| 发明名称 | Zoom lens and image pickup apparatus including the same | ||
| 摘要 | A zoom lens including, in order from an object side, positive, negative, positive, positive, and positive lens units, or positive, negative, positive, positive, positive, and positive lens units. 1.5<L2fm/L2W<500; −30<f3/f2<−3; and −15<f1/f23W<−8 are satisfied, where fm=fw×(Z)1/2, fw represents a focal length of the entire system at a wide angle end, Z represents a zoom ratio, L2W represents an interval between a second and third lens units at the wide angle end, L2fm represents an interval between the second and third lens units at a zoom position at which an offaxial principal ray having a largest image height is highest farthest from an optical axis on a lens surface disposed on the most object side in the first lens unit in a zoom range from the wide angle end to the focal length fm, f1, f2 and f3 respectively represent focal lengths of the first, second, and third lens units, and f23W represents a combined focal length of the second and third lens unit at the wide angle end. | ||
| 申请公布号 | US9400374(B2) | 申请公布日期 | 2016.07.26 |
| 申请号 | US201414161865 | 申请日期 | 2014.01.23 |
| 申请人 | CANON KABUSHIKI KAISHA | 发明人 | Yoshimi Takahiro;Shimomura Kazuya |
| 分类号 | G02B15/14;G02B15/173;G02B15/167 | 主分类号 | G02B15/14 |
| 代理机构 | Carter, DeLuca, Farrell & Schmidt, LLP | 代理人 | Carter, DeLuca, Farrell & Schmidt, LLP |
| 主权项 | 1. A zoom lens, comprising, in order from an object side to an image side: a first lens unit having a positive refractive power, which does not move for zooming; a second lens unit having a negative refractive power, which moves during zooming; a third lens unit having a positive refractive power, which moves during zooming; at least one lens unit having a positive refractive power, which moves during zooming; and a last lens unit having a positive refractive power, which does not move for zooming, wherein, when a focal length fm at an intermediate zoom position is expressed by fm=fw×(Z)1/2 where fw represents a focal length of the zoom lens at a wide angle end, and Z represents a zoom ratio, the following conditional expressions are satisfied: 1.5<L2fm/L2W<500;−30<f3/f2<−3; and−15<f1/f23W<−8,where L2W represents an interval between the second lens unit and the third lens unit at the wide angle end, L2fm represents an interval between the second lens unit and the third lens unit at a zoom position at which an offaxial principal ray having a largest image height is farthest from an optical axis on a lens surface disposed on a most object side in the first lens unit in a zoom range from the wide angle end to the focal length fm, f1 represents a focal length of the first lens unit, f2 represents a focal length of the second lens unit, f3 represents a focal length of the third lens unit, and f23W represents a combined focal length of the second lens unit and the third lens unit at the wide angle end. | ||
| 地址 | Tokyo JP | ||