Compact zoom lens system
AssigneeOlympus Optical Co., Ltd.
InventorsJuro Kikuchi, Toshihiro Imai
Life of this patent
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Abstract
A compact zoom lens system comprising a first lens unit having negative refractive power and arranged as a movable lens unit, a second lens unit having positive refractive power and arranged as a movable lens unit, and a third lens unit arranged as a fixed lens unit, the compact zoom lens system being arranged that the third lens unit comprises a meniscus lens which is concave toward the object side and that aberrations are corrected favorably.
Claims6
A compact zoom lens system consisting of a first lens unit having negative refractive power and arranged as a movable lens unit, a second lens unit having positive refractive power and arranged as a movable lens unit, and a third lens unit arranged as a fixed lens unit, said third lens unit comprising a meniscus lens arranged to be concave toward the object side and said compact zoom lens system fulfilling the conditions (1), (2) and (3) shown below:
- .vertline.f.sub.3 .vertline.f.sub.W >10 (1)
- r.sub.a .apprxeq.r.sub.b ( 2)
- f.sub.3 >0 (3)
- where, reference symbol f.sub.3 represents the focal length of said third lens unit, and reference symbol f.sub.W represents the focal length of the lens system as a whole in the wide position, and where reference symbol r.sub.a and r.sub.b respectively represent radii of curvature of respective surfaces of said third lens unit.
Dependencies are inferred from the claim text.