photon counting

Also contains definition of: single-photon counting
Recording of sequential single photons counted by way of recording and counting sequential electron pulses at the anode of the photomultiplier.
  1. Each electron pulse consists of 105–106 electrons resulting from the multiplication, in the 'dynode' arrangement (or the microchannel plate) of a photomultiplier, of a single photoelectron emitted by a photosensitive layer (the photocathode of the photomultiplier) upon arrival of a single photon.
  2. Technique used for two purposes: (i) sensitive measurement of low levels of radiation such as those originating from a luminophore and (ii) recording of emission decays.
PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 393 (