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:
Apr. 16, 2002
Filed:
Jul. 10, 1991
Applicant:
Inventors:
Neil Alexander Cade, Rickmansworth, GB;
David Francis Howell, Maidenhead, GB;
Assignee:
GEC-Marconi Limited, , GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J 1/16 ; H01J 2/946 ;
U.S. Cl.
CPC ...
H01J 1/16 ; H01J 2/946 ;
Abstract
A high-speed field emission vacuum switching device comprises a cathode tip formed on a substrate, an extraction grid close to the cathode tip, and a modulator grid spaced from the cathode tip by a dielectric layer. The grids have apertures aligned with the cathode tip. An anode is spaced from the modulator grid by a dielectric layer. By use of the modulator grid, a substantial improvement in high-frequency switching performance can be achieved. A collector grid may be provided between the extraction grid and the modulator grid, and a cut-off grid may be disposed between the modulator and collector grids.