A scanning apparatus for imaging an object, comprising an ultrasound transducer comprising a transmitter configured to transmit ultrasound signals in a first direction towards an object and a receiver configured to receive reflected ultrasound signals from an object; and a backing block for absorbing ultrasound signals, located adjacent the transducer along a second direction opposite to the first direction; the backing block comprising an inner surface facing the transducer, the inner surface comprising a non-planar feature configured to increase the absorption of ultrasound signals by the backing block.

Electroacoustic device (5) comprising: an ultrasonic wave transducer (15) comprising a piezoelectric substrate (10) and first (30) and second (35) electrodes in contact with the piezoelectric substrate, and a carrier (10), the transducer being attached to the carrier and acoustically coupled to the carrier, and the first and second electrodes being sandwiched, at least partly, between the piezoelectric substrate and the carrier, the device being configured to generate an ultrasonic surface wave (W) propagating through the carrier at a distance from the transducer when an electric current passes through the first and second electrodes.

Some disclosed implementations include an ultrasonic sensor stack and an acoustic resonator. The acoustic resonator may be configured to enhance ultrasonic waves transmitted by the ultrasonic sensor stack in an ultrasonic frequency range that is suitable for ultrasonic fingerprint sensors. In some examples, the acoustic resonator may include one or more low-impedance layers residing between a first higher-impedance layer and a second higher-impedance layer. Each of the one or more low-impedance layers may have a lower acoustic impedance than an acoustic impedance of the first higher-impedance layer or an acoustic impedance of the second higher-impedance layer. At least one low-impedance layer may have a thickness corresponding to a multiple of a half wavelength at a peak frequency of the acoustic resonator. The peak frequency may be within a frequency range from 1 MHz. to 20 MHz.

An acoustic lens contains a base material composed of a diorganopolysiloxane or a silicone rubber compound utilizing a diorganopolysiloxane as a main component, and plate-like inorganic compound particles dispersed in the base material.

An ultrasonic sensor that is less affected by humidity change is obtained. Ultrasonic sensor (1) is configured by sequentially laminating piezoelectric element (2), metal housing (3), first acoustic matching layer (4), and second acoustic matching layer (5). First acoustic matching layer (4) adjacent to piezoelectric element (2) with metal housing (3) interposed therebetween includes a thermoplastic resin and an inorganic filler. The weight fraction of the inorganic filler in first acoustic matching layer (4) is set to less than or equal to 30% and the weight fraction of the hollow structure filler in the inorganic filler is set to less than or equal to 50%.

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.

The objective of this invention is to provide an ultrasonic-wave transmitter/receiver fish-finder that stabilizes its balanced state while in water to transmit ultrasonic waves vertically downward, thus improving detection accuracy. The ultrasonic-wave transmitter/receiver 10 includes an ultrasonic transducer 21 that transmits and receives ultrasonic waves; a hanging-bell shaped case 50 that houses the ultrasonic transducer 21; and a cable 40 that suspends the case 50. A weight 81 is arranged above the ultrasonic transducer 21 provided at the bottom 54 of the case 50. In addition, the filler A1 is filled into the case 50 such that a cavity A2 is secured in the upper region of the case 50.

An ultrasonic transducer is described, including a piezoelectric element, a fluid medium contact layer, a matching layer between the piezoelectric element and the fluid medium contact layer, and a backing layer. Ultrasound sensor devices utilising the ultrasonic transducer are also described, for use in systems for analysing a fluid such as milk.

A sonicator system for sonicating materials in a sample array includes a transducer layer configured to emit acoustic energy; and a multifocus acoustic lens layer configured to focus the acoustic energy from the transducer layer to the sample array to thereby simultaneously sonicate materials in the sample array.

A method of designing and forming a piezoelectric ceramic crystal integrating an impedance matching region and a backing region. The method includes receiving one or more required operating parameters of the piezoelectric ceramic crystal for an application, iteratively modeling and simulating performance of one or more materials, structures, and gradients to utilize within the piezoelectric ceramic crystal, identifying at least one material, structure, or gradient that exhibits predicted performance that at least substantially achieves the one or more required operating parameters of the piezoelectric ceramic crystal, outputting a design of the piezoelectric ceramic crystal, and forming the piezoelectric ceramic crystal via one or more additive manufacturing processes.