TN displays have a 90° or less twist (the rotation of the molecules
from one plane of the display to the other). All passive direct drive,
active matrix, and most passive low level (x2 to x32) multiplexed LCDs have a 90° twist.
The basic Twisted Nematic (TN) LCD consists of a layer of liquid
crystal material supported by two glass plates. The liquid
crystal material is a mixture of long, cylindrically shaped
molecules with different electrical and optical properties, depending on direction.
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