Seaborough’s LUMICRYPT™ Engineers Unique Luminescent Fingerprints
Security printing has always borrowed optical phenomena from physics and chemistry, and few are as useful as luminescence.
A luminescent ‘phosphor’ is an inorganic material that can soak up light of one colour, often ultraviolet (UV), and then
re-emit it at another, usually visible, colour. In a banknote or ID document, that behaviour becomes a controlled ‘signal’. Under normal lighting, the ink may look unremarkable, but under a defined UV lamp it produces a distinctive glow that is easy to spot and, importantly, can be measured.
At a simple level, this is why UV features remain popular for first-line checks. But the real power is that phosphors can be engineered to emit very specific spectra, making a ‘fingerprint’ of the light they give off, and those fingerprints can be read with compact instruments.
Subscriber content
Read the full article
Full access to Holography & Optical Technology News articles, newsletters and archives.