Varian Medical Systems, Inc.

Varian Medical Systems Technologies, Inc.

Varex Imaging Corporation

Steve Bandy

Gary Fredric Virshup

James T Arnold

David H Humber

Michael C Green

James Russell Boye

Robert C Treseder

Dennis H Runnoe

Clifford K Nishimoto

Jared Starman

An apparatus and method comprising a cathode structure which can be a cylindrical filament coiled in a helix or which can be constructed of a ribbon or other suitable shape. The cathode structure can be heated by passage of an electrical current, or by other means such as bombardment with energetic electrons. Selected portions of the surface of the cathode structure have an altered property with respect to the non-selected portions of the surface. In one embodiment, the altered property is a curvature. In another embodiment, the altered property is a work function. By altering the property of the selected portions of the surface, the electron beam intensity is increased, and the width is decreased.

Cathode structures for X-ray tubes

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.

Filament assembly having reduced electron beam time constant

A method is described. A total number of traps to be filled in a detector of an imaging system is estimated based on a measured signal sensed by the detector. The measured signal is adjusted based on the estimated total number of traps and a current trap state of the detector. The trap state of the detector is subsequently updated.

Gain/lag artifact correction algorithm and software

An integrated bearing assembly is provided, comprising a bearing housing defining an axial cavity in which a shaft is disposed. The shaft is rotatably supported by at least two bearing sets. The axial cavity defines three regions, each having distinct diameters. A pair of first regions defines cavity diameters sufficient to receive the bearing sets. A pair of second regions defines cavity diameters such that a small gap is defined between the inner surface of the cavity and the shaft. The third region cooperates with the shaft to define a cylindrical volume containing a coolant. Wettable coatings are utilized in the cylindrical volume to allow free flow of, and maximum contact with, the coolant. Non-wettable coatings are provided in the second regions to contain the coolant. The second regions also function as bearing spacers, thus simplifying bearing assembly design, assembly, and performance.

Integrated bearing assembly

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Sunnyvale, CA, United States of America

Steve Bandy