| 摘要 |
A zoom lens system capable of very close range photography comprises, in succession from the object side a convergent first lens group stationary during zooming and moved on the optical axis during focusing, a divergent second lens group which is a variator moved on the optical axis during zooming, a divergent third lens group which is a compensator moved on the optical axis during zooming, and a convergent fourth lens group which is a master lens stationary during zooming. Focusing in a normal photographing distance range is effected by moving the first lens group which is a focusing lens group in the direction of the optical axis. When focusing to an object lying at a shorter distance than the normal photographing distance, all of the first lens group, the second lens group and the third lens group are moved toward the object side in the direction of the optical axis, thereby effecting very close range focusing.
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