🚀 go-pugleaf

nelsonm@leela.cs.orst.edu (Michael Nelson) writes:

>In <LAUB.92Aug25194952@laub.Software.Mitel.COM> laub@Software.Mitel.COM (Boniface Lau) writes:

>>Does anyone have a medical explanation on why fluorescent light gives
>>headache? 

>I think my pen test may provide insight.  Try wave a pen or similar
>item in from of the minitor.  In many cases I notce that there is
>a definite strobe affect.  My dad also noticed that the early mac
>screen sometimes appeared to flicker when seen through peripheral
>vision (better at detecting motion).  

>I believe the problem may have a lot to do with the screen refresh
>rate, and the flourescent lights mixing and producing a low frequency
>(10hz?) light fluctiation that is detectable enough to cause strain.
>Of course I could be wrong.

Some study somewhere found that under fluorescent lights, many 
people's iris subtly contract and expand, responding to the flicker of
the lights. This seems on the face or it absurd, given the lack of 
perceivable flicker, but since the rods&cones have "persistence of 
vision" effects, while the iris doesn't, it may make some sense. How 
the iris "perceives" light density I don't know, but that may have 
something to do with eyestrain/headaches under fluorescents. I hate 
'em, and turn them off whenever I can. The biggest reason for 
fluorescent lights being so universal is that they use 10% of the 
power of indandescents. Now that the new long-lasting non-fluorescent 
low-power bulbs are on the market, that may change again.

>PS. Anyone bothered by the high pitched wines that many manitors seem
>to produce.  

There was a study done by (I think) the NIH that showed that women in 
particular are affected by the high-pitched whine, and that their 
responsivity to that frequency varied depending on their point in 
their cycle. No joke here, though various ones could be created. There
is great variability between individuals on frequency response, as the
responses in this group on this point indicate.

>>--
>>Boniface Lau    (613) 592-2122 ext. 3042    Boniface_Lau@Mitel.COM
>>Mitel Corp.  				    
>>350 Legget Drive, Kanata
>>Ontario, Canada, K2K 1X3
>--
>Michael Nelson

Michael Jensen
Electronic Media Manager
University of Nebraska Press
jensen@unlinfo.unl.edu
standard disclaimers in effect