Thermo Finnigan LCQ Deca XP Plus, Руководство по оборудованию

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Functional Description
__________________________________________________________________ Ion Optics
__________________ LCQ Deca XP Plus Hardware Manual _________________
1-17
1.2 Ion Optics
Ions enter the ion optics after passing through the skimmer. The ion optics
transmit ions from the API source to the mass analyzer. The ion optics consist
of one quadrupole, one octapole, and an interoctapole lens. See Figure 1-8.
The quadrupole is a quadrilateral array of square rods that acts as an ion
transmission device. An RF voltage (2.45 MHz, 400 V peak to peak) and dc
offset voltage (typically -10 to +10 V) that are applied to the rods give rise to
an electric field that guides the ions along the axis of the quadrupole. During
ion transmission, the offset voltage is negative for positive ions and positive
for negative ions.
The octapole is an octagonal array of cylindrical rods that acts as an ion
transmission device. An RF voltage (2.45 MHz, 400 V peak to peak) and dc
offset voltage (typically -10 to +10 V) that are applied to the rods give rise to
an electric field that guides the ions along the axis of the octapole. During ion
transmission, the offset voltage is negative for positive ions and positive for
negative ions. The quadrupole/octapole RF voltage is turned off during mass
analysis.
Figure 1-8. Ion optics
Ion Optics
Mass Analyzer
Electron Multiplier
Vacuum Manifold Cover Plate