Advanced Environmentally Resistant Lithium Fluoride Mirror Coatings for the Next-Generation of Broadband Space Observatories

  title={Advanced Environmentally Resistant Lithium Fluoride Mirror Coatings for the Next-Generation of Broadband Space Observatories},
  author={Brian T. Fleming and Manuel A. Quijada and John J. Hennessy and Arika A. Egan and Javier Del Hoyo and Brian A. Hicks and James H. Wiley and Nicholas E. Kruczek and Nicholas Erickson and Kevin France},
  journal={arXiv: Instrumentation and Methods for Astrophysics},
  • B. Fleming, M. Quijada, +7 authors K. France
  • Published 20 December 2017
  • Materials Science, Physics
  • arXiv: Instrumentation and Methods for Astrophysics
Recent advances in the physical vapor deposition (PVD) of protective fluoride films have raised the far-ultraviolet (FUV: 912-1600 {\AA}) reflectivity of aluminum-based mirrors closer to the theoretical limit. The greatest gains, at more than 20%, have come for lithium fluoride-protected aluminum, which has the shortest wavelength cutoff of any conventional overcoat. Despite the success of the NASA FUSE mission, the use of lithium fluoride (LiF)-based optics is rare, as LiF is hygroscopic and… 
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