| 摘要 |
PROBLEM TO BE SOLVED: To provide an almost telecentric zoom lens whose view angle at a wide-angle end is >=60 deg. and whose zoom ratio is about 3. SOLUTION: This zoom lens 1 is three-group zoom lens consisting of negative, positive and positive groups. By positively giving refractive power to the 3rd group 4 and fixing the arrangement of paraxial refractive power so that the almost telecentric lens system may be obtained, a variable power effect is given between the 2nd group 3 and the 3rd group 4 so as to realize a high magnification zoom ratio, and the number of component lenses is reduced.
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