发明名称 |
WIDE ANGLE LENS AND IMAGING DEVICE |
摘要 |
A wide angle lens whose field angle exceeds 180 degrees includes a front group, a diaphragm, and a rear group arranged in this order from an object side toward an image side. The front group includes a first lens (negative meniscus lens) whose convex surface faces the object side, a second lens (negative lens), and a third lens (positive lens) that are arranged in this order from the object side toward the image side. The rear group includes a fourth lens (positive lens), a fifth lens (negative lens), and a sixth lens (positive lens) that are arranged in this order from a diaphragm side toward the image side. Accordingly, an imaging system including six separate lenses is formed. The third lens is made of a material having an Abbe number ?dL3 satisfying ?dL3<21. The fifth lens is made of a material having an Abbe number vdL5 satisfying ?dL5<21. |
申请公布号 |
WO2010113669(A1) |
申请公布日期 |
2010.10.07 |
申请号 |
WO2010JP54742 |
申请日期 |
2010.03.15 |
申请人 |
RICOH COMPANY, LTD.;YOSHIDA, HAYATO;MONIWA, NAOKI;ABE, ISSEI |
发明人 |
YOSHIDA, HAYATO;MONIWA, NAOKI;ABE, ISSEI |
分类号 |
G02B13/00;G02B13/18 |
主分类号 |
G02B13/00 |
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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