Patent ID: 6891153
Filing Date: 2005-05-10
Classification: H01J

Abstract:
1. A mass spectrometer comprising: an ion source for producing ions; an input vacuum chamber comprising at least one AC ion guide for transmitting said ions, said AC ion guide comprising a plurality of electrodes having apertures, said apertures being aligned so that ions travel through them as they are transmitted by said ion guide; an analyzer vacuum chamber comprising an ion mass analyzer disposed to receive ions after they have been transmitted by said ion guide; at least one differential pumping apertured electrode though which ions may pass, said at least one differential pumping apertured electrode being disposed between said input vacuum chamber and said analyzer vacuum chamber to permit said analyzer vacuum chamber to be maintained at a lower pressure than said input vacuum chamber; at least one alternating current (AC) generator connected to an input chamber reference potential for providing AC potentials to said plurality of electrodes; wherein: