| 摘要 |
<p>A high power zoom lens system includes, in order from the object side: a first lens group having a positive refractive power and remaining stationary during zooming; a second lens group having a negative refractive power and moving during zooming; a third lens group and a fourth lens group having a positive refractive power and being movable relative to each other to correct image plane variation accompanied by zooming; and a fifth lens group having a positive refractive power and including an aperture diaphragm, the fifth lens group being used for forming an image. The second lens group and a composite lens group formed by combining the third lens group and the fourth lens group pass simultaneously through -1 × magnification points of the groups during zooming from a wide-angle end to a telephoto end. The fourth lens group has at least one aspheric surface.</p> |
