发明名称 Zoom lens system
摘要 A zoom lens system having a negative first lens group and a positive second lens group in this order from the object, each of which is arranged to move for zooming; the first negative lens group including a first single positive lens element, a second single negative meniscus lens element having convex surface facing the object, a third single negative lens element and a fourth a positive single lens element having a convex surface facing the object, in this order from the object; the second positive lens group including a fifth a positive biconvex single lens element, a sixth positive single meniscus lens element having the convex surface facing the object, a seventh negative biconcave single lens element and an eighth positive single lens element, in this order from the object; and the following condition is satisfied:(n2+n3)/Z<1.32(1)Wherein ni designates the refractive index of the i-th lens; Z designates the zoom ratio of the zoom lens system.
申请公布号 US6078435(A) 申请公布日期 2000.06.20
申请号 US19980199813 申请日期 1998.11.25
申请人 ASAHI KOGAKU KOGYO KABUSHIKI KAISHA 发明人 YONEYAMA, SHUJI
分类号 G02B15/16;G02B15/177;(IPC1-7):G02B15/14 主分类号 G02B15/16
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