| 摘要 |
A wide-angle zoom lens system includes a negative first lens group, a positive second lens group, a negative third lens group and a positive fourth lens group), in this order from the object. Upon zooming from the short focal length extremity to the long focal length extremity, a distance between the negative first lens group and the positive second lens group decreases, a distance between the positive second lens group and the negative third lens group increases, and a distance between the negative third lens group and the positive fourth lens group decreases. The wide-angle zoom lens system satisfies the following conditions: <?in-line-formulae description="In-line Formulae" end="lead"?>1.3<|f1|/fw<1.7 (f1<0) (1)<?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>2.5<f4/fw<3.3 (2)<?in-line-formulae description="In-line Formulae" end="tail"?> wherein f 1 designates the focal length of the negative first lens group; f 4 designates the focal length of the positive fourth lens group; and fw designates the focal length of the entire wide-angle zoom lens system at the short focal length extremity.
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