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Tunnel Vision On Monochrome Active Matrix Powerbooks

Shaddam IV

Well-known member
I've now let it run for 2 x 6 hours. I let the screen cool down and tried it. No change (tunnel vision is still creeping in after a few minutes). Maaaaaybe a bit slower than before. But it has the same extent. So I'll keep toasting the machine.
 

Shaddam IV

Well-known member
The result of this experiment is: The IR lamp does not sufficiently ameliorate the tunnel vision. I'm stopping now. Interestingly, the screen didn't get any worse either, although it's been exposed to a lot of heat. If the tunnel vision effect is really caused by moisture, that moisture apparently doesn't (possibly because it can't) escape from the inner areas of the display when heated.
 

Shaddam IV

Well-known member
I put a 180's screen with moderate tunnel vision in the oven at 98°C for 12 hours. The tunnel vision effect is much slower to appear now, but appear it does (after 30 minutes or so). My conclusion is that the liquid crystals themselves are degraded, and that short of cracking open the panel, scraping out the liquid crystals (they appear to look like goo), and putting in a new layer, there is no permanent fix. I have no clue as to how to open an LCD to get the crystals out short of breaking it apart - so I'm giving up for now.
 

Paralel

Well-known member
I put a 180's screen with moderate tunnel vision in the oven at 98°C for 12 hours. The tunnel vision effect is much slower to appear now, but appear it does (after 30 minutes or so). My conclusion is that the liquid crystals themselves are degraded, and that short of cracking open the panel, scraping out the liquid crystals (they appear to look like goo), and putting in a new layer, there is no permanent fix. I have no clue as to how to open an LCD to get the crystals out short of breaking it apart - so I'm giving up for now.

Replacing the LC in the screen is impossible. The glass sandwich part of the screen can never be taken apart successfully.
 
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