| 摘要 |
PURPOSE:To carry out the information detection of a rotary body with a simple constitution by arranging a mark for forming first and second regions at a ratio corresponding to the characteristics of the rotary body in the rotational direction of the rotary body, and identifying, detecting, and integrating it. CONSTITUTION:When a photosensitive drum 1 is rotated, and reading is started by a photosensor, a voltage signal which is made high in a white part 2, and low in a black part 3, is obtained, and outputted to an integration circuit 6. Therefore, a capacitor C1 is charged for the reading period T1 of the white part 2, while it is discharged for the reading period T2 of the black part 3. The voltage of the capacitor C1 is stabilized by a voltage V1 corresponding to the ratio of the width of the white part 2 and the black part 3. The voltage V1 is amplified by an amplifier 7, and outputted into a control system. Thus, the ratio of the width of the white part 2 and the black part 3 is set according to the characteristics of the photosensitive drum 1, so that a detection level can be set, and a hard, or soft constitution can be simplified. |
