03993861 is referenced by 97 patents and cites 8 patents.

In a television system, a digital video system permits the transmission of data along with the usual television picture. The television picture field includes one or more selectively addressable areas and the data is imprissed on these areas as digital, binary-coded brightness modulations at rates greater than the vertical field rate. At the receiving end of the system, the viewer positions one or more light sensors opposite these screen areas. The light sensors respond to the binary-coded brightness modulations by developing corresponding binary-coded digital electrical signals. The data stream from a light sensor can then be decoded by a demodulator/decoder operated by the viewer.

Title
Digital video modulation and demodulation system
Application Number
5/561131
Publication Number
3993861
Application Date
March 24, 1975
Publication Date
November 23, 1976
Inventor
Ralph H Baer
Manchester
NH, US
Agent
Richard I Seligman
Louis Etlinger
Assignee
Sanders Associates
NH, US
IPC
H04N 7/00
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