Zoom lens mechanism

摘要

A zoom lens mechanism includes a switching lens group frame supporting a first sub-lens group frame and a second sub-lens group frame which support first and second sub-sub-lens groups, respectively; a lens group shift mechanism for causing the first and second sub-lens group frames to linearly move to a mutually close position or a mutually distant position, with respect to the optical axis direction, in accordance with relative rotation between the first sub-lens group frame and the second sub-lens group frame; and a focusing mechanism which integrally moves the first sub-lens group frame and the second sub-lens group frame in the optical axis direction while maintaining a distance therebetween after the first and the second sub-lens group frames are moved to one of the mutually close position and the mutually distant position by the lens group shift mechanism.