| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve mechanical and electric performance and reliability of a laminated piezoelectric element, and to thin the diameter of an ultrasonic probe. <P>SOLUTION: An ultrasonic transducer 12 of the ultrasonic probe 2 is provided with the laminated piezoelectric element having piezoelectric bodies 30a to 30e, a laminated structure 34, where surface and back electrodes 31 and 32 and inner electrodes 33a to 33d are laminated alternately and side electrodes 36a and 36b formed on both confronted sides 35a and 35b of the laminated structure 34. Grooves 37a to 37d and 38a to 38d are formed entirely at end faces of the inner electrodes 33a to 33d exposed to both sides 35a and 35b, and they are filled with a conductive material 39 and an insulator 40. The conductive material 39 and the insulator 40 are arranged so as to have mechanical symmetry. The conductive material 39 and the insulator 40 have the same Young's modulus, rigidity ratio and Poisson's ratio, and have almost the same acoustic impedance. <P>COPYRIGHT: (C)2008,JPO&INPIT |
