Raster distortion avoidance arrangement
AssigneeRCA Thomson Licensing Corporation
InventorPeter E. Haferl
Life of this patent
Estimating the term…
Abstract
Organ pipes distortions, caused by parasitic ringing in a horizontal deflection current are suppressed by forming a current pulse in a current injection arrangement. The current pulse is coupled to a junction terminal between a terminal of the horizontal deflection winding where a high retrace pulse voltage is developed and a low voltage terminal of a linearity correction inductance. A high voltage terminal of the linearity correction inductance is coupled to a horizontal output transistor. The current pulse begins prior to the end of retrace and ends during the trace interval. A modulation network is coupled across the linearity correction inductance for providing a low impedance current path to the current pulse.
Claims13
A video display deflection apparatus comprising:
- a deflection winding;
- a retrace capacitance coupled to said deflection winding to form a retrace resonant circuit;
- first switching means coupled to said deflection winding for producing a deflection current and a retrace pulse voltage therein;
- an inductance coupled in a current path of said deflection current between said deflection winding and said first switching means;
- means for generating a pulse of current that is coupled to said current path via a junction terminal between said inductance and said deflection winding having both a beginning time and an end time that are closer to an instant when said retrace pulse voltage ceases than to an instant when said retrace pulse voltage begins;
- and
- an impedance coupled to said terminal for modulating a current in said inductance to form a low impedance current path such that a greater portion of said current pulse flows in said impedance and bypasses said inductance.
A video display deflection apparatus comprising:
- a deflection winding;
- a retrace capacitance coupled to said deflection winding to form retrace resonant circuit;
- first switching means coupled to said deflection winding for producing a deflection current and a retrace pulse voltage therein;
- an inductance coupled in a current path of said deflection current between said deflection winding and said first switching means;
- means for generating a pulse of current that is coupled to said current path via a junction terminal between said inductance and said deflection winding having both a beginning time and an end time that are closer to an instant when said retrace pulse voltage ceases than to an instant when said retrace pulse voltage begins;
- and
- means coupled to said inductance for modulating a current that flows in said inductance such that a ratio between said deflection current and said inductance current changes, during retrace, prior to the occurrence of said current pulse.
A video display deflection apparatus comprising:
- a deflection winding;
- a retrace capacitance coupled to said deflection winding to form a retrace resonant circuit;
- first switching means coupled to said deflection winding for producing a deflection current and a retrace pulse voltage therein;
- an inductance coupled in a current path of said deflection current between said deflection winding and said first switching means;
- means for generating a pulse of current that is coupled to said current path via a junction terminal between said inductance and said deflection winding having both a beginning time and an end time that are closer to an instant when said retrace pulse voltage ceases than to an instant when said retrace pulse voltage begins;
- and
- means coupled to said terminal for narrowing said pulse of current.
Dependencies are inferred from the claim text.