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:
Sep. 11, 1979
Filed:
May. 02, 1977
Applicant:
Inventor:
Robert A Gange, Belle Mead, NJ (US);
Assignee:
RCA Corporation, New York, NY (US);
Primary Examiner:
Int. Cl.
CPC ...
H01J / ; H01J / ;
U.S. Cl.
CPC ...
315366 ; 315105 ; 313422 ;
Abstract
A series of discrete heating current pulses are passed through a line cathode so as to cause the cathode to emit electrons therefrom. Between each consecutive pair of pulses is a cooling period during which no heating current flows through the cathode. Current is extracted from the cathode during this cooling period. In a preferred embodiment for an image display device, the heating pulse duration is about 10 .mu.sec and the cooling period is about 50.mu.sec. In this scheme, the heating period corresponds roughly to the horizontal retrace time between line times of 50.mu.sec.