Zoom lens with aberration variation prevented for focusing

摘要

A focusing part in a wide-angle zoom lens. The focusing section of a wide angle zoom lens is composed, from the object end, of a diverging fixed lens group, a converging movable lens group and a converging fixed lens group. The movable lens group remains stationary during a zooming operation and moves along its optical axis toward an image when focusing from a distant object onto a nearer object. Aberrations remain unvaried even when focusing onto a nearby object. The converging fixed group furnishes a suitably positioned object point for a zooming section arranged behind the focusing section. The converging fixed lens group is composed of a plurality of lenses contributing to improvement in the image quality.