Speckle Image Reconstruction. Appendix 1.

Abstract

By adjusting the optical pathlengths of the MMT (Multiple Mirror Telescopes) telescopes, it is possible to make the MMT into a phased array with a 6.86 m baseline. A coherent, phased focus can be achieved with tilted focal planes if the tilt angle is chosen so that the internal phase differences exactly compensate the external phase differences. This amounts to a slight change in configuration such that the beams are brought together at f/8.39 rather than the originally designed f/9. We summarize experiments which have used the MMT subapertures as a phased array and as a coherent, phased telescope, and present a simple analysis of the tilted focal plane geometry for coherent observation. The phased operation of the MMT is important not only for obtaining high angular resolution, but also for obtaining the higher detection sensitivity which results from the better discrimination against the sky emission background for infrared diffraction limited images. Full-aperture (six-beams), diffraction-limited results for the unresolved source Gamma Orinois, the well-known close binary Capella and the resolved red supergiant Betelgeuse, (including a diffraction limited differential speckle image of the latter) are presented.

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1985
Accession Number
ADA158271

Entities

People

  • E. K. Hege
  • P. A. Strittmatter

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Arrays
  • Detection
  • Diffraction
  • Discrimination
  • Emission
  • Focal Planes
  • Geometry
  • Image Reconstruction
  • Mathematics
  • Observation
  • Phased Arrays
  • Plane Geometry
  • Sensitivity
  • Sizes (Dimensions)
  • Telescopes

Fields of Study

  • Physics

Readers

  • Astronomy/Astrophysics
  • Optical Physics and Photonics.

Technology Areas

  • Space
  • Space - Space Objects