Patent ID: 6292629
Filing Date: 2001-09-18
Classification: G03B

Abstract:
An indicator provided within a view finder for a single lens reflex camera, comprising:a pentagonal prism having a roof reflection surface, said roof reflection surface having two reflection surfaces normal to each other, wherein said roof reflection surface reflects light emitted from a focusing plate which is located at a position optically equivalent to an imaging plane of a photographic lens of said single lens reflex camera, and a third reflection surface which reflects said light reflected by said roof reflection surface toward an eyepiece, wherein said third reflection surface comprises a semitransparent surface;an auxiliary prism adhered to said semitransparent surface; an indicator plate comprising an information mask which lies in a plane substantially perpendicular to the optical axis of said eyepiece; and an illumination light source which emits light through said information mask of said indicator plate, in that order from the opposite side of the auxiliary prism with respect to the third reflection surface thereof; anda diopter correcting lens, adapted to make the position of said indicator plate optically equivalent to the position of said focusing plate, provided between the auxiliary prism and the indicator plate.