A thermal head has plural heat generating elements arrayed therein in a main scanning direction to form a heat generating element row, causes the respective heat generating elements to generate heat while conveying a recording medium in a sub-scanning direction, and forms plural dot lines in the main scanning direction on the recording medium to record an image. A plurality of the heat generating element rows are arrayed in the sub-scanning direction. Respective nth (n is a natural number) heat generating elements among the heat generating elements in the respective heat generating element rows can sharingly form a dot in the same position in an identical dot line according to independent driving for each of the heat generating element rows.