Princeton Lightwave Inc. has introduced a single-photon-counting benchtop receiver for wavelengths from 1.0 to 1.5 μm. It can operate from either the internal frequency generator or from an external trigger at rates of up to 20 MHz. Parameters such as bias voltage, single-photon-counting avalanche photodiode temperature, trigger delay and measurement interval are controlled from the front panel or through the RS-232 interface. The instrument displays the number of photons detected and the number of trigger pulses in a user-defined interval. Minimum detection efficiency is ≥25%, and typical dark count rate is 2 × 10–5 per trigger when the benchtop is operated with a 1-ns gate and 20% detection efficiency.