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Will an LCD be damaged in a vacuum oof less than 10 Torr?
- Thread starter ScottI2R
- Start date
I would guess off hand... NO!
It is a liquid after all. Barely sandwiched inside very very thin glass. It would probably bulge and quit working before actually exploding. Not sure. You want to send me one, I'll test the theory for you. Anything that has a running display would work. That way I can see if it quits working thru my clear vacuum chamber. I actually have nothing I can do that to presently.
I can no-way get clear down to <10 Torr but, if there is going to be problems, it will be well before that.
Keith Cress
Flamin Systems, Inc.-
It is a liquid after all. Barely sandwiched inside very very thin glass. It would probably bulge and quit working before actually exploding. Not sure. You want to send me one, I'll test the theory for you. Anything that has a running display would work. That way I can see if it quits working thru my clear vacuum chamber. I actually have nothing I can do that to presently.
I can no-way get clear down to <10 Torr but, if there is going to be problems, it will be well before that.
Keith Cress
Flamin Systems, Inc.-
MacGyverS2000
Electrical
Dime store LCD throw-away watch would be a cheap and easy to source test subject...
Dan - Owner
Dan - Owner
- Thread starter
- #4
Thanks Kieth. I actually am not sure if my pump will go that low either. I guess I'll find out. I need that to boil out water.
Dan,
That is exactly how I plan to test it. I just figured if somebody already had....well, saves me an LCD...
Thanks again,
Scott
In a hundred years, it isn't going to matter anyway.
Dan,
That is exactly how I plan to test it. I just figured if somebody already had....well, saves me an LCD...
Thanks again,
Scott
In a hundred years, it isn't going to matter anyway.
The way they get the twisted-nematic fluid inside a LCD is by using a vacuum. Assembled sandwich-glass LCDs (without the polarizers) are put in a small vacuum chamber along with a container of the fluid. A vacuum is pulled and the LCDs are dipped into the fluid. Air is let into the chamber and the fluid is pulled into the LCD. Epoxy is applied to the fill port to seal the LCD.
I see no problem with a smaller passive LCD in a vacuum. Slight swelling of the fluid may cause bi-refringement issues (rainbow-color as the glass spacing varies) but the LCD should still work.
However, I don't know enough about the larger active matrix color LCDS used in cell phones and computers to say anything about them. It could be that the glass-glass spacing is far more critical
I see no problem with a smaller passive LCD in a vacuum. Slight swelling of the fluid may cause bi-refringement issues (rainbow-color as the glass spacing varies) but the LCD should still work.
However, I don't know enough about the larger active matrix color LCDS used in cell phones and computers to say anything about them. It could be that the glass-glass spacing is far more critical
- Thread starter
- #7
- Thread starter
- #9
Hey smoked,
Worked on my cell. Really dont know what pressure I got down to, but I know on the CO2 lasers I used to work on, water was gone by 8 torr. Started to really boil out around 10-11 and then was gone by 8. Really played heck on the vacuum pumps. Lots of oil changes.
Worked on my cell that landed in the dog water dish when I bumped it off the counter opening the toaster oven....I know, I know, not for your home, for your work! It WAS my work cell phone though, and a neat experiment!
Thanks,
Scott
In a hundred years, it isn't going to matter anyway.
Worked on my cell. Really dont know what pressure I got down to, but I know on the CO2 lasers I used to work on, water was gone by 8 torr. Started to really boil out around 10-11 and then was gone by 8. Really played heck on the vacuum pumps. Lots of oil changes.
Worked on my cell that landed in the dog water dish when I bumped it off the counter opening the toaster oven....I know, I know, not for your home, for your work! It WAS my work cell phone though, and a neat experiment!
Thanks,
Scott
In a hundred years, it isn't going to matter anyway.
I have a small blower that was fouled with some dry powder with stinking perfume in it like baby powder. I have tried everything to get the odor out. I recently ran 30 vacuum/oven cycles on it. All it did was sort of twist the odor. The blower housing is lined with coated open cell foam which greatly increased the problem. I finally gave up on the vacuum/heat method and started cutting out the foam only to discover the adhesive that is virtually impossible to remove is the real culprit! <shaking head>
I also discovered what happens when you run a vacuum pump with a seal leak on the chamber door at about 5mm Hg for an hour. It filled then entire building with an oil haze. Dang!
Keith Cress
Flamin Systems, Inc.-
I also discovered what happens when you run a vacuum pump with a seal leak on the chamber door at about 5mm Hg for an hour. It filled then entire building with an oil haze. Dang!
Keith Cress
Flamin Systems, Inc.-
Good information to know. Thanks for posting the results.
itsmoked - to remove adhesive, try CRC brake cleaner. It's in a red can found at most auto parts places. I even use it to remove label residue from the front of test equipment, books, and manuals. Drys in a few minutes, leaves no residue or smell. Just don't get it on syrene plastics.
itsmoked - to remove adhesive, try CRC brake cleaner. It's in a red can found at most auto parts places. I even use it to remove label residue from the front of test equipment, books, and manuals. Drys in a few minutes, leaves no residue or smell. Just don't get it on syrene plastics.
Howdy Comcokid!
This whole blower is grey plastic... I tried my favorite, methanol, which caused the adhesive,(with a million flegs of foam), to smear around into bigger clumps but it was still very hard to remove. The plastic started to haze and I think come off on the paper towels. Hard to tell as the foam and the plastic and the adhesive are all grey.
I do have a can of CRC brake cleaner about 6 feet from the blower! I will drip a drop somewhere on the housing and see what happens before I commit.
Many thanks for the suggestion. I keep thinking there must be some magic chemical bullet that will do the trick..
I tried soaking it in orange cleaner and Micro, (a strong lab cleaner) with no effect what-so-ever.
Hope the CRC works.
Next stop hot lye??![[nosmiley]](/data/assets/smilies/nosmiley.gif "[nosmiley] [nosmiley]")
Thanks.
Keith Cress
Flamin Systems, Inc.-
This whole blower is grey plastic... I tried my favorite, methanol, which caused the adhesive,(with a million flegs of foam), to smear around into bigger clumps but it was still very hard to remove. The plastic started to haze and I think come off on the paper towels. Hard to tell as the foam and the plastic and the adhesive are all grey.
I do have a can of CRC brake cleaner about 6 feet from the blower! I will drip a drop somewhere on the housing and see what happens before I commit.
Many thanks for the suggestion. I keep thinking there must be some magic chemical bullet that will do the trick..
I tried soaking it in orange cleaner and Micro, (a strong lab cleaner) with no effect what-so-ever.
Hope the CRC works.
Next stop hot lye??
Thanks.
Keith Cress
Flamin Systems, Inc.-
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