From: djones@dcs.warwick.ac.uk (Kestrel)
Subject: Re: PSYCH: How 'bout this one...
Date: Tue, 23 Feb 1993 11:34:01 GMT
Message-ID: <1993Feb23.113401.18169@dcs.warwick.ac.uk>
Organization: Department of Computer Science, Warwick University, England


In article <1masuaINNigu@shelley.u.washington.edu> idr@cs.pdx.edu (Ian D Romanick) writes:
>
>
>The reason that HMD's tend to be harder on the eyes than a TV or monitor is
>that it is USUALLY very difficult to look away from the HMD screens.  While
>I'm at work programming I only spend about 30% of the time looking at the fixed
>screen.  If I were working in with a HMD, it would probably be closer to 80%.
>
        There is an additional problem due to the proximity of the screens to
your eyes. There is little muscular difference between looking 15 feet away
and looking 250 feet away. However, when we try to focus on objects that
are within about 15 feet (or somewhere near that) our accomadation system
is such that our eye muscles become more tense the closer to us the object of
focus becomes. Obviously if a HMD screen in only a matter of inches away
and our eyes are focused onto the actual screens (ie no optics making the
screens seem futher away), the eye muscles are totally tensed up and will take
a very short period of time to start screaming with pain. As an experiment,
(be very careful if you actually try it out, 5 mins is far to long a time)
                                                       ^^^
try looking at the tip of your nose for 5 minutes, and the try looking at a
distant object for the same period of time. Compare and Contrast.

                        Any soultions that don't require optics?

                                Darren Jones
                                djones@uk.ac.warwcick.dcs