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US 4,731,565 AGranted
High voltage generator for television apparatus
AssigneeSony Corporation
InventorsSusumu Tagawa, Chihiro Miura
Life of this patent
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AssigneeSony Corporation
InventorsSusumu Tagawa, Chihiro Miura
Estimating the term…
A high-voltage stabilizer circuit cooperates with the flyback transformer in a cathode ray tube display system to prevent level variations in the video signal from producing corresponding variations in the high-voltage output from the flyback transformer to the cathode ray tube, such high-voltage variations being undesirable because they result in changes in the electron beam position on the phosphor screen that produce shifts in the resultant picture. The current flowing through the video circuit is controlled inversely in relation to variations in the cathode current of the cathode ray tube so that the high-voltage output from the flyback transformer remains constant. This high-voltage stabilizer involves specific choices of circuit element values and is particularly suitable for so-called flat-tube television receivers.
In a video display device, the combination of a cathode ray tube having a cathode, a video output circuit, a flyback transformer producing at respective secondaries a high voltage fed to said cathode ray tube and a low voltage fed to said video output circuit that also receives a video signal and provides a first current varying in response to variations in said video signal for driving said cathode of the cathode ray tube, and circuit balancing means connected between said flyback transformer and said video output circuit for changing the total current flowing in said video output circuit by supplying a second current to said video output circuit to be added to said first current, said total current changing in an inverse relationship relative to changes in the cathode current of the cathode ray tube caused by the video signal such that the high voltage is maintained constant and is fed to said cathode ray tube in spite of variations in the cathode current of said cathode ray tube.
In a video display device, the combination of a flat-type cathode ray tube having a cathode, a video output circuit, a flyback transformer producing at one secondary a high voltage fed to said cathode ray tube and at another secondary a low voltage fed to said video output circuit that also receives a video signal and provides a first current varying in response to variations in said video signal for driving said cathode of said cathode ray tube, and circuit balancing resistance element means connected to receive said low voltage form the flyback transformer and being connected to said video output circuit for controlling current flow through the latter by supplying a second current to said video output circuit to be added to said first current, said current flowing through video output circuit changing in inverse proportion to changes in the cathode current of the cathode ray tube resulting from the video signal such that the high voltage produced by the flyback transformer is maintained constant and is fed to said cathode ray tube during said changes in cathode current of the cathode ray tube.
Dependencies are inferred from the claim text.