lcd vs. crt lifespan

[rlemmon]

Hey guys, I was wandering do lcd monitors have a longer lifespan than crts ?

[Blanka]

Wandering or Wondering  ?

Guess not.
A CRT was at the end of its evolution and stayed roughly the same since the first LCD's were introduced. The phosphors age, but besides that, nothing much happens to those screens.
With an LCD you're buying a relative new product, that has new technology on the horizon to make todays products obsolete. Think LED backlights, OLED's, etc. Just looking at the lifetime, the LCD has its weakest part in the tube. This one has a life of 30000-50000 hours, and it will be 30% less bright if not broken completely by that time. With normal use, it will be 5-7 years lifespan. If you have an old working CRT now, it will be working if the LCD goes black. But with horrible quality by 2013 standards. Replacement of the light in LCD's will be hard, and probably ends up being a nice DIY project with bright white LEDs instead of replacing the not-made-anymore tubelight.

[rlemmon]

Thanks for the info blanka, very helpfull.   

[qrz]

relamping an LCD monitor isn't for the faint of heart . it IS major surgery.
if one is careful , and patient , it will restore the brilliance for a few more years....
and with an inverter repair/replacement at some point..

crt's are a vacuum tube . (based upon 100 yr old technology)
 electron emission usually drops ( weak tube) well before phosphor fatigue occurs.
depending on usage ( hrs of use ) , crt's can last decades

lots of stuff in r&d



qrz

[Ken Layton]

And don't forget that the new LCD monitors are being soldered with that lead-free crap. So naturally there will be much more solder related problems. Coupled with ALL surface mount parts makes most repairs economically unfeasible. So into the landfill it goes in just a couple of years.

At least with most CRT commercial arcade monitors, they use standard discrete ("thru-hole") parts commonly available and easy to solder. Plus they are built to be repaired not thrown away.

[grantspain]

the last two statements I totally agree with.
There was a shift to lcd for touchscreen and gambling machines in the u.k about 4 years ago,whilst i was there i had to repair/replace more lcd in one year than crt in 5 years

the external power supplies are a major cause of failure,followed by failing backlights and inverters
the major problem with this is the vast amount of different parts required,pretty much the only thing on a chassis that is unique to the model is the flyback transformer

[SavannahLion]

This one has a life of 30000-50000 hours, and it will be 30% less bright if not broken completely by that time. With normal use, it will be 5-7 years lifespan.

That change is pretty dramatic too. I have had my laptop for about three years and the backlight is noticeably weaker.

It irritates me that laptops don't exactly have a "turn off backlight" feature on demand. So those five day long compile and download sessions are starting to take their toll on the poor lamp

...ends up being a nice DIY project with bright white LEDs instead of replacing the not-made-anymore tubelight.

I've been thinking of that exact same thing. Or maybe a light sheet to for better distribution of the light.

[richms]

It irritates me that laptops don't exactly have a "turn off backlight" feature on demand. So those five day long compile and download sessions are starting to take their toll on the poor lamp

Closing the cover will turn the screen off on every laptop I have had.

[Blanka]

My LCD has 450cd/m2 maximum brightness, and it adjusts the brightness to the ambient light. Most of the time it is at 40% or so. If they made the brightness regulator smart, it compensates for aging, and it can stay the same brightness the whole lifespan.

[Level42]

I agree about the CRT vs. LCD. However the pure LED displays will make an end to the display loosing it's brightness plus it (at least in theory) could last "forever". But I'm sure the manufacturers won't let that happen....

The only LCD I have is the one on my Mac Mini.  I hope my CRT TV will last long enough to pass both LCD and Plasma based screens and get (O)LED's instead.

[Ummon]

I agree about the CRT vs. LCD. However the pure LED displays will make an end to the display loosing it's brightness plus it (at least in theory) could last "forever". But I'm sure the manufacturers won't let that happen....

Don't forget the 'CHEAP' part that keeps getting inserted in there, too.

[ahofle]

I agree about the CRT vs. LCD. However the pure LED displays will make an end to the display loosing it's brightness plus it (at least in theory) could last "forever". But I'm sure the manufacturers won't let that happen....

LEDs lose their brightness over time too.  I have an LED nightlight and it's about 1/2 as bright as it used to be, and it's only been a couple years.

If LEDs did not degrade, there would not be a need for products like this:
http://www.sourcesecurity.com/news/articles/co-289-ga.2606.html

"The optical output of a typical LED illuminator will degrade by up to 10 percent within the first few months of operation and continue to degrade during the operational life of the illuminator."

[Ummon]

I think that's at least one reason why they haven't really marketed them yet.

[MonMotha]

*CHEAP* LEDs dim substantially over their relatively short specified lifetime.  High quality LEDs do dim, but not nearly as much as CCFLs, and they are specified to last longer.  The problem is that major manufacturers assume (quite correctly) that Americans (especially those in the USA, but this applies to North America in general) shop almost entirely on price and, to a lesser degree, basic bullet points.  LED backlight is a basic bullet point.  10M hr backlight lifetime to 90% original brightness shows up on page 72 of the owner's manual in the specs that nobody ever reads.  Therefore, they put cheap LEDs in.

Any time you buy LEDs (or any electronic part, for that matter) be sure to consult the datasheet.  These parameters are usually spec'd.  Take any datasheet for a part "Made in China" or "Made in Taiwan" and from a company you've never heard of with some salt.  Most of these companies are honest and out to make you happy, but some will say anything to meet your needed specs, even if they can't deliver.

I've decided that just about everything these days is disposable.  Not because I want it to be.  Not because I specifically buy it to be.  Things are disposable simply because that's how they are built.  Long gone are the days when something was built to last 20 years.  Of course, think about how far LCD and even CRT display technology has come in 20 years.  Heck, think how far LCD display technology has come in 5 or even 2 years.  In 5+ years when that backlight finally starts to give out, will you care?  Chances are you'll be able to buy something roughly "10 times better" (a subjective measure, of course), for 1/10th the price.

I like LCDs.  My new TV is a LCD, though I'll admit to getting a very good deal on it.

All that said, I recently decided, perhaps against my better judgement, to upgrade my PC monitor.  I have a ~5.5 year old AG Neovo LCD.  This was an extremely high end model back when it was new with MSRP of $1000+.  19", 5:4, 1280x1024@75Hz (tough to find that in ANY modern PC LCD under 21"), S-IPS panel, and the CCFL backlight is still amazingly bright (I still use it on one notch above the lowest setting of consequence).  My new monitor is a used 22" 16:10 CRT.  We'll see how it works out.

[Ummon]

*CHEAP* LEDs dim substantially over their relatively short specified lifetime.  High quality LEDs do dim, but not nearly as much as CCFLs, and they are specified to last longer. 

Well, I meant the 'cheap' tagline as 'inexpensive but efficient'.

I've decided that just about everything these days is disposable. 

It should be. Nearly everything in nature is. We should be heading back in that direction.