Patent ID: 6424462
Filing Date: 2002-07-23
Classification: G02B,Y10T

Abstract:
A binocular, in which an interpupillary distance is adjusted by rotating each of a pair of eyepieces around a corresponding optical axis of optical axes of a pair of objective optical systems, said binocular comprising:a pair of rotating members that are rotatable for an interpupillary adjustment, each of said rotating members holding a corresponding eyepiece of said pair of eyepieces; and a mounting base including: a rotating member holding portion that holds said pair of rotating members; an objective optical systems holding portion that holds said pair of objective optical systems; and a connecting portion that is unitarily formed with said rotating member holding portion and said objective optical systems holding portion, connecting said rotating member holding portion and said objective optical systems holding portion such that said rotating member holding portion and said objective optical systems holding portion are parallel, said rotating member holding portion and said objective optical systems holding portion being a flat board-shaped member, wherein: first openings are formed in said rotating member holding portion, each of said rotating members being mounted in each of said first openings, second openings are formed in said objective optical systems holding portion, each of said objective optical systems being mounted in each of said second openings, said first openings and said second openings are formed such that: a first rotating member holding portion axis line, perpendicular to said rotating member holding portion, on which a geometric center of gravity of one first opening of said first openings lies, a first objective optical system holding portion axis line, perpendicular to said objective optical systems holding portion, on which a geometric center of gravity of one second opening of said second openings corresponding to said one first opening lies, and a first optical axis of one objective optical system of said objective optical systems which is mounted in said one second opening, are coincident; and a second rotating member holding portion axis line, perpendicular to said rotating member holding portion, on which a geometric center of gravity of another first opening of said first openings, a second objective optical system holding portion axis line, perpendicular to said objective optical systems holding portion, on which a geometric center of gravity of another second opening of said second openings corresponding to said another first opening, and a second optical axis of another objective optical system of said objective optical systems, which is mounted in said another second opening, are coincident, said optical axis of one eyepiece of said pair of eyepieces corresponds to said coincident first optical axis of said one objective optical system and said axis lines of said first rotating member holding portion and said first objective optical system holding portion, and said optical axis of another eyepiece of said pair of eyepieces corresponds to said coincident second optical axis of said another objective optical system and said axis lines of said second rotating member holding portion and said second objective optical system holding portion, and said one eyepiece and said another eyepiece are configured to rotate about said corresponding optical axes in an interlocking relationship.