Ion mobility spectrometer. The spectrometer includes an enclosure for receiving a sample therewithin and an electron beam window admits an electron beam into the enclosure to ionize the sample in an ionization region. A shutter grid is spaced apart from the ionization region and means are provided for...http://www.google.es/patents/US7105808?utm_source=gb-gplus-sharePatente US7105808 - Plasma ion mobility spectrometer
