The Field Emission Display(thin CRTs) are a relatively new display type. It has a image contrast equal to a normal CRT but has a thickness of under 1cm. Unlike the normal CRT the FED have electron emitters for every phosphor dot. This means that there is no need for a deflection system thus that the long 'neck' and the curves of the normal CRT isn't needed. Also, the electron cannons can be replaced by an array of small electron emitters.

The basic buildup of a FE cell:

    emitter  Phosphor
     layer   dot
      |       |

B   | :   |_|  | |
a   |-:       *| | F
s   |-:   F   *| | a
e   |-:   o g *| | c
    |-:   c r *| | e
l   |-:   u i *| | p
a   |-:   s d *| | l
y   |-:   i   *| | a
e   |-:   g   *| | t
r   |-:    _  *| | e
    | :   | |  | |

A FE display consists of one cell like this for each phosphor dot (3 dots per pixel). The base layers of the cells on the same row, is connected together. The top emitter layer are connected in columns. This makes a column/row system so each dot can be individually addressed. To light the phosphor in one cell you address connect voltages to the appropriate row and to the column. This makes the emission spikes send out electrons. Since each cell has many spikes(often more than 3000), the 'wear' on one individual spike is minimal. The focusing grid's electric field collimates the flow of electrons so that they only hit the correct dot.

This form of display have a higher brightness and contrast than the Active Matrix LCD(TFT display), but needs an accelerating voltage. But unlike the CRT, that may have 15kV to 25kV, it needs only 500V-1kV.

Due to its compact size and lower voltages than CRTs, and lower weight than plasma displays it has the potential to become an important technology in future computer screens. But due to the need for vaccum inside the display, it has proven to be hard to make a FED larger than 10" that doesn't have a high danger of self implosion.

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