Thermal recording apparatus with a thermal head including energizing time controlling

摘要

A thermal recording apparatus includes a thermal head. Printing for multi-tone density is performed by changing an energizing time of the thermal head. The apparatus has a controller for controlling the energizing time and an interrupting circuit. The controller controls the energizing time to match to a value corresponding to a tone density for printing. The interrupting circuit puts an interrupt period of energizing for the energizing time if the energizing time is equal to or more than a predetermined time. A plurality of different counters is provided for increasing the interrupt period in duration stepwisely.