Microwave-induced thermoacoustic tomography was explored to image biological tissue. Short microwave pulses irradiated tissue to generate acoustic waves by thermoelastic expansion. The microwave-induced thermoacoustic waves were detected with a focused ultrasonic transducer. Each time-domain signal from the ultrasonic transducer represented a one-dimensional image along the acoustic axis of the...

The input electrical impedance behaves as a capacitive when a piezoelectric transducer is excited near its resonance frequency. In order to increase the energy transmission efficiency, a series or parallel inductor should be used to compensate the capacitive impedance of the piezoelectric transducer. In this paper, the effect of the series matching inductor on the electromechanical characterist...

A class V cymbal flextensional transducer is composed of a piezoceramic disc sandwiched between two cymbal-shaped shell endcaps. Depending on the type of piezoceramic, there exists a maximum voltage that can be reached without depolarisation, but also, at higher voltage levels, amplitude saturation can occur. In addition, there is a restriction imposed by the mechanical strength of the bonding ...

Partial discharge (PD) is the main cause of electric equipment degradation. PD location can provide the scientific direction and analysis for equipment condition monitoring. The phased-ultrasonic receiving-planar array transducer for PD location in transformer is studied in this paper. The operation environment and material properties of transducer are analyzed. The center frequency of transduc...

The recovery of the 3D path of the transducer used during an Intravascular Ultrasound (IVUS) examination is of primary importance to assess the exact 3D shape of the vessel under study. Traditionally, the reconstruction is done simply by stacking the images during the pullback, or more recently using biplane angiography to recover the vessel curvature. In this paper, we apply the formulation of...

In medical ultrasound imaging, the axial resolution is l i i t e d by the bandwidth of the transducer. The frequency response of the transducer usually peaks at its center frequency f, but falls off at higher and lower frequencies. In a linear frequency modulation (FM) pulse coding technique for imaging, the frequency can be swept across the entire bandwidth of the transducer. In this technique...

In December 2000 the Object Management Group (OMG) called for a proposal of a smart transducer interface. In response a new standard has been proposed that comprises a time-triggered transport service within the distributed smart transducer subsystem and a well-defined interface to a CORBA environment. This smart transducer standard has been adopted by the OMG in January 2002. The smart transdu...

Micro-rod YAG single crystals are the preferred laser for gain mediums with a high power. However, brittle fracture and crack damages easy to occur in grinding process of micro-rod due their large length-to-diameter ratio, brittleness, hardness. In this work, modal, frequency, harmonic response transducer under ultrasonic elliptical vibration analyzed by using finite element simulation. Then, m...

The design and optimization of high performance ultrasound imaging probes often needs a reliable model to provide performance estimates related to project upgrades. Finite Element Model (FEM) is the most powerful and comprehensive tool available for this application, but needs a very fine preliminary tuning procedure in order to obtain consistent results. This was described in our previous work...