Patent ID: 7535662

Claim:
An auto-focus camera comprising: a stator comprising a stator core having a plurality of poles and at least a coil wound around the stator core; a rotor being rotatably disposed in the stator, having an inner thread formed on an inner surface thereof; and a lens unit being linearly movably received in the rotor, comprising a lens barrel and a lens mounted in the lens barrel, the lens barrel having an outer thread formed on an outer surface thereof and engaging with the inner thread of the rotor, and an internal thread formed on an inner surface thereof, the lens having an external thread formed on an outer surface thereof and engaging with the internal thread of the barrel; wherein when the rotor rotates, the lens barrel together with the lens has a linearly telescopic movement relative to the rotor, and wherein a relative position between the lens and the lens barrel is adjustable by rotating the lens relative to the lens barrel; and wherein the rotor comprises an annular shell and an annular permanent magnet secured on the shell, an outer circumferential surface of the shell has a diameter substantially equal to that of an outer circumferential surface of the permanent magnet, and the inner thread of the rotor is formed on an inner circumferential surface of the shell.