In the embodiments shown in FIGS. 1, 2, 3A-3C, 4A-4D, the mass analyzer 30 comprises at least one ion trap 30 with an array of closely spaced apart electrodes (conductors). The electrodes comprise a center (ring) electrode 33 residing between two endcap electrodes 31, 32. The electrodes can have axially aligned apertures with a distance “b” between centers of adjacent apertures. The apertures can be arranged in a regular pattern or may be random. The ring electrode 33 can have one or more apertures 33a that will generally be larger than the first or second endcap electrode apertures. The term “ring electrode” refers to the center electrode in the ion trap array that is between the end cap or end electrodes 31, 32 and is not required to have a ring shape form factor, e.g., either in an outer perimeter or in a bounding channel of a respective ion trap. As is well known, a respective ion trap 30 can have short tubular channels of different diameters of aligned end cap and ring apertures. One or both of the endcap electrodes 31, 32 can comprise or be in the form of a mesh electrode and/or conductive screen.
