dynode
Quick Summary
A dynode is an electrode within an electron tube that produces secondary emission of electrons. This process is crucial in devices like photomultiplier tubes, which are used to measure very low light intensities.12
In a photomultiplier tube, a photosensitive cathode emits electrons when struck by light. These electrons are then attracted to a series of dynodes, each held at a progressively higher positive voltage. When an electron hits a dynode, it causes the dynode to emit several secondary electrons. This multiplication effect cascades through each dynode, significantly amplifying the initial signal before it reaches the final detector. This principle is also applied in electron multipliers used in mass spectrometry to detect ion beams with extreme sensitivity.23
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mass spectrometryElectron multipliersElectrodes, called dynodes, are so arranged that each succeeding generation of electrons is attracted to the next dynode. For example, if 4 electrons are released at the first dynode, then 16 will emerge from the second and so forth. Gains of as much as one million areā¦
Read MoreElectrodes, called dynodes, are so arranged that each succeeding generation of electrons is attracted to the next dynode. For example, if 4 electrons are released at the first dynode, then 16 will emerge from the second and so forth. Gains of as much as one million areā¦
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radiation measurementConversion of light to chargeā¦a series of electrodes called dynodes that have the property of emitting more than one electron when struck by a single electron that has been accelerated from a previous dynode. After the multiplication process, the amplified pulse of electrons is collected at an anode that provides the tubeās output. Theā¦
Read Moreā¦a series of electrodes called dynodes that have the property of emitting more than one electron when struck by a single electron that has been accelerated from a previous dynode. After the multiplication process, the amplified pulse of electrons is collected at an anode that provides the tubeās output. Theā¦
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