DEVICE FOR DETECTION OF SOURCES OF COHERENT RADIATION Russian patent published in 1994 - IPC

FIELD: nonlinear optics. SUBSTANCE: device for detection of sources of coherent radiation has first light filter, which transmission equals 1 with frequencies less than first frequency of cut-off and equals 0 with frequencies greater than first frequency of cut-off, nonlinear crystal, second light filter which transmission equals 1 with frequencies greater than second frequency of cut-off and equals 0 with frequencies less than second frequency of cut-off. Second cut-off frequency is greater than first one and relation of second cut-off frequency to first one is less than two (usually it is chosen between 1.2 and 1.7). Device also includes photodetector. Device is incorporated in light impenetrable case. It allows sources of coherent optical radiation with low intensity under conditions of heavy noises, for instance in sun light, to be recorded. EFFECT: improved operational characteristics. 1 dwg