US Patent 8199421 Auto-focusing lens driving device

This invention provides an auto-focusing lens driving device having a movable member, the movable member comprising: a cylinder-shaped lens carrier whose exterior is wound with a coil and whose interior defines a hollow portion for receiving an optical system; and two separate conductive elastic pieces which are each disposed at one side of the cylinder-shaped lens carrier along an optical axis; wherein each one of the two ends of the coil is micro-welded and joined to a corresponding one of the two conductive elastic pieces by thermal pressing technique, and a thermal pressing region having an area of less than 1 mm2 is formed at the end of the coil.