MULTIPOLE ASSEMBLY HAVING A MAIN MASS FILTER AND AN AUXILIARY MASS FILTER

摘要

OF THE DISCLOSURE 5 [0039] A multipole rod assembly for use in a mass spectrometer has a pluralityof rods aligned around and parallel to a common ion optical axis. Each rod consists oftwo rod pieces that are collinear with one another. Each rod piece has an opposing face that is perpendicular to the axis and faces the other rod. One rod piece has a recess is its face. The rod pieces are physically connected together with an insulating 10 piece located between the two rod pieces to electrically de-couple the rod pieces. Theinsulating piece has a shape and size that allows it to fit entirely within the recess so that, during operation of the mass spectrometer, the insulating piece is substantially screened from the ion optical axis.15Figure 2A