Resolution of Wide-range Grating Spectrometers

Abstract

WHILE it is common experience that the wavenumber resolution of grating spectrometers tends to be constant over a wide wave-length range¹, the theoretical basis for this observation does not appear to have been clearly formulated. The reason for this omission is doubtless due to concentration of interest on a particular grating, or set of gratings, and to the diversity of sources of radiation and detectors used for different spectral regions. However, if an unlimited range of gratings be assumed, so that maximum diffracted energy can always be assured, and attention is confined to a black-body source, some simple relationships may readily be deduced.