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. 23, 1980
Filed:
Dec. 22, 1978
Applicant:
Inventors:
Paulus J Hovens, Eindhoven, NL;
Miloslav Tryzna, Eindhoven, NL;
Wouter Smeulers, Eindhoven, NL;
Willem H Amsen, Eindhoven, NL;
Assignee:
U.S. Philips Corporation, New York, NY (US);
Primary Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
358242 ; 358243 ; 358 74 ;
Abstract
In a television picture display device wherein a cathode of a picture display tube is driven by an emitter-follower and a control signal for a beam current reference level control circuit is obtained from the collector circuit of this emitter-follower, measures are taken to compensate for leakage currents from and to the cathode. To this end a blacker-than-black current compensation circuit is provided while furthermore it is ensured that the blacker-than-black curent can be processed by the beam current reference level control circuit.