Laser Box May Frustrate Forgers Physicists in London have accidentally invented a box with a laser that can detect microscopic patterns in paper. The device is being marketed as a detection tool for forged documents.
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Laser Box May Frustrate Forgers

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Laser Box May Frustrate Forgers

Laser Box May Frustrate Forgers

Laser Box May Frustrate Forgers

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Physicists in London have accidentally invented a box with a laser that can detect microscopic patterns in paper. The device is being marketed as a detection tool for forged documents.

RENEE MONTAGNE, host:

Forgery is a big problem that a scientist has now tackled. People counterfeit money, forge documents, duplicate credit cards. Companies spend millions trying to prevent this kind of fraud with fancy holograms, watermarks and magnetic strips. Now a scientist says you don't need all that. He claims you can just scan objects with a cheap laser to tell a forgery from the real thing. NPR's Nell Boyce reports.

NELL BOYCE reporting:

A physicist named Russell Cowburn is standing in a hotel room holding up two sheets of white office paper. They look identical, but he's invented a device that can tell them apart in a fraction of a second.

(Soundbite of machine)

BOYCE: It's a little metal box that holds a cheap laser that can see microscopic patterns on the paper's surface, a kind of fingerprint. Cowburn previously scanned one of the pieces of paper, but which one?

(Soundbite of machine)

BOYCE: He tries one sheet...

Mr. RUSSELL COWBURN (Physicist): And you see it's come up on the screen here, `item not recognized.'

(Soundbite of machine)

BOYCE: ...and then he tries the other.

Mr. COWBURN: And on the screen here, you see it's pinged up immediately, `sheet of paper one.' But what it's done is it's analyzed the surface of the paper, it's checked its database and it says, `Yep, I've seen that sequence of irregularities before. That was called sheet of paper one.'

BOYCE: If these pieces of paper had been contracts or security bonds, Cowburn says he could have easily told the real deal from a forgery. He discovered this technology by accident. He works on nanotechnology at Imperial College London, and over a year ago, he and his colleagues were trying to build a new kind of ID chip that would get read by a laser.

Mr. COWBURN: And one day the chip fell off the paper backing that it was attached to, and so the laser instead of bouncing off the chip bounced off the paper. And we noticed we got a signal and we thought, `Well, that's a bit strange. There should be nothing there because the chip is gone.'

BOYCE: The researchers soon realized that the microscopic fibers in paper formed tiny 3-D structures. These features reflect laser light in a unique speckled pattern.

Mr. COWBURN: If you or I look at the surface, it looks just like plain white paper, but to the microscopic eye of the scanner, these things look very different.

BOYCE: What they had stumbled across seemed pretty cool, but it wasn't clear if it had any practical value.

Mr. COWBURN: One of the things that worried us was that, well, maybe it works nicely in the laboratory, but once you get it out into the real world where people mistreat documents and put them in the back pockets and put them through the washing machine and things like that, maybe it's not tough enough to cope with real life.

BOYCE: But in the current issue of the journal Nature, Cowburn reports that it's surprisingly robust.

Mr. COWBURN: And I'm going to crumple it up into a very tight ball here.

(Soundbite of paper being crumpled)

BOYCE: Crumpling papers up, soaking them in water, baking them in an oven and spilling ink--every time the laser could still read the fingerprint.

(Soundbite of machine)

BOYCE: Cowburn now is working with a company to market the idea. He says scans from a billion unique items can fit into an ordinary hard drive. So computers could easily store billions of patterns for birth certificates, classified documents, even $20 bills, and Cowburn says it will work for more than just paper--leather coats, passport covers, boxes of pharmaceuticals--he sees some real advantages.

Mr. COWBURN: First of all, you don't have to do anything to your item that you want to protect. So all of the conventional security technology, special inks, holograms, all of these things, you've got to physically mark your item and that involves time and cost.

BOYCE: What's more, any would-be forger would face the daunting task of re-creating all the tiny complex patterns that appear on a surface.

Mr. COWBURN: And nobody knows how to do that. The reason nobody knows how to do it is we didn't do it in the first place. It was naturally occurring.

BOYCE: Other experts familiar with the technology also see the promise. Ravikanth Pappu works at a company called ThingMagic in Cambridge, Massachusetts.

Mr. RAVIKANTH PAPPU (ThingMagic): It's not hard to imagine Xerox machines, printers and things like that incorporating this method of identification, so each paper can be sort of identified with the data that's printed onto it.

BOYCE: Pappu thinks this kind of physical fingerprinting will grow in popularity, but he says one problem might be that each kind of object--cardboard box, leather coat--would need its own special scanner, and that could slow the technology's development and acceptance.

Nell Boyce, NPR News, Washington.

MONTAGNE: This is NPR News.

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