发明名称 Zoom lens and image pickup apparatus including the same
摘要 A zoom lens includes a first lens unit having a positive refractive power which does not move for zooming; a second lens unit having a negative refractive power which moves during zooming; a third lens unit having a negative refractive power which moves during zooming; a fourth lens unit having a positive refractive power which moves during zooming; and a fifth lens unit having a positive refractive power which does not move for zooming. Air intervals (L2w and L2t) between the second lens unit and the third lens unit at a wide-angle end and at a telephoto end, respectively, an air interval (L3w) between the third lens unit and the fourth lens unit at the wide-angle end, a focal length (f1) of the first lens unit, and a combined focal length (f23w) of the second lens unit and the third lens unit at the wide-angle end are appropriately set.
申请公布号 US8743469(B2) 申请公布日期 2014.06.03
申请号 US201213446234 申请日期 2012.04.13
申请人 Canon Kabushiki Kaisha 发明人 Nakamura Tomoyuki;Takemoto Shoichi
分类号 G02B15/14 主分类号 G02B15/14
代理机构 代理人
主权项 1. A zoom lens, comprising, in order from an object side to an image side: a first lens unit having a positive refractive power which does not move for zooming; a second lens unit having a negative refractive power which moves during zooming; a third lens unit having a negative refractive power which moves during zooming; a fourth lens unit having a positive refractive power which moves during zooming; and a fifth lens unit having a positive refractive power which does not move for zooming, wherein the following conditions are satisfied: 5<L2w/L2t<50;0.6<L2w/L3w<2.5; and10<|f1/f23w|<25,where L2w and L2t represent air intervals between the second lens unit and the third lens unit at a wide-angle end and at a telephoto end, respectively, L3w represents an air interval between the third lens unit and the fourth lens unit at the wide-angle end, f1 represents a focal length of the first lens unit, and f23w represents a combined focal length of the second lens unit and the third lens unit at the wide-angle end.
地址 JP