| 摘要 |
PURPOSE:To correct a scatter in each output characteristic of a sensor to be adjusted and increase an accuracy in the predetermined output of the sensor by so controlling the output of the sensor (a density sensor) to be adjusted that the output agrees with an output characteristic as that of a reference sensor stored in storage means. CONSTITUTION:A developer that represents a first (second) reference condition is set anda first (second) reference voltage 21(22) that is the output of a reference sensor having a predetermined output characteristic for the first (second) reference density P1 (P2) corresponding to the first (second) reference condition is stored. On the other hand, the output 24 of a density sensor is level-shifted to be made agree with a line 25. This makes the output 24 equal to the first reference voltage value 21 corresponding to the density P1. Then, the inclination of the above-described, level-shifted output of the sensor is so changed that the voltage of the sensor output shown by a line 25 and corresponding to the density P2 is equal to the second reference voltage value 22, agreeing with the inclination of a final target characteristic 23. On the basis of the sensor output thus adjusted, control signals from a processing circuit are supplied to a driving circuit, a development bias control circuit, a discharge voltage control circuit and a lamp control circuit, and driving a toner motor and the like are controlled to obtain a copied image with a good image density. |
