Abstract: Rather than using a coaxial cable, a twisted pair of wires is provided for each element-to-beamformer connection. Differential mode signals are transmitted between the transducer element and the respective channel. A multi-layer element is used for operation with the differential mode signals. In catheters or other probes, coaxial cables are not used. Using differential mode signals over twisted pairs allows reduction or rejection of common mode cross-talk and/or interference.

Abstract: Rather than using a coaxial cable, a twisted pair of wires is provided for each element-to-beamformer connection. Differential mode signals are transmitted between the transducer element and the respective channel. A multi-layer element is used for operation with the differential mode signals. In catheters or other probes, coaxial cables are not used. Using differential mode signals over twisted pairs allows reduction or rejection of common mode cross-talk and/or interference.

Abstract: Rather than using a coaxial cable, a twisted pair of wires is provided for each element-to-beamformer connection. Differential mode signals are transmitted between the transducer element and the respective channel. A multi-layer element is used for operation with the differential mode signals. In catheters or other probes, coaxial cables are not used. Using differential mode signals over twisted pairs allows reduction or rejection of common mode cross-talk and/or interference.

Abstract: A multi-layer transducer operates with only one system channel per element. Passive switching connects the layers differently for transmit than for receive operation, such as connecting two layers in parallel for transmit and in series for receive. Any passive switching may be used, such as current and voltage limiting circuits. Tuning may be passively switched. Different tuning circuits are passively switched as a function of voltage level between transmit and receive operations.

Abstract: An irregular ultrasound sampling grid is reconstructed to a three-dimensional grid for imaging. Volume data acquired with a helix transducer includes a fractional offset of data spaced along one dimension, resulting in the irregular ultrasound sampling grid. To determine a voxel value for a grid point on a uniform grid, two adjacent planes are identified. The sample locations in the two planes are not aligned, being on the irregular ultrasound sampling grid. Hardware acceleration devices, such as a graphics processing unit, perform bilinear interpolation in each of the planes. The data of each plane is interpolated to the proper global azimuth-range coordinate corresponding with the grid point. The bilinearly interpolated values from each plane are then linearly interpolated to the grid point.

Abstract: Rather than using a coaxial cable, a twisted pair of wires is provided for each element-to-beamformer connection. Differential mode signals are transmitted between the transducer element and the respective channel. A multi-layer element is used for operation with the differential mode signals. In catheters or other probes, coaxial cables are not used. Using differential mode signals over twisted pairs allows reduction or rejection of common mode cross-talk and/or interference.

Abstract: An irregular ultrasound sampling grid is reconstructed to a three-dimensional grid for imaging. Volume data acquired with a helix transducer includes a fractional offset of data spaced along one dimension, resulting in the irregular ultrasound sampling grid. To determine a voxel value for a grid point on a uniform grid, two adjacent planes are identified. The sample locations in the two planes are not aligned, being on the irregular ultrasound sampling grid. Hardware acceleration devices, such as a graphics processing unit, perform bilinear interpolation in each of the planes. The data of each plane is interpolated to the proper global azimuth-range coordinate corresponding with the grid point. The bilinearly interpolated values from each plane are then linearly interpolated to the grid point.

Abstract: A transducer array includes two or more sub-arrays that move relative to each other. Position sensors on each of the sub-arrays provide spatial coordination for beamforming and/or image forming to yield extended field of view and high image resolution. The adaptable transducer array, such as mounted on a flexible transducer housing, allows the array to better conform to the patient during internal or external use.

Abstract: A medical diagnostic ultrasound transducer system has at least a first and a second set of transducer layers of an element. Each set has one or more transducer layers with independent electrical access. A transmit event through a first set of transducer layers with broadband electrical signals generates acoustic signals containing at least two different frequency bands, and a receive event through a second and different set of transducer layers receives multiple tissue harmonic signals to generate a wide bandwidth response. Fundamental signals can be reduced with a pulse inversion technique through a second transmit event of inverted pulses, a second receive event and superposition of signals from the two receive events.

Abstract: A transducer array is connected with a catheter housing. As the transducer array is rotated, the catheter housing also rotates. As a result, at least a portion of the catheter housing twists about a longitudinal axis. By applying rotation in a controlled way, such as with a motor, a plurality of two-dimensional images for three-dimensional reconstruction may be obtained. The rotation of the catheter housing may limit the total amount of rotation of the array, such as rotating the array through a 90 degree or less amount of rotation about the longitudinal axis. The housing of the catheter is formed with a soft section. The softer material allows for a greater amount or increased ease for twisting the catheter.

Abstract: A transducer array is connected with a catheter housing. As the transducer array is rotated, the catheter housing also rotates. As a result, at least a portion of the catheter housing twists about a longitudinal axis. By applying rotation in a controlled way, such as with a motor, a plurality of two-dimensional images for three-dimensional reconstruction may be obtained. The rotation of the catheter housing may limit the total amount of rotation of the array, such as rotating the array through a 90 degree or less amount of rotation about the longitudinal axis. The housing of the catheter is formed with a soft section. The softer material allows for a greater amount or increased ease for twisting the catheter.

Abstract: A multi-layer transducer operates with only one system channel per element. Passive switching connects the layers differently for transmit than for receive operation, such as connecting two layers in parallel for transmit and in series for receive. Any passive switching may be used, such as current and voltage limiting circuits. Tuning may be passively switched. Different tuning circuits are passively switched as a function of voltage level between transmit and receive operations.

Abstract: Endocavity and invasive catheter transducers for four-dimensional or other imaging are provided. A two-dimensional or other multi-dimensional array of elements is connected with a minimum number of conductors to an imaging system. One or more conductors are used to select an aperture, such as selecting one or more rows of elements for activation. Along a different axis, such as an orthogonal axis, elements are used to image a planar region. By electronically switching the selected aperture, different planes are rapidly imaged. A matrix configuration of electrodes, such as using column electrodes for phased array imaging and row electrodes for selecting an elevation aperture allows for rapid acquisition of ultrasound data.

Abstract: A transducer array includes two or more sub-arrays that move relative to each other. Position sensors on each of the sub-arrays provide spatial coordination for beamforming and/or image forming to yield extended field of view and high image resolution. The adaptable transducer array, such as mounted on a flexible transducer housing, allows the array to better conform to the patient during internal or external use.

Abstract: A medical diagnostic ultrasound transducer system has at least a first and a second set of transducer layers of an element. Each set has one or more transducer layers with independent electrical access. A transmit event through a first set of transducer layers with broadband electrical signals generates acoustic signals containing at least two different frequency bands, and a receive event through a second and different set of transducer layers receives multiple tissue harmonic signals to generate a wide bandwidth response. Fundamental signals can be reduced with a pulse inversion technique through a second transmit event of inverted pulses, a second receive event and superposition of signals from the two receive events.

Abstract: Endocavity and invasive catheter transducers for four-dimensional or other imaging are provided. A two-dimensional or other multi-dimensional array of elements is connected with a minimum number of conductors to an imaging system. One or more conductors are used to select an aperture, such as selecting one or more rows of elements for activation. Along a different axis, such as an orthogonal axis, elements are used to image a planar region. By electronically switching the selected aperture, different planes are rapidly imaged. A matrix configuration of electrodes, such as using column electrodes for phased array imaging and row electrodes for selecting an elevation aperture allows for rapid acquisition of ultrasound data.

Abstract: A method for imaging a target includes the steps of transmitting ultrasonic energy at a fundamental frequency and receiving reflected ultrasonic energy at a harmonic of the fundamental frequency. The ultrasonic energy is transmitted in power bursts, each having a respective envelope shape, wherein the envelope shapes rise gradually to a respective maximum value and fall gradually from the respective maximum value. Ultrasonic energy in the transmit beam is focused in an elongated high power region, as for example by means of a line focus.

Abstract: A method for imaging a target includes the steps of transmitting ultrasonic energy at a fundamental frequency and receiving reflected ultrasonic energy at a harmonic of the fundamental frequency. The ultrasonic energy is transmitted in power bursts, each having a respective envelope shape, wherein the envelope shapes rise gradually to a respective maximum value and fall gradually from the respective maximum value. Ultrasonic energy in the transmit beam is focused in an elongated high power region, as for example by means of a line focus.

Abstract: A transmit beamformer includes multiple transducers, each responsive to a respective transmit waveform to produce a respective transducer waveform. A transmit waveform generator generates the transmit waveforms, and the transmit waveforms each include multiple frequency components. Progressively higher frequency components of the transmit waveforms are timed to cause corresponding progressively higher frequency components of the transducer waveforms to focus along a line at progressively shorter ranges. In this way, a frequency dependent line focus is achieved.

Abstract: A transmit beamformer includes multiple transducers, each responsive to a respective transmit waveform to produce a respective transducer waveform. A transmit waveform generator generates the transmit waveforms, and the transmit waveform each include multiple frequency components. Progressively higher frequency components of the transmit waveform are timed to cause corresponding progressively higher frequency components of the transducer waveforms to focus along a line at progressively shorter ranges. In this way, a frequency dependent line focus is achieved.