University Of Toronto Technology Could Foil Fraud With Laser-sensitive Dyes

"This technology will give security or customs authorities the confidence that documents are not fake," says U of T chemistry professor Eugenia Kumacheva, who holds the Canada Research Chair in Advanced Polymer Materials. "It gives a very high level of data encryption and is relatively cheap to produce."

A thin film of polymer material is produced from tiny three-layer capsules comprising three different dyes, Kumacheva explains. Each layer is sensitive to light at a particular wavelength – ultraviolet, visible or infrared. Using high-intensity irradiation, Kumacheva uses differing wavelengths to encrypt several different patterns onto a security document. To the naked eye, the identification document (a passport or smart card, for example) might reveal a photograph, but under other detection devices could reveal signatures or fingerprints.

The technology could offer a speedy alternative to waiting in long lineups at security checkpoints or government offices, says Kumacheva, who has secured a patent on the technology. A paper on the technology, which she says could be available within five years, was presented at a recent Particles 2003 meeting in Toronto.