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banner image: Biometrics guide

Iris scanning measures patterns on the coloured part of the eye - the iris.

The tissue has a unique pattern of markings which does not change and is different for each eye.

Iris scanners read from the outer edge towards the pupil, detecting and plotting the markings.

Data is saved and stored within a chip, on a passport or ID card for example, which will be verified when the eye is scanned in future.

While iris scanning is fast and accurate, its accuracy can be affected by objects obscuring the eye and may not be suitable for people with cataracts.


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