| 摘要 |
PURPOSE:To prevent the edge effect when a density controlling mark is formed, by using an auxiliary mark having a narrow area. CONSTITUTION:In case that an image is exposed to a photosensitive drum 1 by an exposure means 3, a reference pattern 12 is projected to the outside of the image part. The toner density of a pattern 12 developed by a developing equipment 4 is detected by a detector 10 to control the toner supply quantity. A density control mark 12-2 has a high density in leading and trailing edges because of the edge effect and is apt to be white in the center part, and this mark 12-2 does not indicate the toner density correctly. Therefore, an auxiliary mark 12-1 having a narrow area is provided to obtain the mark without the edge effect. |
