photon counting

see also:

single-photon detectors, SPD, detection of individual photons, photosensors, multi-pixel photon counter

In single-photon counting, a single-photon detector (SPD) emits an electric pulse every time a photon is detected so that individual photons can be counted. Photon counting is used in telecommunication, biophysics imaging (e.g. FLIM), quantum optics and high-resolution (single-pixel) LIDAR, OTDR (optical time-domain reflectometry) and Quantum Key Distribution (QKD).

photon counting