METHOD AND DEVICE FOR REGULATING RESISTANCE VALUE OF HEATING RESISTOR OF THERMAL HEAD MOUNTED WITH DRIVER IC

摘要

PURPOSE:To avoid influence to a thermal head through dispersion of resistance of a driver IC by mounting the driver IC and that to a surface temperature of the thermal head by the thickness of an overcoat layer. CONSTITUTION:A surface temperature of the upper part of an overcoat of a thermal head 20 to which a driver IC is mounted is measured by an infrared microscope 14 and in the case where a measured value is out of a range of a preestablished value, laser having an irradiation length corresponding to the measured value is applied to a resistor by a laser irradiation apparatus 18 through a computer 22. Then irradiation of the laser to the resistor is repeated until the measured value of the surface temperature attains the preestablished value and a resistance value of the heating resistor is allowed to change. Since the surface temperature of the thermal head to which the driver IC is mounted is made uniform, influence to the surface temperature of the thermal head by dispersion of the resistance values through mounting the driver IC and a thickness of an overcoat layer can be avoided.