Invention Grant
- Patent Title: Zoom lens and imaging system using the same
- Patent Title (中): 变焦镜头和成像系统使用相同
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Application No.: US11901171Application Date: 2007-09-13
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Publication No.: US07684122B2Publication Date: 2010-03-23
- Inventor: Eiji Shirota
- Applicant: Eiji Shirota
- Applicant Address: JP Tokyo
- Assignee: Olympus Imaging Corp.
- Current Assignee: Olympus Imaging Corp.
- Current Assignee Address: JP Tokyo
- Agency: Kenyon & Kenyon LLP
- Priority: JP2006-260178 20060926
- Main IPC: G02B15/14
- IPC: G02B15/14 ; G02B17/00

Abstract:
The invention relates to a zoom lens that enables an optical path to be easily bent by a reflecting optical element, has a wide-angle design and high optical performance as represented by a high zoom ratio of about 3.4, is extremely slimmed down in the depth direction, and costs less. The zoom lens comprises a positive first lens group G1, a negative second lens group G2, a positive third lens group G3, a positive fourth lens group G4 and a negative fifth lens group G5. Upon zooming from the wide-angle end to the telephoto end, the first lens group G1 remains substantially fixed with respect to an image plane I, and at least the second G2 and the fourth lens group G4 move. The first lens group G1 includes a reflecting optical element for bending the optical path involved, and a portion of the first lens group G1 on an object side with respect to the reflecting surface has negative refracting power. The zoom lens satisfies condition (1) with respect to the focal length of the fifth lens group G5.
Public/Granted literature
- US20090002840A1 Zoom lens and imaging system using the same Public/Granted day:2009-01-01
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