photomultiplier

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Related to PM tube: Photomultiplier Tube

photomultiplier:

see photoelectric cellphotoelectric cell
or photocell,
device whose electrical characteristics (e.g., current, voltage, or resistance) vary when light is incident upon it. The most common type consists of two electrodes separated by a light-sensitive semiconductor material.
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photomultiplier

(foh-toh-mul -tă-plÿ-er) (photomultiplier tube; phototube) An electronic device used to convert a low-intensity light signal into an electrical signal and to amplify this signal very considerably. It contains a photocathode from which electrons are liberated by the incident light photons. The electrons are accelerated down an evacuated tube by a series of positively charged electrodes to which an increasingly high potential is applied. At each electrode a number of additional electrons are released by each impacting electron (by secondary emission). The electrons are all collected at the final electrode in the chain, which is held at a very high potential, and a large current pulse is produced.

photomultiplier

[¦fōd·ō′məl·tə‚plī·ər]
(electronics)