Re: LCD Etching

["Mark Leuck" <m..leuck@xxxxxxxxxxx>]

"Bob La Londe" <usenet@xxxxxxxxxxxxxxxxx> wrote in message
news:1129739577.fac4a52918e79e6f90a37793f803362c@xxxxxxxxxxx
> "Frank Olson" <Please-use-the-email-links@xxxxxxxxxxxxxxxxxxxxxx> wrote in
> message news:emt5f.227604$oW2.63793@xxxxxxxxxxx
> >
> > "Bob La Londe" <usenet@xxxxxxxxxxxxxxxxx> wrote in message
> > news:1129678307.69d1c5a2e38157e857522be6b8aac170@xxxxxxxxxxx
> > >I did a video job a couple years ago where the customer insisted on
> buying
> > > their own LCD flat screen monitors.  I don't recall what brand they
> used,
> > > but they stared to suffer from etching almost immediately.  When I was
> > > looking into that I was told almost all LCD monitors will etch fairly
> > > quickly when used in that type of application.  Usually within days
and
> > > with
> > > some within hours the bright text will start to etch.
> > >
> > > I have a little ten inch Sharp LCD I have had for many years that I
use
> > > for
> > > a test monitor and occasionally for part of a loaner system when I
have
> to
> > > send a monitor off for repairs.  It has always had a great picture and
> has
> > > never shown any signs of etching even when operated on a fixed quad
> system
> > > for over six months.
> > >
> > > I have a customer who wants me to loop out and install a flat screen
for
> > > one
> > > of their cameras.  Naturally I thought of Sharp.
> > >
> > > As I flip through my TV catalog I notice that Sharp seems to have two
> > > lines.
> > > One is just Sharp and the other is Sharp Aquos.  Anybody have any
recent
> > > experience with either of these for fixed view CCTV applications
> regarding
> > > etching or lack thereof?
> >
> >
> > I've sold dozens of LCD monitors and never encountered "etching"...
What
> > the heck is it (what does it look like)??
>
> I had never experienced it before that job, but its pretty bizarre.  Since
I
> didn't supply the monitors I wasn't too worried about it.  Basically there
> are artifacts left on the screen.  The worst is where you get the bright
> imaging from the on screen text.
>
> When I looked into it I had two different LCD mfgs (probably relabelers)
> tell me it was common for that type application.
>
> I have only a handful of sites with LCD monitors (all Sharp) and I had
never
> encountered it before, but I like to do jobs, take the money, and not have
> to do any service on them or have to make excuses for poor performance.  I
> figured before supplying a flat screen for this customer I would ask
around
> again.

I'm with Frank on that as I've not seen it either, the reason a TV will etch
is due to the scanning of the photo-ray (whatever they call it) on a
phosporus (however they spell it) background which over time degrades. An
LED pixel I would think wouldn't do that. Otherwise wouldn't we see that on
keypads?