Porous Piezoelectric transducer for the low frequency of 50 kHz.

Abstract

Porous Pb (Zr, Ti) O₃ (P-PZT), characterizing a large g₃₃ constant, low acoustic impedance (Zo) and low Q compared with conventional (nonporous) PZT, is applied to the transducer of the resonance frequency of 50kHz. Because the frequency is adjusted in the thickness mode, the resonance impedance of the P-PZT transducer becomes high. The impedance is lowered by the transformer composed in the transducer. The characteristics of the P-PZT transducer evaluated in water show a lower Q, wider frequency band width and shorter rise/fall time of the acoustic response than the non porous PZT transducer.