Title:
ZOOM LENS AND OPTICAL EQUIPMENT USING THE SAME
Document Type and Number:
Japanese Patent JP3492336
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain a zoom lens constituted of a small number of lenses, made compact and having excellent optical performance, and to obtain optical equipment using the zoom lens.
SOLUTION: The zoom lens has a 1st lens group having negative refractive power, a 2nd lens group having positive refractive power, a 3rd lens group having positive refractive power, and a 4th lens group having positive refractive power in this order from an object side, and performs zooming by moving at least the 2nd and the 3rd lens groups to the object side so that space between the 1st and the 2nd lens groups may be smaller, space between the 2nd and the 3rd lens groups may be smaller and space between the 3rd and the 4th lens groups may be larger at a telephoto end than at a wide angle end. In the 1st lens group, a negative lens is positioned nearest to the object side, and the 2nd lens group has two or more positive lenses and one or more aspherical surfaces.
Inventors:
Yoshinori Ito
Application Number:
JP2001200584A
Publication Date:
February 03, 2004
Filing Date:
July 02, 2001
Export Citation:
Assignee:
Canon Inc
International Classes:
G02B7/10; G02B13/18; G02B15/20; (IPC1-7): G02B15/20; G02B13/18
Domestic Patent References:
| JP6031110A |
Attorney, Agent or Firm:
Yukio Takanashi
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