The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 26, 2009
Filed:
Nov. 19, 2007
Steve Bandy, Sunnyvale, CA (US);
Gary F Virshup, Cupertino, CA (US);
Michael Curzon Green, Palo Alto, CA (US);
James Russell Boye, Salt Lake City, UT (US);
Dennis Runnoe, Salt Lake City, UT (US);
Robert Clark Treseder, Lynchburg, VA (US);
David Humber, Los Gatos, CA (US);
Steve Bandy, Sunnyvale, CA (US);
Gary F Virshup, Cupertino, CA (US);
Michael Curzon Green, Palo Alto, CA (US);
James Russell Boye, Salt Lake City, UT (US);
Dennis Runnoe, Salt Lake City, UT (US);
Robert Clark Treseder, Lynchburg, VA (US);
David Humber, Los Gatos, CA (US);
Varian Medical Systems, Inc., Palo Alto, CA (US);
Abstract
A filament assembly for use in an x-ray emitting device or other filament-containing device is disclosed. In one embodiment, an x-ray tube is disclosed, including a vacuum enclosure that houses both an anode having a target surface, and a cathode positioned with respect to the anode. The cathode includes a filament assembly for emitting a beam of electrons during tube operation. The filament assembly comprises a heat sink and a plurality of filament segments. The filament segments are configured for simultaneous emission of an electron beam for impingement on the target surface of the anode, and are electrically connected in series. Each filament segment includes first and second end portions that are thermally connected to the heat sink, and a central portion that can be configured with a modified work function for preferential electron emission.