The visual texture of the human iris is determined by the chaotic morphogenetic processes during embryonic development and is supposed to be unique for each person and each eye. An iris image is typically acquired using a non-contact imaging process: capturing an iris image involves cooperation from the user, both to register the image of iris in the central imaging area and to ensure that the iris is at a predetermined distance from the focal plane of the camera. The iris identification technology is believed to be extremely accurate and fast.

J.L. Wayman, A.K. Jain, D. Maltoni and D. Maio, Biometric Systems - Technology, Design and Performance Evaluation, Springer, 2005.

A. Lumini and L. Nanni, "When Fingerprints Are Combined with Iris - A Case Study: FVC2004 and CASIA", International Journal of Network Security, vol.4, no.1, pp.27-34, January 2007. Abstract

A. Lumini and L. Nanni, "Empirical Tests on BioHashing", NeuroComputing, vol.69, no.16, pp.2390-2395, October 2006. Abstract