THIS MAY SOUND incredible but the way technology is growing this will shortly be possible. Research by Sammy Phang, Queensland University of Technology’s Faculty of Built Environment and Engineering scholar, helps overcome one of the final obstacles to application of iris scanning technology to unlock our homes, access bank accounts and log on to our computers. Of all the biometric technologies used for human authentication today, iris recognition is thought to be the most accurate. Iris is an externally visible coloured ring around the pupil of every human eye and is absolutely unique. It exhibits a distinctive pattern and the chance of two irides or irises (plural of iris) being identical is estimated at 1 in 1078.

The patterns in the human iris are defined when the individual is about a year old and remains constant (barring trauma, certain rare diseases or change that may occasionally ensue from some ophthalmologic / surgical procedures.) This means that once a subject is enrolled, the need to re-enrol is lower compared to other biometric identification options, where changes in voice timbre, weight, hairstyle, finger or hand size, etc, necessitate such re-enrolment.

By using iris recognition it is possible to confirm the identity of a person based on who the person is rather than what the person possesses, such as ID card or password. It is already being used around the world and it is possible that within the next 10 to 20 years it will be part of our everyday life.

Sammy Phang in her media interaction said although iris recognition systems were being used in a number of civilian applications, it was not yet perfect. "Changes in lighting conditions change a person’s pupil size and distort the iris pattern," she said. "If the pupil size is very different, the distortion of the iris pat-tern can be significant, and makes it hard for the iris recognition system to work properly." To overcome this flaw, Sammy Phang has developed a technology to estimate the effect of the change in the iris pattern as a result of changes in surrounding lighting conditions. "It is possible for a pupil to change in size from 0.8 mm to 8 mm, depending on lighting conditions," she said. By using a high-speed camera which could capture up to 1,200 images per second, it was possible to track the iris surface’s movement to study how the iris pattern changed depending on the variation of pupil sizes caused by the light. Tests conducted using iris images showed it was possible to estimate the change on the surface of the iris and account for the way the iris features changed due to different lighting conditions. By using iris recognition it is possible to confirm the identity of a person based on who the person is rather than what the person possesses, such as ID card or password.