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Next: 5.5 Vacuum Systems Up: 5.4 Ion Detection Previous: 5.4.1 Electron Multipliers   Contents

5.4.2 Other Ion Detection Techniques

Not all mass spectrometry experiments use an electron multiplier for ion detection. For example, a Faraday Cup is simply a single charged plate (and is therefore much less expensive and less prone to failure than an electron multiplier) that is useful for high current ion beams. The ion beam might be made to impinge on a phosphor screen (as is used in a television or a cathode ray tube display) with a photomultiplier used to detect the emitted photons. Finally, the detector/data system might be used in a pulse counting mode (rather than analog mode as mentioned in Section 5.4.1); this technique is used in low beam density experiments in which individual ions are counted.



John S. Riley, DSB Scientific Consulting