Patent ID: 7605991

Claim:
A lens module comprising: a first lens assembly including at least one first lens; a first lens barrel receiving the first lens assembly therein; a second lens assembly including at least one second lens; a second lens barrel receiving the second lens assembly therein, the second lens barrel having a bottom with a through hole, and an inner thread; an elastic member elastically pressing the first lens barrel toward the second lens barrel; and a hollow holder receiving the elastic member and the first lens barrel therein, the holder having an outer thread, the second lens barrel being threadedly engaged with the holder; wherein, the first lens barrel has one of at least one straight, elongate guiding protrusion and at least one straight guiding groove on an outer wall thereof, and the holder has the other one of the at least one straight, elongate guiding protrusion and the at least one straight guiding groove in an inner wall thereof, the at least one guiding protrusion and the at least one guiding groove each extending along a direction parallel to a central axis of the first lens barrel, the at least one guiding protrusion being adapted for sliding in the at least one guiding groove; and wherein, the first lens barrel has one of at least one sloping portion and at least one sliding protrusion on an end face thereof facing toward the bottom of the second lens barrel, the second lens barrel has the other one of the at least one sloping portion and the at least one sliding protrusion on the bottom thereof, and the second lens barrel is threadedly movable relative to the holder, whereby the at least one sliding protrusion slides on the at least one sloping portion such that the first lens barrel together with the first lens assembly is forced to move relative to the second lens barrel together with the second lens assembly, movement of the first lens barrel together with the first lens assembly along a central axis of the lens module simultaneously accompanying movement of the second lens barrel together with the second lens assembly along the central axis of the lens module.