Microscopic "fingerprints" formed by surface imperfections on nearly all documents and plastic cards might be used as a cheaper method to combat fraud.
Researchers at Imperial College London and Durham University say the inherent identity code is virtually impossible to modify and can be easily read using a low-cost portable laser scanner.
The researchers believe the technology could also prove valuable in the fight against terrorism by making it harder to fake passports, ID cards and documents such as birth certificates.
All non-reflective surfaces have naturally occurring roughness that is a source of physical randomness. And that, say scientists, could replace current, more costly identification measures, such as holograms or security inks.
"This is a system so secure that not even the inventors would be able to crack it since there is no known manufacturing process for copying surface imperfections at the necessary level of precision," said lead author Russell Cowburn, professor of Nanotechnology at Imperial College London.
Cowburn and his colleagues are now working with their spin-off company Ingenia Technology to take the idea to market.
The study appears in the current issue of the journal Nature.
Copyright 2005 by United Press International
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