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Title: Polarization purity and cross-channel intensity correlations
We consider the question of monitoring polarization purity, that is, measuring deviations from orthogonalityδτandδϵof an ostensibly orthogonal polarization basis with a reference channel of ellipticityϵand tiltτ. A simple result was recently derived for a phase-sensitive receiver observing unpolarized radiation [IEEE Trans. Geosci. Remote Sens.62,2003610(2024)10.1109/TGRS.2024.3380531]: withρ(1)denoting the Pearson complex correlation coefficient between channelcomplex fields, it states that ∓cos⁡(2ϵ)δτ±iδϵ≈ρ(1)whenδτ,ϵ≪1. However, phase-sensitive (in-phase and quadrature) data are seldom available at optical frequencies. To that end, here we generalize the result by deriving a new equation for the polarization “alignment” error:cos2(2ϵ)δτ2+δϵ2≈ρ(2), whereρ(2)is the intensity cross-correlation coefficient. Only the measurement of the(real) intensitycross-correlation coefficient is needed when observing unpolarized light. For the special case of a linearly polarized basis, the tilt error is simplyδτ≈ρ(2), and for the circular basis case, with ellipticity deviationδϵfrom circular helicityπ/4 (the reference channel of opposite helicity),δϵ≈ρ(2). These results provide simple means to gauge the quality of polarimeters and depolarizers.  more » « less
Award ID(s):
2217182
PAR ID:
10631031
Author(s) / Creator(s):
;
Corporate Creator(s):
Editor(s):
anon
Publisher / Repository:
J. Optic. Soc.
Date Published:
Journal Name:
Journal of the Optical Society of America A
Volume:
42
Issue:
8
ISSN:
1084-7529
Page Range / eLocation ID:
1077
Subject(s) / Keyword(s):
polarimetry
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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