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Transpector XPR 3+ Operating Manual
"Method for linearization of ion currents in a quadrupole mass analyzer"
[US 5,889,281]
Abstract
A method of linearizing the sensitivity of a quadrupole mass spectrometric system
to allow the sensor to more accurately report partial pressures of a gas in high
pressure areas in which the reported data is effected by a number of loss
mechanisms. According to the invention, correction factors can be applied
empirically or software in a quadrupole mass analyzer system can be equipped
with correcting software to expand the useful range of the mass spectrometer.
"Ion collector assembly" [US 6,091,068]
Abstract
An ion collector includes a Faraday Cup collector having a conductive surface
disposed substantially parallel to and spaced from the axis of an entering particle
beam containing charged and uncharged particles. A grounded plate disposed in
the path of the particle beam allows incoming uncharged particles to impinge
thereupon. Preferably, the application of a suitable potential to the conductive plate
manipulates incoming charged ions to impinge upon either the electron multiplier
or the Faraday collector. The ion collector can further include an electron multiplier
used in conjunction with the Faraday collector to allow separate modes of
operations. Application of a suitable first potential to the electron multiplier can
cause charged particles to be deflected directly to the Faraday collector in one
mode, and application of a second potential can cause deflection of charged
particles to the electron multiplier, with the effects of the uncharged particles on the
output of the detector being minimized.
"Apparatus of measuring total pressure and partial pressure with common
electron beam" [US Patent Application 20020153820]
Abstract
An apparatus for determining both total and partial pressures of a gas using one
common electron beam includes a partial pressure ionization region and a total
pressure ionization region separated by a grid or aperture. A filament produces a
plurality of electrons which are focused into an electron beam by a repeller and an
aperture or an anode. The interactions between the electron beam and molecules
of said gas within the partial pressure and total pressure regions produces first and
second ion streams. A focus plate is biased such that the first ion stream is directed
to an analyzer which calculates the partial pressure of the gas. An ion collector
collects the ions from the second ion stream, where the resulting reference current
is used to determine the total pressure of the gas.