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:
Mar. 20, 1979
Filed:
Nov. 02, 1977
Applicant:
Inventor:
Richard A Tuck, Slough, GB;
Assignee:
E M I Varian Limited, Hayes, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
315-539 ; 313299 ; 313309 ; 313336 ;
Abstract
An electron emitter comprises field emitter zones formed by projections of field emissive material separated by regions which are not field emissive. An extractor electrode for applying an electric field to the projections and a focus electrode have openings aligned with the emitter zones and material particles aligned with the non-emissive regions. The electrodes form, when suitably energised electron focussing fields to focus electrons emitted from the zones.