Iris Recognition’s Theory and Characteristics

Iris is the ring-shaped colored structure circling the pupil. Each eye’s complicate and unique pattern makes iris recognition an ideal identification method. The iris pattern was picked up by using near-infrared illumination, then the pattern will be extracted to an iris template, for comparison.

Iris pattern is a complex with the effects of texture, pigmentation, fibrous tissue and blood vessels within the iris,and it is also effected by the random conditions at the embryo development stage. The patterns of one person’s two eyes are different from each other.The genetically identical twins have different iris patterns. The duplication of iris pattern cannot be made even by cloning technology. The possibility of two irises having identical pattern is far less then any other parts of human body.

Iris recogntion is to verify person’s identity by comparing the similarity of the features included in the iris image. It usually has these 4 steps,

1．The capture of iris image
The eye area will be photographed by the specific equipment.

2．Pre-Processing of iris image
The raw image of the iris will be processed, to an iris template, which meets the requirement for extraction of iris feature points

3．Feature points’ extraction
The feature points will be extracted from the iris template by using algorithm, and the points will be encoded.

4．Matching
The feature point’s code will be compared with the codes in the database, and the match conclusion will become the result of verification.

Iris Recognition’s Advantages, compared with other biometric methods