Importance

Loading Importance Indicators...

Abstract

An electron field emission device includes a field emissive cathode which may include a plurality of sharp field emitter tips 2. First and second grids 4 and 7 are located between the cathode and an anode. The grids comprise parallel strips of electrically conductive material, those of the first grid being arranged orthogonal to those of the second. Applications of suitable voltages to the grids enable selected regions of the cathode to be made electron emissive and produce collimated electron beams. The anode may be phosphor coated to produce a visible display or an infra-red image may be produced. Relatively low voltages may be used to switch the regions on and off. As the beams are collimated, the anode may be located a relatively large distance from the cathode, enabling high voltage phosphors to be used.

Loading the Abstract Image...

First Claim