Osservatorio Astrofisico di Arcetri

logosmallarcetri Arcetri Technical Reports 9/1994

A few Considerations on Resin Replicated Grisms

T. Oliva

Osservatorio Astrofisico di Arcetri


This report considers grisms with a mis--match between the refraction indices of the prism and of the grating. While the basic parameters of the grism (central wavelength, dispersion) are only influenced by the prism parameters (refraction index and aperture angle), the overall efficiency strongly depends on the grating parameters (refraction index and blaze angle).

Handy formulae for determining the correct combination of prism and grating parameters are given. A few considerations on the limiting resolving powers achievable with thin, strongly mis--matched grisms are also made.