Resolving-power
Resolution (RR)
When closely
spaced line emission peaks can be resolved (such as the 577+579nm
Mercury doublet) and are clearly separated at Half the Max peak
height (HM), the distance between the peak and where its slope
intersects the HM is the resolving resolution in nanometer(s).
StellarNet estimates spectrometer resolution using RR. In a spectrograph
with a perfectly imaged detector array, RR will be the nm/pixel
dispersion. Larger slits decrease resolution as the image spreads
to adjacent detector pixels.
Line-width Resolution
(LR)
When a single
peak is measured at its Full Width Half Max (FWHM), the difference
where the slopes intersect the HM is the Line-width resolution
in nanometer(s). Conversion from LR to RR use: LR ~= 2 * RR.
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