"When no voltage is applied to a TN liquid crystal cell, polarized light passes through the 90-degrees twisted LC layer. In proportion to the voltage applied, the liquid crystals untwist changing the polarization and blocking the light's path. By properly adjusting the level of the voltage almost any gray level or transmission can be achieved."
anon
Modern screen technologies such as OLED (organic light-emitting diodes) that are commonly used in smart phones and high end TVs have an advantage over LCD displays as instead of relying on illumination from backlight, each "pixel" can be illuminated individually.
acb575
Wanted to know more about how LCD displays work and this article was simplified and clear to understand. They also show images of the polarized sunglasses example that Prof. Kavyon mentioned in class (the screen going black when the sunglasses are turned)- https://www.explainthatstuff.com/lcdtv.html
How is it that the light coming into the box is twisted? Is it controlled by the polarizer as it enters the box?
No, the light is twisted by TN-effect (https://en.wikipedia.org/wiki/Twisted_nematic_field_effect).
"When no voltage is applied to a TN liquid crystal cell, polarized light passes through the 90-degrees twisted LC layer. In proportion to the voltage applied, the liquid crystals untwist changing the polarization and blocking the light's path. By properly adjusting the level of the voltage almost any gray level or transmission can be achieved."
Modern screen technologies such as OLED (organic light-emitting diodes) that are commonly used in smart phones and high end TVs have an advantage over LCD displays as instead of relying on illumination from backlight, each "pixel" can be illuminated individually.
Wanted to know more about how LCD displays work and this article was simplified and clear to understand. They also show images of the polarized sunglasses example that Prof. Kavyon mentioned in class (the screen going black when the sunglasses are turned)- https://www.explainthatstuff.com/lcdtv.html