SYSTÈME OPTIQUE À PUISSANCE VARIABLE, DISPOSITIF OPTIQUE, ET PROCÉDÉ DE FABRICATION POUR UN SYSTÈME OPTIQUE À PUISSANCE VARIABLE

摘要

A zoom optical system (ZL) comprises a first negative lens group (G2) having a negative refractive power; and a second negative lens group (G4) disposed closer to an image than the first negative lens group (G2), wherein a distance between the first negative lens group (G2) and the second negative lens group (G4) changes during zooming, at least part of the first negative lens group (G2) is movable so as to have a displacement component in a direction perpendicular to an optical axis, at least part of the second negative lens group (G4) is movable along the optical axis during focusing, and the following conditional expression,is satisfied,where,fGa : a focal length of the first negative lens group (G2), andfGb : a focal length of the second negative lens group (G4).