A ultrasonic transducer assembly of an ultrasonic surgical instrument includes a horn, a piezoelectric stack positioned proximally of the horn and defining a longitudinal opening extending therethrough, a proximal end mass positioned proximally of the piezoelectric stack and defining a longitudinal opening, and a rod secured to the horn and extending proximally from the horn through the longitudinal opening of the piezoelectric stack and the longitudinal opening of the proximal end mass. The rod is secured to the proximal end mass to pre-compress the piezoelectric stack between the horn and the proximal end mass.

A transducer is provided, which includes an oscillator and a broadbanded matching circuit. In the oscillator, a peak frequency corresponding to a peak transmission sensitivity may separate from a center frequency in a given bandwidth, and a transmission sensitivity may increase as a frequency separates from the peak frequency with respect to the center frequency. The broadbanded matching circuit may be configured to perform an impedance matching so that the transmission sensitivity of the oscillator at the peak frequency becomes substantially equal to the transmission sensitivity of the oscillator at the center frequency.

Disclose displacement connectors of high bending stiffness, high-performance piezoelectric actuators and derivative devices made of such. The connector has circumferentially alternating recess housings which, when fitted with the intended piezoelectric active elements makes displacement actuators, approximately double (2), triple (3) or quadruple (4) the displacement of individual active elements without adversely jeopardizing their regenerative forces. The connector may take any overall cross-section and length to suit intended applications. Connector recesses can be configured to house piezoelectric elements of a wide variety of cross-sections and dimensions, including longitudinal mode stacks, transverse mode bars and/or tubes, single crystal blocks of suitable cut and dimensions and their bonded assemblages.

Disclosed is a broadband underwater acoustic transceiver device. The device can be used in particular for positioning, detection, range finding or underwater acoustic communication. The device coaxially combines, within a transceiver device, a Tonpilz transducer and a FFR transducer, the FFR being arranged in front of the transmission face/horn of the Tonpilz transducer. In such a configuration, the Tonpilz horn also acts as reflective tape for the FFR transducer, forming a common tape-horn element. Furthermore, an annular baffle surrounding the Tonpilz pillar creates a Helmholtz cavity for broadening the emission band towards the low frequencies.

A piezoelectric system for ultrasonic thermotherapy and electrotherapy comprises a first piezoelectric element, a proof mass, a second piezoelectric element and an output unit. The proof mass is disposed between the first piezoelectric element and the second piezoelectric element. The first piezoelectric element is powered by a power source to generate oscillation, which is transferred by the proof mass to the second piezoelectric element so as to cause the second piezoelectric element to move and generate power. The output unit comprises a connecting surface and a tip surface. The output unit is electronically connected with the second piezoelectric element, wherein the connecting surface is connected with the first piezoelectric element and the tip surface is formed in a tapered shape. The oscillation from the first piezoelectric element and the power generated by the second piezoelectric element are output through the tip surface.

A hybrid micromachined ultrasound transducer includes a piezoelectric micromachined transducer and a capacitive micromachined transducer. The capacitive micromachined transducer is vertically stacked with the piezoelectric micromachined transducer. The piezoelectric micromachined transducer and the capacitive micromachined transducer include a common shared electrode.

The present disclosure provides an ultrasonic transducer and a method for preparing a matching layer. The ultrasonic transducer may include a piezoelectric layer and a matching layer. The matching layer may be provided between the piezoelectric layer and an object to be measured, the piezoelectric layer may be acoustically matched with the object through the matching layer, and the piezoelectric layer may facilitate conversion between ultrasonic waves and electrical energy. A sound velocity in the matching layer may be in a gradient distribution in at least one direction. Through the gradient distribution of the sound velocity in the matching layer, ultrasonic waves of different frequencies may have the same wavelength. Thus, an acoustic matching between the piezoelectric layer of different structures and the human body tissues may be realized, which improves transmittance of the ultrasonic wave in the matching layer and increases a bandwidth of the ultrasonic transducer.

An ultrasonic transducer system and apparatus is provided. The ultrasonic transducer apparatus comprises an enclosure including an impedance matching member, at least one piezoelectric component, an adhesive material, and a backing member including a plurality of apertures disposed thereupon, the impedance matching member is coupled to a first surface of the at least one piezoelectric component and the backing member is coupled to a second surface of the at least one piezoelectric component, the first surface is diametrically opposed to the second surface, the adhesive material is disposed between the at least one piezoelectric component and the backing member for coupling the at least one piezoelectric component to the backing member, and between the at least one piezoelectric component and the impedance matching member for coupling the at least one piezoelectric component to the impedance matching member.

A novel mode of ultrasonic oscillation is generated in a Langevin ultrasonic transducer comprising a metal block, a metal block provided with a supporting means protruding in a ring shape on its side surface, and polarized piezoelectric elements fixed between these metal blocks, by connecting the ultrasonic transducer to a base via the supporting means, whereby supporting the ultrasonic transducer on the base in a restrained state, and applying to the piezoelectric elements a voltage having such frequency that the ultrasonic transducer generates an ultrasonic oscillation with back-and-forth motion in a direction perpendicular to plane surfaces of the piezoelectric elements which has no oscillation node within the ultrasonic transducer; this novel ultrasonic oscillation mode is utilized for performing ultrasonic machining methods as well as for ultrasonic transmission method.

A case, a piezoelectric vibrator, and a wire are provided. The case has a bottomed cylindrical shape, the case including a bottom portion and a side wall portion. The piezoelectric vibrator includes piezoelectric ceramic containing Ti and Zr, and is attached to the bottom portion inside the case. The wire is connected to the piezoelectric vibrator and extends to an outside of the case. A resonance frequency in a spreading vibration mode of the piezoelectric ceramic not attached to the bottom portion becomes minimum at a temperature in a range of about ?30? C. or higher and about 10? C. or lower. A cross-sectional porosity in any longitudinal cross section of the piezoelectric ceramic is about 1% or less.