| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device capable of preventing an image from being soiled because of filming by detecting the filming. SOLUTION: The quantity of light radiated from the LED 41a of a reflection type sensor 41 and reflected on the surface of a photoreceptor drum 30Y is detected by a phototransistor 41b. When the filming is caused on the drum 30Y, the detected value of the reflected light quantity becomes small because the light radiated from the LED 41a is diffused on the surface of the filming. In the case of judging that the filming occurs by comparing the detected value with a reference value, the operation of a copying machine is stopped. |
