First Results from ZIMPOL II
We present an imaging polarimeter for the full Stokes vector (I,Q,U,V), based on fast polarization modulation and demodulation by a CCD sensor. In the second generation Zurich Imaging Polarimeter ZIMPOL II ferroelectric liquid crystals modulate the Stokes vector at a frequency of 1 kHz. A special CCD sensor is used as part of a synchronous demodulator. For the first time simultaneous high accuracy polarimetric measurements of the complete Stokes vector with a single CCD are possible. The Stokes vector images do not suffer from gain-table or flatfield effects. Seeing noise is avoided by the fast modulation frequency. The polarimetric efficiency is 0.71 for all polarized Stokes parameters. The useful wavelength range is 1000 Å with one modulator package. First results of this new instrument are presented and analysed to experimentally evaluate the performance of the system.
Key wordsinstrumentation: polarimeters array detectors ferroelectrics
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- Gandorfer, A.M.: 1998, Optical Engineering, submittedGoogle Scholar
- Keller, C.U., Aebersold, F., Egger, U., Povel, H.-P., Steiner, P. and Stenflo, J.O.: 1992, LEST Foundation Technical Report No. 53.Google Scholar
- Stenflo, J.O., Keller, C.U., and Povel, H.-P.: 1992, LEST Foundation Technical Report No. 54.Google Scholar