  We demonstrate an integral gated mode single photon detector at telecom
wavelengths. The charge number of an avalanche pulse rather than the peak
current is monitored for single-photon detection. The transient spikes in
conventional gated mode operation are canceled completely by integrating, which
enables one to improve the performance of single photon detector greatly with
the same avalanche photodiode. This method has achieved a detection efficiency
of 29.9% at the dark count probability per gate equal to 5.57E-6/gate
(1.11E-6/ns) at 1550nm.
