| 摘要 |
PURPOSE: A zoom lens is provided to prevent the generation of spherical aberration by decentralizing a positive refractive power by arranging at least three positive lenses in a first lens group. CONSTITUTION: A first lens group(G1) has a positive refractive power. A second lens group(G2) has a negative refractive power. A following group(GB) has a positive refractive power. The first optic group comprises at least one negative lens and at least three positive lenses. The second lens group comprises a front group(G2-1) which has a negative refractive power and a rear group(G2-2) which has a positive refractive power. |
