Patent ID: 7898753

Claim:
An apparatus for driving a lens by electromagnetic force, applicable to a camera module, the apparatus comprising: a frame; a barrel, mounted on the frame such that the barrel is rotable on the frame, and the barrel comprising a first linkage structure; a lens holder holding a lens, the holder comprising a second linkage structure, coupled to the barrel through the second linkage structure and the first linkage structure, and being movable along a central axis of the barrel; a kicker, disposed on an external wall of the barrel; a plurality of electromagnets, mounted on the frame and the kicker, respectively; and a resilient element, anchored with the kicker and the frame; wherein when an electric power is applied to the electromagnets, an electromagnetic field is generated to produce a repulsion force or an attraction force between the electromagnets to move the kicker and the barrel, and the lens holder is driven by the second linkage structure through a movement of the first linkage structure to move the lens holder along the central axis from a first position to a second position; wherein when the electric power supplied to the electromagnets is disconnected, a resilience of the resilient element rotates the barrel to drive the lens holder by the second linkage structure through the first linkage structure to move along the central axis from the second position back to the first position.