
15.1.
All-Reflecting Spectrometers
15.1.
ALL-REFLECTING SPECTROMETERS
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We first consider plane grating spectrometers with mirror optics to collimate
and focus the dispersed Hght. Instruments of this type, such as the Czemy-Tumer
and Ebert-Fastie designs, are used in laboratories and have been used as
astronomical spectrometers. The major disadvantage of the designs discussed
in this section is the lack of fi-eedom to choose the camera focal ratio
independently of the collimator focal ratio. In spite of this lack of flexibility,
the characteristics of these designs merit some discussion.
15.La. CZERNY-TURNER MOUNTING
The Czerny-Turner desig ...