Are all LCD panels prone to delamination - Page 1
Forum section: electronics / projects

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 24, 2016, 12:11:27 am
content: in the same degree? My 5-10 year old LCD monitors eventually all became unusable due to delamination. But that's an anecdote.I am thinking of buying an old "professional" LCD video monitor for my vintage computing needs. These monitors take s-video, YUV, or RGB in NTSC-style, without the need for an external scaler. (ie less junk on the desk).They are already ten years old however, and pictures are rarely clear enough to diagnose that online. But some pictures do show something that looks like delamination:http://www.ebay.com/itm/Sony-LMD1420-14-LCD-Monitor-AS-IS/201348937599?_trksid=p5411.c100167.m2940&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140131123730%26meid%3Db4d363c20d1e411289f33c97801c370f%26pid%3D100167%26rk%3D2%26rkt%3D12%26sd%3D192049392415That weird haze could be it, or it could be an unfortunate lighting effect? Or a backlight failure?

author: apelly
author_rank: Unknown
timestamp: December 24, 2016, 12:35:48 am
content: I'veneverseen it. But I was a late adopter and I haven't got one that old.

author: wraper
author_rank: Unknown
timestamp: December 24, 2016, 01:50:19 am
content: Quote from: Alex Eisenhut on December 24, 2016, 12:11:27 amThat is certainly failure. Either backlight (probably due to the moisture) or LCD panel itself.

author: Rerouter
author_rank: Super Contributor
timestamp: December 24, 2016, 01:56:07 am
content: Still have a 2006 old 19" benq IPS LCD running strong (the backlight brightness has degraded) it certainly hasn't delaminated, or suffered from burn in, but i picked up the habit of letting the screen turn off after 30 minutes early on.

author: coppice
author_rank: Super Contributor
timestamp: December 24, 2016, 02:05:24 am
content: Delamination should be rare, but a gradual build up of dirt between the diffuser sheet and the LCD is common. If the airflow in the machine is just right there seems to be a strong tendency for dirt to get in their, and for many models its a pain to get the thing apart and clean it.

author: tautech
author_rank: Super Contributor
timestamp: December 24, 2016, 02:25:26 am
content: Quote from: Rerouter on December 24, 2016, 01:56:07 amI've got some old monitors too that do the same thing. Just in the process of replacing the caps in it that I was too lazy to do last time.Replacing most of the PSU PCB caps improved it some but not enough that you could leave it on all the time. This one's an AOC 19" 4:3 and it's pretty old.For Alex's problem, I've had one or two go hazy too, a Philips 20" 4:3 gone almost white and I looked for ideas as to what it was and thought it was a backlight problem but I remain unconvinced it is. Was pissed when it went as I'd scored a matching pair of them, both nowThe weather is pretty shitty here and those might get a looking at too.

author: tautech
author_rank: Super Contributor
timestamp: December 24, 2016, 05:48:15 am
content: Quote from: tautech on December 24, 2016, 02:25:26 amThe AOC's fixed.Interesting PSU, 2 rails supplied to the monitor PCB, one 12V, the other 5V.That's not interesting but the secondary side of the SMPS is; the 12V rectification was done with a TO-220 double diode and a few caps as per normal. However the 5V rail was rectified with a whopping big single axial diode. It had a C, L, C configuration and low ESR caps have been installed. Nearly 2 hrs running now and no smells yet.On to the next one.......the 24"16:9 or the 20" 4:3 ?