Biometric identification to replace PINs and passwords
The iris can serve as a human bar code, its unique features captured and translated into a biological personal identification number (PIN). Iris scanning is just one technology in the burgeoning field known as biometrics. The word "biometrics" originally meant the statistical study of biological variation. However the term now also refers to technologies that analyze human traits for security purposes.
Many groups are developing biometrics to replace or supplement PINs, passwords, and access cards. In this way, banks and other businesses hope to reduce theft, improve security, and make consumer transactions more convenient.
Fingerprinting is the most widely known biometric, but other approaches, such as face recognition, hand geometry, voice printing, and signature verification, also have potential. Calculating the degree of security actually provided by these various biometrics is a difficult task, however, and researchers are still exploring this problem, even as actual devices are being rolled out into the marketplace.
Recent cases of identity theft have heightened the need for methods to prove that someone is truly who he or she claims to be. Biometrics may solve this problem, since a fingerprint or an iris is undeniably connected to its owner. The system can then compare scans to records stored in a central or local database or even on a smart card.
Iris scanning is one of the most secure biometrics, simply because of the large number of independent features that can be coded. Consisting of fibrous and vascular tissue and pigment granules, the iris possesses about 266 measurable features. No other part of the body has this many useful attributes; according to ophthalmologists. Fingerprints run a distant second, with about 40 characteristics.
Sensar in Moorestown, N.J., has incorporated iris scanning into ATMs. Eye scans ordinarily require a person to look directly into a camera and therefore can be intrusive for some people. Sensar has combined the iris-scanning system with an advanced camera setup that can detect the customer's eye from 1 to 3 feet away. Sensar licensed the camera technology from Sarnoff Corp., in Princeton, N.J. which originally designed it for the military so that high-flying helicopters could take pictures of tanks on the ground.
As a customer walks up to an ATM, a system of three cameras identifies his or her torso, head, and eyes, then zooms in on the iris, says Michael Negin, Sensar's chief technology officer and vice president. One of the cameras takes several pictures, which are then divided into a gridlike pattern and translated into a bar code. The entire process takes only a few seconds.
Contact lenses don't affect the image, and the software corrects for reflections from eyeglasses; however, scratches on the eyeglasses do distort the image and reduce comparison values.
The researchers also took advantage of another unique trait of the iris: the constant dilation and contraction that adjust the size of the pupil. The system now detects that subtle movement, to ensure that a live human being and not just a picture of an iris is in front of the camera.
Even identical twins don't have the same iris, though they may have the same face shape or even identical fingerprints. Proponents of other biometric technologies, such as face recognition, argue that this is a minor concern, since in the real world, most crimes aren't committed by an evil twin.
Continued in Part Two