Accumulated heat correction method and apparatus

摘要

Accumulated heat correcting data of an Nth line to be printed is subtracted from original heat data of the Nth line. This corrected heat data of the Nth line is supplied to a head driver which drives a thermal head to record dots of one line on a recording sheet. The corrected heat data of the Nth line is multiplied by a coefficient K1 to obtain first data. The first data is added to the accumulated heat correcting data of the Nth line, and sum data of the addition is written in a line memory as second data. In printing the (N+1)th line, the second data is read from the line memory. The second data is multiplied by a coefficient K2 to obtain the accumulated heat correcting data of the (N+1)th line, which is used for accumulated heat correction of the original heat data of the (N+1)th line.