Littrow Spectroscope

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The Littrow Spectrograph

 

 

The Littrow design is very popular, only requiring a single achromat as a collimator/ imaging lens. More suited to higher f ratios (>f8) but can provide a reasonably compact assembly and high (R=10000) resolution. The Shelyak LHiresIII is a good example of this design.

(The Littrow design was developed into the original Spectra-L200 instrument, which unfortunately is currently unavailable. It used 150/ 300/ 600/ 1200 or 1800 l/mm gratings. Maximum resolution R=9000)

This article The Littrow Spectrograph gives details of the original L200 prototype build.

 HIRSS Fulvio Mete's high resolution version of the Littrow.