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Displays Biotech

Health Consequences of CRT Monitors? 306

DigiMan asks: "I was wondering, what are the effects of working on a CRT are on your health - long term. It has recently bothered me that EVERYONE seems to be switching to LCD's - I noticed that Bill Gates was one of the 1st people to do this, even when the cost was super high, and many, many government offices switched to the much more expensive LCD's - despite budget cuts and having to go with the lowest bidder strategy they operate under. Was this ONLY for style and space savings? Is there some health consequence that no one talks about publically. I know that they do emit very low amounts of X-Rays and have a 60Hz magnetic field as well as a 12.5 kHz electro magnetic field (for the raster scan). I work in front of typically 3, 19" CRT's for 12 - 16 hours per day at an average distance of 18". Can these magnetic fields cause Leukemia, or anything else? Is being behind the a cathode ray tube that bad for you?"
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Health Consequences of CRT Monitors?

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  • by suso ( 153703 ) * on Friday April 01, 2005 @05:19PM (#12114721) Homepage Journal
    I'm sure that CRTs affect your eyes. A local eye doctor told me once that this is because your eyes actually tend to focus about an inch behind the glass on your CRT because of the way the image is projected. Eventually this probably causes problems. Almost everyone that I knew before and after they started using computers (back in the 80s and 90s) had to get glasses within 6 months of using a computer with a CRT. Some of those people that I've talked to about this say that they most likely bought glasses because they were reading more or for longer periods of time. Unfortunately, I don't have any hard evidence to back up this claim (and many slashdotters will slam me for it) but its kinda obvious and I have a good gut feeling about it. Probably many other people feel the same way.

    There is also a book by an eye doctor named William Bates (kinda a punny name for April Fools) where he talks about how to restore your normal eyesight through training. He mentions in his book that reading at close distances strains your eyes enough to distort the lens or something like that.

    For reference, the rate of change of my eyesight (nearsidedness) has slowed down since I started using flat panels, but that could just be because I'm getting older. I would recommend taking breaks once or twice a day, going outside and looking out long distances.

    (I hope this wasn't some kind of weird April Fools Ask Slashdot article)
    • Even if it is a joke, it allowed for you to bring up a good topic. So how is that bad?
      • I don't know, maybe with my bad eyesight I failed to see that this might have been some kind of joke and everyone was going to slam me for it. I think the dangers of CRTs are still relavent. Especially since old used ones are now in abundance and probably lots of people are using them for special things like server consoles or multiple monitor setups.
    • There is also a book by the eye doctor named William Bates...

      As a prosperous young man, Dr. Bates was referred by his staff as Master Bates.
    • by bmw ( 115903 ) on Friday April 01, 2005 @05:25PM (#12114817)
      I'm probably an exception and just generally have strong eyes but I've spent the better part of my life behind CRTs and still have perfect vision. I'm very sure that sitting in front of a computer screen (of any kind) isn't good for your eyes but I still haven't developed any problems from it. I do seem to be getting carpal tunnel though :-\
      • Same for me. My only problem seems to have come about when everyone switched from the old white-on-black displays to having everything be black-on-white. Staring into a sea of bright white pixels to read black text seems to give me a headache after a while. I try to set stuff to display as white on black, but it causes a lot of other problems with "poorly designed" webpages, etc.

        • It's no problem for me because I only read this site. [] Other than the occasional /. session :)
        • One of the better comments I've seen about this:

          Would you want to stare at a lit flourescent tube for most of the day? Would would expect your customers to do this? Well, a CRT is a flourescent tube, and a window with a white background is a fully-lit flourescent tube. Guess what this does to your eyes ...

          The common white background is a visual metaphor for paper. But paper isn't a glowing flourescent tube. And note that publications that are often read outdoors (newspapers, paperback books) are usu
      • I got glasses before 2nd grade, over 30 years ago. My eyes progressively worsened until I started working long hours in front of computer screens during my 3rd year of college.

        My eyesight has not changed since then, over 15 years ago, and I've been a professional programmer all this time (to say nothing of long hours at home playing games or surfing on top of it.) Clearly from my anecdote, computer screens stop nearsightedness from getting worse.

        I shall now make pointless generalizations based on one a
      • I do seem to be getting carpal tunnel though :-\
        Porn will do that to you (sound of one hand clapping, etc).
        Your eyesight takes a bit longer ...
    • by Sycraft-fu ( 314770 ) on Friday April 01, 2005 @05:29PM (#12114854)
      I started using computers at age 5. At age 9 I had one with it's own dedicated CRT (they used the TV before that). I'm now 24. So, I did need to get glasses at 22, however that was for an astygmatism in my left eye, my right eye still has perfect vision.

      Now I'm a computer junky, I use them all the time, at work and at home. Until about a year ago, it was always CRTs. I now have an LCD at work, but still a CRT at home (which I am soon going to replace with another).

      So in my case, an excessive amount of CRT usage doesn't seem to have caused any nearsightedness. Also not being nearsighted is counter to my genetics, my mother and father are both nearsighted, as is my sister who doesn't make much use of computers and got her glasses much younger than I did.

      Again, just a personal anecdote and not a valid representation of the overall situation, but it runs completely counter to yours. I know it's compelling to think your experience is representitive, but it's very often not the case. Trust emprical research, not personal anecdotes.
    • I have firsthand experience to the easing of the eyes created by switching to LCD screens. I run an IT department at a trucking firm, and recently converted our dispatch department to LCD screens. Immediately there was a noticed difference; the dispatchers didn't get the headaches that they used to get at the end of the week from spending 5 days staring at a CRT screen, and they also commented on better eyesight in general (one dispatcher uses a higher resolution now that he can see the screen better).

      I t

    • I'm sure there are some bad effects from CRT's, both in eyesight and other health areas. But whatever those ill effects are, I'd wager that they're not near as bad as the effects of sitting on your butt for 12 to 16 hours a day.
    • The real reason: (Score:5, Insightful)

      by temojen ( 678985 ) on Friday April 01, 2005 @05:29PM (#12114858) Journal
      LCDs use less electricity, and don't flicker.
    • (I hope this wasn't some kind of weird April Fools Ask Slashdot article)

      my friends and I regularly get together and laugh over the health consequences of CRT monitors. I think its hillarious. One of my favorite topics is VDU WORK AND THE HAZARDS TO HEALTH [] its a laff riot!

      sarcasm aside, I guess it wouldn't be that suprising if it was a joke article.. seeing as how today is all about funny funny joke suprises! I for one am really suprised by all the funny funny joke stories. I fall for everyone!

    • I recently broke down and bought an LCD monitor because I'm having more trouble with my eyes. I'm only 24, and have experience issues focusing on the monitor, sensitivity to bright light, and headaches. Since getting this LCD, the problems have gone away a bit. I'm still tweaking the settings - brightness is an issue - but I think it's helped.

      With the LCD, I don't suffer from screen glare as with my CRT. That lets me keep the window open, allowing me more natural light and fresh air. I'm sure that all cont
    • In the '80s the computers I used had gigantic letters. Today the fonts are tiny (and I prefer it that way - I can fit more on the screen) and that means more time spent focusing on tiny minutia at close range - which leads to nearsightedness. My bad eyesight got worse faster after it became possible to fit 1280x1024 on a screen and the temptation to do so and fit 200 characters across the screen was too good to ignore for mere heatlh reasons. Now I'm beginning to regret it.
    • I also suffer from poor eyesight. What I've noticed is that I can spend more time in front of an LCD monitor without feeling the eyestrain I used to experience with a CRT. In the CRT days, I could only code for about three hours before I began getting severe headaches and that "sleepy eyed" sense of being visually tired. With the LCD, I can go a full workday (which may or may not be a good thing...) switching between Windows and CLI Linux without any noticeable irritation.

    • by ErikTheRed ( 162431 ) on Friday April 01, 2005 @05:34PM (#12114913) Homepage
      1) I've been wearing rigid gas-permeable contact lenses for 22 years now (not the same set, and I take them out at night you smart-asses). I notice that when I wear these versus glasses, I can stare at most monitors for a long time without significant strain.

      2) Use the best CRT monitor you can get your hands on. I've noticed that my eyestrain actually goes up working on my laptop versus my CRT (a 22" NEC MultiSync FP-series set to the highest possible resolution and very tiny fonts). It's one of those things you have to try for a few days before you realize how nice it is.
    • I have been using CRT Monitors since 1990 (I was 4, my love, my dad's commodore) playing price of persia and BASIC programming) well as of today, I spend daily 2-18 hours infront of one. My eye sign has never been bad, just slighly less than perfect before 2000. Now I have perfect vision, there for the use of it has no effect. Cycled around 20 CT monitors so far. I could possibly say that CRT's have no effect on your eyes as long as you excersise them (my uncle told me, that, I do it daily), which goes as
    • It's all about the flicker in a CRT.

      Like most of those reading this (who are employed, not still in school, or worse - unemployed), I spend the bulk of my day looking at a computer display. Last year, when my vision had gotten worse for the 4th year in a row, my eye doctor told me to stop looking at CRTs and start using LCDs. My boss got me a 17" LCD for my work system, and my (fantastic) wife got me an Apple Cinema Display for my birthday. Since then, I've gotten rid of the Cinema Display as I've gone

    • > would recommend taking breaks once or twice a day, going outside

      Who knew that being a smoker had any health benefits! I take at least that many smoke breaks a day...
    • I believe that CRTs have had a negative effect on my eyes.

      I developed slight nearsightedness at around age 16. It took another two years before I needed correction in order to drive.

      About two years after that, I started spending a *lot* of time in front of computers. It was my third year of university, and there were many long nights of coding in the lab. My eyes began getting worse at an alarming rate of -0.5 to -1.0 per year. My optometrist wasn't surprised when I told her how long I spending in fron
  • Yes (Score:5, Funny)

    by Anonymous Coward on Friday April 01, 2005 @05:19PM (#12114722)
    Hairy palms and blindness.

    Wait, that might be caused by something else...
    • I suspect the two activities may be related.
    • Hey, Is that contagious? It sounds like something that's been ailing me....
    • Zinc (Score:3, Interesting)

      by r00t ( 33219 )
      Zinc is important for your eyes. The US RDA is 15 mg of zinc. That means you're supposed to have 5 mg every day.

      Guess what activity makes you lose 5 mg of zinc? Uh huh. At 3 times per day, you've used up your daily dose of zinc!

  • Yes (Score:5, Insightful)

    by geekoid ( 135745 ) <<moc.oohay> <ta> <dnaltropnidad>> on Friday April 01, 2005 @05:20PM (#12114731) Homepage Journal
    they may cause you to loose a sense of humor and whine about stories posted on April 1st.
    • No, we're whining about _bad_ stories posted on April 1st. The signal:noise ration of /. varies, but it just seems like it's hit an all time low today.

      I've also never complained about the free crap .sig lines, so I'll do that now.

      Or maybe I'm just cranky. Two complaints in one post.
  • Bad for your eyes (Score:5, Informative)

    by freak4u ( 696919 ) on Friday April 01, 2005 @05:20PM (#12114732) Homepage Journal
    The 60Hz refresh is bad for your eyes, LCDs are nicer to your eyes in general. I've heard there's a bit of radiation, but I don't think anywhere near what a cell phone puts out
    • by snuf23 ( 182335 ) on Friday April 01, 2005 @05:24PM (#12114797)
      Modern CRTs and video cards can handle resolutions higher than 60Hz. Admittedly some stupid companies ship computers with the refresh rate set to 60. You should be able to run it at 72Hz or higher depending on your monitor, video card and resolution.
      I am running 1280x1024 res at 75Hz using a 5 year old video card and monitor.
    • by arodland ( 127775 ) on Friday April 01, 2005 @05:24PM (#12114800)
      Yeah, CRTs put out a bit of radiation; so do LCDs. Scientists have theorized that this electromagnetic radiation is, in fact, what allows you to see the picture on the screen.
    • Radiation from cellphones is at completely different frequencies from what is produced by CRTs and they have completely different biological consequences. Anyone who says that the amount of radiation from one isn't "anywhere near" that put out by the other, and expects that to be a useful statement, is clearly talking out of their ass. "I've heard" and this is moderated up. Please! I know this is April 1 but that's going too far.
    • Re:Bad for your eyes (Score:4, Interesting)

      by ePhil_One ( 634771 ) on Friday April 01, 2005 @05:35PM (#12114929) Journal
      The 60Hz refresh is bad for your eyes, LCDs are nicer to your eyes in general.

      LCD's have a different sort of refresh, the 60 hz isn't really a big deal unless you're talking about a fast moving action game. CRT's work by zapping phosphorous spots with an electron gun, immediately after being zapped it begins to fade, to perhaps 50% brightness in 20ms, about the time the gun makes a return trip. So a CRT pulses in time to its refresh rate; and wouldn't you know it, the AC current pulses at 60Hz, means some kinds of lights will also pulse at 60 Hz. Put the two pulses together and the can create an interference pattern that will drive some folks bonkers, strain you eyes subtly, etc. etc.

      An LCD pixel on the other hand works like a switch, the pixel is on, letting the back light through, until it is told to turn off. The 60Hz refresh rate only corresponds to how often the pixel "might" get told to change, there is no pulsing.

      Of course these are some gross generalizations and I'm sure someone will pop up to tell me how I have it all wrong, even when I'm right.

      • You are partly correct but this is wrong:

        " The 60Hz refresh rate only corresponds to how often the pixel "might" get told to change, there is no pulsing."


        "Since LCD monitors do not employ phosphors, refresh rate is not a concern. Basically, the transistors in the LCD remain open or closed as needed until the image changes. This can be a point of confusion for some consumers, however, since most graphics cards still "ask for" a refresh rate setting. This is due to the analog nature of existing graphic
  • monitor tan (Score:5, Funny)

    by DJ Haruko ( 798333 ) on Friday April 01, 2005 @05:20PM (#12114733) Homepage
    Well dang, if I can't get a tan from my monitor, where can I anymore?
  • by VAXcat ( 674775 ) on Friday April 01, 2005 @05:20PM (#12114746)
    Heck ya - every time a pixel switches from a 1 to a 0, the resultant decrease in entropic state causes a photon of bit radiation to be launched right at you! Fortunately, as it slowly erodes your frontal lobes, you lose the ability to care about it happening.
  • I, for one, welcome our new LCD overlords.
  • Mostly Desk Space (Score:3, Interesting)

    by vmcto ( 833771 ) * on Friday April 01, 2005 @05:20PM (#12114751) Homepage Journal
    "Was this ONLY for style and space savings?"

    For me personally, Yes. It's all about the style and convenience. I can actually see my desk now.

    For our SOC personnel that are in front of multiple large screens for an entire 8 hour shift, I think it is a nice side benefit that they are not being bathed in magnetic fields all day.

    But they still look cool and take up less space. Not too mention, generate a lot less heat.

    You do make an interesting point about being behind multiple tubes. I believe most measurements are made from some distance from the front of the tube.

    Once again in a scenario like a call center or in our SOC this would tend to be the case when you have rows of monitors.
    • Plus the LCD image is sharp and has perfect geometry. I don't think anything beats a decent LCD hooked up with DVI for coding and most office work (and browsing slashdot). (I can't speak for other applications because those are my only applications).
  • Um? (Score:5, Funny)

    by addaon ( 41825 ) <> on Friday April 01, 2005 @05:21PM (#12114753)
    If all of us inside the conspiracy have been keeping the secret from you this long, why would we suddenly tell you the deep, dark truth now? Because you asked nicely?
  • Hmmmm.... (Score:4, Funny)

    by MongooseKY ( 760783 ) on Friday April 01, 2005 @05:21PM (#12114754)
    *Stares intently trying to find the April Fool's joke in this post*
  • Yes. (Score:3, Funny)

    by CarrionBird ( 589738 ) on Friday April 01, 2005 @05:21PM (#12114761) Journal
    But we're not going to tell you.


  • by stecoop ( 759508 ) * on Friday April 01, 2005 @05:22PM (#12114770) Journal
    Like a poster said one time: google knows all who knows all; therfore, a quick google search for Radiation King reveals

    In episode 2F07, Grampa vs. Sexual Inadequacy. In it, Homer finds himself in his childhood home, and the living room wall has a shadow of Homer as a child burned into it by the Radiation King TV set. The scene then shifts to his memory of watching it in the refulgent radiation of TV the set in the process of creating that distinctive shadow on the wall.

    Thus, we have answered your questions: USE LCD until such time it is determined to produces some other kind of Sexual Inadequacy Radiation.
  • Even Bill Gates? (Score:4, Insightful)

    by PopeAlien ( 164869 ) on Friday April 01, 2005 @05:22PM (#12114774) Homepage Journal
    I noticed that Bill Gates was one of the 1st people to do this, even when the cost was super high ..yeah, cause I'm sure the cost is a big concern for him huh?
    • >> I noticed that Bill Gates was one of the 1st people to do this,
      >> even when the cost was super high
      > ..yeah, cause I'm sure the cost is a big concern for him huh?

      You don't get rich by writing checks!
    • Dude, he could plaster every square inch of the walls in his house with plasma screens and it STILL would NOT put a dent in his least from his perspective.

      Gates, I hate you because I envy you. ;-P
    • yeah, cause I'm sure the cost is a big concern for him huh?

      After Customs impounded his ultra-rare import Porsche, he was heard to remark "Well, there goes a million bucks". What I want to know is this: does he have those sexy 23" Apple cinema displays?

  • scientific tests? (Score:5, Insightful)

    by Comsn ( 686413 ) on Friday April 01, 2005 @05:23PM (#12114786)
    any scientific tests to show CRT cause eyesight problems?

    doctors say to take breaks, when doing lots of reading, be it lcd/crt/book/newspaper anyways...
  • 20-20-20 (Score:5, Informative)

    by HybridJeff ( 717521 ) on Friday April 01, 2005 @05:23PM (#12114790) Homepage
    Last time I went to the eye doctor (a month or two ago) he told me basically, that staring at monitors should have NO ill effects, as long as you take a break evrey once in a while. He phrased it as the 20-20-20 rule. Basically evrey 20 minutes, look at somthign 20 feet away for 20 seconds to prevent your eyes from getting strained.
  • Radiation (Score:3, Funny)

    by skroz ( 7870 ) on Friday April 01, 2005 @05:23PM (#12114791) Homepage
    Dunno, dude, I'm blind as a bat and have to get awfully close to my monitors. I've DEFINITELY noticed an increase in heat on my face since switching to the LCD.

    Go ahead, try it... put your nose up to your LCD. Feel the heat? That's your face cooking right there. Never had that problem with a CRT before. Brain cancer, sure, but no cooked face. I'd rather be pretty than smart.
  • by klui ( 457783 ) on Friday April 01, 2005 @05:24PM (#12114799)
    Long sessions in front of CRTs produce eyestrain, apparently even at high refresh rates like 85Hz from what I read. No study to back this up though.

    But anyway the other problem is radiation. For the most part, the front is well shielded although some do leak out but the sides and back are not as good as the front. In some companies, as soon as someone is pregnant, their CRT is replaced with an LCD.

    Of course, in the long run, LCDs save a lot more energy and that's a good thing by itself.
  • CRT's are surely as healthy as radon.

    For more info on Radon Health Mines... and this is NOT an April Fools... visit here: html []

    Some of my inlaws are freaky-nutty suckers and go in for this crap.

  • I noticed that Bill Gates was one of the 1st people to do this

    If you're modeling your life after Bill Gates, you've got worse problems than LCDs over CRTs.
  • The government (and aliens) can monitor the radiation coming from your CRT and see what you're seeing on your monitor from far away...through walls.. []

  • by pyrrho ( 167252 )
    it's fine! don't worry!

    it's great to have millions of high speed electrons sprayed at your head all day!

    it's good for you.

    it gives your brain conditioning... like a nano-massage... and a tan, you're brain gets a tan.

    Also really good? letting a pitching machine hurl baseballs at your face.
  • by merlin_jim ( 302773 ) <James@McCracken.stratapult@com> on Friday April 01, 2005 @05:28PM (#12114847)
    First off, the human vision system was made to look at diffuse light sources; that is we're meant to look at things that are reflecting light, not emitting it. There are some strains from that. And especially from vivid colors side by side. I once saw someone with the apple color scheme - green on red. Instant migraine.

    More worrisome, the x-rays being emitted out the front are carefully regulated for health reasons. However this doesn't apply to the back, which typically has 3-7 times as much radiation coming out of it. Lots of offices are setup in such a way that you are staring directly at the back of a co-workers monitor. So, your three CRT setup?

    Should be perfectly safe. For you.
  • In addition to being easier on the eyes (the refresh rate is a big plus), LCDs save power. I have heard of companies replacing CRTs with LCDs to lower the total cost of ownership. In addition to taking less power every day, there's less heat generated requiring less air conditioning which in turn takes even less power.
  • many government offices switched to the much more expensive LCD's - despite budget cuts and having to go with the lowest bidder strategy they operate under. Was this ONLY for style and space savings?

    They cost less in the end because they are so more energy efficient. This will save money in the end because of the drop in power consumption and thus power bills. When you have about 500 lcd monitors they are probably going to use less energy than 250 CRTs.
  • but your retinas are probably so fried by now you would no be able to read it. I will email a copy to your seeing eye dog/pony.
  • No need for conspiracy theories ;-), the math alone is simple enough: Take a typical corporate or federal office building with a few thousand desktops, compute the space & power saved directly by each CRT replaced with an LCD, and indirectly by the load on power lines, UPS back-up systems & air conditioning (we're not talking one CRT, but several dozen floors full of them), sum it all up and add the savings they'll get from their insurers if they tell them there's not much left to implode - all of t
  • by digitalgimpus ( 468277 ) on Friday April 01, 2005 @05:34PM (#12114908) Homepage
    In places where electricity isn't cheap (such as cities)... it's cost effective to upgrade to LCD.

    They have a higher up front cost, but when used 40hrs a week (and many employees leave computers on 24x7 with a screensaver)... the savings in electrical consumption make up for the cost (some say as little as a year, some say about 2 years).

    When you have a larger company with 500-1000 computers, each with a display... if you can cut 1000 units down 50%... that's a considerable savings.

    Some companies during the blackouts in CA pushed laptops. Not only did it encourage people to do a little work on weekends... but it cut down on power consumption in the office.

    A display can last through several CPU's. The technology doesn't change that fast. Unless your a graphic artist it's irrelevent. A 7 year old 19" CRT is just as good as one bought today if it's taken care of. For most users the really subtle differences don't matter. By an LCD today, and your investing in the next several years. Get one with DVI/VGA input, and your in good shape for most users. Just swap out the CPU's every so often.

    It's not just about space savings. It's cost savings.

    The other thing to note is that CRT's contain a few pounds of Lead, mercury, and other hazardous materials. Several states have (or are proposing) disposal taxes for CRT's. So in the future throwing one out may cost you some cash. IT departments are well aware of this. Throwing out 1000 CRT's at $50 a pop.. that's $50,000 in additional costs.

    I wrote a paper that discusses this a bit last year for an Environmental Biology course (incorporating my Business MIS studies). You can find that here []. It discusses the environmental impacts of the CRT among other problems. LCD's aren't perfect, but they are much better.
  • EVERYONE seems to be switching to LCD's - I noticed that Bill Gates was one of the 1st people to do this, even when the cost was super high

    And man he had to save his pennies! Poor Guy!

  • This doesn't seem to bother most people I talk to, but I can actually see the refresh rate on CRTs. I refuse to work with anything less than 85Hz. 60Hz and a white background make my eyes water.

    LCDs on the other hand are still slow enough that they look constant to me. Even at the 60Hz they run at. They even look more constant than a CRT at 100Hz. The only LCD I've seen that I can see refresh is a ginormous IBM LCD with some ungodly resolution.

    Just go to a best buy and look at the LCDs and CRTs that they
  • Even? (Score:2, Funny)

    by nottsp1 ( 854247 )
    I noticed that Bill Gates was one of the 1st people to do this, even when the cost was super high

    I bet it was beans on toast for the Gates' following that spending ludicrousy...

  • I don't know about everyone else, but I switched from CRTs to other technologies (LCD, DLP) as fast as I could not because LCDs and whatnot are smaller (although that was nice) but because they don't flicker and are very sharp in comparison.

    Unfortunately my employer has found a source of LCD panels that are blurry, but at least they don't flicker.

    • Most color DLPs flicker, because of the color wheel. I'm sure there are some that use 3 projectors instead, though.

      Most LCD panels can not be blurry, because the individual pixels are actually electrodes drawn on the inside of the glass with conductive material. I'm sure it would be possible to make an LCD panel that would be blurry on purpose, but naturally they have perfect geometry and focus. Your employer must've had to work hard to find a source of LCD panels that are blurry. Would you care to tel
    • jimfrost wrote:

      Unfortunately my employer has found a source of LCD panels that are blurry, but at least they don't flicker.

      This isn't hard to do. Low end LCD manufacturers are buying the LCD's that fail the quality assurance of the big name manufacturers. They get them for dirt cheap because of issues with dead pixels, focus problems, or glare coating unevenness. There is a market for these screens (be it a bundle or bulk purchase) where the cost is the driving factor rather than quality of the display.

  • The question of whether CRTs pose a health risk is extremely controversial.

    Those that think they do attribute the risk to the low-frequency magnetic fields created by the deflection yokes. The risk was considered serious enough for European countries to regulate magnetic field strength, and almost all modern CRTs are built to meet these European standards and contain shielding. (Similarly, the glass CRT envelope contains enough lead to shield against X-rays, which once were a concern in home television set
  • Dunno about health effects on the eyes; I bought a 17" LCD because lugging the CRT to LAN parties was killing my back.

    The eye strain factor seems about the same for me. Your mileage may vary. I *like* my LCD better; it seems crisper, but the CRT is getting long in the tooth.

  • Whgen viewing/working for long periods of time, CRTs used to give me headaches. Ever since I switched to LCDs, that has gone away. I am much happier with the LCDs too. I will never consider using CRT again.
  • It has been 6 years since I've been using a laptop, and I noticed a consistent worsening for my eye sight (with a mix of myopia and astigmatism). Before that, I used desktop computers with CRT monitor with no problems. It turns out that using a laptop is bad too in the sense that you're looking at the screen much closer, since the keyboard is right under the screen. Nowadays I use an usb keyboard for my laptop whenever possible. With the external keyboard, I get at least an additional 30cm between my eyes a
  • no (Score:4, Informative)

    by adminispheroid ( 554101 ) on Friday April 01, 2005 @05:51PM (#12115176)
    I guess I can't resist giving this a serious answer. The one plausible radiation hazard from CRTs is x-rays. The electron beam is typically 10-20 kilovolts, which means it has the potential to produce 10-20 Kev x-rays. This made the original color TVs a serious health hazard. Since then, improvements in the phosphor have made it possible to decrease both the beam energy and the beam current; and I believe they've put more lead in the glass. I don't hear anybody saying there's an x-ray hazard from modern TVs and monitors, as you did decades ago. But that would be the concern.

    About the 60 Hz and 10-100 KHz sweep and the dot clock and all of that -- professional fear mongers bring this stuff up all the time, but there is neither any plausible mechanism nor any experimental evidence of any danger from this stuff. In particular, for a photon to carry enough energy to damage DNA it needs to be at least in the shorter UV -- this is the mechanism by which UV, x-rays, and gamma rays cause cancer.

  • Seems like a lot of government offices are switching to LCD monitors because they save desk space.

    The local community college admissions and records office are using 15" LCD monitors with a compact micro-ATX case for data entry to replace the clunky CRT with build-in keyboard. Unfortunately, the backend is a mainframe computer that communicates over serial lines. The processing time is still slow today as it was 15 years ago when I was getting my General Ed degree. Go figure.
  • I am also concened about the effects of long-term exposure to CRTs and spent some time researching on the net, finding no conlcusive evidence either way about X-rays.

    However I also read a swedish study that concluded spending a long time in front of CRT's (especially big ones) may cause problems if you have metal dental work such as amalgam fillings, due to them inducting a slight current from the CRT's EMF field.

    I've spent about 25 years of working in front of CRTs with no noticeable problem so far, exce
  • Don't worry (Score:4, Insightful)

    by groomed ( 202061 ) on Friday April 01, 2005 @05:58PM (#12115267)
    . I work in front of typically 3, 19" CRT's for 12 - 16 hours per day at an average distance of 18". Can these magnetic fields cause Leukemia, or anything else?

    Don't worry, you'll probably die of a heart attack long before the leukemia kills you.
  • by CaptainCarrot ( 84625 ) on Friday April 01, 2005 @06:00PM (#12115285)
    Of course they're dangerous. They also suck down massive amounts of power. Between that and the heat they put out, stressing a building's HVAC system something fierce, flat panel displays pay for themselves in energy savings in a year or so.

    That's one reason government agencies switched, but there are other factors. As is well-known from such classic scientific research milestones as the G-bomb, the first private venture into space using insufficient spacecraft shielding, or poisoning by spiders exposed to ionizing radiation, the kind of hazardous rays that CRTs emit (especially from the back) have been known to induce superpowers in humans. Since the extent and strength of these powers are not predictable, the government is doing everything it can to avoid having them bestowed on listless, apathetic bureaucrats.

    Bill Gates acquired superpowers years ago, of course, so he got rid of his CRT because he no longer needed the radiation. His power? He attracts money. The whole Microsoft thing is just a front to keep his power from public view so he can just exercise it over the normal course of the day. (And a good thing too. Can you imagine him in spandex?)

    For true powers-seeking geeks, of course, the best course of action is to surround yourself with as many CRTs as possible. Gaming and graphic hardware companies know this, and since geeks are their main customer base both industries have been working toward their empowerment for quite some time now. This is the real reason for nVidia's TwinView technology, for example, and also the real reason why games are not developed for Linux necessitating a Windows box sitting next to the useful one. (After all, the more boxes you have in your house, the more CRTs you have pumping out those healthful X-rays.) It's no coincidence that most games involve the exercise of some kind of superhuman ability: they're trainers.

    Sure, there's a serious risk of contracting some kind of cancer here, but considering the potential gains a cost/benefit analysis clearly favors bathing yourself in that wonderful blue glow.

  • by WaterDamage ( 719017 ) on Friday April 01, 2005 @06:03PM (#12115327)
    I've switched to LCDs as soon as I could get my hands on them and I've been feeling better since the move. I'm one of those very sensitive people where if I keep a cell phone longer than 5 minutes next to my ear I get a headache and my ear starts to hurt but not if I use a headphone. I happen to work in a hospital and whenever I pass through the radiology rooms I instantly get dizzy and feel like passing out in less than 5-10 of being in them. This is not a phobia, I'm not afraid of them, but my body picks up and feels the extremely strong presence of radiation even when the equipment is not in use.
    I have been using CRTs very heavily in the 80's and have noticed that my vision deteriorated extensively in less than a year of serious usage (8+ hours a day) so I believe there may be a strong correlation there. Also, I'm sure that all the x-ray radiation emitted by the CRTs over your lifetime will potentially have a negative effect on your body so don't be surprised if you end up with some weird tumor or mysteriously die! I can't even think of a single positive thing (health wise) about CRTs, if you can, I definitely would love to hear about it! The real question now is, ARE LCDs safe? Given how sensitive I am I think not since I have yet to encounter any negative symptoms from heavy LCD usage.

    Time to call an attorney and start a class action suite to sue those damn CRTs companies for causing my vision loss and the thousands I've spent on glasses and contacts over the years. I know I'm not the only one here!

e-credibility: the non-guaranteeable likelihood that the electronic data you're seeing is genuine rather than somebody's made-up crap. - Karl Lehenbauer