US Patent 7525739 Zoom lens module

A zoom lens module includes a lens barrel, a piezoelectric actuator, and at least two lens modules. The piezoelectric actuator is disposed within the lens barrel. The piezoelectric actuator includes a piezoelectric ceramic component and a sliding member. At least one of the lens modules is attached to the sliding member. The other lens module is fixed in the lens barrel. The piezoelectric ceramic component drives the sliding member to move in a selected direction along an optical axis of the zoom lens module, so that the at least one lens module is moved relative to the other lens module, thus changing the focus of the zoom lens module (e.g., zoom or widen).