The advancement of far-ultraviolet (FUV) coatings is essential to meet the specified throughput requirements of the Large UV/Optical/IR (LUVOIR) Surveyor Observatory which will cover wavelengths down to the 100 nm range. The biggest constraint in the optical thin film coating design is attenuation in the Lyman-Alpha Ultraviolet range of 100-130 nm in which conventionally deposited thin film materials used in this spectral region (e.g., aluminum [Al] protected with Magnesium fluoride [MgF₂]) often have high absorption and scatter properties degrading the throughput in an optical system. We investigate the use of optimally deposited aluminum and aluminum tri-fluoride (AlF₃) materials for reflecting and solar blind band-pass filter coatings for use in the FUV. Optical characterization of the deposited designs has been performed using UV spectrometry. The optical thin film design and optimal deposition conditions to produce superior reflectance and transmittance using Al and AlF₃ are presented.

Date Published: 5 September 2017
PDF: 7 pages
Proc. SPIE 10372, Material Technologies and Applications to Optics, Structures, Components, and Sub-Systems III, 1037204 (5 September 2017); doi: 10.1117/12.2274399

Published in SPIE Proceedings Vol. 10372:
Material Technologies and Applications to Optics, Structures, Components, and Sub-Systems III
Matthias Krödel; Joseph L. Robichaud; Bill A. Goodman, Editor(s)