US Patent 7751134 Lens actuator, and electronic device using the same

A lens actuator is provided for moving a movable part including a lens, with respect to a fixed part in the optical axis direction of the lens. The lens actuator includes (a) a magnet disposed on the surface of the movable part facing the fixed part and magnetized in the optical axis direction, (b) a coil disposed on the surface of the fixed part facing the magnet, and (c) a pair of magnetic materials disposed on both sides of the magnet in the optical axis direction, to direct magnetic flux from the magnet toward the coil.