An actuator includes a first barrel, a second barrel, a first magnetic portion, a second magnetic portion and a plurality of springs. The second barrel is received in the first barrel. The first magnetic portion and the second magnetic portion are arranged between the first barrel and the second barrel. The first magnetic portion is fixed to the first barrel. The second magnetic portion is fixed to the second barrel. The first magnetic portion is opposite to the second magnetic portion. The first and second magnetic portions cooperatively drive the second barrel to move in the first barrel on the plane perpendicular to a central axis of the first barrel. The springs are elastically connected to the first barrel and to the second barrel, to provide a restoring force between the first barrel and the second barrel when the first barrel is not coaxial with the second barrel.