16 - 21 June 2024
Yokohama, Japan
Conference 13093 > Paper 13093-22
Paper 13093-22

Development of broadband and narrowband coatings for future UV missions: increasing throughput, uniformity, and environmental stability in the far- and Lyman-ultraviolet

17 June 2024 • 10:20 - 10:40 Japan Standard Time | Room G414/415, North - 4F

Abstract

In pursuit of maturing high priority UV optics technology for the Habitable Worlds Observatory, we present laboratory reflectivity results and ongoing environmental stability testing of band-selecting filters designed for the Lyman-ultraviolet bandpass (LUV; 90-120 nm) and the far-ultraviolet bandpass (FUV; 120-150 nm), and reflectance uniformity of broadband (90 – 2500 nm) coatings. The band-selecting coatings are multilayer depositions of Al+LiF+SiC+LiF, and LaF3 +AlF3. These narrowband filters were developed in coordination with the Grupo de Óptica de Láminas Delgadas (GOLD) at the Instituto de Óptica-Consejo Superior de Investigaciones Cientificas for the Far- and Lyman-Ultraviolet Imaging Demonstrator (FLUID) sounding rocket payload. Environmental stability tests of Lyman alpha (Ly-α; 121.6 nm) suppressing filters that peak near 105 nm (“F110M”) and 140 nm (“F140M”) were conducted in the optical testing facilities at CU Boulder. Additionally, we present initial UV optics coating development results of MgF2 capped silicon wafers, and LiF capped aluminum, in collaboration with NASA’s Jet Propulsion Laboratory. These coatings were deposited using atomic layer deposition (ALD) at JPL, to advance the throughput efficiency of MgF2 protective capping layers for UV optics. Several MgF2 depositions varying in silicon wafer temperature and dielectric thickness have been fabricated to explore the deposition parameters thoroughly. Exploring deposition uniformity on scales larger than a witness coupon, we also present initial results on the reflectance uniformity of (≤ 6 inches) MgF2/Al ALD coated optics.

Presenter

Emily Farr
Univ. of Colorado Boulder (United States)
Emily is a graduate student at CU Boulder working on UV cubesats and rockets.
Application tracks: Astrophotonics
Presenter/Author
Emily Farr
Univ. of Colorado Boulder (United States)
Author
Kevin C. France
Univ. of Colorado Boulder (United States)
Author
Consejo Superior de Investigaciones Científicas (Spain), Instituto de Óptica "Daza de Valdés" (Spain)
Author
Carlos Honrado-Benítez
Consejo Superior de Investigaciones Científicas (Spain), Instituto de Óptica "Daza de Valdés" (Spain)
Author
Paloma López-Reyes
Consejo Superior de Investigaciones Científicas (Spain), Instituto de Óptica "Daza de Valdés" (Spain)
Author
NASA (United States), Jet Propulsion Lab. (United States)
Author
Robin E. Rodríguez
NASA (United States), Jet Propulsion Lab. (United States)
Author
Nicholas Kruczek
Univ. of Colorado Boulder (United States)
Author
Univ. of Colorado Boulder (United States)