Electroluminescent Display aging - Was : Re: Flat panel display rot - "tunnel vision" in electroluminescent and other displays- bad seals. - test-drb@ccmp.vtda.org

25 Oct 2016

Update: I've swapped the displays and drivers around, and the "tunnel"
effect seems to be a property of the panel and not drive electronics.
Perhaps they are all high-hour examples?

Anyone here an electroluminescent display expert?

...

 On Wednesday, July 20, 2016, Ian Finder <ian.finder at gmail.com> wrote:

  No, I'm not convinced the EL repro isn't
a driver electronics issue.

 I'm just a little confused about why the issue congregates at the edges
 of the displays. Any ideas why that might be?

 I may try swapping the panels around this evening if I am feeling brave.

 On Wednesday, July 20, 2016, Brent Hilpert <hilpert at cs.ubc.ca> wrote:

  On 2016-Jul-20, at 12:52 PM, Ian Finder wrote:

  I have a few GRiD compass systems and some are
suffering from massively
 decreased contrast on the edges of the displays:

 [See the system on the left]
 https://www.instagram.com/p/BIGGzUzgat-/?taken-by=tr1nitr0n

 [Or this one:]
 http://www.ripstick.com/USCM/images/Grid_Compass_1101_  Laptop_in_Box_002.jpg

 Meanwhile, other EL systems I have- like my HP integral PC- haven't
 succumbed to this.

 I have seen similar issues on amLCD displays in my Tadpole, Toshiba and
 other machines, so this is something we all may have to confront.

 -------

 I was wondering if the folks here had theories?

 I'm thinking moisture (or air) might be leaking in from the edges of  the
  glass panes, perhaps from a compromised seal-
sorry for the silly  picture
  but you can see the composition of the display
here:

 https://www.instagram.com/p/6BXaLBtSzd/?taken-by=tr1nitr0n

 Does anyone know how one might prevent this from progressing- storage  tips?

 Could it be reversed?

 Better yet, does anyone have ideas on how to rapidly dehydrate the  display?
  Perhaps there is even a way to re-seal them.

 I think all two-glass-pane displays that don't have a vacuum may  eventually
  succumb to this.

 Perhaps it is just oxidation and not moisture, but I'd love to hear any
 theories. 

 Are you convinced this is a panel problem rather than a driver
 electronics problem?

 In one picture it looks like the sort of thing that happens when you
 have to turn up the brightness (for some types of display), resulting in
 partial illumination in other areas of the screen.

 I've never had opportunity to repair or work on EL flat-panel displays,
 I'm not familiar with the driving techniques and requirements, so this is
 just a query/guess. (I see it's an X/Y matrix drive scheme, but the
 voltages & timing & phasing I don't know about.)

 --
    Ian Finder
    (206) 395-MIPS
    ian.finder at gmail.com

 --
    Ian Finder
    (206) 395-MIPS
    ian.finder at gmail.com

-- 
   Ian Finder
   (206) 395-MIPS
   ian.finder at gmail.com