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. 03, 1991
Filed:
Mar. 29, 1990
Applicant:
Inventors:
Stephen S Walker, Marlborough, MA (US);
Clarence M Sidlo, Framingham, MA (US);
Melvin J Teare, Framingham, MA (US);
Assignee:
GTE Laboratories Incorporated, Waltham, MA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
380-5 ; 380 20 ;
Abstract
A video recording medium storing a video program includes a series of television fields including a first field containing both a random digital code encrypted according to a code encryption key and program identification data, and a second field containing an unintelligible video signal previously transformed from an intelligible video signal according to the random digital code.