| 摘要 |
Provided is an ultrasonic transducer capable of emitting an ultrasonic wave of a high sound pressure and having a preferable reverberation characteristic. The ultrasonic transducer (10) includes a cap body (12) of a bottom-equipped cylindrical shape. A piezoelectric element (14) is attached to a bottom (12a) in the cap body (12) by conductive adhesive or the like. An internal frame (16) formed by a material having an acoustic impedance greater than the cap body is engaged inside the cap body (12). The internal frame (16) is engaged so as to be in intimate contact with a side surface (12b) including the end portion of the cap body (12). A through hole (22) is formed in the side surface of the internal frame (16). Lead lines (24a, 24b) are connected to the piezoelectric element (14) and the internal frame (16). The internal frame (16) has an interior filled with a sound absorbing material (26) and a vibration control material (28). Through the through hole (22) of the internal frame (16), the vibration control material (28) is brought into a direct contact with the side surface (12a) of the cap body (12). |
