Large-area individually addressable multi-beam x-ray system and method of forming same

Patent 6876724 Issued on April 5, 2005. Estimated Expiration Date:

January 22, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventors

Assignee

The University of North Carolina at Chapel Hill

Application

No. 10051183 filed on 01/22/2002

US Classes:

378/122, Field emisssion or cold cathode378/119SOURCE

Examiners

Primary: Bruce, David V.
Assistant: Song, Hoon

Attorney, Agent or Firm

Burns, Doane, Swecker & Mathis, L.L.P.

International Class

H01J036/06

Abstract

A structure to generate x-rays has a plurality of stationary and individually electrically addressable field emissive electron sources with a substrate composed of a field emissive material, such as carbon nanotubes. Electrically switching the field emissive electron sources at a predetermined frequency field emits electrons in a programmable sequence toward an incidence point on a target. The generated x-rays correspond in frequency and in position to that of the field emissive electron source. The large-area target and array or matrix of emitters can image objects from different positions and/or angles without moving the object or the structure and can produce a three dimensional image. The x-ray system is suitable for a variety of applications including industrial inspection/quality control, analytical instrumentation, security systems such as airport security inspection systems, and medical imaging, such as computed tomography.

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