Optical photon counter SPCM-AQ4C

high-sensitivity

Overview
The SPCM-AQ4C is a four-channel photon counting module for single-photon detection across the 400–1060 nm range. Each channel operates independently and provides discrete TTL pulses corresponding to detected photons.

Key features and functional description
The module integrates four SLiK silicon avalanche photodiodes with 180 μm circular active areas and peak photon detection efficiency >60% at 650 nm. Each APD is thermoelectrically cooled and temperature-controlled to maintain stable performance. High-speed front-end electronics deliver peak burst count rates >4M counts/s on all channels and a continuous count rate of 1.5M counts/s, with a 50 ns dead time between pulses. Outputs are standard TTL pulses (4.5 V high into 50 Ω, 25 ns wide) accessible at the card edge / connector. FC fiber connectors are mounted and aligned on each detector. The module is self-contained with integrated APD electronics and is RoHS compliant.

Applications / Use

• Single-photon detection from visible to near-infrared (400–1060 nm)
• Multi-channel photon counting in compact, integrated packages (four independent channels)
• Measurements requiring temperature-stabilized APDs and high peak count capability

Specifications

• Wavelength range: 400 nm to 1060 nm
• Detector type: Silicon avalanche photodiode (SLiK)
• Active area: 180 μm diameter (circular)
• Peak photon detection efficiency at 650 nm: 60% typical
• Afterpulsing probability: 0.5%
• Gated input: supported
• Output: TTL pulses (4.5 V high into 50 Ω, 25 ns wide)
• Peak count rate: >4M counts/s for short bursts (all four channels)
• Continuous count rate: 1.5M counts/s
• Dead time between pulses: 50 ns
• Power supply requirements: +2 V, +5 V, +30 V
• FC fiber connector mounted and aligned on each detector
• Four channels integrated in one package
• Self-contained APD module with integrated electronics
• All input and output signals available at card connector
• Thermoelectric cooling and temperature control for each photodiode
• RoHS compliant