Do LCD sets age and change colour?

[Alastair E]

Ive an oldish Thomson 28" set that was dead, now fixed, but has a greenish picture.

Ive heard that the UV the backlight tubes develop eventually destroy the dyes in the LCD panel causing colour shifts....

Is this a true fault or just a myth....?

Can this sort of fault be adjusted out a little--for a while?

Thanks.

[tom66]

Re: Do LCD sets age and change colour?

Myth. Unless the panel is a piece of junk. It can be adjusted check TINT or COLOUR control; service menu may have Gain/Offset control for each channel.

The tubes do go pink as they age on cold starts, but they usually return to white once warmed up, this is due to the mercury not being fully dispersed in the tube.

[Alastair E]

Re: Do LCD sets age and change colour?

Cheers Tom, Thats great info to remember...

Maybe I can rob some backlight tubes from a more recent heap of junk and freshen it up a bit! I ran it for an hour or so, but the colour seemed much the same.

This set I rather fancy as its still reasonably stylish and is pretty well-made in comparison to some of the crap you see!

I'll see if I can access the service-menu somehow. I don't have the correct remote--so that could be fun!

[leonard]

Re: Do LCD sets age and change colour?

what can happen is the heat from the ccfl lamps and the screen in some cases, make the plastic that covers the front of the lcd screen go discoloured in patches across the screen. you will notice this on a white screen,
also the lamps do go dull after a lot of use, you just have to look at an old laptop and put it beside a new one with a similar screen type

[Alastair E]

Re: Do LCD sets age and change colour?

Well--Here's an update.

It was the backlight-box and CCFL tubes.

I recently scrapped a Sharp set with cracked panel that had exactly the same backlight/LCD/T-Con board.

I changed over the backlight-box complete with CCFL tubes and lamp driver board.

The set is transformed--Perfect picture grey-scale and colour rendering--Looks brighter too....

The old backlight box did have a discoloured diffuser, but this wasnt the actual cause of the poor grey-scale, as I tried a different one from a 32" cut down, although wouldn't of helped.

It was the CCFL tubes that had gone yellow in their light output....