Understanding the unique nature of the iris

“The eyes are the windows to the soul” is a common phrase, as interpreted from the Bible verse, Matthew 6:22-24. The saying is appropriate when describing the iris, as it is responsible for allowing light into the eye by expanding and shrinking the pupil. In this section, we’ll study how scientists began to evaluate the eye as an identifier as early as 1885. We’ll then take a look at why the iris is an optimal biometric, and following this, examine the structure of the iris.

Let’s begin with the evolution of iris recognition.

Recognizing uniqueness

Interest in using the iris to identify someone began as early as 1885. A French police officer, Alphonse Bertillon, designed a system to identify prisoners using bodily measurements, called the Bertillon system.

Concurrent to this development, Bertillon began investigating the use of the iris as an identifier. In the following screenshot, we see...