photomultiplier tube

pho·to·mul·ti·pli·er tube .fōt-ō-'məl-tə-.plī(-ə)r- n a vacuum tube that detects light esp. from dim sources through the use of photoemission and successive instances of secondary emission to produce enough electrons to generate a useful current called also photomultiplier

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an electronic device that magnifies the light emitted from a scintillator by accelerating electrons in a high-voltage field. The resulting signal can be used to display the scintillations on a TV screen. Such devices are commonly used in gamma camera.

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a vacuum tube that converts electromagnetic radiation signals into electrical pulses, consisting of a light-sensitive surface that emits electrons when light is incident on it, the electrons then passing through successive stages with electron multiplication at each stage.