Telescope polarization and image quality: Lyot coronagraph performance

J. B. Breckinridge, Russell A Chipman

Research output: Chapter in Book/Report/Conference proceedingConference contribution

7 Scopus citations

Abstract

In this paper we apply a vector representation of physical optics, sometimes called polarization aberration theory to study image formation in astronomical telescopes and instruments. We describe image formation in-terms of interferometry and use the Fresnel polarization equations to show how light, upon propagation through an optical system become partially polarized. We make the observation that orthogonally polarized light does not interfere to form an intensity image. We show how the two polarization aberrations (diattenuation and and retardance) distort the system PSF, decrease transmittance, and increase unwanted background above that predicted using the nonphysical scalar models. We apply the polarization aberration theory (PolAbT) described earlier (Breckinridge, Lam and Chipman, 2015, PASP 127, 445-468) to the fore-optics of the system designed for AFTA-WFIRST- CGI to obtain a performance estimate. Analysis of the open-literature design using PolAbT leads us to estimate that the WFIRST-CGI contrast will be in the 10-5 regime at the occulting mask. Much above the levels predicted by others (Krist, Nemati and Mennesson, 2016, JATIS 2, 011003). Remind the reader: 1. Polarizers are operators, not filters in the same sense as colored filters, 2. Adaptive optics does not correct polarization aberrations, 3. Calculations of both diattenuation and retardance are needed to model real-world telescope/coronagraph systems.

Original languageEnglish (US)
Title of host publicationSpace Telescopes and Instrumentation 2016: Optical, Infrared, and Millimeter Wave
PublisherSPIE
Volume9904
ISBN (Electronic)9781510601871
DOIs
StatePublished - 2016
EventSpace Telescopes and Instrumentation 2016: Optical, Infrared, and Millimeter Wave - Edinburgh, United Kingdom
Duration: Jun 26 2016Jul 1 2016

Other

OtherSpace Telescopes and Instrumentation 2016: Optical, Infrared, and Millimeter Wave
CountryUnited Kingdom
CityEdinburgh
Period6/26/167/1/16

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ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

Cite this

Breckinridge, J. B., & Chipman, R. A. (2016). Telescope polarization and image quality: Lyot coronagraph performance. In Space Telescopes and Instrumentation 2016: Optical, Infrared, and Millimeter Wave (Vol. 9904). [99041C] SPIE. https://doi.org/10.1117/12.2231242