| 摘要 |
<p>PURPOSE: To dispense with the time required in trimming processing and to adjust the minute resistance value in the vicinity of an objective resistance value by adjusting pulse width in such a state that electric energy is fixed until a resistance value reaches an objective resistance value after resistance difference reaches a constant value. CONSTITUTION: Heating elements 12 are formed on a substrate 11 composed of an insulating substrate in one row by membrane technique. At the time of trimming processing, rough adjusting processing increasing the electric energy of a trimming pulse is performed in order to shorten a trimming processing time until the difference between the resistance value of the heating elements 12 and an objective resistance value becomes a constant value. After the resistance value reaches the constant value, pulse like power is applied to the arbitrary heating element 12 while pulse width is adjusted in such a state that electric energy is fixed until the resistance value of the arbitrary heating element 12 reaches the objective resistance value. By this constitution, the resistance value of the heating elements 12 can be accurately set to the objective resistance value and the irregularity of image density generated by the irregularity of a resistance value is prevented to obtain a good image.</p> |
