Patent ID: 7106961

Claim:
An advancing/retracting mechanism of a lens barrel, comprising: a rotatable ring which is rotatable about a rotational axis extending in a direction of an optical axis, and includes at least one rotation transfer groove located on an inner peripheral surface of said rotatable ring to extend generally parallel to said optical axis; an advancing/retracting guide ring positioned inside said rotatable ring to be non-rotatable, wherein said advancing/retracting guide ring includes at least one inclined lead slot which penetrates through said advancing/retracting guide ring and which is inclined with respect to both a circumferential direction of said advancing/retracting guide ring and said optical axis direction, and at least one circumferential slot which is communicatively connected with said inclined lead slot and which extends only in said circumferential direction of said advancing/retracting guide ring; a driven member having at least one follower engaged in said inclined lead slot and said circumferential slot, and further engaged in said rotation transfer groove so as not to move relative to said rotation transfer groove in a rotational direction of said rotatable ring and to be slidably movable in said rotation transfer groove in said optical axis direction; at least one optical element supported by said driven member; and a ring spring positioned inside said rotatable ring along an inner peripheral surface thereof and supported by said rotatable ring, said ring spring including at least one follower pressing portion which is engaged in said rotation transfer groove, and is resiliently deformable in said optical axis direction, wherein said follower is disengaged from said follower pressing portion of said ring spring, when said driven member and said rotatable ring are positioned relative to each other in said optical axis direction such that said follower is engaged in said inclined lead slot; and wherein said follower is engaged with said follower pressing portion and resiliently deforms said follower pressing portion by pressing said follower pressing portion against one of two opposed edges of said circumferential slot in said optical axis direction, when said driven member and said rotatable ring are positioned relative to each other in said optical axis direction so that said follower is engaged in said circumferential slot.