Patent attributes
Mass spectrometry apparatus 105 comprises a serial arrangement of an ion source 110, first time of flight means, a field free region 120, means to fragment the molecules, a second time of flight means and a large area detector 160. The second time of flight means includes an ion mirror 150, the ion mirror 150 being arranged to produce a reflecting substantially quadratic field. The first time of flight means is arranged to provide spatial focusing concomitant with time focusing of ions at or near the entrance to the ion mirror 150. The means provided to fragment the ions front the first time of flight means can be a collision cell 140 or in the field free region 220 or in the first time of flight means. The means to fragment the molecules has a potential which is different from the potential at the entrance to the ion mirror 150, and the detecting surface of the detector 160 is mounted in the time focal surface of the ion mirror 150.
