The iris, like all biometrics, is a feature that uniquely belongs to a single person; thus, it can be used as a distinctive identifier. Iris recognition, while not new, has gradually emerged as an effective biometric for ascertaining identity quickly and in a manner that does not have the same criminal connotations, cleanliness issues or quality problems as fingerprinting. For this reason, iris recognition is gaining traction in physical and logical access control systems.
Because of its reliance on very small templates, iris recognition is also attractive from a storage and performance perspective. The confidence in the technology is on the rise, thanks to the successes of large government programs, as well as the fact that iris cameras are now commodity items. In the end, these factors are all contributing to a marked increase in the rate of adoption in markets such as law enforcement and the military, to civil programs such as travel document issuance and border crossing systems, and even commercial applications — especially banking.
The Commercialization of Iris Recognition
The idea of using iris for personal identification was originally proposed in 1936 by an ophthalmologist. In 1987, two additional ophthalmologists received a patent for their iris recognition technology. John Daugman, Ph.D., then at Harvard, worked to develop computer algorithms for the concept and later, the three men founded Iridian Technologies, one of the early biometrics companies. In 2008, the Daugman patent expired and the technology continued to advance with R&D efforts by a number of innovative companies, leading to the adoption of iris technology in a wide range of programs and applications.
A typical iris has at least 200 unique, identifying characteristics that can be used for comparison. Iris recognition is basically the matching of those 200 unique identifying characteristics within the iris against other images in a database. Iris recognition begins with capturing a photograph of the eye. No “scanning” is involved; rather, iris images are acquired by taking a photograph in infrared light.
The accuracy afforded by iris recognition, together with its fast search speeds (140+ million eyes per second) and small templates (1 million iris templates can be stored on just one gigabyte), make it an attractive method for identification — often more so than fingerprint or facial image comparisons. These attributes also make it viable for even the largest identity programs.
Accuracy and Performance
The U.S. government has been testing biometric vendors since the earliest days of the industry, in order to establish objective metrics for comparing technologies and to support users in making procurement decisions. The objective, non-biased, scientific approach of the National Institute of Standards & Technology (NIST) makes its tests the gold standard of accuracy assessment.
IREX III was the first independent test of one-to-many identification using a large, real-world dataset. The finding of the test was that iris is indeed a viable biometric for large-scale identification and an order of magnitude more accurate than face. The test also concluded that enrollment and search of both eyes offers better accuracy than a single eye.
IREX IV, released on July 11, 2013, compared the performance of iris algorithms from leading providers on operational databases of more than a million iris records.
Here are a few iris performance statistics:
• The false non-match rate is less than one percent using two eyes. Using a single eye, results are nearly as good.
• Iris-match speed is 140+ million eyes per second.