Circumferential angle adjustment device for generatrix of cylindrical lens, and lens barrel equipped with circumferential angle adjustment device for generatrix of cylindrical lens

A circumferential angle adjustment device for a generatrix of a cylindrical lens, comprising:

• a lens holding tube which holds the cylindrical lens, the lens holding tube having an optical axis;
• an outer tube in which the lens holding tube is arranged at an inner periphery of the outer tube, the outer tube having a longitudinal through-hole, the longitudinal through-hole extending parallel to the optical axis;
• and
• a cam member which is provided at an outer periphery of the lens holding tube and has a cam surface eccentric with respect to a cam axis intersecting with the optical axis, the cam surface slidably engaging with an inner surface of the longitudinal through-hole so that the cam member moves in a direction parallel to the optical axis,
• wherein the lens holding tube is rotatably supported with respect to the outer tube in a circumferential direction of the optical axis.