A laser hits finger veins with a ‘poof,’ and a new biometric tool is born
A team of academic and industry researchers say they have created a biometric scanner that uses light and sound to build detailed three-dimensional images of finger veins.
The researchers say in a new paper published in the journal Applied Optics that the scanner was 99 percent accurate in biometrically accepting or rejecting an identity. Thirty-six subjects were tested using the photo-acoustic tomographic system and a custom matching algorithm.
It is reasonable, the scientists claim, to expect a similar scanner to be included in smartphones as biometric scanner designs get smaller and ultrasound components make their way to the handheld devices.
Team members came from the University of Buffalo’s optical and ultrasonic imaging lab and the school’s computer science and engineering department, as well as NEC Laboratories America Inc.
A summary about the work makes a perhaps unappetizing comparison to describe the process. A laser illuminating a finger makes “a sound much in the same way that a grill creates a ‘poof’ sound when it is first lit.”
The device records the noises using an ultrasound detector to create a three-dimensional image of the veins. It is the first time biometric authentication of fingers has been able to reveal depth, according to the paper. It reportedly is also the first time that photo-acoustic tomography has been used in this way.
The vein imaging process yields highly detailed images that are unique to each individual. Spoofing an image, “is basically not possible,” University of Buffalo team leader Jun Xia is quoted saying in the summary published by OSA, The Optical Society.
The more fingers (up to four for each hand) scanned for vein recognition, the more accurate the results, according to the paper.
Typical bulky photo-acoustic tomographic devices were found to be impractical for this task, leading the researchers to make their own machine including an imaging window that accommodates hands in a more comfortable position for scanning.