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:
Aug. 06, 2002
Filed:
Dec. 31, 1999
Applicant:
Inventors:
Keith D. Jamison, Austin, TX (US);
Donald E. Patterson, Pearland, TX (US);
Assignee:
Extreme Devices, Inc., Austin, TX (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01J 7/24 ;
U.S. Cl.
CPC ...
H01J 7/24 ;
Abstract
A field emission cathode providing for dynamic adjustment of beam shape is disclosed. Beam shape adjustment is accomplished by segmenting the gate electrode of a gated field emission cathode and independently driving the various gate segments to form the desired beam shape. Segments can be turned on and off as the beam is deflected allowing dynamic correction of aberrations in the beam. A focus lens can be placed on the gated cathode to produce a parallel electron beam. In addition, a hollow cathode can be produced to minimize space charge repulsion in a beam.