Calibration of detection efficiency and of deadtime of of single-photon detectors InGaAs-SPAD detector: 1280 nm - 1350nm, 1450 nm to 1600 nm, other wavelengths on request. SNSPD: 1280 nm - 1350nm, 1450 nm to 1600 nm, other wavelengths on request. Photon flux level: dark count level up to saturation. Applications for quantum light sources are: Quantum Communication and Quantum Key Distribution (QKD). For further details, please contact us.