Compact Wien filter/magnetic sector double‐focusing mass spectrometer

Abstract A compact Wien filter/magnetic deflector, double‐focusing mass spectrometer was constructed and tested. The Wien filter is sited inside the gap common with the magnetic deflector. The instrument first‐order ion‐optical parameters and the second‐order aberration coefficients are given. A brief description of the instrument is followed by the experimental results obtained on a methane sample. Jon currents of 1.6 × 10 −8 A were collected at a resolution of 170 for a main path radius of 56 mm.