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:
Dec. 27, 1977
Filed:
Dec. 31, 1975
Viktor W Pleil, Wheaton, IL (US);
Picker Corporation, Cleveland, OH (US);
Abstract
A dual filament, rotary anode X-ray tube generates X-radiation of extraordinary uniform cross-sectional intensity by focusing a pair of electron flows on a target to produce partially overlapping focal spots. A pair of electron-emitting filaments are independently and adjustably excited for producing the flows of the electrons, each of which produces a line focus-type focal spot. The filaments are positioned in respective focusing cups which are configured and electrically biased to provide a degree of focal-spot overlap which produces a uniform distribution of electrons on the combined focal spots. The uniform electron distribution on the combined focal spots produces a uniform distribution of emitted X-radiation. In another embodiment the electrons from the respective filaments are focused to provide radially aligned and adjacent inner and outer focal spots on the target. The flow of electrons to the outer focal spot is more heavily concentrated than the flow to the inward focal spot. This compensates for the reduced amount of time which the outer focal spot area is receiving electrons compared with the inner focal spot area. This compensation increases the maximum intensity of an X-ray beam that can be emitted by the rotary target.