Double SuperTwisted Nematic (DSTN)
From The Glossary of Digital Photography
Also called Dual SuperTwisted Nematic. An LCD display that has more contrast than other types of LCD displays. DSTNs have a lower-quality image display and a slower response time, but they are less expensive to manufacture. The dual refers to a dual scanning process in which the screen is divided in half and each half is scanned at the same time. This gives the display a sharper appearance.
