Electrostatic Ion Shutter with Ejecting Electrode as a Part of a Ion Mobility Spectrometer

Abstract

In portable hand-held devices for trace explosive and narcotic detection the most perspective is use of a principle of ion mobility spectrometry owing to the best combination of cost, compactness, parameters of detection and a wide range of found out substances. Classical designs of a ion mobility spectrometer are represented by a set of the metal electrodes forming area with homogeneous longitudinal electric field, in a combination to an electric shutter and area of ionization to a source of ionization on the basis of a radioactive isotope. The extremely perspective problem is development of a compact not radioactive source of the ionization, allowing to generate ions both positive, and negative polarity and having low power consumption. The use pulse corona discharge as a source of ionization for a ion mobility spectrometer is represented to the most perspective. Application in a design of a pulse corona discharge ionization source allows, unlike systems with isotope 63Ni ionization, to do without application of an electrostatic ion shutter which separates ionization and drift chambers. However application of an ion shutter allows to achieve the best parameters of resolution and sensitivity. In the given work the scheme of operation and results of application of an electrostatic ion shutter as a part of a ion mobility spectrometer with a pulse corona discharge ionization source will be considered.