| 摘要 |
PURPOSE:To stably control a picture density by detecting the electric potential of a latent image by means of an electric potential sensor, and at the same time supplying developer for a reference density pattern latent image at the point of time that the detected electric potential is set at the prescribed value. CONSTITUTION:The electric potential sensor 12 for detecting an electrifying condition of a latent image carrier 1 is arranged on the same plane including the same circumference with respect to the latent image carrier 1 and an optical sensor 7 which detects the amount of developer attached to the reference density pattern latent image. The electric potential sensor 12 detects the potential of the reference density pattern latent image, and the output from the electric potential sensor 12 controls the electrifying condition of the latent image carrier 1 until the detected electric potential corresponds with the electric potential set for the reference density pattern latent image. After that, a visible picture processing is carried out with the developer, and the light reflectance of the visible picture is detected. This makes electric potential fluctuation uniform and achieves accurate setting of a developer density. |
