VARIABLE POWER OPTICAL SYSTEM AND IMAGING DEVICE INCLUDING THE SAME

• Main Authors: FUJIKURA TAKASHI, SATORI TOSHIYUKI, YANAI TETSUYA, ZEN YUKI
• Format: Patent
• Language: English; Japanese
• Published: 29.11.2018
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PROBLEM TO BE SOLVED: To provide a variable power optical system with chromatic aberration satisfactorily corrected, and an imaging device including the same.SOLUTION: A variable power optical system has a first lens group G1 having positive refractive power, a second lens group G2 having negative refractive power, a third lens group G3 having positive refractive power, and at least one lens group. At the time of power varying, the second lens group and one lens group move, a second predetermined positive lens element satisfies conditional expressions (1), (2), a second predetermined negative lens element satisfies conditional expressions (3), (4), the second lens group has a first sub-lens group, a second sub-lens group, and a third sub-lens group, satisfying conditional expressions (5), (6). 0.520<(θg, F) G2p<0.610 (1) 0.680<(θC, t) G2p<0.900 (2) 0.520<(θg, F) G2n<0.560 (3) 0.750<(θC, t) G2n<0.900 (4)-0.25<fG21/fG22<0.90 (5)-0.70<fG21/fG23<0.40 (6).SELECTED DRAWING: Figure 1 【課題】色収差が良好に補正された変倍光学系及びそれを備えた撮像装置を提供する。【解決手段】正の屈折力を有する第１レンズ群Ｇ１と、負の屈折力を有する第２レンズ群Ｇ２と、正の屈折力を有する第３レンズ群Ｇ３と、少なくとも１つのレンズ群と、を有し、変倍時、第２レンズ群と１つのレンズ群が移動し、第２の所定の正レンズ素子は、条件式（１）、（２）を満足し、第２の所定の負レンズ素子は、条件式（３）、（４）を満足し、第２レンズ群は、第１副レンズ群と、第２副レンズ群と、第３副レンズ群と、を有し、条件式（５）、（６）、を満足する。０．５２０＜（θg,F）G2p＜０．６１０（１）０．６８０＜（θC,t）G2p＜０．９００（２）０．５２０＜（θg,F）G2n＜０．５６０（３）０．７５０＜（θC,t）G2n＜０．９００（４）−０．２５＜ｆG21／ｆG22＜０．９０（５）−０．７０＜ｆG21／ｆG23＜０．４０（６）【選択図】図１