DRIVING METHOD OF VIBRATOR, VIBRATING DEVICE, AND DRIVING DEVICE, DUST REMOVER AND OPTICAL APPARATUS WITH VIBRATING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a vibrator driving method for efficiently moving an object containing dust by vibrations in a predetermined direction.

SOLUTION: The vibrator driving method causes a vibrator to generate standing waves different in order with a predetermined time phase difference. The vibrator has a first vibration mode in which plural nodal lines are arranged in a first direction, a second vibration mode in which the number of first-direction nodal lines is different from that in the first vibration mode and its natural frequency is higher than that of the first vibration mode, and a third vibration mode in which its natural frequency is between those of the first and second vibration modes. The vibrator is driven on condition that excitation force to one of the first and second vibration modes in which a difference between its natural frequency and the natural frequency of the third vibration mode is smaller is made larger than that to the other thereof in which a difference between its natural frequency and the natural frequency of the third vibration mode is larger.

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