The use of CCDs as focal plane detectors has changed the design concept for the polarimetric mode in the visible and, actually, also in the near infrared spectral ranges. Providing astronomical instrumentation with polarization sensitive crystal in appropriate configuration (Wollaston, Rochon, Glann-Thomson, and so on), together with half- or quarter- waveplate retarder, it is possible to determine the linear and/or circular Stokes parameters. The polarization analyser placed at the Asiago Faint Object Spectrographic Camera (AFOSC), allows simultaneous measurements of the two linear Stokes parameters usually named Q and U without any λ/2 retarder plate. Similar devices may be designed to be placed at every instrument with an accessible pupil. The paper reports details of the instrument concept and the results of observations of polarized and unpolarized standard stars, both in broad-band and spectro-polarimetry observing modes.
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