| 摘要 |
<p>PURPOSE:To prevent concentration of generated heat at a crossing section, maintain the reliability of a thermal resistor in satisfactory condition for a long time and thereby make an image sharp by turning power ON in two energization paths at which the thermal resistor crosses at a varying time. CONSTITUTION:Flat X-shaped thermal resistors 4 are aligned with insulating materials 6 which partition each thermal resistor, on an insulating substrate 2. Electrodes 8 are arranged for each thermal resistor 4 at their respective ends. A pulsed voltage is applied to each energization path 4a, 4b for thermal resistor 4 at a varying time using a power supply control device. A pulse P is set by dividing time (t) with (n) (n>=2), given (t) as a printing time for a single dot, as time interval for applying the pulsed voltage to the energization path 4a. In addition, the pulse P is set for the energization path 4b at the same time interval and in such a manner that the pulse is not applied to the energization path 4a at the same time. Thus it is possible to prevent concentration of generated heat at the crossing section 4c at which the thermal resistor 4 crosses. As a result, dots (d) in the form of almost completely perfect circle and without density irregularity can be obtained.</p> |
