The most recent advance has been the introduction of Film 

compensated Super Twisted Nematic (FSTN) displays. It adds 

a retardation film on the STN display that compensates for 

the color added by the birefringence effect. This enables a 

black and white display to be produced and provides for a

higher contrast and wider viewing angle.

The FSTN technology comes in a single coloration, Black characters 

on a White Gray background. Among the three technologies listed 

here, it is the most expensive one, but it has better viewing 

angle and contrast than the STN technology listed above.

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