| 摘要 |
A photodetecting device 1 includes a photodiode PDm,n, a switch SWm,n for the photodiode, an integrating circuit 12m, and a noise removing circuit 13m. The integrating circuit 12m accumulates in a capacitor Cfk an electric charge input from the photodiode PDm,n through the switch SWm,n for the photodiode, and outputs a voltage value according to the amount of the accumulated electric charge. The noise removing circuit 13m includes an amplifier A3, five switches SW31 to SW35, four capacitors C31 to C34, and a power supply V3. The noise removing circuit 13m takes in a voltage value that is output from the integrating circuit 12m at a time where the switch SW31 is first turned from a closed state to an open state, and after the time, outputs a voltage value according to a difference between the voltage value that is output from the integrating circuit 12m and the voltage value previously taken in.
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