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Scientists also say a person's retina can change with age, while an iris remains intact.
And no two iris blueprints are mathematically alike, even between identical twins and triplets. EyeTicket Corp., headquartered in McLean, Virginia, is the exclusive provider of the technique for both airline passengers and personnel. A low-level incandescent light illuminates the iris so the video camera can focus on it, but the light is barely noticeable and used strictly to assist the camera. One of the frames is then digitized and stored in a PC database of enrolled users. The whole procedure takes less than a few seconds, and can be fully computerized with voice prompts and auto focus.