Patent ID: 11953664
Assignee: NIKON CORPORATION
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A zoom optical system comprising:
a first lens group having positive refractive power, a second lens group disposed on an image side of the first lens group and having negative refractive power, a third lens group disposed on an image side of the second lens group and having positive refractive power, a fourth lens group disposed on an image side of the third lens group and having negative refractive power, and a final lens group disposed on an image side of the fourth lens group and also disposed closest to an image,
wherein
a distance between the first lens group and the second lens group, a distance between the second lens group and the third lens group, and a distance between the third lens group and the fourth lens group change during zooming,
the first lens group is moved along an optical axis during zooming,
the second lens group comprises a vibration proof group capable of moving with a displacement component in a direction perpendicular to the optical axis and having negative refractive power,
a focusing lens group having negative refractive power is included,
the focusing lens group is moved along the optical axis during focusing,
the final lens group is disposed on an image side of the focusing lens group, and
the vibration proof group comprises, in order from an object, a negative lens, an air gap and a cemented lens of a negative lens and a positive lens.