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Polarimetric Calibration of Large-Aperture Telescopes I: The Beam-Expansion Method

H. Socas-Navarro
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Abstract

This paper describes a concept for the high-accuracy absolute calibration of the instrumental polarization introduced by the primary mirror of a large-aperture telescope. This procedure requires a small aperture with polarization calibration optics (e.g., mounted on the dome) followed by a lens that opens the beam to illuminate the entire surface of the mirror. The Jones matrix corresponding to this calibration setup (with a diverging incident beam) is related to that of the normal observing setup (with a collimated incident beam) by an approximate correction term. Numerical models of parabolic on-axis and off-axis mirrors with surface imperfections are used to explore its accuracy.

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H. Socas-Navarro. 2004-10-23. Polarimetric Calibration of Large-Aperture Telescopes I: The Beam-Expansion Method. https://doi.org/10.1364/josaa.22.000539

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