Failures in antiglare coating on CRTs?

I have seen on some monitors where the anti glare started to degrade. The most common cause was during the coarse of its history, the screen has been cleaned with a strong glass cleaner, especially one that contains ammonia, or alcohol. Some types of anti glare coatings can be effected if the monitor was kept in a humid environment.

As for getting shocks from the front of the CRT, check to see if the CRT rear wall surface is properly grounded, and that the shield around it is also properly grounded. Glass is normaly not conductive, therefore the effect you are getting is from a dielectric pickup effect.

--

JANA _____

The only thing the CRT has ever been cleaned with is a microfibre cloth and filtered water ("filtered" as in "gone through a ceramic/activated carbon 'pure water' filter"). On one occasion shortly after I got the monitor, I used a CRT cleaning cloth (basically distilled water and a neutral detergent on a microfibre pad) but that's it.

I had a Samsung Syncmaster 3 before the Mitsubishi, treated them the same way and never had any issues with the coating - the Samsung is now nearly eleven years old, the contrast pot is pretty much worn out, but the CRT is still as bright as ever...

I'm at a loss to explain this, and the only answer I managed to get out of NEC-Mitsubishi (well, NEC Display Systems) was - in effect - "it's your fault, you can only cause that if you use chemicals to clean it."

I've also noticed that the CRT seems to have started picking up a very nasty level of static charge - to the point where if my hand goes within a quarter inch or so of the CRT (as it does when I switch it off), I get a static-shock that's severe enough to cause my entire arm to spring backwards. Is this likely to be related to the failure of the coating?

Can anyone shed some light on this annoying little issue?

Thanks.

-- Phil. | Kitsune: Acorn RiscPC SA202 64M+6G ViewFinder snipped-for-privacy@despammed.com (valid!)| Cheetah: Athlon64 3200+ A8VDeluxeV2

512M+100G | Tiger: Toshiba SatPro4600 Celeron700 256M+40G No software patents! /

Polymer anti-glare coatings degrade fairly rapidly when subjected to direct sunlight or any other source of UV...such as florescent lamps or quartz-halogen lamps. Some, but not all, anti-glare coatings are also sufficiently conductive as to bleed-off the perfectly normal HV (static) charge CRTs collect. After all, you are blasting 25-30 kV at a non-conductive glass fishbowl. Try wiping the CRT with a sheet of anti-static material intended for use in clothing dryers...wipe it on you chair as well. Or spray it with "Static Guard" or something similar. It is also possible that the glass from which your CRT is blown does not have its full compliment of lead. If not, it has been showering its front surface with X-Rays, thus degrading the anti-glare coating (and your chances for a long line of descendents).

If you're worried, invest in an LCD monitor.

Well bugger, that's probably what's done it. The monitor is at a 45-degree angle to a window, and the evening sun usually hits it full-on (except when I close the curtains, for obvious reasons).

Interesting that the same treatment didn't kill the SyncMaster. Are LCDs susceptible to this problem as well?

It does say "keep the monitor at a 90-degree angle to light sources to prevent reflections" in the manual, but there's nothing about the antiglare coating, besides the usual massive list of chemicals to avoid using on it.

Will do - thanks for the suggestion.

Possible, but highly unlikely.

I might, but not until the Mitsubishi either dies or decides to go silly on me. Anyone know of any good brands of LCD? I was thinking along the lines of Samsung, or maybe Sony if someone throws a huge bag of money my way...

Thanks.

--
Phil.                         | Kitsune: Acorn RiscPC SA202 64M+6G ViewFinder
philpem@despammed.com (valid!)| Cheetah: Athlon64 3200+ A8VDeluxeV2 512M+100G
http://www.philpem.me.uk/     | Tiger: Toshiba SatPro4600 Celeron700 256M+40G
No software patents!            /

Hi!

Since they aren't coated in the same way that CRTs are, I'd tend to think the answer is no. However, the topmost layer of the screen is usually plastic and could melt if the sun got hot enough. I think it would take hours of very bright direct sunlight before that ever happened.

I'm a big fan of the Samsung display panels. I have ones from 15 to 19 inches in size. All of them have been great so far, with good brightness and sharpness. They are also reasonably priced. Despite somewhat heavy use, none of them have failed early on and only one was dead in the box. Samsung replaced it promptly.

The one Viewsonic panel I have puts off a great display. It's not quite as bright as the Samsung panels, but it works. I also have an AOC (cheap!) display panel. It is nice looking, and the picture quality is certainly usable, but the backlighting is not uniform and never has been.

William

Sounds like Samsung are still making monitors then. Only problem is none of my regular suppliers stock them :(

I'm not a fan of ultra-bright monitors. Heck, I run my laptop's TFT at minimum brightness, and the CRT at not much more than 30%.

Like I said, I tend to shy away from the cheapies because they're usually not much good (and the warranties tend to be along the lines of "send it back to our factory in Shenzhen and wait four months for a replacement").

Thanks.

--
Phil.                         | Kitsune: Acorn RiscPC SA202 64M+6G ViewFinder
philpem@despammed.com (valid!)| Cheetah: Athlon64 3200+ A8VDeluxeV2 512M+100G
http://www.philpem.me.uk/     | Tiger: Toshiba SatPro4600 Celeron700 256M+40G
No software patents!            /

I'd be more worried about the color filters in the LCD fading in the sun, everything else seems to.

That`s exactly the same as my Diamond Pro 740SB morning sun just clips the lower corner of the screen, and there is a patch of the coating missing right there. I must admit though, to one or twice cleaning the screen with isopropanol

Ron(UK)