Oversimplified, compact double focusing mass spectrometer geometries

The simplest ways to construct double focusing mass spectrometer designs are those resulting from inserting plane condenser plates in the gap of two rectangular pole pieces or a cylindric condenser at the pole piece corner. The first order ion-optical parameters and aberration coefficients were calculated for double focusing Wien filter-magnetic deflector geometries over the useful range of the deflection angles. Similar calculations were performed for cylindric electric-magnetic crossed field sectors, for comparison. The illustrating numerical examples indicate the highest resolutions for the 90° deflecting Wien filter-magnet and crossed field geometries.