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Health Consequences of CRT Monitors?
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?"
"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.
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.
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 in a maze of twisted little posts, all alike.