LCD display : fraying at the edges

… well not quite, but you can see what I mean:

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I unboxed this balance today … it’s been in storage for several years … plugged it in and found that not-so-delightful effect. It has been plugged-in for about an hour now: all seems to work as it should, but the display is a mess.

Any suggestions ?

Should I put it in the ‘fridge, or by the radiator ?

I can’t find a date for it, but I suspect it goes back to the early days of LCDs

… It has a useful range, and is an interesting piece of history

MichaelG.

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Ref. __ a related history, here:

https://www.shimadzu.com/an/products/analyzer-and-balances/balance/history/history4.html

Edited By Michael Gilligan on 19/01/2023 19:08:01

My missus drives my 1994 VW Golf and if left for a while it loses bits of the LCD display. Drying the car out (ie. a bit of time in the sun and actually driving it) bit usually restores the function. What you depict is a bit more. Put in a bag with a desicant perhaps?

Thanks, Dick … I hadn’t thought of humidity

I’m leaving it plugged-in, sitting under the radiator, overnight and will see if there’s any improvement tomorrow.

MichaelG.

By coincidence I looked at a old brick sized first generation mobile phone, I had taken out its set of NiCad cells years ago so they did not leak or damage the electronics. The LCD (with the phone unpowered) is total mess, its is blackened on all four edges but the rest of the display is a mass of black specks.

Your weighing scales (being quite old) might possibly incorporate a generic, rather than a custom LCD module. An image of it 'lit up' in operation would show whether it has just plain 7 segment characters or whether it has other annunciators. I suspect the former as the panel shows oz, g, net (nett?)

Ian P

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Nice try, Ian … but yes, it’s custom: I will post a photo later

MichaelG.

Tricky lighting under the radiator … but hopefully this will suffice:

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MichaelG.

There is usually a laminated on plastic polariser layer on the display panel front face, and the problem is probably due to degradation of this. The polariser is essential to LCD operation. I have no idea if there is any easy cure.

Thanks for that, Malcolm … I fear you may be correct

MichaelG.

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Ref, __ https://www.j-display.com/english/technology/lcdbasic.html

Edited By Michael Gilligan on 20/01/2023 06:31:07

I am sure Malcolm is correct about this problem.

I have a very old LCD Honywell central heating programmer in the airing cupboard, obviously it is warm in there but the LCD display is slowly degrading exactly like MichaelG's scales....

Regards Derek

Hi MichaelG, although not as severe as your scales, I've had this credit card size calculator powered by just the little solar panel, which was a freebee just for enquiring about a quote. Bearing in mind that it's probably 25 years old, I'm not surprised it's suffering a similar effect, but I can't remember how long ago I first noticed it. It's been kicking about in all sorts of places like draws and just laying around wherever it was last used each time and got quite grubby at one time, and I'm amazed that it is still working. Is is totally sealed and there is no way of opening it up without prising it apart, which would probably render it useless, and I guess it will get worse over time, but I'm not really bothered about that. So whether it is just age or has had some kind of pressure damage that has caused it, I know not.

Regards Nick.

Edited By Nicholas Farr on 20/01/2023 08:35:14

Looks like a basic twisted nematic display where the seal has failed. I suspect there may be no way back. Shadows can occur with these displays when the LCD cell shrinks at low temperatures and these may recover unless the seal has been damaged and the fluid leaks out.

Thanks everyone

I will just continue using it as-is, and hope it doesn’t get much worse.

Eventually … I might be able to couple the excellent gauge to a remote display

But there is a lot on the to-do list before that’s likely to happen !

MichaelG.

I concur with you PaulG, Display will only get worse over time.

Standard failure mode on twisted nematic displays. Its what they all do, eventually. I'm told that the guys and gals at Malvern involved in developing the things in the first place pretty much threw a major party when they managed to get them to run for a month before the edges started going.

Basically running for a month proved that the things could be engineered into something practical rather tan being a lab curiosity coerced into working for long enough to get more funding by detremination, low cunning and serious cursing.

Clive

Even if the display is not terminal be careful with heat.

Years ago I wore an early LCD watch in the sauna and all of the figures disappeared, only returning weeks later.

Paul G is correct.

It can ony get worse. any attempt to heat or cool can only (not will) make it worse not better. leave it be and try to avoid temperature extremes.

Robert.

Edited By Robert Atkinson 2 on 20/01/2023 12:40:59

Duly noted

I will now engage Infinite Improbability Drive and wait for the ‘New Old Stock’ spares to appear on ebay

MichaelG.