Circuit and method for correcting side pincushion distortion and regulating picture width
AssigneeTektronix, Inc.
InventorSamuel Y. Gordon
Life of this patent
Estimating the term…
Abstract
A circuit within a cathode-ray tube electromagnetic deflection system for correcting side pincushion distortion and regulating picture width independent of changes in the video line rate. The circuit employs a predistorted AC reference signal and a second DC reference signal in a closed-loop manner to cause a deflection current to describe precisely an ideal waveform defining simultaneously both pincushion correction and picture width regulation.
Claims10
A circuit within a cathode-ray tube electromagnetic deflection system for correcting side pincushion distortion and regulating picture width, said circuit comprising:
- (a) a yoke inductance;
- (b) means including a source of DC supply potential for producing a delfection current through said inductance;
- (c) means for receiving an AC reference signal representing the desired amplitude modulation of said deflection current and a DC reference signal representing the desired average peak value of said deflection current;
- (d) means responsive to said deflection current, said AC reference signal, and said DC reference signal for modulating the magnitude of said DC supply potential so as to cause the amplitude of said deflection current to follow said AC reference signal and the average peak value of said deflection current to follow said DC reference signal.
A method within a cathode-ray tube electromagnetic deflection system for correcting side pincushion distortion and regulating picture width, said method comprising the steps of:
- (a) providing a yoke inductance within said electromagnetic deflection system;
- (b) producing a deflection current through said inductance, said deflection current being a function, inter alia, of a DC supply potential;
- (c) receiving an AC reference signal representing the desired amplitude of said deflection current;
- (d) receiving a DC reference signal representing the desired average peak value of said deflection current;
- and
- (e) responsive to said deflection current, said AC reference signal, and said DC reference signal, modulating the magnitude of said DC supply potential so as to cause the amplitude of said deflection current to follow said AC reference signal and the average peak value of said deflection current to follow said DC reference signal.
Dependencies are inferred from the claim text.