X-ray tube electron sources
First Claim
1. An electron source for an X-ray scanner comprising:
- a. at least one electron emitter in a first plane, wherein said electron emitter is positioned between a first suppressor and a second suppressor and wherein each of said first and second suppressors are held at a constant voltage;
b. plurality of extraction elements in a second plane, wherein the first plane and second plane are substantially parallel and separated by a contiguous space, and wherein a space between two adjacent extraction elements and said at least one electron emitter define a source region; and
c. a controller that applies an electrical potential to certain of said plurality of extraction elements wherein said application of the electrical potential causes electrons to be moved from a first source region to a second source region.
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Accused Products
Abstract
An X-ray tube includes an emitter wire enclosed in a suppressor. An extraction grid comprises a number of parallel wires extending perpendicular to the emitter wire, and a focusing grid comprises a number of wires parallel to the grid wires and spaced apart at equal spacing to the grid wires. The grid wire are connected by means of switches to a positive extracting potential or a negative inhibiting potential, and the switches are controlled so that at any one time a pair of adjacent grid wires are connected together to form an extracting pair, which produce an electron beam. The position of the beam is moved by switching different pairs of grid wires to the extracting potential.
112 Citations
33 Claims
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1. An electron source for an X-ray scanner comprising:
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a. at least one electron emitter in a first plane, wherein said electron emitter is positioned between a first suppressor and a second suppressor and wherein each of said first and second suppressors are held at a constant voltage; b. plurality of extraction elements in a second plane, wherein the first plane and second plane are substantially parallel and separated by a contiguous space, and wherein a space between two adjacent extraction elements and said at least one electron emitter define a source region; and c. a controller that applies an electrical potential to certain of said plurality of extraction elements wherein said application of the electrical potential causes electrons to be moved from a first source region to a second source region. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33)
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Specification