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:
Jun. 21, 1977
Filed:
Oct. 02, 1975
Applicant:
Inventors:
Reinhard Ziegler, Hamburg, DT;
Horst Seifert, Hamburg, DT;
Assignee:
U.S. Philips Corporation, New York, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ; H01J / ; H01K / ;
U.S. Cl.
CPC ...
3133 / ; 313304 ; 313338 ; 3133 / ;
Abstract
A dispenser cathode for a grid-controlled electron tube in which the emission of surface regions immediately opposite the control grid is reduced by providing projections above the emissive surface of fused, pore-closing portons which have a focussing effect. These projections may be formed by electron beam or laser beam welding.