| 摘要 |
A wide-angle zoom lens system includes a first lens group having a positive refractive power and a second lens group having a negative refractive power and spaced from the first lens group at a first distance, the first distance being variable during zooming. The first lens group includes a first lens having a positive refractive power and a convex surface toward an object, a second lens having a negative refractive power and concave surfaces, a third lens having a positive refractive power and convex surfaces, a fourth lens having a negative refractive power and convex surfaces, a fifth lens having a negative refractive power and a concave surface toward the object, and a sixth lens having a positive refractive power and one of convex and meniscus surfaces. The second lens group includes a seventh lens having a positive refractive power and a concave surface toward the object and at least one element of a negative refractive power lens. The zoom lens system having the following characteristics:0.5<f1/fw<0.820.42<|f2/fw|<0.82, f2<01.3<m2w<1.9where f1 is a focal length of the first lens group, f2 is a focal length of the second lens group, fw is a focal length of the zoom lens system at a wide angle position, and m2w is an image formation magnification at a wide angle position.
|
