CATHODE RAY TUBE HAVING AUXILIARY DEFLECTION PLATE TO CORRECT PINCUSHION DISTORTION

摘要

A cathode ray tube having two electron beams and associated deflection systems is described in which an auxiliary deflection plate is employed between two pairs of vertical deflection plates at their outputs to correct pincushion distortion. A correction signal is produced by a control circuit and applied to the auxiliary deflection plate in response to a ramp voltage input corresponding to the horizontal sweep signal. The correction signal is a positive going peak shaped voltage so that the auxiliary deflection plate tends to vertically deflect the beams away from such plate at both the start and end of the horizontal sweep signal to correct pincushion distortion while not deflecting such beam appreciatively at the center of such sweep signal.