Patent ID: 7382510

Claim:
An actuator of the type employing a two-degree-of-freedom vibration system, the actuator comprising: a first mass portion; a second mass portion; a supporting portion; at least a pair of first elastic connecting portions which connect the first mass portion to the supporting portion so that the first mass portion can rotate with respect to the supporting portion; and at least a pair of second elastic connecting portions which connect the second mass portion to the first mass portion so that the second mass portion can rotate with respect to the first mass portion, wherein the first mass portion is driven by the application of an alternating voltage, causing the second mass portion to rotate, and the frequency of the alternating voltage is set so as to be substantially the same as a lower resonance frequency of resonance frequencies of the two-degree-of-freedom vibration system at which the first mass portion and the second mass portion resonate, and wherein at least one of the pair of first elastic connecting portions and the pair of second elastic connecting portions includes a piezoresistive element.