| 摘要 |
PURPOSE:To increase sufficiently the polarization applying voltage, by forming the groove parts to a piezoelectric material to space plural electrodes from each other and therefore reducing the lateral coupling and the electrostatic capacity among those electrodes. CONSTITUTION:As shown by a cross section, a piezoelectric plate 5 is made of a piezoelectric ceramic material such as PZT, etc. and plural stripe electrodes 6 are formed on the surface of one side along with groove part 5a which spaces these electrodes 6 from each other. For the part 5a and electrode 6, a full-surface electrode is coated on one side of the plate 5 and then cut is given to the full-surface electrode to obtain plural stripe electrodes 6. In this case, the cut is formed up to the inside of the plate 5 to form groove part 5a. The internal polarization of the plate 5 is obtained by applying the polarization applying voltage between lead wires 7 and 8. The distribution of polarization is approximate to the distribution of internal electric field of the plate 5 which is obtained when the voltage is applied. |
