The photographing of one’s iris is undoubtedly the least intrusive technique in the examination of the eye’s biometric characteristics.
Only a ordinary CCD camera is used, and there is no need for a direct physical contact between the user and the machine, making it more comfortable to use. In addition, this technique has above average identification rate.
It is not widely used because of it’s high cost , but it is often applied in areas where security is top priority. An important caution is that the photo taken be detailed enough, so the characteristics necessary for the identification can be seen clearly. At the taking of the photo, the machine searches for the boundaries of the iris, focuses on them, and takes the picture. This can be done two ways; either actively or passively.
When taking the picture actively, the user must look directly into the camera in a way that the distance between his /her eyes and the lens falls between 15-30 cms.
At the passive method however, this proximity is not necessary ; a comfortable 30-100 cms is enough, since the machine finds the iris and focuses on it automatically.
Iris diagnostics can also be used to measure the health condition of the user. By examining the pupil, the machine can tell if the user is tired, or under the influence of drugs or alcohol