VARIABLE DISPERSION MASS SPECTROMETER

摘要

The invention relates to a variable dispersion double-focusing mass spectrometer comprising at least a magnetic sector analyzer (4) preceding an electrostatic analyzer (6), which analyzers cooperate to form a direction and velocity focused image on a multichannel detector (34) locatable in the focal plane of the electrostatic analyzer (6). The geometrical parameters of the electrostatic analyzer are selected so that the magnification of the electrostatic analyzer is substantially zero, which makes it possible to use a variable radius electrostatic analyzer to vary the extent of the mass spectrum imaged on the detector (34) while still maintaining double focusing. A variable radius electrostatic analyzer suitable for use in the invention is also described.