OSA's Digital Library

Journal of the Optical Society of America A

Journal of the Optical Society of America A

| OPTICS, IMAGE SCIENCE, AND VISION

  • Editor: Franco Gori
  • Vol. 28, Iss. 8 — Aug. 1, 2011
  • pp: 1668–1676

Limits on achievable intensity reduction with an optical occulter

Wasyl Wasylkiwskyj and Shahram Shiri  »View Author Affiliations


JOSA A, Vol. 28, Issue 8, pp. 1668-1676 (2011)
http://dx.doi.org/10.1364/JOSAA.28.001668


View Full Text Article

Enhanced HTML    Acrobat PDF (715 KB)





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

Share
Citations

Abstract

Deep shadowing of a normally incident plane wave by an opaque circular disk is partially negated by the formation of a region of strong intensity surrounding the axis passing normally through the disk center. This local intensity enhancement, historically referred to as the Poisson Spot (also known as the Spot of Arago), has been the principal source of difficulties in applications where a significant reduction of the incident intensity is essential. In particular, the NASA Terrestrial Planet Finder’s (TPF) mission requires suppression of direct starlight by at least 10 orders of magnitude over the entire visible spectral range. One technique that has been proposed for blocking the direct starlight is to use a rotationally symmetric disk with petallike segments along its boundary. We find that, even though such configurations could, indeed, theoretically provide the desired intensity reduction, they would require unreasonably small radii of curvature at the petals’ tips (in the range of micrometers). When the radii of curvature are increased to 3 mm , the intensity reduction drops to a modest 5 to 6 orders of magnitude. Given that for the NASA’s TPF mission the proposed occulter radius would be on the order of 25 m , even the 3 mm radius of curvature would be too small for any practical implementation. Further increases of the radius of curvature result in progressively poorer intensity suppression. As an alternative solution we propose an apodized circular disk. We show that with an optimized apodization function, intensity reductions of at least 10 orders of magnitude can be achieved over the entire visible spectral range. Numerical results are presented for parameters appropriate to the NASA TPF mission.

© 2011 Optical Society of America

OCIS Codes
(350.1260) Other areas of optics : Astronomical optics
(350.1270) Other areas of optics : Astronomy and astrophysics
(350.6090) Other areas of optics : Space optics

ToC Category:
Astronomical Optics

History
Original Manuscript: January 31, 2011
Revised Manuscript: May 2, 2011
Manuscript Accepted: May 4, 2011
Published: July 22, 2011

Citation
Wasyl Wasylkiwskyj and Shahram Shiri, "Limits on achievable intensity reduction with an optical occulter," J. Opt. Soc. Am. A 28, 1668-1676 (2011)
http://www.opticsinfobase.org/josaa/abstract.cfm?URI=josaa-28-8-1668

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited