| 摘要 |
PROBLEM TO BE SOLVED: To realize a zoom lens made very compact, yielding a wide viewing angle, having high performance and yielding sufficient resolving power. SOLUTION: In the zoom lens, a 1st group optical system G1 having negative power and a 2nd group optical system G2 having positive power are successively arranged on an object side, and a diaphragm FA integrally moving is provided on the object side of the 2nd group optical system G2. In the case of variable power from a short focus end to a long focus end, the 2nd group optical system G2 monotonously moves from an image side to the object side, and the 1st group optical system G1 moves to correct the fluctuation of an image surface position associated with the variable power. The 2nd group optical system G2 includes a three cemented lens constituted by arraying a 1st negative lens E5, a 2nd positive lens E6 and a 3rd negative lens E7 successively from the object side. The lens arranged nearest to the object side in the three cemented lens is a negative meniscus lens turning its concave surface toward the image side. COPYRIGHT: (C)2004,JPO&NCIPI
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