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Title: An engineered design of a diffractive mask for high precision astrometry [Modeling a diffractive mask that calibrates optical distortions]

AutoCAD, Zemax Optic Studio 15, and Interactive Data Language (IDL) with the Proper Library are used to computationally model and test a diffractive mask (DiM) suitable for use in the Gemini Multi-Conjugate Adaptive Optics System (GeMS) on the Gemini South Telescope. Systematic errors in telescope imagery are produced when the light travels through the adaptive optics system of the telescope. DiM is a transparent, flat optic with a pattern of miniscule dots lithographically applied to it. It is added ahead of the adaptive optics system in the telescope in order to produce diffraction spots that will encode systematic errors in the optics after it. Once these errors are encoded, they can be corrected for. DiM will allow for more accurate measurements in astrometry and thus improve exoplanet detection. Furthermore, the mechanics and physical attributes of the DiM are modeled in AutoCAD. Zemax models the ray propagation of point sources of light through the telescope. IDL and Proper simulate the wavefront and image results of the telescope. Aberrations are added to the Zemax and IDL models to test how the diffraction spots from the DiM change in the final images. Based on the Zemax and IDL results, the diffraction spots aremore » able to encode the systematic aberrations.« less
 [1] ;  [2] ;  [3] ;  [3] ;  [3] ;  [4] ;  [5]
  1. Univ. of Connecticut, Storrs, CT (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  3. Gemini South Observatory (Chile)
  4. NASA Ames Research Center (ARC), Moffett Field, Mountain View, CA (United States)
  5. Univ. of Arizona, Tucson, AZ (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0277-786X
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Proceedings of SPIE - The International Society for Optical Engineering
Additional Journal Information:
Journal Volume: 9909; Journal ID: ISSN 0277-786X
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org:
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; adaptive optics; diffraction; exoplanets; light sources; mechanics; optics; telescopes; wavefronts; Zemax
OSTI Identifier: