Title:
OBSERVATION DEVICE
Document Type and Number:
Japanese Patent JP2021018283
Kind Code:
A
Abstract:
To provide an observation device that has a high viewing angle and can be reduced in size.SOLUTION: An observation device has a display element including an image display surface, and an eyepiece optical system for observing the image display surface. The eyepiece optical system consists of one negative lens having a negative refractive force and two positive lenses having a positive refractive force. The observation device appropriately sets the focal distance of the entire system of the eyepiece optical system, the focal distance of the negative lens, the refractive index on a d line of the negative lens, the half diagonal length of the image display surface, the distance from a surface of the eyepiece optical system closest to the display element to a pupil position of the eyepiece optical system facing the display element, and the distance from a surface of the eyepiece optical system closest to an eye point to the eye point.SELECTED DRAWING: Figure 1
Inventors:
OKADA TAKASHI
Application Number:
JP2019132486A
Publication Date:
February 15, 2021
Filing Date:
July 18, 2019
Export Citation:
Assignee:
CANON KK
International Classes:
G02B25/00; G02B13/18; G02B27/02
Attorney, Agent or Firm:
Ryosuke Fujimoto
Atsushi Mizumoto
Hirayama Tomoya
Atsushi Mizumoto
Hirayama Tomoya