Patent ID: 6635978
Filing Date: 2003-10-21
Classification: H01J

Abstract:
An electron tube with an axial beam, comprising, in a vacuum envelope, an electron gun for creating and modulating an electron beam directed in a forward direction, said electron gun having a front part and a rear part, said front part comprising an emissive cathode and an apertured portion of a grid, and said rear part comprising a heater for heating the cathode, said rear part being located behind the cathode when looking in said forward direction, said grid being made from a pyrolitic graphite single material and having an axial tubular skirt extending in a rearward direction opposite said forward direction until behind the front part of the electron gun, and said tubular skirt being fixedly mounted on an electrically conductive metallic grid support, said metallic grid support located backwards from said front part when looking in said forward direction.