CNT based field emission display

Carbon nanotubes (CNT) are extensively used in many applications. One among them is field emission flatbed display. Field emission is the emission of electrons from a solid when subjected to a strong electric field. A high electric field can be generated at the tip of a sharp object. Electrons produced due to this high electric field are allowed to strike a green phosphor screen which produces coloured images. Silicon and tungsten are the commonly used tip materials. But CNT tips offer superlative performances. CNT allows very small radius of curvature for at the tip. Covalent bonding is strong in CNT which makes it chemically and physically inert. This eliminates the risk of chemical poisoning and sputtering. Since CNTs are mechanically strong and chemically stable, they are capable of carrying strong current. Risk of field induced sharpening is also very less when CNTs are used. CNT system requires moderate vacuum conditions and less energy for its operation. In field emission displays carbon nanotubes are arranged in an array.