Instrument Description
EFOSC2 consists of the following elements:
- A slit wheel
- A filter wheel
- A grism wheel
- A collimator to make the beam parallel
- A halfwave plate or quarterwave plate for polarimetry
- Helium and Argon arc lamps for spectroscopic wavelength calibration
- Quartz lamp for internal flat fields
- A camera unit
- A calibration screen (not shown in the figure)
One of the features of this instruments is that all optical elements, other than apertures (masks, slits etc) are introduced into the optical path after the beam has been made parallel by passing it through a collimator.
Instrument Features
- CCD#40
- Imaging filters
- Grisms
- Order-sorting filters
- Star Plates (slits)
- Polarimetric elements
- Miscellaneous elements/Issues