In article <HUCKA.94Dec6173609 at krusty.eecs.umich.edu> hucka at eecs.umich.edu (Michael Hucka) writes:
>I've been trying to determine what is the minimum presentation time of a
>visual stimulus that will allow a human observer to extract *some*
>information. Of course, this is going to be very task- and
>experience-dependent, but for recognizing simple forms or making simple
>discriminations, what is generally accepted as being a valid lower limit on
>exposure time?
I don't believe there is any lower limit to exposure duration as
long as you maintain the energy of the stimulus constant (# of photons
delivered). If a person can see it with 10-20 msec exposure, you
should be able to deliver the image with the same energy within
1 msec or even 10 microsec and have practically the same effect.
All experiments you quoted have the problem of proportionally smaller
stimulus energy as the duration is reduced. Therefore, the lower
limit reported may simply be due to threshold for stimulus strength
rather than that of exposure duration.
All this assuming you don't get anywhere near the level of power
where optical elements and photopigments start to behave non-linearly.
You can't do these exeriments with a CRT display.
Izumi Ohzawa
