Operating Principle; Fig. 15: Principle Of The Quadrupole Mass Spectrometer System - Pfeiffer Vacuum PrismaPro QMG 250 Translation Of The Original

3.5 Operating principle
The PrismaPro compact mass spectrometer is a quadrupole mass spectrometer system for qualitative
and quantitative gas analysis within the high, and ultra-high vacuum range, for leak detection and to
identify any trace contaminations.
An electron beam ion source ionizes the neutral gas particles. A high-frequency electric quadrupole field
separates the generated ions from one another according to their mass to charge ratio. The detection of
the filtered ions is carried out using a Faraday Cup or secondary electron multiplier (EM). In doing so,
the ion flow detected is proportional to the partial pressure of the respective gas components. The
quadrupole mass spectrometer system is a relative measuring instrument which requires calibration
with respective calibration gases in order to achieve an accurate quantitative gas analysis. The quadru-
pole mass spectrometer system electronics generate and control the direct, high, and HF voltages re-
quired for the ion sources, mass filter, and detector.
The quadrupole mass spectrometer system enables configuration and operation via web-based Web UI
or by way of the quadrupole software PV MassSpec. PV MassSpec enables the evaluation, storage and
comparison of measured data.
A
3
Fig. 15:
A Ion formation in the ion source from electron impact ionization
B Ion separation according to the mass-to-charge ratio
C Ion detection in the ion detector
B
1
2
Principle of the quadrupole mass spectrometer system
1 Ion optic
2 Formation area
3 Filament
C
U + V · cos ω · t
Product description
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