What is it?
Fluorescence is a light emitting effect where the outgoing light has a lower frequency than the incoming light.
How do you detect it?
Authentication of security features using fluorescence is in general done by observing the light emission and color shifting effect.
How does it work?
Fluorescence is usually achieved using special molecules, atoms or nanostructures which emit photons when their constituting atoms change from higher to lower energy states after excitation. The fluorescent elements are often mixed into inks so that they can be printed on documents and packaging. They can also be integrated into plastic.
In general, fluorescence for brand protection is an outdated technology. It may still be appropriate in extremely specific scenarios, when the supply chain involves very few manufacturers or printers. Moreover, it is limited solely to internal use, since it usually requires specific UV or IR detectors (unless a low-security UV lamp is used). Finally, it creates additional burdens on the brand owner for the supply and distribution of the fluorescent substance and of the detection hardware. In practice, whenever fluorescent markers are printed, it would be more effective to replace them with a Cryptoglyph®, which is less expensive on the manufacturing side, more secure and easier to deploy. If the fluorescent substance is used for molded plastic products, then the AlpVision Fingerprint® approach will also be more appropriate and for the same reasons: it is simpler, more secure, and has lower manufacturing costs.
Field of application
Banknotes, passports, metal and plastic caps, pharmaceutical vials and official documents.