Patent ID: 8339713
Filing Date: 2012-12-25
Classification: G02B,Y10T

Abstract:
1. A zoom optical system comprising, in order from an object side: a first lens group having positive refractive power; a second lens group having negative refractive power; and a rear lens group having positive refractive power; the rear lens group including at least a third lens group that is disposed to the most object side and has positive refractive power, the third lens group including at least four positive lenses and at least one negative lens, at least a portion of a lens group disposed to an image side of the first lens group being movable as a vibration reduction lens group in a direction including a component perpendicular to an optical axis, and the following conditional expression being satisfied: where Lf denotes a total length of the third lens group, and Lr denotes a total length of the rear lens group in a wide-angle end state.