VISIBILITY METER Russian patent published in 2002 - IPC

FIELD: optical instrumentation. SUBSTANCE: visibility meter has aperture diaphragm, achromatic and photometric wedges, first negative component, objective lens and eye-piece of telescope, electron-optical converter and second negative component being mounted between them. Visibility meter operates as follows: in initial position wedges overlap aperture diaphragm and visible image of object and background displaced with reference to optical axis of meter by value proportional to refraction angle of achromatic wedge and magnification of optical system is formed. In process of measurement wedges are moved relative to aperture diaphragm. In this case energy fluxes from object and background are divided into two fluxes and two images, main and additional, of same picture are formed on screen of electron-optical converter. Wedges are moved till visible contrast of main image of object reaches threshold value. This moment is considered reading moment to measure value of recognition of object. EFFECT: expanded spectral range of measurement of visibility parameters of object with simultaneous rise of precision and resolution of meter in infrared region of spectrum. 1 dwg