Engineering phosphors for FEDs

The design and, more particularly, the voltage of operation of FEDs is determined, to a large extent, by availability of stable, efficient phosphors emitting with the required colour gamut. We have previously suggested there are three separate regimes for operating FEDs, e.g. those operating at: A) 300 eV or below, B) between 300-3000 eV, and C) above 3 keV. A recent review would indicate that the majority of manufacturers have chosen C), the high voltage route for initial FED developments. It is clear that, in the long term, low voltage of operation is desirable.