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. 27, 1997
Filed:
Mar. 21, 1996
Stephen W Gravelle, Mequon, WI (US);
Steven D Hansen, Port Washington, WI (US);
Karl F Sherwin, Waukesha, WI (US);
General Electric Company, Milwaukee, WI (US);
Abstract
X-ray tube electron beam focusing utilizing a cathode having a large cavity therein in which an electron cloud is generated and which is shielded from the primary electric field between the cathode and the anode. The electron cloud flows from the cavity through a small narrow passage and into the primary electric field. An opposed spaced apart pair of electrical grids each comprising an array of individual electrode segments have selected opposed segments electronegatively biased to change the cross-section of the passing electron stream therebetween. The altered cross-section of the electron stream determines the size of the focal spot of the electron beam impacting the target anode.