Detection Device Uses Printed Liquid Crystal Lasers to Fight Fraud

A detection device which uses printed lasers to identify counterfeit goods has been developed by electrical engineers at the UK's University of Cambridge. The anti-fraud detector works by exploiting an existing method for printing liquid crystal lasers with inkjet printers, which gives the user precise control over the laser's pattern and color combination. The detector then takes advantage of this by shining a second, laser pulse on to the printed one. It then reads the wavelength of the light emission from the printed laser through dedicated software, and reproduces that reading as a pattern on a spectrograph. The result is that each printed laser can be designed to give out its own, unique optical signature. Since lasers can be printed on to all sorts of surfaces - such as plastic, paper, metal, and glass - the technique could be used to authenticate a wide range of products.