# US 9,519,378 B2 · Pressure detector and touch panel provided with pressure detector

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,519,378 B2
- Document ID: US9519378B2
- Status: Granted
- Kind: B2
- Application number: 15/104,679
- Filed: 2014-03-12
- Published: 2016-11-03
- Granted: 2016-12-13
- Earliest claimed: 2013-12-18
- Assignees: Nissha Printing Co., Ltd.
- Applicants: Nissha Printing Co., Ltd.
- Inventors: Yuji Watazu; Keisuke Ozaki; Eiji Kakutani; Junichi Shibata
- Web page: https://patentgrep.com/patent/US9519378B2

## CPC

- G06F 3/0445: {using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer}
- G01L 1/16: using properties of piezoelectric devices
- G06F 3/04144: {using an array of force sensing means (position sensing using the local deformation of sensor cells G06F3/0447)}
- G06F 3/047: using sets of wires, e.g. crossed wires
- G06F 2203/04105: Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
- G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N)
- G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G)

## Abstract

[Object] To provide a pressure detector capable of accurately detecting a pressing force. [Solution] A pressure detector according to the present invention includes a first piezoelectric sheet 3a, a second piezoelectric sheet 3b located so as to be close to or in contact with the first piezoelectric sheet 3a, and a detection electrode 4 that sandwiches the first piezoelectric sheet 3a and the second piezoelectric sheet 3b. The first piezoelectric sheet 3a and the second piezoelectric sheet 3b are composed of materials having identical characteristics and have a thickness of 5 μm to 50 μm. Potential differences respectively generated between surfaces on a support substrate 1 side and surfaces opposite to the support substrate 1 of the first piezoelectric sheet 3a and the second piezoelectric sheet 3b when the first piezoelectric sheet 3a and the second piezoelectric sheet 3b are pulled in an in-plane direction have a relationship expressed by expression 1: V1/V2<0. In expression 1, V1 and V2 represent potential differences respectively generated between the surfaces on the support substrate 1 side and the surfaces opposite to the support substrate 1 of the first piezoelectric sheet 3a and the second piezoelectric sheet 3b.

## Claims

### Claim 1

A touch panel that measures a pressing force of a press applied to an input surface, comprising:
a plurality of upper electrodes located at intervals in one direction;
a plurality of lower electrodes that are located at intervals in a direction crossing the upper electrodes, on a side opposite to an input surface side of the upper electrodes, and that detect a press position between the upper electrodes and the lower electrodes;
a piezoelectric sheet including a first piezoelectric sheet located on a surface opposite to the input surface side of the lower electrodes and a second piezoelectric sheet located on a surface opposite to the input surface side of the first piezoelectric sheet so as to be close to or in contact with the first piezoelectric sheet;
first detection electrodes located in spaces between the lower electrodes in a cross-sectional view of the touch panel; and
a second detection electrode that is located on a surface opposite to the input surface side of the second piezoelectric sheet and that detects a potential difference generated in the piezoelectric sheet in cooperation with the first detection electrodes when the press is applied, wherein
the first piezoelectric sheet and the second piezoelectric sheet are composed of materials having identical characteristics and have a thickness of 5 μm to 50 μm,
potential differences respectively generated between surfaces on the input surface side and surfaces opposite to the input surface of the first piezoelectric sheet and the second piezoelectric sheet when the first piezoelectric sheet and the second piezoelectric sheet are pulled in an in-plane direction have a relationship expressed by expression 3: V1/V2<0, and
in expression 3,
V1 represents V1a−V1b,
V2 represents V2a−V2b,
V1a represents a potential at the surface on the input surface side of the first piezoelectric sheet,
V1b represents a potential at the surface opposite to the input surface side of the first piezoelectric sheet,
V2a represents a potential at the surface on the input surface side of the second piezoelectric sheet, and
V2b represents a potential at the surface opposite to the input surface side of the second piezoelectric sheet.

### Claim 2 (depends on 1)

The touch panel according to claim 1, wherein the lower electrodes also function as the first detection electrodes.

### Claim 3

A touch panel that measures a pressing force of a press applied to an input surface, comprising:
a plurality of upper electrodes located at intervals in one direction;
a plurality of lower electrodes that are located at intervals in a direction crossing the upper electrodes, on a side opposite to an input surface side of the upper electrodes, and that detect a press position between the upper electrodes and the lower electrodes;
a piezoelectric sheet including a first piezoelectric sheet located on a surface opposite to the input surface side of the upper electrodes and a second piezoelectric sheet located on a surface opposite to the input surface side of the first piezoelectric sheet so as to be close to or in contact with the first piezoelectric sheet, the first piezoelectric sheet and the second piezoelectric sheet being located between the upper electrodes and the lower electrodes;
first detection electrodes located in spaces between the upper electrodes in a cross-sectional view of the touch panel; and
second detection electrodes that are located in spaces between the lower electrodes in a cross-sectional view of the touch panel and that detect a potential difference generated in the piezoelectric sheet in cooperation with the first detection electrodes when the press is applied, wherein
the first piezoelectric sheet and the second piezoelectric sheet are composed of materials having identical characteristics and have a thickness of 5 μm to 50 μm,
potential differences respectively generated between surfaces on the input surface side and surfaces opposite to the input surface of the first piezoelectric sheet and the second piezoelectric sheet when the first piezoelectric sheet and the second piezoelectric sheet are pulled in an in-plane direction have a relationship expressed by expression 4: V1/V2<0, and
in expression 4,
V1 represents V1a−V1b,
V2 represents V2a−V2b,
V1a represents a potential at the surface on the input surface side of the first piezoelectric sheet,
V1b represents a potential at the surface opposite to the input surface side of the first piezoelectric sheet,
V2a represents a potential at the surface on the input surface side of the second piezoelectric sheet, and
V2b represents a potential at the surface opposite to the input surface side of the second piezoelectric sheet.

### Claim 4 (depends on 3)

The touch panel according to claim 3, wherein the upper electrodes also function as the first detection electrodes.

### Claim 5 (depends on 3)

The touch panel according to claim 3, wherein the lower electrodes also function as the second detection electrodes.