| 摘要 |
<p>A zoom lens comprising, in the order of an increasing distance from an object; a fixed first lens group (1) having a positive refractive power; a second lens group (2) containing an aspherical surface, having a negative refractive power and being in charge of a variable power action by being moved; a fixed third lens group (3) containing an aspherical surface and having a positive refractive power; and a fourth lens group (4) containing an aspherical surface, having a positive refractive power and moving while following up a moving object point; wherein the surface on the image plane side of a lens closest to the image plane in the third lens group (3) has a concave plane having a strong refractive power with respect to the image plane and a relation, 2.0∫L/CL1∫2.3, is satisfied when an effective aperture of a lens (1a) closest to the object in the first group is CL1 and a distance from the lens (1a) to the image plane is L, whereby a high-magnification, compact and wide-angle zoom lens having its aberration adequately corrected can be obtained with a simple configuration.</p> |
