Patent ID: 8009372
Filing Date: 2011-08-30
Classification: G02B,G03B

Abstract:
1. A lens driving device comprising: an annular magnet carriage disposed on a base, in the magnet carriage at least one magnet and at least one coil are disposed; a lens holder for carrying a lens mounted in said coil, being movable forward and backward in said magnet carriage; two damping devices resisting the lens movement respectively disposed at front of and back of said lens holder to keep said lens holder balanced and stable, when the electromagnetic force generated by the powered coil overcomes the damping force generated by said damping devices, said lens holder is driven to move forward or backward along the optical axis of the lens; a limiting mechanism positioning disposed between said lens holder and said annular magnet carriage for preventing said lens holder from offsetting and moving; wherein said annular magnet carriage is externally-square-shaped with a central circular hole and having a hollowed-U-shaped section, so as to form an externally-square-shaped and internally circular-shaped cavity; while said magnet being disposed in the corner of said cavity; said two damping devices comprise a front spring with a front gasket in front of said lens holder and a rear spring with a rear gasket in back of said lens holder, and said front gasket is mounted on a front sidewall of said cavity of the annular magnet carriage.