Patent ID: 6314246
Filing Date: 2001-11-06
Classification: C03C,G03B

Abstract:
A viewfinder optical system of a single-lens reflex camera having a photographic optical system and an image plane positioned on an optical axis of the photographic optical system, wherein the camera photographs an object image formed on the image plane through the photographic optical system, said viewfinder optical system comprising:a first optical member positioned between the photographic optical system and the image plane, said first optical member bending the optical axis of the photographic optical system to define a viewfinder optical axis of said viewfinder optical system;a second optical member which bends said viewfinder optical axis at least once to make said viewfinder optical axis extend parallel to the optical axis of the photographic optical system;a third optical member, having substantially no optical power, positioned on the viewfinder optical axis which extends parallel to the optical axis of the photographic optical system, said third optical member transmitting, along the viewfinder optical axis, substantially all light incident onto said third optical member and being made of a transparent material having a refractive index higher than the refractive index of air; andan eyepiece positioned behind said third optical member on the viewfinder optical axis extending parallel to the optical axis of the photographic optical system.