference electrode and an L-type electrode. The L-type reference electrode is an L-shaped electrode in which two sides are combined. The L-type electrode is an L-shaped electrode that is arranged in plural in one direction from the two sides of the L-type reference electrode, and the end side of the L-type electrode is the end of the L-type reference electrode. It is arranged on the extended line of the side.

  Then, the number of the L-type reference electrode and the L-type electrode arranged varies depending on the position in the one direction. The L-type reference electrode and the L-type electrode are connected to the L-type reference electrode detection unit and the L-type electrode of the first electrode. Therefore, when a load is applied to the piezoelectric layer, the number of the L-type reference electrode detection units and the L-type electrode detection units that detect charges differs depending on the position in the one direction where the load is applied. Therefore, by specifying the number of detection units that have detected charges, the position in one direction to which a load is applied can be specified.

  The second electrode is stacked on the second main surface side of the piezoelectric layer. The second electrode includes a plurality of strip-like electrodes that are arranged in a direction perpendicular to the one direction and cover the pattern electrode. The second detection unit includes a strip electrode detection unit that is independently connected to the strip electrode.

  Then, when a load is applied to the piezoelectric layer, the position in the direction perpendicular to the one direction where the load is applied can be specified by specifying the type of the strip-shaped electrode detection unit that detects the electric charge. .

  Therefore, the position to which the load is applied can be specified by combining the position information obtained by the first electrode detection unit and the second electrode detection unit.

The pressure detection device of the present invention includes a piezoelectric layer, a first electrode, two electrodes, a first detection unit, and a second detection unit. The first electrode is laminated on the first main surface side of the piezoelectric layer. The first electrode includes a strip-shaped pattern electrode composed of a plurality of strip-shaped electrodes arranged in one direction.
The second electrode includes a stepping portion, a step portion, and a connecting portion. The stepping portion is disposed between the strip electrodes. The step portion connects the stepped portions. The step portion intersects with the strip electrode in a one-to-one correspondence. The connection part connects the start point of the stepping part and the end point of the step part. In addition, the 1st detection part is provided with the strip | belt-shaped electrode detection part connected with each strip | belt-shaped electrode of a strip | belt-shaped pattern electrode. The second detection unit includes a plurality of strip electrode detection units connected to the plurality of step electrodes.

  Then, the number of overlapping strip electrodes and staircase electrodes varies depending on the position in the one direction. The strip electrode is connected to the strip electrode detector. Therefore, when a load is applied to the piezoelectric layer, the number of strip-shaped electrode detection units that detect charges varies depending on the position in the one direction. Therefore, by specifying the number of detection units that have detected charges, the position in one direction to which a load is applied can be specified.

  The second electrode is stacked on the second main surface side of the piezoelectric layer. The second electrode includes a staircase electrode. The second detection unit includes a staircase electrode detection unit that is independently connected to the staircase electrode.

  Then, when a load is applied to the piezoelectric layer, by specifying the type of the staircase electrode detection unit that detects charges generated from the piezoelectric layer, the position in the direction perpendicular to the one direction where the load is applied can be specified. It is like that.

  Therefore, the position to which the load is applied can be specified by combining the position information obtained by the first electrode detection unit and the second electrode detection unit.

  A reference electrode may be provided between the first electrode and the second electrode.

  Then, the charge generated between the upper electrode and the reference electrode and the charge generated between the lower electrode and the reference electrode can be detected independently.

  The piezoelectric layer may be composed of an active piezoelectric portion and an inactive piezoelectric portion, and a first electrode and a second electrode may be laminated on the active piezoelectric portion.

  Then, the occurrence of the crosstalk phenomenon can be prevented. As a result, the detection accuracy of the position applied to the piezoelectric sensor and the load is improved.

  The upper electrode may contain indium tin oxide or polyethyldioxothiophene.

  Then, since the transparency of the upper electrode is increased, the piezoelectric sensor can be disposed on a display device such as a liquid crystal or an organic EL.

  The lower electrode may contain indium tin oxide or polyethyldioxothiophene.

  Then, since the transparency of the lower electrode is increased, a piezoelectric sensor can be disposed on a display device such as a liquid crystal or an organic EL.

  The piezoelectric layer may be composed of an organic piezoelectric material.

  Then, since the flexibility of the piezoelectric layer is increased, the bending resistance of the piezoelectric sensor is improved. As a result, the piezoelectric sensor can be arranged on an R curved surface.

  The organic piezoelectric material may contain polyvinylidene fluoride or polylactic acid.

  Then, since the transparency of the piezoelectric layer is increased, the piezoelectric sensor can be disposed on a display device such as a liquid crystal or an organic EL.

  The piezoelectric layer may be made of an inorganic material.

  Then, since the piezoelectric constant of the piezoelectric layer is increased, the detection sensitivity for detecting force is improved.

  The electronic device may include a piezoelectric sensor and a touch panel.

  As a result, even when a load is hardly applied to the piezoelectric sensor, the position of the load can be detected.

  The touch panel may be a capacitive touch panel. If it does so, the transparency of the whole pressure detection apparatus will improve.

  In the piezoelectric sensor according to the present invention, position detection can be performed within the piezoelectric sensor.

It is a conceptual diagram of a pressure detection apparatus. FIG. 2 is a cross-sectional view taken along the line A-A ′ of FIG. 1. It is a conceptual diagram of a pressure detection apparatus. It is a conceptual diagram of a pressure detection apparatus. It is a conceptual diagram of a pressure detection apparatus. FIG. 6 is a B-B ′ sectional view of FIG. 5. It is a conceptual diagram of a pressure detection apparatus. It is a conceptual diagram of a pressure detection apparatus. It is sectional drawing of a piezoelectric sensor. It is sectional drawing of the pressure detection apparatus which combined the piezoelectric sensor and the touchscreen.

  Hereinafter, embodiments according to the present invention will be described in more detail with reference to the drawings. It should be noted that the dimensions, materials, shapes, relative positions, etc. of the parts and portions described in the embodiments of the present invention are not intended to limit the scope of the present invention only to those unless otherwise specified. This is just an illustrative example.

1. First Embodiment (1) Overall Structure of Pressure Detection Device The overall structure of a pressure detection device according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic view of a pressure detection device. FIG. 2 is a sectional view of the piezoelectric sensor.

The pressure detection device has a function of detecting the amount and position of a given load.
As shown in FIG. 1, the pressure detection device 1 includes a piezoelectric sensor 10 and a detection unit 20. The piezoelectric sensor 10 is a device that generates an electric charge according to a given load. The detection unit 20 is a device that detects charges generated in the piezoelectric layer 11. Below, the structure of the pressure detection apparatus 1 is demonstrated in detail.

(2) Piezoelectric Sensor As shown in FIG. 2, the piezoelectric sensor 10 includes a piezoelectric layer 11, a first electrode 12, and a second electrode 13. The first electrode 12 is disposed on the first main surface side of the piezoelectric layer 11, and the second electrode 13 is disposed on the second main surface side opposite to the first main surface side of the piezoelectric layer 11. Although not shown, a reference electrode may be provided between the first electrode 12 and the second electrode 13.

As shown in FIG. 3, the first electrode 12 includes a first pattern electrode 120, a second pattern electrode 121, and a third pattern electrode 122. The electrode pattern is arranged in the Y-axis direction. Each of the pattern electrodes includes an L-type reference electrode 123 and an L-type electrode 124.
The L-type reference electrode 123 is disposed outside the L-type electrode 124 and has two sides. Of the two sides, the short side is arranged in the Y-axis direction, and the long side is arranged in the X-axis direction orthogonal to the Y-axis direction.

  A plurality of L-type electrodes 124 are arranged inside the L-type reference electrode 123. The L-type electrode 124 includes a first L-type electrode 125, a second L-type electrode 126, and a third L-type electrode 127.

  The short sides of the first L-type electrode 125 to the third L-type electrode 127 are arranged in the Y-axis direction, and the long sides are arranged in the X-axis direction. Further, the end of the short side of the L-type electrode 124 is disposed on an extension line of the end of the short side of the L-type reference electrode 123, and the end of the long side is the end of the long side of the L-type reference electrode 123. It is arranged on the extension line.

  Note that the first L-type electrode 125 is disposed inside the L-type reference electrode 123. The second L-type electrode 126 is disposed inside the first L-type electrode 125. The third L-type electrode 127 is disposed inside the second L-type electrode 126.

  As shown in FIG. 4, the second electrode 13 includes a plurality of strip electrodes. The strip electrode is composed of a first strip electrode 130, a second strip electrode 131, and a third strip electrode 132 arranged in the Y-axis direction. The strip electrode covers the electrode pattern of the first electrode portion 12 via the piezoelectric layer 11. That is, the first strip electrode 130 covers the first pattern electrode 120, the second strip electrode 131 covers the second pattern electrode 121, and the third strip electrode 132 covers the third pattern electrode 122.

  In the above description, the example in which the first electrode 12 includes the three pattern electrodes from the first pattern electrode 120 to the third pattern electrode 122 has been described. However, the present invention is not limited to this. That is, the first electrode may include n (n = 1, 2, 3,...) Pattern electrodes. The same applies to the L-shaped electrode and the strip electrode.

(3) Electrode The 1st electrode 12 and the 2nd electrode 13 can be comprised with the material which has electroconductivity. Examples of the conductive material include transparent conductive oxides such as indium-tin oxide (ITO), tin-zinc oxide (TZO), and polyethylenedioxythiophene. A conductive polymer such as (Polyethylenedioxythiophene, PEDOT) can be used. In this case, the electrode can be formed by using vapor deposition or screen printing.

  Alternatively, a conductive metal such as copper or silver may be used as the conductive material. In this case, the electrode may be formed by vapor deposition, or may be formed using a metal paste such as a copper paste or a silver paste.

Furthermore, a conductive material in which conductive materials such as carbon nanotubes, metal particles, and metal nanofibers are dispersed may be used as the conductive material.
(4) Piezoelectric layer Examples of the material constituting the piezoelectric layer 11 include inorganic piezoelectric materials and organic piezoelectric materials.

  Examples of the inorganic piezoelectric material include barium titanate, lead titanate, lead zirconate titanate, potassium niobate, lithium niobate, and lithium tantalate.

  Examples of the organic piezoelectric material include a fluoride polymer or a copolymer thereof, and a polymer material having chirality. Examples of the fluoride polymer or copolymer thereof include polyvinylidene fluoride, vinylidene fluoride-tetrafluoroethylene copolymer, and vinylidene fluoride-trifluoroethylene copolymer. Examples of the polymer material having chirality include L-type polylactic acid and R-type polylactic acid.

  When the pressure detection device 1 is arranged on a display device such as a liquid crystal device or an organic EL device, the piezoelectric layer is made of a transparent material so that the display of the display device can be seen, or It is preferable that the thickness be thin enough to transmit light sufficiently.

(5) Detection Unit As shown in FIG. 1, the detection unit 20 includes a first detection unit 21 and a second detection unit 22. As shown in FIG. 3 again, the first detection unit 21 includes an L-type reference electrode detection unit 210, a first L-type electrode detection unit 211, a second L-type electrode detection unit 212, and a third L-type electrode detection unit 213. Become. The L-type reference electrode detection unit 210 is connected to each L-type reference electrode 123. Similarly, the first L-type electrode detector 211 is connected to each first L-type electrode 125, the second L-type electrode detector 212 is connected to each second L-type electrode 126, and the third L-type electrode detector 213 is Are connected to each third L-type electrode 127.

  With the configuration described above, the L-type reference electrode detection unit 210 can detect charges generated in the piezoelectric layer 11 disposed below the L-type reference electrode 123 when the piezoelectric layer 11 is pressed. Regarding the charges generated in the piezoelectric layer 11 disposed below the first L-type electrode 125, the second L-type electrode 126, and the third L-type electrode 127, the first L-type electrode detection unit 211, the second L-type electrode detection unit 212, It can be detected by the third L-type electrode detector 213.

  Again, as shown in FIG. 4, the second detection unit 22 includes a first strip electrode detection unit 220, a second strip electrode detection unit 221, and a third strip electrode detection unit 222. The first strip electrode detector 220 is connected to the first strip electrode 130. Similarly, the second strip electrode detector 221 is connected to the second strip electrode 131, and the third strip electrode detector 222 is connected to the third strip electrode 132.

  When configured as described above, the first strip electrode detection unit 220 can detect the charge generated in the piezoelectric layer 11 disposed below the first strip electrode 130 when the piezoelectric layer 11 is pressed. The charges generated in the piezoelectric layer 11 disposed below the second strip electrode 131 and the third strip electrode 132 can be detected by the second strip electrode detector 221 and the third strip electrode detector 222, respectively.

  As described above, when the pressure detection device 1 is configured, as shown in FIG. 3 again, in the X1 region in the X-axis direction, the L-type reference electrode 123, the first L-type electrode 125, the second L-type electrode 126, A third L-type electrode 127 is disposed. An L-type reference electrode 123, a first L-type electrode 125, and a second L-type electrode 126 are arranged in the X2 region, and an L-type reference electrode 123 and a first L-type electrode 125 are arranged in the X3 region. An L-type reference electrode 123 is disposed in the X4 region. The L-type reference electrode 123 is connected to the L-type reference electrode detection unit 210, the first L-type electrode 125 is connected to the first L-type electrode detection unit 210, and the second L-type electrode 126 is connected to the second L-type electrode detection unit. The third L-type electrode 127 is connected to the second L-type electrode detection unit 222.

  Therefore, when a load is applied to the X1 region, the charge generated by the load is transferred to the L-type reference electrode 123, the first L-type electrode 125, the second L-type electrode 126, and the third L-type electrode 127. The detection is performed by four detection units: a type reference electrode detection unit 210, a first L type electrode detection unit 211, a second L type electrode detection unit 212, and a third L type electrode detection unit 213.

  When a load is applied to the X2 region, the L-type reference electrode detection unit 210 and the first L-type electrode detection unit 211 pass through the L-type reference electrode 123, the first L-type electrode 125, and the second L-type electrode 126. The charge is detected by the three detection units of the second L-type electrode detection unit 212.

  When a load is applied to the X3 region, charges are passed through the L-type reference electrode 123 and the first L-type electrode 125 through the L-type reference electrode detection unit 210 and the first L-type electrode detection unit 211. Is detected.

  When a load is applied to the X4 region, the charge is detected by one detection unit of the L-type reference electrode detection unit 210 via the L-type reference electrode 123.

  That is, with respect to the X-axis direction, the number of detection units that detect charges differs depending on the portion where the load is applied. Using this difference, the position in the X-axis direction at the position where the load is applied can be specified.

  Further, by configuring as described above, as shown in FIG. 4, the first strip electrode 130 is disposed in the Y1 region in the Y-axis direction, the second strip electrode 131 is disposed in the Y2 region, and the Y3 region. The third belt-like electrode 132 is disposed. The first strip electrode 130, the second strip electrode 131, and the third strip electrode 132 are connected to the first strip electrode detection unit 220, the second strip electrode detection unit 221, and the third strip electrode detection unit 222, respectively.

  Therefore, when a load is applied to the Y1 region, the charge generated by the load is detected by the first strip electrode detection unit 220 via the first strip electrode 130. When a load is applied to the Y2 region, it is detected by the second strip electrode detection unit 221 via the second strip electrode 131. When a load is applied to the Y3 region, the load is applied via the third strip electrode 132. , And is detected by the third strip electrode detector 222.

  That is, in the Y-axis direction, the type of detection unit that detects charges differs depending on the place where the load is applied. Using this difference, the position in the Y-axis direction at the position where the load is applied can be specified.

  Finally, by combining the position information in the X-axis direction and the Y-axis direction detected above, it is possible to specify the position where the load is applied.

  In addition, the detection of the load amount is obtained from the total of detected charges. The method of obtaining the load amount from the charge amount can be achieved by programming a conversion method in advance for detection. Accordingly, it is possible to specify the position and amount of load applied to the piezoelectric sensor.

Thus, the first electrode 11 constituting the piezoelectric sensor 10 includes the L-type reference electrode 123 and the L-type electrode 124, and the L-type electrode 124 is spaced from the two sides of the L-type reference electrode 123 inward. And the number of the L-type reference electrode 123 and the L-type electrode 124 to be arranged varies depending on the position in the X-axis direction. ing.
That is, when a load is applied to an arbitrary portion of the piezoelectric sensor 10, the number of the first detection units 21 that detect charges is a unique number depending on the position in the X-axis direction to which the load is applied. By detecting, the position of the applied load in the X-axis direction can be specified.

  The second electrode 12 constituting the piezoelectric sensor 10 includes a plurality of strip electrodes covering the L-type reference electrode 123 and the L-type electrode 124, and the strip electrodes are independently connected to the respective strip electrode detection units. . As a result, the position in the Y-axis direction where the load is applied can be specified by the type of the strip-shaped electrode detection unit that detects charges.

  Therefore, the position where the load is applied can be specified by combining the detection results of the first electrode and the second electrode.

  Further, the detection of the applied load amount obtains the applied load from the total of the detected charges. The method of obtaining the load amount from the charge amount is achieved by programming a conversion method in advance for detection.

  Therefore, by configuring as described above, the pressure detection device of the present application can detect the position and amount of the applied load when the load is applied.

2. Second Embodiment In the second embodiment, the piezoelectric sensor includes a piezoelectric layer, a first electrode, and a second electrode. The first electrode had a pattern electrode, and the pattern electrode was provided with an L-type reference electrode and an L-type electrode. The second electrode was provided with a strip electrode. However, the first electrode may include a strip electrode, and the second electrode may include a staircase electrode. Below, the strip | belt-shaped electrode with which a 1st electrode is provided, and the staircase electrode with which a 2nd electrode is provided are demonstrated.

  FIG. 5 is a plan view of the pressure detection device 1 according to the second embodiment. FIG. 6 is a cross-sectional view taken along the line B-B ′ in FIG. 5.

  As shown in FIG. 5, the pressure detection device 1 includes a piezoelectric sensor 10, a first detection unit 21, and a second detection unit 22. The piezoelectric sensor 10 includes a piezoelectric layer 11, a first electrode 12, and a second electrode 13. The first electrode 12 is disposed on the first main surface side of the piezoelectric layer 11, and the second electrode 13 is disposed on the second main surface side opposite to the first main surface side of the piezoelectric layer 11. The first detection unit 21 includes a first strip electrode detection unit 250, a second strip electrode detection unit 251, and a third strip electrode detection unit 252. The second detector 22 includes a first staircase electrode detector 260, a second staircase electrode detector 261, and a third staircase electrode detector 262.

  As shown in FIG. 7, the first electrode 12 includes a first strip pattern electrode 200, a second strip pattern electrode 201, and a third strip pattern electrode 202 arranged in the Y-axis direction. The strip pattern electrode includes a first strip electrode 150, a second strip electrode 151, and a third strip electrode 152 arranged in the Y-axis direction. The first strip electrode 150 of each strip pattern electrode is connected to the first strip electrode detector 250. The second strip electrode 151 and the third strip electrode 152 of each strip pattern electrode are connected to the second strip electrode detector 251 and the third strip electrode detector 252, respectively.

  As shown in FIG. 8, the second electrode 13 includes stepped step electrodes arranged in the Y-axis direction. The staircase electrode includes a first staircase electrode 160, a second staircase electrode 161, and a third staircase electrode 162. Each step electrode includes a stepped portion 163, a stepped portion 164, and an L-shaped portion 165. The stepping portion 163 is arranged in a direction parallel to the strip electrode in plan view. That is, the stepping portion 163 is located above the first strip electrode 150, between the first strip electrode 150 and the second strip electrode 151, between the second strip electrode 151 and the third strip electrode 152, and the third strip electrode 152. It is arranged below at an interval. The stepped portion 164 is disposed in a direction intersecting with the strip electrode and connects the stepped portions 163. The L-shaped portion 165 has an L-shaped shape that connects the start point of the stepping portion 163 and the end point of the stepped portion 164. The first staircase electrode 160 is independent of the first staircase electrode detector 260, the second strip electrode 161 is independent of the second staircase electrode detector 261, and the third strip electrode 162 is independent of the third staircase electrode detector 262. Connected.

  The strip electrode and the staircase electrode are arranged so that the first strip electrode 150, the second strip electrode 151, and the third strip electrode 152 of the strip electrode intersect the stepped portion 164 of the staircase electrode.

As shown in FIG. 7, when configured as described above, in the X1 region in the X-axis direction, the first strip electrode 150, the second strip electrode 151, and the third strip electrode 152 of each strip pattern electrode are The first step electrode 160, the second step electrode 161, and the third step electrode 162 overlap.
In the X2 region, the second strip electrode 151 and the third strip electrode 152 of each strip pattern electrode overlap the first step electrode 160, the second step electrode 161, and the third step electrode 162.
In the X3 region, the third strip electrode 152 of each strip pattern electrode overlaps the first step electrode 160, the second step electrode 161, and the third step electrode 162.

  Therefore, when a load is applied to the X1 region, the charge generated by the load is transmitted through the first strip electrode 150, the second strip electrode 151, and the third strip electrode 152 of each strip pattern electrode. Detection is performed by the detection unit 250, the second strip electrode detection unit 251, and the third strip electrode detection unit 252.

  When a load is applied to the X2 region, the charge is detected by the second strip electrode detector 251 and the third strip electrode detector 252 via the second strip electrode 151 of each strip pattern electrode and the third strip electrode 152. Is done.

  When a load is applied to the X3 region, the load is detected by the third strip electrode detection unit 252 via the third strip electrode 152 of each strip pattern electrode.

  That is, with respect to the X-axis direction, the number of detection units that detect charges differs depending on the portion where the load is applied. Using this difference, the position in the X-axis direction at the position where the load is applied can be specified.

  Further, as shown in FIG. 8, the first staircase electrode 160 is disposed in the Y1 region in the Y-axis direction, the second staircase electrode 161 is disposed in the Y2 region, and the third staircase electrode 162 is disposed in the Y3 region. Has been.

  Therefore, when a load is applied to the Y1 region, the charge generated by the load is detected by the first staircase electrode detector 260 via the first staircase electrode 160. When a load is applied to the Y2 region, it is detected by the second staircase electrode detector 261 via the second staircase electrode 161. When a load is applied to the Y3 region, the load is applied via the third staircase electrode 162. , Detected by the third staircase electrode detector 262.

  That is, in the Y-axis direction, the type of detection unit that detects charges differs depending on the place where the load is applied. Using this difference, the position in the Y-axis direction at the position where the load is applied can be specified.

  Finally, by combining the position information in the X-axis direction and the Y-axis direction detected above, it is possible to specify the position where the load is applied.

  Thus, the piezoelectric sensor 10 includes the piezoelectric layer 11, the first electrode 12, and the second electrode 13, and the first electrode 12 and the second electrode 13 are connected to the first main surface side of the piezoelectric layer 11 and the first electrode. The first electrode 12 is disposed on the second seed surface side, and includes a band-shaped pattern electrode that is arranged in the Y-axis direction and includes a plurality of band-shaped electrodes (first band-shaped electrode 150, second band-shaped electrode 151, and third band-shaped electrode 152). The second electrode 13 connects the plurality of stepped portions 163 and the stepped portions 163 and intersects with the strip electrodes (the first strip electrode 150, the second strip electrode 151, the third strip electrode 152) in a one-to-one correspondence. A stepped staircase electrode having a plurality of stepped portions 164 and an L-shaped connecting portion 165 connecting the start point of the stepped portion 163 and the end point of the stepped portion 164 (first stepped electrode 160, second stepped electrode 161, By providing three step electrodes 162), X Depending on the position in the direction, strip electrodes (first strip electrode 150, second strip electrode 151, third strip electrode 152) that overlap through the piezoelectric layer 11 and stair electrodes (first stair electrode 160, second stair electrode 161, The number is different from that of the third step electrode 162).

  That is, when a load is applied to a specific portion of the piezoelectric sensor 10, the number of the first detection units 21 that detect charges is a unique number depending on the position in the X-axis direction to which the load is applied. By doing so, the position of the applied load in the X-axis direction can be specified.

  Further, by being configured as described above, a plurality of staircase electrodes are arranged in the Y-axis direction, and the staircase electrodes are connected independently to the respective staircase electrode detectors. As a result, the position in the Y-axis direction where the load is applied can be specified by the type of the strip-shaped electrode detection unit that detects charges.

  Therefore, the position where the load is applied can be specified by combining the detection results of the first electrode and the second electrode.

  Further, the detection of the applied load amount obtains the applied load from the total of the detected charges. The method of obtaining the load amount from the charge amount is achieved by programming a conversion method in advance for detection.

Therefore, by configuring as described above, the pressure detection device of the present application can detect the position and amount of the applied load when the load is applied.
3. Third Embodiment The piezoelectric layer 11 may be patterned so as to have an active portion and an inactive portion.

  FIG. 9 is a cross-sectional view of the piezoelectric sensor according to the third embodiment.

  As shown in FIG. 9, the piezoelectric layer 11 includes an active piezoelectric portion 110 and an inactive piezoelectric portion 111. The active piezoelectric portion 110 is a portion where electric charges are generated when a load is applied to the piezoelectric sensor 10. On the other hand, the inactive piezoelectric portion 111 is a portion where no charge is generated even when a load is applied.

  In the example of FIG. 9, the L-type reference electrode 123 and the L-type electrode 124 (the first L-type electrode 125, the second L-type electrode 126, and the third L-type electrode 127) are disposed on the upper surface of the active piezoelectric portion 110. On the lower surfaces of the active piezoelectric part 110 and the inactive piezoelectric part 111, a first strip electrode 130 is disposed. With this configuration, it is possible to prevent electric charges generated near the L-type reference electrode 123 from leaking and mixing into the L-type electrode 124 (a crosstalk phenomenon can be prevented). As a result, position detection accuracy and load detection accuracy are improved. FIG. 9 shows an example in which the L-type reference electrode 123 and the L-type electrode 124 are directly laminated on the active piezoelectric portion 110, but between the active piezoelectric portion 110 and the L-type reference electrode 123, or An insulating material such as an adhesive or a film may be laminated between the active piezoelectric portion 110 and the L-type electrode 124.

4). Other Embodiments In the above, the example in which the position and amount of the applied load are detected by the piezoelectric sensor 10 has been described. However, as shown in FIG. 10, the position and amount of the applied load may be detected by laminating the touch panel 50 on the piezoelectric sensor 10.
By laminating the touch panel 50 on the piezoelectric sensor 10, even if the applied load is so small that it cannot be detected by the piezoelectric sensor 10 (in the case of feather touch), the load is obtained by laminating the touch panel 50 on the piezoelectric sensor 10. Can be detected. Of the touch panels, it is particularly preferable to use a capacitive touch panel.

1: pressure detection device 10: piezoelectric sensor 11: piezoelectric layer 12: first electrode 13: second electrode 20: detection unit 21: first detection unit 22: second detection unit 50: touch panel 110: active piezoelectric unit 111: not Active piezoelectric portion 120: first pattern electrode 121: second pattern electrode 122: third pattern electrode 123: L-type reference electrode 124: L-type electrode 125: first L-type electrode 126: second L-type electrode 127: third L-type electrode 130: 1st strip electrode 131: 2nd strip electrode 132: 3rd strip electrode 150: 1st strip electrode 151: 2nd strip electrode 152: 3rd strip electrode 160: 1st staircase electrode 161: 2nd staircase electrode 162: Third step electrode 163: Step portion 164: Step portion 165: L-shaped portion 200: First strip-shaped pattern electrode 201: Second strip-shaped pattern electrode 202: Third strip-shaped pattern electrode 210: L-shaped Quasi-electrode detection unit 211: first L-type electrode detection unit 212: second L-type electrode detection unit 213: third L-type electrode detection unit 220: first strip-shaped electrode detection unit 221: second strip-shaped electrode detection unit 222: third strip-shaped electrode Detection unit 250: first strip electrode detection unit 251: second strip electrode detection unit 252: third strip electrode detection unit 260: first stair electrode detection unit 261: second stair electrode detection unit 262: third stair electrode detection unit

Claims (5)

A piezoelectric layer; a first electrode stacked on the first main surface side of the piezoelectric layer; a second electrode stacked on the second main surface side of the piezoelectric layer and overlapping the first electrode via the piezoelectric layer; A pressure detection device comprising a first detection unit connected to the first electrode and a second detection unit connected to the second electrode,
The first electrode includes a strip-shaped pattern electrode composed of a plurality of strip-shaped electrodes arranged in one direction,
The second electrode is
A plurality of stepped portions, a plurality of stepped portions connecting the stepped portions, a plurality of stepped portions intersecting with the plurality of strip-like electrodes in a one-to-one correspondence, and an L-shape connecting a start point of the stepped portion and an end point of the stepped portion With a connection of
The first detection unit includes a strip electrode detection unit connected to each strip electrode of the strip pattern electrode,
A 2nd detection part is a pressure detection apparatus provided with the some strip | belt-shaped electrode detection part each connected with the said some staircase electrode.   The pressure detection device according to claim 1, wherein a reference electrode is provided between the first electrode and the second electrode.   3. The pressure detection according to claim 1, wherein the piezoelectric layer includes an active piezoelectric portion and an inactive piezoelectric portion, and the first electrode and the second electrode are disposed on the active piezoelectric portion. apparatus.   An electronic device comprising the pressure detection device according to claim 1 and a touch panel.   The electronic device according to claim 4, wherein the touch panel is a capacitance type.

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