Fingerprint scanning for documents

Imperial College London has developed a low-cost scanning system that can see the individual fibres that many materials consist of and record these images as unique fingerprints.

The LSA (Laser Surface Authentication) system can see the imperfections that occur in paper, ceramics and even metals. With these imper-fections almost impossible to accurately replicate, they provide an ideal opportunity to add another layer of security to sensitive document such as passports, but could also help in the fight against pirate copies of CD’s and DVD’s that are flooding the UK market.

Russell Cowburn, Professor of Nanotechnology in the Depart-ment of Physics, Imperial College London, stated, “Our findings open the way to a new and much simpler approach to authentication and tracking. 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 imper-fections at the necessary level of precision.”

The system uses an optical phenomenon called ‘laser speckle.’ A finely tuned laser is able to scan the surface of an object and then record the intensity of the light that is reflected back. With tests on a wide variety of materials from plastic cards to coated paper stock, there was a clear recognition between the samples even after they had been subjected to abuse including submersion in water and even scorching.

Professor Cowburn continued, “The beauty of this system is that there is no need to modify the item being protected in any way with tags, chips or inks, it’s as if documents and packaging have their own unique DNA. This makes protection covert, low-cost, simple to integrate into the manufacturing process and immune to attacks against the security feature itself.”