| 摘要 |
<p>PURPOSE:To perform beautiful printing having uniform density by operating the heat value, quantity of radiation and heat exchange quantity of each element divided into a plurality of elements to calculate temp. after the supply of a current at every one dot and controlling the current supply energy of the next time. CONSTITUTION:An MPU 15 performing control is provided to a control block. At first, the initial temp. value of each element such as environmental temp. or the temp. of a radiation plate is set and, on the basis of this initial value and the ON/OFF data of each heating element 12 of a thermal head 7 from the MPU 15, the heat value of each element is calculated by a heat value adding part 17. Next, a change of heat energy distribution due to heat exchange between respective elements is calculated by a heat diffusion quantity calculation part 18 and the present temp. of each element is calculated by an element temp. calculation part 19. This temp. of each element is sent to an element temp. memory part 16 to be stored therein and also sent to a current supply time calculation part 20 and the proper current supply time of a heating element 12 turned ON next is set to perform proper current supply control by a current supply control part 21. As a result, beautiful printing having uniform density is obtained.</p> |
