photomultiplier

[ foh-tuh-muhl-tuh-plahy-er ]

noun

1. an extremely sensitive detector of light and of other radiation, consisting of a tube in which the electrons released by radiation striking a photocathode are accelerated, greatly amplifying the signal obtainable from small quantities of radiation.

photomultiplier

/ ˌfəʊtəʊˈmʌltɪˌplaɪə /

noun

1. a device sensitive to electromagnetic radiation, consisting of a photocathode, from which electrons are released by incident photons, and an electron multiplier, which amplifies and produces a detectable pulse of current

photomultiplier

/ fō′tō-mŭl′tə-plī′ər /

1. An electrical device designed for the detection of weak electromagnetic radiation, usually light, by amplifying the energy of the photons that strike it into stronger electrical signals. Photomultipliers are used in night-vision technology and in telescopes to detect light not strong enough to be visible by the unaided eye.
2. ◆ The most common photomultiplier is the tube photomultiplier ; it exploits secondary emission of electrons in a vacuum tube in the manner of an electron multiplier. When radiation strikes the cathode of a tube photomultiplier, electrons called photoelectrons are emitted and attracted to positively charged electrodes called dynodes. When they collide with the dynode, more electrons are released; these are in turn attracted to another dynode at a higher voltage to release yet more electrons, and so on. At the end of this process, there is a current flow at the anode that is strong enough to be easily detected.

Word History and Origins

Origin of photomultiplier¹

First recorded in 1935–40; photo- + multiplier

Example Sentences

"The speed of mosTF is still limited by needing to use high sensitivity, low noise cameras that are often slow. We are now working on a next generation system with new type of detectors such as hybrid photomultiplier or avalanche photodiode arrays that are both sensitive and fast."

From Science Daily

The photons are captured by a detector, which in this case is essentially a cylindrical crystal with a photomultiplier tube that passes the light signal to the data acquisition system.

From Science Daily

And industrial partners boosted the sensitivity of the 43,000 photomultiplier tubes arrayed around the sphere that detect the pulses.

From Science Magazine

The ice provides enough mass so that one out of every million neutrinos passing through will hit something, releasing a flash of light that can be captured by more than 5,000 photomultiplier tubes frozen into the ice.

From New York Times

Then they tracked the resulting annihilation radiation at the farthest edges of their experiment, using two photomultiplier tubes, anthracene crystals and a scintillation counter as a gamma-ray detector.

From Scientific American