This kind of vibration actuator is, for example, provided in an interchangeable lens of a camera or the like and utilized as a driving motor that drives an autofocusing lens. However, space for mounting a circuit that provides driving signals for driving the vibration actuator is limited. Therefore, as illustrated in Patent Document 1, it is difficult to provide ideal sine waves. Consequently, there are cases in which stable driving is not possible.
Patent Document 1: Japanese Unexamined Patent Publication No. H9-163767
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