摘要 |
FIELD: engineering of devices for determining authenticity of banknote or security. ^ SUBSTANCE: device includes ultraviolet radiation source, connected to alternating voltage supply, block for protecting observation screen of ultraviolet radiation source with axis-symmetric chamber, form of pipe with three apertures, first aperture is connected to observation screen of ultraviolet radiation source, second aperture is optically connected to first aperture, gas tank is connected to third aperture, photo-receiver of reemitted optical radiation is connected via scale amplifier and upper frequency filter to demodulator, to which also a low frequency filter is connected through a limiting amplifier. cutting frequency of upper frequencies filter does not exceed minimum value of signal frequency at input of photo-receiver of reemitted optical energy radiation, and cutting frequency of low frequency filter is selected to be less than frequency of alternating voltage source. ^ EFFECT: increased interference resistance due to increased sensitive threshold. ^ 2 dwg |