| 摘要 |
A piezoelectric element has a very small size, has a high coefficient of electromechanical coupling, and can easily be impedance-matched to a circuit. An interdigital electrode, including two comb-shaped electrodes, is provided on one surface of a plate-like piezoelectric member, and similarly, an interdigital electrode, including two comb-shaped electrodes, is provided on another surface of the plate-like piezoelectric member. The piezoelectric member is polarized by applying electrical fields between the two respective pairs of comb-shaped electrodes; and in addition, by applying an electrical field for excitation between a terminal connecting one of the comb-shaped electrodes to each interdigital electrode, and another terminal connecting the other comb-shaped electrodes to each interdigital electrode, longitudinal vibrations in a stiffened mode are excited, whereby the piezoelectric member expands and contracts in the longitudinal direction thereof.
|
