| 摘要 |
<p>PURPOSE:To stabilize the operational characteristics of a crystalline liquid optical shutter by varying an energization rate to a heating element with the help of a waveform applied to the crystalline liquid optical shutter in an apparatus for controlling the temperature of a heating element provided on a crystalline liquid optical shutter by energization control. CONSTITUTION:A single pulse is output from 'AND' circuit 24 each time printing is performed in black dots, and the black dots are formed by applying a frequency fH. An output from the AND circuit 24 is counted in dots by means of a 1/2<8> frequency dividing circuit 25 and a counter circuit 26, and a correction value of an energization rate to a heater 22 is calculated by an arithmetic circuit 28 according to the above-mentioned number of black dots. This correction signal is output to a PWM temperature regulator circuit 30. This circuit 30 is synchronized to a clock signal from a printer control circuit 27, and also controls the energization of the heater 22 through an inverter 31 from a detection value of a thermistor 23. At that time, the circuit 30 changes a duty with a drive signal to the shutter, corrects a self-heating amount and stabilizes the temperature to 45 deg.C.</p> |
