| Photomultipliers |
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| Photomultiplier tubes (photomultipliers or PMTs, for short)—members of the class of vacuum tubes and more specifically phototubes—are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum. These detectors multiply the current produced by incident light by as much as 100 million times, in multiple dynode stages, enabling individual photons to be detected when the incident flux of light is very low. |