next up previous contents
Next: Performance Up: Utrecht Echelle Spectrograph Previous: Overview

Design

The layout of the spectrograph is shown schematically in Figure gif. The slit S is at the focal plane of the telescope. The light from the slit image (beam a) is collimated (beam b) by an off-axis parabolic mirror C, and traverses the three cross-dispersing quartz prisms P1, P2 and P3 before beam c is incident on the echelle grating E. The axes of beams a, b and c are horizontal. The light is dispersed in the vertical plane (beam d) by the echelle grating (beam d) and is finally re-imaged by the camera.

  
TIFF ]

Figure: Schematic of the Utrecht Echelle Spectrograph (UES).

The main components are as follows:

  
Table: Spectral Format of the 31.6 grooves/mm Echelle Grating --- Sample Orders

  
Table: Spectral Format of the 79 grooves/mm Echelle Grating --- Sample Orders



next up previous contents
Next: Performance Up: Utrecht Echelle Spectrograph Previous: Overview




Tue Aug 15 16:42:46 BST 1995