Patent ID: 9683963
Date: 2017-06-20
CPC Classifications: G01N,H01J

Claim:
1. An ion mobility spectrometer comprising: an ion source, said source being filled with gas at gas pressure from generally at or between about 1 mBar to 1 Bar; an ion gate formed of a front cap electrode, followed by a front mesh and then by a back mesh, each individual mesh defining a plurality of mesh cells, each mesh cell having a mesh cell size between 0.1-1 mm, wherein the meshes are generally parallel with one another and spaced at a distance substantially equal to the mesh cell size; a radiofrequency (RF) generator connected between the meshes; a direct current (DC) generator configured to apply a switching or adjustable DC signal to the cap electrode and meshes; wherein the RF and DC generators are configured to form a local RF field between the front mesh and the back mesh while attracting ions toward the RF field region by a DC field which is sufficiently small to prevent ion penetration through the barrier of the RF field to thereby yield ion localization in local RF traps around mesh cells; an ion drift space filled with gas at pressure from generally at or between about (1 to 30) mBar; and an ion detector.