Detectors are one of the key features of a UV-Vis detector and the right detector needs to be chosen for the analysis taking place.
Photoemissive tubeThe photoemissive tube is one which has a cathode plate surrounding a wire anode. When photons hit the cathode electrons are emitted producing a current.
PhotodiodeA plate which uses the semiconducting properties of silicon to measure the contact of electrons on the silicon surface. Not as sensitive as photomultipler tubes but very cheap.
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Photomultiplier tubeVery similar to a photoemissive tubes but multiple dynodes of increasing voltage lined up producing multiple photoelectrons. This is a way of increasing low signals by a large amount.
Charged coupled devicesThese are small devices that can record several signals simultaneously they are very useful and outpeform PMT but have limited flexibility of use due to band width issues.
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