Although Twisted Nematic LCDs may be driven in a time 

multiplexed fashion to increase the display information, 

they are restricted in terms of reduced contrast and limited 

viewing angle. To achieve more highly multiplexed displays, 

super twist technology is applied.

Super Twisted Nematic LCDs have a twist that is greater

than 90° but less than 360°. Currently most STN displays

 are made with a twist between 180° and 270°. The higher

 twist angles cause steeper threshold curves which put the 

on and off voltages closer together. The steeper thresholds 

allow multiplex rates greater than 32 to be achieved.

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