| 摘要 |
PROBLEM TO BE SOLVED: To obtain a zoom lens by which excellent variable power and miniaturization are made compatible without causing the increase of a cost and power consumption at the time of operating a lens by executing focusing for a finite distance object by a new method. SOLUTION: This zoom lens is provided with a first group 1 having a positive focal distance, a second group 2 having a negative focal distance, a third group 3 having the positive focal distance and a fourth group 4 having the positive focal distance in this order from an object side. The second group 2 is monotonously moved from the object side to an image side, and the fourth group 4 is monotonously moved from the image side to the object side at the time of zooming from a short focus end to a long focus end. In this case, the focusing for the finite distance object is executed by the movement of the fourth group 4 at least at the short focus end, and is executed by the movement of the second group 2 at least at the long focus end.
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