| 摘要 |
A telephoto lens system includes a positive first lens group, a negative second lens group and a positive third lens group. Upon focusing, the second lens group moves toward the image, and the telephoto lens system satisfies the following conditions: 1.35<f/f1<1.80 . . . (1); 1.30<|f/f2|<1.85 . . . (2); 0.48<f/f3<0.75 . . . (3) and 0.10<|L2/f2|<0.22 . . . (4); wherein f designates the focal length of the entire telephoto lens system; f1 designates the focal length of the first lens group; f2 designates the focal length of the second lens group; f3 designates the focal length of the third lens group; and L2 designates the distance between the second lens group and the third lens group when an object at an infinite photographing distance is in an in-focus state.
|
