03 May 2007
A new anti-fraud technique brings biometric-style security to inanimate materials.
A laser-based method for trapping counterfeiters has won an international award and a €100,000 prize. Based on research at Imperial College, London, the technique uses Laser Surface Authentication (LSA) to "fingerprint" materials.
"This is a new approach that works without the need for anything to be modified or added to the item being tested. It just examines what's already intrinsically there," said Russell Cowburn of Imperial College and Ingenia Technology, a spin-off company set up to commercialize the technique. "It brings the principles used in biometric analysis to bear on inanimate objects."
The LSA method scans a material with a 635 nm, 1 mW diode laser, and records how the light is reflected back. Microscopic irregularities on the surface cause complex scattering of the laser beam, and the resulting speckle pattern forms the basis of a signature that is unique to any given item. These "fingerprints" can then be compared to establish authenticity.
"The scanning equipment is a portable set-up, comparable to a desktop scanner with attached PC," said Cowburn. The scanned area typically measures about 40 x 30 mm but can be much less for the most LSA-friendly surfaces, such as paper. Irregularities of less than a few hundred nanometers in size can be measured.
Not all materials are suitable for the new treatment. "Highly reflective surfaces don't work well," observes Cowburn. "If you can see your face in it, LSA may well not be suitable. And modifying the surface roughness to provide an LSA fingerprint would defeat the ease of use of the process."
The LSA technique is now being commercialized under the name ProteXXion by Ingenia Technology and Bayer Technology Services, who were jointly given the Hermes International Technology Award. The prize is given specifically for research innovations that have proved their worth in industrial practice.
Cowburn predicts a big future for LSA in combating organized smuggling rings, since it allows a unique, covert identifier to be assigned to an individual item without markers, chips or tags. "It's a low cost way to achieve a high level of security, usually a stronger level than more expensive methods can provide," he says. "There are no additional costs on top of the item's production, and the counterfeit protection doesn't interfere with the design or aesthetics. So everyone should be happy."