Zoom optical system, optical apparatus and method for manufacturing the zoom optical system

A zoom optical system, consisting of, in order from an object on an optical axis:

• a preceding lens group having a negative refractive power;
• and a succeeding lens group having a positive refractive power, wherein
• the succeeding lens group essentially consists of two sub lens groups,
• one of the sub lens groups disposed close to the object is a focusing group, and the other one of the sub lens groups disposed close to an image is an image-side group,
• an aperture stop is disposed in the succeeding lens group,
• the preceding lens group essentially consists of a first lens group disposed closest to the object,
• upon zooming, a distance between the preceding lens group and the succeeding lens group changes,
• upon focusing from an infinity object to a short distance object, the focusing group moves toward the image on the optical axis, and
• the following conditional expressions are satisfied:
• 1.80<fF/fBaw
• FNow<3.40
• 1.00<(−f1)/fw<1.50
• 0.583≤STLw/TLw<0.70
• where
• fF:
• a focal length of the focusing group,
• fBaw:
• a focal length of the succeeding lens group in a wide angle end state,
• FNow:
• an f-number of the zoom optical system in the wide angle end state,
• TLw:
• an entire length of the zoom optical system in the wide angle end state,
• f1:
• a focal length of the first lens group,
• fw:
• a focal length of the zoom optical system in the wide angle end state, and
• STLw:
• a distance on the optical axis from a lens surface closest to the object in the zoom optical system to the aperture stop in the wide angle end state.