Epson PX-8 LCD Screen Fix

[Senior System Engineer]

Hello,
I recently acquired an Epson PX-8 Geneva that is in excellent condition (except for LCD screen).
I have torn it apart, replaced the batteries and tape drive belt and it is fully functional.
The problem is that the LCD screen is a disaster (see attached image).
I can read the text and the computer functions properly but I really want to fix the screen.
Per the manual, it is a twist nematic effect type lcd screen (TNM).
I have no problem tearing it apart if need be; However, I think the only aspect of lcd screens that can be repaired is polarizing laminations.
Does anyone know if that is the case with a TNM screen and if so, has anyone ever successfully re-laminated the polarizing layers?
Thanks,
Scott

 

[cjs]

I am guessing that you're asking specifically about TNM screens vs. other types of LCD displays, and you've already researched the various tutorials and the like on fixing "vinegar syndrome" by replacing the polarizer(s)? If not, this video by Shuichiro Hirakawa is a good introduction.

 

[Senior System Engineer]

Thanks cjs,
Yes, I have researched how to do it with polarizer laminations.
My biggest issue is that I'm not 100% sure this screen uses the polarizer laminations.
I also assume it uses the zebra stripe connectors which can be a pain to realign.
I'm just hoping someone can say "Yes, I've done it before on a P-8 and it is possible."
I'll wait a bit to see if I get any more responses and then decide if I want to take the plunge.
Thanks again,
Scott

 

[Senior System Engineer]

Well, I talked with Jeff Birt and he gave me some great direction.
I've stripped the front polarizer film off as well as the back reflective polarizer film.
It was the back one that was totally trashed.
Looks like the glue used to adhere the reflective film to the polarized film was defective (or heat/cold sensitive).
Anyway, I've ordered the reflective and transparent polarized adhesive films.
I hope that I am able to get the zebra strips placed properly upon rebuilding the screen.

Thanks,
Scott

 

[Senior System Engineer]

Hello Everyone,
I've completely stripped the polarizing film from the front and rear of the glass screen and have ordered new adhesive replacements.
I seem to have a major problem with the zebra strips...
There are normal zebra strips on the top and bottom edges of the screen; However, the left and right edges of the screen use a special 90 degree zebra strip.
The contacts are on the top of the glass so the strips come up and go over the top of the screen edge to make the connections.
They were slightly damaged during disassembly so I need to find some replacements.
I've attached pictures of the white end zebra strips.
The right angle is so thin, it split a little on both of the strips.
It's minimally possible that once under pressure that the connections will be ok but I would rather try replacing them.
Does anyone have any idea where I might get these right angle zebra strips?
Otherwise, does anyone have a spare LCD module or even another PX-8 that is for parts only?
Thanks,
Scott

 

[Paralel]

Oh, that is strange. I've never seen one like that. You can repair them with some effort. If you want some info on repair them, I can look up the info. If I remember it takes a few unusual tools.

 

[Senior System Engineer]

Paralel, I'll take any help I can get...Thank You