The sensor, incorporated in optical computer mice, is usually used to guide cursor movement, but can also be used as a counterfeit coin detector. This has been demonstrated by a prototype developed by computer engineers from the UdL, whose details can be consulted openly and for free in the scientific journal Sensors.
"We have implemented a counterfeit two-euro coin detection system by comparing patterns obtained with an optical mouse sensor", Marcel Tresanchez, one of the authors of the study, explains to SINC. According to the European Commission, 79% of counterfeit coins discovered in Europe in 2008 were two-euro coins.The coin is placed in a positioning device and is rotated to detect forgeries. The sensor, situated a few millimetres away, is employed to capture 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 researcher does explain that not just any optical mouse sensor will work, as images must be captured in real time, with a minimum resolution of 15x15 pixels (the team used 30x30 pixels). It is also better to use an LED- or infrared-based sensor, and not laser technology, as these[sic] provide images that are too wide.
The results of the study show that this system, devised to complement forgery identification techniques, allows for the detection of counterfeit coins better than any layperson could, although at a similar level to that of an expert trained to do so.
The authors have also applied the same method to design an "encoder" or rotating codifier (which counts the angular movement of an axis) using the optical mouse sensor.
Marcel Tresanchez, Tomàs Pallejà, Mercè Teixidó y Jordi Palacín. "Using the Optical Mouse Sensor as a Two-Euro Counterfeit Coin Detector". Sensors 9(9): 7083-7096, 2009 (Open Access).
SINC | EurekAlert!
Factory networks energy, buildings and production
12.07.2018 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH
Manipulating single atoms with an electron beam
10.07.2018 | University of Vienna
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
13.07.2018 | Event News
13.07.2018 | Materials Sciences
13.07.2018 | Life Sciences