| 摘要 |
PROBLEM TO BE SOLVED: To provide a vibrator optimum as a vibration actuator having excellent controllability, accuracy and durability, by reducing the unevenness in rigidity caused by an anisotropy due to a polarization of a piezoelectric element and making the vibrating amplitude excited by the actuator uniform. SOLUTION: The annular vibrator comprises a plurality of electrodes 3-1 disposed at a gap 3-3 in a circumferential direction on one side surface of a piezoelectric element 2, and polarizing areas polarized by these electrodes 3-1 in alternate directions in reverse polarities. The interval of the adjacent electrodes is twice or more as large as the thickness of the polarizing direction, and an electric field strength generating at the time of polarizing between the polarizing regions of the reverse polarities is the electric field strength or less generated at the time of polarizing between the polarizing regions of the reverse polarities. |
