摘要 |
<p>A cathode structure of triode type comprises, superposed, a cathode forming electrode (13) and supporting a layer of electron emitting material (14), an electrical insulating layer (11) and a grid electrode (15). An opening (12) cut in the grid electrode and in the electrical insulating layer exposes the layer of electron emitting material. The layer of electron emitting material is situated in the central part of the opening in the grid electrode. An Independent claim is also included for a flat field emission screen incorporating several of the above cathode structures.</p> |