By Andrew Liszewski
If you’re the paranoid type and have diligently worked to keep your personal details, including fingerprints, out of various government databases and the like, you might soon want to start wearing tin foil gloves as well. That’s because a company called Advanced Optical Systems has developed a device they call the AIRprint which can collect fingerprints from up to 6 1/2 feet away. It uses a pair of cameras that have just 1.3MP of resolution each, but adding polarized light into the mix apparently allows them to capture fingerprints that are detailed enough to be analyzed. MIT’s Technology Review explains how it works:
Slightly smaller than a square tissue box, AIRprint houses two 1.3 megapixel cameras and a source of polarized light. One camera receives horizontally polarized light, while the other receives vertically polarized light. When light hits a finger, the ridges of the fingerprint reflect one polarization of light, while the valleys reflect another. “That’s where the real kicker is, because if you look at an image without any polarization, you can kind of see fingerprints, but not really well,” says Burcham. By separating the vertical and the horizontal polarization, the device can overlap those images to produce an accurate fingerprint, which is fed to a computer for verification.
The current prototype has a few limitations in that it can only scan one finger at a time, it has to remain at a fixed distance in order to produce accurate results, and the processing time clocks in at around 4 seconds. But future versions will be able to handle multiple fingers at once, even if the person is in motion, in less than a second.