ENERGY-LIMITED RESOLUTION WITH INTERFEROMETRIC DISPERSING ELEMENTS
Creators:Rupert, C. S.
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Publisher:Ohio State University
The spectral resolution attainable with a grating spectrometer under energy-limited conditions is examined. Other factors being equal, it is found to improve with increase in the theoretical diffraction-limited resolving power of the grating. This characteristic determines the manner in which a given grating should be mounted and used. The reflection echelon, which is essentially a coarse grating, offers one means of improving energy-limited resolution. Limitations which are inherent in a grating made up of laterallyspaced rulings are avoided in a stratified ``grating-in-depth'', formed by evenly spaced layers of low reflectivity. A similar advantage lies with the Fabry-Perot etalon. Ideally, the energy flux per unit spectral bandpass available with these devices is two orders of magnitude greater than that provided by a laterally ruled grating of the same area. Possibilities and limitations in realizing this gain are considered.
Author Institution: The Johns Hopkins University