Electron tube with pyrolytic graphite heating element
AssigneeU.S. Philips Corporation
InventorsBernhard Lersmacher, Hans Lydtin, Horst Seifert, Johannes W. A. Krol
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Abstract
In a thermionic cathode having a planar emissive body and a heating element of pyrolytic graphite which is provided on the side of the emissive body remote from the emissive surface of the emissive body, a uniform temperature distribution adjusts during operation throughout the overall emissive surface when the heating element is planar and the crystallographic c-axis of the pyrolytic graphite extends everywhere normal to the surface of the heating element facing the emissive body. As a result of this the possibility is obtained of realizing a planar, "rapid", induction-free unipotential cathode having a substantially ideal homogeneous temperature distribution.
Claims5
An electron tube comprising a thermionic cathode including a planar emissive body having an emissive surface and a heating element of pyrolytic graphite which is provided on the side of the emissive body remote from said emissive surface wherein the heating element is planar and the crystallographic c-axis of the pyrolytic graphite extends everywhere normal to the surface of the heating element facing the emissive body.
Dependencies are inferred from the claim text.