Researchers develop sensor for 'internal fingerprints’

A new imaging system developed by scientists that reads an “internal fingerprint” rather than external features promises to defeat fake finger hacking and other challenges raised by unreadable fingerprints.Developed by researchers from The Langevin Institute, Paris, the reader uses a special variant of an imaging technology called optical coherence tomography (OCT).Most optical fingerprint sensors today produce images by reflecting light from areas where the skin does not come in contact with a glass plate, a technique that captures details from only the very top layer of skin.However, this device images the “internal fingerprints,” which have the same pattern as external fingerprints, but are about half a millimeter below the skin's surface.The researchers report their results in the journal Biomedical Optics Express, from The Optical Society (OSA).Egidijus Auksorius, postdoctoral researcher, The Langevin Institute writes that despite the widespread use of commercial fingerprint sensors, problems with the devices persist. For instance, up to 5 percent of the population have difficulties using the sensors because their fingerprints are flattened from old age or damaged by routine manual work or sports such as rock climbing.To combat these problems Auksorius worked with Claude Boccara, a professor who specializes in scientific instruments at The Langevin Institute, to develop a new “internal fingerprint” sensor.While standard OCT systems gather 3D data and often require sophisticated lasers systems and light detectors, which can get expensive. Auksorius and Boccara simplified their system by using a modified version of OCT called full-field OCT, or FF-OCT, which was invented by their laboratory and developed in the early 2000s.The main advantage of the FF-OCT system is that it can take a 2D image of the fingerprint directly, saving time and making the data processing simpler and cheaper. Because not everyone's internal fingerprints are located at the same depth, the researchers also developed a method to first take an image of the fingertip at an angle. The first image was used to determine the depth of the internal fingerprint, and then a second image of the fingerprint itself was taken. The system can also image sweat pores, which provide an additional means of identification.Currently the system is about shoebox size and Auksorius is working to further shrink it. The biggest and most expensive element in the system – a specialized infrared camera – cost about $40,000, but the team recently acquired comparable images using a camera less than one fifth the cost. Auksorius estimates that a complete device using the new camera could be constructed for less than $10,000. While the price is still significantly higher than standard fingerprint sensors, Auksorius predicts that the new device could find a market dedicated to imaging problematic fingerprints or in areas where security is a particular concern.”We showed that the internal fingerprints could be imaged with a relatively simple and inexpensive system,” Auksorius said. “Furthermore, recent results with the new camera show that the system can potentially be a commercially viable solution.”The team has plans to soon test the device in Turkey, where 100 people will have their fingerprints scanned. They are also working to further improve the imaging speed and depth capabilities of the system.

Also in the news:

Identity Week launches call for speakers UIDAI to incentivise biometric Aadhaar payments Ievo fingerprint reader keeps CPNI approval