THORLABS RSB1 Operation Manual page 83

Raman Spectroscopy Bundle
· the calibration accuracy of the instrument's wavelength dispersion
· spectrum sampling as the spectrum counts are given by discrete pixels
A high spectral resolution is desirable for resolving Raman peaks that are spectrally close.
Spectral resolution is essentially determined by the element size of the coded aperture. The
corresponding values int he spec table are derived from Ne (calibration) and Xe (validation)
line lamp spectra. The inset in the
main panel in the left figure below
ter of the RSB1(/M)'s spectral range. The red arrow in the inset marks the selected spectral
line. The right figure below
describes the deviation of the peak's maximum position in wavelength space from the values
listed in the corresponding NIST tables for
wavelength derived from the measured spectrum, while the solid grey line indicates the NIST
wavelength for the selected Ne line. We specify spectral accuracy from peak positions; to un-
derline this, evaluation of centroid positions will also show that the spectral accuracy is within
the specified accuracy range. We define the spectral resolution as the full widths at half max-
imum (FWHM) of the spectral lines; the FWHM of the selected spectral line is marked in blue.
The figure below
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range. Circles indicate data from calibration (Ne) lines, squares show values from validation
(Xe) lines, and the colors represent six different units tested. The green and red horizontal lines
indicate 1σ and 3σ confidence intervals, respectively. As a result, we obtain a typical accuracy
of +/-0.05 nm, and derive a 3σ specification for spectral accuracy of +/- 0.15 nm. This trans-
lates to a spectral accuracy of 2.2 cm
Note that spectral accuracy does not depend on wavelength, but in going to cm
be higher in the lower energy range.
Rev: 1.0, 17-Sep-2021
left figure below
shows a magnified view of one spectral line from the cen-
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is a magnified view of the figure to the left. The spectral accuracy
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Characterization of the Spectral Accuracy and Spectral Resolution (FWHM)
shows the typical spectral accuracy of the RSB1(/M) over the full spectral
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at 500 cm
© 2021 Thorlabs
shows a typical Ne lamp spectrum. The
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Ne and Xe. The dashed green line is the peak
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, and 1.8 cm at 1800 cm
Chapter 8: Appendix
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.
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, accuracy will
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