Abstract: A lens-positioning device of a camera module designed to provide a focusing function or an optical zoom function. In the lens-positioning device, an actuating part includes a ring-shaped piezoelectric actuator and a rotating plate positioned on an upper surface of the piezoelectric actuator. A positioning part is provided with a hollow barrel holder and linearly moved in the direction of the optical axis of the lens upon rotation of the rotating plate. The hollow barrel holder contacts the upper surface of the rotating plate. A hollow housing receives the actuating part and the positioning part and having a guide means to guide the positioning part to be linearly moved in the direction of the optical axis of the lens. The lens-positioning device can have ultra-miniaturized size through the piezoelectric actuator, and a minute focusing can be realized through minute positioning of the lens, allowing high resolution and high sharpness images.

Abstract: The present invention relates to a lens driving device, more particularly, capable of adjusting an effective focal length determined by the relative distance of lenses in an optical device having a zooming function. In the lens driving device, a barrel unit has an internal space for containing a lens therein and a guide slot for allowing forward and backward movement of the lens through rotation of the barrel unit. A ring-shaped piezoelectric actuator unit is arranged adjacent to the barrel unit for being contracted or expanded radially in response to an external input signal. A drive member is mounted on the piezoelectric actuator unit and having a plurality of segments projected toward the barrel unit to contact the same.