# US 2017/0284972 A1 · Total focusing method adaptively corrected by using plane wave > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0284972 A1 - Document ID: US20170284972A1 - Status: Published application - Kind: A1 - Application number: 15/472,603 - Filed: 2017-03-29 - Published: 2017-10-05 - Earliest claimed: 2016-03-31 - Assignees: Olympus Scientific Solutions Americas Inc. - Inventors: Benoit Lepage; Guillaume Painchaud-April; Jason Habermehl - Web page: https://patentgrep.com/patent/US20170284972A1 ## CPC - G01N 29/069: {Defect imaging, localisation and sizing using, e.g. time of flight diffraction [TOFD], synthetic aperture focusing technique [SAFT], Amplituden-Laufzeit-Ortskurven [ALOK] technique} - G01N 29/043: {in the interior, e.g. by shear waves} - G01N 29/0645: {Display representation or displayed parameters, e.g. A-, B- or C-Scan} - G01N 29/262: {by electronic orientation or focusing, e.g. with phased arrays (phased arrays per se G10K11/34)} - G01N 29/30: Arrangements for calibrating or comparing, e.g. with standard objects - G01N 2291/267: Welds - 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) ## Abstract Disclosed is a phased array ultrasound total focusing method in which the ultrasound energy is transmitted as plane waves and the response signals are processed as plane waves. The processing is adaptively corrected to account for geometric variations in the probes and the part being inspected. Methods are disclosed for measuring the geometric variations of the probes and the part. ## Claims ### Claim 1 A phased array ultrasound (PAUT) imaging system comprising: at least one PAUT probe configured to be coupled with and to test a test object, each one of the at least one probe having an array of ultrasound transducers for transmitting ultrasound energy and receiving response energy; a plane wave generating unit configured to transmit a series of electronic pulses to the at least one probe, the series of electronic pulses configured to cause emission of a number N of transmitted plane waves from the array of ultrasound transducers; a plane wave receiving unit configured to receive response signals responsive to possible flaws in the test object, wherein the response signals from each of the transmitted plane waves are received as a number M of received plane waves, and wherein the response signals from corresponding transmitted plane waves and received plane waves are combined in a plane wave full matrix capture (FMC) matrix, which has a matrix dimension (N×M); and, a plane wave processing module configured to process the plane wave FMC matrix and to produce an image of the flaws in an imaging volume within the test object. ### Claim 2 (depends on 1) The phased array ultrasound imaging system of claim 1 wherein an nth transmitted wave of the N transmitted plane waves has an inclination angle βn and an mth received wave of the M received plane waves has an inclination angle βm, wherein n=1 to N and m=1 to M. ### Claim 3 (depends on 1) The phased array ultrasound imaging system of claim 1 wherein the plane wave processing module further comprises a calibration module for performing a calibration of the plane wave FMC matrix to produce a calibrated plane wave FMC matrix in which an amplitude of the response signals from any selected flaw is substantially the same for any location of the selected flaw within the imaging volume. ### Claim 4 (depends on 3) The phased array ultrasound imaging system of claim 3 wherein the calibration is based on analytic calculations of plane wave transmission and reflection coefficients. ### Claim 5 (depends on 3) The phased array ultrasound imaging system of claim 3 wherein the plane wave processing module further comprises a geometry module configured to determine geometric parameters of the test object and the at least one probe, the geometric parameters comprising at least one thickness measurement of the test object, a location of the at least one probe and an orientation angle of the at least one probe. ### Claim 6 (depends on 5) The phased array ultrasound imaging system of claim 5 wherein the at least one probe is mechanically moved in a scan direction on a surface of the test object thereby having a sequence of probe scan positions, wherein the imaging volume is substantially in a plane perpendicular to the scan direction, a voxel within the imaging volume has coordinates (x,y) and the imaging volume comprises a multiplicity of adjacent voxels. ### Claim 7 (depends on 6) The phased array ultrasound imaging system of claim 6 wherein the plane wave processing module further comprises an adaptive beam forming module receiving input from the calibration module and the geometry module, and producing a plane wave total focusing method (TFM) matrix, TFM(x,y), in which a summation is made of the response signals in the plane wave FMC matrix for each of the multiplicity of voxels. ### Claim 8 (depends on 7) The phased array ultrasound imaging system of claim 7 wherein the summation includes a response signal time delay for the each of the multiplicity of voxels, wherein the time delay is equal to a sum of a transmit time of flight and a receive time of flight, and wherein the transmit time of flight is the time for the transmitted plane wave to reach the voxel and the receive time of flight is the time for the received plane wave to return from the voxel. ### Claim 9 (depends on 7) The phased array ultrasound imaging system of claim 7 wherein the plane wave processing module further comprises an imaging module for forming an image of the flaws in the imaging volume, the imaging module receiving input from the plane wave TFM matrix. ### Claim 10 (depends on 9) The phased array ultrasound imaging system of claim 9 wherein the image is an adaptive image which is corrected in response to a change of at least one of the geometric parameters. ### Claim 11 (depends on 10) The phased array ultrasound imaging system of claim 10 wherein the adaptive image corresponding to each one of the sequence of the probe scan positions is derived using equations in which the coordinates (x,y) are the only variables for each one of the sequence of the probe scan positions. ### Claim 12 An ultrasonic imaging method for imaging flaws in a test object comprising the steps of: placing at least one phased array ultrasound (PAUT) probe in contact with the test object, each one of the at least one probe having an array of ultrasound transducers for transmitting ultrasound energy and receiving response energy; transmitting a series of electronic pulses to the at least one probe, the series of electronic pulses configured to cause emission of transmitted plane waves from the array of ultrasound transducers; receiving response signals responsive to possible flaws in the test object, wherein the response signals from each of the transmitted plane waves are received as received plane waves, and wherein the response signals from corresponding transmitted plane waves and received plane waves are combined in a plane wave full matrix capture (FMC) matrix; and processing the plane wave FMC matrix to produce an image of the flaws in an imaging volume within the test object. ### Claim 13 (depends on 12) The ultrasonic imaging method of claim 12 further comprising a step of calibrating the plane wave FMC matrix to produce a calibrated plane wave FMC matrix, in which an amplitude of the response signal from any selected flaw is substantially the same for any location of the selected flaw within the imaging volume. ### Claim 14 (depends on 13) The ultrasonic imaging method of claim 13 further comprising a step of producing a calibrated plane wave total focusing method (TFM) matrix, in which a summation is made of the response signals in the plane wave FMC matrix. ### Claim 15 (depends on 14) The ultrasonic imaging method of claim 14 wherein the summation includes a response signal time delay for each of the response signals. ### Claim 16 (depends on 15) The ultrasonic imaging method of claim 15 further comprising a step of using data from the calibrated plane wave TFM matrix to form an image of the flaws in the imaging volume. ### Claim 17 (depends on 16) The ultrasonic imaging method of claim 16 further comprising a step of determining geometric parameters of the test object and the at least one probe, the geometric parameters comprising at least one thickness measurement of the test object, a location of the at least one probe and an orientation angle of the at least one probe. ### Claim 18 (depends on 17) The ultrasonic imaging method of claim 17, wherein the image is an adaptive image which is corrected in response to a change of at least one of the geometric parameters. ### Claim 19 (depends on 18) The ultrasonic imaging method of claim 18 further comprising a step of mechanically moving the at least one probe in a scan direction on a surface of the test object, thereby having a sequence of probe scan positions, wherein the imaging volume is substantially in a plane perpendicular to the scan direction, a voxel within the imaging volume has coordinates (x,y), and wherein the adaptive image corresponding to each one of the sequence of probe scan positions is derived using equations in which the coordinates (x,y) are the only variables for each one of the sequence of probe scan positions. ### Claim 20 A phased array ultrasound (PAUT) imaging system comprising: at least one PAUT array probe configured to be coupled with and to test a test object, each one of the at least one probe having an array of ultrasound transducers, the array comprising P transmitters for transmitting ultrasound energy and Q receivers for receiving response energy; a plane wave forming module configured to transmit electronic pulses to the at least one probe, to receive response signals responsive to possible flaws in the test object and to form a plane wave full matrix capture (FMC) matrix, the plane wave FMC matrix being a N×M matrix of N transmitted plane waves and M received plane waves; and, a plane wave processing module configured to process the plane wave FMC matrix and to produce an image of the flaws in the test object. ### Claim 21 (depends on 20) The phased array ultrasound (PAUT) imaging system of claim 20 wherein the electronic pulses are a first type of electronic pulses and the plane wave forming module further comprises: a FMC acquisition unit configured to transmit the first type of electronic pulses, the first type of electronic pulses configured to cause each of the P transmitters to individually transmit ultrasound energy, and the FMC acquisition unit further configured to receive the response signals from each of the Q receivers, thereby forming a FMC matrix of the P×Q response signals; and, a plane wave calculation unit configured to calculate the plane wave FMC matrix from the FMC matrix, the plane wave FMC matrix being equivalent to transmission of the N transmitted plane waves and reception of the M received plane waves. ### Claim 22 (depends on 20) The phased array ultrasound (PAUT) imaging system of claim 20 wherein the electronic pulses are a second type of electronic pulses and the plane wave forming module further comprises: a plane wave generating unit configured to transmit the second type electronic pulses, the second type of electronic pulses configured to cause emission of the N transmitted plane waves from the P transmitters; a plane wave receiving unit configured to receive the response signals, wherein the response signals from each of the N transmitted plane waves are received as the M received plane waves, and wherein the response signals from corresponding transmitted plane waves and received plane waves are combined to form the plane wave FMC matrix.