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

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. 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.