Patent 7157841 was granted and assigned to Futaba on January, 2007 by the United States Patent and Trademark Office.
An electron tube includes a vessel, a primary linear member installed in the vessel, an electrode disposed in the vessel, a first auxiliary linear member and a second auxiliary linear member disposed at different heights to interpose the primary linear member therebetween, and a plurality of fixing members. The fixing members are formed at a single substrate for constituting a part of the vessel, for fixing end portions of the first auxiliary and the second auxiliary linear member thereto.