IR Detection

IR detection uses infrared radiation to verify the authenticity of banknotes. As the banknote passes through the counter, it is illuminated with infrared light and the sensor evaluates how its print absorbs, reflects or transmits the radiation. Genuine banknotes are printed with special inks that behave in a characteristic way in the infrared spectrum, whereas the ordinary printing inks used for counterfeits behave differently. Some parts of the print may be visible in infrared light, while others disappear completely. The measured image is compared with stored reference values for the given currency and denomination. The counter rejects a banknote that differs or alerts the operator. IR detection therefore increases the reliability of counterfeit detection together with other methods.