FFS technology is based on the use of electrical field lines parallel to the substrate surface, just as in IPS technology. Like in IPS, this allows excellent viewing angle dependence. The difference between FFS and IPS is in the electrode configuration: in FFS, the strip electrodes have the same electrical potential, so that they can be placed close together. This in turn allows higher transmission, since the area above the electrodes can also contribute to the switching process.
Excellent viewing angle dependence, high transmission and touch function enablement at low voltages
The figure shows the electrode configuration, with the lower level representing the counter electrode. The electrical field lines are shown. This field configuration is created by the combination of a flat electrode with strip electrodes. The largest electrical field strength is at the fringe of the strip electrodes, giving FFS technology its name. The high field strengths close to the fringes of the strip electrodes allow very effective switching even at low voltages. The configuration of the electrical fields leads to higher transmission than in an IPS display, while still retaining the excellent viewing angle dependence of IPS. Another advantage is the low sensitivity to pressure on the display, making FFS technology ideal for touch displays, such as in smartphones and tablet PCs.
Our LCD Explorer visually demonstrates how an FFS display works.