By Peter Weiss
A credit card or sheet of paper might look smooth, but under a microscope, these surfaces teem with ridges, pits, and other irregularities. Now, researchers in England have devised a way to translate those random artifacts of manufacturing into unique identification codes. Such codes are difficult, if not impossible, to forge, the developers claim.
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Russell P. Cowburn of Imperial College London and his colleagues describe their authentication scheme in the July 28 Nature. A London-based start-up company, to which some of the researchers have financial ties, is already manufacturing a laser-based coding system that applies the new strategy.