Zoom lens

Abstract

Abstract Translated from Japanese (57)【要約】 【目的】 ４群構成のズームレンズの小型化、並びに高 変化を図りつつ、レンズ鏡筒の簡素化及び近距離物体に 対して良好な光学性能で焦点合せを実行すること。 【構成】 物体側より順に負、正、Ｆ NO 絞り、正、負の 第１〜第４群で構成されるズームレンズで、広角端より 望遠端へのズーミングに際し、第１群と第２群の空気間 隔が増大し、第２群と第３群の空気間隔が増大し、第３ 群と第４群の空気間隔が減少する様に各群を移動させる と共に、前記Ｆ NO 絞りと３群の空気間隔は広角端より望 遠端の方が大きくなる様に移動させ、前記第３群を物体 側へ繰り出す事によって無限遠物体から近距離物体への フォーカシングを行う事。 (57) [Abstract] [Purpose] To achieve compactness and high change of a 4-group zoom lens while simplifying the lens barrel and performing focusing on a short-distance object with good optical performance. . [Constitution] A zoom lens composed of a negative, positive, FNO diaphragm, and positive and negative first to fourth groups in order from the object side. When zooming from the wide-angle end to the telephoto end, the first and second groups are used. The air gap between the second group and the third group increases, Each group is moved so that the air gap between the fourth group and the fourth group is reduced, and the air gap between the F NO diaphragm and the third group is moved so as to be larger at the telephoto end than at the wide-angle end. Focusing from an infinitely distant object to a short-distance object by feeding the object to the object side.

Inventors

• 👤 Yoshiaki Ito
• 👤 良紀 伊藤

Bibliographic Details