The polarization is blocking non-perpendicular light.  That's part of the
process, to only use light which is aligning with the top layer.  Other light is
unwanted or not needed anyway for the action of the LCD.  You would also need to
think in terms of waves, not the simple description there at the web page.  The
upper polarizing filter is allowing all up and down (or back and forth)
lightwaves to enter while the lower one is allowing side to side waves.  When
the voltage is applied you don't see past the second polarizing filter hence
it's darkened.  I think that's right anyhow.  So any other light is negligible,
only the one direction of waves is used in the case of that TN type LCD display
example there.  It's then refracted (not sure that's the word for it) around 90
degrees to pass through the bottom layer when nothing is displayed.

Bob

"Tor Olav Kristensen" <tor### [at] hotmailcom> wrote in message
news:38C6FE39.D0FAC7F1@hotmail.com...
| I got courius about LCD's and did a search for info.
|
| I found a brief explanation of LCD's here:
|
| http://www.sharp.ca/lcd_principles.html
|
| But I don't understand what happens when non-
| perpendicular (to the glass) light rays enters the LCD.
|
| Can anybody explain?
|
| Tor Olav Kristensen wrote:
|
| > ...
| > To model a LCD more correctly, I guess you may take into account
| > the effect that two polarizing layers (90 deg on each other) some
| > distance apart, has on the light.
| > ...
| > You may also model the different layers of glass and liquid crystal that
| > are inside these.
|
| mailto:tor### [at] hotmailcom
| http://www.crosswinds.net/~tok/tokrays.html
|
|

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