ZOOM LENS AND IMAGING APPARATUS INCLUDING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a compact zoom lens providing a wide field angle with a fewer number of lenses and a smaller front lens diameter.

SOLUTION: A zoom lens includes a first lens group having a negative refractive power; a second lens group having a positive refractive power; and a third lens group having a positive refractive power from an object side to an image side in order, in which the distance between the respective lens groups changes when performing zooming. The first lens group includes two lenses of a negative lens and a positive lens from the object side to the image side in order. Defining the focal length of the entire system at the wide angle end as fW; the focal length of the first lens group as f1; the focal length of the second lens group as f2; the imaging magnification of the second lens group at the telephoto end as β2T; the imaging magnification of the third lens group at the telephoto end as β3T; the imaging magnification of the second lens group at the wide angle end as β2W; and the imaging magnification of the third lens group at the wide angle end as β3W, the following requirements are satisfied: ¾f1/f2¾<1.0; 1.50<¾f2/fW¾<2.15; and 3.2<(β2T*β3W)/(β2W*β3T)<4.0.

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