Photostimulated luminescence

Photostimulated luminescence (PSL) is the release of stored energy within a phosphor by stimulation with visible light, to produce a luminescent signal. Commonly this is used to allow the storage of a weak radioactive signal in a phosphor plate that takes the place of X-ray film, potentially over a prolonged period, which PSL transforms to obtain a highly sensitive image of the original pattern of radiation. Also known as an image plate, a photostimulable phosphor (PSP) plate can be used to record a two-dimensional image of the intensity short-wavelength (typically, X-ray) electromagnetic radiation. The device to read such a plate is known as a phosphorimager (occasionally spelled phosphoimager, perhaps reflecting its common application in molecular biology for detecting radiolabeled phosphorylated proteins and nucleic acids).