| 发明名称 | Imaging lens | ||
| 摘要 | An imaging lens includes a first lens having positive refractive power; a second lens having negative refractive power; and a third lens having positive refractive power, arranged in this order from an object side to an image plane side. Further, the first lens is formed in a shape so that a curvature radius of a surface thereof on the object side is positive. The second lens is formed in a shape so that a curvature radius of a surface thereof on the object side is negative and a curvature radius of a surface thereof on the image plane side is positive. The third lens is formed in a shape so that a curvature radius of a surface thereof on the object side and a curvature radius of a surface thereof on the image plane side are both positive. | ||
| 申请公布号 | US9091793(B2) | 申请公布日期 | 2015.07.28 |
| 申请号 | US201213712235 | 申请日期 | 2012.12.12 |
| 申请人 | OPTICAL LOGIC INC.;KANTATSU CO., LTD. | 发明人 | Kubota Yoji;Kubota Kenichi;Hirano Hitoshi;Kurihara Ichiro;Yonezawa Tomohiro |
| 分类号 | G02B9/14;G02B3/00;G02B13/00 | 主分类号 | G02B9/14 |
| 代理机构 | Kubotera & Associates, LLC | 代理人 | Kubotera & Associates, LLC |
| 主权项 | 1. An imaging lens comprising: a first lens having positive refractive power, said first lens being formed in a shape so that a curvature radius of a surface thereof on an object side is positive; a second lens having negative refractive power, said second lens being formed in a shape so that a curvature radius of a surface thereof on the object side is negative and a curvature radius of a surface thereof on an image plane side is positive; and a third lens having positive refractive power, said third lens being formed in a shape so that a curvature radius of a surface thereof on the object side and a curvature radius of a surface thereof on the image plane side are both positive, arranged in this order from the object side to the image plane side, wherein said first lens is arranged so that the surface thereof on the image plane side is away from the surface of the second lens on the object side by a distance T1 on an optical axis, and said second lens is arranged so that the surface thereof on the image plane side is away from the surface of the third lens on the object side by a distance T2 on the optical axis so that the following conditional expression is satisfied: 1.6≦T1/T2<2.0 said first lens and said second lens have a composite focal length f12 so that the following conditional expression is satisfied: 4.0<f12/f<10.0where f is a focal length of a whole lens system. | ||
| 地址 | Nagano JP | ||