| 摘要 |
<p>Photon detecting apparatus and method capable of simply and easily suppressing afterpulse noise of the photon detecting apparatus without performing a charge pulse elimination of an avalanche photodiode. The photo detecting apparatus comprises photon detecting means using an avalanche photodiode as a light receiving element; a bias tee for applying a voltage to the avalanche photodiode; a DC voltage generator for applying a DC voltage, as a bias voltage, to the bias tee; a voltage pulse generator for applying a pulse voltage to the bias tee to cause the detecting means to operate only at a scheduled photon detection time; and a pulse-amplitude discriminator for determining whether any photon has been detected. The DC voltage generator is adapted to generate the DC voltage that is lower than the breakdown voltage of the avalanche photodiode. A narrow-width voltage pulse generated by the pulse generator at a scheduled photon arrival time is superimposed on the DC voltage via the bias tee, thereby applying the summed voltage, which comprises the DC voltage and the voltage pulse, to the avalanche photodiode.</p> |
