Patent ID: 7262927

Claim:
An auto-focus lens module comprising a base that is a rectangular frame with four stands on four corners for fastening with a top cover while an insertion hole is on center thereof to form an opening in optical pathway of lens; two fixing holes are disposed on two opposite angles of inner surface of the base; two guide pins respectively vertically mounted and fixed into the two fixing holes on inner surface of the base; two conductive plates disposed on the base, respectively connect to different electrodes and a central hole is mounted between the two conductive plates so as to form an opening in optical pathway of the lens; an insertion hole is disposed on each of the conductive plates for being assembled with corresponding guide pin; a bottom plate having with a central hole on the center thereof to form an opening in the optical pathway of lens disposed over the two conductive plates; a lens holder having a circular frame, two symmetrical lugs on edges of the frame and a central hole for accommodation of a lens; an insertion hole for assembling with the guide pin is disposed on each of the two lugs; two springs assembled with the two guide pins respectively and the bottom side thereof presses against the two symmetrical lugs of the lens holder; the lens mounted and fixed on the central hole of the lens holder; a coil disposed on the circular frame of the lens holder and the head end as well as tail end of the coil connects the two conductive plates respectively; a top plate having a circular frame and two fastening members on edges of the circular frame; by the two fastening members locking with the lens holder, the top plate, the coil and the lens holder are disposed on circumference of the lens so as to form a lens holder set while the coil is clipped and fixed between the circular frame of the top plate and the corresponding circular frame of the lens holder; two magnets that are symmetrical arched magnets clip on right and left sides of the coil respectively; and a top cover in combination with the base to form a lens module; the two magnets locates between the top cover and the bottom plate while the two springs respectively presses against the inner surface of the top cover and thus being mounted between the inner surface of the top cover and the lug of the lens holder; thereby the lens holder set is driven axially by electromagnetic force generated from the interaction between the coil and the magnets while the two springs assembled on the guide pin, elastically against between the lens holder set and the inner surface of the top cover make the lens holder set move stably in axial direction.