Issue |
Astron. Astrophys. Suppl. Ser.
Volume 123, Number 3, June II 1997
|
|
---|---|---|
Page(s) | 589 - 592 | |
DOI | https://doi.org/10.1051/aas:1997175 | |
Published online | 15 June 1997 |
Wedged double Wollaston, a device for single shot polarimetric measurements
Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I–50125 Firenze, Italy
Received:
5
September
1996
Accepted:
21
October
1996
Simultaneous measurements of the polarized flux at angles 0, 45, 90 and 135
degrees can be performed by inserting a
simple combination of two Wollaston prisms and two wedges (cf. Fig. 1)
in the pupil plane of a camera/spectrometer multimode astronomical
instrument.
The first three elements of the Stokes vector can be therefore
determined from data taken at the same time and
without any need of rotating plates or other
moving elements which could be difficult to incorporate in
multimode astronomical instruments.
This paper describes the working principles of the wedged double Wollaston
and presents detailed parameters for prism combinations optimized for
imaging–polarimetry and spectro–polarimetry at "visual" (0.3 - 1.0 μm)
and near IR (1.0-2.5
μm) wavelengths.
The devices described here
could significantly simplify
the implementation of imaging and spectro–polarimetric modes
in astronomical multimode focal reducers.
Key words: instrumentation: miscellaneous, instrumentation: polarimeters
© European Southern Observatory (ESO), 1997