| 摘要 |
PURPOSE:To always obtain the perfectly adjusted density of a copying machine, by controlling the density of an image corresponding to an original image so as to coincide exactly with that of a toner image transferred on a copying sheet actually. CONSTITUTION:In the copying machine, the picture density of an original is detected by performing the exposure scan of the original by a light source, and passing the beam of light having intensity corresponding to the variable density of the original image through a picture density detecting sensor 7. Also, an electrostatic latent image corresponding to the original image is formed on the surface of a photosensitive body by the beam of light passing the picture density detecting sensor 7, and toner is attached on the image at a developing part, then, the toner image can be formed. The picture density of an obtained toner image is detected with a toner density sensor 11. Thus, the picture density based on the intensity of the beam of light on the same part of the image and a toner density signal based on the attached quantity (variable density) of the toner can be obtained, and they are compared, then, a toner density adjusting means such as a toner refilling motor 16, etc., is driven so as to reduce a difference between them, and thereby, correspondence relation between the picture density and the toner density can be maintained constant invariably. In such way, it is possible to adjust the density of the toner image exactly. |
