# US 10,371,569 B2 · Electrostatic capacitance type transducer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,569 B2 - Document ID: US10371569B2 - Status: Granted - Kind: B2 - Application number: 15/519,103 - Filed: 2015-10-01 - Published: 2017-08-03 - Granted: 2019-08-06 - Earliest claimed: 2014-10-17 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Kazutoshi Torashima; Takahiro Akiyama - Web page: https://patentgrep.com/patent/US10371569B2 ## CPC - G01D 5/24: by varying capacitance - B06B 1/0292: {Electrostatic transducers, e.g. electret-type} - G01H 11/06: by electric means - G01N 29/2406: {Electrostatic or capacitive probes, e.g. electret or cMUT-probes} - G01N 29/2418: {using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics (photoacoustic cells G01N21/1702; measuring characteristics of vibrations by using radiation-sensitive means G01H9/00; acousto-optical conversion techniques for short-range imaging G01S15/8965; sound-producing devices using laser bundle G10K15/046)} - H04R 19/00: Electrostatic transducers - 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 - B06B: METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, {e.g.} FOR PERFORMING MECHANICAL WORK IN GENERAL (for particular applications, see the relevant subclasses, e.g. B07B1/40, B23Q17/12, B24B31/06; measurement of mechanical vibrations G01H; in direction finding, locating, distance or velocity measuring G01S; {generating seismic energy G01V1/02}; control of mechanical vibrations in general G05D; sound-producing devices, e.g. bells, sirens, whistles G10K, {e.g. methods or devices for transmitting, conducting, or directing sound in general G10K11/00}; generation of electrical oscillations H03B; electromechanical resonators in general H03H; electromechanical transducers {for communication techniques, e.g. microphones, speakers} H04R) - G01H: MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) ## Abstract An electrostatic capacitance type transducer includes one or more elements 2. The one or more elements each include a plurality of cell groups 14 each including a cell 1 including a first electrode 4 and a second electrode 5 arranged with a gap therebetween, the second electrode being electrically connected to a shared signal extraction electrode 15. In the cell group, each of the cells has an equal wiring length from the shared signal extraction electrode 15. The electrostatic capacitance of the plurality of cell groups, the wiring resistance between two adjacent cell groups, the number of cell groups in the element, and the central frequency of the element satisfy a predetermined relationship to increase transmission efficiency or reception sensitivity. ## Claims ### Claim 1 An electrostatic capacitance type transducer having an operational central frequency fc, comprising: one or more elements each of which includes N cell groups and a signal extraction electrode that is shared among the N cell groups, wherein each of the N cell groups includes P cells, wherein each of the P cells includes a first electrode and a second electrode arranged with a gap therebetween, wherein the second electrode is electrically connected to the signal extraction electrode, wherein, in each of the N cell groups, each of the P cells has an equal wiring length from the signal extraction electrode, and wherein fc≤1/(2×π×N2×ΔRg×ΔCg), where ΔCg is electrostatic capacitance of each of the N cell groups, ΔRg is wiring resistance between two adjacent cell groups in the N cell groups. ### Claim 2 (depends on 1) The electrostatic capacitance type transducer according to claim 1, comprising the elements and the signal extraction electrode, wherein the second electrode is electrically insulated between the elements. ### Claim 3 (depends on 2) The electrostatic capacitance type transducer according to claim 2, wherein the first electrode is electrically connected between the elements. ### Claim 4 (depends on 1) The electrostatic capacitance type transducer according to claim 1, wherein the cell includes a vibration membrane which is supported so as to be able to vibrate, and wherein the second electrode is a part of the vibration membrane which is supported so as to be able to vibrate. ### Claim 5 (depends on 4) The electrostatic capacitance type transducer according to claim 4, wherein the second electrode is an alloy of aluminum and neodymium. ### Claim 6 (depends on 1) The electrostatic capacitance type transducer according to claim 1, wherein the element includes electrical wiring connecting the second electrodes with each other, and wherein the electrical wiring connects the cells of different adjacent cell groups with each other and does not connect the cells of the same cell group. ### Claim 7 (depends on 6) The electrostatic capacitance type transducer according to claim 6, wherein the plurality of cell groups includes a first cell group and a second cell group which are adjacent each other, and wherein the electrical wiring connects one cell in the first cell group to a plurality of cells in the second cell group. ### Claim 8 (depends on 6) The electrostatic capacitance type transducer according to claim 6, wherein the electrical wiring is an alloy of aluminum and neodymium. ### Claim 9 (depends on 1) The electrostatic capacitance type transducer according to claim 1, wherein the first electrode is an alloy of aluminum and neodymium. ### Claim 10 (depends on 1) The electrostatic capacitance type transducer according to claim 1, further comprising bypass wiring that connects the signal extraction electrode to the second electrode in each of the N cell groups, and wherein a plane to which the bypass wiring is projected does not overlap the first electrode. ### Claim 11 An electrostatic capacitance type transducer having an operational central frequency fc, comprising P cells, wherein each of the P cells includes a first electrode and a second electrode arranged with a gap therebetween, wherein the second electrode is electrically connected to a signal extraction electrode that is shared among the P cells, wherein the P cells have different wiring lengths from the signal extraction electrode, and wherein fc≤1/(2×π×P2×ΔRs×ΔCs) is satisfied, where ΔCs is electrostatic capacitance of each of the P cells, ΔRs is wiring resistance between two adjacent cells in the P cells. ### Claim 12 (depends on 1) An information acquisition apparatus comprising: an electrostatic capacitance type transducer configured to receive an acoustic wave from an object and convert the acoustic wave into an electrical signal; and an acquisition unit configured to acquire information about the object by use of the electrical signal, wherein the electrostatic capacitance type transducer is the electrostatic capacitance type transducer according to claim 1. ### Claim 13 (depends on 12) The information acquisition apparatus according to claim 12, wherein the electrostatic capacitance type transducer transmits an acoustic wave to the object and receives the acoustic wave reflected by the object. ### Claim 14 (depends on 12) The information acquisition apparatus according to claim 12, wherein the electrostatic capacitance type transducer receives an acoustic wave generated by irradiation of the object with light. ### Claim 15 (depends on 14) The information acquisition apparatus according to claim 14, further comprising a light source configured to irradiate the object with light. ### Claim 16 An electrostatic capacitance type transducer having an operational central frequency, comprising: one or more elements each of which includes N cell groups and a signal extraction electrode that is shared among the N cell groups, wherein each of the N cell groups includes P cells, wherein each of the P cells includes a first electrode and a second electrode arranged with a gap therebetween, wherein the second electrode is electrically connected to the signal extraction electrode, wherein N and P are positive integers, wherein, in each of the N cell groups, each of the P cells has an equal wiring length from the signal extraction electrode, and wherein the operational central frequency is less than or equal to an expression scaled by N. ### Claim 17 An electrostatic capacitance type transducer having an operational central frequency, comprising P cells, wherein each of the P cells includes a first electrode and a second electrode arranged with a gap therebetween, wherein P is a positive integer, wherein the second electrode is electrically connected to a signal extraction electrode, wherein the P cells have different wiring lengths from the signal extraction electrode, and wherein the operational central frequency is less than or equal to an expression scaled by P.