ULTRASONIC TRANSDUCER

摘要

A piezoelectric element (3) is placed on the inner bottom surface of a closed-bottomed outer container (1), and an inner case (2) is placed inside the outer case (1). Vibration of the outer case (1) by the piezoelectric element is restrained by mass by using that surface (ultrasonic vibration acting surface) of the inner case (2) that faces the bottom surface of the outer case (1). A first cutout section (11) is provided in the ultrasonic vibration acting surface, at a portion facing the position where the piezoelectric element (3) is placed, and the first cutout section (11) flattens an ultrasonic beam generated by vibration of the piezoelectric element (3) and outer case (1). Also, second cutout sections (12a, 12b), line symmetrical about the major axis of the first cutout section (11), are formed at positions away from the first cutout section (11).