Next time you go to the bank, don't be surprised to see somebody waving a mouse at your holiday money.
Researchers at the University of Lleida say the sensor of some optical mice can be used to easily and cheaply detect counterfeit euros, and have developed a prototype based on one.
The coin is placed in a positioning device and is rotated to detect forgeries. The sensor captures images from the common face of the two-euro coins - all have a map of Europe engraved on one side, and a country-specific design on the other.
The images are then compared with reference images obtained from genuine coins, using an algorithm also developed by the Catalan team.
"The advantage of these sensors is their small size, low cost and the angle of vision reduced to such an extent that the raised image of coins can easily be captured", Marcel Tresanchez, one of the authors of the study, points out.
Not just any optical mouse sensor will work, as images must be captured in real time, with a minimum resolution of 15x15 pixels. It's also better to use an LED- or infrared-based sensor.
The results of the study show that this system allows for the detection of counterfeit coins at a similar level to that of a trained expert.
According to the European Commission, 79% of counterfeit coins discovered in Europe in 2008 were two-euro coins.
The research is available in the scientific journal Sensors.