| 摘要 |
Providing a telephoto-type of zoom lens having a high zoom ratio being compact with high optical performance. The zoom includes, in order from an object along an optical axis, a first lens group (G1) having positive refractive power, a second lens group (G2) having negative refractive power, a third lens group (G3) having positive refractive power, and a fourth lens group (G4) being disposed on the most image side. The fourth lens group (G4) has positive refractive power and includes, in order from the object, a front group (G4a) and a rear group (G4b) having positive refractive power and a focal length (fNb). Focusing on an object is carried out by moving the rear group (G4b) along the optical axis, and an inequality involving fNb is satisfied.
The third lens group (G3) has an aperture stop on its object side and a rear part moving perpendicularly to the optical axis to correct image shake. |
