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Death to LCD backlights

Last response: in Computer Peripherals
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January 5, 2003 6:15:14 AM

I'm quite happy with the performance of my new Hitachi CML174 aside from one thing:

It hasn't alleviated the red eyes I get from staring at a computer screen for many hours every day.

I've done some searching around the net, but found very little in the way of definitive answers on what could be responsible for my bloodshoot monitor eyes. I'm positive it's related to the monitor as my eyes return to normal as soon as I go a day without looking at one.

Is anyone else experiencing similar red eyes or headaches from using LCDs -- despite the general concensus that LCDs alleviate all the eye/headache problems associated with CRTs?

I found a site that seems to bring into question some of the popular assumptions about LCDs and more specifically their CCFL fluorescent backlights. Here's the link:

http://cloanto.com/users/mcb/19960719lcd.html

Anyway, another site I read mentioned that fluorescent office lights actually refresh at 120Hz... not sure how or if that applies to CCFLs, but that would probably eliminate refresh rate as a major source of eye fatigue. Really, the only causes I can come up with are:

1. The artificial spectral distribution of fluorescent lights is somehow irritating to the eye. Not sure whether there's any empirical evidence to back that up though, and even if there was, not much I can do to change it.

2. Viewing conditions -- the dryness of winter/office air along with the extended periods in front of a monitor combined with a natural tendency to blink less when staring at a monitor contribute to overall dry, irritated eyes. This can be partially alleviated by blinking more, taking frequent breaks, getting eye drops, and/or using a humidifier.

3. High brightness -- this seems to come up time and again as a major cause of eye fatigue.

So, as a start I've just taken action to reduce brightness on my CML174. First, I ran the brightness down to 0. I can't beleive how bright this monitor still is at its minimum -- so to follow that up, I went into the video card's advanced color settings and took the brightness down another notch or two in software -- better! Next, i changed the Windows default text background from bright white to a mid-level gray. That works great for word processing, but since most websites define their own background colors, it won't work on them. Fortunately, a handy ad removal program called proxomitron that I've used for several years now actually allows you to replace web backgrounds with any tiled image you choose. So I created a gray one pixel gif image and I now have gray backgrounds for every website I surf!

Combined, these steps should filter a lot of the CCFL light that's coming through the screen without negatively impacting readability. We'll see whether any of this really makes a difference in a few days.

Well, that's where I stand right now, hopefully this is useful to someone. I'd be curious to know others' take on the whole issue.

--Gordo

More about : death lcd backlights

January 5, 2003 10:32:09 PM

why dont you get some sun glass'

i am in similar position to you, my cml174swxb is ariving tommorrow!!

but you have to consider that it may not actually be your monitor hrting your eyes, reading a book (or other activity which involves looking at something close to you intently for long periods of time) would also cause strain on your eyes.
January 5, 2003 11:01:50 PM

Oh yeah, reading causes eyestrain too, except what he's describing is nothing like it (and what I myself have felt from personal experience). When reading, given good light, I can read for 8 hours non stop, and maybe have slightly, very slightly redder eyes, but my eyes don't hurt or anything. With an LCD that's too bright, after 20 mins my eyes are red, and they hurt. After 3-4 hours, it really hurts to move em side to side, and it feels as if there's grains in em. Oddly enough, with a good CRT, this doesn't happen. Issue is, the way lcd's are, u need a bright backlight for good contrast, and it seems to impress many people when a monitor has 300cd/m^2 brightness vs 220 or something.

"If everything seems under control, you're just not going fast enough."
- Mario Andretti
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January 5, 2003 11:47:41 PM

maybe it's just me, but when i didn't work full time... i was on my computer all day long... around 18 hrs a day.. reading text, and doing all other stuff... and my eyes never bothered me.. and that was on a CRT... so i don't know ...but i never get "tired eyes" or whatever

Is THG Slightly Slacking??
January 6, 2003 3:52:17 PM

I also get red eyes from my CRT. Its not top of the line, a 19 inch princeton ultra 92, and I have the refresh rate at 85 hz, but my eyes are a little red from web surfing just a few hours a day. Now if I start playing games like back in october for 8 hours + straight my eyes will be completely bloodshot.

I am confident however than an LCD will fix this for me. I am also expecting to get an S-IPS LCD. The advantages of IPS are wider viewing angle, it is not as bright as an MVA and there is no light leakage so the black colors look completely black, the response time for the gray pixels(the slowest) are faster on an IPS. The hitachi CML 174 is not an IPS, however the CML181SX is using their S-IPS. From what I have heard there is no problem with ghosting on this panel.

Perhaps in the near future there will be a perfect solution for me(S-IPS , < 16ms response, 17 inch screen)
but good luck to you !
January 6, 2003 4:03:28 PM

<A HREF="http://www.gamepc.com/labs/view_content.asp?id=bigblack..." target="_new">read here</A>

As you can see they do not complain about ghosting when testing the games... the cons to this monitor however though are: 25ms response is not perfect, higher price for 18.1 inch screen(when the *** are they gonna lower this), the not so sexy bezel

Quote:
Color contrast seems to be greater with the Hitachi monitor as well, although we did notice that the NEC 1920NX monitor can bring out much greater levels of brightness compared to the Hitachi CML181SXW-B. The default configuration of the Hitachi screen has the brightness set to 100%, and still isn't incredibly bright on screen, which means a low brightness level

<P ID="edit"><FONT SIZE=-1><EM>Edited by NoTiG on 01/06/03 01:05 PM.</EM></FONT></P>
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