Biometric modality: Eyes: Iris – what is it?
The iris is the coloured circular segment at the front of the eye that contains the pupil at its centre. The iris controls the size of the pupil to adjust the amount of light entering the eye. Iris recognition technology uses the unique patterns of the coloured tissue that form the iris. These patterns are captured by a camera operating in near infra-red wavelengths. The first iris cameras had to be close to the eyes (but not in contact with them) in order to record sufficient detail but technological advances now allow cameras to be placed several feet away and capture the irises of those on the move such as at an airport boarding gate. The system uses pattern-recognition algorithms, in a similar way to automated fingerprint recognition systems, to perform comparisons in both the biometric one-to-one (1:1) verification to authenticate a suggested identity and one-to-many (1:N) identification modes as a probe to search a database to establish if any of the other iris records provide a potential match.
NB refer to Sections 1 Overview (page 1) and 9 Annex (page 20) of the Biometrics Institute’s Understanding Biometrics guide for more information regarding one-to-one and one-to-many modes.