Patent ID: 8193489
Filing Date: 2012-06-05
Classification: G21K,H01J

Abstract:
1. A multipole ion guide, comprising: rods disposed about an axis, each of the rods having a first end and a second end remote from the first end and a substantially constant diameter between the first end and a second end, wherein each of the rods is disposed at a respective greater distance from the axis at the first end than at the second end; means for applying a radio frequency (RF) voltage between adjacent pairs of rods, wherein the RF voltage creates a multipole field in a region between the rods; means for applying a direct current (DC) voltage drop along a length of each of the rods; and an input comprising a geometry configured to create radio frequency (RF) multipolar field of order hexapolar or greater; an output comprising a geometry configured to create two or more substantially quadrupolar RF field regions; and a transition region between the input and the output where the RF multipolar field of order hexapolar or greater transitions to the substantially quadrupolar RF fields.