Glossary definition of STN

Also known as: Super Twisted Nematic

STN (Super Twisted Nematic) is an improved type of passive matrix LCD display. Normal twisted nematic LCD displays consist of liquid crystal molecules, which have a helical structure (giving the twisted part of the name), and lie on a plate of glass. When in a normal state, polarized light can pass directly through these crystals, giving a clear appearance. However, when an electric field is applied, the crystal loses its twisted structure and light cannot pass, giving a darkened appearance.

STN grows on standard twisted nematic displays by rotating the director of the display by 270 degrees instead of the typical 90 degrees; this makes the display more responsive to voltage changes and widens the angle at which the display can be viewed.

The increased response of super twisted nematic displays means that greater contrast is possible at the same power level. STN displays go up to around 500 rows.