FLARE PROTECTION LENS HOOD FOR OPTICAL INSTRUMENTS Russian patent published in 1997 - IPC

FIELD: optical instruments which protect against flare. SUBSTANCE: device has housing and aperture set, in which each aperture is designed as side surface of cone frustum which generatrix is at angle of 80-110 degrees to extreme flare angle for corresponding aperture, which light edge is located in sight of optical instrument. Light edge of preceding aperture, if counting starts from input aperture of lens hood, is located in straight line piece which is limited with light edge of next aperture and point of intersection of sight border of instrument and straight line which connects point in which next aperture is mounted to hood housing, and point in which flare beams enter. EFFECT: decreased size. 1 dwg