| 摘要 |
PURPOSE:To provide a high variable power and to compensate aberrations well, by moving the third lens group and the following lens group to focus the zoom lens which consists of four lens groups and is suitable for a video camera or the like and is compact and has a high variable power. CONSTITUTION:The zoom lens has the first lens group which has a positive refracting power, the second lens group which has a negative refracting power, and the third and the fourth lens group which have a positive or negative refracting power, and these lens groups are arranged in order from the object side. Intervals of spaces of respective lens groups of the first... the third lens groups are changed to perform zooming. Each of the first and the second lens groups is constituted with two lenses. The third lens group and the following lens group are moved to perform focusing. Since lenses are so constituted in this convention that aberrations are compensated well among lens groups moved by varying of magnifications, aberrations are compensated well though each of the first and the second lens group is constituted with two lenses. |
