| 摘要 |
PURPOSE:To measure toner adhesive quantity on an image carrier in the area of high toner adhesive quantity where the sensitivity of a photodetecting element is low. CONSTITUTION:The surface potential of the electrostatic latent image of a gradation density pattern is detected and continuously the reflected light quantity of the visible image of the gradation density pattern is measured. Based on the surface potential in the range of the reflected light quantity where the sensitivity of the photodetecting element 208 is excellent and the toner adhesive quantity obtained from the reflected light quantity corresponding to the surface potential, a relational expression between the surface potential and the toner adhesive quantity is obtained. In the range of the reflected light quantity where the sensitivity of the element 208 is excellent, the toner adhesive quantity is operated from the reflected light quantity, and in the range of the reflected light quantity where the sensitivity of the element 208 is lowered, the surface potential of the electrostatic latent image of the gradation density pattern and the relational expession between the surface potential and the toner adhesive quantity are used to operated the toner adhesive quantity. |
