Modelling of penetration of ions through a shutter grid in ion mobility spectrometers

Phenomena occurring in vicinity of the shutter grid are important for resolving power of ion mobility spectrometers and also for magnitude of the signal from these detectors. In this paper we present results of computer calculations concerning electric field and ion concentration distributions in neighbourhood of grid electrodes. Proposed model and methods of calculation give possibility for estimation of permeability of the grid and for determination of ion concentration profile behind the grid in dependence of grid dimensions and parameters of controlling voltage.