| 摘要 |
PURPOSE:To always obtain an image with excellent image quality even when a copying machine is used by any magnification within the range of variable power by providing patterns for a potential sensor and for a toner sensor and specifying the positions of the potential sensor and the toner sensor and the positions of the respective patterns. CONSTITUTION:The potential sensor 20 which detects the surface potential of a photosensitive body, the toner sensor 17 which detects the density of a toner image formed on the photosensitive body and the respective patterns 21a and 21b for the potential sensor and the toner sensor which are arranged at a right angle to the carrying direction of a paper by being closely brought into contact with a specified corner on an original platen other than an original surface are provided. Then, the sensors 20 and 17 are disposed so that the components of a right angle direction to the carrying direction of the paper at the respective positions of the sensors 20 and 17 mutually become different. Besides, the pattern for a potential sensor 21a is arranged at such an area that it is projected on a position within the range of the variable power and corresponding to the sensor 20 and the pattern for a toner sensor 21b is arranged at an area other than it. Thus, the image with the excellent image quality is always obtained even when the copying machine is used by any magnification within the range of the variable power. |
