发明名称 ZOOM LENS SYSTEM AND ELECTRONIC IMAGING APPARATUS
摘要 A zoom lens system includes a negative first lens group, a positive second lens group and a positive third lens group, in that order from the object side, wherein upon zooming from the short to long focal length extremities, the distance between the first and second lens groups decreases, and the distance between the second and third lens groups increases. The first lens group includes a negative lens element and a positive lens element; and the second lens group includes a cemented lens formed from a positive lens element and a negative lens element, and a negative lens element, in that order from the object side. The following conditions (1) and (2) are satisfied: 1.8<ft/f2<2.4&emsp;&emsp;(1), &minus;1.5<f1/f2<&minus;1.2&emsp;&emsp;(2), wherein ft designates the focal length of the entire the zoom lens system at the long focal length extremity, and f1 and f2 designate the focal lengths of the first and second lens groups, respectively.
申请公布号 US2012069451(A1) 申请公布日期 2012.03.22
申请号 US201113198042 申请日期 2011.08.04
申请人 NAKAMURA TOSHIKI;HOYA CORPORATION 发明人 NAKAMURA TOSHIKI
分类号 G02B15/14 主分类号 G02B15/14
代理机构 代理人
主权项
地址
您可能感兴趣的专利