Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!rice!sun-spots-request
From: harp%terra.pkg.mcc.com@mcc.com (Christoph North-Keys)
Newsgroups: comp.sys.sun
Subject: Re: Severe Eyestrain--SUN Workstation problem
Keywords: Miscellaneous
Message-ID: <8903160000.AA18531@terra.pkg.mcc.com>
Date: 4 Apr 89 17:04:10 GMT
Sender: usenet@rice.edu
Organization: Sun-Spots
Lines: 59
Approved: Sun-Spots@rice.edu
Original-Date: Wed, 15 Mar 89 18:00:51 CST
X-Sun-Spots-Digest: Volume 7, Issue 224, message 1 of 13

>This person had worked on terminals for years, but developed blinding
>headaches and eyestrain after only two hours of working on a new SUN
>workstation with white background, black lettering.  She is also one of
>those people who can detect fluorescent light flicker (when others can't).

It's almost tradition for the computer-bound to eventually turn off all
lighting in their office in an attempt to avoid glare and flicker, and it
seems that's is high time we tried to analyze and solve the eyestrain
problem.  In humble pursuit of this goal, I am including my personal
impressions.  Let me point out that all points stated were arrived at
through empirical means, and that therefore I may be in error.

Factors believed to contribute to eye fatigue/degradation in computing:

1.  Working with flourescent lights rather than incandescent will
    produce the visual equivalent of the audible "beat" between two
    musical notes not quite in tune. This produces eye-strain.

2.  Working with reflections from other light sources in the monitor
	will tend to cause mental and visual strain due to the ambiguity
	between the displayed and reflected images (glare), and due to
	conflicting visual impressions of focus depth.

3.  Working on monochromatic monitors causes a type of eye fatigue due,
    apparently, to a lack of stimulation variance.

4.  Working for extended periods without periodically focusing on objects
    at different ranges, particularly in cubicles and windowless
    offices, may contribute (as does reading) to gradual degradation
    of the eyes' ability to adapt to varying focal distances.

Recommendations for the computer-bound, based upon preceding:

*	find a comfortable location with a view.
*	place your monitor and keyboard so that your gaze can easily rest
	(and shift focus depth) by shifting to an outside view.
*	use incandescent lighting on materials when lighting is necessary.
*	avoid flourescent lighting like the plague.
*	arrange to have a glare- and reflection-free view of the monitor.
*	sit at a comfortable distance from the monitor, preferably over 2 ft.
*	take advantage of a colour monitor whenever possible. 
*	arrange to use coherent, easy colours in your work environment.
	(ex:  MediumGreen, MediumBlue, RedBrown, Gold, Parchment, Black)
*	use easily readable fonts, fontsizes, and linewidths.
*	if trapped with a monochrome monitor, I find it usually more
	comfortable to use white characters on a black background.  This
	can be accomplished by:

	1.	On a Sun console:  echo -n '^[[q'     /* where ^[ is and esc */
	2.	In SunView      :  use the '-i' option to suntools
	3.	In X11          :  use the '-rv' options to tools or the
		                   '*reverseVideo:true' resource.

*	seek more information.

Best of Luck,

-Christopher North-Keys, harp%mcc.com@uunet.uu.net
 SysAdm, Pkg/Int, MCC.