Detection system, used to recognize security printing e.g. on banknotes, or for cryptographic applications, involves using visible and non-visible phosphorescent images

摘要

A detector (3) assembly recognizes light reflected from media bearing fluorescent or phosphorescent media which are exposed to light sources (1, 2). The light sources emit light that is in ranges detectable by the human eye, and not detectable by the human eye. The assembly has internal light sources and polarized filters, and an external detector. The light sources are light emitting diodes, glass fibre -sheathed potassium cathode fluorescent tubes or laser diodes. The light detector is a CMOS chip, linear charged couple device (CCD) chip, or other CCD device.