| 摘要 |
An intermediate telephoto lens system includes a first lens group 1, and a second lens group 2. The first lens group 1 includes a first lens element, a second lens element, a third lens element, an aperture stop, cemented lens elements constituted by a fourth lens element and a fifth lens element, and a sixth lens element. The second lens group 2 includes a seventh lens element, and an eighth lens element. Upon focusing, only the first lens group 1 moves along the optical axis. The intermediate telephoto lens system satisfies the following condition: (&ngr;'1-1 +&ngr;'1-2)/2>102 . . . (1); &ngr;'1-1: the dispersion ratio of the first lens element; &ngr;'1-2 the dispersion ratio of the second lens element; &ngr;'=(nd-1)/(ng-nF); nd: the refractive index of the d-line for each lens element; ng: the refractive index of the g-line for each lens element; nF: the refractive index of the F-line for each lens element.
|
