I have recently run across an interesting patent application from Sarnoff Corporation that may have profound privacy implications. The application, titled “Method and apparatus for obtaining iris biometric information from a moving subject” describes the system that would be necessary to make the scenes in the movie Minority Report a reality.
What Sarnoff describes is a collection of iris cameras that repeatedly scan a person, even if they are fairly far away and in motion, until a usable iris image is captured. Just like the movie, people could be scanned as they enter a building or walk down their street, and the iris information could be used for identification.
Traditionally, face recognition has been used for this kind of task, but face recognition systems have not been very accurate. Iris recognition is far more accurate, so a ubiqutous, highly accurate, covert identification system may soon be a reality.