Path: utzoo!attcan!uunet!clyde.concordia.ca!mcgill-vision!snorkelwacker!usc!ucsd!pacbell.com!decwrl!shelby!eos!jbm
From: jbm@eos.UUCP (Jeffrey Mulligan)
Newsgroups: comp.graphics
Subject: Re: My eyes are sore ...
Message-ID: <6985@eos.UUCP>
Date: 1 Aug 90 16:49:37 GMT
References: <12453@rouge.usl.edu> <2790@bruce.cs.monash.OZ.AU>
Organization: NASA Ames Research Center, California
Lines: 30

damian@bruce.cs.monash.OZ.AU (Damian Conway) writes:

>In <12453@rouge.usl.edu> pcb@gator.cacs.usl.edu (Peter C. Bahrs) writes:

>>After several hours at the machine looking at text, high res graphics,
>>and movement, my eyes tell me to take a break. What can be done?

>They [eyes] get
>tired of focusing at 1-3 feet.

...

>Resolution contributes to ease of recognition and hence decreases psychological
>strain but does not help the physical eye strain caused by close focusing (as
>far as I can determine.)

>>I am looking for some research references to optical solutions for eye strain.

>No idea, but I'd be skeptical.

If D. Conway's diagnosis is correct, then there is an extremely simple
optical solution:  a pair of reading glasses.  Something around 2 diopters
should put the screen at optical infinity, for a viewing distance
of about 18 inches.

-- 

	Jeff Mulligan (jbm@eos.arc.nasa.gov)
	NASA/Ames Research Ctr., Mail Stop 262-2, Moffet Field CA, 94035
	(415) 604-3745