Patent ID: 6653627
Filing Date: 2003-11-25
Classification: G01N,H01J

Abstract:
A method for selectively transmitting ions produced by a laser-based ionization technique, comprising the steps of:a) providing two electrodes including a first electrode and a second electrode defining a FAIMS analyzer therebetween; b) providing an asymmetric waveform and a direct-current compensation voltage, to at least one of the two electrodes to form an electric field therebetween, the field for effecting a difference in net displacement between ions in a time of one cycle of the applied asymmetric waveform for effecting a first separation of the ions by forming a subset thereof; c) producing ions within the electric field using a laser-based ionization technique; and, d) transporting said produced ions through the electric field in a direction approximately transverse to the electric field, wherein the ions are produced under other than high vacuum conditions.