发明名称 Retro-focus type wide angle objective lens
摘要 A retrofocus type wide angle objective lens comprising a negative lens group N and a positive lens group P having a diaphragm therein arranged in this order from the object side, said negative lens group N being constructed from a divergent front lens group F and a rear lens group R. When the lens is focused to a close object, only the rear lens group R located in the divergent light bundle from said front lens group F is moved in a different manner from that in which the other lens groups are moved in unison to effect good correction of aberrations in close photography.
申请公布号 US4025170(A) 申请公布日期 1977.05.24
申请号 US19750621595 申请日期 1975.10.10
申请人 CANON KABUSHIKI KAISHA 发明人 KAWAMURA, NAOTO
分类号 G02B13/04;(IPC1-7):G02B13/04 主分类号 G02B13/04
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