SEARCH Articles Figures Tables Classification and Phenomenological Descriptions of Selected Photon Detection Mechanisms Detection fluorescence photons Direct Photon Detection Multifrequency Single-Photon Selective Heterodyne Radiometry for Detection of Remote Species On Specific Detectivity of Photonic Infrared Detectors Other Photon-detecting Techniques Photon burst detection Photon detection Photon detection statistics Photon detection statistics fluctuations Sampled single-photon detection Signal-to-Noise Ratio and Minimum Detectable Number of Photons Single photon counting detection Single-photon fluorescence steady-state detection Single-photon fluorescence time-resolved detection Spectroscopy based on photon detection Three-Frequency Single-Photon Heterodyne Detection Using a Nonlinear Device