US Patent 11373849 Mass spectrometer having fragmentation region

A mass spectrometer is disclosed comprising: a first vacuum chamber having an inlet aperture; a second vacuum chamber; a differential pumping aperture separating the vacuum chambers; and an ion guide arranged in the first vacuum chamber for guiding ions from the inlet aperture to and through the differential pumping aperture. The ion guide has a construction for handling high gas loads such that the spectrometer is able to maintain the gas pressure in the first vacuum chamber such that when ions are accelerated therethrough the ions collide with gas and fragment.