发明名称 |
Variable lens system with positive and negative groups of lenses |
摘要 |
The positive first group of lenses (11) and the negative second group of lenses (12) are variably spaced apart for altering the focal distance and which are positioned in a series from the object side. The first lens group has a negative first lens element. A plastic second lens element has at least one aspherical surface and a positive third lens element.
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申请公布号 |
DE19918338(A1) |
申请公布日期 |
1999.10.28 |
申请号 |
DE19991018338 |
申请日期 |
1999.04.22 |
申请人 |
ASAHI KOGAKU KOGYO K.K., TOKIO/TOKYO |
发明人 |
ENOMOTO, TAKASHI |
分类号 |
G02B13/18;G02B15/16;(IPC1-7):G02B15/16 |
主分类号 |
G02B13/18 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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