An ultrasound system comprising a probe adapted for emitting and receiving ultrasound waves inside a medium, and a processing unit connected to said probe and adapted for processing signals from the probe. The probe is configured so as to behave as a Fresnel lens for focusing the ultrasound waves. The processing unit analyses signals from the probe for sensing the medium at a plurality of focal points.

Systems, methods, and mechanisms for sound beam focal point determination within an acoustic medium may include propagating a first sound beam to intersect a second sound beam, where the second sound beam converges at a focal point. The first and second sound beams may originate from known locations. A direction of the first sound beam within the acoustic medium may be adjusted to produce a maximum amplitude of signals generated from nonlinear mixing of the first sound beam and the second sound beam, where the maximum amplitude may correspond to the intersection of the first sound beam with the focal point of the second sound beam. A location of the intersection may be determined, at least in some instances, based on the known locations, the adjusted direction of the first sound beam, and a direction of the second sound beam.

Asymmetry is provided for the pushing pulse in acoustic radiation force impulse (ARFI) imaging. MI is based on the negative pressure. By increasing the positive pressure more than the negative pressure, the magnitude of displacement may be increased without exceeding the MI limit. Similarly, negative voltages depole while positive do not, so using an ARFI or pushing pulse with asymmetric positive-to-negative peak pressures or voltages allows for generation of greater magnitude of displacement without harm to the transducer.

An ultrasound measurement device includes: a processing device and multiple ultrasound sensors that capture tomographic information of a physiological structure. The ultrasound sensors include a first ultrasound sensor including a first transducer having a first frequency response with a first resonant frequency, and a second ultrasound sensor including a second transducer having a second frequency response with a second resonant frequency different from the first resonant frequency. The first frequency response partially overlaps with the second frequency response. The second transducer transmits an ultrasound signal that is reflected by the physiological structure to create a reflected ultrasound signal, the first transducer generates a first received signal from the reflected ultrasound signal, the second transducer generates a second received signal from the reflected ultrasound signal, and the processing device normalizes the first received signal with the second received signal or the second received signal with the first received signal.

A rotational intravascular ultrasound probe for insertion into a vasculature and a method of manufacturing the same. The rotational intravascular ultrasound probe comprises an elongate catheter having a flexible body and an elongate transducer shaft disposed within the flexible body. The transducer shaft comprises a proximal end portion, a distal end portion, a drive shaft extending from the proximal end portion to the distal end portion, an ultrasonic transducer disposed near the distal end portion for obtaining a circumferential image through rotation, and a transducer housing molded to the drive shaft and the ultrasonic transducer.

A control unit cyclically sets a first transmission/reception condition for a close range and a second transmission/reception condition for a long range. A synthesizing unit generates an added frame sequence and an edge-enhanced frame sequence from a reception frame sequence, and generates a synthesized frame sequence from the added frame sequence and the edge-enhanced frame sequence. The first transmission/reception condition includes a first transmission frequency and a first transmission depth of focus. The second transmission/reception condition includes a second transmission frequency that is lower than the first transmission frequency and a second transmission depth of focus that is greater than the first transmission depth of focus.

Techniques, systems, and devices are disclosed for ultrasound diagnostics using spread spectrum, coherent, frequency- and/or phase-coded waveforms. In one aspect, a method includes synthesizing individual orthogonal coded waveforms to form a composite waveform for transmission toward a biological material of interest, in which the synthesized individual orthogonal coded waveforms correspond to distinct frequency bands and include one or both of frequency-coded or phase-coded waveforms; transmitting a composite acoustic waveform toward the biological material of interest, where the transmitting includes transducing the individual orthogonal coded waveforms into corresponding acoustic waveforms to form the composite acoustic waveform; receiving acoustic waveforms returned from at least part of the biological material of interest corresponding to at least some of the transmitted acoustic waveforms that form the composite acoustic waveform; and processing the received returned acoustic waveforms to produce an image of at least part of the biological material of interest.

Systems and methods for improving the quality of ultrasound images made up of a combination of multiple sub-images include giving more weight to sub-image information that is more likely to improve a combined image quality. Weighting factor information may be determined from the geometry (e.g., angle or path length) of a location of one or more specific transducer elements relative to a specific point within a region of interest or a region of an image. In some embodiments, any given pixel (or other discrete region of an image) may be formed by combining received echo data in a manner that gives more weight to data that is likely to improve image quality, and/or discounting or ignoring data that is likely to detract from image quality (e.g., by introducing noise or by increasing point spread).

For estimating attenuation, diffraction effects are corrected by transmitting at different frequencies using apertures sized to match the on-axis intensity profile and/or resolution cell size between the transmissions where there is no attenuation. Attenuation causes a variance in return. A rate of change is estimated from a ratio of the magnitude of the signals or displacements responsive to the transmissions. The attenuation is calculated from the rate of change over depth of the ratio.

A dual frequency ultrasound transducer includes a high frequency (HF) transducer and a low frequency (LF) transducer that is positioned behind the high frequency transducer. An intermediate layer is positioned between the low frequency transducer and the high frequency transducer to absorb high frequency ultrasound signals. An alignment feature on the low frequency transducer is positioned with respect to a fiducial that is marked at a known position with respect to high frequency transducer elements of the HF transducer to align low frequency transducer elements of the LF transducer with the HF transducer elements.