Imaging lens
AssigneeKantatsu Co., Ltd.
InventorHuang ZHIYU
Life of this patent
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Abstract
There is provided an imaging lens with excellent optical characteristics which satisfies demand of a low profile and a low F-number. An imaging lens comprises in order from an object side to an image side, a first lens with positive refractive power being formed in a meniscus shape having an object-side surface being convex in a paraxial region, a second lens with positive refractive power in a paraxial region, a third lens with negative refractive power in a paraxial region, a fourth lens with positive refractive power in a paraxial region, a fifth lens having aspheric surfaces on both sides, and a sixth lens with negative refractive power having an image-side surface being concave in a paraxial region, and predetermined conditional expressions are satisfied.
Claims7
An imaging lens comprising in order from an object side to an image side,
- a first lens with positive refractive power being formed in a meniscus shape having an object-side surface being convex in a paraxial region,
- a second lens with positive refractive power in a paraxial region,
- a third lens with negative refractive power in a paraxial region,
- a fourth lens with positive refractive power in a paraxial region,
- a fifth lens having aspheric surfaces on both sides, and
- a sixth lens with negative refractive power having an image-side surface being concave in a paraxial region, wherein the following conditional expressions (1) and (2) are satisfied:
- 0.30<f1/f4<1.85 (1)
- −3.30<r6/f<−0.70 (2)
- where
- f1:
- a focal length of the first lens,
- f4:
- a focal length of the fourth lens,
- r6:
- a paraxial curvature radius of an image-side surface of the third lens, and
- f:
- a focal length of the overall optical system of the imaging lens.
Dependencies are inferred from the claim text.