Abstract: The electron impact surface of an anode/collector is coated with a carbon nanotube coating to reduce the production of secondary electrons and, concomitantly, to suppress the formation of neutral gases and plasma. A carbonizable resin is first applied to the electron impact surface, followed by a coating comprised of carbon nanotubes. The coating is pyro-bonded to the surface by heating the anode/collector to over 700° C. in a non-oxidizing atmosphere. Next, the anode/collector is heated to over 1000° C. while a low-pressure hydrocarbon gas, for example, methane, is flowed over the carbon nanotube coating. The gas decomposes and creates a smooth, non-porous, rigid surface on the carbon nanotube coating. The anode/collector is then heated in a vacuum to evaporate any residual water in the carbon nanotube coating.

Abstract: A method for making a field emission cold cathode for use in vacuum tubes. A carbon velvet material is coated with a low work function cesiated salt and bonded to a cathode surface. Alternatively, the carbon velvet material is bonded to the cathode surface before being coated with the cesiated salt. The coating may be applied by spraying the carbon velvet material with a cesiated salt solution, or by dipping the material into a crucible of molten cesiated salt. This abstract is provided to comply with the rules requiring an abstract, and is intended to allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning the claims.

Abstract: A vacuum tube having its anode/collector coated with carbonized resin plus pyrocarbon material to reduce out-gassing and secondary electron emission and the method of coating the anode/collector.

Abstract: A field emission cold cathode for use in vacuum tubes. A carbon velvet material is coated with a low work function cesiated salt and bonded to a cathode surface. The cathode will emit electrons when an electric field is applied. The carbon velvet material is comprised of high aspect ratio carbon fibers embedded perpendicular to a base material.

Abstract: A vacuum tube having its anode/collector coated with carbon nanotube-based material in which five percent or more of the carbon nanotubes are aligned parallel to the anode/collector's surface.