Dim LCD display.

[JBUK]

I have a couple of T2Xs with what I describe as a dim looking yellow tinged display.
Having amassed a collection of backlights rescued from cracked screens I set about trying to cure them.
The first had actually failed and had no visible backlight. This was a Samsung LCD. I fitted another backlight. Not too difficult a job with this make and tested it. It was not noticably less yellow, certainly a bit brighter but had those shadowy areas that spread up from the bottom of the display. It also had several very bright areas along the task bar area. Where I presume light was leaking. I could alter the bright areas by applying pressure and or flexing but the shadows did not respond to this treatment.
The backlight location cradle is very poorly supported and difficult to locate it firmly on the base of the LCD compared with other makes and despite several attempts at reinstalling it I could not get a better display. It is of course useable but not one of those satisfying screens with a good bright white even display over 100% of the display.

So I turned to a Hyundai with a very yellow tinge. I fitted another backlight but noticed no difference. Same with another inverter.
Taking out the backlight I noticed that the bottom edge of the rearmost part of the LCD assembly - an acrylic type sheet that conducts the light up and away all over the back of the screen - was showing signs of cooking. It was badly yellowed especially at the ends.
Great find I thought. I fitted a replacement sheet from another cracked LCD which showed no signs of discoloring.
There was no difference. So I then fitted a brand new backlight and another inverter and signal cable. Waste of time too.

My conclusion is that there must be some deterioration of the rest of the LCD. Maybe the oil filled outer sandwich or perhaps one or both of the other two layers which contain the circuitry. The backlight does produce a lot of heat and it is maybe something to do with this which could cause the loss of whiteness and the fading.

Thoughts ?

[tfflivemb2]

I have seen several posts that suggest that a smoking environment, as well as excess sunlight can damage the outer layer of the LCD panel.