发明名称 |
ZOOM LENS, IMAGING APPARATUS, AND METHOD FOR MANUFACTURING ZOOM LENS |
摘要 |
A zoom lens including, from an object: a front group having negative power; and a rear group having positive power, the rear group including, from the object, a positive lens, a negative lens having a concave surface facing the object, a cemented positive lens constructed by a negative lens and a positive lens, and a cemented lens constructed by a positive lens and a negative lens, the rear group further including a focusing group disposed to the object side of the positive lens La for focusing from infinity to a close object by moving from the object side to an image side, a distance between the front group and the rear group being varied thereby zooming from a wide-angle end state to a telephoto end state, and given condition being satisfied, thereby providing a downsized zoom lens having wide angle of view and excellent optical performance with fewer lenses. |
申请公布号 |
US2014355129(A1) |
申请公布日期 |
2014.12.04 |
申请号 |
US201414462103 |
申请日期 |
2014.08.18 |
申请人 |
Nikon Corporation |
发明人 |
Sato Haruo;Tanaka Issei |
分类号 |
G02B13/04;G03B19/20;G02B1/11 |
主分类号 |
G02B13/04 |
代理机构 |
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代理人 |
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主权项 |
1. A zoom lens comprising, in order from an object side:
a front lens group having negative refractive power; and a rear lens group having positive refractive power, the rear lens group including, in order from the object side, a positive lens La, a negative lens Lb having a concave surface facing the object side, a cemented positive lens Lc constructed by a negative lens cemented with a positive lens, and a cemented lens Ld constructed by a positive lens cemented with a negative lens, the rear lens group further including a focusing lens group Gf having positive refractive power, disposed to the object side of the positive lens La for carrying out focusing from an infinitely distant object to a close object by moving from the object side to an image side, a distance between the front lens group and the rear lens group being varied thereby carrying out zooming from a wide-angle end state to a telephoto end state, the following conditional expression being satisfied:
0.000<Fw/(−Fb)<1.000 where Fw denotes a focal length of the zoom lens in a wide-angle end state upon focusing on an infinitely distant object, and Fb denotes a focal length of the negative lens Lb in the rear lens group. |
地址 |
Tokyo JP |