Imaging lens
AssigneeKantatsu Co., Ltd.
InventorsYoji KUBOTA, Kenichi KUBOTA, Hitoshi HIRANO, Tomohiro YONEZAWA
Life of this patent
Estimating the term…
Abstract
An imaging lens includes a first lens having positive refractive power; a second lens; a third lens; a fourth lens having positive refractive power; a fifth lens; a sixth lens; and a seventh lens, arranged in this order from an object side to an image plane side. The sixth lens is formed in a shape so that a surface thereof on the image plane side has a positive curvature radius. The seventh lens is formed in a shape so that a surface thereof on the image plane side and a surface thereof on the object side are aspheric. The imaging lens has a specific angle of view.
Claims20
An imaging lens comprising:
- a first lens having positive refractive power;
- a second lens;
- a third lens;
- a fourth lens having positive refractive power;
- a fifth lens;
- a sixth lens;
- and
- a seventh lens, arranged in this order from an object side to an image plane side,
- wherein said sixth lens is formed in a shape so that a surface thereof on the image plane side has a positive curvature radius,
- said seventh lens is formed in a shape so that a surface thereof on the image plane side and a surface thereof on the object side are aspheric;
- and
- said imaging lens has an angle of view 2ω so that the following conditional expression is satisfied:
- 80°≤2ω.
An imaging lens comprising:
- a first lens having positive refractive power;
- a second lens;
- a third lens;
- a fourth lens having positive refractive power;
- a fifth lens;
- a sixth lens;
- and
- a seventh lens, arranged in this order from an object side to an image plane side,
- wherein said sixth lens is formed in a shape so that a surface thereof on the object side and a surface thereof on the image plane side have positive curvature radii,
- said seventh lens is formed in a shape so that a surface thereof on the image plane side and a surface thereof on the object side are aspheric;
- and
- said fourth lens has a focal length f4 so that the following conditional expression is satisfied:
- 2<f4/f<15,
- where f is a focal length of a whole lens system.
Dependencies are inferred from the claim text.