Driving device for oscillatory actuator

摘要

A driving device for an oscillatory actuator in which a FLL (Frequency Locked Loop) is employed for detecting an electromotive force generated in a driving coil resulting from mechanical oscillation during a period in which no driving current is supplied to the oscillatory actuator, and for controlling an oscillation frequency on the basis of a relative time ratio between positive and negative polarities of the electromotive force to thereby pull a driving frequency into a neighborhood of a self-resonance frequency of the oscillatory actuator.