| 摘要 |
<p>[Problem] To shorten overall length and to obtain a wide field of view and a high magnification ratio in a zoom lens. [Solution] The zoom lens is configured by disposing, in order from the object side: a first lens group (G1) having a positive refractive power; a second lens group (G2) having a negative refractive power; a third lens group (G3) having a positive refractive power; and a fourth lens group (G4) having a negative refractive power. Additionally, the configuration is such that when changing the magnification from the wide end to the tele end side, all the lens groups move along the optical axis (Z) in a manner so that the spacing between the first lens group (G1) and the second lens group (G2) progressively widens, the spacing between the second lens group (G2) and the third lens group (G3) progressively narrows, and the spacing between the third lens group (G3) and the fourth lens group (G4) progressively widens. Also, when the focal distance of the overall system at the wide end is fw, the focal distance of the second lens group is f2, and the focal distance of the fourth lens group is f4, the following conditional expressions are satisfied: -2.0 < fw/f2 < -0.8 ...(1); and -1.0 < fw/f4 < -0.2 ...(2).</p> |
