| 摘要 |
PURPOSE:To enable density control without releasing a density controller when high or low density is needed, by forming a target composed of plural segments of liquid crystals, and selectively blackening it in accordance with set density. CONSTITUTION:A liquid crystal target T is composed of a larger segment (a), and smaller segments (b), (c), and fixed to a platen 14. A density detection sensor 46 is arranged downstream from a developing device 36. In normal copying, the segments (a), (b) are blackened, a toner density obtained from this latent image is detected and the density is controlled with a controller 50. When a high density copy is needed, only the segment (a) is blackened and developed, but the target image is composed of only the segment (a) so it is small, the detection density does not become extremely high, and the desired high density image is obtained. When a low density image is needed, the segments (a), (b), (c) are blackened. As a result, density can be controlled without separating the density controller. |
