LCD vs. CRT in terms of eye health?

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repeatx3

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My vision has been deteriorating over the years and I have always used a CRT. Now, I am thinking about switching to an LCD because of numerous reports and opinions of significantly reduced eye strain. My question is, is the change from CRT to LCD so noticeable in terms of eye health to justify the higher prices of the flat panels? I would really like to keep my vision and have it change as little as possible. Thanks for your time [H]
 
It is exacly the question i need an answer too.

Im working in front of an LCD 9hours per day, and my CRT at home does not hurt my eyes, but i loose my vision years after years, and im only 17 holy shit!
 
Yeah, same here. I'm 18, I don't even notice eye strain from the CRT but if it is a factor in the deterioration of my vision, I wouldn't hesitate to change.
 
:D I'm 20, spend all day in front of my CRT.. my moniter sucks and my eyes hurt all the time :D

*takes of glasses for a second*

:eek: Holy sh*t!!!! I'm blind!!!!!! :eek:
 
Don't know any of the scientific mumbo jumbo in regards to this question... but I will just throw in my observations. For me personally, it goes something like this...

CRT @ <85Hz = eye strain
CRT w/ any alignment problems (blur) = eye strain
CRT or LCD w/o breaks throughout the day = eye strain
CRT or LCD w/ brightness set too high (never over 50 IMO) = eye strain

I prefer LCD, but I use both. 21" CRT's at 85Hz, and LCD's from 15" on up. All have low brightness settings if I can help it. I personally believe I get less eye strain from LCD's, but that's just subjective opinion. Either way, your best bet is to just give your eyes a rest now and again through the day. :)
 
repeatx3 said:
My vision has been deteriorating over the years and I have always used a CRT. Now, I am thinking about switching to an LCD because of numerous reports and opinions of significantly reduced eye strain. My question is, is the change from CRT to LCD so noticeable in terms of eye health to justify the higher prices of the flat panels? I would really like to keep my vision and have it change as little as possible. Thanks for your time [H]
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I started This Thread about CRT's and Radiation a few days ago. Quite a controversy, i'd say.

That said, i just bought my wife a LCD and I'm lookinga t replacing my 21" sony CRT as soon as I can decide on WHAT LCD TO FREAKIN' BUY. LOL.
 
Somebody feel free to correct me if I'm wrong, but I believe that LCD's don't use a typical "refresh rate" like a CRT would. Low refresh rates are what will irritate your eyes and possibly hurt vision. If you wanna double check that, take a camcorder and video tape a CRT, then video tape an LCD. You should see scanning lines moving through the CRT while the LCD should remain a solid picture. Hope this helps.
 
There are a few studies out there you can google fish for and most of them are biased towards the funder. If it is an LCD company it favors LCDs and if it is a CRT company it favors CRTs. Here is what I know from working in the industry for 10 years.

CRTs are addative light. That is the color production is actually creating energy. The electron beam ignites the phosphor and makes energy in the form of colored light.LCDs are subtractive light. The light source is a Flourenscent light passed through a defuser the passed through a colored filter. Then the only eneregy that is left is that of the filter is used. Subtractive light is much easier on the eyes and you suffer no EMF radiation.

LCDs are inherently brighter than CRTs so I would say that a good deal of the problems that exist are from having the brightness turned up to hi. Kudos to you canislupy for pointing that out. You were right on the money.

LCDs also don't have any flicker. They are a persistant device. When a color is activated on the screen it doesn't need to be reactivated to keep that color there. It only needs to be re-actived to change to a different color. The lack of flicker will help your vision tremendously. There is some thing called cognative correction. It is the assembly of flicker in your mind to produce a static picture. Most people don't see flicker beyond 85Hz but your eyes and brain still do you are just using brain power to assemble them. That causes a good deal of strain.

All in all LCDs are much better for your eyes and much easier on them. They are not with out their faults though. I read a report a while back that LCDs for some reason limit the amount of blinks per minute. Literally you actually blink less using an LCD over a CRT. The report didn't really go into why but that they had done hard counts and LCD users blinked half as much as CRT users. My guess is it is from the additive light, but who knows. The report did say that if you blink more while using your computer you will suffer much less eye strain and future eye problems.

Hope that wasn't too out there. Just reporting what I hear and read.

SDM
 
EM radiation emitted with LCDs and CRTs is the same: only light (the visible part of the EM spectrum) leaves the front of either type of display. X-rays and other forms of EM radiation haven't been a problem with CRTs since the 80s.

Eye-strain can be invariably traced back to poorly configured monitors and disregard for or ignorance of the need to take frequent breaks. Low refresh-rates, high brightness levels, moire, offset color levels, etc., all things which are easily corrected, but seldom done.

It is recommended to look away from the display at least every 20 minutes. Look around the room, or outside. Just allow your eyes to focus on something other than the display in front of you. Every two hours you should take a longer break of 15-30 minutes.

It's utter nonsense to state that either LCDs or CRTs by default induce more eye-strain. It's only that it is far more easy to improperly configure an CRT's image.

Naturally, poor quality displays will never have a good image, so choosing a display from a good manufacturer and reading reviews on it which reflect on its IQ before deciding to buy it will certainly help to take the first step towards preventing eye-strain (the second being properly configuring its image settings).
 
blinking helps the eye? bullsh*t

I blink alot!!!! not only in front of the screen, I was once accused of trying to be cute to get out of trouble because of my normal blinking...believe it or not I blink about 1-2.5 times a second...

and I am blind as a bat
 
Being someone thats been thru eye surgery twice for torn retinas, and yeah my sight sucks now, my opthamalic surgeon said to switch to LCD. He told me what sonic death monkey pointed out, that even though you don't see flicker over 80mhz your brain still sees it and it can still cause strain. Probably not a big deal for someone with 20/20 that takes regular breaks but if your getting old or have vision problems, LCD is better.
 
round CRT < flat CRT < lcd

however. if you play games or watch video with high frame rates, crt wins b/c it rarely if ever ghosts/redshifts
 
Girl I work with has some kind of chronic problem with her eyes(slowly losing her vision, has a lot of operations, ect). Her Doctor said she should use nothing but an LCD screen.
 
Woofer thats not all true... I just got a samsung 172x a month ago and I have never noticed it ghost... I play bf:V ut2k4 cod etc... and I watch alot of movies on it as well
 
sh*t :mad: now I need to buy an LCD... there goes the car I wanted to buy this year :mad:
 
here's what i gather. lcd's hurt my eyes more because it isn't as bright as a crt, but its is a lot softer to the eye even't with the squinting. i would still wait till lcd's come down in price. also always have a lot of light so your not just staring at the screen, and if u have to squint u need a bigger crt or wait for an lcd.
 
IMHO, LCD's feel a lot better than a CRT. I went from CRT's to LCD's at home and work and it's easy to work longer. Not scientific but definitely worth getting LCD's to me.
 
I'd get an LCD in a heart beat. But not til i can get a 22"@1600x1200 for around $600. Til then I'm fine with my NEC 2141SB.
 
From personal experience (not quoted from any hard facts or numbers), I tend to get better sight quality from CRTs, but my eyes do get tired quicker (refresh rate probably).

LCDs have always been nice on my eyes.

To someone who said that LCDs aren't as bright as CRT - I can tell you my viewsonic 171b is plenty bright enough -- it's actually brigther than my CRT!! Took me a little of getting use to after I got the monitor.

On the issue of ghosting: from what I gather, it use to be a problem for LCDs. Nowadays, the newer LCDs rarely have a ghosting problem. I know for my LCD, I have NEVER noticed it ghost before.

Of course, check reviews of specific monitor when you're looking to purchase :)
 
I switched to an LCD in about October. Since then, my perscription has not really changed. But, when using a CRT for 9 months, I'd be getting new lenses. That's my experience.
 
After I got my LCD I been getting headaches from my old Gateway2000 CRT :(
 
It's great hearing everyone's thoughts on the subject, but I don't think there is much more that needs to be said at this point. It should be pretty well-established by now that LCDs are for the many reasons given above better for your eyes than CRTs. Of course I have a 2141SB, so I will say right now that I am guilty of not heeding my own advice :p
 
Synful Serenity said:
It's great hearing everyone's thoughts on the subject, but I don't think there is much more that needs to be said at this point. It should be pretty well-established by now that LCDs are for the many reasons given above better for your eyes than CRTs. Of course I have a 2141SB, so I will say right now that I am guilty of not heeding my own advice :p
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Actually, no reasons were provided why LCDs are supposedly better than CRTs. Only observations were made, all of which can be explained by the simple fact that CRTs are harder to configure correctly compared to LCDs.

A good and [/i]properly configured[/i] CRT makes even the most expensive LCD look like a POS.
 
I went from using a CRT since 1994 to an LCD just now in 2004. My eyes hurt a lot less and they don't get red or irritated after long hours of use. Everything is also much sharper and clear. I can't believe what a difference it makes, the only thing that had kept me away was price. So just from my personal experience, LCD's are much easier on the eyes.

I think the biggest advantage of an LCD is the sharpness. CRT's are always blurrier when compared side to side with an LCD.

I was using an IBM P260 FD trinitron running it from a G400, then G450 then G550. It was sharp and all, but after I compared to my Dell 2001FP running via DVI from the ATi FireGL x1, it is truly no comparison. People that have actually spend time using an LCD will testify to the clarity of the image and reduced to non-existent eye strain. Give LCD's a try with a DVI connection and I swear you will NOT go back to CRT.
 
though you don't see flicker over 80mhz your brain still sees it and it can still cause strain.
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But why? If it is above 85Hz, since your eyes can't see it, why and how would the brain see it?

As well, what's the contrast ratio that is acceptable? Does it has to be 500:1 or can 400:1 do?

As to comparing CRT vs. LCD, it is possible that with CRT, even today's Sony variable Aperture Grill Pitch CRT, its gun is firing very nicely at the center, but not as sharp at the corner, which is why even w/ the best CRT, you'll get 0.23 at the centre, but 0.27 AGP at the corner. And 0.27 at the corner is blur to me.

As well, even w/ the best CRT, there is Low Freq. radiation and Very Low Freq. radiation, and with today's by law, we have no control over how low the radiation is. So a half decent brand name can claim "Very low emission" but it is meaningless. It could turn out to be rather high radiation. Those radiation, long term facing the monitor can be harmful to your brain and your eyes.

With good brand name, like Viewsonic or Sony, when they said "low radiation", they really meant it, but there is still radiation. Low is not equal to No. So, even at low radiation, eventually it will get to you. With LCD, there is no radiation so you don't need to worry about it.
 
Elledan said:
Actually, no reasons were provided why LCDs are supposedly better than CRTs.
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I never said they were. I said they were better for your eye health. The fact LCDs are better for eye health does not determine LCDs being "better" than CRTs...I told you I have a 2141sb because I like being able to have 85 blur-free frames per second at 2048 x 1536, so this is not an endorsement for LCDs. But as I said, the reasons why LCDs are better for eye health have already been said so there's no need for me to repeat them.
 
Synful Serenity said:
I never said they were. I said they were better for your eye health. The fact LCDs are better for eye health does not determine LCDs being "better" than CRTs...I told you I have a 2141sb because I like being able to have 85 blur-free frames per second at 2048 x 1536, so this is not an endorsement for LCDs. But as I said, the reasons why LCDs are better for eye health have already been said so there's no need for me to repeat them.
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You're not making any sense.

Whether or not a display affects eye health depends solely on the amount of eye strain caused by the display and environmental factors (lighting, glare, etc.).

If you are certain that CRTs cause more eye strain compared to LCDs, then you're also saying that the image quality of CRTs is always worse than that of an LCD, but you then proceed to state the opposite of the previous statement, contradicting yourself.
 
Happy Hopping said:
But why? If it is above 85Hz, since your eyes can't see it, why and how would the brain see it?
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It is fiction, most people don't know how monitors actually worked, especially the so called experts.

As well, what's the contrast ratio that is acceptable? Does it has to be 500:1 or can 400:1 do?
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For human normal, 450:1 is at acceptable but only for the quality finicky, and 400:1 is at the edge of unacceptable.

As to comparing CRT vs. LCD, it is possible that with CRT, even today's Sony variable Aperture Grill Pitch CRT, its gun is firing very nicely at the center, but not as sharp at the corner, which is why even w/ the best CRT, you'll get 0.23 at the centre, but 0.27 AGP at the corner. And 0.27 at the corner is blur to me.
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Very true, short-neck, flat-screeen models are the worst.

As well, even w/ the best CRT, there is Low Freq. radiation and Very Low Freq. radiation, and with today's by law, we have no control over how low the radiation is. So a half decent brand name can claim "Very low emission" but it is meaningless. It could turn out to be rather high radiation. Those radiation, long term facing the monitor can be harmful to your brain and your eyes.

With good brand name, like Viewsonic or Sony, when they said "low radiation", they really meant it, but there is still radiation. Low is not equal to No. So, even at low radiation, eventually it will get to you. With LCD, there is no radiation so you don't need to worry about it.
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In the USA when it stated "Very low emission", it meant typical xray safety radiation measuring equipments couldn't even pick it up much less your skin. The glass in the front of the monitor is heavily leaded, the high voltage is never above 35Kv with extremely low current, there're models above 35Kv but few and 50Kv is about impossible to find, the Phosphor deposit is heavily optimized for visible-light energy.

All of which made for near zero xray radiation emission... as even when there's some near zero radiation, it is weak-xray (low-energy xray, low-ionizing xray) posing low-danger, and then still being low-energy, low-ionizing, it couldn't penetrate anything behind a 100Kv leaded-glass shield. The inch-thick leaded-glass shield is what made the tubes so damn front heavy.

You actually get greater exposure to radiation being outdoor than from sitting in front of a monitor. The earth natural radiation shield didn't do anywhere near as good a job as your monitor. If you ever get a chance, try comparing the xray measurements you get from the front of your monitor and the outside with the beautiful sun in the spring season.

Don't do it in summer, you may never wanted go outside ever again and prefering to sit in front of your monitor instead. :D
 
Elledan said:
Actually, no reasons were provided why LCDs are supposedly better than CRTs. Only observations were made, all of which can be explained by the simple fact that CRTs are harder to configure correctly compared to LCDs.

A good and [/i]properly configured[/i] CRT makes even the most expensive LCD look like a POS.
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Seems you missed the point of the discussion. Of course image quality is superior with a CRT (which is why I still have mine), but they do cause greater eye strain. I tried everything, lower res, higher refresh rates. None of it helped. The CRT, with its constant although imperceptible flickering, was giving me migraines. Much the same way the fluorescent tubes at the store my sister worked at were giving her migraines.

I used to get at least a couple migraines a week, but after getting an LCD and using it primarily (even with the CRT on but not focusing on it), I've only had a few migraines since Christmas. Not 3+ migraines a week.
 
You actually get greater exposure to radiation being outdoor than from sitting in front of a monitor. The earth natural radiation shield didn't do anywhere near as good a job as your monitor. If you ever get a chance, try comparing the xray measurements you get from the front of your monitor and the outside with the beautiful sun in the spring season.
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thx for the info. One more question, what about prolong use? Would there still be a reasonable radiation risk factor? I use my 20" Trinitron about 10 - 12 hr./day, 5 days/week, plus 5 - 6 hr per day on Sat. and Sun.
 
get a geiger counter and put it next to the monitor. Every click is a beta, gamma, or alpha particle hitting the counter. It is not much more than ambient radiation. Wow I actually used physics in RL :). As for the eye strain, I don't really know. Don't worry bout the radiation :)
 
Calibur said:
get a geiger counter and put it next to the monitor. Every click is a beta, gamma, or alpha particle hitting the counter. It is not much more than ambient radiation. Wow I actually used physics in RL :). As for the eye strain, I don't really know. Don't worry bout the radiation :)
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Yeah, the eyestrain doesn't really have anything to do with radiation. Different issues.

The truth is, not everyone is sensitive to the CRT's flickering. Maybe over time more will notice, but until it happens it's hard for someone to understand how frequent use of a CRT, even good ones set with optimal settings, can lead to a whole lot of frustration. It's kind of like describing clinical depression to people who think depression is just the occaisional bad day. They just don't get it, and since it doesn't happen to affect them they assume it must not exist.
 
Happy Hopping said:
thx for the info. One more question, what about prolong use? Would there still be a reasonable radiation risk factor? I use my 20" Trinitron about 10 - 12 hr./day, 5 days/week, plus 5 - 6 hr per day on Sat. and Sun.
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I don't know, I never did anything to know about prolong use to tell you. I can only give you my opinion of the radiation risk is that... I see no danger of radiation exposure to myself, prolong use or not and simply paid no thought to it.

Calibur said:
Wow I actually used physics in RL :)
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Ha ha... Now and then it is handy in real life :D, though often when actually used for answers, people will usually assume you are telling them theories instead of facts.
 
emorphien said:
The truth is, not everyone is sensitive to the CRT's flickering. Maybe over time more will notice, but until it happens it's hard for someone to understand how frequent use of a CRT, even good ones set with optimal settings, can lead to a whole lot of frustration. It's kind of like describing clinical depression to people who think depression is just the occaisional bad day. They just don't get it, and since it doesn't happen to affect them they assume it must not exist.
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The truth is, the problem do exist. Every normal person on earth have the problem with flickering, the difference is only in the degree of sensitivity.

You, myself, and others are more sensitive, people like us are usually also the ones that rarely able to withstand the strobe-light stop-motion effects which most others could.

But don't worry, the problem will lessen with age. As you get older you'll have slower neural responses, more light-rods in the back of your eyes get destroyed from natural radiation exposure over time or simply died-off... things will improve.

All of the above just meant you will have to buy good fluorescent lights instead of shitty ones, good CRTs instead of shitty ones.

For example -> the cold-cathode fluorescent tubes used for back-lighting in all new LCDs are perfectly fine for us to use. Typical old Plasma displays will give us problems, newer Plasma display models won't.
 
CRT's have always bugged my eyes. Borrowed a 17" Samsung LCD a year ago for a few months, and my eyes loved it. Went back to my new flat 17" CRT, and my eyes were getting bothered again. Bought the Samsung 173T a month ago, and my eyes loved it. Using a CRT right now since the LCD went in for RMA (scratched screen), and my eyes are bothered. Samsung is sending me a new 710T as a replacement, so I'm sure my eyes will be happy again. I use a 19" CRT at work, and my eyes always bug me. And yes, I always look away every 20 mins or so, take breaks, etc.

All the CRT's I've used in the past few years have been at 85 Hz. The amount of time I spent in front of a computer is very small compared to the time I spent outdoors, doing all sorts of activities (climbing, rappelling, biking, running, camping, shooting, etc). I wear glasses now (got them about a year ago) because I can't see clearly for very far. No glasses required at distances like between me and my monitor. Coincidence? No more CRT's for me.
 
RickyJ said:
The amount of time I spent in front of a computer is very small compared to the time I spent outdoors, doing all sorts of activities (climbing, rappelling, biking, running, camping, shooting, etc). I wear glasses now (got them about a year ago) because I can't see clearly for very far. No glasses required at distances like between me and my monitor. Coincidence?
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You're describing people liked us, we're born with faster neural responses than average, our eyes get strained from keeping up with responding to the light levels giving us headaches, our eyes tended to be over-worked from intense concentration, most of us become near-sighted even if we were not born that way. If nothing is wrong with our musculature system, we also tended to be the best athletes from having above average hand-eye coordination reflexes.
 
i am sitting here right now with the back of a computer monitor about 2 feet from the back of my head... is that bad radiation wise???
 
nam-ng said:
You're describing people liked us, we're born with faster neural responses than average, our eyes get strained from keeping up with responding to the light levels giving us headaches, our eyes tended to be over-worked from intense concentration, most of us become near-sighted even if we were not born that way. If nothing is wrong with our musculature system, we also tended to be the best athletes from having above average hand-eye coordination reflexes.
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Check. Us = win. :cool:

It's nice that glasses != loser anymore. Turns out we've been ahead of fashion. ;)
 
scott, no the monitor is pretty well shielded. Shouldn't expierience much more than normal radiation. Try putting a geiger up to someones stomach after an iodine test. That is safe, and the monitors emit much less radiation. Even if you do get hit by beta particles (electrons) they are easily stopped by the skin or a thin layer of clothes
 
my eyes seem to bug out lately and i asked my doctor if it was my computer screen (i got an lcd) he says its cause i play too much video games and i forget to blink. damn... you think i can sue the game company for that.... hehehehe then ill take the money and build a sick new rig.
 
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