Patent ID: 7561353

Claim:
A lens barrel cam mechanism including: a linearly movable member for holding an optical element and which can be moved in the optical axis direction of said optical element, said linearly movable member including a cam follower; and a rotary member rotatable relative to said linearly movable member and which can be also moved relatively to said optical axis direction, said rotary member having a cam groove with which said cam follower is slidably engaged formed on its circumferential surface, wherein said rotary member is rotated to guide said cam follower with said cam groove so that said linearly movable member is moved forward and backward in said optical axis direction, comprising: a gear portion provided at least a part of one end of a rotation axis direction of said rotary member, said gear portion being developed at the outside of a radius direction and having teeth on its outer periphery; and a cam groove opening portion provided by opening an end portion of said gear portion side of said cam groove to the end surface of said rotary member, wherein said cam groove opening portion and said gear portion are provided such that they become substantially coincident with each other on the same vertical plane vertical to said optical axis direction, and wherein the cam groove opening extends along a circumferential direction of the rotary member in the vertical plane.