| 摘要 |
PURPOSE:To record with favorable image quality even in the case of a high driving force or a high-resolution head, by a method wherein the width of pulses impressed on each heating resistor is controlled to an appropriate value determined in consideration of the past thermal hysteresis for each printing dot. CONSTITUTION:A calculating circuit 6 forms information for each printing dot from an image signal S inputted together with a time series of luster scanning. A temperature predicting calculating circuit 6b for calculating the heat accumulation condition of each heating resistor by using a three-dimensional heat conduction equation performs calculations for predicting the temperature in the next period from the combination of the temperature stored in a temperature memory 6d and the width of an output pulse from a pulse width calculating circuit 6a, and the calculated value is stored into the memory 6d through a one- period delay circuit 6c. Using the temperature dependence of a color former and the three-dimensional heat conduction equation, the circuit 6a calculates an optimum heating pulse width in consideration of the thermal hysteresis from the temperature stored in the memory 6d and the image signal S, and controls the width of the heating pulse impressed on the heating resistors, based on a heat conduction theory. |
