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FED means field emission display

A field emission display is a type of flat panel display using field emitting cathodes to bombard phosphor coatings as the light emissive medium.

Field emission displays are very similar to cathode ray tubes, however they are only a few millimeters thick. Instead of a single electron gun, a field emission display (FED) uses a large array of fine metal tips or carbon nanotubes (which are the most efficient electron emitters known), with many positioned behind each phosphor dot, to emit electrons through a process known as field emission. Because of emitter redundancy, FEDs do not display dead pixels like LCDs even if 20% of the emitters fail. Sony is researching FED because it is the flat-panel technology that comes closest to matching the picture of a CRT.

Like LCDs, FEDs are energy efficient and could provide a flat panel technology that features less power consumption than existing LCD and plasma display technologies. They can also be cheaper to make, as they have fewer total components. As of yet, however, there are no consumer production models available in the United States, although small demo panels have been produced.

A field emission display (FED) is a low power, flat cathode ray tube type display that uses a matrix-addressed cold cathode to produce light from a screen coated with phosphor materials. The principle of the field emission display is similar to that of the traditional cathode ray tube display. Field emission displays, like cathode ray tubes, display a color image by emitting light of a predetermined color through the bombardment of electrons onto a field emitter array (FEA) coated with phosphor. They both emit electrons to hit the fluorescent medium on a substrate in vacuum. Electron emission includes field electron emission, secondary electron emission, and photoelectric emission, as well as thermionic emission. A cold cathode is the cathode that performs electron emission by field electron emission, which occurs due to a tunnel effect when a strong electric field is applied to the vicinity of the surface of a substance to lower the potential barrier on the surface. The cathode ray tube display emits electron beams by a single electron gun and controls the direction of the electron beams by using a polarization plate. Instead, the field emission display is composed of hundreds of thousands of active cold emitters, each of which corresponds to a pixel independently, so no polarization plate is needed. Field emission displays (FEDs) apply a strong electric field from a gate to a field emitter disposed on a cathode layer at regular intervals, thereby emitting electrons from the field emitter, colliding the electrons with a phosphor material of an anode layer, and emitting .light The cold cathode electron source is broadly divided into a field emission electron source and a hot electron type electron source. The former includes a spindt type electron source, a surface conduction type electron source and a carbon nanotube type electron source. The latter includes an MIM (metal-insulator-metal) type electron source stacked with metal-insulator-metal and an MIS (metal-insulator-semiconductor) type electron source stacked with metal-insulator-semiconductor. When displaying an image in the field emission display, a driving method called a line sequential scanning scheme is used standardly. Display in each of the frames is performed for each scan line (horizontally). All the cold cathode electron sources corresponding to the number of data lines on the same scan line are operated at the same time.

Field emission display (FED) technology has been proposed as a display technology that enjoys the advantages of allowing for wide viewing angles as well as being thin and light weight. The field emission display has the advantage of high image quality found with the conventional cathode ray tube display. Also, the field emission display has advantages of high yield, fast reacting time, good performance in displaying coordination, having high brightness, light and thin structure, wide range of color temperature, high mobile efficiency, excellent distinguishability of tilted direction, etc. in comparison with the conventional liquid crystal display that has the disadvantages of blurred view angle, limited range of usable temperature, and slow reacting time. Moreover, the field emission display emits light spontaneously. Field emission display has not only soft picture, rapid reaction, and clear brightness like CRT, but also possesses characteristics of lightness of flat display and low performance consumption. FED has advantages of light weight and thin profile, like liquid crystal display (LCD), and advantages of high brightness and self luminescence, like cathode ray tube (CRT). The image quality of the field-emission display is similar to that of the conventional cathode ray tube (CRT) display, while the dimension of the field-emission display is much thinner and lighter compared to the cathode ray tube display. Being self-illuminant, field emission display does not require a back light source like the liquid crystal display. In addition to the better brightness, the viewing angle is broader, power consumption is lower, response speed is faster, and the operation temperature range is larger. Through the construction of a high efficiency fluorescent film, the field emission display provides outstanding brightness performance even outdoors so it is thought as a quite competitive display panel and is even likely to replace the liquid crystal display. Field emission devices are used in a number of different applications, including displays, e-beam lithography, chemical analysis and space propulsion.

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