Patent ID: 8716656

Claim:
An ion mobility spectrometer, comprising: a sample receiving device, a drift tube, a gas circuit system, wherein the drift tube is partitioned into an ionization region and a gas drift region by an ion gate, one end of the gas drift region opposite to the ionization region is provided with a detector for detecting ions, characterized in that the gas circuit system comprises: a drying gas circuit, a drift gas circuit, a doping gas circuit and a no-load gas circuit, wherein: the drying gas circuit provides dried and purified air to the drift gas circuit, the doping gas circuit and the no-load gas circuit respectively; the drift gas circuit introduces the dried and purified air as the drift gas flow into the gas drift region from the back end; the doping gas circuit provides an appropriate amount of dopant vapor and connects with the drying gas circuit based on external control instructions, selectively introducing the dopant vapor carried by the dried and purified air into the ionization region; and the no-load gas circuit introduces the dried and purified air into the ionization region.