公开(公告)号：US20180329200A1

公开(公告)日：2018-11-15

申请号：US16029492

申请日：2018-07-06

Applicant: NIKON CORPORATION

Inventor： Taku MATSUO ,  Motohisa MOURI ,  Yukio KUBOTA ,  Takuya SATO

IPC: G02B25/00

CPC classification number: G02B25/001 ,  G02B13/18

Abstract: Provided is an eyepiece optical system including at least three lenses disposed in order from an observation object (Ob) along an optical axis. A final lens disposed closest to an eye point (EP) (corresponds to the third lens (L3) in FIG. 1) is fixed when adjusting the diopter, and the following conditional expressions (1) and (2) are satisfied: 2.2