Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!wuarchive!uwm.edu!rpi!uupsi!rodan!jfbruno
From: jfbruno@rodan.acs.syr.edu (John F. Bruno)
Newsgroups: comp.sys.atari.st
Subject: Re: my eyes are killing me...
Message-ID: <4077@rodan.acs.syr.edu>
Date: 30 Jul 90 04:11:55 GMT
References: <1921@gmuvax2.gmu.edu> <32129@cup.portal.com> <1618@oucsace.cs.OHIOU.EDU>
Reply-To: jfbruno@rodan.acs.syr.edu (John Bruno)
Organization: Integrated Healthcare Technologies, Inc.
Lines: 39

In article <1618@oucsace.cs.OHIOU.EDU> bwhite@oucsace.cs.OHIOU.EDU (Bill White) writes:
 >In article <32129@cup.portal.com> Bob_BobR_Retelle@cup.portal.com writes:
 >>The biggest problem is the relatively close distance between the monitor
 >>and your eyes.  It strains the muscles in the eye to keep focussed on
 >>a plane at the distance of a typical computer monitor for long periods of
 >>time.. (it's a lot easier on the eye when it's focussed at "infinity", or
 >>far away...)
 >
 >	Uh, I'm not sure that's correct.  If I remember correctly from my
 >days of dissecting cow eyes, the lens is naturally in a contracted state,
 >and the muscles pull it "flat" (ie focussed at infinity).
                                              ^^^^^^^^^^^    
                                              at a near point

Actually, eyes are in a more convex state, or focused on infinity when they 
are at rest.  The reason that people lose their close range vision with age
is that the lens loses flexibility with age and can't be pulled flat enough.

 >	I suspect that this fellow's problem might be that his vision is
 >slightly poorer at close distances.  I would encourage him to go see an
 >optometrist and get a full eye exam.  Or it could actually be illumination
 >levels, that can cause eyestrain too.  Or his monitor could be out of focus,
 >or jittering up and down, or otherwise bad in some way.
 >	Finally, there is one other possibility; it might be that he has a
 >flickery monitor (especially if he's using a 50Hz monitor); I often get
 >headaches from fluorescent lights that are old enough to "hum" at 60Hz,
 >even if I'm not consciously aware that they're flickering (ie it's too fast
 >to see unless you're looking for it).
 >	
 >>BobR

It's also a good idea (as everyone has been saying) to get into the habit
of periodically looking at a distant object.  I do this now without even
thinking about it.  I'm in front of a monitor all day long (8 hours, anyway)
and haven't had headaches or any kind of vision trouble.  I also have one
of those anti-glare screens at work that cuts down all of those nasty
particles that computer monitors spew at your face.

---jb