Metrohm NIRS XDS RapidLiquid Analyzer - Manual (Page 39)

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Wavelength Linearization uses an internal wavelength standard set to determine a set of internal,
arbitrary peak positions that the instrument will use to maintain repeatability of wavelength response.
The NIR wavelength positions of
these peaks appear as shown.
The scale of this display is marked
in encoder pulses, which do not
relate to nanometers directly.
From the peaks, a linearization is
performed, which allows
assignment of nanometer values.
The “visible” portion of the
spectrum is similar. A linearization
is applied to this portion of the
spectrum.
Minor artifacts appear in these
raw spectra due to detector
crossover and other spectroscopic
reasons. After linearization these
artifacts are minimal or not
evident, some being beyond the
usable range of the instrument.
This test is run automatically as part of Instrument Calibration. The user must confirm the acceptance
of the linearizations. Click “OK” to accept for each wavelength region.
These peak positions are not meant to be
traceable, as the wavelength calibration of
the instrument is done on an external
standard, traceable to NIST.
The internal wavelength standards are used
to maintain the external wavelength
registration by use of software adjustment
for any external effects on the instrument.
Select Wavelength Linearization from the
Diagnostics menu. The instrument will scan
the reference.