Patent attributes
A lens driving device has a stationary part including an iron shell, a movable part including a lens holder for holding a lens therein, and a driving part for moving the movable part relative to the stationary part. The driving part includes a plurality of magnets fixed to the iron shell, and at least one coil fixed to the lens holder. The magnets are divided into at least two layers stacked in the direction of the optical axis of the lens and a plurality of groups along the circumferential direction of the lens. Each magnet is polarized in the radial direction of the lens. The polarities of two adjacent stacked magnetic poles in the same group are opposite to each other so as to cooperatively form a magnetic circuit in a plane parallel to the optical axis direction. The coil includes an axis about which the coil is wound. The coil axis is perpendicular to the optical axis. The coil has an upper part facing one layer of magnets and a lower part facing the other layer of magnets.