METHOD OF SPECTRAL FILTRATION OF OPTICAL SIGNALS AND ACTIVE QUANTUM FILTER FOR ITS IMPLEMENTATION Russian patent published in 1999 - IPC

FIELD: optoelectronics, laser equipment. SUBSTANCE: invention can be used in laser location and in high- precision physical measurement equipment to extract, detect and amplify extremely weak optical signals against background of heavy wide-band optical strobing. Magnetic field which intensity value is changed till maximum amplitude of test signal with specified parameters passed through excited laser medium is formed in excited laser medium. Active quantum filter meant for implementation of method plays simultaneously functions of quantum amplification and filtration of optical signals in narrow spectral band. EFFECT: formation and stabilization of spectral amplification ( reception ) band of optical signals optimal by width and form, increase of spectral contrast of amplification band, increase of sensitivity of reception of optical signals approaching to quantum limit. 2 cl, 6 dwg