Zoom lens and zoom lens barrel

Abstract

A zoom lens and zoom lens barrel superior in precision and excellent in manipulability is disclosed, and they have a feature of combination of plastic cam barrel that retains a high dimensional precision and brings about decrease in a manufacturing cost, with the reduced number of components associated with cam follower pins. The zoom lens is comprised of a plurality of groups of lenses, an adjusting ring rotated for zooming by a user, a cam barrel provided with cam grooves and capable of rotating due to turns of the adjusting ring, a linearly moving barrel provided with grooves for linear movement and unable to rotate, n frames for holding n of the groups of lenses (n is an integer), and cam follower pins fitted in the cam grooves and the grooves for linear movement and fixed the first to the n-th frames for correspondingly holding the first to the n-th groups of lenses, respectively. The cam barrel is molded of plastic and has the cam grooves defined in cross-sectional shapes widening toward the outer circumference, and the cam follower pins are elastically formed so as to be fitted in the cam grooves.