Compact wide-angle zoom lens
AssigneeAsahi Kogaku Kogyo Kabushiki Kaisha
InventorTakayuki Itoh
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AssigneeAsahi Kogaku Kogyo Kabushiki Kaisha
InventorTakayuki Itoh
Estimating the term…
A compact wide-angle zoom lens comprising, in order from the object side, a variator that consists of a first lens component having a negative focal length and a second lens component having a positive focal length, and a single-element fixed third lens component (relay lens system) that is positioned subsequent to the variator for increasing its focal length. The first lens component has a negative-positive lens unit arrangement. The second lens component has a positive-negative-positive lens unit arrangement. The first and second lens component are mechanically moved so as to provide a variable focal length and maintain a constant focal position. The following conditions are satisfied: ##EQU1## where f.sub.1 : the focal length of the first lens component; f.sub.2 : the focal length of the second lens component; f.sub.L : the focal length of the overall system for the narrow-angle position; and m.sub.3 : the lateral magnification of the third lens component.
A compact wide-angle zoom lens having a plurality of lens components, at least some of which are movable between a wide-angle position and a narrow-angle position, said zoom lens being composed, in order from the object side, of a variator that consists of a first lens component having a negative focal length and a second lens component having a positive focal length, and a fixed third lens component that is positioned subsequent to the variator for increasing its focal length, said first lens component having a negative-positive lens unit arrangement, said second lens component having a positive-negative-positive lens unit arrangement, and said first and second lens components being mechanically moved so as to provide a variable focal length and maintain a constant focal position, said third lens component being composed of only one negative lens element, wherein the following conditions are satisfied:
Dependencies are inferred from the claim text.