Ion gate control method for ion mobility spectrometer

Abstract

The invention discloses an ion gate control method for an ion mobility spectrometer. The method comprises the step of controlling a complete working period of an ion gate to be subjected to a door opening stage, a shearing stage, a repulsion stage and a door closing stage through the voltage of a first grid electrode and the voltage of a second grid electrode. In the shearing stage, the rear edgeof an ion group is rapidly cut off, and axial stretching of the ion group in the shearing process is reduced; in the repulsion stage, the ion group is integrally pushed in a migration direction, and the axial compression of the ion group is realized by using the non-uniformity of a repulsion electric field. According to the method, on one hand, the ion group cutting and separating processes can beindependently controlled respectively, on the other hand, trailing of the rear edge caused by ion group cutting by the ion gate can be reduced, and the resolution capability of the ion mobility spectrometer can be improved.

Description

technical field [0001] The invention relates to the field of ion mobility spectrometry, in particular to an ion gate control method for ion mobility spectrometers. Background technique [0002] Ion mobility spectrometry (IMS) is a rapid detection technology for trace substances, which has the advantages of simple structure, high sensitivity, fast detection speed and working under normal pressure. The ion mobility spectrometer controls the charged particles to enter the drift region in a specific mode by switching the ion gate, and is detected by the detector after separation. [0003] The switching of the ion gate opening and closing state is usually realized by changing the voltage of the first grid electrode G1 and the second grid electrode G2: when the voltage difference between the first grid electrode G1 and the second grid electrode G2 is small, the ion The gate is opened, and ions can pass through; when the voltage difference between the first grid electrode G1 and t...

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Problems solved by technology

[0004] The traditional ion gate timing control method is to apply a pulse signal with a fixed width and amplitude on the ion gate grid. The main problem of this control method is that the cutting shape of the trailing edge of the ion cluster is not ideal.

[0005] The disclosure of the above background technical content is only used to assist in understanding the inventive concepts

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