| 摘要 |
<p>The zoom lens substantially consists of a positive first lens group which is fixed while changing magnification, a negative second lens group which moves while changing magnification, a positive third lens group which moves while changing magnification, and a positive fourth lens group which is fixed while changing magnification in this order from the object side. The image formation magnification rates of the second lens group and the third lens group simultaneously pass a−1× point while changing magnification from the wide angle to the telephoto. The second lens group substantially consists of a negative second-a lens group and a positive second-b lens group which independently move while changing magnification in this order from the object side, and the third lens group substantially consists of a positive third-a lens group and a positive third-b lens group which independently move while changing magnification in this order from the object side.</p> |
