| 发明名称 | Imaging lens | ||
| 摘要 | An imaging lens includes a first lens group having positive refractive power; a second lens group having positive refractive power; and a third lens group having negative refractive power, arranged in this order from an object side to an image plane side. The first lens group includes a first lens having positive refractive power, a second lens having negative refractive power, and a third lens having negative refractive power. The second lens group includes a fourth lens and a fifth lens. The third lens group includes a sixth lens and a seventh lens. The first to third lenses have specific Abbe's numbers. | ||
| 申请公布号 | US9541730(B2) | 申请公布日期 | 2017.01.10 |
| 申请号 | US201414572832 | 申请日期 | 2014.12.17 |
| 申请人 | Optical Logic Inc.;Kantatsu Co., Ltd. | 发明人 | Kubota Yoji;Kubota Kenichi;Hirano Hitoshi;Yonezawa Tomohiro |
| 分类号 | G02B9/12;G02B9/64;G02B13/00 | 主分类号 | G02B9/12 |
| 代理机构 | Kubotera & Associates, LLC | 代理人 | Kubotera & Associates, LLC |
| 主权项 | 1. An imaging lens comprising: a first lens group having positive refractive power; a second lens group having positive refractive power; and a third lens group having negative refractive power, arranged in this order from an object side to an image plane side, wherein said first lens group includes a first lens having positive refractive power, a second lens having negative refractive power, and a third lens having negative refractive power, said second lens group includes a fourth lens and a fifth lens, said third lens group includes a sixth lens and a seventh lens, and said sixth lens and said seventh lens have a composite focal length f67, said first lens has an Abbe's number νd1, said second lens has an Abbe's number νd2, and said third lens has an Abbe's number νd3 so that the following conditional expressions are satisfied: −1.7<f67/f<−0.5,40<νd1<75,20<νd2<35,20<νd3<35,where f is a focal length of a whole lens system. | ||
| 地址 | Nagano JP | ||