| 摘要 |
<p>Zoom lens (1) comprising, in order from object- to image-side, a first lens-group (2) having positive refractive power, a second lens-group (3) having negative refractive power, a third lens-group (4) having negative refractive power and a fourth lens-group (5) having positive refractive power. The second (3) and the third (4) lens-groups move towards the image-side during zooming from the wide-angle to the telephoto end and fulfil the inequalities m2T / m2W < 0, m3T / m3W < 0 and 0.8 < (m3T / m3W) / (m2T / m2W) < 3.0 where m2T (resp. m3T) denotes the magnification of the second (resp. third) lens-group at the telephoto end and m2W (resp. m3W) denotes the magnification of the second (resp. third) lens-group at the wide-angle end.</p> |
