A form of display used in television, in which light output is produced from the interaction between an electric current and an ionized inert gas such as neon. The display consists of a matrix of individual cells, one per pixel. A typical monochrome or grey-scale display generates red or orange light. Colour systems generate ultraviolet radiation, which excites phosphors (red, green, and blue) on the surface of the display; the excited phosphors emit light on return to the ground state. Plasma panels are rugged, largely immune to external fields, and do not suffer from flicker. Fabrication of large displays is possible. The device is essentially bistable so no special circuitry is required to isolate individual cells from their neighbours.