Systems, devices, and methods for sparse synthetic aperture ultrasound (SSAU) imaging and/or range-Doppler applications are described. An example method for SAU imaging includes receiving, via a user interface, an input including an array topology comprising a particular N-dimensional arrangement of a plurality of transducer elements of the SAU system, an objective space, a function characterizing an imaging capability of the SAU system, and one or more constraints, generating, based on the input, an acoustic field over the objective space for each of the plurality of transducer elements of the array topology, selecting one or more transducer elements from the plurality of transducer elements of the array topology based on evaluation of the function, and providing for display, on the user interface, the selected one or more transducer elements that satisfy each of the one or more constraints.

A method of operating electro-acoustical transducers such as PMUTs involves applying to the transducer an excitation signal over an excitation interval, acquiring at the transducer a ring-down signal indicative of the ring-down behavior of the transducer after the end of the excitation interval, and calculating, as a function of said ring-down signal, a resonance frequency of the electro-acoustical transducer. A bias voltage of the electro-acoustical transducer can be controlled as a function of the resonance frequency. An acoustical signal received can be transduced into an electrical reception signal and a damping parameter of the electro-acoustical transducer can be calculated as a function of the ring-down signal so that a cross-correlation reference signal can be synthesized as a function of the resonance frequency and the damping ratio of the electro-acoustical transducer. Such a cross-correlation reference signal can be used for cross-correlation with the electrical reception signal to improve the reception quality.

An apparatus comprising an array of polymer-based capacitive micromachined ultrasonic transducers positioned on a substrate. The substrate may be at least substantially transparent to ionizing radiation, be flexible, and/or have walls positioned thereon to protect the transducers.

Micromachined ultrasonic transducers integrated with complementary metal oxide semiconductor (CMOS) substrates are described, as well as methods of fabricating such devices. Fabrication may involve two separate wafer bonding steps. Wafer bonding may be used to fabricate sealed cavities in a substrate. Wafer bonding may also be used to bond the substrate to another substrate, such as a CMOS wafer. At least the second wafer bonding may be performed at a low temperature.

A two-dimensional array ultrasound probe, which is enabled for ultrasonic reception operation of a continuous wave Doppler mode (C mode) and an imaging mode (B mode). The probe includes a reception circuit provided for each transducer and a first multiplexer; a plurality of first wires connected to the first multiplexer; a second wire connected to a plurality of first wires outside the array; switches that are provided to the second wire and that can be turned off to adapt to phasing addition units; a plurality of second multiplexers connected to the second wire and a plurality of first output ports for the first mode; and a plurality of second output ports that are connected to each region between the switches on the second wire and that are used in the second mode.

A sensor system for attachment to a casing includes at least one sensor element, where the sensor element is configured for detecting an environment property of an environment which, with the sensor system attached to the casing, is situated on the opposite side of the casing with respect to the sensor system. The sensor system also includes an encapsulation layer, where the sensor element is embedded in the encapsulation layer, and where the encapsulation layer has a contact surface for attaching the sensor system to the casing.

An ultrasonic transducer includes a membrane, a bottom electrode, and a plurality of cavities disposed between the membrane and the bottom electrode, each of the plurality of cavities corresponding to an individual transducer cell. Portions of the bottom electrode corresponding to each individual transducer cell are electrically isolated from one another. Each portion of the bottom electrode corresponds to each individual transducer that cell further includes a first bottom electrode portion and a second bottom electrode portion, the first and second bottom electrode portions electrically isolated from one another.

Ultrasonic transducers that are capable of generating increased levels of ultrasound, as well as receiving ultrasonic waves with increased sensitivity. The ultrasonic transducers include a back cover, a protective front cover, a backplate, and a vibrator film layer disposed between the backplate and the protective front cover. The backplate includes a plurality of grooves formed on a surface thereof facing the vibrator film layer. Each groove includes upper edges having cross-sectional contours that gradually tend toward the deepest part of the groove to allow a larger area of the backplate to be closer to the vibrator film layer, thereby increasing the resulting electric field, and, consequently, increasing the output power and sensitivity of the ultrasonic transducer.

A design process is used for designing a device comprising a plurality of micro-machined elements, each comprising a flexible membrane, the elements being arranged in a plane in a determined topology. The design process comprises a step of defining the determined topology so that it has a character compatible with a generic substrate having cavities, the characteristics of which are pre-established. Each flexible membrane of the micro-machined elements is associated with one cavity of the generic substrate. The present disclosure also relates to a fabrication process for fabricating a device comprising a plurality of micro-machined elements, and to this device itself, wherein only some of the pairs of cavities and flexible membranes are configured to form a set of functional micro-machined elements.

An MEMS airborne ultrasonic transducer system operating on a thermoacoustic principle to determine brain haemorrhage, includes: an RF transmitter and ultrasound receiver systems to transmit RF energy and receive ultrasound wave, respectively, an RF transmitter system having an RF signal generator, an RF amplifier and a horn antenna, and an ultrasound receiver system having a lock-in amplifier, a DC supply and two ultrasonic transducer arrays wirebonded to low noise amplifier (LNA) chips. The MEMS airborne ultrasonic transducer system determines brain haemorrhage based on detecting RF-induced, blood-originating, thermoacoustic ultrasound wave at the pulse modulation frequency.