| 摘要 |
PROBLEM TO BE SOLVED: To obtain a compact zoom lens which is contrived in the shape of a lens surface so as to easily restrain the thickness of respective lens groups, easily secure space for focus movement by a third lens group, and easily restrain the thickness when it is collapsed. SOLUTION: The zoom lens comprises a first lens group G1 having a negative refractive power, a second lens group G2 having a positive refractive power and a third lens group G3 having a positive refractive power, wherein during zooming from a wide-angle end to a telephoto end, a space between the first lens group G1 and the second lens group G2 narrows, at least the second lens group G2 and the third lens group G3 move only toward an object side. The first lens group G1 is constituted of one negative lens and one positive lens, and the third lens group G3 is constituted of one positive lens. All of the lens surfaces exposed to the air on an optical axis in the zoom lens, except the lens surface nearest to the object side, have the paraxial center of curvature on an image side rather than the top of the lens surface. COPYRIGHT: (C)2008,JPO&INPIT
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