PRINT DENSITY CONTROL FOR PRINTER

摘要

PURPOSE:To enable the printing at an appropriate density by controlling the pulse width or the amplitude to a dot heat generating body according to the temperature of a thermal head and the color of an ink in a heat transfer type color printer. CONSTITUTION:An MPU circuit 4 detects ink color on an ink donor sheet 2 with an ink donor sheet color detection circuit 1 and the temperature of a thermal head 3 is detected with a thermistor 3d on the thermal head 3. Then, the printing pulse width is calculated and set corresponding to the color and the temperature based on characteristics of the thermal head temperature and the printing pulse width varied according the predetermined ink color and the printing pulse with the same pulse width is applied to a dot heat generating body 3c of the thermal head 3 until printing of one color ends. This enables a printing at an appropriate density while generating no jarring peeling sound.