Four channel single photon counting module

From: Excelitas Technologies

Posted On: 05 Oct 2018

Excelitas Technologies introduces the all new high performance four channel single photon counting modules (SPCM). Excelitas Technologies is a global leader focused on delivering innovative, customised optoelectronics solutions.

Excelitas Technologies have extended it’s portfolio of low-light-level detection modules with a multi-channel version of the well-known SPCM single photon counting module that is based on a unique silicon avalanche photodiode (SLiK) that has a circular active area of 180μm with a peak photon detection efficiency exceeding 60% at 650nm. Each photodiode is both thermoelectrically cooled and temperature controlled, ensuring stabilized performance despite changes in the ambient temperature.

The SPCM-AQ4C card uses an improved circuit with a peak count rate >4 M c/s for short bursts of time on all 4 channels and a count rate of 1.5 M c/s for continuous operation. There is a “dead time” of 50 nanoseconds (ns) between pulses. The module requires +2 Volts, +5 Volt, and +30 Volt power supplies. The output of each channel – a TTL pulse that is 4.5 Volts high (into a 50 Ω load) and 25 ns wide – is available at the card edge behind the circuit board. Each TTL pulse corresponds to a detected photon.