# US 10,120,519 B2 · Electrostatic detection sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,120,519 B2 - Document ID: US10120519B2 - Status: Granted - Kind: B2 - Application number: 15/533,376 - Filed: 2016-01-12 - Published: 2018-08-23 - Granted: 2018-11-06 - Earliest claimed: 2015-02-18 - Assignees: Panasonic Intellectual Property Management Co., Ltd. - Applicants: Panasonic Intellectual Property Management Co., Ltd. - Inventors: Takateru Sawada; Takuma Besshi; Erika Sawada - Web page: https://patentgrep.com/patent/US10120519B2 ## CPC - G06F 3/044: by capacitive means - G01D 5/24: by varying capacitance - G06F 3/041: Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means - H01H 36/00: Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding - H03K 17/955: using a capacitive detector - H03K 17/962: {Capacitive touch switches} - H03K 2017/9613: {using two electrodes per touch switch} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) ## Abstract A sensor body of an electrostatic detection sensor includes a first electrode and a second electrode surrounding the first electrode. A controller is configured to obtain a first sensed intensity of the sensor body while where the first electrode is connected to the second electrode. The controller is configured to obtain a second sensed intensity of the first electrode while the second electrode is grounded. The controller is configured to obtain a third sensed intensity of the second electrode while the first electrode is grounded. The controller is configured to determine whether an object approaches the sensor body or not based on first to third calculation values obtained by calculating the respective changes of the first to third sensed intensities with respect to time. ## Claims ### Claim 1 An electrostatic detection sensor comprising: a sensor body including a first electrode, and a second electrode surrounding the first electrode while being spaced from the first electrode; and a controller connected to the first electrode and the second electrode, wherein the controller is configured to: obtain a first sensed intensity corresponding to a capacitance of the sensor body while the first electrode is connected to the second electrode; obtain a second sensed intensity corresponding to a capacitance of the first electrode by applying a first driving voltage to the first electrode while the second electrode is grounded to a ground potential; obtain a third sensed intensity corresponding to a capacitance of the second electrode by applying a second driving voltage to the second electrode while the first electrode is grounded to the ground potential; and determine whether an object approaches the sensor body or not based on a first calculation value corresponding to a change of the first sensed intensity with respect to time, a second calculation value corresponding to a change of the second sensed intensity with respect to time, and a third calculation value corresponding to a change of the third sensed intensity with respect to time. ### Claim 2 (depends on 1) The electrostatic detection sensor according to claim 1, wherein the first calculation value is a difference between a value of the first sensed intensity at a first time point and a value of the first sensed intensity at a second time point. ### Claim 3 (depends on 1) The electrostatic detection sensor according to claim 1, wherein the second calculation value is a difference between a value of the second sensed intensity at a first time point and a value of the second sensed intensity at a second time point. ### Claim 4 (depends on 1) The electrostatic detection sensor according to claim 1, wherein the third calculation value is a difference between a value of the third sensed intensity at a first time point and a value of the third sensed intensity at a second time point. ### Claim 5 (depends on 1) The electrostatic detection sensor according to claim 1, wherein the controller is configured to determine whether the object approaches the sensor body by comparing the first calculation value with a predetermined first threshold. ### Claim 6 (depends on 5) The electrostatic detection sensor according to claim 5, wherein the controller is configured to: obtain a fourth calculation value from the second calculation value and a predetermined second threshold; obtain a fifth calculation value from the third calculation value and a predetermined third threshold; and determine that the object approaches the sensor body when the first calculation value is larger than the fourth calculation value and larger than the fifth calculation value. ### Claim 7 (depends on 6) The electrostatic detection sensor according to claim 6, wherein the controller is configured to: obtain the fourth calculation value by multiplying the second calculation value by the predetermined second threshold; and obtain the fifth calculation value by multiplying the third calculation value by the predetermined third threshold. ### Claim 8 (depends on 5) The electrostatic detection sensor according to claim 5, wherein the controller is configured to: obtain a fourth calculation value from the first calculation value and the second calculation value; obtain a fifth calculation value from the first calculation value and the third calculation value; and determine that the object approaches the sensor body when the fourth calculation value is larger than a predetermined second threshold and the fifth calculation value is larger than a predetermined third threshold. ### Claim 9 (depends on 8) The electrostatic detection sensor according to claim 8, wherein the controller is configured to: obtain the fourth calculation value by dividing the first calculation value by the second calculation value; and obtain the fifth calculation value by dividing the first calculation value by the third calculation value. ### Claim 10 (depends on 5) The electrostatic detection sensor according to claim 5, wherein the controller is configured to: obtain a fourth calculation value from the first calculation value and the second calculation value; obtain a fifth calculation value from the first calculation value and the third calculation value; and determine that the object approaches the sensor body when the fourth calculation value is smaller than a predetermined second threshold and the fifth calculation value is smaller than a predetermined third threshold. ### Claim 11 (depends on 10) The electrostatic detection sensor according to claim 10, wherein the controller is configured to: obtain the fourth calculation value by dividing the second calculation value by the first calculation value; and obtain the fifth calculation value by dividing the third calculation value by the first calculation value. ### Claim 12 (depends on 5) The electrostatic detection sensor according to claim 5, wherein the controller is configured to: obtain a fourth calculation value from the first calculation value and the second calculation value; obtain a fifth calculation value from the first calculation value and the third calculation value; and determine that the object approaches the sensor body when the fourth calculation value is smaller than a predetermined second threshold and the fifth calculation value is larger than a predetermined third threshold. ### Claim 13 (depends on 12) The electrostatic detection sensor according to claim 12, wherein the controller is configured to: obtain the fourth calculation value by dividing the second calculation value by the first calculation value; and obtain the fifth calculation value by dividing the first calculation value by the third calculation value. ### Claim 14 (depends on 5) The electrostatic detection sensor according to claim 5, wherein the controller is configured to: obtain a fourth calculation value from the first calculation value and the second calculation value; obtain a fifth calculation value from the first calculation value and the third calculation value; and determine that the object approaches the sensor body when the fourth calculation value is larger than a predetermined second threshold and the fifth calculation value is smaller than a predetermined third threshold. ### Claim 15 (depends on 14) The electrostatic detection sensor according to claim 14, wherein the controller is configured to: obtain the fourth calculation value by dividing the first calculation value by the second calculation value; and obtain the fifth calculation value by dividing the third calculation value by the first calculation value. ### Claim 16 (depends on 1) The electrostatic detection sensor according to claim 1, wherein the object is a finger.