Agilent Technologies 4200 FlexScan, Руководство по эксплуатации

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Getting Started
Agilent 4200 FlexScan FTIR Operation Manual 21
Laser Frequency Calibration test
The Laser Frequency Calibration test measures the frequency (X-
axis) accuracy. The test is conducted by measuring a spectrum of a
polystyrene film. Absorbance frequencies from this spectrum are
compared to frequencies set by NIST SRM 1921 polystyrene film. The
software enables administrative-level users to use the test results to
set the laser calibration. Laser calibrations should only be set after
consultation with an Agilent technical support engineer. For this test,
a background is measured first. For 45 degree external reflectance
and grazing angle reflectance sample interfaces, the reflective
reference cap is required for background measurements. After the
background collection, a spectrum of polystyrene film is measured as
instructed by the software. When using the 45 degree external
reflectance and grazing angle reflectance interfaces, the polystyrene
sample should be placed between the reference cap and the sample
interface. For the ATR sample interface, the reference cap is not
required for a background, but the polystyrene test sample must be
pressed firmly against the diamond sample interface during the
sample collection. The specification is listed below for each sample
interface. The difference between any of the listed frequencies and
the standard value should be no greater than the specification.
Table 5. Minimum performance for the Laser Frequency Calibration test
Sample interface Specification
ATR <2 cm
-1
External reflectance <1 cm
-1
Grazing angle <1 cm
-1