polarizing film to switch dark characters to light and background to to dark

Martin S. Shepherd · 04-16-2001, 03:38 PM

If your looking for a place to buy polarizing film for a reasonable price try "www.e-sci.com/genSci/7/1035/1081/W1081.html". I was able to buy only two pieces of film 50mm x 50mm for $4.95. If anyone knows of a better deal or of a place to buy self-adhesive film let me know.

Arby · 04-16-2001, 04:18 PM

50mm isn't near long enough to do an lcd...

Mine is about 40x150mm...

Martin S. Shepherd · 04-16-2001, 05:08 PM

Duh - and I just checked the next size up is 100mm x 200mm and is 30.95. Do you know where I can find a larger piece at a more reasonable price?

youngy · 04-16-2001, 08:10 PM

Does anyone know where I can get this stuff in Australia?

Tried Electronics stores, photographic wholesales, art places.

Help!

Arby · 04-18-2001, 11:31 AM

www.polarization.com has 12x19" sheets for $15, but they're not self-adhesive

Martin S. Shepherd · 04-19-2001, 07:19 PM

Thanks Arby, I ordered some. If anyone wants to pay me about $10.00 I'll send you what I don't use. It should be quite a bit since I only have a 4x20 character display and the minimum size sheet you can order is 12"x19".

Bj · 04-19-2001, 08:04 PM

Quote:

Originally posted by youngy:
<STRONG>Does anyone know where I can get this stuff in Australia?

Tried Electronics stores, photographic wholesales, art places.

Help!</STRONG>

I just went down to my local kodak place, and they said they could get me some. It comes in a A4 sheet, and isn't adhesive. But it will set you back $25 AUS. I never bothered with it after that.....

cpritchett · 04-20-2001, 07:48 AM

Since it isn't self-adhesive, what would be the best way to stick it on?

Oms · 04-20-2001, 11:39 AM

I didn't stick it on at all. The metal (or plastic) frame around the LCD is good enough to hold it snug against the glass. Just make sure you cut it to exactly the right size.

I'm less than impressed with the contrast, though. It looks very nice at night, but in daylight, it sucks, to be honest. I've convinced myself to go for a graphical VFD, one of these days...

Arby · 04-20-2001, 08:16 PM

If you redo the polarizing on both the front and the back of the lcd, you can get much better contrast. Of course, that's not easy.

Oms · 04-20-2001, 09:44 PM

Arby - I don't get it. Can you please explain in a little more detail. Why would redoing the polarizing on the back help? Redoing, how exactly? And why would it be more difficult than the front?

AFAIK, a normal LCD has its polarizers at right angles to each other. When you invert it, they become parallel. So I don't understand what you mean by "redoing the back".

Arby · 04-21-2001, 03:11 PM

http://mp3box.2y.net/temp/polarizingdiagram.jpg

The reason I said the back one is harder is that you have to be careful to not break off the conductive strips. They aren't on there that great.

Here's a picture of a LCD I did that way, and the contrast is fine in the daylight

http://csg.2y.net/mp3box/temp/jesse/06.jpg

Martin S. Shepherd · 04-21-2001, 05:27 PM

Arby, I noticed on your diagram that you stated that the rear piece of porazing film had to be vertically polarized, but not quite, because lcd twists the polarization slightly. Does it matter which way to rotate the film? And if it does matter, how do you figure out which way to rotate it without putting the display back together with a piece of film in the back?