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:
Jul. 08, 1986
Filed:
Mar. 21, 1984
Applicant:
Inventor:
Robert H Lacy, Bartlesville, OK (US);
Assignee:
Phillips Petroleum Company, Bartlesville, OK (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G09G / ;
U.S. Cl.
CPC ...
340721 ; 340709 ; 340734 ; 340724 ;
Abstract
A normal video signal and an overlay video signal are combined by supplying the normal video signal to the base of a first emitter follower transistor while the overlay video signal is supplied to the base of a second emitter follower transistor. The two transistors are biased such that the first transistor is at a slightly lower voltage than the second (overlay) transistor and is reversed biased (off) any time data is available from the overlay video signal.