| 摘要 |
<p>PURPOSE:To prevent the occurrence of printing density irregularity by providing many dummy resistors and their drive circuit for thermal resistance elements and driving the dummy resistors using the inverted input data. CONSTITUTION:Many thermal resistance elements R1-Rn and their drive circuits D1-Dn are connected in parallel to a power supply PW, and the thermal resistance elements R1-Rn are driven through the drive circuits D1-Dn based on entered data. In a thermal head with the above function, many dummy resistors R1'-Rn' corresponding to the thermal resistance elements R1-Rn and their drive circuits D1'-Dn' are provided. The dummy resistance elements R1'-Rn' are driven using the inverted input data. Consequently, the number of driven resistor groups including the dummy resistors R1'-Rn' is the same as that of the thermal resistance elements R1-Rn regardless of the driven number of the latter in accordance with a printing pattern. Therefore, no density difference due to the number of the driven thermal resistance elements R1-Rn occurs.</p> |
