| 摘要 |
PROBLEM TO BE SOLVED: To accurately detect a developer amount in a developer container even when the scattering or the leakage of developer causes contamination due to the adhesion of the developer in a light passing path in a system detecting the developer amount in the developer container according to light transmissivity to the developer in the developer container. SOLUTION: This detecting device is provided with a bottom hold part 1 storing the maximum value of the intensity of detected light by a photodetector in a specified time, and an automatic threshold setting part 2 setting a threshold so that the rate of the maximum value stored in the bottom hold part 1 to the threshold may be a specified value. Then, a comparator waveform shaping part 3 compares the threshold set by the setting part 2 with the intensity of the detected light by the photodetector. |
