| 摘要 |
PURPOSE:To control the recording density by detecting the concentration of a developer on a photoreceptor. CONSTITUTION:A concentration detector 3 is a photointerrupter constituted of a photodiode and a phototrasistor. The detector 3 is held by a shaft 24 and moved in the direction of B by a wire 21 when a motor 20 is rotated. At this time, the concentration is detected with reflected light from a black solid developed image 23 previously formed on the photoreceptor 1. A prescribed CPU controls the concentration of the developer stuck to the photoreceptor 1 to obtain an appropriate recording density based on the result of the detection. |
