DRIVE METHOD OF PIEZOELECTRIC MATERIAL ACTUATOR, AND THE PIEZOELECTRIC MATERIAL ACTUATOR, AND DISK RECORDING/REPRODUCING APPARATUS USING THE ACTUATOR

摘要

PROBLEM TO BE SOLVED: To provide a method for stably maintain continuous displacement quantity over a long period, by making deterioration of polarization characteristics recover in a condition such that a piezoelectric material actuator produced by membrane technique for use as a piezoelectric material element is mounted in a disk apparatus or the like.;SOLUTION: The piezoelectric material element has a polarization-electric field hysteresis characteristics which are asymmetric with the absolute value different between values of positive/negative opposite electric field E_C2, E_C1, to be polarized in the film thickness direction further in the direction with the absolute value being small for the opposite electric field. as position control voltage Q1 for performing position control, by displacing the piezoelectric material element 1 in a direction orthogonal related to the film-thickness direction, voltage corresponding to an electric field 0.4 or smaller than a value of this opposite electric field is applied to the film-thickness direction of the piezoelectric material element 1, related to the direction with the absolute value large of the opposite electric field. Further polarization recovery voltage Q2, for making deterioration of polarization recover, is applied to be overlapped with the position control voltage Q1, and is applied to be switched therewith, or is applied when the position control voltage Q1 is not applied, so as to make the deterioration of the polarization recover.;COPYRIGHT: (C)2004,JPO