Estimation of extrinsic detection efficiency using intrinsic detection sensitivity of the commercial single photon detector

The detection efficiency ($DE$) of the commercial single-photon-receiver based on InGaAs gate-mode avalanche photodiode is estimated using the detection sensitivity ($DS$). Instalment of a digital-blanking-system (DBS) to reduce dark current makes the difference between $DS$, which is an efficiency of the detector during its open-gate/active state, and the total/overall detection efficiency ($DE$). By numerical simulations, it is found that the average number of light-pulses, blanked by DBS, following a registered pulse is 0.333. $DS$ is estimated at 0.216, which can be used for estimating $DE$ for an arbitrary photon arriving rate and a gating frequency of the receiver.