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Why do electronic display screens make my vision blurry?

by iScience
Tags: blurry, display, electronic, screens, vision
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iScience
#1
Sep17-13, 10:43 PM
P: 342
what is intrinsically different about the light coming from electronic display screens vs the light everywhere else (light from the environment)? perhaps.. the brightness? but that shouldn't cause blurry vision. this deals with focuses.. anyone have any suggestions as to why this might be?
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rcgldr
#2
Sep17-13, 10:59 PM
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Perhaps after focusing on any object relatively close for a while could cause some people to have trouble focusing on distant objects after a while.
davenn
#3
Sep17-13, 11:24 PM
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any specific type of electronic display?

LED, LCD, Fluorescent, etc ??

Dave

russ_watters
#4
Sep17-13, 11:26 PM
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Why do electronic display screens make my vision blurry?

http://en.wikipedia.org/wiki/Asthenopia
iScience
#5
Sep17-13, 11:30 PM
P: 342
it's just LCD
Drakkith
#6
Sep17-13, 11:35 PM
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You say you have blurry vision. Can you elaborate? Are only distant objects blurry? Both near and far?
Is the display itself blurry?
SteamKing
#7
Sep17-13, 11:38 PM
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Some screen are very small, and you will strain your eyesight working too long trying to read the small characters and fine display features. Also, a lot of word processing and Acrobat readers use white backgrounds, which I find to be quite bright. Staring at these bright backgrounds will also introduce eye fatigue. Screen can also pick up glare from your surroundings, piling on the fatigue to your eyes.
CWatters
#8
Sep18-13, 02:24 PM
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There is very little that is inherently different. LCD screens contain polarisers so if you are wearing polarised sun glasses you might see strange effects but not necessarily those you describe.

Bright lighting causes the pupil to contract and may even make you squint through your eye lashes. This can create a pin hole camera effect that compensates for defects in the focusing mechanism in the eye. This is why people who wear glasses tend to peer at things through partly closed eyes when forced to read something without them.

The opposite effect happens under low light levels. The pupils dilate and this causes a reduction in the depth of focus making it harder to focus if your focal range is already limited.

I would recommend visiting an optician, explain the effect/problem to them and get your eyes tested.

I now have a pair of transitional focus glasses with the bottom designed for reading close up (eg the keyboard/books) and the top designed for reading my LCD monitor.
Pythagorean
#9
Sep18-13, 05:03 PM
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A bad refresh rate can do it.
Greg Bernhardt
#10
Sep18-13, 05:13 PM
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Quote Quote by iScience View Post
what is intrinsically different about the light coming from electronic display screens vs the light everywhere else (light from the environment)? perhaps.. the brightness? but that shouldn't cause blurry vision. this deals with focuses.. anyone have any suggestions as to why this might be?
Are you dealing with eye fatigue? I need to take a 10min break every 30min I'm at the computer or my eyes will feel wreaked by the end of the day. I'm talking bloodshot, dizzy, blurry, and feeling nauseous. Try to turn down the brightness and change the hue from a cold to warm color.
iScience
#11
Sep18-13, 05:51 PM
P: 342
since this was reposted in the medical sciences section, let me ask it this way: what is it about the light coming from my laptop that's causing my iris to contract (or relax)? i live in florida and it gets super bright outside (much brighter than the light coming from my laptop), and sometimes, when i forget my sunglasses, i am exposed to my bright surroundings but i don't recall ever getting blurry vision from that. i don't know very much about the eye, but i hope i'm not being too inaccurate when i say that the iris tends to contract or relax based on voluntary feedback from the brain; ie if something is close, i will have the natural response of wanting to contract my iris muscles to get the clearer image. When i first look at my computer screen everything looks fine but after about 8~9 hours my vision becomes so blurry it takes about sometimes a couple hours for me to recover. My point/question there was that, everything looks fine in the beginning, so what about the light coming from the laptop is generating a response from my iris such that it is constantly wanting to ""focus" ie contract, even though everything is in focus just fine in the beginning?

let me know if any of my wordings were unclear
Drakkith
#12
Sep18-13, 06:30 PM
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I think you need to elaborate on what your exact symptoms are, like I said in post #6.

You say you have blurry vision. Can you elaborate? Are only distant objects blurry? Both near and far?
Is the display itself blurry?
It appears to be normal eye strain from staring at a nearby object for extended periods of time. Note that this isn't a result of the light itself. There's nothing different about the light coming from a monitor that would cause this. It's because you're staring at something for an extended period of time.
http://en.wikipedia.org/wiki/Computer_vision_syndrome
http://en.wikipedia.org/wiki/Asthenopia
iScience
#13
Sep18-13, 06:38 PM
P: 342
ah sorry, the more distant an object is the better i can see it. and the more time i spend on my computer, the farther the 'clear' distance becomes. ie i have trouble seeing nearer objects.


and okay, thanks
Drakkith
#14
Sep18-13, 06:43 PM
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Quote Quote by iScience View Post
ah sorry, the more distant an object is the better i can see it. and the more time i spend on my computer, the farther the 'clear' distance becomes. ie i have trouble seeing nearer objects.


and okay, thanks
Hmmm. Interesting. I hadn't heard of this before. What happens to me is that I can't see far away objects because I've been focusing on something close for a long time.
CWatters
#15
Sep19-13, 05:28 AM
P: 3,154
Quote Quote by iScience View Post
When i first look at my computer screen everything looks fine but after about 8~9 hours my vision becomes so blurry it takes about sometimes a couple hours for me to recover.
I think someone already posted this but your description fits this perfectly...

http://vision.about.com/od/sportsvis...Asthenopia.htm

The issue is nothing to do with the light source. It's mostly to do with your eyes focusing on something at a constant distance. So in your break time don't go reading a book or playing with your phone as these will be roughly the same distance away from your eyes as the LCD screen.


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