A. Stavdas et al., THE DESIGN OF ABERRATION-CORRECTED CONCAVE HOLOGRAPHIC GRATINGS FOR THE LYMAN-FAR-ULTRAVIOLET SPECTROSCOPIC EXPLORER HIGH-RESOLUTION SPECTROGRAPH, J. mod. opt., 44(4), 1997, pp. 659-673
A design procedure for two aberration-corrected spherical concave grat
ings operating in the spectral range 91-103 nm (extreme-ultraviolet) i
s presented. The first configuration is a Rowland circle mount whereas
the second is based on the conditions of stationarity with respect to
wavelength for the second-order aberration coefficients, as well as t
he condition for stationary meridional coma. The first design has bett
er resolution whilst the latter design has a better overall degree of
aberration correction. Holographic gratings recorded with two divergin
g stigmatic sources are considered for both designs. The theoretical p
erformance of these gratings is very good across the spectral range of
interest. The combination of simplicity and comparatively low cost to
gether with very good aberration correction performance makes these gr
ating designs attractive for the Lyman Far-Ultraviolet Spectroscopic E
xplorer.