Improvements relating to zoom lenses

Abstract

1,203,506. Zoom lenses. JOS. SCHNEIDER & CO. OPTISCHE WERKE. June 28, 1968 [June 30, 1967], No.30919/68. Heading G2J. A zoom lens has a front fixed positive group I, a movable negative group II, a movable negative group III, a fixed positive group IV and a fixed basic group V wherein:- (a) the focal length of group IV is less than 75% of that of group I and the focal length of group m is greater by at least 10% than the focal length of group II; (b) the focal length of group 1 is less than four times that of group V; (c) group II consists of negative meniscus L8 and a negative cemented component L 9 -L 11 (d) group III is a negative component formed of two lenses L 12 , L 13 of opposite power. (e) group IV consists of two positive lenses L 14 L 15 : and (f) group V consists of a negative cemented component formed of two lenses L 16 , L 17 , two positive elements L 18 , L 19 , a negative element L 70 , a positive lens L 21 , and a positive component formed of two lenses L 22 , L 23 . Optical dates are provided for three examples.

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Cited By (2)

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    EP-2390704-A1November 30, 2011Canon Kabushiki KaishaZoomobjektiv und Bildaufnahmevorrichtung damit
    US-8358470-B2January 22, 2013Canon Kabushiki KaishaZoom lens and image pickup apparatus including the same