Metrohm NIRS XDS Process Analyzer – MicroBundle - Manual (Page 90)

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At the end of the test this dialog box is displayed. Click “OK” to
exit Instrument Calibration.
Information about the WST3Wxxx Transmission Wavelength Calibration Standard:
The transmission wavelength standard used
is traceable to NIST SRM-2035, through
direct comparison on the Metrohm Master
Transmission Instrument.
The optical materials used in the WST3Wxxx
Calibration Standard have very sharp bands,
which are found to be stable and
repeatable.
The Master Instrument was first calibrated using SRM-
2035, and the resulting peak positions of the
WST3Wxxx standard were determined. Each calibration
standard is verified for correct response prior to
shipment. The correlation of the calibration standard to
SRM-2035 is checked on a regular basis to assure
consistent response.
The XDS instrument is set to predetermined nominals
during Instrument Calibration, since these are the best-
known information for NIR peak wavelengths.
In Wavelength Certification, the NIST-stated uncertainty
of 1.0nm is applied.
10.4.4 Window Correction, Transmission Probes
Window Correction is a method to permit the user to calibrate the fiber optics using a calibration
fixture. Next, the fibers are inserted into the barrels, and the optical differences are mapped. This
gives a clear, repeatable measure of the optical difference between the two geometries.