Investigation of the Focus Characteristics of aTriode Structure in FED

In a field emission display panel, the triode structure¹ has been used to decrease the driving voltage. Because a very strong electric field has been appliedin front of the field emitters, the electron beam usuallydivergences in a normal triode structure^2;3. A new triode structure with an additional focus electrode has beenproposed⁴. A numerical program has been used to calculate the focus characteristic of this triode structure. Wealso analyze the variation of the current density distribution on the screen with different focus voltages.