Characteristic analysis of a one-sided concave-type ultrasonic transducer

Abstract

A method to control the characteristics of an ultrasonic transducer by the shaping of a piezoelectric vibrator was suggested. A one-sided concave piezoelectric vibrator was shaped from a piezoelectric plate, and an ultrasonic transducer made of the vibrator was examined in order to study its characteristics. The multiple resonant modes distributed in a frequency range of about 0.5–2 MHz were obtained and the −6 dB bandwidth of the transducer was about 65%–72%. An acoustic field analysis model which takes into consideration the source strength depending on the thickness of the piezoelectric vibrator was derived, and the change in the acoustic field distribution with the driving frequency was calculated. The calculated results were in good agreement with the experimental results.