| 摘要 |
<p>PURPOSE:To enable the recording of a high quality image free of scrutching and trailing with an improved heat response of a heat generating body by running to the heat generating body of a thermal head a pulse current sharply rising up to the max. value and damping in the time elapsed. CONSTITUTION:A negative recording pulse current is applied to a terminal 4 to turn ON a transistor 2, a voltage of a recording power source 3 is applied to a heat generating body 1 and a differentiation circuit comprising a capacitor 7 and simultaneously with turning ON thereof, a current flows to the heat generating body 1 in such a manner as to rise sharply and then damp along the time constant curve of the differentiation circuit. Therefore, the temperature waveform of the heat generating body 1 also rises sharply and then falls gradually, with the result that the temperature of the heat generating body 1 comes down low sufficiently at the time when the recording pulse is turned OFF. Thus, phenomenon such as scrutchint and trailing of the recording image becomes hard to occur thereby enabling the recording of a high quality image even in a high-speed thermal recorder with a short recording pulse width.</p> |
