# US 11,998,389 B2 · Focused rotational IVUS transducer using single crystal composite material > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,998,389 B2 - Document ID: US11998389B2 - Status: Granted - Kind: B2 - Application number: 17/498,793 - Filed: 2021-10-12 - Published: 2022-01-27 - Granted: 2024-06-04 - Earliest claimed: 2012-12-21 - Assignees: Philips Image Guided Therapy Corporation - Applicants: Philips Image Guided Therapy Corporation - Inventors: Paul Douglas Corl - Web page: https://patentgrep.com/patent/US11998389B2 ## CPC - A61B 8/4483: {characterised by features of the ultrasound transducer} - A61B 6/461: {Displaying means of special interest} - A61B 8/0891: {for diagnosis of blood vessels} - A61B 8/12: in body cavities or body tracts, e.g. by using catheters - A61B 8/14: Echotomography - A61B 8/445: {Details of catheter construction} - B06B 1/0622: {on one surface} - B06B 1/067: {which is used as, or combined with, an impedance matching layer} - H10N 30/092: Forming composite materials - H10N 30/852: {Composite materials, e.g. having 1-3 or 2-2 type connectivity} - B06B 2201/76: Medical, dental - Y10T 29/49005: Acoustic transducer - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - 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) - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract An ultrasound transducer for use in intravascular ultrasound (IVUS) imaging systems including a single crystal composite (SCC) layer is provided. The transducer has a front electrode on a side of the SCC layer; and a back electrode on the opposite side of the SCC layer. The SCC layer may have a bowl shape including pillars made of a single crystal piezoelectric material embedded in a polymer matrix. Also provided is an ultrasound transducer as above, with the back electrode split into two electrodes electrically isolated from one another. A method of forming an ultrasound transducer as above is also provided. An IVUS imaging system is provided, including an ultrasound emitter and receiver rotationally disposed within an elongate member; an actuator; and a control system controlling emission of pulses and receiving ultrasound echo data associated with the pulses. The ultrasound emitter and receiver include an ultrasound transducer as above. ## Claims ### Claim 1 An IVUS imaging system, comprising: an ultrasound emitter and receiver rotationally disposed within an elongate member; an actuator coupled to the ultrasound emitter and receiver, the actuator moving the ultrasound emitter and receiver through at least a portion of an arc; and a voltage source configured to output a first potential and a second potential; a control system configured to control emitting of a sequence of pulses and receiving of ultrasound echo data associated with the sequence of pulses by the ultrasound emitter and receiver, the control system processing the ultrasound echo data to generate a cross-sectional image of a vessel, wherein the ultrasound emitter and receiver comprises a single ultrasound transducer, the single ultrasound transducer comprising: an electrically floating front electrode; and a back electrode divided into two equal electrode halves, the back electrode comprising a first electrode half connected to the first potential and a second electrode half connected to the second potential such that the front electrode comprises a third potential, via capacitive coupling, that is between the first potential and the second potential. ### Claim 2 (depends on 1) The IVUS imaging system of claim 1, wherein the single ultrasound transducer further comprises a matching layer based on a center frequency of a pulse transmitted by the single ultrasound transducer. ### Claim 3 (depends on 1) The IVUS imaging system of claim 1, wherein the single ultrasound transducer further comprises a matching layer formed as a continuous layer formed over the front electrode. ### Claim 4 (depends on 1) The IVUS imaging system of claim 1, wherein the first and second electrode halves comprise curved outer edges and straight inner edges, and the front electrode comprises a curved outer edge. ### Claim 5 (depends on 1) The IVUS imaging system of claim 1, wherein the single ultrasound transducer is arranged within the elongate member such that the sequence of pulses propagate at an oblique angle with respect to a longitudinal axis of the elongate member. ### Claim 6 (depends on 1) The IVUS imaging system of claim 1, wherein the voltage source is configured to output the first potential comprising a first signal having a first polarity and a first magnitude, and the second potential comprising a second signal having a second polarity and a second magnitude, wherein the first polarity is opposite to the second polarity and the first magnitude is equal to the second magnitude, and wherein the first electrode half is electrically isolated from the second electrode half. ### Claim 7 (depends on 6) The IVUS imaging system of claim 6, wherein the first electrode half is coupled to a first electrical cable carrying the first signal, the second electrode half is coupled to a second electrical cable carrying the second signal, and the front electrode is without a direct external electrical connection. ### Claim 8 (depends on 7) The IVUS imaging system of claim 7, further comprising intermediate conductive members coupling the first electrical cable to the first electrode half and the second electrical cable to the second electrode half. ### Claim 9 (depends on 1) The IVUS imaging system of claim 1, wherein the single ultrasound transducer comprises a piezoelectric material between the front electrode and the back electrode. ### Claim 10 (depends on 9) The IVUS imaging system of claim 9, wherein the piezoelectric material comprises single crystal composite (SCC) material. ### Claim 11 (depends on 10) The IVUS imaging system of claim 10, wherein the SCC material comprises: a first SCC half between the front electrode and the first electrode half; and a second SCC half between the front electrode and the second electrode half. ### Claim 12 (depends on 11) The IVUS imaging system of claim 11, wherein a polarization of the first SCC is in a first direction and the second SCC is in a second direction.