| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device surely performing form detection on a photoreceptor independent of an internal temp. change due to a use environment and a continuous use. SOLUTION: A temp. detection means 308 is provided in the vicinity of a sensor part 3010 detecting reflection beam intensity, and detects the temp. in the vicinity of the sensor part from a voltage Vr outputted from the sensor part 3010 according to the reflection beam intensity and the output voltage Vt of the temp. detection means 308, and sets a threshold Vth suited to the detected temp. in a comparator 306. The comparator 306 compares the threshold Vth with the output voltage Vr of the sensor part 3010, and makes an output signal Ij into a high level when Vr>Vth. The output signal Ij is inputted to an input port of an I/O port 116, and a CPU 111 monitoring the input port recognizes the form detection. |
