Time of flight mass spectrometer employing a plurality of lenses focussing an ion beam in shift direction

摘要

A multi reflecting time-of-flight mass spectrometer MR TOF MS 11. the flight path of ions from an ion source 12 to a receiver is folded along a trajectory by two parallel gridless electrostatic mirrors 15, elongated in the shift direction 7, orthogonal to the direction of reflection. A set of multiple lenses 17 is positioned in the drift space 14 between the mirrors to provide for spatial focusing of ions in the plane of the folded ion path. Each mirror consists of at least 4 electrodes 15C, 15E, 15L arranged and controlled so that to improve ion optics properties. Namely, in addition to time-of-flight focusing in energy and spatial focusing across the plane of the folded ion path, the mirrors also provide time-of-flight focusing with respect to the spatial spread of ions across the said plane. Because of improved spatial and time focusing, the MR TOF MS of the invention provides for a wider acceptance and confinement of ion beam along an extended folded ion path.