| 摘要 |
PURPOSE:To obtain a toner residual quantity detector without malfunction by converting a signal outputted from an amplifier part to an integral waveform. CONSTITUTION:The light emitting signal of a light emitting part 1 is detected with a light receiving part 3, and is amplified to a waveform 8 as shown in figure with the amplifier part 4. Also, the light emitting part 1 emits light in pulse shape like a waveform 5, and the signal transmits even when a stain exists at a measuring part 2, and arrives at the light receiving part 3. At such a case, the waveform 8 is integrated with an integrator 7, and is converted to a detection signal as shown in a waveform 9, and the signal is outputted as the detection signal. At this time, the level B of the detection signal goes higher than the level A of an amplification signal by using an integration circuit, and a noise-resistant margin can be expanded, which reduces the malfunction due to the noise. Thereby, it is possible to accurately detect the presence/absence of toner residual quantity, and to prevent the malfunction of a circuit due to the noise occurring with simple configuration. |
