| 摘要 |
PURPOSE:To minimize the number of basic data, required for a convergence shift correction, into the necessary minimum by constituting an equipment so that a correction data for correcting the convergence shift of a scanning line, is grasped as a function value, determined according to a value, which is optimum-set at the time of a convergence adjustment, and to a deflection scanning position. CONSTITUTION:This circuit 11 is provided with a coefficient storage circuit 12, which stores the weighting coefficient of respective basic correction waves, at the time when the correction data is grasped as a synthesized wave (correction function) of the basic correction wave in a horizontal scanning period or a vertical scanning period, and a correction data storage circuit 13, which stores the correction data, calculated by using a coefficient to be read out from the storage circuit 12, for every sampling point to divide a picture frame in a matrix shape, and an read address generation circuit 15, which designates a necessary address for reading out the correction data from the storage circuit 13, and so on, and a remaining period, excluding an access period to the correction data storage circuit 13 by a central processing unit 14, is assigned to the read-out address generation circuit 15 as an address designating period, by every small period, that one horizontal scanning period is divided according to the number of the sampling points, and besides, this period is made to be a fixed period, which is never varied by a horizontal deflection frequency.
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