04218698 is referenced by 275 patents and cites 3 patents.

A system employed in a television receiver for decoding and displaying graphics information such as may be encoded on a broadcast video signal. The system includes a graphics signal decoder supplied with the encoded video signal, and a plurality of transmission gates responsive to logic control signals derived from outputs of the decoder. The gates are coupled to inputs of video output stages in the receiver, and operate in response to the control signals for interrupting normal video signals to the video output stages and for enabling a voltage representative of a graphics display intensity level to be coupled to the video output stages when graphics information is to be displayed.The system also includes a graphics level control network. The level control network limits excessive graphics representative beam current levels to prevent image defocusing and kinescope screen burn. The level control network also adjusts the graphics display intensity level in accordance with the level of image representative video signals in a mixed video plus graphics display mode, to preserve a desired contrast relationship between the displayed video and graphics information.

Title
TV Graphics and mixing control
Application Number
6/24151
Publication Number
4218698
Application Date
March 6, 1979
Publication Date
August 19, 1980
Inventor
Ronald A Mills
Kusnacht
CH
Theodor E Bart
Zurich
CH
Agent
Ronald H Kurdyla
W H Meagher
Eugene M Whitacre
Assignee
RCA Corporation
NY, US
IPC
H04N 5/22
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