Patent ID: 8223441

Claim:
A lens barrel that holds a lens for photographing, comprising: a fixing frame that is provided with a cam groove in an inner circumferential surface of the fixing frame; and a drive frame that includes a cam follower formed on an outer circumferential surface of the drive frame and capable of being fitted in the cam groove, the drive frame being movable with respect to the fixing frame along an optical axis direction of the lens together with a movement of the cam follower along the cam groove, wherein the cam groove at least includes a first region with a first groove width and a second region with a second groove width that is larger than the first groove width, and an outer diameter of the cam follower in a short side direction is substantially equivalent to the first groove width in the first region and an outer diameter thereof in a long side direction is n times (n is a value larger than 1) as large as the outer diameter thereof in the short side direction, the lens barrel further comprising: a rectilinear frame that is arranged in a coaxial position with the fixing frame and is movable in the optical axis direction, wherein the rectilinear frame includes a protruded portion on an outer circumferential cylindrical surface of the rectilinear frame, the fixing frame includes a rectilinear groove capable of being fitted freely with the protruded portion and guiding a movement of the rectilinear frame in the optical axis direction while restricting a rotation of the rectilinear frame, and the rectilinear groove is formed so that at least a part of the rectilinear groove is superimposed with the cam groove.