A cervix probe is equipped with a tactile sensor array and an ultrasound transducer and configured for simultaneous acquisition of stress data and ultrasound strain data for the same sector of the cervix. Acquired and recorded stress and strain data are transmitted to a data processor for calculating cervix elasticity and cervix length, followed by calculating a probability of spontaneous preterm delivery using a clinically validated predictive model.

Transducers are provided including a piezoelectric block having first and second opposing surfaces; a first conductive flexible support layer on the first surface of the piezoelectric block, the first flexible support layer having a first thickness; and a second flexible support layer on the second surface of the piezoelectric block, the second flexible support layer having a second thickness. Related devices are also provided.

An acoustic matching structure is used to increase the power radiated from a transducing element with a higher impedance into a surrounding acoustic medium with a lower acoustic impedance. The acoustic matching structure consists of a thin, substantially planar cavity bounded by a two end walls and a side wall. The end walls of the cavity are formed by a blocking plate wall and a transducing element wall separated by a short distance (less than one quarter of the wavelength of acoustic waves in the surrounding medium at the operating frequency). The end walls and side wall bound a cavity with diameter approximately equal to half of the wavelength of acoustic waves in the surrounding medium. In operation, a transducing element generates acoustic oscillations in the fluid in the cavity. The transducing element may be an actuator which generates motion of an end wall in a direction perpendicular to the plane of the cavity to excite acoustic oscillations in the fluid in the cavity, and the cavity geometry and resonant amplification increase the amplitude of the resulting pressure oscillation. The cavity side wall or end walls contain at least one aperture positioned away from the center of the cavity to allow pressure waves to propagate into the surrounding acoustic medium.

An ultrasonic probe includes: a piezoelectric element that transmits and receives an ultrasonic wave; one or a plurality of acoustic matching layers disposed on a subject side of the piezoelectric element; and a conductor layer that applies a voltage to the piezoelectric element, wherein the conductor layer is disposed between the piezoelectric element and the acoustic matching layer, or between the plurality of acoustic matching layers, a magnitude of an acoustic impedance of the conductor layer is between a magnitude of an acoustic impedance of a layer disposed on one surface side of the conductor layer and a magnitude of an acoustic impedance of a layer disposed on the other surface side of the conductor layer, and the conductor layer has a Vickers hardness (Hv) of 50 or more and 600 or less.

A curvilinear ultrasound transducer and a method of manufacturing the same. The method includes providing a piezoelectric block having an upper side and a lower side opposite to the upper side; cutting the piezoelectric block at a plurality of positions forming a plurality of ultrasound transducer elements, the plurality of ultrasound transducer elements separated by a plurality of gaps; allowing the plurality of gaps to be filled with a first gas resulting in a plurality of gas-filled gaps; arranging an acoustic matching layer facing the upper side of the piezoelectric block; arranging the piezoelectric block and the first acoustic matching layer between a curvilinear upper surface of a support structure and a pressure element; and pressing the piezoelectric block and the first acoustic matching layer with the support structure and the pressure element to curvilinearly shape the piezoelectric block and first acoustic matching layer.

Methods for fabricating high frequency ultrasound transducers are disclosed. The methods include fabricating an acoustic lens layer with a curved center section and two flat side sections. The curved section includes a center portion with a midpoint and an edge. The midpoint has a first thickness, and the edge has a second thickness. The center portion is fabricated so that an average of the first and second thicknesses is approximately equal to an odd multiple of a quarter-wavelength of the center frequency of the ultrasound transducer. The methods can also include bonding the lens layer to a matching layer that is operationally coupled to a transducer layer. The matching layer can include an epoxy layer and another layer. Bonding the lens layer includes bonding the other layer to the lens layer using the epoxy layer such that the other layer is positioned between the epoxy layer and the transducer layer.

A downhole transducer can include at least one single-crystal piezoelectric material, the at least one single-crystal piezoelectric material being positioned in the downhole transducer that is deployed downhole in a wellbore. Additionally, the downhole transducer can include at least one pair of electrodes positioned adjacent to the at least one single-crystal piezoelectric material for determining wellbore parameter measurements using one or more acoustic signals transmitted in the wellbore. The single-crystal piezoelectric material can include PIN-PZN-PT.

Examples herein include piezoelectric layers of an ultrasound transducer, ultrasound transducers, methods of manufacturing the transducers, and methods of manufacturing the piezoelectric layers of an ultrasound transducer. In one example, a piezoelectric layer of an ultrasound transducer include a non-metallic frame and a piezoelectric material. The non-metallic frame surrounds the piezoelectric material on at least two sides and is coupled to a lens support structure with a structure such that an acoustic lens and the piezoelectric material are oriented substantially parallel to each other. The piezoelectric material is sized to span an area greater than or equal to an active surface of the acoustic lens.

A fluid impermeable transducer includes an assembly of a transducer head and a casing, and an actuator disposed in the casing rearward of the back of the transducer head and operable to transmit acoustic energy through the transducer head. The transducer head and casing define a working portion of the transducer that is fluid impermeable.

A backing material for an ultrasonic probe according to the present invention comprises a carbonaceous matrix that has communicating holes distributed in the matrix, and a resin with which the communicating holes are filled.