Laboratory studies of alkali metal filter deposition, ultraviolet transmission, and visible blocking

Citation
Jt. Clarke et al., Laboratory studies of alkali metal filter deposition, ultraviolet transmission, and visible blocking, APPL OPTICS, 38(9), 1999, pp. 1803-1813
Citations number
12
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Optics & Acoustics
Journal title
APPLIED OPTICS
ISSN journal
00036935 → ACNP
Volume
38
Issue
9
Year of publication
1999
Pages
1803 - 1813
Database
ISI
SICI code
0003-6935(19990320)38:9<1803:LSOAMF>2.0.ZU;2-S
Abstract
Far-ultraviolet alkali metal or Wood's filters have been produced and teste d supporting the production of a flight filter for the Wide Field Planetary Camera 2 on the Hubble Space Telescope. Sodium layers 0.5-1-mu m thick tra nsmit up to 40% in the ultraviolet while efficiently blocking visible wavel engths. The prevention of visible pinholes is assisted by a clean, sleek-fr ee surface and a cooled substrate during deposition. The coatings are stabi lized efficiently by a bismuth overcoating whose transmission spectrum is p resented. We also report for the first time, to our knowledge, the first de monstrated long-wavelength cutoff from a lithium filter, with a shorter cut off wavelength than sodium and potentially higher stability for astronomica l imaging. (C) 1999 Optical Society of America.