(This Idea is more generic than the current category, but one of
the alternatives, "Computer:Web:Identity", is just as specific as
the "Business:Credit Card:Security" category. We need a more
generic "Identity" category somewhere!)
Retinal scans, for uniqueness of personal identification
purposes,
are widely known to exist. This variation on the theme,
however,
seeks to close a loophole in the security of existing retinal
scanning systems.
In various stories the bad guys kill someone, extract an eyeball,
and put it against a retinal scanner. It then allows the bad guys
to
enter an otherwise-secure location. The scanner needs to check
for a living eyeball!
Well, it occurred to me that since the thing actually scanned is
the pattern of blood vessels feeding the retinal cells of the
eyeball, and since it is known that as the heart pumps
blood,there
are detectable surges/pulses in the body's arteries, then those
pulses should be visible to a higher-resolution retinal scanner,
so
long as it does more of a video scan, instead of a single-image
scan, of the retina. (On the inside of my own arm-elbow, I can
see with my own eyeballs pulses of the main arm-artery. The
arteries in the eyeballs are more like capillaries, but the pulses
should still be detectable.)
The pattern of blood vessels in the retina still needs to match
the system record, of course --but If the pulses are not there
(or even are very fast due to stress of
coercion), then the security system can refuse access to
whatever
room(s) it guards.