From: uselton@nas.nasa.gov (Samuel P. Uselton)
Subject: Re: SCI: 3-D images bad for eyes - research from Japan
Date: Fri, 9 Jul 1993 22:18:20 GMT
Organization: Numerical Aerodynamic Simulation, NASA Ames



In article <21j8o9$r4n@news.u.washington.edu> knights@gov.on.ca (Shawn
Knight) writes:

   In <21ge50$5rk@news.u.washington.edu> yuri@atr-sw.atr.co.jp
   (A.Tijerino) writes:

   >the object itself may seem much closer or much further away.  This 3-D
   >effect is achieved by using special goggles and a film which presents
   >two images of the object to be perceived -- one for each eye. 

   I assume they were using flicker glasses .. I don't like the test
   criteria for this .... I'd prefer to see the results of use two side
   by side LCD's or CRT's rather than blanking alternate eyes.  Who is to
   say it's not the flickering causing the abnormalities?

   Comments?

I thought it was well known to EVERYONE by now that you should change
the distance your eyes are focused at every so often.  That is just as
true when looking at a screen a foot or two away as when looking in a
head mount.  LOOK OUT THE WINDOW every few minutes!

The question that MIGHT be more interesting is to run the test but
*vary* the virtual distance to the focal object, to see if that is
"enough" or whether you should really take the headgear off and look
at a real distance.  (This is easier with the BOOM than with standard
head mounts.  nyaa nyaa.  :-) )

Sam Uselton		uselton@nas.nasa.gov
employed by CSC		working for NASA (Ames) 	speaking for myself