# US 8,465,431 B2 · Multi-dimensional CMUT array with integrated beamformation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,465,431 B2 - Document ID: US8465431B2 - Status: Granted - Kind: B2 - Application number: 11/788,614 - Filed: 2007-04-20 - Published: 2007-10-18 - Granted: 2013-06-18 - Earliest claimed: 2005-12-07 - Assignees: Siemens Medical Solutions USA, Inc. - Applicants: Christopher M. W. Daft; D-L Donald Liu; Paul A. Wagner; Igal Ladabaum - Inventors: Christopher M. W. Daft; D-L Donald Liu; Paul A. Wagner; Igal Ladabaum - Web page: https://patentgrep.com/patent/US8465431B2 ## CPC - G01S 15/8997: {using synthetic aperture techniques} - A61B 8/12: in body cavities or body tracts, e.g. by using catheters - A61B 8/4483: {characterised by features of the ultrasound transducer} - A61B 8/4488: {the transducer being a phased array} - A61B 8/483: {involving the acquisition of a 3D volume of data} - G01S 7/5208: {with integration of processing functions inside probe or scanhead} - G01S 15/8925: {the array being a two-dimensional transducer configuration, i.e. matrix or orthogonal linear arrays} - G01S 15/8927: {using simultaneously or sequentially two or more subarrays or subapertures} - G01S 15/8977: {using special techniques for image reconstruction, e.g. FFT, geometrical transformations, spatial deconvolution, time deconvolution} - G10K 11/346: {using phase variation} - A61B 8/4472: {Wireless probes} - G01S 7/52046: {Techniques for image enhancement involving transmitter or receiver (image enhancement by image data processing G06T5/00)} - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G10K: SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR ## Abstract To generate information representing a volume, co-arrays or synthetic transmit aperture process is performed in one dimension and beamforming is performed in another dimension. For example, a transmit aperture focuses in azimuth, but is unfocused or divergent in elevation. A multi-dimensional array receives reflected echoes. The echoes are beamformed for sub-arrays for focus in azimuth. The resulting partial beamformed information is provided to an imaging system from the probe housing for completion of beamforming at least in elevation. ## Claims ### Claim 1 A method for generating ultrasound information for three-dimensional imaging, the method comprising: transmitting acoustic energy substantially unfocused along a first dimension and focused along a second dimension different than the first dimension, the focused acoustic energy including a focus within an image region such that the transmission covers no more than four scan lines along the second dimension and the unfocused acoustic energy of the transmission covers ten or more scan lines along the first dimension; receiving, in response to the transmitting, with a multi-dimensional transducer array; initially beamforming in azimuth and not elevation for a two-dimensional receive aperture; and synthesizing a transmit aperture in elevation from an output of the beamforming. ### Claim 2 (depends on 1) The method of claim 1 wherein receiving comprises acquiring a set of data representing an elevation plane at an azimuth angle from a single transmit, and wherein beamforming comprises beamforming the data. ### Claim 3 (depends on 1) The method of claim 1 wherein beamforming comprises beamforming with a substantially fully sampled two-dimensional array of capacitive membrane ultrasound transducers. ### Claim 4 (depends on 1) The method of claim 1 wherein beamforming comprises partial beamforming in azimuth spaced sub-arrays, the partial beamforming within a transducer probe, and wherein synthesizing comprises synthesizing in elevation within an imaging system separate from the transducer probe. ### Claim 5 (depends on 1) The method of claim 1 wherein transmitting comprises repetitively transmitting acoustic energy substantially unfocused along elevation and focused along azimuth, and wherein receiving comprises repetitively receiving, in response to the transmitting, with a substantially fully sampled two-dimensional array of microelectromechanical elements. ### Claim 6 (depends on 1) The method of claim 1 further comprising: sigma-delta analog-to-digital converting received electrical signals, the beamforming and synthesizing operating on the converted electrical signals. ### Claim 7 (depends on 1) The method of claim 1 wherein the transmitting comprises transmitting from a half-pipe transmit aperture, and wherein receiving comprises receiving with a substantially fully sampled two-dimensional array of elements in a split receive aperture, the split receive aperture being across the half-pipe transmit aperture. ### Claim 8 (depends on 1) The method of claim 1 further comprising: increasing a signal-to-noise ratio of the synthesizing by spatial transmit coding, temporal coding prior to beamforming, compensating for motion, or combinations thereof. ### Claim 9 (depends on 1) The method of claim 1 wherein beamforming and synthesizing are responsive to data received with a two-dimensional array of capacitive membrane ultrasound transducers; further comprising: spatial coding by varying biases of the transducers. ### Claim 10 An ultrasound transducer array for medical diagnostic ultrasound imaging, the transducer array comprising: a probe housing; a two-dimensional grid of capacitive membrane ultrasound transducer elements on or within the probe housing; a plurality of receive channel circuits connected with the elements and operable to at least partially beamform along a first dimension, the receive channel circuits within the probe housing; and at least one transmit element separate from the elements of the two-dimensional grid, the transmit element configured to generate a beam substantially unfocused along a second dimension different from the first dimension and focused, with a focus within an image region, along the first dimension such that the beam covers less than five scan lines along the first dimension and covers ten or more scan lines along the second dimension. ### Claim 11 (depends on 10) The transducer array of claim 10 wherein the receive channel circuits are configured to output samplings along parallel lines in the second dimension. ### Claim 12 (depends on 10) The transducer array of claim 10 wherein the at least one transmit element comprises a plurality of elements outside a receive aperture of the transducer elements. ### Claim 13 (depends on 10) The transducer array of claim 10 wherein the at least one transmit element comprises a piezoelectric element. ### Claim 14 (depends on 10) The transducer array of claim 10 wherein the at least one transmit element comprises a half-pipe transmitter. ### Claim 15 (depends on 10) The transducer array of claim 10 wherein the at least one transmit element comprises a linear array of transmit elements spaced along the first dimension, and wherein the two-dimensional grid is separated by the linear array. ### Claim 16 (depends on 10) The transducer array of claim 10 wherein the receive channel circuits comprise sigma-delta analog-to-digital converters. ### Claim 17 (depends on 10) The transducer array of claim 10 wherein the receive channel circuits comprise a bias source operable to vary bias polarities for spatial coding. ### Claim 18 A method for generating ultrasound information for three-dimensional imaging, the method comprising: transmitting acoustic energy substantially focused, with a focus within an image region, along a first dimension and substantially unfocussed along a second dimension different than the first dimension such that the acoustic energy covers only four or fewer scan lines out of at least one hundred along the first dimension; partial receive beamforming, in sub-arrays of elements, first data generated in response to the transmitting, the partial receive beamforming forming second data representing a two-dimensional plane extending along the second dimension at an angle in the first dimension; and then beamforming the second data along the second dimension. ### Claim 19 (depends on 18) The method of claim 18 wherein partial receive beamforming comprises partial receive beamforming within a transducer probe, and wherein beamforming comprises beamforming in an imaging system separate from the transducer probe. ### Claim 20 An ultrasound transducer array for medical diagnostic ultrasound imaging, the transducer array comprising: a probe housing; a multi-dimensional grid of capacitive membrane ultrasound transducer elements on or within the probe housing, the elements on or in a substrate; a plurality of sigma-delta analog-to-digital converters on or in the substrate; a plurality of mixers on or in the substrate and electrically connected between the elements and the converters; and a plurality of receive channel circuits connected with the converters and operable to at least partially beamform along at least a first dimension, the receive channel circuits in the probe housing. ### Claim 21 (depends on 20) The ultrasound transducer of claim 20 further comprising a plurality of preamplifiers on or in the substrate and electrically connected between the elements and converters. ### Claim 22 (depends on 20) The ultrasound transducer of claim 20 wherein the receive channel circuits are on or in the substrate. ### Claim 23 (depends on 20) The ultrasound transducer of claim 20 wherein the elements are fully sampled in the multi-dimensional grid.