retina/cornea scanners

UrbanXrisis

are there retina/cornea scanners out there? or is that just a fabrication of movies? If there were these types of eye-scanners, what do theses scanners scan for to distingush one eye from the other?

Danger

I'm not sure about the corneal ones, but the retinal scanners read the pattern of blood vessels in the back of the eye. Like fingerprints, no two people's are the same. If 'corneal' ones exist, I suspect that it's a misnomer. They probably read the specific colour pattern of the iris. I don't really know that much about them, though.

UrbanXrisis

is there a link as to where i can find more information on retinal scanners? I've been looking online and cant find much about it

Danger

I don't really do much net-surfing, so I don't know of any sites offhand. The field that covers such devices is called 'biometrics'. I'd suggest that as a Googling jump-off point.

NoTime

Don't think there are cornea scanners.
That's the clear outer layer of the eye.
However, iris scanners seem to be an up and coming thing.
In addition to Dangers suggestion you could also try <iris scanner> in Google, it brings up a number of hits.

dav2008

Isn't it possible for these blood vessels to change over time? Blood vessels can pop, can't they?

Danger

True, but I suspect that they still maintain position, regardless of whether or not they're damaged. Someone from Biology should deal with that one. Also, multi-point matching is probably used, the same as with fingerprints. A cut, blister, wart, etc. doesn't prevent a match based upon the undamaged part of the finger. As far as that goes, though, I haven't seen anything about retinal scanners lately. Maybe they were phased out for just that reason.
I just happened to notice that there's an article about this on 'How Stuff Works'. I haven't read it, but it should be helpful. Most of their things are very well done.
http://computer.howstuffworks.com/biometrics.htm